Common prostate cancer treatment linked to later dementia, researcher says

A new retrospective study of patient medical records suggests that men with prostate cancer who are treated with testosterone-lowering drugs are twice as likely to develop dementia within five years as prostate cancer patients whose testosterone levels are not tampered with.

The study, by researchers at the Stanford University School of Medicine and the University of Pennsylvania Perelman School of Medicine, also demonstrates emerging techniques for extracting biomedical data from ordinary patient medical records.

The paper describing the research will be published online Oct. 13 in JAMA Oncology. Kevin Nead, MD, DPhil, a resident at the University of Pennsylvania who got his medical degree at Stanford, is the lead author. Nigam Shah, MBBS, PhD, associate professor of biomedical informatics research at Stanford, is the senior author.

Testosterone can promote the growth of prostate tumors, and so clinicians have used androgen deprivation therapy to lower testosterone and other androgens in prostate cancer patients since the 1940s. In the United States, about a half-million men currently receive ADT as a treatment for prostate cancer.

'The risk is real'

A 2015 study by the same authors found an association between ADT and Alzheimer's disease. In the new paper, the team expanded their work to include several other forms of dementia. "When we published our last paper, a letter to the editor pointed out that Alzheimer's is often confused with vascular dementia," said Shah. "So instead of looking for Alzheimer's and dementia separately, we decided to aggregate them into a higher-level category -- all dementias and cognitive decline." Such aggregation could minimize the question of misdiagnosis, Shah said, and increase the sample size to provide more statistical power.

The team looked at deidentified records from Stanford Medicine's clinical-research data warehouse for nearly 10,000 patients with prostate cancer. Of the 1,829 who received androgen deprivation therapy, 7.9 percent developed dementia within five years, compared with 3.5 percent of those not treated with ADT.

"The risk is real and, depending on the prior dementia history of the patient, we may want to consider alternative treatment, particularly in light of a recent prospective study from the U.K.," said Shah. That study, published in September in The New England Journal of Medicine, revealed that prostate cancer patients randomized to either active monitoring, surgery or radiation therapy all had the same risk of death from the cancer after 10 years. Ninety-nine percent of men in the study survived regardless of initial treatment. These startling results suggest that active monitoring of prostate cancer patients may be as good as early radical treatment and may cause fewer side effects.

And because the actual number of patients possibly at risk for dementia from androgen deprivation therapy is small, it makes sense when weighing the value of prescribing ADT to try to identify which prostate cancer patients might be vulnerable to dementia, said Shah.

The new study adds to a growing body of evidence supporting Stanford Medicine's precision health approach, the goal of which is to anticipate and prevent disease in the healthy and precisely diagnose and treat disease in the ill.

Nead and Shah cautioned that prostate cancer patients who are receiving ADT shouldn't make changes to their medications without talking to their physicians.

"I was surprised at how ubiquitous the effects on all types of dementia were, but I would definitely not alter clinical care based on our results," Nead said. He added that he would like to see a prospective, randomized clinical trial to establish whether ADT can be more firmly linked to an increased risk of dementia and to help identify what kinds of patients might be vulnerable to that increased risk, he said. He anticipates that checking for dementia risk in people treated with ADT will be part of future randomized, clinical trials that have a larger focus.

Retrospective complements prospective

The new retrospective study of patient records took only a few weeks, said Shah. "We are working to make such studies as simple as a Google search," he said. "We were down to weeks in this one, and our current efforts, which are funded by the Dean's Office, have gotten us close to two to three days."

In contrast, a prospective, randomized clinical trial to study the same question would probably require thousands of patients, years to complete and many millions of dollars, said Kenneth Mahaffey, MD, a Stanford professor of medicine who was not involved in the study.

Studies of existing patient health records are far cheaper and faster than "gold standard" randomized, clinical prospective studies. And patient health record studies offer powerful ways to identify hypotheses about efficacy and safety that are worth further testing in clinical trials, said Mahaffey, who is vice chair of clinical research in Stanford's Department of Medicine.

But the lack of randomization in health record studies means the results can be misleading, cautioned Mahaffey. "This work is important," he said, "but there are a number of examples of such retrospective studies where the results have been completely wrong."

Shah said the approach his team used minimized the chance of being wrong. For example, the authors matched patients who received ADT and those who did not according to how sick they were. They also explicitly and empirically quantified the chance of being wrong by testing associations they knew were not true, calibrating their approach.

Retrospective studies of patient medical records aren't meant to replace randomized clinical trials, said Shah. "If we had infinite funding, we'd do a trial for everything. But we don't have that," he said. "These cheap, few-week studies can guide us where to point our clinical trial dollars."

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Story Source:

Materials provided by Stanford University Medical Center. Original written by Jennie Dusheck. Note: Content may be edited for style and length.

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Journal Reference:

1. Kevin T. Nead, Greg Gaskin, Cariad Chester, Samuel Swisher-McClure, Nicholas J. Leeper, Nigam H. Shah.Association Between Androgen Deprivation Therapy and Risk of Dementia. JAMA Oncology, 2016; DOI:10.1001/jamaoncol.2016.3662

Factors secreted by gut bacteria may help combat kidney stones

Researchers have discovered that factors secreted by gut bacteria might help prevent or treat kidney stones. The findings appear in an upcoming issue of the Journal of the American Society of Nephrology (JASN).

Kidney stones can pose serious health problems for people and can increase their risks of developing chronic kidney disease and kidney failure. Oxalate is a small anion that can complex with calcium to form calcium oxalate kidney stones under certain conditions, and elevated urinary excretion of oxalate can be an indicator of increased risk. The intestines play a crucial role in oxalate balance, and Oxalobacter formigenes (Of) is an anaerobic bacterium that lives in the large intestine and utilizes oxalate as its exclusive energy source.

When studying this bacterium, Hatim Hassan, MD, PhD (University of Chicago) and his colleagues found that factors secreted by Of can stimulate oxalate transport by human intestinal cells grown in tissue culture. The team also revealed that the mechanisms of the observed stimulation involve the PKA signaling pathway and a protein transporter called SLC26A6. Importantly, Of factors reduced urinary oxalate excretion by >32.5% in mice by stimulating colonic oxalate secretion.

"Probiotic bacteria have several health benefits; however, the difficulties in determining intestinal bacterial bioavailability and biosafety concerns when administering live probiotics are potential problems facing current probiotics clinical applications. Developing probiotics-derived factors as novel therapeutic agents is an alternative approach that addresses such concerns," said Dr. Hassan. "The fact that these factors retain their biological activity and can effectively reduce urinary oxalate excretion in mice indicates their significant potential as novel therapeutic agents, and provides a compelling reason for the aggressive pursuit of their characterization, which is currently underway."

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Story Source:

Materials provided by American Society of Nephrology (ASN).Note: Content may be edited for style and length.

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Journal Reference:

1. D. Arvans, Y.-C. Jung, D. Antonopoulos, J. Koval, I. Granja, M. Bashir, E. Karrar, J. Roy-Chowdhury, M. Musch, J. Asplin, E. Chang, H. Hassan. Oxalobacter formigenes-Derived Bioactive Factors Stimulate Oxalate Transport by Intestinal Epithelial Cells. Journal of the American Society of Nephrology, 2016; DOI: 10.1681/ASN.2016020132

Body Nutrition

Starches for vitality: Carbohydrates are your principle wellspring of vitality. Your starches originate from natural fiber-rich sustenances, for example, entire grains, organic product, vegetables, potatoes, chestnut rice and sweet corn that give ease back vitality discharge to your workout prerequisites. The sugars in this frame accompany fiber, supplements, vitamins and minerals. For the fundamental suppers, it is suggested that you eat a partition of sugar the span of your clench hand together with protein and some solid fat, for example, rice and beans. Go moderate on scones, cakes, sweetened grains that have high glycaemic record.

Protein for muscle development: Muscle development requires protein and the individuals who workout require more protein than latent individuals. Eliminating protein can bring about weakness and back off your recuperation procedure after activities. Have a clench hand measured partition of incline protein for principle dinner, for example, angle, incline meat, chicken, eggs, soya and nuts. Protein nourishments give amino acids to development muscle. Amino acids can be found in creature proteins while plant proteins contain littler sums.

Sound fat for tissues: Monounsaturated fats, for example, olive oil, nuts and seeds in addition to Omega 3 fats, for example, angle oil and walnuts can expand the conveyance of oxygen to muscles, enhance your continuance and help you to smolder body fats. Eliminated soaked (creature) fats and palm oil based items. By adjusting your fats allow along these lines won't just help your weight loss exercises additionally can enhance oxygen conveyance to your cells, enhance your digestion system and lower your blood cholesterol.

Eat your greens and organic products. The more exceptional the shade of the organic products the more noteworthy the cancer prevention agent and shield your body from degenerative ailments. It additionally helps your resistance and battle hurtful microscopic organisms and infections in your body. All in all, get the dietary adjust right and you will have enough vitality to see you through your weight loss workout and accomplish the wanted results so as to come.

New research finds decrease in brain blood flow after stopping exercise in healthy older adults

We all know that we can quickly lose cardiovascular endurance if we stop exercising for a few weeks, but what impact does the cessation of exercise have on our brains? New research led by University of Maryland School of Public Health researchers examined cerebral blood flow in healthy, physically fit older adults (ages 50-80 years) before and after a 10-day period during which they stopped all exercise. Using MRI brain imaging techniques, they found a significant decrease in blood flow to several brain regions, including the hippocampus, after they stopped their exercise routines.

"We know that the hippocampus plays an important role in learning and memory and is one of the first brain regions to shrink in people with Alzheimer's disease," says Dr. J. Carson Smith, associate professor of kinesiology and lead author of the study, which is published in Frontiers in Aging Neuroscience in August 2016. "In rodents, the hippocampus responds to exercise training by increasing the growth of new blood vessels and new neurons, and in older people, exercise can help protect the hippocampus from shrinking. So, it is significant that people who stopped exercising for only 10 days showed a decrease in brain blood flow in brain regions that are important for maintaining brain health."

The study participants were all "master athletes," defined as people between the ages of 50 and 80 (average age was 61) who have at least 15 years history of participating in endurance exercise and who have recently competed in an endurance event. Their exercise regimens must have entailed at least four hours of high intensity endurance training each week. On average, they were running ~36 miles (59 km) each week or the equivalent of a 10K run a day! Not surprisingly, this group had a V02 max above 90% for their age. This is a measure of the maximal rate of oxygen consumption of an individual and reflects their aerobic physical fitness.

"We know that if you are less physically active, you are more likely to have cognitive problems and dementia as you age," says Dr. Smith. "However, we did not find any evidence that cognitive abilities worsened after stopping exercising for just 10 days. But the take home message is simple - if you do stop exercising for 10 days, just as you will quickly lose your cardiovascular fitness, you will also experience a decrease in blood brain flow."Dr. Smith and colleagues measured the velocity of blood flow in brain with an MRI scan while they were still following their regular training routine (at peak fitness) and again after 10 days of no exercise. They found that resting cerebral blood flow significantly decreased in eight brain regions, including the areas of the left and right hippocampus and several regions known to be part of the brain's "default mode network" - a neural network known to deteriorate quickly with a diagnosis of Alzheimer's disease. This information adds to the growing scientific understanding of the impact of physical activity on cognitive health.

Dr. Smith believes that this could have important implications for brain health in older adults, and points to the need for more research to understand how fast these changes occur, what the long term effects could be, and how fast they could be reversed when exercise is resumed.

Source:

University of Maryland

Obese individuals who consume aspartame may have worse glucose management

Artificial sweeteners help individuals with obesity to cut calories and lose weight but may have negative health effects, according to researchers at York University's Faculty of Health.

"Our study shows that individuals with obesity who consume artificial sweeteners, particularly aspartame, may have worse glucose management than those who don't take sugar substitutes," says Professor Jennifer Kuk, obesity researcher in the School of Kinesiology and Health Science.

Normally, weight loss is associated with several improvements in health. Artificial sweeteners are often used to help individuals cut calories and manage their weight as they are not digested by the body. However, the recent study suggests that the bacteria in the gut may be able to break down artificial sweeteners, resulting in negative health effects.

Currently, there are many new sugar substitutes that are used in foods. The researchers note that further investigation is needed to determine if there are any health effects of using these sweeteners."We didn't find this adverse effect in those consuming saccharin or natural sugars," says Kuk. "We will need to do future studies to determine whether any potentially negative health effects of artificial sweeteners outweigh the benefits for obesity reduction."

For the study, data from 2856 U.S. adults from the Third National Health and Nutrition Survey (NHANES III) was used. Individuals reported their diet over the past 24 hours and were categorized as consumers of artificial sweeteners (aspartame or saccharin), or high or low consumers of natural sugars (sugar or fructose). Diabetes risk was measured as the ability to manage blood sugars using an oral glucose tolerance test.

Source:

York University

Exercise can help improve ADHD symptoms in adults

Exercise, even a small amount, can help alleviate symptoms of ADHD in adults, according to a new study by University of Georgia researchers.

The study, released this month in the journal Medicine and Science in Sports and Exercise, found a single bout of exercise has psychological benefits for adults with these elevated ADHD symptoms. About 6 percent of American adults report symptoms consistent with attention deficit hyperactivity disorder, or ADHD, which lead to anxiety, depression, low energy and motivation, poor performance at work or school and also increased traffic accidents.

"Exercise is already known as a stress reducer and mood booster, so it really has the potential to help those suffering with ADHD symptoms," said the study's senior author Patrick O'Connor, professor in the UGA College of Education's kinesiology department. "And while prescription drugs can be used to treat these symptoms, there's an increased risk of abuse or dependence and negative side effects. Those risks don't exist with exercise."

As a result, researchers found that it was only after the exercise when the participants felt motivated to do the task; they also felt less confused and fatigued and instead felt more energetic. Interestingly, leg movements and performance on the task did not change after the exercise—rather, the exercise helped the young men feel better about doing the task.The study tested 32 young men with elevated ADHD symptoms who cycled at a moderate intensity for 20 minutes on one day, and on another day sat and rested for 20 minutes as a control condition. The participants were asked to perform a task requiring focus both before and after the different conditions, and researchers noted leg movement, mood, attention and self-reported motivation to perform the task.

These findings are consistent with prior research that shows a single bout of exercise helps people feel more energetic, said O'Connor, who is also co-director of the UGA Exercise Psychology Laboratory. The results suggest that young men who have symptoms of ADHD can benefit psychologically from the short workouts, similar to the benefits enjoyed by typical adults who work out.

"The reduced feelings of confusion and increased motivation to perform a cognitive task suggest that other types of acute exercise also may benefit cognitive performance," added study co-author Kathryn Fritz, a UGA doctoral student who completed the study as part of her master's thesis. "We speculate that a different mode or duration or intensity of exercise, other than a boring cycle ride in a sterile lab, may show larger cognitive effects for those suffering from ADHD symptoms."

Source:

University of Georgia

Lifting lighter weights many times can be effective alternative way to gain muscle strength

New research from McMaster University is challenging traditional workout wisdom, suggesting that lifting lighter weights many times is as efficient as lifting heavy weights for fewer repetitions.
It is the latest in a series of studies that started in 2010, contradicting the decades-old message that the best way to build muscle is to lift heavy weights.
"Fatigue is the great equalizer here," says Stuart Phillips, senior author on the study and professor in the Department of Kinesiology. "Lift to the point of exhaustion and it doesn't matter whether the weights are heavy or light."
Researchers recruited two groups of men for the study--all of them experienced weight lifters--who followed a 12-week, whole-body protocol. One group lifted lighter weights (up to 50 per cent of maximum strength) for sets ranging from 20 to 25 repetitions. The other group lifted heavier weights (up to 90 per cent of maximum strength) for eight to 12 repetitions. Both groups lifted to the point of failure.

"At the point of fatigue, both groups would have been trying to maximally activate their muscle fibres to generate force," says Phillips, who conducted the work with graduate students and co-authors Rob Morton and Sara Oikawa.Researchers analyzed muscle and blood samples and found gains in muscle mass and muscle fibre size, a key measure of strength, were virtually identical.
While researchers stress that elite athletes are unlikely to adopt this training regime, it is an effective way to get stronger, put on muscle and generally improve health.
"For the 'mere mortal' who wants to get stronger, we've shown that you can take a break from lifting heavy weights and not compromise any gains," says Phillips. "It's also a new choice which could appeal to the masses and get people to take up something they should be doing for their health."
Another key finding was that none of the strength or muscle growth were related to testosterone or growth hormone, which many believe are responsible for such gains.
"It's a complete falsehood that the short-lived rise in testosterone or growth hormone is a driver of muscle growth," says Morton. "It's just time to end that kind of thinking."
Researchers suggest, however, that more work remains to be done in this area, including what underlying mechanisms are at work and in what populations does this sort of program work.

Source:

McMaster University

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Tags: Blood, Cell, Fatigue, Growth Hormone, Hormone, Kinesiology, Muscle, Physiology, Stress,Testosterone