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Published on Leave a comment on Does The Appendix Have A Beneficial Purpose?

 More research supporting that the appendix has a purpose - that it has an immune function and is a "reservoir" for beneficial gut bacteria. That is, it is where beneficial bacteria go and hide out when the person has food poisoning or is taking antibiotics (which wipe out bacteria in the gut), and then these bacteria replenish the gut afterwards. (Other supporting research.) This is the opposite of what many have believed for years (and we were taught in school) - which was that it is something that may have had a purpose long ago, but now is a "vestigial organ" and useless in humans. Hah! Once again scientific knowledge is being rewritten.

The researchers examined 533 mammal species for the presence of an appendix, and found it in a number of them, including humans, chimps, and dogs. From Science Daily:

Appendix may have important function, new research suggests

The human appendix, a narrow pouch that projects off the cecum in the digestive system, has a notorious reputation for its tendency to become inflamed (appendicitis), often resulting in surgical removal. Although it is widely viewed as a vestigial organ with little known function, recent research suggests that the appendix may serve an important purpose. In particular, it may serve as a reservoir for beneficial gut bacteria. Several other mammal species also have an appendix, and studying how it evolved and functions in these species may shed light on this mysterious organ in humans.

Heather F. Smith, Ph.D., Associate Professor, Midwestern University Arizona College of Osteopathic Medicine, is currently studying the evolution of the appendix across mammals. Dr. Smith's international research team gathered data on the presence or absence of the appendix and other gastrointestinal and environmental traits for 533 mammal species. 

They discovered that the appendix has evolved independently in several mammal lineages, over 30 separate times, and almost never disappears from a lineage once it has appeared. This suggests that the appendix likely serves an adaptive purpose. Looking at ecological factors, such as diet, climate, how social a species is, and where it lives, they were able to reject several previously proposed hypotheses that have attempted to link the appendix to dietary or environmental factors. Instead, they found that species with an appendix have higher average concentrations of lymphoid (immune) tissue in the cecum. This finding suggests that the appendix may play an important role as a secondary immune organ. Lymphatic tissue can also stimulate growth of some types of beneficial gut bacteria, providing further evidence that the appendix may serve as a "safe house" for helpful gut bacteria.

 Drawing of colon seen from front (the appendix is colored red). From Wikipedia

Published on Leave a comment on Breast Cancer Study Finds A Lot of Overdiagnosis

Another large study looking at screening mammograms for breast cancer has raised the issue of overdiagnosis and overtreatment once again. The purpose of mammography screening is to find cancer when it is small and so prevent cancer from growing and becoming advanced cancer. However, the researchers did not find this - there was a major increase in finding small cancers (the kind that may grow so slowly as to never cause any problems or that may even regress), but the rate of advanced cancers stayed the same.

The problem of overdiagnosis (finding small tumors that may never cause problems) and overtreatment (treating unnecessarily), which is leading to medical experts "rethinking cancer screening" is a major shift in how cancer screening is being viewed for a number of cancers. This is because studies show that overall death rates are basically the same in screened vs non-screened persons for mammography, colon, prostate, and lung cancer screening (see post). The view of how cancer grows and spreads may have to be reexamined and changed. One possibility suggested by Dr. H. Gilbert Welch is that aggressive cancer is already "a systemic disease by the time it's detectable" (Oct. 28, 2015 post).

The following excerpts are from the thoughtful review of the study in Health News Review: Overdiagnosis of ductal carcinoma in situ: ‘the pathology equivalent of racial profiling’

Danish researchers are providing new evidence that many breast cancers found via screening mammograms don’t need to be treated. Women with these non-threatening tumors are said to be “overdiagnosed” with breast cancer. Overdiagnosis occurs when breast screening such as mammography detects small, slow-growing cancers that may never cause the patient any trouble. Yet, women diagnosed with such tumors are exposed to very real harms–possible surgery, chemotherapy, radiation, and living life as a “cancer patient.”

How much overdiagnosis are we talking about? If you don’t include cases of ductal carcinoma in situ (DCIS) in the tallies, anywhere from 14.7% to 38.6% of breast cancers found via screening represent overdiagnosis, the study authors found. The rate ranges from 24.4% to as high as 48.3% when DCIS is included.

DCIS is a collection of abnormal cells inside a milk duct that may–but usually doesn’t–break out to become invasive and potentially lethal cancer. About 60,000 women are told they have DCIS each year in the United States. Some experts estimate that up to 80% of women with DCIS found via screening may not need any treatment at all–and instead should just keep an eye on things. Obviously, women need to be fully and accurately informed about the benefits and risks — including the risk of overdiagnosis — before embarking on any decision to get screened for breast cancer or choosing a course of action following a diagnosis.

Otis Brawley, MD, Chief Medical Officer for the American Cancer Society, says it’s been difficult for modern medicine to wrap its brain around the concept of overdiagnosis. The natural inclination is to assume that cancerous-looking cells “will grow, spread, and eventually kill,” he writes in an editorial accompanying the Danish study. “However, some of these lesions may be genomically predetermined to grow no further and may even regress. In many respects, considering all small breast lesions to be deadly and aggressive types of cancer is the pathologic equivalent of racial profiling.

Excerpts from the original study from the Annals of Internal Medicine: Breast Cancer Screening in Denmark: A Cohort Study of Tumor Size and Overdiagnosis

Background: Effective breast cancer screening should detect early-stage cancer and prevent advanced disease. Objective: To assess the association between screening and the size of detected tumors and to estimate overdiagnosis (detection of tumors that would not become clinically relevant).... Setting: Denmark from 1980 to 2010. Participants: Women aged 35 to 84 years. Intervention: Screening programs offering biennial mammography for women aged 50 to 69 years beginning in different regions at different times.

Conclusion: Breast cancer screening was not associated with a reduction in the incidence of advanced cancer. It is likely that 1 in every 3 invasive tumors and cases of DCIS (ductal carcinoma in situ) diagnosed in women offered screening represent overdiagnosis (incidence increase of 48.3%).

Breast screening is associated with a substantial increase in the incidence of nonadvanced tumors and DCIS (ductal carcinoma in situ) in Denmark but not with a reduction in the incidence of advanced tumors, and the overdiagnosis rate is substantial. These findings support that screening has not accomplished the promise of a reduction in invasive therapy or disease-specific mortality.

Published on Leave a comment on Vitamin D and Frequent Headaches

I saw mention of this study in a number of places - that low vitamin D levels are linked to chronic headaches. A little too soon to know if that is really true -  the researchers in this study looked at the blood vitamin D levels of 2601 men just one time, and did not give vitamin D supplements to the men to see if this changed the frequency of migraine headaches. The researchers themselves pointed out that other studies looking at this same issue have had mixed results. And they themselves pointed out that low blood levels of vitamin D (serum 25(OH)D concentration) was associated with a markedly higher risk of frequent headache in men. Associated does not mean caused.

Yes, low vitamin D levels is linked to a number of health problems (see all vitamin D posts). But at this point I think that it's a case of "wait and see" to see if vitamin D levels have something to do with headache frequency. Perhaps other micronutrients are important, perhaps something else. Note that in the study they used below 50 nmol as the measure for low vitamin D levels. In the USA, that translates into below 20 ng/ml, which everyone agrees is too low (a deficiency). The best source of vitamin D is sunlight - which is why it's called the "sunshine vitamin". From Science Daily:

Vitamin D deficiency increases risk of chronic headache

Vitamin D deficiency may increase the risk of chronic headache, according to a new study from the University of Eastern Finland....The Kuopio Ischaemic Heart Disease Risk Factor Study, KIHD, analysed the serum vitamin D levels and occurrence of headache in approximately 2,600 men aged between 42 and 60 years in 1984-1989. In 68% of these men, the serum vitamin D level was below 50 nmol/l, which is generally considered the threshold for vitamin D deficiency. Chronic headache occurring at least on a weekly basis was reported by 250 men, and men reporting chronic headache had lower serum vitamin D levels than others.

When the study population was divided into four groups based on their serum vitamin D levels, the group with the lowest levels had over a twofold risk of chronic headache in comparison to the group with the highest levels. Chronic headache was also more frequently reported by men who were examined outside the summer months of June through September. Thanks to UVB radiation from the sun, the average serum vitamin D levels are higher during the summer months.

The study adds to the accumulating body of evidence linking a low intake of vitamin D to an increased risk of chronic diseases. Low vitamin D levels have been associated with the risk of headache also by some earlier, mainly considerably smaller studies.

Published on Leave a comment on Living Close To Heavy Traffic And Dementia Risk

Another large study has found negative health effects from living close to high-traffic roadways - this time a higher risk of dementia. The closer to the heavy traffic road, the higher the risk - with the highest risk in people living less than 50 meters (164 feet) from a high-traffic roadway, especially in major urban cities.

Other studies suggest that the air pollution from the high-traffic roadways is the problem - that the pollutants from vehicles (such as from the exhaust, and the wear of the tires) get into the body and brain and cause systematic inflammation. (see posts on air pollution and the brain) Traffic-related air pollution includes ultrafine particles, nitrogen oxides, and particles. And the constant noise is stressful. However, this large Canadian study found no association with multiple sclerosis or Parkinson's disease and living close to heavy traffic roadways. (See all posts on air pollution and the brain.) From Science Daily:

Living near major traffic linked to higher risk of dementia

People who live close to high-traffic roadways face a higher risk of developing dementia than those who live further away, new research from Public Health Ontario (PHO) and the Institute for Clinical Evaluative Sciences (ICES) has found. Led by PHO and ICES scientists, the study found that people who lived within 50 metres of high-traffic roads had a seven per cent higher likelihood of developing dementia compared to those who lived more than 300 meters away from busy roads.

Published in The Lancet, the researchers examined records of more than 6.5 million Ontario residents aged 20-85 to investigate the correlation between living close to major roads and dementia, Parkinson's disease and multiple sclerosis....The findings indicate that living close to major roads increased the risk of developing dementia, but not Parkinson's disease or multiple sclerosis, two other major neurological disorders.

"Our study is the first in Canada to suggest that pollutants from heavy, day-to-day traffic are linked to dementia. We know from previous research that air pollutants can get into the blood stream and lead to inflammation, which is linked with cardiovascular disease and possibly other conditions such as diabetes. This study suggests air pollutants that can get into the brain via the blood stream can lead to neurological problems," says Dr. Ray Copes, chief of environmental and occupational health at PHO and an author on the paper.

People who lived within 50 metres of high-traffic roads had a seven per cent higher likelihood of dementia than those who lived more 300 meters away from busy roads. - The increase in the risk of developing dementia went down to four per cent if people lived 50-100 metres from major traffic, and to two per cent if they lived within 101-200 metres. At over 200 metres, there was no elevated risk of dementia. -There was no correlation between major traffic proximity and Parkinson's disease or multiple sclerosis. [Original study]

Published on Leave a comment on Many Countries Ban Spanking, But 19 States Allow Physical Punishment In Schools

A new law in France just banned spanking of children, making it 52 countries in the world that ban spanking of children. Yet in the United States we go so far in the other direction that nineteen states still allow spanking and other forms of physical punishment in school. Of these 19 states, 15 expressly permit it while another four do not prohibit it. According to Federal data, more than 109,000 students were paddled, hit, or physically punished in some way in schools during 2013-2014. Seven Southern states account for 80 percent of in-school corporal punishment in the U.S.: Mississippi, Texas, Alabama, Arkansas, Georgia, Tennessee and Oklahoma.

The National Association of School Psychologists explains corporal punishment as "the intentional infliction of pain or discomfort and/or the use of physical force upon a student with the intention of causing the student to experience bodily pain so as to correct or punish the student's behavior." In other words, it is a spanking, beating, paddling (hitting with a paddle!), or physical abuse.

Also, a recent study found that "black children are twice as likely as white children to be subject to corporal punishment" at school. This is partly because black children tend to live in states where such punishments are allowed, and also because black students are more likely to be singled out for corporal punishment by educators. In Mississippi, white students were physically disciplined at a rate of 4.7 beatings per every 100 students, but among black students, the rate was 8.1 per every 100 students.

Ironically, while Texas is one of the states that allows corporal punishment, research on spanking from the University of Texas (and Univ. of Michigan) found that: the more children are spanked, the more likely they are to defy their parents and to experience increased anti-social behavior, aggression, mental health problems, and cognitive difficulties. These findings are from reviewing 50 years of research on spanking. In other words, study after study found that spanking, corporal punishment, paddling, beatings, physical abuse, or whatever you want to call it - results in negative long-term effects. It causes harm. So why is the USA so damn backward in 2017 that this is still being practiced in schools? The place where children are supposed to be safe, where adults are supposed to be role models, where children are supposed to learn right from wrong. Eh...

From the Washington Post: The States Where Teachers Still Beat Kids

In America's South, the beatings will continue. A new study published today finds that seven Southern states account for 80 percent of in-school corporal punishment in the U.S.: Mississippi, Texas, Alabama, Arkansas, Georgia, Tennessee and Oklahoma. The research by Dick Startz, an economics professor at U.C. Santa Barbara, and released by the Brookings Institution's Brown Center used data from the Department of Education's Civil Rights Division to determine the breakdown.

Corporal punishment at school is illegal in 31 states. Of the 19 that technically allow it, many do not appear to practice it at all, according to Startz' numbers. But some states are use the practice relatively often. In Mississippi there were more than six instances of corporal punishment -- defined as "paddling, spanking, or other forms of physical punishment imposed on a student" -- for every 100 public school students during the 2011-2012 school year. In other words, one out of every 17 public school students in Mississippi can expect to get beaten by a school administrator during a typical school year.

The persistence of corporal punishment is schools is all the more puzzling when you consider the research: "Many studies have shown that physical punishment — including spanking, hitting and other means of causing pain — can lead to increased aggression, antisocial behavior, physical injury and mental health problems for children," the American Psychological Association wrote in 2012. The American Academy of Pediatrics "strongly opposes" the practice. So does the United Nations. These groups agree that the evidence is clear: beating children does far more harm than good.

From University of Texas News: Risks of Harm from Spanking Confirmed by Analysis of Five Decades of Research

The more children are spanked, the more likely they are to defy their parents and to experience increased anti-social behavior, aggression, mental health problems and cognitive difficulties, according to a new meta-analysis of 50 years of research on spanking by experts at The University of Texas at Austin and the University of Michigan. The study, published in this month’s Journal of Family Psychology, looks at five decades of research involving over 160,000 children.

Gershoff and co-author Andrew Grogan-Kaylor, an associate professor at the University of Michigan School of Social Work, found that spanking (defined as an open-handed hit on the behind or extremities) was significantly linked with 13 of the 17 outcomes they examined, all in the direction of detrimental outcomes. “The upshot of the study is that spanking increases the likelihood of a wide variety of undesired outcomes for children. Spanking thus does the opposite of what parents usually want it to do,” Grogan-Kaylor says.

Gershoff and Grogan-Kaylor tested for some long-term effects among adults who were spanked as children. The more they were spanked, the more likely they were to exhibit anti-social behavior and to experience mental health problems. They were also more likely to support physical punishment for their own children, which highlights one of the key ways that attitudes toward physical punishment are passed from generation to generation. The researchers looked at a wide range of studies and noted that spanking was associated with negative outcomes consistently and across all types of studies.... 

Published on Leave a comment on Why Do Some Older Adults Have Youthful Brains?

The beginning of a new year is a time to think about the future, and perhaps think about healthy lifestyles and how to age well. One important issue to think about is: why do some older people have "young" minds while others do not? Can anything be done to improve our odds later in life of being a "superager" and having a youthful, sharp, clear mind?

Unfortunately, as humans age, memory and many other cognitive functions often decline. “Normal” performance on various cognitive tests may be substantially lower than that of a younger adult, but... there is substantial variation in the degree of cognitive decline with age. Some older adults—referred to by some as “superagers”—continue to perform mentally at a level similar to middle-aged adults and sometimes even young adults.

Earlier posts have examined some of the things that help people age well and keep their brains more "youthful" - from diet (here, here, and here), to daily coffee consumption, vitamin D levels (here and here), regular physical activity and exercise (here, here, and here), not living in polluted areas (here and here), civic engagement, higher education, learning new skills, doing arts or crafts, and using a computer (here). Also frequently mentioned are social activities, intellectual stimulation, and genetics.

One recent study (discussed below) found that doing something hard and really challenging (that means forget pleasant puzzles), something that tires you out (whether physically or mentally) is what is good for the brain. So go out and learn a new language or musical instrument, sign up for a course, or anything else that is really challenging - whether physical or mental. Excerpts from a piece written by Lisa F. Barrett, a professor of psychology at Northeastern University, from the NY Times:

How to Become a ‘Superager’

Think about the people in your life who are 65 or older. Some of them are experiencing the usual mental difficulties of old age, like forgetfulness or a dwindling attention span. Yet others somehow manage to remain mentally sharp....Why do some older people remain mentally nimble while others decline? “Superagers” (a term coined by the neurologist Marsel Mesulam) are those whose memory and attention isn’t merely above average for their age, but is actually on par with healthy, active 25-year-olds. My colleagues and I at Massachusetts General Hospital recently studied superagers to understand what made them tick.

Our lab used functional magnetic resonance imaging to scan and compare the brains of 17 superagers with those of other people of similar age. We succeeded in identifying a set of brain regions that distinguished the two groups. These regions were thinner for regular agers, a result of age-related atrophy, but in superagers they were indistinguishable from those of young adults, seemingly untouched by the ravages of time...... The thicker these regions of cortex are, the better a person’s performance on tests of memory and attention, such as memorizing a list of nouns and recalling it 20 minutes later.

Of course, the big question is: How do you become a superager? Which activities, if any, will increase your chances of remaining mentally sharp into old age? We’re still studying this question, but our best answer at the moment is: work hard at something. Many labs have observed that these critical brain regions increase in activity when people perform difficult tasks, whether the effort is physical or mental. You can therefore help keep these regions thick and healthy through vigorous exercise and bouts of strenuous mental effort. My father-in-law, for example, swims every day and plays tournament bridge.

The road to superaging is difficult, though, because these brain regions have another intriguing property: When they increase in activity, you tend to feel pretty bad — tired, stymied, frustrated. Think about the last time you grappled with a math problem or pushed yourself to your physical limits. Hard work makes you feel bad in the moment. The Marine Corps has a motto that embodies this principle: “Pain is weakness leaving the body.” That is, the discomfort of exertion means you’re building muscle and discipline. Superagers are like Marines: They excel at pushing past the temporary unpleasantness of intense effort. Studies suggest that the result is a more youthful brain that helps maintain a sharper memory and a greater ability to pay attention.

This means that pleasant puzzles like Sudoku are not enough to provide the benefits of superaging. Neither are the popular diversions of various “brain game” websites. You must expend enough effort that you feel some “yuck.” Do it till it hurts, and then a bit more.

In the United States, we are obsessed with happiness. But as people get older, research shows, they cultivate happiness by avoiding unpleasant situations. This is sometimes a good idea, as when you avoid a rude neighbor. But if people consistently sidestep the discomfort of mental effort or physical exertion, this restraint can be detrimental to the brain. All brain tissue gets thinner from disuse. If you don’t use it, you lose it. So, make a New Year’s resolution to take up a challenging activity. Learn a foreign language. Take an online college course. Master a musical instrument. Work that brain. Make it a year to remember. [Original study]

Published on Leave a comment on A Medical Device Can Sniff Out Multiple Diseases?

 Image result for breathing mouth What if you could detect cancer by a gadget that can sniff for cancer or some other disease? The theory that disease is detectable from exhaled breath dates back to about 400 BC when the Greek physician Hippocrates used to smell his patients' breath to find out what ailed them. More recently a number of individual diseases, such as diabetes, have been detected with "breath analysis".

But Israeli scientist Hossam Haick and others wanted to invent a medical diagnostic tool (an "electronic nose") that could detect multiple diseases, including cancer, by "sniffing" a patient’s exhaled breath. They recently published a study suggesting that such a device that they developed can work for 17 diseases (including 8 types of cancer, Crohn's disease, ulcerative colitis, irritable bowel syndrome, Parkinson's disease, multiple sclerosis, pre-eclampsia in pregnant women, and chronic kidney failure). The results showed that each of these diseases has its own unique "breathprint", and which overall could be detected with 86% accuracy using the device.

The study used breath samples collected from 1,404 people from 2011 to 2014 in 5 countries (Israel, the United States, Latvia, China, and France). The test subjects were either known to be healthy or to be suffering from one of the 17 diseases. Please note that this diagnostic tool is currently being further researched and developed. It is not available yet.

From Science Daily: Nanoarray sniffs out and distinguishes multiple diseases

Before modern medical lab techniques became available, doctors diagnosed some diseases by smelling a patient's breath. Scientists have been working for years to develop analytical instruments that can mimic this sniff-and-diagnose ability. Now, researchers report in the journal ACS Nano that they have identified a unique "breathprint" for each disease. Using this information, they have designed a device that screens breath samples to classify and diagnose several types of diseases.

Exhaled breath contains nitrogen, carbon dioxide and oxygen, as well as a small amount of more than 100 other volatile chemical components. The relative amounts of these substances vary depending on the state of a person's health. As far back as around 400 B.C., Hippocrates told his students to "smell your patients' breath" to search for clues of diseases such as diabetes (which creates a sweet smell). In more recent times, several teams of scientists have developed experimental breath analyzers, but most of these instruments focus on a single type of disease, such as cancer. In their own work, Hossam Haick and a team of collaborators in 14 clinical departments worldwide wanted to create a breathalyzer that could distinguish among multiple diseases.

The researchers developed an array of nanoscale sensors to detect the individual components in thousands of breath samples from patients who were either healthy or had one of 17 different diseases, such as kidney cancer or Parkinson's disease. By analyzing the results with artificial intelligence techniques, the team could use the array to classify and diagnose the conditions. The team used mass spectrometry to identify the breath components associated with the diseases. They found that each disease produces a unique volatile chemical breathprint, based on differing amounts of 13 components. They also showed that the presence of one disease would not prevent the detection of others -- a prerequisite for developing a practical device to screen and diagnose various diseases in a noninvasive, inexpensive and portable manner.

Published on Leave a comment on Focus On Healthy Lifestyle, Not Just On Tests And Screenings

The wonderful blog posts of Dr. John Mandrola (physician, blogger, and columnist at Medscape) are always thoughtful, and this latest points out things a number of studies have pointed out for a while. Which is to stop obsessing or focusing on "preventive tests" and screenings and numbers, and instead focus on a healthy lifestyle - which means getting regular exercise or physical activity, don't smoke cigarettes, maintaining a healthy weight, and eating a healthy diet with lots of fruits, vegetables, nuts, seeds, whole grains, and legumes (think Mediterranean-style diet).

Don't want overdiagnosis and overtreatment (here, here, here, and here). Excerpts from Dr. John M:

I am changing…

The main thing that has changed about me is my views as a doctor, especially when it comes to dealing with people who complain of nothing. Medicine is most pure when we treat people with illness. The infirmed come to us with a problem and we use our intelligence, experience and procedural skills to help them. It’s immensely gratifying. The joy of helping people still negates the stifling burden of administrative nonsense. I’ll do your damn corporate safety modules one more year because helping sick people get well feels so good.

But when people complain of nothing, our first job is to do no harm. I know prevention of disease is better than treating it, but the process of prevention gets dicey. When we prescribe things (screening tests, statins, aspirin, diabetes drugs etc) to people who complain of nothing, we should have the highest evidence these therapies deliver benefit. Too often, we cite eminence rather than evidence.

I’ve come to believe the medical profession is too paternalistic, too arrogant. I fear the medicalization of the human condition. These days, I order fewer tests. Medical tests put people into the “system,” on the metaphorical train of healthcare. This train accelerates quickly, and it’s often hard to get off. Even a simple echo scares me. I could tell you stories.

More often than not, I tell patients to stop checking their “numbers.” If they insist on health numbers, I favor three–the scale, the belt size and a Timex to measure walking speed.

A 2002 article from Dr. David Sackett (a pioneer of evidence-based medicine) perfectly captures my views on preventive medicine. It’s called The Arrogance of Preventive Medicine. It’s worth a look, now more than ever.

Published on Leave a comment on Loss of Smell And Alzheimer’s Disease

Recently some studies have found that a diminished sense of smell occurs in persons with mild cognitive impairment and Alzheimer's disease. Doctors have long observed that patients with Alzheimer's frequently complain that food doesn't taste good anymore (because they can't smell what they are eating). This is because odor signals from the nose are processed in areas of the brain that are among the first to be affected by Alzheimer's disease. It is thought that as dementia starts and progresses, the parts of the brain that distinguish odors start to deteriorate.

This is why various odor tests have been devised. One such odor test (used in the following study) is called "Sniffin Sticks", which tests for 16 odors such as orange, peppermint, leather, banana, garlic, rose, fish, and coffee. However, note that other degenerative brain diseases (including Parkinson's) can also affect odor detection, and the ability to smell can be diminished by smoking, certain head injuries, and even normal aging. From Medical Xpress:

Study confirms 'sniff test' may be useful in diagnosing early Alzheimer's disease

Tests that measure the sense of smell may soon become common in neurologists' offices. Scientists have been finding increasing evidence that the sense of smell declines sharply in the early stages of Alzheimer's, and now a new study from the Perelman School of Medicine at the University of Pennsylvania published today in the Journal of Alzheimer's Disease confirms that administering a simple "sniff test" can enhance the accuracy of diagnosing this dreaded disease. The sniff test also appears to be useful for diagnosing a pre-dementia condition called mild cognitive impairment (MCI), which often progresses to Alzheimer's dementia within a few years.

Roalf and his colleagues used a simple, commercially available test known as the Sniffin' Sticks Odor Identification Test, in which subjects must try to identify 16 different odors. They administered the sniff test, and a standard cognitive test (the Montreal Cognitive Assessment), to 728 elderly people. The subjects had already been evaluated by doctors at Penn with an array of neurological methods, and according to expert consensus had been placed in one of three categories: "healthy older adult," "mild cognitive impairment," or "Alzheimer's dementia." Roalf and his team used the results from the cognitive test alone, or combined with the sniff test, to see how well they identified subjects in each category.

As researchers report, the sniff test added significantly to diagnostic accuracy when combined with the cognitive test. For example, the cognitive test alone correctly classified only 75 percent of people with MCI, but that figure rose to 87 percent when the sniff test results were added. Combining the two tests also enabled more accurate identification of healthy older adults and those with Alzheimer's dementia. The combination even boosted accuracy in assigning people to milder or more advanced categories of MCI.

Prompted by prior studies that have linked a weakening sense of smell to Alzheimer's, doctors in a few larger dementia clinics already have begun to use smell tests in their assessments of elderly patients. Part of the reason the practice has not yet become common is that the tests that seem most useful take too long to administer. 

Published on Leave a comment on Heart Attacks Run In The Family? Healthy Lifestyle Can Really Reduce Risk

 Image result for human heart in human body wikipedia Heart attacks run in the family? Does this mean you are doomed to also have a heart attack? Well, the good news from a large study is that a healthy lifestyle (with at least 3 of these 4 behaviors: not currently smoking, not being obese, regular physical activity at least once per week, and eating a good diet)  lowers the risk of a heart attack by nearly 50% even in those with a high genetic risk for heart attacks. (This is compared to those with an unhealthy lifestyle, which is none or only one healthy behavior.)  In this study a healthy diet was one with lots of fruits, nuts, vegetables, whole grains, fish, and dairy products, and a reduced amount of refined grains, processed meats, red meat, sugar-sweetened beverages, and trans fats.

The researchers also reversed the question and asked: "If you happen to inherit good genes, can a bad lifestyle offset that? We actually found yes." The risk of heart attack is also reduced nearly 50% in those people with good genes and a good lifestyle. BOTTOM LINE: Healthy lifestyle counts, no matter whether heart disease and heart attacks run in the family or not. There is an interaction between the two, From Science Daily:

Following a healthy lifestyle can greatly reduce genetic heart attack risk

It is well known that following a healthy lifestyle -- not smoking, avoiding excess weight and getting regular exercise -- can reduce the risk of heart disease. But what about people who have inherited gene variants known to increase risk? A study led by Massachusetts General Hospital (MGH) investigators has found that, even among those at high genetic risk, following a healthy lifestyle can cut in half the probability of a heart attack or similar event. 

"The basic message of our study is that DNA is not destiny," says Sekar Kathiresan, MD...."Many individuals -- both physicians and members of the general public -- have looked on genetic risk as unavoidable, but for heart attack that does not appear to be the case."  

In order to investigate whether a healthy lifestyle can mitigate genetic risk, the multi-institutional research team analyzed genetic and clinical data from more than 55,000 participants in four large-scale studies. Three of these studies....followed participants for up to 20 years. Each participant in the current analysis was assigned a genetic risk score....The investigators used four AHA-defined lifestyle factors -- no current smoking; lack of obesity (defined as a body mass index less than 30); physical exercise at least once a week; and a healthy dietary pattern -- to determine a lifestyle score, whether participants had a favorable (three or four healthy factors), intermediate (two factors) or unfavorable (one or no healthy factors) lifestyle.

Across all three prospective studies, a higher genetic risk score significantly increased the incidence of coronary events -- as much as 90 percent in those at highest risk. While known risk factors such as a family history and elevated LDL cholesterol were also associated with an elevated genetic risk score, genetic risk was the most powerful contributor to cardiac risk. Similarly, each healthy lifestyle factor reduced risk, and the unfavorable lifestyle group also had higher levels of hypertension, diabetes and other known risk factors upon entering the studies.

Within each genetic risk category, the presence of lifestyle factors significantly altered the risk of coronary events to such an extent that following a favorable lifestyle could reduce the incidence of coronary events by 50 percent in those with the highest genetic risk scores. Among participants in the BioImage study, both genetic and lifestyle factors were independently associated with levels of calcium-containing plaque in the coronary arteries, and healthy lifestyle factors were associated with less extensive plaque within each genetic risk group. [Original study]