Friday, October 13, 2017

Learning and staying in shape key to longer lifespan


People who are overweight cut their life expectancy by two months for every extra kilogramme of weight they carry, research suggests.

A major study of the genes that underpin longevity has also found that education leads to a longer life, with almost a year added for each year spent studying beyond school.

Other key findings are that people who give up smoking, study for longer and are open to new experiences might expect to live longer.

Scientists at the University of Edinburgh analysed genetic information from more than 600,000 people alongside records of their parents' lifespan.

Because people share half of their genetic information with each of their parents, the team were able to calculate the impact of various genes on life expectancy.

Lifestyle choices are influenced to a certain extent by our DNA - genes, for example, have been linked to increased alcohol consumption and addiction. The researchers were therefore able to work out which have the greatest influence on lifespan.

Their method was designed to rule out the chances that any observed associations could be caused by a separate, linked factor. This enabled them to pinpoint exactly which lifestyle factors cause people to live longer, or shorter, lives.

They found that cigarette smoking and traits associated with lung cancer had the greatest impact on shortening lifespan.

For example, smoking a packet of cigarettes per day over a lifetime knocks an average of seven years off life expectancy, they calculated. But smokers who give up can eventually expect to live as long as somebody who has never smoked.

Body fat and other factors linked to diabetes also have a negative influence on life expectancy.
The study also identified two new DNA differences that affect lifespan. The first - in a gene that affects blood cholesterol levels - reduces lifespan by around eight months. The second - in a gene linked to the immune system - adds around half a year to life expectancy.

The research, published in Nature Communications, was funded by the Medical Research Council.
Data was drawn from 25 separate population studies from Europe, Australia and North America, including the UK Biobank - a major study into the role of genetics and lifestyle in health and disease.
Professor Jim Wilson, of the University of Edinburgh's Usher Institute, said: "The power of big data and genetics allow us to compare the effect of different behaviours and diseases in terms of months and years of life lost or gained, and to distinguish between mere association and causal effect."

Dr Peter Joshi, Chancellor's Fellow at the University of Edinburgh's Usher Institute, said: "Our study has estimated the causal effect of lifestyle choices. We found that, on average, smoking a pack a day reduces lifespan by seven years, whilst losing one kilogram of weight will increase your lifespan by two months."

Wednesday, October 11, 2017

Experts call for more rigor, less hype, for mindfulness and meditation


 Dependable scientific evidence has lagged worrisomely behind the rapid and widespread adoption of mindfulness and meditation for pursuing an array of mental and physical wellness goals, wrote a group of 15 experts in a new article in Perspectives on Psychological Science. The article offers a "critical evaluation and prescriptive agenda" to help the burgeoning mindfulness industry replace ambiguous hype with rigor in its research and clinical implementations.
Recent years have seen a huge surge not only in media and scientific articles about mindfulness and meditation, the authors wrote, but also in the implementation of medical interventions for everything from depression to addiction, pain and stress. The widespread adoption of therapies has put the field at a critical crossroads, the authors argued, where appropriate checks and balances must be implemented.

"Misinformation and poor methodology associated with past studies of mindfulness may lead public consumers to be harmed, misled and disappointed," they wrote.

Co-author Willoughby Britton, an assistant professor of psychiatry and behavior at the Warren Alpert Medical School of Brown University said: "We are sometimes overselling the benefits of mindfulness to pretty much any person who has any condition, without much caution, nuance or condition-specific modifications, instructor training criteria, and basic science around mechanism of action. The possibility of unsafe or adverse effects has been largely ignored. This situation is not unique to mindfulness, but because of mindfulness's widespread use in mental health, schools and apps, it is not ideal from a public health perspective."

Lead author Nicholas Van Dam, a clinical psychologist and research fellow in psychological sciences at the University of Melbourne in Australia, said that the point of the article is not to disparage mindfulness and meditation practice or research, but to ensure that their applications for enhancing mental and physical health become more reflective of scientific evidence. So far, such applications have largely been unsupported, according to major reviews of available evidence in 2007 and again in 2014.

"The authors think there can be something beneficial about mindfulness and meditation," Van Dam said. "We think these practices might help people. But the rigor that should go along with developing and applying them just isn't there yet. Results from the few large-scale studies that have been conducted so far have proven equivocal at best."

Added co-author David E. Meyer, a professor of psychology at the University of Michigan, "Sometimes, truly promising fields of endeavor get outstripped by efforts to harvest them before they're really ripe; then workers there must step back, pause to take stock, and get a better plan before moving onward."

Future efforts to improve the quality of mindfulness and meditation research will be bolstered by a new research center at Brown University, led by Eric Loucks, an associate professor in the university's School of Public Health.

"The center's mission will be to perform high-quality, methodologically rigorous research about impacts of mindfulness on health, and to offer collaborative, evidence-based resources for hospitals, schools and businesses that are interested in offering mindfulness-based interventions," Loucks said.

A young, undefined field
Among the biggest problems facing the field is that mindfulness is poorly and inconsistently defined both in popular media and the scientific literature. According to the authors, there "is neither one universally accepted technical definition of 'mindfulness' nor any broad agreement about detailed aspects of the underlying concept to which it refers." As a result, research papers have varied widely in what they actually examine, and often, their focus can be hard to discern.

"Any study that uses the term 'mindfulness' must be scrutinized carefully, ascertaining exactly what type of 'mindfulness' was involved, what sorts of explicit instruction were actually given to participants for directing practice," the authors wrote. "When formal meditation was used in a study, one ought to consider whether a specifically defined type of mindfulness or other meditation was the target practice."

"Without specific, well-defined terms to describe not only practices but also their effects, studies of interventions such as mindfulness-based stress reduction (MBSR) cannot provide valid and comparable measurements to produce reliable evidence." As part of its proposed remedy, the new article offers a "non-exhaustive list of defining features for characterizing contemplative and medication practices.
"
Greater rigor
Along with specific, precise and standardized definitions, similar improvements in research methodology must also come, the authors wrote.

"Many intervention studies lack or have inactive control groups," Van Dam said.

The field also has struggled to achieve consistency in what it is being measured and how to measure those things perceived to be of greatest importance to mindfulness.

Van Dam said the situation is akin to earlier psychological research on intelligence. This concept proved to be too broad and too vague to measure directly. Ultimately, however, psychologists have made progress by studying the "particular cognitive capacities that, in combination, may make people functionally more or less intelligent," he and his co-authors wrote.

Thus, the authors wrote, "We recommend that future research on mindfulness aim to produce a body of work for describing and explaining what biological, emotional, cognitive, behavioral and social, as well as other such mental and physical functions, change with mindfulness training."

Clinical care
A wide variety of contemplative practices have been studied for an even larger variety of purposes, yet in both basic and clinical studies of mindfulness and meditation, researchers have rarely advanced to the stage where they can confidently conclude whether particular effects or specific benefits resulted directly from the practice. Measured by the National Institutes of Health's stage model for clinical research, only 30 percent of mindfulness-based interventions (MBIs) have moved past the first stage, and only 9 percent have tested efficacy in a research clinic against an active control.
"Given the absence of scientific rigor in much clinical mindfulness research, evidence for use of MBIs in clinical contexts should be considered preliminary.," the authors wrote.

The proposed agenda for future research is rigorous and extensive, Van Dam said.

"Replication of earlier studies with appropriately randomized designs and proper active control groups will be absolutely critical," the authors continued. "In conducting this work, we recommend that researchers provide explicit detail of mindfulness measures, primary outcome measures, mindfulness/meditation practices and intervention protocol."

Researchers and care providers involved with delivering MBIs have begun to become more vigilant about possible adverse effects, the authors wrote, but more needs to be done. As of 2015, fewer than 25 percent of meditation trials actively monitored for negative or challenging experiences.

Contemplating contemplative neuroscience
Van Dam said recent efforts to assess the neural correlates of mindfulness and meditation with technologies, such as magnetic resonance imaging (MRI) and magnetoencephalography, may perhaps have the potential to bring new rigor to the field. Nonetheless, he and his co-authors also express concern in the article that these technologies so far have not fulfilled this potential.

The authors note that technologies such as MRI depend on subjects remaining physically still while being tested, and image quality can be affected by subjects' rate of breathing. Experienced meditators may be better suited to maintaining ideal physiological states for MRI studies than are inexperienced individuals or non-meditators. Due to such problematic factors, between-group differences in brain scans might have little to do with the mental state researchers are attempting to measure and much to do with head motion and/or breathing differences.

"Contemplative neuroscience has often led to overly simplistic interpretations of nuanced neurocognitive and affective phenomena," the authors wrote. "As a result of such oversimplifications, meditative benefits may be exaggerated and undue societal urgency to undertake mindfulness practices may be encouraged."

Ultimately that's the authors' shared concern: Insufficient research may mislead people to think that the vague brands of "mindfulness" and "meditation" are broad-based panaceas when in fact refined interventions may only be helpful for particular people in specific circumstances. More, and much better, scientific studies are needed to clarify these matters. Otherwise people may waste time and money, or worse, suffer needless adverse effects.

"This paper is a coordinated effort among concerned mindfulness researchers and meditation scholars to rectify this gap to maximize benefit and minimize harm from MBIs," Britton said.

Older adults with insomnia may fall even more when on prescription sleep meds



Taking physician-recommended sleep medications to treat insomnia may actually increase the risk of falling for older adults, according to a team of sleep researchers.

The problem may stem from older people continuing to take sleep medications long after they should, said Orfeu Buxton, associate professor of biobehavioral health, Penn State.

"The importance for me -- personally and professionally -- is that this matches what I've heard from gerontologists and physicians treating older patients at assisted-living and nursing homes," said Buxton. "So many older adults come into the care of a physician late in life with a huge medication burden. They've been taking sleeping medications for years, or decades, and it's the physician's problem to get them off of medications that are no longer appropriate at that age."

The medications, which include sleeping pills -- some of which are sedative hypnotics -- often have side effects that cause problems with balance, memory and situational awareness, according to Buxton and his colleagues, Soomi Lee, assistant research professor in biobehavioral health, Penn State, and Tuo-Yu Chen, visiting assistant professor, Duke-NUS Graduate Medical School and an international faculty affiliate at Penn State Center for Healthy Aging, who report their findings in the current issue of Sleep.

The more likely a person has difficulty sleeping, the more likely they are going to be up and walking around in the dark at night," said Buxton. "You might think that if they have a physician-prescribed sleep medication that risk of falling might go down because they would stay in bed, but it doesn't. It worsens."

Falls are a major health concern for older adults and a costly strain on the American health system, according to the researchers. More than 30 percent of adults aged 60 who live on their own -- community dwelling -- fall each year. The costs for falls in the older adult population is estimated at $23.3 billion.

Buxton suggests that non-drug-related approaches to treating sleep disorders may be more effective for older adults and not put them at risk for increased falls.

"If you have difficulty sleeping the most effective treatment is cognitive behavioral therapy for insomnia -- CBTi -- which teaches patients how to learn to sleep well again," said Buxton. "In contrast, medications have many unintended consequences that worsen with later age and with the duration of taking them. Almost all the sleeping medications are meant only for short-term use and even the long-term use indications are supposed to be on the order of weeks, not decades."

The researchers also found a link between the number of insomnia symptoms and fall risk. The four symptoms of insomnia -- trouble falling asleep, waking up during the night, waking up too early and not feeling rested -- all increased the risks of falls for older adults, according to the researchers.

The probability of a fall goes steadily upward from 28 percent for older adults with no symptoms of insomnia, to 40 percent for older adults reporting four different symptoms of insomnia, according to the researchers. However, the risk of falls for those taking physician-prescribed insomnia medicine was always higher for older adults with insomnia, even those who had all four symptoms of insomnia. Buxton said that future research should be aimed at studying ways to improve the sleep of older adults without sleeping pills.

"We have an urgent need to get older adults with insomnia off of hypnotic medications, they are often contraindicated in older adults," said Buxton. "We think the most important next studies to do are how to manage that titration process with cognitive behavioral therapy to assist older adults sleeping well without the side effects of hypnotic drugs."

The researchers used data from the Health and Retirement Study, a longitudinal study featuring a representative sample of 6,882 Americans from the National Institute on Aging.

"The HRS data is publicly available data set and the data collected was about older adults' lifestyles and their health status, so these older adults were well-functioning, community-dwelling older adults aged 65 and older in the U.S.," said Lee. "I think it's fair to say that it's nationally representative of this group. Also, this is one of the first studies that reveal the longitudinal associations of insomnia burden and sleep medications with falls."

Despite effectiveness women remain skeptical of hormones at menopause -- what's the problem?


Women today have more options than ever before for treating their menopause symptoms, although hormone therapy still ranks as the most effective treatment for debilitating symptoms such as hot flashes. A new study demonstrates, however, that women remain skeptical regarding the safety of hormone therapy and prefer less proven options. The study results will be presented during The North American Menopause Society (NAMS) Annual Meeting in Philadelphia, October 11-14.

Hot flashes (including night sweats) occur in up to 75% to 80% of all women in the US with some of them considered debilitating and lasting for many years after the end of menstrual cycles. Despite the fact that hormone therapy has proven to be the most effective treatment for hot flashes and other bothersome menopause symptoms, women and their healthcare providers still question their safety which has led to a decreased number of prescriptions and usage of hormones. This was one of the first studies to examine women's beliefs and attitudes toward menopause in general and hormone therapy specifically.

Among the many findings, the survey results showed that participants were significantly less willing to use hormones for hot flashes and instead used exercise, diet, herbal supplements, acupuncture, or meditation. This was despite the fact that participants strongly agreed that hormone therapy could effectively reduce hot flashes.

"Our findings suggest that women are less willing to use the most empirically validated treatment for hot flashes than other alternative treatment options," says Dr. Terry Gibbs, lead author of the study from Promedica Physicians in Sylvania, Ohio. "Also, their confidence in successful treatment outcomes was not greater for hormone therapy than the other options."

"This study tells us that there remains an unmet need to educate women about the safety and effectiveness of hormone therapy for most symptomatic women. The benefits go beyond the relief of hot flashes and include improvement in night sweats, sleep disruption, prevention of bone loss, and fewer heart events," says Dr. JoAnn Pinkerton, NAMS executive director.

Confusion about long-term treatment of osteoporosis clarified


Osteoporosis is a common disorder among postmenopausal women which results in an increased risk of fractures. While several therapies improve bone strength and reduce the risk of spine and hip fracture, there is no cure for osteoporosis, and long-term treatment is needed. An upcoming presentation at The North American Menopause Society (NAMS) Annual Meeting in Philadelphia October 11-14 is scheduled to present new evidence about the long-term effectiveness and safety of treatment with bisphosphonates and denosumab.

Bisphosphonates and denosumab are the most commonly prescribed treatments for osteoporosis. Protection from fractures occurs within the first few months of treatment and persists as long as treatment is continued. Upon stopping bisphosphonate therapy, protection from fractures is gradually lost over three to five years. Treatment for more than three years has been associated with an increasing risk of unusual or "atypical" fractures of the femur (thigh bone). After five years of treatment, the risk of these atypical fractures is about 20 per 100,000 patients and increases to about 1/1,000 patients after eight to ten years of treatment.

The combination of increased risk of atypical fracture along with a relatively slow offset of the protection from fractures due to osteoporosis led to the confusing concept of a "bisphosphonate holiday."

 The American Society for Bone and Mineral Research has recently provided clear recommendations about "bisphosphonate holidays." After three to five years of bisphosphonate treatment, a patient's risk of fracture should be reevaluated. For patients remaining at high risk of fracture (those with previous hip, spine, or multiple other fractures or with bone density values remaining in the osteoporosis range), continuing treatment or changing to a different drug like denosumab is important. For patients whose risk of fracture is lower, stopping treatment for two to three years (the "holiday") can be considered but is not mandatory.

It's important to note that the concept of a "holiday" from therapy applies only to the bisphosphonates and not to any of the other drugs used to treat osteoporosis. The beneficial effects of these other medicines, including raloxifene, teriparatide, and denosumab, are lost quickly when treatment is stopped.

"Because protection from fractures disappears quickly if denosumab treatment is stopped, and since there are no currently known safety issues that limit the duration of denosumab therapy, there is no justification for a drug holiday with this treatment," says Dr. Michael McClung of the Oregon Osteoporosis Center in Portland, Oregon, who will be presenting his recommendations on long-term osteoporosis therapy at the NAMS Annual Meeting. "Just as we do not recommend stopping treatment for high blood pressure or diabetes, it is necessary to have a long-term treatment plan for postmenopausal women with osteoporosis if the benefits of our therapies are to be realized."

"Prevention of osteoporosis should be a goal for those treating menopausal women, as up to 20% of bone loss occurs within the first five years of menopause. Once diagnosed with osteoporosis, the goal becomes lowering the risk of fractures as fractures can be life changing or life limiting. This presentation will offer valuable insights about the need for long-term treatment and will change the way health care providers approach long-term osteoporosis management," says Dr. JoAnn Pinkerton, NAMS executive director.

Aging slows perception of falls



Seniors need twice as long as young adults to realize they are falling, a delay that puts them at increased risk for serious injury, according to a new study from the University of Waterloo.

The findings will help shape the development of wearable fall prevention technology and allow clinicians to more accurately identify at-risk individuals. Falls are the leading cause of death and hospitalization.

"Falling threatens one's survival," said Michael Barnett-Cowan, a kinesiology professor at Waterloo and senior author on the study. "When the nervous system's ability to detect a fall and compensate with protective reflexes diminishes, the risk of injury or death increases significantly.

"Age and associated delays will need to be seriously considered when designing any aids to help seniors mitigate this risk."

According to the Public Health Agency of Canada between 20 and 30 per cent of seniors fall each year. Seniors also make up the fastest growing segment of the global population. By 2040, more than one billion people will be over the age of 65.

"Measuring fall perception not only is important in prevention efforts, but also provides information about how the brain processes sensory information and how this changes with age," said Julian Lupo, a graduate student and the study's lead author.

To measure fall perception, researchers presented study participants with a sound at different times relative to a supervised fall. They found that young adults required the fall to happen about 44 milliseconds before the sound in order for both cues to be perceived as occurring simultaneously. But adults over 60 years old required fall onset to occur about 88 milliseconds before the sound.

"This lag means that by the time older adults realize they are falling, it's often too late for for them to consciously do anything about it," said Barnett Cowan. "Given that falls are often the catalyst for a transition to long-term care, these findings highlight both the importance of adequate assessement for older adults and the need to expediete new prevention technology."

Falls are a leading cause of overall injury costs in Canada, with a total economic burden of falls estimated to be $6 billion annually. Seniors who are hospitalized for a fall remain in hospital an average of nine days longer than those hospitalized for any other cause.

The study appears in the journal Gait & Posture.

Ketone nutritional supplements: Good or bad for athletic performance?


In the quest to improve physical performance, many athletes are turning to untested nutritional supplements. But in the case of one recently available and popular class of supplements--ketone salts--research suggests it may inhibit, rather than improve, athletic performance during high-intensity exercise.

"Ketone salts are relatively new to the market and there's not much research on their impact on performance," says the study's co-author Jonathan Little, assistant professor in UBC Okanagan's School of Health and Exercise Sciences. "We know from one previously published study that ketone supplements may improve long-duration endurance performance but we're interested what happens during short-duration and high-intensity workouts, like running a 10k or cycling up a hill."

"It turns out that ketone salt supplements actually impair high-intensity exercise performance."
Ketone salts work by artificially elevating blood ketone levels, similar to what happens naturally during periods of starvation, and forces the body to rely on burning fat as a fuel, explains Little. Burning fat is a more effective long-term fuel but is more complex to process and isn't as readily accessible for quick bursts of muscle activity as is a fuel like glucose.

"Elevated blood ketones seem to inhibit the body's use of glycogen, the stored form of glucose, and favours burning fat instead," adds Little. "That means that the body's quick-burning fuel cannot be accessed during high-intensity bursts of activity and athletic performance is dropping off as a result."

In his study, Little recruited ten healthy adult males with similar athletic abilities and body mass indices. After a period of fasting, they were asked to consume either beta-hydroxybutyrate ketone salts or a flavour-matched placebo, in a randomized order, and then engage in a cycling time trial. Power output on the day participants consumed ketone salts was seven per cent lower than on the day when they consumed the placebo.

"Often these supplements are marketed as a means of improving athletic performance but in this case, the research tells a very different story," says Little. "On top of that, the long-term impacts of artificially increasing blood ketone levels--essentially tricking the body into thinking it is in a state of starvation--is completely unknown."

"I hope this helps athletes navigate the science of supplements rather than relying on label marketing alone."