There’s No Place Like Home - Unless Where You Live Increases Your Alzheimer’s Risk

by Women's Brain Health Initiative:Rural vs. Urban LivingIf someone asked you whether you would rather live in the city or in the country, you are likely to answer this question without hesitation based on your personal preferences, and whether you enjoy the hustle and bustle of urban centers, or the quiet seclusion of rural living. Are you aware, however, of the impact of each location on your overall health? And that one of these locations, more than the other, can actually increase your risk of developing Alzheimer’s disease?On a basic level, country living offers open space, nature, fresh air, more opportunity for exercise outdoors, and the simplicity of day-to-day life. In the city, there are public transportation systems, attractions, and entertainment, but also confined spaces, crowds, and the pitfalls of traffic congestion and air pollution.Dr. Tom Russ, a Clinical Lecturer at the Center for Clinical Brain Science at the University of Edinburgh, conducted a systematic review of 51 academic papers published over the last few decades and compared the data on the medical records of more than 12,500 people from around the world, including the U.K., U.S., Canada, and even smaller nations like Nigeria and Peru. Dr. Russ and his colleagues found that individuals in rural areas were at a greater risk for Alzheimer’s disease than those in more urban towns and cities.Dr. Russ noted that “rates of dementia as a whole did not differ greatly between rural and urban dwellers, but for Alzheimer's specifically there was a marked difference.” He continued, "we don't really know the mechanism. It could be to do with access to health care, exposure to some unknown substance, socioeconomic factors, or a number of other factors. We're currently looking into this question in more detail. A priority for researchers will be to identify what causes the difference, so that more can be done earlier in life to prevent people from developing the incurable condition.”While researchers continue to explore the relationship between rural living and dementia risk, those in rural areas can try to improve their brain health by engaging in those activities that contribute to better health amongst urban dwellers (such as making healthy food and diet choices, and participating in fitness classes and organized community sports). While rural living can be simple and relaxing, remote locations also create some unique challenges.There are, however, certain identifiable gaps between urban and rural communities that cannot be addressed at an individual level, such as lack of access to medical care and support. The simplicity of living in more rural areas should not equal isolation, loneliness, and lack of accessibility, each of which have other well-documented psychological impacts. As the number of individuals with Alzheimer’s disease continues to climb, efforts towards treatment and prevention are essential.Home to the Largest Population of Alzheimer’s SufferersIn the small village of Yarumal, located in the city of Antioquia in Colombia, there is the highest per capita rate of Alzheimer’s disease in the world. What is so unusual, and making this even more tragic, is that the majority of people in this village who develop Alzheimer’s disease were diagnosed by the age of 45, with some having been diagnosed as young as 32 years of age.Researchers have now discovered that most residents of this village share the same bloodline, and comprise an extended family of more than 5,000 people. Many of the residents have a rare genetic biomarker known as the Paisa mutation that guarantees the individual will develop the disease. While the Paisa mutation is present in only about 2% of the world's Alzheimer's population, in Antioquia, it is present in approximately 30%.The unusually high incidence of early-onset Alzheimer's has thrust this small village to the forefront of global efforts to find a cure for this devastating illness.Yarumal is one of few places in the world where researchers will know, with virtual certainty, that a sizable proportion of individuals will develop Alzheimer’s disease (unlike the more common type of Alzheimer's disease, which may or may not develop in any aging person). Based on the results of a genetic test, researchers not only will know which residents will develop Alzheimer’s disease, but also approximately what age they will get it. Researchers can therefore work with those individuals who carry the Paisa mutation to test treatments before the disease begins to take its toll.In one of the most significant initiatives currently underway, researchers are providing a group of individuals who tested positive for the Paisa mutation with an experimental drug that blocks or slows the formation of amyloid plaques in the brain. The formation of amyloid plaques is thought to contribute to the degradation of the neurons (nerve cells) in the brain and the subsequent symptoms of Alzheimer's disease.This multimillion-dollar drug trial involves leading scientists, pharmaceutical companies, and representatives of the National Institutes of Health (NIH). The trial is led by Dr. Eric Reiman, Executive Director of Banner Alzheimer’s Institute, and one of the leaders of the Alzheimer’s Prevention Initiative.Because the average person develops Alzheimer's disease after the age of 60, prevention trials pose significant logistical problems. "It would take too many healthy volunteers and too many years to evaluate a trial," said Dr. Reiman. "You’d have to wait too long for people to develop Alzheimer's." What sets this drug trial apart is that the patients, most of them in their 30s, will begin treatment long before they show symptoms of the disease.Jason Karlawish, Co-Director of the Penn Memory Center, gave a presentation at Columbia University on March 27, 2017 where he noted that “if the drug works, we will have discovered a way to slow the natural history of decline. It will be proof of concept for a therapy for these patients but as well for the far larger population of patients at risk for Alzheimer’s later in life. With this kind of result, we need to begin to imagine a future when an amyloid test diagnoses Alzheimer’s disease and, in turn, a prescription for a drug that targets amyloid.”In his presentation, Karlawish also commented on the legal, ethical, and social implications of this kind of study. One key ethical challenge for researchers is the repercussions of conducting genetic testing on members of a community that do not have access to genetic counselors. “The standard is not to know. This presents a dilemma. The custom is not to learn your gene result. How can you perform a clinical trial testing a drug in persons who have the gene?” In order to help address this dilemma, a registry and associated study are recruiting both carriers and non-carriers of the gene, so that volunteers can participate in the study without learning their genotype. Additionally, Karlawish advised that “researchers provided healthcare to all participants, and implemented a social plan that will remain post-trial, providing education and care strategies and support … Colombia is working with research to make the plan sustainable after 2022 by providing access to therapy and bringing genetic testing and counseling to the nation.”In terms of what this means for the future, Karlawish concluded, “even if the clinical trial is ineffective, researchers will have raised awareness. If the therapy is effective, a carrier of the ADAD gene mutation could receive an intervention before signs of dementia are present.” The clinical trial is currently active and will run until 2022.The investigative television program 60 Minutes produced a segment entitled “The Alzheimer’s Laboratory” (November 27, 2016) that shared some of the emotional stories of the residents of Antioquia and the daily struggles that they encounter knowing that many of them will develop Alzheimer’s disease – which, for some, includes the decision not to have children.Broadcast journalist Lesley Stahl emphasized that this community is “offering researchers something they have never had before – a way to test whether intervening years before people start having symptoms, might halt the disease in its tracks.Answers are still years away, but with more than a thousand Americans developing Alzheimer’s every day, a way to prevent it cannot come soon enough.” Quite remarkably, these individuals, who come from such a remote area of the world, “have the potential for informing all of us, globally, about a path forward for conquering Alzheimer’s.”LIFESTYLEMaking certain lifestyle choices, particularly when it comes to your diet, can significantly impact your risk for developing Alzheimer’s disease, according to Dr. Michael Greger.In his article entitled “Where are the Lowest Rates of Alzheimer’s in the World,” Dr. Greger warns of the dangers of the so-called “Western diet,” which is characterized by higher intakes of red and processed meat, refined sugars and grains, alcohol, and high-fat dairy products, with minimal intakes of fruits, vegetables, whole grains, nuts, and fish. Mounting evidence from ecological studies indicates that the contemporary Western dietary pattern is strongly associated with negative health outcomes, including an increased risk of developing Alzheimer’s disease.Dr. Greger notes that research has shown that dementia is more a disease of lifestyle than genetics.There is an emerging consensus that the same foods that clog our arteries can also clog our brains. As Dr. Greger observes, “Alzheimer’s rates of Japanese-Americans living in the U.S. are closer to that of Americans than to Japanese. When people move from their homeland to the United States, Alzheimer’s rates can increase dramatically. Therefore, when Africans or Asians live in the United States and adopt a Western diet, their increase in Alzheimer’s risk suggests that it’s not genetics.”Of course, one does not have to move to the West to adopt a Western diet. In a 2014 study published in the Journal of Alzheimer’s Disease, researchers found that changes in Japan’s dietary habits (due to the influx of Western foods) was highly related to the dramatic increase in Alzheimer’s disease, with the same trend being observed in other developing countries and their changes in national diets.The fact that diet is a modifiable factor – one that is within our control to regulate – should make it a relatively easy lifestyle choice to change for the better, not only in an effort to improve our brain health, but also for our overall physical well-being, since diet is a contributing factor to so many other health problems (such as diabetes, high blood pressure, and obesity).Source: MIND OVER MATTER V6