Preeclampsia and the longitudinal risk of hospitalization for depression at 28 years

PURPOSE The association between pregnancy characteristics and risk of depression in women is poorly understood. We investigated the relationship between preeclampsia and risk of hospitalization for depression over three decades. METHODS We carried out a longitudinal cohort study of 1,210,963 women who delivered an infant in any hospital in Quebec, Canada, between 1989 and 2016. The exposure was preeclampsia at the first or in subsequent pregnancies, including preeclampsia onset time (early < 34 weeks vs. late ≥ 34 weeks of gestation) and severity (mild, severe, superimposed). The outcome was hospitalization for depression any time after pregnancy. We used Cox proportional hazards regression models adjusted for maternal characteristics to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of preeclampsia with depression hospitalization. RESULTS Women with preeclampsia had a higher incidence of hospitalization for depression compared with no preeclampsia (1.43 vs. 1.14 per 1000 person-years). Preeclampsia was associated with 1.16 times the risk of depression hospitalization after 28 years of follow-up (95% CI 1.09-1.23). Associations were present for mild (HR 1.15, 95% CI 1.07-1.24), severe (HR 1.16, 95% CI 1.04-1.29) and late onset preeclampsia (HR 1.17, 95% CI 1.10-1.25). Risks were more pronounced after the first year postpartum. CONCLUSION Preeclampsia appears to be associated with the risk of depression hospitalization several decades after pregnancy. Clinicians who care for women with mental health disorders should be aware that a history of preeclampsia increases the risk of severe depression.