Prevalence and factors associated with short and long sleep duration among community-dwelling persons 40 years and older: longitudinal evidence from rural South Africa, 2015-2022

Abstract

BACKGROUND: The prevalence and associated factors of short and long sleep duration in people 40 years of age and older have not been examined in longitudinal research in Africa. The purpose of this study was to use 3-wave longitudinal data from South Africa to determine these factors and prevalence, also stratified by sex. METHODS: We used information from three waves (2015-2022) of the "Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI)". Only individuals 40 years of age and older who were residents of the community and had complete measurements of sleep duration and anthropometry were included in the sample (analytic sample: n = 10483 observations). Self-reported sleep duration was assessed according to the American National Sleep Foundation: Short sleep: <7 h; long sleep: >9 h for ages 40-64, > 8 h for ≥ 65. Multinomial logistic fixed effects (FE) regressions were used to estimate the longitudinal associations between independent variables and short and long sleep duration (with normal or recommended sleep duration as reference). RESULTS: The prevalence of short sleep duration was 25.1% and long sleep duration 32.4%. FE logistic regressions showed that decreasing age, being employed, having depressive symptoms, having hypertension, poor sleep quality in men and decreased pain interference in women were associated with short sleep duration. Furthermore, an increase in age, a decrease in employment, a decrease in grandparental care, a decrease in fruit and vegetable intake, a decrease in cognitive functioning, having depressive symptoms, having dynapenia, and having dynapenic abdominal obesity were associated with an increase in long sleep duration. CONCLUSIONS: Our knowledge of the factors that contribute to short and long sleep duration in adults 40 years of age and older is improved by this long-term study.