Thursday, December 12, 2019

Yoga enhances many of the same brain structures and functions that benefit from aerobic exercise

Scientists have known for decades that aerobic exercise strengthens the brain and contributes to the growth of new neurons, but few studies have examined how yoga affects the brain. A review of the science finds evidence that yoga enhances many of the same brain structures and functions that benefit from aerobic exercise.
The review, published in the journal Brain Plasticity, focused on 11 studies of the relationship between yoga practice and brain health. Five of the studies engaged individuals with no background in yoga practice in one or more yoga sessions per week over a period of 10-24 weeks, comparing brain health at the beginning and end of the intervention. The other studies measured brain differences between individuals who regularly practice yoga and those who don't.
Each of the studies used brain-imaging techniques such as MRI, functional MRI or single-photon emission computerized tomography. All involved Hatha yoga, which includes body movements, meditation and breathing exercises.
"From these 11 studies, we identified some brain regions that consistently come up, and they are surprisingly not very different from what we see with exercise research," said University of Illinois kinesiology and community health professor Neha Gothe, who led the research with Wayne State University psychology professor Jessica Damoiseaux.
"For example, we see increases in the volume of the hippocampus with yoga practice," Gothe said. Many studies looking at the brain effects of aerobic exercise have shown a similar increase in hippocampus size over time, she said.
The hippocampus is involved in memory processing and is known to shrink with age, Gothe said. "It is also the structure that is first affected in dementia and Alzheimer's disease."
Though many of the studies are exploratory and not conclusive, the research points to other important brain changes associated with regular yoga practice, Damoiseaux said. The amygdala, a brain structure that contributes to emotional regulation, tends to be larger in yoga practitioners than in their peers who do not practice yoga. The prefrontal cortex, cingulate cortex and brain networks such as the default mode network also tend to be larger or more efficient in those who regularly practice yoga.
"The prefrontal cortex, a brain region just behind the forehead, is essential to planning, decision-making, multitasking, thinking about your options and picking the right option," Damoiseaux said. "The default mode network is a set of brain regions involved in thinking about the self, planning and memory."
Like the amygdala, the cingulate cortex is part of the limbic system, a circuit of structures that plays a key role in emotional regulation, learning and memory, she said.
The studies also find that the brain changes seen in individuals practicing yoga are associated with better performance on cognitive tests or measures of emotional regulation.
The discovery that yoga may have similar effects on the brain to aerobic exercise is intriguing and warrants more study, Gothe said.
"Yoga is not aerobic in nature, so there must be other mechanisms leading to these brain changes," she said. "So far, we don't have the evidence to identify what those mechanisms are."
She suspects that enhancing emotional regulation is a key to yoga's positive effects on the brain. Studies link stress in humans and animals to shrinkage of the hippocampus and poorer performance on tests of memory, for example, she said.
"In one of my previous studies, we were looking at how yoga changes the cortisol stress response," Gothe said. "We found that those who had done yoga for eight weeks had an attenuated cortisol response to stress that was associated with better performance on tests of decision-making, task-switching and attention."
Yoga helps people with or without anxiety disorders manage their stress, Gothe said.
"The practice of yoga helps improve emotional regulation to reduce stress, anxiety and depression," she said. "And that seems to improve brain functioning."
The researchers say there is a need for more - and more rigorous - research into yoga's effects on the brain. They recommend large intervention studies that engage participants in yoga for months, match yoga groups with active control groups, and measure changes in the brain and performance on cognitive tests using standard approaches that allow for easy comparisons with other types of exercise.
"The science is pointing to yoga being beneficial for healthy brain function, but we need more rigorous and well-controlled intervention studies to confirm these initial findings," Damoiseaux said.

Want to avoid the holiday blues? New report suggests skipping the sweet treats

If you're prone to depression, this holiday season you might want to say "bah humbug" to offers of sugar plum pudding, caramel corn and chocolate babka.
A new study from a team of clinical psychologists at the University of Kansas suggests eating added sugars - common in so many holiday foods - can trigger metabolic, inflammatory and neurobiological processes tied to depressive illness. The work is published in the journal Medical Hypotheses.
Coupled with dwindling light in wintertime and corresponding changes in sleep patterns, high sugar consumption could result in a "perfect storm" that adversely affects mental health, according to the researchers.
"For many people, reduced sunlight exposure during the winter will throw off circadian rhythms, disrupting healthy sleep and pushing five to 10% of the population into a full-blown episode of clinical depression," said Stephen Ilardi, KU associate professor of clinical psychology.
Ilardi, who coauthored the study with KU graduate students Daniel Reis (lead author), Michael Namekata, Erik Wing and Carina Fowler (now of Duke University), said these symptoms of "winter-onset depression" could prompt people to consume more sweets.
"One common characteristic of winter-onset depression is craving sugar," he said. "So, we've got up to 30% of the population suffering from at least some symptoms of winter-onset depression, causing them to crave carbs - and now they're constantly confronted with holiday sweets."
Ilardi said avoidance of added dietary sugar might be especially challenging because sugar offers an initial mood boost, leading some with depressive illness to seek its temporary emotional lift.
"When we consume sweets, they act like a drug," said the KU researcher, who also is author of "The Depression Cure" (First De Capo Press, 2009). "They have an immediate mood-elevating effect, but in high doses they can also have a paradoxical, pernicious longer-term consequence of making mood worse, reducing well-being, elevating inflammation and causing weight gain."
The investigators reached their conclusions by analyzing a wide range of research on the physiological and psychological effects of consuming added sugar, including the Women's Health Initiative Observational Study, the NIH-AARP Diet and Health Study, a study of Spanish university graduates, and studies of Australian and Chinese soda-drinkers.
Ilardi cautioned it might be appropriate to view added sugar, at high enough levels, as physically and psychologically harmful, akin to drinking a little too much liquor.
"We have pretty good evidence that one alcoholic drink a day is safe, and it might have beneficial effect for some people," he said. "Alcohol is basically pure calories, pure energy, non-nutritive and super toxic at high doses. Sugars are very similar. We're learning when it comes to depression, people who optimize their diet should provide all the nutrients the brain needs and mostly avoid these potential toxins."
The researchers found inflammation is the most important physiological effect of dietary sugar related to mental health and depressive disorder.
"A large subset of people with depression have high levels of systemic inflammation," said Ilardi. "When we think about inflammatory disease we think about things like diabetes and rheumatoid arthritis - diseases with a high level of systemic inflammation. We don't normally think about depression being in that category, but it turns out that it really is - not for everyone who's depressed, but for about half. We also know that inflammatory hormones can directly push the brain into a state of severe depression. So, an inflamed brain is typically a depressed brain. And added sugars have a pro-inflammatory effect on the body and brain."
Ilardi and his collaborators also identify sugar's impact on the microbiome as a potential contributor to depression.
"Our bodies host over 10 trillion microbes and many of them know how to hack into the brain," Ilardi said. "The symbiotic microbial species, the beneficial microbes, basically hack the brain to enhance our well-being. They want us to thrive so they can thrive. But there are also some opportunistic species that can be thought of as more purely parasitic - they don't have our best interest in mind at all. Many of those parasitic microbes thrive on added sugars, and they can produce chemicals that push the brain in a state of anxiety and stress and depression. They're also highly inflammatory."
Ilardi recommended a minimally processed diet rich in plant-based foods and Omega-3 fatty acids for optimal psychological benefit. As for sugar, the KU researcher recommended caution - not just during the holidays, but year-round.
"There's no one-size-fits-all approach to predicting exactly how any person's body will react to any given food at any given dose," Ilardi stated. "As a conservative guideline, based on our current state of knowledge, there could be some risk associated with high-dose sugar intake - probably anything above the American Heart Association guideline, which is 25 grams of added sugars per day."

The relationship between migraine and exercise

A recent study published in the journal Cephalalgia, the official journal of the International Headache Society, highlights an overlooked relationship between migraine and exercise. The study, entitled "Anxiety sensitivity and intentional avoidance of physical activity in women with probable migraine", was led by Samantha G Farris, from Rutgers, Department of Psychology, the State University of New Jersey, NJ, USA.
Migraine affects around 10-15% of the population around the globe, and among its most common diagnosis criteria include a throbbing, unilateral head pain, hypersensitivity to lights, sounds, odors, and aggravation by activity. Although regular aerobic exercise has been strongly recommended by clinicians as an adjuvant option for migraine prevention, for up to 1/3 of patients, physical exercise can be a trigger of migraine attacks, thus, it can instead be avoided as a strategy to manage migraine. As observed with other pain conditions, anxiety sensitivity, which refers to one's fear of experiencing anxiety arousal due to harmful physical, cognitive and socially-observable consequences, may be related to PA avoidance in migraine patients. This seems to be the true especially with vigorous PA, as this exercise intensity is perceived as potentially triggering or worsening of migraine attacks.
In this study, the researchers assessed 100 women with probable migraine, who filled an online survey covering anxiety sensitivity scores, intentional avoidance of moderate and vigorous physical activity (PA) in the past month, which was based on the Global Physical Activity Questionnaire (GPAQ), as well as the self-rated perception (0-100%) that PA would trigger a migraine attack and worse migraine symptoms.
The results showed that increased anxiety sensitivity scores associated with PA avoidance of both moderate and vigorous intensities. One-point increase in the anxiety sensitivity scale resulted in up to 5% increase in the odds for avoiding PA. Concerns about the physical consequences of bodily sensations (e.g. difficulty breathing) associated with a 7.5-fold higher odds for avoiding vigorous PA, while cognitive consequences of bodily sensations (e.g. inability to concentrate), which is thought to reflect headache-related disability, associated with a 5.2-fold higher odds for avoiding moderate PA. Anxiety sensitivity scores positively associated with stronger expectations of vigorous-intensity PA as a triggering and worsening factor for migraine.
This study revealed a relevant but overlooked aspect of migraine. Migraine is a highly prevalent and disabling neurological disorder, in which regular PA is part of current non-pharmacological treatment recommendations. As pointed out by the authors "Patients with migraine and elevated anxiety sensitivity could benefit from tailored, multi-component intervention, ideally including: Psychoeducation about the positive effect of PA on migraine and the detrimental effect of avoidance, feedback about the perceived versus actual rates of PA in triggering/worsening migraine, and use of gradual exposure to facilitate desensitization to avoided of PA and related bodily sensations."

Hydration may affect cognitive function in some older adults

Not getting enough water is enough to make you feel sluggish and give you a headache, but a new Penn State study suggests it may also relate to cognitive performance.
The researchers investigated whether hydration levels and water intake among older adults was related with their scores on several tests designed to measure cognitive function. They found that among women, lower hydration levels were associated with lower scores on a task designed to measure motor speed, sustained attention, and working memory. They did not find the same result for men.
The findings were recently published in the European Journal of Nutrition.
"The study gives us clues about how hydration and related drinking habits relate to cognition in older adults," said Hilary Bethancourt, a postdoctoral scholar in biobehavioral health and first author on the study. "This is important because older adults already face increased risk of cognitive decline with advancing age and are often less likely than younger adults to meet daily recommendations on water intake."
Asher Rosinger, Ann Atherton Hertzler Early Career Professor in Global Health, said the researchers found similar results when the participants were overhydrated.
"We found a trend suggesting overhydration may be just as detrimental to cognitive performance as dehydration for older adults," said Rosinger, who also directs the Water, Health, and Nutrition Laboratory and was senior author on the study. "Because of this, being in the 'sweet spot' of hydration seems to be best for cognitive function, especially for tasks requiring sustained attention."
According to the researchers, scientists have long suspected that dehydration may have an effect on cognitive performance. However, previous studies have largely focused on young, healthy people who are dehydrated after exercise and/or being in the heat.
Bethancourt said that because exercise and elevated ambient and body temperatures can have their own, independent effects on cognition, she and the other researchers were interested in the effects of day-to-day hydration status in the absence of exercise or heat stress, especially among older adults.
"As we age, our water reserves decline due to reductions in muscle mass, our kidneys become less effective at retaining water, and hormonal signals that trigger thirst and motivate water intake become blunted," Bethancourt said. "Therefore, we felt like it was particularly important to look at cognitive performance in relation to hydration status and water intake among older adults, who may be underhydrated on a regular basis."
For the study, the researchers used data from a nationally representative sample of 1271 women and 1235 men who were 60 years of age or older. Data were collected by the Nutrition and Health Examination Survey. Participants gave blood samples and were asked about all foods and drinks consumed the previous day. The researchers calculated hydration status based on concentrations of sodium, potassium, glucose, and urea nitrogen in participants' blood. Total water intake was measured as the combined liquid and moisture from all beverages and foods.
Participants also completed three tasks designed to measure different aspects of cognition, with the first two measuring verbal recall and verbal fluency, respectively.
A final task measured processing speed, sustained attention, and working memory. Participants were given a list of symbols, each matched with a number between one and nine. They were then given a list of numbers one through nine in random order and asked to draw the corresponding symbol for as many numbers as possible within two minutes.
Bethancourt said that when they first plotted the average test scores across different levels of hydration status and water intake, there appeared to be a distinct trend toward higher test scores in relation to adequate hydration and/or meeting recommended water intake. However, much of that was explained by other factors.
"Once we accounted for age, education, hours of sleep, physical activity level, and diabetes status and analyzed the data separately for men and women, the associations with hydration status and water intake were diminished," Bethancourt said. "A trend toward lower scores on the number-symbol test among women who were categorized as either underhydrated or overhydrated was the most prominent finding that remained after we accounted for other influential factors."
Bethancourt said that because the data was cross-sectional, they can't be sure whether suboptimal hydration levels are causing cognitive impairment or if people with impaired cognition are just more likely to be under- or overhydrated. The researchers were also unsure why they failed to see the same associations among men. Still, she said the results raise interesting questions.
"It was interesting that even though the test of attention, processing speed, and working memory took only a few minutes, it was the one most strongly associated with lower hydration levels," Bethancourt said. "Other research has similarly suggested that attention may be one of the cognitive domains most affected by hydration status. This left us wondering what the effects of inadequate hydration might be on more difficult tasks requiring longer periods of concentration and focus."
Rosinger said the findings suggest older adults may want to pay close attention to their hydration status, by both consuming enough liquids to avoid dehydration as well as ensuring adequate electrolyte balance to avoid overhydration.
"Because older adults may not necessarily feel thirsty when their body is reaching a state of underhydration and may be taking diuretics that can increase salt excretion, it is important for older adults and their physicians to better understand the symptoms of being both under- and overhydrated," said Rosinger.
W. Larry Kenney, Marie Underhill Noll Chair in Human Performance, and David M. Almeida, professor of human development and family studies, also participated in this work.

Wednesday, December 11, 2019

Take long naps? Sleep more than nine hours a night? Your stroke risk may be higher

People who take long naps during the day or sleep nine or more hours at night may have an increased risk of stroke, according to a study published in the December 11, 2019, online issue of Neurology®, the medical journal of the American Academy of Neurology. People who took a regular midday nap lasting more than 90 minutes were 25 percent more likely to later have a stroke than people who took a regular nap lasting from one to 30 minutes. People who took no naps or took naps lasting from 31 minutes to one hour were no more likely to have a stroke than people who took naps lasting from one to 30 minutes.
"More research is needed to understand how taking long naps and sleeping longer hours at night may be tied to an increased risk of stroke, but previous studies have shown that long nappers and sleepers have unfavorable changes in their cholesterol levels and increased waist circumferences, both of which are risk factors for stroke," said study author Xiaomin Zhang, MD, PhD, of Huazhong University of Science and Technology in Wuhan, China. "In addition, long napping and sleeping may suggest an overall inactive lifestyle, which is also related to increased risk of stroke."
The study involved 31,750 people in China with an average age of 62. The people did not have any history of stroke or other major health problems at the start of the study. They were followed for an average of six years. During that time, there were 1,557 stroke cases.
The people were asked questions about their sleep and napping habits. Midday napping is common in China, Zhang said. Eight percent of the people took naps lasting more than 90 minutes. And 24 percent said they slept nine or more hours per night.
The study found that people who sleep nine or more hours per night are 23 percent more likely to later have a stroke than people who sleep seven to less than eight hours per night. People who sleep less than seven hours per night or between eight and less than nine hours per night were no more likely to have a stroke than those who slept from seven to less than eight hours per night.
The results were all adjusted for other factors that could affect the risk of stroke. These include high blood pressure, diabetes and smoking.
People who were both long nappers and long sleepers were 85 percent more likely to later have a stroke than people who were moderate sleepers and nappers.
The researchers also asked people about how well they slept. People who said their sleep quality was poor were 29 percent more likely to later have a stroke than people who said their sleep quality was good.
Of the long nappers, 1 percent of cases per person-years later had a stroke, compared to 0.7 percent of cases per person-years of the moderate nappers. The numbers were the same for the long and moderate sleepers, with 1 percent of cases per person-years compared to 0.7 percent of cases per person-years having a stroke.
"These results highlight the importance of moderate napping and sleeping duration and maintaining good sleep quality, especially in middle-age and older adults," Zhang said.
Zhang noted that the study does not prove cause and effect between long napping and sleeping and stroke. It only shows an association.
Limitations of the study include that information on sleep and napping was taken from questionnaires, not from recording people's actual sleep and information was not collected on sleep disorders such as snoring and sleep apnea. Also, the study involved older, healthy Chinese adults, so the results may not apply to other groups.

Skipping one night of sleep may leave insomniacs twice as impaired

A new study conducted by researchers at Washington State University shows that individuals with chronic sleep-onset insomnia who pulled an all-nighter performed up to twice as bad on a reaction time task as healthy normal sleepers. Their findings were published today in the online journal Nature and Science of Sleep. Poor daytime functioning is a frequent complaint among those suffering from insomnia, said lead author Devon Hansen, an assistant professor in the Elson S. Floyd College of Medicine and a researcher in the WSU Sleep and Performance Research Center. However, previous studies have found that their daytime cognitive performance is not significantly degraded, seemingly suggesting that it is a perceived issue that does not reflect a real impairment. The WSU study of individuals with sleep-onset insomnia revealed that the impairment may in fact be real but hidden during the normal day--yet exposed after pulling an all-nighter, which impacted them much more than age-matched control subjects.
The finding caught the WSU research team by surprise.
"There has been a theory about what perpetuates insomnia that focuses on hyperarousal, an activation in their system that keeps those with insomnia from being able to wind down when they go to bed," Hansen said. "We thought that this hyperarousal would protect them to some extent and had hypothesized that their performance after a night of total sleep deprivation would be better than normal healthy sleepers. Instead, we found the exact opposite."
Hansen, who in a previous career worked as a therapist in a sleep clinic, said the study adds credibility to insomnia patients' experiences. She also said it serves as a warning to poor sleepers that they should try to maintain a regular sleep schedule and avoid pushing their limits by staying up all night.
The research team studied 14 volunteer participants. Half of the group consisted of individuals who had chronic sleep-onset insomnia, the inability to fall asleep within 30 minutes for at least three nights a week for more than three months. The other half were healthy normal sleepers who served as controls. The two groups of participants were matched in age, with all participants aged between 22 and 40 and an average age of 29 for both groups.
Participants spent a total of five days and four nights in the sleep laboratory. They were allowed to sleep normally during the first two nights. They were kept awake the next night and following day--totaling 38 hours of total sleep deprivation--followed by a night of recovery sleep.
During their time awake, participants completed a series of performance tasks every three hours. This included a widely used alertness test known as the psychomotor vigilance test (PVT), which measures participants' response times to visual stimuli that appear on a screen at random intervals. The researchers analyzed PVT data for lapses of attention (i.e., slow reaction times) and false starts (i.e., responses that occur before the stimulus appears), comparing the findings between the two groups both before and during sleep deprivation.
Before sleep deprivation, the insomnia group's performance on the PVT looked very similar to that of the control group. However, as soon as sleep deprivation started the researchers began to see a dramatic increase in lapses of attention and false starts in the insomnia group. At one point during the night, their performance was twice as bad as that of the healthy normal sleepers.
"Our study suggests that even with a few hours of sleep deprivation--which people routinely experience for work or family reasons--those with sleep-onset insomnia may be much more impaired than those who normally sleep well at night," Hansen said. "This may increase their risk of errors and accidents whenever time-sensitive performance is required, such as while driving or when focused on a safety-critical task."
Hansen cautioned that since their study looked specifically at individuals with sleep-onset insomnia, their findings may not hold up in other insomnia subtypes, such as sleep-maintenance insomnia--which is characterized by difficulty staying asleep--and terminal insomnia--which involves early-morning awakenings. She plans to repeat the study in those groups to find out.

Diet, not exercise, may be key to addressing our biggest cause of liver disease

Edith Cowan University researchers have found that a chronic disease affecting up to 80 per cent of overweight people may be causing an iron deficiency that simply leaves them too tired to get off the couch.
Fatty liver disease affects about one in three Australians and is often associated with being overweight or obese. If left untreated, it can lead to liver cirrhosis, liver cancer and increase the risk of a heart attack.
But the remedy - to lose weight through diet or exercise - is often difficult to achieve for affected individuals.
In other words, it may not be laziness but lack of iron which is important for energy production that is stopping people with non-alcoholic liver disease from addressing their condition. -
This research indicates that people with the condition may be physiologically incapable of exercise due to iron not being available for the body to use normally, which is very similar to the effects observed in people who have a true iron deficiency.
The new research, under the direction of lead researcher Professor John Olynyk, will help guide future treatment for people with non-alcoholic fatty liver disease.
The body is like a car
ECU researchers measured the cardiovascular fitness of 848 17-year-old West Australians enrolled in the well known Raine Study and found that those with non-alcoholic fatty liver disease had lower physical work capacity independent of their weight.,
This reduced physical work capacity was also strongly related to parameters suggesting that iron is not being made available to the body for normal metabolism.
Professor John Olynyk said the study showed that people with non-alcoholic-fatty-liver disease had lower cardiovascular fitness, which was likely caused by a functional iron deficiency.
"We know that an iron deficiency can cause lethargy and fatigue, making it harder for people to exercise," he said.
"What is likely happening is that non-alcoholic fatty liver disease is impeding the body's ability to provide adequate iron into the blood to fuel processes such as energy and blood cell production.
"To use an analogy, if you imagine the body as a car and iron as its fuel, what is likely happening is that there is plenty of iron, or fuel in the tank, but the non-alcoholic fatty liver disease has caused the fuel line to shrink, so there's not enough fuel can get to the engine."
Diet before exercise
Professor Olynyk said the findings were useful for guiding the treatment of non-alcoholic fatty liver disease.
"The main treatment is lifestyle change aimed at reducing weight, primarily achieved through exercise and a modified diet," he said.
"In particular, there is evidence published by other investigators in the field that the Mediterranean diet can reduce the severity of non-alcoholic fatty liver disease. This is because it is high in foods like fruit and vegetables and whole grains, which have anti-inflammatory properties.
"This research shows that it may be more effective to first focus on new ways to improve the availability of iron to the body, enabling diet and physical activity to have better and more sustained effects on weight and the severity of their non-alcoholic fatty liver disease."

Study finds association between poor diet, age-related macular degeneration

Participants who ate a diet high in red and processed meat, fried food, refined grains and high-fat dairy were three times more likely to develop an eye condition that damages the retina and affects a person's central vision, according to the results of a study from the University at Buffalo.
The condition is called late-stage age-related macular degeneration (AMD). AMD is an irreversible condition that affects a person's central vision, taking away their ability to drive, among other common daily activities.
"Treatment for late, neovascular AMD is invasive and expensive, and there is no treatment for geographic atrophy, the other form of late AMD that also causes vision loss. It is in our best interest to catch this condition early and prevent development of late AMD," said Shruti Dighe, who conducted the research as part of her master's in epidemiology at UB's School of Public Health and Health Professions.
And that's why the finding that diet plays a role in AMD is so intriguing, added Dighe, who is now pursuing her PhD in cancer sciences at Roswell Park Comprehensive Cancer Center.
It turns out that a Western dietary pattern, one defined as high in consumption of red and processed meat, fried food, refined grains and high-fat dairy, may be a risk factor for developing late AMD.
However, a Western diet was not associated with development of early AMD in the study, published this month in the British Journal of Ophthalmology.
The authors studied the occurrence of early and late AMD over approximately 18 years of follow-up among participants of the Atherosclerosis Risk in Communities (ARIC) Study.
Dighe and colleagues used data on 66 different foods that participants self-reported consuming between 1987 and 1995 and identified two diet patterns in this cohort -- Western and what researchers commonly refer to as "prudent" (healthy) -- that best explained the greatest variation between diets.
"What we observed in this study was that people who had no AMD or early AMD at the start of our study and reported frequently consuming unhealthy foods were more likely to develop vison-threatening, late stage disease approximately 18 years later," said study senior author Amy Millen, PhD, associate professor and associate chair of epidemiology and environmental health at UB.
This U.S.-based study is one of the first examining diet patterns and development of AMD over time. The other studies were conducted in European cohorts.
Early AMD is asymptomatic, meaning that people often don't know that they have it. To catch it, a physician would have to review a photo of the person's retina, looking for pigmentary changes and development of drusen, or yellow deposits made up of lipids. With early AMD, there could be either atrophy or a buildup of new blood vessels in the part of the eye known as the macula.
"When people start developing these changes they will begin to notice visual symptoms. Their vision will start diminishing," Dighe said. "This is advanced or late stage AMD."
But not everyone who has early AMD progresses to the more debilitating late stage.
To date, most research has been conducted on specific nutrients -- such as high-dose antioxidants -- that seem to have a protective effect. But, Dighe explains, people consume a variety of foods and nutrients, not just one or two, and that's why looking at diet patterns helps tell more of the story.
"Our work provides additional evidence that that diet matters," Millen added. "From a public health standpoint, we can tell people that if you have early AMD, it is likely in your best interest to limit your intake of processed meat, fried food, refined grains and high-fat dairy to preserve your vision over time."

Refined carbs may trigger insomnia

An estimated 30% of adults experience insomnia, and a new study by researchers at Columbia University Vagelos College of Physicians and Surgeons suggests that diet may be partly to blame.
The study found that postmenopausal women who consumed a diet high in refined carbohydrates--particularly added sugars--were more likely to develop insomnia.
Women whose diet included higher amounts of vegetables, fiber, and whole fruit (not juice) were less likely to develop problems with insomnia.
"Insomnia is often treated with cognitive behavioral therapy or medications, but these can be expensive or carry side effects," says the study's senior author James Gangwisch, PhD, assistant professor at Columbia University Vagelos College of Physicians and Surgeons.
"By identifying other factors that lead to insomnia, we may find straightforward and low-cost interventions with fewer potential side effects."
The findings were published Dec. 11 online in The American Journal of Clinical Nutrition.
Link Between Diet and Sleep Is an Emerging Research Area
Previous studies have explored a possible link between refined carbohydrates and insomnia, but results have been inconsistent. And because the studies didn't follow individuals over time, it's not clear if a diet that's high in refined carbs triggered the onset of insomnia, or if insomnia caused individuals to eat more sweets.
One way to determine if carb intake is causing sleep problems is to look for the emergence of insomnia in people with different diets.
In the current study, Gangwisch and his team gathered data from more than 50,000 participants in the Women's Health Initiative who had completed food diaries. The researchers looked at whether women with higher dietary glycemic index were more likely to develop insomnia.
All Carbs Aren't Created Equally
Different kinds and amounts of carbohydrates increase blood sugar levels to varying degrees. Highly refined carbohydrates--such as added sugars, white bread, white rice, and soda--have a higher glycemic index, and cause a more rapid increase in blood sugar.
"When blood sugar is raised quickly, your body reacts by releasing insulin, and the resulting drop in blood sugar can lead to the release of hormones such as adrenaline and cortisol, which can interfere with sleep," Gangwisch says.
The researchers hypothesized that the rapid spikes and troughs in blood sugar after eating refined carbs may trigger insomnia.
Refined Carbs Triggered Insomnia
They found that the higher the dietary glycemic index--particularly when fueled by the consumption of added sugars and processed grains--the greater the risk of developing insomnia. They also discovered that women who consumed more vegetables and whole fruits (not juices) were less likely to develop insomnia.
"Whole fruits contain sugar, but the fiber in them slow the rate of absorption to help prevent spikes in blood sugar," says Gangwisch. "This suggests that the dietary culprit triggering the women's insomnia was the highly processed foods that contain larger amounts of refined sugars that aren't found naturally in food."
Since most people, not just postmenopausal women, experience a rapid rise in blood sugar after eating refined carbohydrates, the authors suspect that these findings may also hold true in a broader population.
"Based on our findings, we would need randomized clinical trials to determine if a dietary intervention, focused on increasing the consumption of whole foods and complex carbohydrates, could be used to prevent and treat insomnia," says Gangwisch.

Play sports for a healthier brain Even football, soccer, hockey athletes have healthier brains

There have been many headlines in recent years about the potentially negative impacts contact sports can have on athletes' brains. But a new Northwestern University study shows that, in the absence of injury, athletes across a variety of sports -- including football, soccer and hockey -- have healthier brains than non-athletes.
"No one would argue against the fact that sports lead to better physically fitness, but we don't always think of brain fitness and sports," said senior author Nina Kraus, the Hugh Knowles Professor of Communication Sciences and Neurobiology and director of Northwestern's Auditory Neuroscience Laboratory (Brainvolts). "We're saying that playing sports can tune the brain to better understand one's sensory environment."
Athletes have an enhanced ability to tamp down background electrical noise in their brain to better process external sounds, such as a teammate yelling a play or a coach calling to them from the sidelines, according to the study of nearly 1,000 participants, including approximately 500 Northwestern Division I athletes.
Kraus likens the phenomenon to listening to a DJ on the radio.
"Think of background electrical noise in the brain like static on the radio," Kraus said. "There are two ways to hear the DJ better: minimize the static or boost the DJ's voice. We found that athlete brains minimize the background 'static' to hear the 'DJ' better."
The study will be published Dec. 9 in the journal Sports Health.
"A serious commitment to physical activity seems to track with a quieter nervous system," Kraus said. "And perhaps, if you have a healthier nervous system, you may be able to better handle injury or other health problems."
The findings could motivate athletic interventions for populations that struggle with auditory processing. In particular, playing sports may offset the excessively noisy brains often found in children from low-income areas, Kraus said.
This is the latest study from the neural processing of sound in sports concussions and contact sports partnership, a five-year, National Institutes of Health-funded research collaboration between Brainvolts and Northwestern University Athletics, which launched last year. The study examined the brain health of 495 female and male Northwestern student athletes and 493 age- and sex-matched control subjects.
Kraus and her collaborators delivered speech syllables to study participants through earbuds and recorded the brain's activity with scalp electrodes. The team analyzed the ratio of background noise to the response to the speech sounds by looking at how big the response to sound was relative to the background noise. Athletes had larger responses to sound than non-athletes, the study showed.
Like athletes, musicians and those who can speak more than one language also have an enhanced ability to hear incoming sound signals, Kraus said. However, musicians' and multilinguals' brains do so by turning up the sound in their brain versus turning down the background noise in their brain.
"They all hear the 'DJ' better but the musicians hear the 'DJ' better because they turn up the 'DJ,' whereas athletes can hear the 'DJ' better because they can tamp down the 'static,'" Kraus said.

Even light alcohol consumption linked to higher cancer risk

In a study conducted in Japan, even light to moderate alcohol consumption was associated with elevated cancer risks. In the study published early online in CANCER, a peer-reviewed journal of the American Cancer Society, the overall cancer risk appeared to be the lowest at zero alcohol consumption.
Although some studies have linked limited alcohol consumption to lower risks of certain types of cancer, even light to moderate consumption has been associated with a higher risk of cancer overall. To study the issue in Japan, Masayoshi Zaitsu, MD, PhD, of The University of Tokyo and the Harvard T.H. Chan School of Public Health, and his colleagues examined 2005-2016 information from 33 general hospitals throughout Japan. The team examined clinical data on 63,232 patients with cancer and 63,232 controls matched for sex, age, hospital admission date, and admitting hospital. All participants reported their average daily amount of standardized alcohol units and the duration of drinking. (One standardized drink containing 23 grams of ethanol was equivalent to one 180-milliliter cup (6 ounces) of Japanese sake, one 500-milliliter bottle (17 ounces) of beer, one 180-milliliter glass (6 ounces) of wine, or one 60-milliliter cup (2 ounces) of whiskey.
Overall cancer risk appeared to be the lowest at zero alcohol consumption, and there was an almost linear association between cancer risk and alcohol consumption. The association suggested that a light level of drinking at a 10-drink-year point (for example, one drink per day for 10 years or two drinks per day for five years) would increase overall cancer risk by five percent. Those who drank two or fewer drinks per day had an elevated cancer risk regardless of how long they had consumed alcohol. Also, analyses classified by sex, drinking/smoking behaviors, and occupational class mostly showed the same patterns.
The elevated risk appeared to be explained by alcohol-related cancer risk across relatively common sites, including the colorectum, stomach, breast, prostate, and esophagus.

Adding 2-3 servings of fresh lean pork each week, the Mediterranean-Pork diet delivers cognitive benefits, while also catering to Western tastes, and ensuring much lower greenhouse-gas emissions than beef production

Barbecued, stir-fried or roasted, there's no doubt that Aussies love their meat. Consuming on average nearly 100 kilograms of meat per person per year, Australians are among the top meat consumers worldwide.
But with statistics showing that most Australians suffer from a poor diet, and red meat production adding to greenhouse-gas emissions, finding a balance between taste preferences, environmental protection, and health benefits is becoming critical.
Now, researchers from the University of South Australia can reveal that Aussies can have their health and eat meat too with a new version of the Mediterranean diet adapted for Australian palates.
Incorporating 2-3 serves (250g) of fresh lean pork each week, the Mediterranean-Pork (Med-Pork) diet delivers cognitive benefits, while also catering to Western tastes, and ensuring much lower greenhouse-gas emissions than beef production.
A typical Mediterranean diet includes extra virgin olive oil, fruits, vegetables, nuts, seeds, legumes, wholegrain breads, pastas and cereals, moderate consumption of fish and red wine, and low consumption of red meat, sweet and processed foods.
This study compared the cognitive effects of people aged 45-80 years and at risk of cardiovascular disease following a Med-Pork or a low-fat diet (often prescribed to negate risk factors for cardiovascular disease), finding that the Med-Pork intervention outperformed the low-fat diet, delivering higher cognitive processing speeds and emotional functioning, both of which are markers of good mental health.
UniSA researcher Dr Alexandra Wade says the new Med-Pork diet will provide multiple benefits for everyday Australians.
"The Mediterranean diet is widely accepted as the world's healthiest diet and is renowned for delivering improved cardiovascular and cognitive health, but in Western cultures, the red meat restrictions of the diet could make it hard for people to stick to," Dr Wade says.
"By adding pork to the Mediterranean diet, we're broadening the appeal of the diet, while also delivering improved cognitive function.
"This bodes well for our aging population, where age-associated diseases, such as dementia, are on the rise.
"Improving people's processing speed shows the brain is working well. So, in Australia, the Med-Pork diet is an excellent lifestyle intervention where dementia is one of the leading causes of disability and the second leading cause of death.
"Then, when you add the fact that pork production emits only a fraction of the greenhouse gases compared to beef, and the Med-Pork diet is really ticking all boxes -- taste, health and environment."
According to the World Health Organization (WHO), by 2050, the number of people aged 60 years and older will outnumber children younger than five years old, bringing common health concerns associated with ageing into the fore. Further WHO statistics shows that cardiovascular disease is the number 1 cause of death globally and that dementia is one of the major causes of disability and dependency among older people worldwide.
Dr Wade says the Mediterranean diet with lean pork is an effective adaption of a successful eating plan
"Put simply, a Mediterranean diet encourages healthy eating. It's a food-based eating pattern that, with pork, still delivers significant health benefits," Dr Wade says.
"We're hoping that more people will find this dietary pattern to be more in line with their accustomed eating patterns and therefore more adoptable.

Monday, December 9, 2019

Aspirin may no longer be effective as cardiovascular treatment

A new paper in Family Practice, published by Oxford University Press, found that the widespread use of statins and cancer screening technology may have altered the benefits of aspirin use. Researchers concluded that aspirin no longer provides a net benefit as primary prevention for cardiovascular disease and cancer.
Nearly half of adults 70 years and older have reported taking aspirin daily even if they don't have a history of heart disease or stroke. Overall, an estimated 40% of adults in the United States take aspirin for primary prevention of cardiovascular diseases, making it one of our most commonly used medications
Researchers conducted the first review of aspirin's role in cardiovascular prevention 30 years ago, reporting a reduction in risk for both fatal and non-fatal heart attacks. Subsequent reports also found a reduction in cancer deaths for patients taking aspirin for five or more years, but no reduction in cardiovascular related deaths or strokes, and consistently displayed a significant risk of major bleeding complications.
Most of these aspirin trials were set in Europe and the United States and recruited patients prior to 2000. Since then, cholesterol-lowering drugs have gone into widespread use, accompanied by better management of hypertension, less tobacco use, and widespread adoption of colorectal cancer screening.
Researchers compared these older studies with four recent large scale trials of aspirin. Broadly, participants in the newer trials resembled the contemporary population that would use aspirin for primary prevention. In comparison, they were older, somewhat less likely to smoke, and more likely to have type 2 diabetes than patients in the older trials.
Like older studies, the recent trials of aspirin for primary prevention found no mortality benefit and a significant increase in the risk of major haemorrhages. However, they failed to find evidence for the two important benefits of aspirin: a reduction in the risk of cancer deaths and a reduced risk of non-fatal heart attacks. For every 1000 patients who took aspirin for five years there were four fewer major cardiovascular events but 7 more episodes of major haemorrhage and no change to overall cardiovascular mortality.
With the widespread use of statins and population wide cancer screenings today, aspirin may no longer reduce the overall risk of cancer death or heart attack when given as primary prevention.
"The good news is that the incidence of cardiovascular disease and colorectal cancer are decreasing due to better control of risk factors and screening, but that also seems to reduce the potential benefit of aspirin."

Taking a baby aspirin every day to prevent a heart attack or stroke should no longer be recommended to patients who haven't already experienced one of these events.
That's according to a new study published in Family Practice.
Nearly one-quarter of Americans over the age of 40 have reported taking aspirin daily even if they don't have a history of heart disease or stroke.
That's a problem, says study author University of Georgia researcher Mark Ebell.
As a physician and epidemiologist at UGA's College of Public Health, Ebell's work evaluates the evidence underpinning clinical practice and health behaviors. The current recommendation for taking aspirin as the primary form of heart attack or stroke prevention is limited to adults aged 50 to 69 who have an increased cardiovascular risk.
"We shouldn't just assume that everyone will benefit from low-dose aspirin, and in fact the data show that the potential benefits are similar to the potential harms for most people who have not had a cardiovascular event and are taking it to try to prevent a first heart attack or stroke," said Ebell.
Aspirin was first found to reduce the risk of fatal and nonfatal heart attacks 30 years ago, and subsequent studies found evidence that aspirin may also reduce risk of stroke and colon cancer.
But aspirin use has always carried risks, said Ebell, namely bleeding in the stomach and brain.
More recent studies have begun to suggest that potential harms of taking aspirin may outweigh the benefits by today's medical standards.
"If you look back in the 1970s and '80s when a lot of these original studies were done, patients were not taking statin drugs to control cholesterol, their blood pressure was not as well controlled, and they weren't getting screenings for colorectal cancer," said Ebell.
Ebell and his colleague Frank Moriarty of the Royal College of Surgeons in Ireland compared aspirin studies using patient data from 1978 to 2002 to four large-scale aspirin trials occurring after 2005, when statin use and colorectal cancer screenings had become more widespread.
They found that for 1,000 patients treated for five years, there were four fewer cardiovascular events and seven more major hemorrhages. Ebell was particularly alarmed by the number of brain bleeds experienced by aspirin users.
"About 1 in 300 persons who took aspirin for five years experienced a brain bleed. That's pretty serious harm. This type of bleeding can be fatal. It can be disabling, certainly," he said. "One in 300 is not something that the typical doctor is going to be able to pick up on in their practice. That's why we need these big studies to understand small but important increases in risk."
Ebell cautions people who are concerned about their cardiovascular risk, but who haven't had a heart attack or stroke, to talk with their doctors about other ways to prevent a major event.
These days, he says, treatment for blood pressure, cholesterol and diabetes are more aggressive, and the rate of other risk factors like smoking has dropped.
"There are so many things that we're doing better now that reduce cardiovascular and colorectal cancer risk, which leaves less for aspirin to do," he said.

Thursday, December 5, 2019

Being active reduces risk of prostate cancer

Prostate cancer is the most common cancer in men in the UK , yet we still don't know all of its causes. The largest ever study to use genetics as a measurement for physical activity to look at its effect on prostate cancer, reveals that being more active reduces the risk of prostate cancer. Over 140,000 men were included in the study, of which, 80,000 had prostate cancer.
This new study, published in the International Journal of Epidemiology today [5 December], was led by the University of Bristol and co-funded by World Cancer Research Fund (WCRF) and Cancer Research UK (CRUK). It found that people with the variation in their DNA sequence that makes them more likely to be active, had a 51 per cent reduced risk of prostate cancer than people who did not have this particular variation. Importantly, the findings relate to overall physical activity, not just intense exercise.
WCRF's own evidence has already shown that being active can reduce the risk of bowel, breast and womb cancer, but the evidence of physical activity on prostate cancer was limited. But this large study, which uses genetics as a proxy measurement for physical activity, shows that being active may in fact have a large impact on prostate cancer risk. To date there has been little evidence of ways to reduce prostate cancer risk other than maintaining a healthy weight.
Dr Sarah Lewis, Senior Lecturer in Genetic Epidemiology at Bristol Medical School: Population Health Sciences, and lead author of the research, said: "This study is the largest-ever of its kind which uses a relatively new method that complements current observational research to discover what causes prostate cancer. It suggests that there could be a larger effect of physical activity on prostate cancer than previously thought, so will hopefully encourage men to be more active."
Dr Anna Diaz Font, Head of Research Funding at WCRF, said: "Up till now, there has only been limited evidence of an effect of physical activity on prostate cancer. This new study looked at the effect of 22 risk factors on prostate cancer, but the results for physical activity were the most striking. This will pave the way for even more research, where similar methods could be applied to other lifestyle factors, to help identify ways men can reduce their risk of prostate cancer."
This new type of study that combines genetics, lifestyle and cancer risk, supports previous evidence from observational studies that being active can reduce the risk of cancer.

Moderate intensity physical activity associated with lower risk of diabetes

Daily exercise at moderate intensity is associated with beneficial levels of a hormone that may lower risk of diabetes, according to a study published in Endocrine Connections. Men who were physically active at moderate intensity for 30 minutes a day, released higher levels of a hormone that reduces appetite and blood sugar levels. These findings may suggest that even lower intensity of daily habitual physical activity could help prevent metabolic diseases such as diabetes.
A sedentary lifestyle can lead to metabolic complications such as heart disease, diabetes and obesity, and is the second most preventable cause of premature death after smoking. Physical activity at any intensity is known to improve health and prolong lifespan. Glucagon-like peptide-1 (GLP-1) is an appetite-inhibiting hormone that stimulates insulin secretion and lowers blood sugar levels. Previous studies suggest that exercise may affect GLP-1 secretion but have been inconclusive, and the effect of daily lower intensity exercise, including regular activity such as walking, remains uncertain.
In this study, PhD student Charlotte Janus and Professor Signe Torekov from the University of Copenhagen, together with researchers from Steno Diabetes Center, investigated the association between normal, daily, physical activity and GLP-1 secretion in an overweight population of 703 men and 623 women. Participants' heart rates were monitored as they carried out their normal daily lives to determine their daily activity intensity, ranging from sedentary to vigorous. GLP-1 levels were measured before and after drinking glucose to assess how physical activity may affect secretion of the hormone. Results from the study indicated that moderate intensity exercise, for just 30 minutes a day, increased GLP-1 levels in men, but not in women, who were on average active for only 20 minutes a day.
PhD student Janus comments, "Our study is encouraging as the results suggest that daily activity, even at a relatively low intensity and for a short amount of time such as brisk walking, gardening and playing with grandchildren, could improve appetite and blood glucose regulation."
"Greater GLP-1 hormone levels decrease both hunger sensation and blood sugar and may therefore decrease the risk of both obesity and type 2 diabetes," Professor Torekov adds.
"The association between physical activity and GLP-1 secretion may only be seen in men due to physiological differences and generally lower activity levels for women in this study. It may also indicate that a certain minimum level of physical activity is required for there the positive effect on GLP-1 levels, however more studies are required to confirm this."
These findings suggest that increasing daily activity to at least 30 minutes a day, such as walking rather than taking a bus, could lower risk of diabetes and improve overall metabolic health. Low-intensity activity is much more achievable than high-intensity exercise, which can be time consuming or too physically demanding for some people.
"If you don't have the time or ability to do high-intensity exercise, increasing your daily physical activity level may still affect GLP-1 production and have positive impacts on your health," PhD student Janus recommends.
However, importantly these findings are based on a cross-sectional study that shows only associations between physical activity and GLP-1 levels, and not direct causality. PhD student Janus and Professor Torekov now plan to confirm these findings by investigating the direct effects of moderate intensity activity on GLP-1 secretion.

Mindfulness training may help lower blood pressure

As the leading cause of death in both the United States and the world, heart disease claims nearly 18 million lives every year, according to the World Health Organization.
Many of these deaths are due to hypertension, or abnormally high blood pressure, and could be prevented through medication or lifestyle changes such as healthier eating, weight loss and regular exercise -- but behavior change is often challenging. That's where mindfulness may be useful, says Eric Loucks, an associate professor of epidemiology, behavioral and social sciences, and medicine at Brown University.
"We know enough about hypertension that we can theoretically control it in everybody -- yet in about half of all people diagnosed, it is still out of control," said Loucks, lead author of a new study published in PLOS One. "Mindfulness may represent another approach to helping these people bring their blood pressure down, by allowing them to understand what's happening in their minds and bodies."
Loucks directs the Mindfulness Center at Brown's School of Public Health, which aims to help scientists, health care providers and consumers better understand whether particular mindfulness interventions work, for which health concerns and for which patients.
For the study, Loucks and a team of researchers developed a nine-week customized Mindfulness-Based Blood Pressure Reduction (MB-BP) program for 43 participants with elevated blood pressure and followed up with them after one year. The program aimed to use mindfulness techniques to enhance attention control, emotion regulation and self-awareness of both healthy and unhealthy habits, thereby diminishing some of the risk factors associated with elevated blood pressure -- and it appears to have worked, the study shows.
After undergoing mindfulness training, participants exhibited significant improvements in self-regulation skills and significantly reduced blood pressure readings. Participants who had not been adhering to the American Heart Association's guidelines for salt and alcohol intake and physical activity improved in those areas as well. The positive effects were still present at the one-year follow-up and were most pronounced for participants who enrolled with stage 2 uncontrolled hypertension (i.e., a systolic blood pressure equal to or greater than 140 mmHg). These participants experienced a mean 15.1-mmHg reduction in blood pressure.
The program, Loucks said, was a "deliberately multimodal intervention," intentionally combining mindfulness training with other strategies used to reduce blood pressure, such as encouraging participants to continue taking prescribed anti-hypertensive medications and educating participants about habits that contribute to elevated blood pressure.
"Future trials could involve a dismantling study, where we would take out some of the health education, for example, and see if mindfulness training still had significant effects," Loucks said. "That's certainly something we're looking at doing in the long term. But mindfulness training is usually designed to be integrated with standard medical care."
He added that a follow-up study is currently underway: a randomized control trial of the MB-BP program that contains more than 200 participants.
"I hope that these projects will lead to a paradigm shift in terms of the treatment options for people with high blood pressure," Loucks said.
For people who don't face challenges in maintaining a healthy blood pressure, MB-BP training may be an effective preventive tool, he added. Within this initial study, more than 80 percent of participants had hypertension (130 systolic over 85 diastolic or higher), while the remainder had elevated blood pressure (at least 120 over 80), and the average participant was 60 years old. But Loucks supports using mindfulness techniques for those across all age groups and blood pressure levels.
"The hope is that if we can start mindfulness training early in life, we can promote a trajectory of healthy aging across the rest of people's lives," he said. "That will reduce their chances of getting high blood pressure in the first place."

Older adults who 'train' for a major operation spend less time in the hospital

Older adults who "train" for a major operation by exercising, eating a healthy diet, and practicing stress reduction techniques preoperatively have shorter hospital stays and are more likely to return to their own homes afterward rather than another facility, compared with similar patients who do not participate in preoperative rehabilitation, according to research findings. The new study, which appears as an "article in press" on the Journal of the American College of Surgeons website in advance of print, evaluated a home-based program of preoperative rehabilitation--called prehabilitation--for Michigan Medicare beneficiaries.

The researchers also reported an association between prehabilitation and lower total insurance payments for all phases of care.

"Prehabilitation is good for patients, providers, and payers," said study coauthor Michael J. Englesbe, MD, FACS, a liver transplant surgeon at the University of Michigan, Ann Arbor. "We believe every patient should train for a major operation. It's like running a 5K race: You have to prepare."

Involving physical and lifestyle changes, prehabilitation, or "prehab," optimizes a patient's well-being and ability to withstand the stress of undergoing an operation, Dr. Englesbe said. Past studies show that prehabilitation lowers the rate of postoperative complications and speeds the patient's return to their normal functioning, among other advantages.*

"Prehab has been gaining momentum over the past 10 years. More surgeons and other clinicians are appreciating its benefits," Dr. Englesbe said. "However, the feasibility and value of broad implementation of prehabilitation outside the research environment were unknown."

For this new study researchers tested the real-world effectiveness and cost savings of prehabilitation. Patients underwent diverse cardiothoracic (chest/heart) and abdominal operations at 21 hospitals in Michigan that participated in a statewide prehabilitation program called the Michigan Surgical & Health Optimization Program (MSHOP). Patients' surgeons referred them to MSHOP if they were at high risk of postoperative complications, Dr. Englesbe, program co-developer and director, said.

Physical and psychological preparation
MSHOP involved a home-based walking program in which surgical patients tracked their steps using a pedometer and received daily reminders and feedback through phone, email, or text messages. Program participants received educational materials on nutrition, relaxation techniques, and smoking cessation as well. They also practiced using an incentive spirometer, a medical device that helps patients keep their lungs healthy after an operation.

Included in the study were 523 Medicare patients who participated in MSHOP for at least one week before an inpatient operation and filed Medicare claims between 2014 and 2017, according to the article. For comparison, the researchers used Medicare claims data during the same period to identify 1,046 matched controls: patients with similar demographic characteristics and coexisting illnesses who had the same operation at the same hospital but did not take part in prehabilitation. The average age of patients and controls was 70 years.

Participation in MSHOP ranged from 11 to 33 days, the researchers reported. Of the participants, 62 percent were reportedly "engaged" in the prehabilitation program, defined as recording step counts three or more times per week for most of the program. Thirty-nine patients (7.5 percent) asked to be removed from the program, but they remained in the statistical data analysis. For both groups, the study authors analyzed data for the hospitalization and 90 days afterward.

Prehabilitation leads to better outcomes
Participation in prehabilitation was significantly associated with several improved outcomes that are important to patients or insurers, according to the researchers:
  • The hospital length of stay was shorter by one day, with a median (middle value) of six days for participating patients versus seven days for controls, who received no prehabilitation.
  • Program participants were more likely to be discharged from the hospital to home: 65.6 percent versus 57 percent of controls.
  • Medicare paid nearly $3,200 less in total payments for both hospital and posthospital care (what Medicare calls an "episode of care") for patients who underwent prehabilitation than for controls: $31,641 versus $34,837.
  • Insurance payments were especially lower among patients for posthospital care, including skilled nursing facility ($941 versus $1,566 for controls) and home health care ($829 versus $960 for controls).
"Every patient scheduled for a major operation--not just those at high risk--should ask their surgeon for a prehabilitation program," Dr. Englesbe recommended.

Although the study did not evaluate patient satisfaction with prehabilitation, Dr. Englesbe said patients at his medical center who completed MSHOP described their surgical experience positively, using words such as "empowering." Some patients requested MSHOP when they required another operation, he said.

Dr. Englesbe said he hopes that prehabilitation will become the standard of surgical care in Michigan.

Nationwide, prehabilitation is an area of focus for the American College of Surgeons' Strong for Surgery program, which promotes evidence-based practices to boost preoperative health. Prehab also is part of the College's new Geriatric Surgery Verification Program standards, developed to optimize surgical care for older adults, and now enrolling hospitals nationally.

A strong link between non-HDL cholesterol levels and long-term risk for cardiovascular disease in people aged under 45 years

  • Study is the most comprehensive analysis of long-term risk for cardiovascular disease related to non-high-density lipoprotein (non-HDL) cholesterol - including almost 400,000 people from 19 countries who were followed for up to 43.5 years (median 13.5 years follow-up) between 1970 to 2013.
  • This longer-term evidence may be particularly important in people aged under 45 years.
  • Depending on cholesterol level and number of cardiovascular risk factors, men and women aged under 45 years have a 12-43% or 6-24% risk (respectively) of having fatal or non-fatal heart disease or stroke by the age of 75 years.
  • If non-HDL cholesterol levels were halved, women and men younger than 45 years with starting levels of non-HDL cholesterol between 3.7-4.8 mmol/litre and who had two additional cardiovascular risk factors could reduce their risk from around 16% to 4%, and from around 29% to 6%, respectively.
The most comprehensive analysis of its kind suggests that there is a strong link between non-HDL cholesterol levels and long-term risk for cardiovascular disease in people aged under 45 years, not just at older ages.
The observational and modelling study which used individual-level data from almost 400,000 people, published in The Lancet, extends existing research because it suggests that increasing levels of non-HDL cholesterol may predict long-term cardiovascular risk by the age of 75 years. Past risk estimates of this kind are based on 10-year follow-up data.
For example, women with non-HDL cholesterol levels between 3.7-4.8 mmol/litre, who were younger than 45 years, and had at least two additional cardiovascular risk factors, had a 16% probability of experiencing a cardiovascular disease event by the age of 75 years (ie, 16 in 100 women with these characteristics were predicted to have a cardiovascular event by the age of 75 years). For women aged 60 or over with the same characteristics, the estimated risk was 12%.
For men with the same characteristics, the estimated risk for those aged under 45 years was 29%, and was 21% for those aged 60 years or more.
"This increased risk in younger people could be due to the longer exposure to harmful lipids in the blood. The risk may also appear larger compared to older ages because people aged 60 years and older in our study had not developed cardiovascular disease up to this age, so they may be healthier than others of their age who were excluded from the study because they had had cardiovascular disease," says Professor Barbara Thorand, German Research Center for Environmental Health, Germany. [1]
The amount of non-HDL cholesterol [2] and low-density lipoproteins (LDL) in the blood are accepted as causal risk factors for cardiovascular disease, and play a significant part in predicting a person's risk of developing cardiovascular disease.
The authors say that intervening early and intensively to reduce non-HDL cholesterol levels during the lifespan could potentially reverse early signs of atherosclerosis. However, considerable uncertainty exists about the extent to which slightly increased or apparently normal cholesterol levels affect lifetime cardiovascular risk, and about which levels should be used to make treatment recommendations, particularly in young people.
In the study, the authors used individual-level data from almost 400,000 people from 38 studies from Europe, Australia and North America. The participants had no cardiovascular disease at the start of the study and were followed for up to 43.5 years (median 13.5 years follow-up) for the occurrence of a fatal or non-fatal coronary heart disease event or ischaemic stroke.
Using their data, the authors assessed and confirmed the long-term association between cholesterol levels and cardiovascular event risk. They then used this data in a model to estimate the probability of a cardiovascular event by the age of 75 years for people aged 35-70 years, according to a person's gender, non-HDL cholesterol levels, age, and cardiovascular disease risk factors (such as smoking status, diabetes, BMI, systolic blood pressure, and antihypertensive medication). The model also estimated how much risk could be reduced if non-HDL cholesterol levels were halved (the authors note that the 50% reduction was hypothetical and not based on specific estimates or treatments).
During follow-up, there were 54,542 fatal or non-fatal cases of heart disease and stroke.
Looking at data for all age groups and both sexes, the authors found that the risk for a cardiovascular event decreased continuously with decreasing non-HDL levels and the risk was lowest for those individuals with the lowest non-HDL levels (classified as below 2.6 mmol non-HDL cholesterol per litre in the study). [3]
Using the model to estimate the risk of a cardiovascular event by the age of 75 years for different age groups, the authors found that the highest long-term risks of cardiovascular disease were seen in individuals younger than 45 years of age.
For example, women with non-HDL cholesterol levels between 3.7-4.8 mmol/litre, who were younger than 45 years, and had at least two additional cardiovascular risk factors, had an estimated 16% probability of experiencing a cardiovascular disease event by the age of 75 years (ie, 16 in 100 women with these characteristics were predicted to have a cardiovascular event by the age of 75 years). For women aged 60 or over with the same characteristics, the estimated risk was 12%. For men with the same characteristics, the estimated risk for those aged under 45 years was 29%, and was 21% for those aged 60 years or more.
Using the model to estimate how much cardiovascular disease could be reduced if a person halved their non-HDL cholesterol levels, the authors found that for all non-HDL cholesterol levels, the greatest reductions were seen in the youngest age group compared with older age groups.
For example, in people younger than 45 years with levels of 3.7-4.8 mmol/litre and with at least two risk factors, they estimated that the long-term risk of cardiovascular disease could hypothetically be reduced from 16% to 4% in women, and from 29% to 6% in men. For people with the same characteristics aged 60 years or over, risk could potentially be reduced from 12% to 6% in women and from 21% to 10% in men.
"Our estimates suggest that halving non-HDL cholesterol levels may be associated with reduced risk of cardiovascular events by the age of 75 years, and that this reduction in risk is larger the sooner cholesterol levels are reduced. The risk scores currently used in the clinic to decide whether a person should have lipid-lowering treatment only assess the risk of cardiovascular disease over 10 years, and so may underestimate lifetime risk, particularly in young people," says Professor Stefan Blankenberg, German Center for Cardiovascular Research, Germany. [1]
"In lieu of needed clinical trial results investigating the benefits of long-term lipid-lowering therapy in people younger than 45, this study may provide helpful insights on the benefits of lipid-lowering therapy as primary prevention from an earlier age. However, future research is needed to understand whether intervention in young people with a high lifetime risk, but low 10-year risk, would have more benefits than later intervention," he concludes. [1]
Professor Frank Kee, Queens University Belfast, UK, adds: "Further research is also needed on how useful lifetime absolute risk estimates are for motivating behaviour change among otherwise healthy young people, and whether titrating any intervention dose according to a non-HDL target would be more effective than to a target of overall life-time risk." [1]
The authors note some limitations within their study, including that their study results may not be generalisable to other regions or racial and ethnic groups as the study was based on data from people of European ancestry from high-income countries.
The authors used data about the participants' non-HDL cholesterol levels when they entered the study only, and so could not account for changes in cholesterol levels. However, they note that non-HDL cholesterol levels in young people are generally stable over the 30-year life course. They also could not account for participants beginning to take lipid-lowering therapy during the study, but adjusted cholesterol levels for people who were already taking lipid-lowering therapy at the start of the study.
Lastly, they note that their modelled 50% reduction posits that the effects of treatment apply over a longer period (30 years) than has been studied in clinical trials (around seven years), and note that real-world benefits of lipid-lowering therapies like statins are probably lower than the cholesterol reductions seen in trials because of sub-optimal adherence and side effects.
Writing in a linked Comment, Professor Jennifer G Robinson, University of Iowa, USA, also says that the size of this reduction is the main limitation of the analysis, as only long-term lipid-lowering treatment is likely to achieve a reduction of this size, but the existing evidence for these drugs does not assess decades-long treatment, meaning that the risk of adverse events - which would alter the benefit-to-risk ratio - are unclear.
She writes: "The novelty of Brunner and colleagues' findings arises from projecting the effect of beginning cholesterol-lowering therapy early in life. Such therapy could reduce the lifetime risk of atherosclerotic cardiovascular disease in patients with increased concentrations of non-HDL and LDL cholesterol, especially when risk is further amplified by the presence of comorbid factors. These individuals could be at much lower 10-year risk thresholds of atherosclerotic cardiovascular disease than are currently recommended for consideration of statin therapy. Lowering cholesterol with more intensive therapy is also supported by findings that generic statins are cost-saving or highly cost-effective even for primary prevention in patients at low risk of cardiovascular disease."

Eating within 10-hour window may help stave off diabetes, heart disease

Metabolic syndrome is the name for a group of risk factors, such as high blood pressure and cholesterol levels, that increase the risk for adverse health issues, from heart disease and diabetes to stroke. Eating healthier, getting more exercise and taking prescribed medications when needed are common remedies but often prove insufficient to fully managing risks.
In a recent collaborative effort, researchers from University of California San Diego School of Medicine and the Salk Institute for Biological Studies reported a form of intermittent fasting, called time-restricted eating, improved the health of study participants who had been diagnosed with metabolic syndrome.
The pilot study, published online in the December 5, 2019 edition of Cell Metabolism, found that when participants restricted their eating to 10 hours or less over a period of 12 weeks, they lost weight, reduced abdominal fat, lowered blood pressure and cholesterol and enjoyed more stable blood sugar and insulin levels.
"As a cardiologist, I find it is very hard to get patients with prediabetes or metabolic syndrome to make lasting and meaningful lifestyle changes," said Pam Taub, MD, co-corresponding author and associate professor of medicine at UC San Diego School of Medicine and cardiologist at the Cardiovascular Institute at UC San Diego Health. "There is a critical window for intervention with metabolic syndrome. Once people become diabetic or are on multiple medications, such as insulin, it's very hard to reverse the disease process.
"Metabolism is closely linked with circadian rhythms, and knowing this, we were able to develop an intervention to help patients with metabolic syndrome without decreasing calories or increasing physical exercise."
Time-restricted eating (eating all calories within a consistent 10-hour window) allows individuals to eat in a manner that supports their circadian rhythms and their health. Circadian rhythms are the 24-hour cycles of biological processes that affect nearly every cell in the body. Erratic eating patterns can disrupt this system and induce symptoms of metabolic syndrome, including increased abdominal fat and abnormal cholesterol or triglycerides.
"Time-restricted eating is a simple dietary intervention to incorporate, and we found that participants were able to keep the eating schedule," said Satchin Panda, PhD, co-corresponding author and professor in Salk's Regulatory Biology Laboratory. "Eating and drinking everything (except water) during a 10-hour window allows your body to rest and restore for 14 hours at night. Your body can also anticipate when you will eat, so it can prepare the body to optimize metabolism."
The study involved 19 participants diagnosed with metabolic syndrome, with 16 taking at least one medication, like a statin. Participants used an app created by Panda called myCircadianClock to log when and what they ate during an initial two-week baseline period followed by three months of 10-hour time-restricted eating per day. They were told they could decide what time to eat and how much to eat as long as all food consumption occurred within a 10-hour window.
At the end of the 12 weeks, participants averaged a 3 percent reduction in weight and body mass index (BMI) and a 4 percent reduction in abdominal/visceral fat. Many also experienced reductions in cholesterol and blood pressure and improvements in fasting glucose. Seventy percent of participants reported an increase in sleep satisfaction or in the amount they slept. "Patients also reported that they generally had more energy, and some were able to have their medications lowered or stopped after completing the study," said Taub.
More than two-thirds of participants continued with time-restricted eating for up to a year after the study concluded -- at least part of the time. "Adapting this 10-hour time-restricted eating is also a cost-effective method for reducing symptoms of metabolic syndrome and improving health," said Panda. "By delaying the onset of diabetes by even one year in a million people with prediabetes, the intervention could save roughly $9.6 billion dollars in health care costs."
The researchers are currently conducting another clinical trial to examine the benefits of time-restricted eating in a larger group of more than 100 participants with metabolic syndrome. The study examines additional measures that will help the researchers investigate changes in body composition and muscle function.
"Knowing how to optimize circadian rhythms could lead to a new treatment option for metabolic syndrome patients with life-altering diseases," said Taub.

Tuesday, December 3, 2019

Scientists discover multiple mechanisms at work in widely-used diabetes drug metformin

Salk Institute
Metformin is the most commonly prescribed type 2 diabetes drug, yet scientists still do not fully know how it works to control blood sugar levels. In a collaborative effort, researchers from the Salk Institute, The Scripps Research Institute and Weill Cornell Medical College have used a novel technology to investigate why it functions so well. The findings, which identified a surprising number of biochemical "switches" for various cellular processes, could also explain why metformin has been shown to extend health span and life span in recent studies. The work was published in Cell Reports on December 3, 2019.
"These results provide us with new avenues to explore in order to understand how metformin works as a diabetes drug, along with its health-span-extending effects," says Professor Reuben Shaw, co-corresponding author of the paper and the director of Salk's NCI-designated Cancer Center. "These are pathways that neither we, nor anyone else, would have imagined."
Previously, the only biochemical pathway that was known to be activated by metformin was the AMPK pathway, which Shaw discovered stalls cell growth and changes metabolism when nutrients are scarce, as can occur in cancer. But the scientists believed more pathways than AMPK might be involved.
The scientists developed a novel screening platform to examine kinases, the proteins that transfer phosphate groups, which are critical on/off switches in cells and can be rapidly flipped by metformin. Using this technology, the researchers were able to decode hundreds of regulatory "switch-flipping" events that could affect healthy aging.
"Being mentored by John Yates, one of the top mass spectrometry investigators in the world, and Reuben Shaw, an expert in the field of metabolism, enabled me to both develop and apply a novel technology to a critical biological question: What pathways are regulated by metformin in the liver?" says Ben Stein, first author and postdoctoral associate at Weill Cornell Medical College.
The results revealed that metformin turns on unexpected kinases and pathways, many independent of AMPK. Two of the activated kinases are called Protein Kinase D and MAPKAPK2. These kinases are poorly understood, but are known to have some relation to cellular stress, which could connect them to the health-span- and life-span-extending effects observed in other studies. In fact, metformin is currently being tested in multiple large-scale clinical trials as a health-span- and life-span-extending drug, but the mechanism for how metformin could affect health and aging has not been clear. The current study indicates that Protein Kinase D and MAPKAPK2 may be two players in providing these therapeutic effects, and identifies new targets and cellular processes regulated by AMPK that may also be critical to metformin's beneficial effects.
"We never imagined these two kinases would have anything to do with metformin," says Shaw, holder of the William R. Brody Chair. "The results broaden our understanding of how metformin induces a mild stress that triggers sensors to restore metabolic balance, explaining some of the benefits previously reported such as extended healthy aging in model organisms taking metformin. The big questions now are what targets of metformin can benefit the health of all individuals, not just type 2 diabetics."
Next, the researchers plan to examine the new signaling pathways they discovered in more detail to better understand the beneficial effects of metformin.

Aspirin can be considered a possible clinical option to other, more costly treatment and preventive options for migraines

According to a new report in The American Journal of Medicine, published by Elsevier, aspirin can be considered an effective and safe option to other, more expensive medications to treat acute migraines as well as prevent recurrent attacks. A review of randomized evidence suggests efficacy and safety of high dose aspirin in doses from 900 to 1,300 milligrams taken at the onset of acute symptoms. The data also support a lower dose of from 81 to 325 milligrams as a possible preventive option.
"Aspirin provides a possible clinical option for primary healthcare providers to relieve the debilitating symptoms of acute migraine headaches and prevent recurrent attacks. Aspirin's side effect profile and low cost may also favour its use," noted senior author Charles H. Hennekens, MD, DrPH, the first Sir Richard Doll Professor & Senior Academic Advisor to the Dean of the Charles E. Schmidt College of Medicine at Florida Atlantic University, Boca Raton, FL, USA. The investigators reviewed the randomized evidence for high dose aspirin in treatment and low dose aspirin in prevention of migraine headaches.
Migraine headache is the third most common disease in the world affecting about one in seven people. More prevalent than diabetes, epilepsy, and asthma combined, migraine headaches are among the most common and potentially debilitating disorders encountered by primary healthcare providers. Migraines are also associated with an increased risk of stroke. There are effective prescription medications available to treat acute migraine headaches as well as to prevent recurrent attacks. Nonetheless, in the United States many patients are not adequately treated for reasons that include limited access to healthcare providers, lack of health insurance, or high co-pays, which make expensive medications of proven benefit unaffordable. The rates of uninsured (or underinsured) have been estimated to be 8.5 percent nationwide and 13 percent in Florida. Furthermore, for all patients, the prescription drugs may be poorly tolerated or contraindicated.
Professor Hennekens mused that, "If aspirin were only half as effective, 10 times more expensive, and available by prescription, then perhaps patients and, possibly some of their healthcare providers, would take it more seriously."
"Despite the fact that aspirin is an over-the-counter drug," Dr. Hennekens cautioned, "as is the case for any drug used long term, it should be prescribed by a healthcare provider."
Joseph S. Alpert, MD, Editor-in-Chief of The American Journal of Medicine and Professor of Medicine, University of Arizona Department of Medicine, Tucson, AZ, USA, commented in an accompanying editorial, "My take home message from this thoughtful and carefully researched review is that physicians should always try the simple and inexpensive high dose aspirin regimen as the initial therapeutic attempt for migraine headache control. If aspirin works to abort or ameliorate the headaches, then it should be tried as a prophylactic measure to see if it can prevent the occurrence of these debilitating headaches. Hopefully, this would lead to less disability and loss of employment time for these patients who are so common in the US and throughout the world."