Alzheimer's is a devastating degenerative brain disease that affects elderly people. For years, doctors have been trying to uncover its cause; however, recent research may prove the link between Alzheimer's disease and testosterone. While it is still early in research, the discovery may offer new forms of treatment.
Types of Testosterone
Testosterone is the principal male sex hormone, but testosterone is also present in females. However, men produce forty to sixty percent more testosterone than women.
In the body, there are two types of testosterone: free and bound. Bound testosterone is attached to sex hormone binding globulins, or SHBGs. However, when bound to sex hormone--binding globulin, the testosterone does not work as efficiently as it can. According to John Hopkins University's Health Alerts, "free testosterone is a form of the hormone that is not bound to a protein in the blood and is therefore available to body tissue." But testosterone in its free form is also related to Alzheimer's disease.
Research
Not many studies have been done on testosterone levels and Alzheimer's disease. However in 2004, research conducted by Dr. Resnick and Dr. Moffat, with funding from the National Institutes of Health, investigated deficiencies in testosterone and the link to developing Alzheimer's disease. Just under 575 men were tested, all enrolled in the Baltimore Longitudinal Study of Aging and between the ages of 32 and 87. Both free and total testosterone levels were measured for an average of 19 years.
Results
Of the 574 men in the study, 54 were diagnosed with Alzheimer's disease. Dr. Resnick and Dr. Moffat used physical, neurological and neuropsychological examinations to determine the presence of the disease. The study pointed out that while all men have decreasing levels in testosterone as they get older, men who developed Alzheimer's disease had a larger drop in testosterone. The authors hypothesize that testosterone protects the brain cells by limiting the build up of beta-amyloid proteins. When beta-amyloid proteins build up, they create the plaques that cause degradation in Alzheimer's disease, according to the Alzheimer's Disease Research website.
