Sleep duration and incident and persistent depressive symptoms among a rural ageing population in South Africa

Abstract

BackgroundThe aim of the study was to assess the relationship between sleep duration and incident depressive symptoms (IDS) and persistent depressive symptoms (PDS) using longitudinal data from South Africa. MethodsThis longitudinal community study enrolled 3891 adults (≥40 years) from the “Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI)”. Sleep duration was assessed by self-report at wave 1, and depressive symptoms were assessed using the Center for Epidemiological Studies Depression Scale at wave 1 and 2. Outcomes were incident and persistent depressive symptoms at wave 2. Multivariable logistic regression analysis was conducted to assess the associations between sleep duration at wave 1 and incident, and persistent depressive symptoms. ResultsThe prevalence of IDS was 25.6% and PDS 30.8%. The prevalence of very short, short, normal, and long sleep duration at baseline was 3.6%, 10.1%, 60.9% and 25.4%, respectively. In the fully adjusted model, long sleep duration was positively associated with IDS among men (AOR: 1.37, 95% CI: 1.02–1.84), but not among women (AOR: 0.91, 95% CI: 0.67–1.23). No models among both men and women showed a significant association between short sleep and IDS. Long sleep duration was associated with PDS (AOR: 2.04, 95% CI: 1.20–3.48) among men but not among women (AOR: 1.26, 95% CI: 0.76–2.11). Short sleep showed among both sexes no significant associations with PDS. ConclusionLong but not short sleep duration was independently associated with IDS and PDS among men but not among women.