News Briefs – Strategy for Disease Prevention; Many Alzheimer’s Cases Are Preventable; Good Habits Reduce Heart RisksMichael Downey September 1, 2014
STUDY PLEADS FOR NEW STRATEGY FOR DISEASE PREVENTION
Researchers have concluded that, by treating the overall metabolic and molecular causes of human aging, it may be possible to help people stay healthy into their 70s and 80s. Medicine, the report found, focuses almost entirely on fighting chronic diseases in a piecemeal fashion as symptoms develop. Instead, more efforts should be directed to promoting broader interventions that have the potential to prevent multiple chronic diseases and extend healthy life spans.
The scientists call for moving forward with preclinical and clinical strategies in humans that have been shown to delay aging in animals. In addition to healthy diet and regular exercise, these strategies include slowing the metabolic and molecular aging pathways, such as the incremental accumulation of cellular damage that occurs over time. The study suggested that economic incentives in biomedical research and healthcare currently reward treating disease more than promoting good health. The diseases of old age, such as heart failure, diabetes, arthritis, cancer, and Alzheimer’s disease, tend to come as a package, the researchers write. (More than 70% of people over 65 have two or more chronic diseases. Studies of diet, genes, and drugs indicate that interventions targeted to specific molecular pathways that delay one age-related disease often stave off others, too.)
For example, calorie restriction combined with optimal nutrition is known to help animals live up to 50% longer while preventing an array of age-related diseases right up until eventual death.
The study reports that most clinical doctors do not realize how much already is understood about the molecular mechanisms of aging and their link to chronic diseases, and generally do not understand precisely how aging pathways work. The study suggests that public money be invested in extending healthy lifespan, not by fighting individual diseases, but by slowing aging. Otherwise, we will founder in a demographic crisis of increased disability and escalating health care costs.
This report was published in the July 24, 2014 issue of the journal Nature. It can now be read in full at https://tinyurl.com/nerjlp9
ONE THIRD OF ALZHEIMER’S CASES ARE PREVENTABLE
A study has found that one in three cases of Alzheimer’s could be prevented by modifying risk factors to which the memory-robbing disease can be attributed. (Current estimates suggest that by 2050, more than 106 million people will be living with this disease, a huge increase on the 30 million people affected by the disease in 2010. Alzheimer’s is caused by an interplay of genetic and lifestyle factors.) There are seven key risk factors for which there is consistent evidence of an association with this disease.
Risk Factors for Developing Alzheimer’s
- midlife high blood pressure
- midlife obesity
- physical inactivity
- low educational attainment
The researchers calculated that by reducing the relative risk from each of these risk factors by 10%, it would be possible to reduce the prevalence of Alzheimer’s in 2050 by 8.5%, preventing 9 million cases. Changing some risk factors can improve other risks; for example, boosting physical activity can also help reduce obesity, diabetes, and high blood pressure. This research is published in the August, 2014 edition of The Lancet Neurology. This research is published in the August, 2014 edition of The Lancet Neurology. The study is now accessible online at https://tinyurl.com/mr86ptl for a fee.
STARTING GOOD HEART HABITS IN 30s, 40s STILL SLASHES HEART RISK
Scientists have reported that when adults in their 30s and 40s decide to drop unhealthy habits that are harmful to their heart and embrace heart-healthy lifestyle changes, they can control and potentially even reverse the natural progression of coronary artery disease.
On the flip side, they also found that if people drop healthy habits or pick up more bad habits as they age, there is a measurable, detrimental impact on their coronary arteries.
The researchers examined healthy lifestyle behaviours and coronary artery calcification and thickening among the more than 5,000 participants in the study who were assessed at baseline, when participants were aged 18 to 30, and again 20 years later. The healthy lifestyle factors assessed were: not being overweight or obese, being a nonsmoker, being physically active, and having low alcohol intake and a healthy diet. By young adulthood, at the beginning of the study, less than 10% of the participants reported all five healthy lifestyle behaviours. At the 20-year mark, about 25% of the subjects had added at least one healthy lifestyle behaviour. Each increase of just one healthy lifestyle factor was associated with reduced odds of detectable coronary artery calcification and with lower intima-media thickness; these are two major markers of cardiovascular disease that can predict future cardiovascular events. (This finding is important because it helps to debunk two myths held by some doctors: that it is nearly impossible to change patient behaviour; and that adulthood is too late for healthy lifestyle changes to reduce the risk of coronary artery disease.)
This study was published July 1, 2014 in the journal Circulation. The full-text report can now be accessed online at https://tinyurl.com/oqceje5 with a fee.
ZINC REVIEW CLARIFIES ITS CRITICAL BODY EFFECTS
A systematic review of previous studies has concluded that the mineral zinc is one of the most important essential trace metals in human nutrition and lifestyle. The evidence suggested that zinc is not only a vital element in various physiological processes, but is also a drug in the prevention of many diseases. (The adult body contains about two to three grams of zinc, found in organs, tissues, bones, fluids, and cells.)
The review included numerous studies that showed a relationship between zinc and vital human physiological processes, including the brain, cardiovascular system, liver, pregnancy health, insulin production, endocrine function, wound healing, and pneumonia.
For example, zinc levels were found to be lower among Alzheimer’s and Parkinson’s patients. Zinc plays a role in blood pressure regulation. Zinc deficiency was found in those with cirrhosis, and alcoholic and nonalcoholic liver disease. Deficiency during pregnancy can increase maternal morbidity, inefficient labour, and risk to fetus. Zinc plays a role in insulin synthesis, storage, and secretion; and is involved in diabetes-related coronary artery disease.
In geriatric patients, zinc deficiency correlates with lower thymus activity, decreased vaccination response, and reduced immunity. Low zinc intake is linked to slower wound healing and appears crucial to gastric ulcer healing. And zinc may shorten duration of severe pneumonia and time in the hospital. However, excess zinc promotes obesity, anemia, copper deficiency, and other problems. The Recommended Daily Intake is 8 mg for women and 11 mg for men, although research shows most people exceed these intakes.
This study was first released on July 21, 2014, ahead of publication in a later issue of the journal Comprehensive Reviews in Food Science and Food Safety. Read the entire report athttps://tinyurl.com/q8b5ns5 free of charge.
INADEQUATE GUT BACTERIA LINKED TO TYPE 2 DIABETES, OBESITY
A study has found that people with Type 2 diabetes or obesity have significant differences in the composition of their intestinal microorganisms, or gut bacteria, compared to healthy people. (Other recent reports have found an association between specific bacterial species in the human digestive system and obesity and diabetes. The human digestive system contains an estimated 10 trillion to 100 trillion bacteria and other microscopic organisms, with each person housing at least 160 different species of organisms.)
This study included 27 severely obese adults with a body mass index or BMI exceeding 35, as well as 26 adults with newly diagnosed Type 2 diabetes, and 28 healthy control subjects. No participants had taken antibiotics within the past three months, and none was currently taking medications. Fecal analysis using a molecular biology technique showed that several of the most common types of gut bacteria, including Firmicutes, Bifidobacteria, and Clostridium leptum, were present at considerably lower levels in the obese and diabetic groups, compared with healthy controls. These types of bacteria were 4.2 to 12.5% lower in the obese patients and 10 to 11.5% lower in the diabetic patients. Further studies are needed to help determine whether these gut microbial changes are a cause or an effect of diabetes and obesity. Manipulation of intestinal bacteria could offer a new approach to managing obesity and Type 2 diabetes.
The researchers presented these results in Chicago on June 22, 2014 at the joint meeting of the International Society of Endocrinology and the Endocrine Society. The study details will be published at a later date.
SOME PAIN DRUGS LINKED TO STROKE, HEART ATTACK RISK IN WOMEN
New research has found that the regular use of some non-steroidal anti-inflammatory drugs, or NSAIDs, increases cardiovascular risk in postmenopausal women. The researchers found that regular use of naproxen, the active ingredient in over-the-counter pain medications such as Aleve, is associated with a 10% increased risk of heart attack, stroke and death in women who are postmenopausal. Regular use was defined as at least twice per week for the previous two weeks. The link remained even after the scientists controlled for potentially confounding factors such as obesity, hypertension, diabetes, use of aspirin, and other health factors. The study was observational in nature and reveals only an association between pain drug use and cardiovascular impacts, but not necessarily a cause-and-effect relationship.
This was the first study of its size to examine the effects of regular NSAID use on women. (NSAIDs include over-the-counter medications such as ibuprofen, branded as Motrin, as well as prescription drugs such as celecoxib, branded as Celebrex.) This study also confirmed that regular use of any NSAID is associated with harm, such as digestive bleeding. Although this study found, for the first time, an increased cardiovascular risk with regular naproxen use, it found no cardiovascular or stroke harm associated with ibuprofen or Motrin. This study was just released online by Circulation: Cardiovascular Quality and Outcomes, ahead of publication in a later issue of the journal. The full study can be read at https://tinyurl.com/pvm7zpz for a fee.
MIDLIFE STIMULATION LOWERS RISK OF LATE-LIFE DEMENTIA
A study has confirmed that a lifetime of intellectual stimulation in the form of education and career can reduce the risk of dementia in later life; and has discovered that, for those with little early-life education and professional stimulation, pursuing mentally stimulating activities beginning in midlife can still have a very substantial effect on dementia risk reduction. This was surprising considering the shorter overall period of time spent in intellectual pursuits by those beginning such activities only in mid-life.
Adopting a mentally stimulating lifestyle in midlife includes such activities as reading, playing music and games, involvement in artwork and crafts, and other brain activating pursuits. This is very encouraging news, because it proves that even those who did not acquire a lot of education or get exposure to intellectual stimulation during their career, can benefit greatly from intellectual leisure activity in midlife.
The team tracked nearly 2,000 men and women aged 70 to 89 and assessed their level of cognitive (thinking and memory) impairment. All participants were subsequently scored on their level of past educational achievements, while occupational histories were ranked by degree of intellectual complexity. Participants completed questionnaires designed to pinpoint how much they engaged in intellectually demanding activities during the prior 12 months and during middle age, defined as from age 50 to 65.
Also, all were examined to see if they carried a specific variant of the APOE gene, considered the most significant genetic risk factor for late-onset Alzheimer’s. Subjects showing decreased dementia risk included those with a lifetime history of stimulation, who showed the greatest benefits; those with only midlife stimulation, who showed a significant three-year delay in dementia onset; and even those with the APOE4 gene, who saw their risk of dementia risk delayed by nearly nine years compared to APOE4 carriers with the lowest intellectual stimulation.
This research was released early online at the site of JAMA Neurology on June 23, 2014 but will not be published in the journal until a later time. Meanwhile, the full study can now be downloaded at https://tinyurl.com/oy9syjw with subscription or access fee.
HIGH BLOOD PRESSURE LINKED TO LOW VITAMIN D LEVELS
New genetic research provides compelling evidence that low levels of vitamin D play a role in causing the development of high blood pressure, or hypertension, and that vitamin D supplementation could be effective in combating some cases of hypertension at low cost relative to expensive antihypertensive drugs. (Results from observational studies have suggested a strong association between low vitamin D levels and increases in blood pressure and hypertension, but until now, a direct cause-and-effect link has not been shown.)
Researchers found that for each 10% increase in vitamin D concentration, there was an 8.1% decrease in the odds of developing hypertension.
The study utilized a technique known as Mendelian randomization, which involves using genetic data from a large number of people to determine cause and effect and helps to better avoid skewing data due to confounding, reverse causation, and bias. Because the possibility still exists that these findings were caused by chance, the researchers stressed that the results need to be replicated in another similar study.
These findings were released June 26, 2014 and will be published later in an upcoming issue of the journal The Lancet Diabetes and Endocrinology. The full-text version of this study can now be read online at https://tinyurl.com/pl8zgsu without charge.
DID YOU KNOW…?
Consumption of fish oil supplements results in reduced cognitive decline in older adults who do not already have dementia, according to a June 2014 study in the journal Alzheimer’s and Dementia.
LESS SLEEP CAUSES FASTER BRAIN AGING
Researchers have found evidence that the less sleep older adults manage to get, the faster their brains age. (Past research has examined the impact of sleep duration on cognitive function in older adults, but the effects of sleep duration on the speed of development of neurodegenerative diseases such as Alzheimer’s have never before been measured.) These findings, relevant in this rapidly aging society, pave the way for future work on sleep loss and its contribution to cognitive decline, including dementia.
The study examined the data of 66 older adults. Participants underwent structural MRI brain scans that measured brain volume. They also received neuropsychological assessments that tested cognitive function every two years. Additionally, their sleep duration was recorded through a questionnaire. Those who slept fewer hours showed evidence of faster enlargement of an area of the brain (ventricle enlargement), which is a marker for brain aging and neurodegenerative diseases; they also exhibited evidence of a faster decline in their measured cognitive performance. The study was not designed to indicate how much sleep is optimal.
Earlier research suggests that seven hours of sleep per day for adults seems to be the sweet spot for optimal performance on computer based cognitive tests. In coming years, these scientists hope to determine what amount of sleep is good for cardio-metabolic and long term brain health as well. This study was published in the July 1, 2014 issue of the journal Sleep. The full report can be downloaded at https://tinyurl.com/p3b67vv for an $8.00 fee.
DID YOU KNOW…?
People who drink herbal tea even as little as once a week may have a reduced risk of distal colon cancer, according to a 2014 study in the Journal of Epidemiology.
RUNNING A FEW MINUTES DAILY IS AS BENEFICIAL AS RUNNING LONGER
Researchers have concluded that runners may live an average of three years longer than people who do not run and that you can reap this benefit even if you pursue slow running and even for mere minutes every day. (Current guidelines for physical activity call for a minimum of 75 minutes per week of running or other vigorous-intensity aerobic activity, or 30 minutes of moderate-intensity exercise most days of the week. However, this study found much shorter time spent is as effective.)
People who regularly ran less than an hour per week reduced their risk of death just as much as runners who logged three hours or more weekly. In fact, longer and faster running times appeared to be less beneficial for heart health. Overall, running was linked to a 30% lower risk of death from any cause and a 45% lower risk of death from heart disease or stroke, compared to not running. But running a minimum 30 minutes to 59 minutes each week, which equates to just 5 to 10 minutes a day, was associated with a 28% lower overall risk of death and a 58% reduced risk of death from heart disease, compared with not running. Solid benefits were also seen among those who ran fewer than 6 miles a week, who ran slower than 6 miles per hour, or who ran only one to two times a week.
Remarkably, mortality benefits in runners were similar for all running times, distances, frequencies, speed, and for walkers versus runners. The study noted that running has more potential for injury than walking, including joint problems, ankle sprains, shin splints, back pain and muscle pulls, but walking does take more time to get the same amount of exercise. There is no proof that longer lifespan is directly caused by running. It could be that already healthy people are the ones who choose to run, although the investigators tried to account for such factors, including weight, smoking, drinking or health problems.
The study involved more than 55,000 adults aged 18 to 100, who were followed during a 15-year period; about one quarter of this group were runners. This research was published in the August 5, 2014 issue of the Journal of the American College of Cardiology. The full report can be downloaded at https://tinyurl.com/mt78xeq with access fee.
A HEALTHY LIFESTYLE MAY HELP PREVENT DEMENTIA
A new study found that seniors at risk for dementia may help safeguard their memory and ability to think by adopting a healthier lifestyle. Older people who began eating right, exercising, playing brain games, and socializing more often performed better on memory and problem-solving tests than people who maintained their habits. (Earlier studies have observed that each of these changes might help fight dementia, but this is the first randomized clinical trial to put those findings to the test.)
This is the first study to definitively show that changing your lifestyle will reduce your risk for cognitive decline. The study involved 1,260 people aged 60 to 77 at risk for dementia and Alzheimer’s disease. Half of the participants received nutritional guidance, physical exercise, brain training, social activities, and management of heart health risk factors. The other half just received regular health advice.
After two years, the group that underwent lifestyle changes performed significantly better on memory tests, problem-solving exercises and quick-thinking quizzes. The researchers stressed that healthy lifestyle is not a guarantee that memory and cognitive function will not decline, but it may reduced the overall risk.
These findings were presented July 17, 2014 at the Alzheimer’s Association International Conference in Copenhagen. The study has not yet been posted online or published.
CHOLESTEROL NOW SHOWN TO TRIGGER CANCER
A study has found an association between cholesterol and the activation of a signaling pathway that promotes cancer. (Harmful cholesterol levels are linked to heart disease and hardening of the arteries. High-fat diets, which in turn boost cholesterol levels, have been linked to an elevated incidence of cancer. But this research explains how cholesterol actually triggers the start of cancer.)
Cells employ thousands of signaling pathways to conduct their functions. Known as canonical Wnt signaling, this pathway that promotes cell growth and division and is most active in embryonic cells during development. Over-activity of this signaling pathway in mature cells appears to be a major driver in the development of cancer. The scientists discovered a binding site for cholesterol on a specific protein that acts like a switch that passes along signals to produce cells and promote their division, which is how cancer can develop. This may finally explain why elevated cholesterol increases cancer risk, at least those cancers that are driven by the canonical Wnt signaling pathway – a list that includes colon cancer, melanoma, breast cancer and lung cancer.
This study was published July 15, 2014 in the journal Nature Communications. The full-text report is now available online at https://tinyurl.com/ptqq6qw with fee.
DID YOU KNOW…?
• Excessive alcohol use accounts for one in ten deaths among working-age American adults aged 20 to 64, reports the Centers for Disease Control.
• An estimated 5% of all hospital admissions in North America, over 1.1 million a year, are due to drug side effects.
• Children who consume a diet in line with the Mediterranean diet are 15% less likely to be overweight or obese than children who do not.
• New research has found that people with Type 2 diabetes who eat a diet high in salt face a 100% higher risk of cardiovascular disease than diabetics who consume less sodium.https://tinyurl.com/lgh3uzy