Classification and treatment of sub-threshold depression.

PURPOSE OF REVIEW: The purpose of this review is to evaluate the recent literature on depressive spectrum disorders. RECENT
FINDINGS: Research into so-called 'minor' forms of depression has moved beyond efforts justifying these entities and describing their components to an exploration of the impact of depressive spectrum disorders on health, quality of life, and as a predisposing factor for major depressive disorder. As with major depression, pharmacological and psychosocial interventions may be useful treatments. Researchers have begun to examine the nature of depressive spectrum disorders in specific populations, such as the elderly and the medically ill.
SUMMARY: Sub-threshold forms of depression are becoming a focus of research at a time when quality of life and prevention of serious mental illness are being recognized as important public health concerns. Individuals with depressive spectrum disorders are at an increased risk of developing major depressive disorder and are more likely to have a history of episodes of depression. The challenges confronting psychiatric researchers include developing a consensus about diagnosis of depressive spectrum disorders and ways to measure their severity, and increasing public recognition of the impact of the entire spectrum of depression in order to facilitate the discovery of appropriate treatments.