The relationship between longitudinal declines in dehydroepiandrosterone sulfate concentrations and cognitive performance in older men

Background: The observation that dehydroepiandrosterone (DHEA) concentratio ns decrease markedly with age has led to the hypothesis that declining DHEA concentrations may contribute to age-related changes in cognition. In the United States, DHEA is widely available as an over-the-counter supplement t hat individuals are using in an effort to ameliorate age-related cognitive and physical changes. Objective: To investigate the relationship between age-associated decreases in endogenous DHEA sulfate (DHEA-S) concentrations and declines in neurops ychological performance in a prospective, longitudinal study. Methods: The subjects were 883 men from a community-dwelling volunteer samp le in the Baltimore Longitudinal Study of Aging. The men were aged 22 to 91 years at the initial visit, and they were followed up for as long as 31 ye ars (mean, 11.55 years), with biennial reassessments of multiple cognitive domains and contemporaneous measurement of serum DHEA-S concentrations. Out come measures were the results of cognitive tests of verbal and visual memo ry, 2 tests of mental status, phonemic and semantic word fluency tests, and measures of visuomotor scanning and attention. Serum DHEA-S concentrations were determined by standard radioimmunoassay. Results: Neither the rates of decline in mean DHEA-S concentrations nor the mean DHEA-S concentrations within individuals were related to cognitive st atus or cognitive decline. A comparison between the highest and lowest DHEA -S quartiles revealed no cognitive differences, despite the fact that these groups differed in endogenous DHEA-S concentration by more than a factor o f 4 for a mean duration of 12 years. Conclusion: Our longitudinal results augment those of previous prospective studies by suggesting that the decline in endogenous DHEA-S concentration i s independent of cognitive status and cognitive decline in healthy aging me n.