SINGLE EPISODE OF MAJOR DEPRESSIVE DISORDER 1ST EPISODE OF RECURRENT MOOD DISORDER OR DISTINCT SUBTYPE OF LATE-ONSET DEPRESSION

Of 687 consecutive inpatients and outpatients with primary major depre ssive illness, 213 (31%) were categorized as single episode (SE) by DS M-III-R criteria. Systematic evaluation of familial, sociodemographic, temperamental and symptomatological characteristics permitted the nea rly equal division of SE into two categories: a. early-onset (< 45 yea rs) ''first episode'' superimposed on either depressive or hyperthymic temperaments (against a bipolar and unipolar familial background), mo re severe depression, higher rates of suicide attempts, greater anxiet y-somatization and psychotic tendencies, and with the potential for re currence; b. late-onset (greater-than-or-equal-to 45 years) isolated e pisode (against an unipolar familial background) with greater life str essors, pursuing a protracted course with less likelihood of recurrenc e. In most other respects, early-onset SE was intermediate between rec urrent major depression and late-onset SE. The implications of these f indings for the now largely abandoned category of ''involutional melan cholia'' are discussed.