DHEAS Levels Linked to Cognitive Function in Women
NEW YORK (Reuters Health) Mar 13 - The results of a study conducted in Australia and published in the March issue of the Journal of Clinical Endocrinology and Metabolism suggest that higher circulating levels of dehydroepiandrosterone sulfate (DHEAS) are associated with better cognitive function in
"There are data that suggest that DHEA and DHEAS may have neuroprotective effects and that the decline in the production of these steroids with healthy aging may contribute to neuronal dysfunction and degeneration, and thus cognitive decline," Dr. Susan Davis and colleagues from Monash University, Prahran, Victoria, write. However, evidence that higher levels of endogenous DHEA and DHEAS are associated with better cognitive function is lacking.
The researchers examined the association between levels of DHEAS, a circulating storage form of DHEA and a "robust" measure of DHEA production, and cognitive function in 295 women (mean age, 55 years). The women were recruited into the community-based, cross-sectional study between September 2003 and December 2004. Women with any conditions that might adversely affect cognitive function were excluded.
Dr. Davis and colleagues found that women with higher circulating levels of DHEAS performed better on executive function tests. A positive association was also observed between circulating DHEAS and higher scores on tests of simple concentration and working memory in women with more than 12 years of education.
No association was found between circulating DHEAS levels and performance on tests of verbal and non-verbal learning and retention or focused attention.
Favorable independent associations were also identified between cognitive performance and activities such as living with other people, doing crosswords, and playing a musical instrument.
"Possible explanations for our findings include direct actions of DHEA/DHEAS via a putative DHEA receptor, via the androgen receptor, or as neurosteroids and endogenous ligands for sigma-1 receptors," Dr. Davis' team suggests. DHEAS may also be a "marker of overall potential for tissue intracrine androgen and estrogen production in women but not the actual mediator of the effect."
"Alternatively, DHEAS may be simply a marker of general good health," they note.
The researchers stress that they found no evidence that taking DHEA supplements, commonly sold over the counter in the US but not available in Australia, had any effect on cognitive performance.
Although the clinical implications of these findings are unclear, Dr. Davis' group suggests the results "provide a strong basis for future studies designed to test the cause-and-effect nature of the relationship between serum levels of DHEAS and cognitive function in women."
J Clin Endocrinol Metab 2008;93:801-808.