Background: This study examined psychosocial functioning as a predictor of recovery from episodes of unipolar major depression.
Methods: 231 subjects diagnosed with major depressive disorder according to Research Diagnostic Criteria were prospectively followed for up to 20 years as part of the NIMH Collaborative Depression Study. The association between psychosocial functioning and recovery from episodes of unipolar major depression was analyzed with a mixed-effects logistic regression model which controlled for cumulative morbidity, defined as the amount of time ill with major depression during prospective follow-up. Recovery was defined as at least eight consecutive weeks with either no symptoms of major depression, or only one or two symptoms at a mild level of severity.
Results: In the mixed-effects model, a one standard deviation increase in psychosocial impairment was significantly associated with a 22% decrease in the likelihood of subsequent recovery from an episode of major depression (OR=0.78, 95% CI: 0.74-0.82, Z=-3.17, p<0.002). Also, a one standard deviation increase in cumulative morbidity was significantly associated with a 61% decrease in the probability of recovery (OR=0.3899, 95% CI: 0.3894-0.3903, Z=-7.21, p<0.001).
Limitations: The generalizability of the study is limited in so far as subjects were recruited as they sought treatment at academic medical centers. The analyses examined the relationship between psychosocial functioning and recovery from major depression, and did not include episodes of minor depression. Furthermore, this was an observational study and the investigators did not control treatment.
Conclusions: Assessment of psychosocial impairment may help identify patients less likely to recover from an episode of major depression.