A single DEX/CRH test in male drug-free depressed patients is associated with the clinical response to treatment with fluoxetine

Objectives: The DEX/CRH test has been proposed to be suitable as a biomarker for the prediction of treatment response in depression. Methods: We performed the DEX/CRH test in 10 severely depressed male patients with melancholic features before initiation of antidepressant treatment with 20 mg fluoxetine. Results: We found a low cortisol response (as measured by cortisol AUC) to a single DEX/CRH test to be associated with clinical response to treatment. Conclusions: A strength of this study lies in the inclusion of patients after a drug wash-out phase. Despite a certain inconsistency described in the literature, several studies support the notion that it might be of importance to measure baseline HPA system activity before choice of treatment. Further systematic studies are warranted.