Understanding social inequalities in childhood hospital admissions: longitudinal analysis of the UK Millennium Cohort Study

Abstract

BackgroundChildhood hospital admission rates are increasing annually and are socially patterned. To inform policies to reduce hospital admissions in children, we aimed to assess risk factors for hospital admissions and the extent to which any socioeconomic inequality in admissions could be attenuated after accounting for risk factors. MethodsThis analysis used a sample of 11 085 children, across five sweeps from ages 9 months to 11 years, from the UK Millennium Cohort Study. The Millennium Cohort Study oversamples children living in disadvantaged areas and ethnic minority groups by means of a stratified clustered sampling design, and includes sampling weights to address attrition. The primary outcome for the present analysis was parental report of a child “ever being admitted to a hospital ward” (ever admitted) by age 11 years. Parents' educational attainment at the child's birth was the main exposure. Primary outcome data were analysed with Poisson regression, according to parental education, adjusted for covariates including perinatal risk factors, maternal and child health status, and environmental risk factors. Findings4615 parents (45·6%) reported that their child had been admitted to hospital by age 11 years. Children of parents with no educational qualifications were more likely than those of parents with degree level or higher qualifications to have been admitted (risk ratio 1·49, 95% CI 1·20–1·85), and there was evidence of a dose-response association. Controlling for risk factors attenuated the increased risk of admissions in children from households with the lowest educational attainment (adjusted risk ratio 1·09, 95% CI 0·93–1·29). In the fully adjusted analysis, low birthweight (1·24, 1·06–1·45) and longstanding illnesses (1·21, 1·18–1·24) were associated with an increased risk of being ever admitted, and female sex was protective (0·81, 0·75–0·88). Repeating the analysis with the main exposure as income produced similar results. InterpretationIn a contemporary representative sample of children in the UK, nearly half were admitted to hospital by age 11 years. Children of parents with no qualifications had around 50% greater risk of admission, largely explained by differences in childhood longstanding illness and low birthweight. Policies to reduce inequalities in these factors might also reduce inequalities in hospital admissions. Study limitations include the potential for differential self-reporting of hospital admission from households with different educational attainment, and not being able to explore service model differences. FundingNone.