EFFECTS OF DEHYDROEPIANDROSTERONE REPLACEMENT IN ELDERLY MEN ON EVENT-RELATED POTENTIALS, MEMORY, AND WELL-BEING

Background, In humans, concentrations of the adrenal steroid hormone d ehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS) decline wit h age. Results from studies in rodents have suggested that DHEA admini stration can improve memory performance as well as neuronal plasticity . However, a first study from our laboratory could not demonstrate ben eficial effects of DHEA substitution on cognitive performance and well -being in elderly subjects. To further evaluate whether DHEA replaceme nt has effects on the central nervous system, an experiment using even t-related potentials (ERPs) was conducted. Methods, In this placebo-co ntrolled crossover study, 17 elderly men (mean age, 71.1 +/- 1.7 yr; r ange 59-81 yr) took placebo or DHEA (50 mg/day) for 2 weeks (double bl ind). After each treatment period subjects participated in an auditory oddball paradigm with three oddball blocks. In the first two blocks s ubjects had to count the rare tone silently, whereas, in the third blo ck they had to press a button. In addition, memory tests assessing vis ual, spatial, and semantic memory as well as questionnaires on psychol ogical and physical well-being were presented. Results. Baseline DHEAS levels were lower compared with young adults. After 2-week DHEA repla cement, DHEAS levels rose 5-fold to levels observed in young men. DHEA substitution modulated the P3 component of the ERPs, which reflects i nformation updating iii short-term memory. P3 amplitude was increased after DHEA administration, and only selectively in the second oddball block. DHEA did not influence P3 latency. Moreover, DHEA did not enhan ce memory or mood. Conclusions. A 2-week DHEA replacement in elderly m en results in changes in electrophysiological indices of central nervo us system stimulus processing if the task is performed repeatedly. How ever, these effects do not appear to be strong enough to improve memor y or mood.