Background: Vulnerability as defined by high levels of neuroticism, low self-esteem, and poor coping skills characterizes individuals with a history of major depressive episodes (MDEs).
Objective: To separate postmorbid vulnerability into (1) trait effects (ie, the continuation of premorbid vulnerability); (2) state effects of subthreshold (residual) symptoms on personality or its perception; and/or (3) scar effects (ie, negative personality change that develops during an MDE and persists beyond MDE remission).
Methods: Data come from the Netherlands Mental Health Survey and Incidence Study, a prospective Dutch psychiatric population-based survey. We obtained psychiatric (Composite International Diagnostic Interview) and personality data on neuroticism, depressive coping style, self-esteem, and mastery from 4796 respondents at 3 time points (T1, T2, and T3), 12 and 24 months apart. Between- and within-subjects differences were tested with repeated-measures analysis of variance and adjusted for sex, age, and time.
Results: After T1, 409 respondents developed an MDE, of whom 334 were MDE-free at T3. In comparison with individuals without any lifetime MDE, the 262 subjects with a first MDE had higher premorbid T1 vulnerability scores on each personality measure (0.38-0.83 effect size units). During the MDE, vulnerability scores further increased (0.33-0.52 effect size units) but returned to premorbid levels after MDE remission. We found no scar effects among subgroups with severe or long-lasting MDEs. Subthreshold residual symptoms at T3 biased comparisons between T1 and T3 if the premorbid period of T1 to MDE onset was longer than the postmorbid period of MDE remission to T3, misleadingly suggesting scar effects. We obtained similar results in the 147 subjects with recurrent MDEs.
Conclusions: There was no evidence of a negative change from premorbid to postmorbid assessment for any of the personality traits. Postmorbid vulnerability reflected the continuation of premorbid vulnerability. Pre-post MDE comparisons are sensitive to prodromal and residual symptoms. Our findings suggest 2 independent simultaneous processes: (1) the ongoing expression of vulnerability as a personality deviance; and (2) synchrony of change between severity of depressive symptoms and personality deviance.