Family income and material deprivation: do they matter for sleep quality and quantity in early life? Evidence from a longitudinal study

INTRODUCTION: The aim of this article is to investigate the determinants of sleeping patterns in children up to age 9 on a large and geographically homogeneous sample of British children and parents, focusing in particular on the role of economic and social factors, specifically on income. AIMS AND METHODS: The data of this study come from the Avon Longitudinal Study of Parents and Children, a long-term health research project that recruited over 14000 pregnant women who were due to give birth between April 1991 and December 1992 in Bristol and its surrounding areas, including some of Somerset and Gloucestershire. Logistic regression models for the sleep problem dummies and log-linear models for the sleep quantity. RESULTS: One additional item in the material deprivation index is associated to an increase of around 10-20% in the odds of having at least 1 sleep problem. Similarly, children from the richest families are less likely to have any sleep problem up to 115 months (around 20% reduction in the odds). Mother's characteristics (i.e., education and mental health in the pregnancy period) are also significant predictors. Sleep quantity does not vary much and is not sensitive to socioeconomic factors. CONCLUSION: Exposure to income-related inequalities affects child sleep. Further research is needed to understand if sleep in early life influences future health and economic trajectories.