Thursday, March 15, 2018

Coffee affects cannabis and steroid systems

It's well known that a morning cup of joe jolts you awake. But scientists have discovered coffee affects your metabolism in dozens of other ways, including your metabolism of steroids and the neurotransmitters typically linked to cannabis, reports a new study from Northwestern Medicine.

In a study of coffee consumption, Northwestern scientists were surprised to discover coffee changed many more metabolites in the blood than previously known. Metabolites are chemicals in the blood that change after we eat and drink or for a variety of other reasons.

The neurotransmitters related to the endocannabinoid system -- the same ones affected by cannabis -- decreased after drinking four to eight cups of coffee in a day. That's the opposite of what occurs after someone uses cannabis. Neurotransmitters are the chemicals that deliver messages between nerve cells.

Cannabinoids are the chemicals that give the cannabis plant its medical and recreational properties. The body also naturally produces endocannabinoids, which mimic cannabinoid activity.

In addition, certain metabolites related to the androsteroid system increased after drinking four to eight cups of coffee in a day, which suggests coffee might facilitate the excretion or elimination of steroids. Because the steroid pathway is a focus for certain diseases including cancers, coffee may have an effect on these diseases as well.

"These are entirely new pathways by which coffee might affect health," said lead author Marilyn Cornelis, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine. "Now we want to delve deeper and study how these changes affect the body."

Little is known about how coffee directly impacts health. In the new study, Northwestern scientists applied advanced technology that enabled them to measure hundreds of metabolites in human blood samples from a coffee trial for the first time. The study generates new hypotheses about coffee's link to health and new directions for coffee research.

The paper will be published March 15 in the Journal of Internal Medicine.

Drinking lots of coffee for science
In the three-month trial based in Finland, 47 people abstained from coffee for one month, consumed four cups a day for the second month and eight cups a day for the third month. Cornelis and colleagues used advanced profiling techniques to examine more than 800 metabolites in the blood collected after each stage of the study.

Blood metabolites of the endocannabinoid system decreased with coffee consumption, particularly with eight cups per day, the study found.

The endocannabinoid metabolic pathway is an important regulator of our stress response, Cornelis said, and some endocannabinoids decrease in the presence of chronic stress.

"The increased coffee consumption over the two-month span of the trial may have created enough stress to trigger a decrease in metabolites in this system," she said. "It could be our bodies' adaptation to try to get stress levels back to equilibrium."

The endocannabinoid system also regulates a wide range of functions: cognition, blood pressure, immunity, addiction, sleep, appetite, energy and glucose metabolism.

"The endocannabinoid pathways might impact eating behaviors," suggested Cornelis, "the classic case being the link between cannabis use and the munchies."

Coffee also has been linked to aiding weight management and reducing risk of type 2 diabetes.

"This is often thought to be due to caffeine's ability to boost fat metabolism or the glucose-regulating effects of polyphenols (plant-derived chemicals)," Cornelis said. "Our new findings linking coffee to endocannabinoids offer alternative explanations worthy of further study."

It's not known if caffeine or other substances in coffee trigger the change in metabolites.


Omega-3 levels better predictors of death risk than serum cholesterol

Study shows omega-3 levels are better predictors of risk for death than serum cholesterol
A recent study published in the Journal of Clinical Lipidology looked at the value of measuring blood levels of EPA and DHA omega-3 fatty acids to assess an individual's risk for developing certain diseases. In this new report from Harris and colleagues, the "Omega-3 Index" (the EPA+DHA content of red blood cell membranes) was measured in 2500 participants in the Offspring cohort of the Framingham Heart Study. (This group is largely made up of the children of the original Framingham study which began in 1948.) The results showed that the risk for death from any cause was reduced by about 33% comparing the lowest Omega-3 Index participants to the highest.

All of the individuals in the present study were free of known cardiovascular disease (CVD) at baseline. The researchers primarily focused on total mortality (death from any cause) as an endpoint, but also tracked death from CVD, cancer and other causes. In addition, they reported the associations between Omega-3 Index levels and a risk for any CVD event - fatal or not, heart attack or stroke. The population was 66 years of age at baseline and there were a few more females than males. The study followed these individuals for disease outcomes until about age 73. The results were statistically adjusted for a wide variety of factors that could influence the outcomes.

According to the study, which was funded by the National Institutes of Health (NIH), a higher Omega-3 Index was associated with a lower risk for total CVD events, total coronary heart disease events, and total strokes. The category most strongly associated with the Omega-3 Index was non-CV, non-cancer deaths - deaths from all other causes. This would suggest a wide spectrum of beneficial actions of EPA and DHA in the body that are not just linked with one pathological process (like plaque build up in arteries).

The link between higher omega-3 blood levels and lower risk for death has been reported in at least three other studies, but what was novel about this most recent study from Framingham was a comparison the authors did between serum cholesterol and the Omega-3 Index, two "risk factors" for heart disease. "We all know that the serum cholesterol level is a major risk factor for CHD, and since the latter is a major cause of death in the Western world, it would be reasonable to expect that a high cholesterol level would portend higher risk for premature death," said lead author Dr. William Harris.

"This did not turn out to be the case here. When baseline serum cholesterol levels were substituted for the Omega-3 Index in the same multi-variable models, the former was not significantly associated with any of the tracked outcomes whereas the latter was related to 4 of the 5 outcomes assessed." Future studies are needed to try to replicate this finding and to determine if it is time to begin including the Omega-3 Index in routine blood screens along with cholesterol and glucose.

Wednesday, March 14, 2018

Physically fit women nearly 90 percent less likely to develop dementia

Women with high physical fitness at middle age were nearly 90 percent less likely to develop dementia decades later, compared to women who were moderately fit, according to a study published the March 14, 2018, online issue of Neurology®, the medical journal of the American Academy of Neurology. The study measured the women's cardiovascular fitness based on an exercise test.  
When the highly fit women did develop dementia, they developed the disease an average of 11 years later than women who were moderately fit, or at age 90 instead of age 79.

"These findings are exciting because it's possible that improving people's cardiovascular fitness in middle age could delay or even prevent them from developing dementia," said study author Helena Hörder, PhD, of the University of Gothenburg in Gothenburg, Sweden. "However, this study does not show cause and effect between cardiovascular fitness and dementia, it only shows an association. More research is needed to see if improved fitness could have a positive effect on the risk of dementia and also to look at when during a lifetime a high fitness level is most important."

For the study, 191 women with an average age of 50 took a bicycle exercise test until they were exhausted to measure their peak cardiovascular capacity. The average peak workload was measured at 103 watts. A total of 40 women met the criteria for a high fitness level, or 120 watts or higher. A total of 92 women were in the medium fitness category; and 59 women were in the low fitness category, defined as a peak workload of 80 watts or less, or having their exercise tests stopped because of high blood pressure, chest pain or other cardiovascular problems.

Over the next 44 years, the women were tested for dementia six times. During that time, 44 of the women developed dementia. Five percent of the highly fit women developed dementia, compared to 25 percent of moderately fit women and 32 percent of the women with low fitness. The highly fit women were 88 percent less likely to develop dementia than the moderately fit women.
Fitness level on test Dementia
High 5%
Medium 25%
Low 32%
Could not finish test 45%

Among the women who had to stop the exercise test due to problems, 45 percent developed dementia decades later.

"This indicates that negative cardiovascular processes may be happening in midlife that could increase the risk of dementia much later in life," Hörder said.

Limitations of the study include the relatively small number of women involved, all of whom were from Sweden, so the results may not be applicable to other populations, Hörder said. Also, the women's fitness level was measured only once, so any changes in fitness over time were not captured.

Tuesday, March 13, 2018

Older adults with small social networks less likely to get cataract surgery

Writing in JAMA Ophthalmology, researchers at the University of Michigan Kellogg Eye Center link such networks with the likelihood of older adults getting cataract surgery - a procedure with broad implications for health.

Not only can family motivate older adults to take care of their fading vision, but also family members can help them get the care they need.

"It may get to a point that it takes people around them to speak up about their changing vision," says study author Brian Stagg, M.D., a Kellogg ophthalmologist and health services researcher at the University of Michigan.

In observations of 9,760 adults older than 65 with Medicare benefits, those with none, one or two family members had 40-percent lower odds of receiving cataract surgery than adults with three or more family members. Data came from the National Health and Aging Trends Study.
The study by Kellogg Eye Center is consistent with a trend in health research that examines the impact of social isolation on health.

"A nuanced understanding of the impact of social support networks is important to develop as we implement strategies to improve access to cataract surgery for a rapidly growing older population," says Stagg.

Primary care doctors and ophthalmologists may need to ask older adults if transportation and support is available after the procedure. A social worker could help navigate care, too, authors say.
In the study, friends, spouses or partners did not influence the decision to have cataract surgery as much as adult children.

An adult child who visits intermittently might notice vision changes in an older parent that others don't.

Cataract is one of the most common treatable causes of vision impairment in the United States. Cataract surgery can improve quality of life, reduce risk of falls and cut cognitive decline among older adults.

Mindfulness meditation reduces incidence of major depression Treating

American Academy of Family Physicians

Among primary care patients with subthreshold depression, mindfulness meditation training reduces the incidence of major depression and improves depression symptoms. A randomized controlled trial of adults with subthreshold depression compared a usual care group in which there was no psychological intervention (n=116) with a behavioral activation group focused on mindfulness training (n=115). Intervention participants were invited to attend weekly two-hour mindfulness training sessions for eight consecutive weeks.

At 12 months, there was a statistically significant difference in the incidence of major depressive disorder between groups (11 percent in the mindfulness group compared to 27 percent in usual care).

 Mindfulness training also had a small effect in reducing depression symptoms (between-group mean difference = 3.85). Other secondary outcomes demonstrated no significant change. The authors suggest that, for patients with subthreshold depression who have not had a major depressive episode in the past six months, mindfulness training is a feasible method of preventing major depression. The authors plan future research into the cost-effectiveness, health service use implications, and acceptability of mindfulness training.

Thursday, March 8, 2018

A lifetime of regular exercise slows down aging

Researchers at the University of Birmingham and King's College London have found that staying active keeps the body young and healthy.

The researchers set out to assess the health of older adults who had exercised most of their adult lives to see if this could slow down ageing.

The study recruited 125 amateur cyclists aged 55 to 79, 84 of which were male and 41 were female.

The men had to be able to cycle 100 km in under 6.5 hours, while the women had to be able to cycle 60 km in 5.5 hours. Smokers, heavy drinkers and those with high blood pressure or other health conditions were excluded from the study.

The participants underwent a series of tests in the laboratory and were compared to a group of adults who do not partake in regular physical activity. This group consisted of 75 healthy people aged 57 to 80 and 55 healthy young adults aged 20 to 36.

The study showed that loss of muscle mass and strength did not occur in those who exercise regularly. The cyclists also did not increase their body fat or cholesterol levels with age and the men's testosterone levels also remained high, suggesting that they may have avoided most of the male menopause.

More surprisingly, the study also revealed that the benefits of exercise extend beyond muscle as the cyclists also had an immune system that did not seem to have aged either.

An organ called the thymus, which makes immune cells called T cells, starts to shrink from the age of 20 and makes less T cells. In this study, however, the cyclists' thymuses were making as many T cells as those of a young person.

The findings come as figures show that less than half of over 65s do enough exercise to stay healthy and more than half of those aged over 65 suffer from at least two diseases.* Professor Janet Lord, Director of the Institute of Inflammation and Ageing at the University of Birmingham, said:

"Hippocrates in 400 BC said that exercise is man's best medicine, but his message has been lost over time and we are an increasingly sedentary society. 
"However, importantly, our findings debunk the assumption that ageing automatically makes us more frail.
"Our research means we now have strong evidence that encouraging people to commit to regular exercise throughout their lives is a viable solution to the problem that we are living longer but not healthier."
Dr Niharika Arora Duggal, also of the University of Birmingham, said:
"We hope these findings prevent the danger that, as a society, we accept that old age and disease are normal bedfellows and that the third age of man is something to be endured and not enjoyed."
Professor Stephen Harridge, Director of the Centre of Human & Aerospace Physiological Sciences at King's College London, said:
"The findings emphasise the fact that the cyclists do not exercise because they are healthy, but that they are healthy because they have been exercising for such a large proportion of their lives.
"Their bodies have been allowed to age optimally, free from the problems usually caused by inactivity. Remove the activity and their health would likely deteriorate."
Norman Lazarus, Emeritus Professor at King's College London and also a master cyclist and Dr Ross Pollock, who undertook the muscle study, both agreed that:
"Most of us who exercise have nowhere near the physiological capacities of elite athletes.
"We exercise mainly to enjoy ourselves. Nearly everybody can partake in an exercise that is in keeping with their own physiological capabilities.
"Find an exercise that you enjoy in whatever environment that suits you and make a habit of physical activity. You will reap the rewards in later life by enjoying an independent and productive old age."
The research findings are detailed in two papers published today in Aging Cell and are the result of an ongoing joint study by the two universities, funded by the BUPA foundation.

The researchers hope to continue to assess the cyclists to see if they continue to cycle and stay young.

Wednesday, March 7, 2018

Why the latest shingles vaccine is more than 90 percent effective

A new study has shown how the body's immune system responds to the new shingles vaccine, Shingrix, making it more than 90% effective at protecting against the virus.

The trial included more than 15,000 participants across 18 countries in Europe, North America, Latin America, Asia and Australia. Participants in the trial received two doses of the vaccine, with the doses given two months apart.

Lead researcher Professor Tony Cunningham from the Westmead Institute for Medical Research said the study shows that the vaccine stimulates production of a specific immune memory cell (CD4 T cells), generating a strong and sustained protection against the virus.

"The body has two types of immunity: protein antibodies and white blood cells known as T cells. As the virus circulates around the body, antibodies block it from entering cells. But when the virus does get into cells your T cells try to kill those infected cells.

"Our research shows that the vaccine stimulates your immune system to produce more antibodies and it generates a 24-fold increase in T cells. This is 12 times higher than other less effective shingles vaccines.

The research, published in the Journal of Infectious Diseases, shows that Shingrix offers protection for up to four years, but Professor Cunningham believes it will last much longer.

"The second dose of the vaccine is important to ensure long-term protection," Professor Cunningham said.

"The efficacy is approximately 90% for all age groups--even for those over 70 years of age.
"This is quite remarkable because there are no other vaccines that perform nearly so well for people in their 70s and their 80s. We are seeing results comparable to those of childhood vaccinations.

"What's particularly exciting, though, is that 90% of recipients had an increased immune response sustained across the 3-year duration of the study.

"We anticipate that this protection will actually last much, much longer. We are now measuring the efficacy of the vaccine over the next 10 years and are very optimistic about the results," he said.
Shingrix is different from most other vaccines. Many vaccines are made from a weakened form of the virus, but Shingrix is made from just a single protein--known as glycoprotein E--that comes from the outer shell of the herpes zoster virus.

The vaccine also contains an adjuvant--a substance that helps your body fight off the virus. It is the first shingles vaccine to combine a non-live antigen with a specifically designed adjuvant.
Shingles is a viral infection, caused by the herpes zoster virus--the same virus that causes chickenpox.

The incidence of shingles increases as we get older, because the body's natural immunity declines.
"When people reach their 50s and 60s, T cell immunity declines allowing shingles to strike. That's why our adult vaccine is directed specifically at T cell immunity," Professor Cunningham said.

Most adults have been infected with the herpes zoster virus and are at risk of shingles, even if they do not remember having chicken pox. By age 85, approximately 50% of the population will develop shingles. Vaccination is the only way to protect against shingles.