Association of Psychotic Experiences and Incident Depression in a Longitudinal Population-Based Community Survey.

Objective: The present study aims to determine if psychotic experiences in a general population sample are a risk factor for depressive disorders at a 15-year follow-up visit.

Method: A longitudinal population cohort of adults over age 18 from East Baltimore were followed from 1981 to 1996 with 1409 participants included in analyses. Delusions and hallucinations and depressive disorders were assessed using DSM-III criteria. Odds ratios were obtained using logistic regression with psychotic experiences modeled both dichotomously and as count variables as predictors of major and minor depressive disorders at wave three. Age, race, and sex were included as covariates in the model.

Results: Both delusions and hallucinations were associated with an increased odds of incident depressive disorders. Delusions, but not hallucinations, were associated with increased odds of major depressive disorder (adjusted odds ratio, 3.04 [95% CI = 1.29-7.13]) and both delusions and hallucinations were associated with increased odds of minor depressive disorder (adjusted odds ratios, 4.6 [95% CI = 2.11-10.04] and 3.93 [95% CI = 2.11-7.32]). There was a dose-response relationship in number of psychotic experiences reported and odds of depressive disorders.

Conclusions: Lifetime psychotic experiences, particularly delusions, in the absence of mental disorders, are associated with later depressive disorders. Results persist in a dose-response manner. Future research should determine whether transitory versus persistent psychotic experiences have a differential effect on later depression.