Longitudinal Associations of Loneliness with Mental and Physical Health in Ageing Adults in South Africa

Objectives: Few studies have investigated longitudinal associations of loneliness with health outcomes in Africa. This study aimed to assess the longitudinal associations between loneliness and mental and physical health among aging adults in South Africa. Methods: Data from the 7-year longitudinal Health and Ageing in Africa (HAALSI) study conducted in South Africa were used in the analysis (analytic sample: n = 3707, aged 40 years and older). Loneliness was measured with one question. Longitudinal relationships between loneliness and each health outcome were estimated using Generalized Estimating Equations analysis (GEE), hazard ratios (HRs) (95% CI) were used to determine the relationship between loneliness and 7-year mortality in the entire sample, and correlations between incident health outcomes and loneliness were evaluated using logistic regressions. Results: The prevalence of loneliness was 12.1% in 2015, 16.9% in 2019, and 16.3% in 2022. Multivariable analysis showed that loneliness was positively associated with the prevalence and/or incidence of four poor mental health indicators (e.g., poor sleep quality,AOR = 1.53, 95% CI: 1.30–1.80), four physical ill-health indicators (e.g., incident kidney disease, AOR = 2.50, 95% CI: 1.41–4.42), mortality (Hazard Ratio = 1.20, 95% CI = 1.04–1.39), and three poor behavioral health indicators (e.g., current tobacco use, AOR = 1.21, 95% CI = 1.04–1.42). Conclusion: The study discovered that several outcomes related to mental, physical, and behavioral health were associated with loneliness. Enhancing the detection and management of loneliness could lower mental and physical illness in aging adults in South Africa.