Socioeconomic inequalities in prevalence and development of multimorbidity across adulthood: findings from the MRC 1946 National Survey of Health & Development

Abstract

AbstractObjectiveTo estimate multimorbidity trajectories and quantify socioeconomic inequalities based on both childhood and adulthood socioeconomic position in the risks and rates of adult multimorbidity accumulation.DesignProspective longitudinal national birth cohort study.MethodsParticipants from the 1946 National Survey of Health and Development (NSHD) who attended the age 36 assessment in 1982 and any one of the follow-up assessments at ages 43, 53, 63 & 69 (N=3,723, 51% males). Information on 18 health conditions was based on a combination of self-report, biomarkers, health records and prescribed medications. We estimated multimorbidity trajectories and delineated socioeconomic inequalities (based on childhood and adulthood social class and highest education) in multimorbidity at each age and in longitudinal trajectories.ResultsMultimorbidity increased with age from 0.7 conditions on average at 36 years to 3.7 at 69 years. Multimorbidity accumulation was non-linear, accelerating with age at the rate of 0.08 conditions/year (95% CI 0.07-0.09) at 36-43 years to 0.19 conditions/year (95% CI 0.18-0.20) at 63-69 years. At all ages, the most socio-economically disadvantaged had 1.2 to 1.4 times greater number of conditions on average compared to the most advantaged. The most socioeconomically disadvantaged by each socioeconomic indicator experienced an additional 0.39 conditions (childhood social class), 0.83 (adult social class) and 1.08 conditions (adult education) at age 69 years, independent of all other socioeconomic indicators. Adverse adulthood socioeconomic status was associated with more rapid accumulation of multimorbidity, resulting in 0.49 excess conditions in partly/unskilled compared to professional/intermediate individuals between 63-69 years. Disadvantaged childhood social class, independently of adult socio-economic position, was associated with accelerated multimorbidity trajectories from age 53 onwards.ConclusionsSocioeconomically disadvantaged individuals have both earlier onset and more rapid accumulation of multimorbidity resulting in widening inequalities into old age, with independent contributions from both childhood and adulthood socio-economic position.