Citations 0
February 2, 2005

Dementia and Testosterone Levels in Men

Author Affiliations

Letters Section Editor: Robert M. Golub, MD, Senior Editor.

JAMA. 2005;293(5):551-552. doi:10.1001/jama.293.5.551-b

To the Editor: The study by Ms Rosario and colleagues1 shows a close association between Alzheimer disease (AD) and reproductive hormone levels. The finding that there were no differences in brain estrogen levels brings into question the long-standing hypothesis that men are less susceptible to AD because they continue to produce estrogen from androstenedione, a precursor of testosterone. While the sex steroids are undoubtedly important for brain function, they are controlled by a complex feedback loop that is made up of numerous other hormones including gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulating hormone, inhibins, activins, and follistatin. Since there is an inverse relationship between serum concentrations of sex steroids and gonadotropins, effects ascribed to declines in estrogen or testosterone could equally well be a consequence of higher levels of gonadotropins. We previously reported that individuals with AD have increased luteinizing hormone in neurons susceptible to AD pathology,2 consistent with the current finding of low brain testosterone.

First Page Preview View Large
First page PDF preview
First page PDF preview