Why Recurrent Depression Should Be Reconceptualized and Redefined

Major depressive disorder is the leading cause of physical and mental disability worldwide, affecting more than 264 million people. A disproportionate amount of the enormous personal, societal, and economic toll is attributable to recurrent depression, wherein individuals suffer episodes repeatedly throughout their lives. At present, no clinical or scientific evidence can predict who will develop the disorder on an individual basis. We suggest two explanations for this pivotal prognostic impasse. First, a widespread belief that major depression is primarily a highly recurrent disorder is incorrect and misleading. Second, this incorrect belief has biased concepts, definitions, and research practices, further reinforcing the idea that depression usually is highly recurrent. We explain how such a belief and associated research practices stand in the way of progress, and we outline an agenda for discovering who is at greatest risk for recurrences following depression's first onset.