Obesity and dental caries in childhood: trends in prevalence and socioeconomic inequalities - a multicohort population-wide data linkage study

Objectives To quantify levels of coexisting obesity and caries experience in children in Scotland, and any associated socioeconomic inequalities over the years 2011/2012–2017/2018.

Design A multicohort population-wide data linkage study.

Setting Local authority primary schools in Scotland.

Patients 335 361 primary 1 (approximately 5 years old) schoolchildren in Scotland between 2011/2012 and 2017/2018.

Main outcome measures Prevalence and inequalities in coexisting caries and obesity.

Results The prevalence of coexisting obesity and caries experience was 3.4% (n=11 494 of 335 361) and did not change over the 7 years. Children living in the 20% most deprived areas had more than sixfold greater odds of coexisting obesity and caries experience than children from the 20% least deprived areas (adjusted OR=6.63 (95% CI=6.16 to 7.14; p<0.001)). There was a large persistent socioeconomic gradient across the Scottish Index of Multiple Deprivation groups, with the Slope and Relative Indices of Inequality remaining unchanged over the 7 cohort years.

Conclusions Despite improvements in oral health in children in Scotland, the prevalence of coexisting obesity and caries experience has remained static, with large persistent inequalities. These conditions are likely to signal increased risk of chronic conditions including multimorbidity in adulthood and therefore early identification of children most at risk and timely intervention tackling common risk factors should be developed and evaluated.