Gender Influences on Alzheimer's Disease
Of the estimated 5.4 million Americans affected by Alzheimer's disease and related dementias nearly two thirds are women. There are still major gaps in our understanding of the roles sex and gender play in the onset and progression of Alzheimer's disease. As we learn more through emerging technologies, and refine how studies look at gender issues, we get nearer to finding out their influence.
Brain scan technology is one area making big strides into our understanding of how the brain works and what happens when it becomes diseased. An example is a recent study from the Medical University of South Carolina in Charleston who used magnetic resonance imaging (MRI) brain scans. They found that although all people with Alzheimer's disease lose brain cells, which leads to atrophy (brain shrinking), women with Alzheimer's had greater levels of atrophy in the twelve months prior to their diagnosis. The brain scans also showed that over a five year period of 60 men and 49 women, women lost gray matter volume in different areas with their progression from mild cognitive impairment to Alzheimer's.
Dr. Spampinato and her colleagues also found that the disease developed more aggressively in men and over a shorter period of time.
In another study (August 2012) researchers at the University of Hertfordshire found women with Alzheimer's showed worse mental deterioration than men with the disease, even when at the same stage of the condition. Published in the Journal of Clinical and Experimental Neuropsychology Professor Laws and his team looked at data from 15 published studies and found that women did worse than men when they looked at their verbal skills, a skill where women consistently out perform men. Visiospacial skills, an example of which is the ability to accurately reach for objects in our visual field and shift our gaze to a different point, was also worse in women with AD. Women also performed less well in tests on certain types of memory-semantic memory (that includes general knowledge), and in episodic memory (ability to recall specific events of our own past). These two types of memory together make up the category of declarative memory, which is one of the two major divisions in memory.
Behaviors seen in Alzheimer's disease also seem to differ between men and women. In an older, but still interesting study, 75 women and fifty men from the outpatient dementia clinics of Roger Williams Hospital and Miriam Hospital in Providence, Rhode Island were observed. It was found that the behavior of men and women with AD differed frequently and were particularly marked. Men, for example, seemed more prone to apathy and women to emotional lability (mood changes) and to reclusiveness.
In another study researchers wanted to look at the gender differences of behavior in nursing home residents as predictors of differences in medication use with psychoactive drugs. They found that gender does play an important role in the use of potent tranquillizers. Even given that the use of psychoactive drugs is apparently now being discouraged, they were found to be used more in men as they exhibited more problems with wandering, abusiveness, and socially inappropriate behaviors. Interestingly this study found hallucinations and delusions as well as depression were equally prevalent in men and women.
Gender is becoming an increasingly important area of study into diseases such as Alzheimer's. Differences or similarities between men and women in the onset and progression of dementia may all help pharmaceutical companies develop relevant and targeted treatments.
Radiological Society of North America (2012, November 26). Researchers discover gender-based differences in Alzheimer's disease. ScienceDaily. Retrieved December 7, 2012, from http://www.sciencedaily.com /releases/2012/11/121126110747.htm
Christine L. Carter, Eileen M. Resnick, Monica Mallampalli, Anna Kalbarczyk. Sex and Gender Differences in Alzheimer's Disease: Recommendations for Future Research. Journal of Women's Health, 2012; 120823092801005 DOI: 10.1089/jwh.2012.3789
Tate C.A, Gordon N.M, Heindel W.C. Gender differences in the behavioral manifestations of Alzheimer's disease. Journal of the American Geriatrics Society. 1996, 44(5):583-587
University of Hertfordshire (2012, August 23). Women with Alzheimer's deteriorate faster than men. ScienceDaily. Retrieved December 7, 2012, from http://www.sciencedaily.com /releases/2012/08/120824082515.htm
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