Are serial dexamethasone suppression tests useful in electroconvulsive therapy?

In addition to its diagnostic utility, the dexamethasone suppression test (DST) may also have value as a predictor of recovery or relapse. Evidence for this has derived mainly from patients receiving antidepressants while some paradoxical findings have emerged for patients undergoing electroconvulsive therapy (ECT). To explore this we charted Hamilton rating scale scores and DST results during ECT for 30 patients who were nonsuppressors before ECT. While week-to-week severity measure corresponded roughly to DST changes in the expected fashion, shifts in test results had no apparent predictive value. In fact, changes to nonsuppressor status were more often followed by improvement than were changes to suppressor status. These findings suggest that ECT may have a number of opposing, direct and indirect effects on the hypothalamic-pituitary-adrenal axis.