Four New Gene Variants Identified as Risk Factors for Alzheimer’s Disease
In a study of more than 94,000 people, researchers found four gene variants that increase the risk of Alzheimer’s disease (AD). A gene variant is a variation in the DNA sequence in a person’s genome, which is the complete set of genetic material of a person or any organism. These genes, along with others previously recognized as affecting AD risk, appear to work together on the bodily functions that contribute to the disease. The findings underscore other research that identified the role of the protein amyloid and immune system genes. One of the hallmarks of AD are clumps or plaques of amyloid that form on neurons, destroying their function. Another protein called tau also forms tangles in the brains of people with AD. Rudolph Tanzi, PhD, director of the Aging and Genetics Research Unit at Massachusetts General Hospital and part of an international consortium of researchers involved with the study, says the findings both reaffirm amyloid as a key factor in AD and show that there are more innate immune genes that can affect your susceptibility to neuroinflammation, which is inflammation of the nervous system, including brain cells injured by the onset of AD. “Because at the end of the day, plaques and tangles may set the stage, but it’s neuroinflammation that kills enough neurons to get to dementia,” Dr. Tanzi says. He adds that the study’s findings may go a long way in helping identify potential gene targets for medications that may help prevent or treat AD. The study was published in the journal Nature Genetics.
Social Anxiety Disorder Strongly Associated with Alcoholism Risk
Unlike other types of anxiety disorders, social anxiety may have a direct effect on alcoholism, according to a study published recently in the journal Depression & Anxiety. Researchers assessed possible connections between alcoholism and anxiety disorders, including social anxiety disorder, generalized anxiety disorder, panic disorder, agoraphobia (fear of open spaces or situations that might cause panic or helplessness), and other phobias. Social anxiety disorder had the strongest association with alcoholism risk and predicted the onset of alcoholism later in life to a much greater degree than other anxiety problems. The researchers suggest that by effectively diagnosing and treating social anxiety disorder, mental health professionals may also reduce the risk and complications of alcoholism. They noted that many people with social anxiety disorder are not in treatment, leaving them with a heightened vulnerability to complications such as alcohol abuse or addiction. Likewise, individuals dealing with alcohol addiction may benefit from screenings for social anxiety disorder or other mood disorders.
Mounting Depression Symptoms May Increase Odds of Having a Stroke
People who report a high number of depressive symptoms may be at a higher risk of stroke later in life, according to a study being presented this month at the American Academy of Neurology’s annual meeting. The study, sponsored by the National Institute of Neurological Disorders and Stroke, followed 1,104 participants for an average of 14 years. The participants’ average age at the start of the study was 70. None of the people in the study had experienced a stroke when the study began. Researchers had the participants fill out weekly questionnaires about depressive symptoms, such as how often (if at all) they felt sad or if they had a poor appetite or if they felt as though everything they did required great effort. The researchers devised a zero to 60 scoring range for the symptoms, with a score of at least 16 considered to be elevated. During the study, 101 people had a stroke. After adjusting for major stroke risk factors, such as high blood pressure and smoking, researchers found that participants with elevated levels of depression symptoms were 75 percent more likely to have a stroke than people without depression symptoms. The study was observational and does not prove that depression causes strokes. Rather, it suggests that there could be a strong association between depression and stroke risk. And given how many people have depression but go untreated, getting help for this common mood disorder may help reduce the prevalence of stroke, which is the fifth-leading cause of death in the U.S.