In 1985, I predicted (copyrighted) that DHEA would be low in
Alzheimer's disease and depression, and that it is the cause. The
first report of low DHEA in AD was in 1989. I just found the
following report that further supports my hypotheses.
Wolkowitz OM, et al., "Dehydroepiandrosterone (DHEA) treatment of
depression," Biol Psychiatry 41 (3): 311-318 (1997)
"Dehydroepiandrosterone (DHEA) and its sulfate, DHEA-S, are plentiful
adrenal steroid hormones that decrease with aging and may have
significant neuropsychiatric effects. In this study, six middle-aged
and elderly patients with major depression and low basal plasma DHEA
and/or DHEA-S levels were openly administered DHEA (30-90 mg/d x 4
weeks) in doses sufficient to achieve circulating plasma levels
observed in younger healthy individuals. Depression ratings, as well
as aspects of memory performance significantly improved. One
treatment-resistant patient received extended treatment with DHEA for
6 months: her depression ratings improved 48-72% and her semantic
memory performance improved 63%. These measures returned to baseline
after treatment ended. In both studies, improvements in depression
ratings and memory performance were directly related to increases in
plasma levels of DHEA and DHEA-S and to increases in their ratios with
plasma cortisol levels. These preliminary data suggest DHEA may have
antidepressant and promemory effects and should encourage double-blind
trials in depressed patients."