The Varied Clinical Presentations of Major Depressive Disorder

DSM-IV major depressive disorder (MDD) is a clinical syndrome notable for heterogeneity of its clinicalpresentation, genetics, neurobiology, clinical course, and treatment responsiveness. In an attempt to makesense of this heterogeneity, clinicians and researchers have proposed a number of MDD “subtypes” based ondifferences in characteristic symptoms (e.g., atypical, melancholic, psychotic), onset (e.g., early vs. late, postpartum,seasonal), course of illness (e.g., single vs. recurrent, chronic, double), and severity. This article providesa brief review of the status of several of the most common subtypes in terms of their clinical features,biological correlates, course of illness, and treatment implications.