The role of disadvantaged childhood conditions on cognitive function and disability in late life: findings from a Swedish longitudinal study

OBJECTIVES: We aimed to investigate whether disadvantaged childhood conditions are associated with decreased cognitive function or disability in late life (sensitive period hypothesis). We also assessed whether this putative association is mediated by chronic disease or chronic pain in adult life (chain of risks hypothesis). METHODS: = 508 at baseline). Data were merged with the Swedish Level of Living Survey, and a composite score representing childhood conditions was created for each participant. We used ordinary least squares regression and generalized estimating equations to examine whether childhood conditions were cross-sectionally/longitudinally associated with decreased cognitive function (Mini-Mental State Examination, MMSE) or disability (ADL/iADL) in late life. Gender differences were also assessed. The role of the number of diseases or chronic pain level in adult life in the association under investigation was tested using mediation analysis. RESULTS: Adjusting for potential confounders, we found that disadvantaged childhood conditions were associated with lower MMSE scores at baseline (β = -0.14[-0.27,-0.02]), but not in terms of change over time (β = -0.01[-0.03, 0.01]), for both male and female participants. Mediation analysis indicated that the number of diseases or chronic pain level accounted for only a minimal part of the association, suggesting a limited indirect effect. No correlation was found with ADL/iADL. CONCLUSION: Findings indicate that disadvantaged childhood conditions are associated with decreased cognitive function, but not disability, in late life. Our results support the sensitive period hypothesis.