Background: Dehydroepiandrosterone (DHEA) and its sulfate derivative DHEAS are neuroactive steroids. In the brain, they interact with gamma-aminobutyric acid (GABA(A)) receptors, which are involved in the regulation of anxiety and mood. The relevance of circulatory neurosteroids to psychiatric disorders and biological treatment is unknown.
Methods: Basal plasma levels of cortisol, DHEA, and DHEAS and the DHEAS-DHEA ratio were determined in 17 psychiatric inpatients before and after six electroconvulsive (ECT) therapy sessions, and all changes were statistically analyzed. For baseline values, 25 healthy individuals served as control subjects. Severity of depression and psychosis in the patients was measured with the Hamilton Depression Rating Scale (HDRS) and the Brief Psychiatric Rating Scale, respectively.
Results: Both basal and post-ECT levels of cortisol, DHEA, and DHEAS were significantly higher in the patients than in the control subjects. DHEAS levels in responding patients were higher at completion of treatment than at baseline. Patients defined as ECT nonresponders (change in HDRS < 30% from before treatments) exhibited elevated basal DHEAS levels compared with ECT responders.
Conclusions: Markedly elevated basal DHEAS levels (mean + 2 SD of control value) are associated with resistance to ECT and may serve as a potential predictive marker of nonresponsiveness to ECT in depressed patients.