Association between perinatal depressive symptoms and suicidal risk among low-income South African women: a longitudinal study

Purpose The aim of this study was to assess the association between depressive symptoms and suicidal risk over time among perinatal women at risk for depression antenatally, and assess modifying effects of age, perinatal stage and depressive symptom trajectory. Methods A total of 384 adult pregnant women were recruited from two antenatal clinics in an informal settlement near Cape Town, South Africa, and followed up at eight months gestation, and at 3- and 12-month postpartum. The MINI 6.0 Suicidality module and the Hamilton Depression Rating Scale (HDRS) were used to measure suicidal risk and depression, respectively. Generalised Estimating Equations were used to assess the association between change in depressive symptoms from one assessment to the next (predictor) and change in suicide score or change in suicidal risk (score >= 9) (outcomes). Results HDRS scores were positively correlated with suicide score (95% CI 0.35, 0.78; p<0.001), and with odds of being at moderate risk for suicide, after controlling for risk of suicide at the previous assessment (adjusted odds ratio=1.15; 95% CI 1.09, 1.22; p<0.001). Age was a significant effect modifier: change in HDRS scores was not associated with change in suicide scores among participants aged 35-45 years. Secondary analyses indicated that a decrease in HDRS score was associated with a decrease in suicide scores, but an increase in HDRS score was not associated with change in suicide score. Conclusions Depression and suicide are overlapping but relatively independent phenomena, especially among older or more chronically depressed perinatal women.