Life Course Socioeconomic Position and health in older adulthood age: A Formal Mediation Analysis in the 1958 British Birth Cohort

Summary Background Childhood socioeconomic position (SEP) is a key determinant of later-life health. Understanding the extent to which adult SEP mediates this association into early old age is important for explaining how health inequalities are propagated across generations and how they might be addressed in later life. To our knowledge, no prospective study has examined whether childhood SEP remains associated with health at the threshold of older age and the extent to which any such association is mediated by adult SEP. Methods We used data from the 1958 British Birth Cohort, a prospective study that has followed participants since birth, drawing on earlier data collected at birth and ages 33 and 55 years and newly collected data from the age 62 sweep. Using interventional causal mediation analyses, we assessed whether adult occupational class, education, housing tenure, and income mediate associations between childhood social class (manual vs non-manual) and health at age 62 (self-rated health, C-reactive protein [CRP], cholesterol ratio, Glycated hemoglobin [HbA1c], and N-terminal pro–B-type natriuretic peptide [NT-proBNP]). Findings Associations between childhood SEP and self-rated health, CRP, cholesterol ratio, and HbA1c persisted after accounting for adult SEP. Mediation was outcome-specific and differed by sex. Among men, occupational class mediated 39% of the association with self-rated health (indirect effect RR 0·90, 95% CI 0·86–0·95) and education mediated 27% (0·93, 0·90–0·96). Among women, education mediated 10% (0·95, 0·91–0·98) and housing tenure mediated 6% (0·97, 0·94–0·99). Indirect effects for CRP were smaller, and mediation was minimal for cholesterol ratio, HbA1c, and NT-proBNP Interpretation Population-level improvements in adult SEP could reduce, but are unlikely to eliminate, later-life health inequalities associated with childhood SEP. Reducing these inequalities will require policies that address disadvantage in early life and improve adult financial and employment conditions. Funding UK Economic and Social Research Council