Disadvantaged childhood socioeconomic circumstances are associated with increased all-cause and cause-specific adult mortalityChildhood poverty and low education linked to higher adult mortality

BACKGROUND: Childhood socioeconomic circumstances are important determinants of adult health, yet no recent meta-analysis has quantified these associations or formally assessed evidence certainty. We aimed to synthesise evidence on associations between childhood socioeconomic circumstances and adult all-cause and cause-specific mortality. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, SocIndex, ASSIA, and ProQuest Public Health from inception to May 26, 2026, without language restrictions, supplemented by backward citation searching. We included cohort studies examining associations between childhood socioeconomic conditions (parental education and occupation, economic circumstances, housing and material conditions, and composite indicators) and adult mortality (age ≥18 years), reporting quantitative estimates with extractable data. No randomised controlled trials were identified; all included studies were observational longitudinal studies. Two reviewers independently screened records and extracted data. Risk of bias was assessed using ROBINS-E and evidence certainty using GRADE. We pooled hazard ratios (HRs) using random-effects meta-analysis with restricted maximum likelihood estimation and calculated the relative index of inequality (RII) to enable standardised comparisons across exposure definitions. This study is registered with PROSPERO (CRD42024594671). FINDINGS: Of 17 163 records screened, 102 studies (approximately 8·5 million participants across 24 countries) were included. Disadvantaged socioeconomic circumstances were associated with higher adult mortality across all exposure types, with harmful associations in 390 of 474 estimates (82%; 95% CI 79-86; p<0·0001). For father's occupation, the pooled HR for all-cause mortality was 1·26 (95% CI 1·18-1·35; I=90·1%; 18 studies), corresponding to 181 (95% CI 125-243) excess deaths per 100 000 population per year. Cause-specific analyses indicated elevated risks for cardiovascular (HR 1·26, 95% CI 1·13-1·42), respiratory (HR 1·70-1·85 across sex specific analyses), and lung cancer mortality (HR 1·52 in both sexes). The RII was highest for economic circumstances (RII 2·33, 95% CI 1·51-3·60) and parental education (RII 2·28, 1·60-3·26). Findings were consistent across exposure types, world regions, and risk of bias strata. 50 (49%) included studies were at high or very high risk of bias, primarily due to inadequate confounding control; sensitivity analyses restricted to lower risk of bias studies yielded consistent results. GRADE certainty ranged from very low to moderate. INTERPRETATION: Disadvantaged childhood socioeconomic circumstances are associated with increased adult mortality across diverse measures of disadvantage and causes of death, supporting prioritisation of early-life interventions to reduce long-term mortality inequalities. FUNDING: None.