The epidemiology of healthy ageing scores in mid-age and older adults from the Gambia, Zimbabwe and South Africa: a cross-sectional study

Background Healthy ageing is a global priority. We determined Healthy Ageing Scores [HAS] (lower scores indicate worse ageing), and associations with sociodemographic/lifestyle factors, chronic conditions, and health-related quality-of-life (HRQoL) across three African countries. Methods This population-based cross-sectional study recruited adults aged ≥40 years in five sites: rural Gambia (n = 1052) and urban Gambia (n = 1218); rural South Africa (SA) (n = 948) and urban SA (n = 968); and urban Zimbabwe (n = 1110). Researcher-administered questionnaires and physical assessments quantified 22 items to generate ‘Ageing Trajectories of Health-Longitudinal Opportunities and Synergies' Scores. Chronic conditions were defined by self-report, medications and assessments; EuroQol-5-Dimension-5-Level assessed HRQoL. Linear mixed models examined associations between HAS and sociodemographic/lifestyle factors, accounting for sampling design. Findings 5296 adults were mean [SD] age 61.0 [12.9] years; 53.3% female. Mean [SD] HAS was 45.4 [6.4], ranging from 44.1 [6.8] in rural SA to 48.4 [7.1] in urban Zimbabwe. Being 55–69 years-of-age (vs. 40–54) was associated with lower HAS (mean difference −2.21 [95%CI,−2.58; −1.84]), as was being ≥70 years (vs. 40–54) (−5.29 [−5.67; −4.91]), independent of sex and study site. Being female was associated with lower mean HAS (−2.45 [−2.76; −2.15]), as was being obese (−1.60 [−2.03; −1.17]), using tobacco (−0.49 [−0.90; −0.08]) and being less physically active (−0.62 [−1.03; −0.22]) after adjusting for study site, age, and sex. Mean HAS was lower with increasing number of chronic conditions: no chronic condition (47.0 [6.1]), two (44.9 [6.4]), and ≥4 conditions (42.6 [5.2]). HAS positively correlated with HRQoL utility scores (r = 0.607). Interpretation Being female, obese, physically inactive and using tobacco were associated with lower HAS. Multimorbidity was cumulatively associated with lower HAS. Context-focused interventions to promote healthy ageing in these higher-risk groups require evaluation. Funding National Institute for Health and Care Research (NIHR); NIHR-Wellcome Partnership for Global Health Research; Medical Research Council Musculoskeletal Functional Ability in Sub-Saharan Africa.