902Effect modification by homeownership in the relationship between household income and child oral health

Abstract

Abstract Background Poor oral health among children is socially patterned and poorly understood. To optimise interventions aimed at reducing the persistent socioeconomic gap in health, we need to understand its shaping mechanisms. We examined if homeownership modifies the widely recognised association between household income and child oral health. Methods Data were analysed on 3,344 children from the Longitudinal Study of Australian Children. Multivariable regression models tested associations between tertiles of household income and dental decay and tooth loss. Effect modification by homeownership was tested on both additive and multiplicative scales. Models were adjusted for demographic variables, area of residence and family characteristics. Results For dental decay and tooth loss, children in households in the lower tertiles of income had worse oral health than children in the highest. Additive interaction was weakly supported in our models. The relative effect of income on oral health was greater for homeowners than renters for dental decay (medium household income 0.65 (95%CI: 0.44; 0.98) and low household income 0.82 (95%CI: 0.58; 1.15)) and tooth loss (medium household income 0.25 (95%CI: 0.09; 0.68) and low household income 0.41 (95%CI: 0.17; 0.97)). Conclusions Low-income children have poorer oral health outcomes. Although children of homeowners have better oral health than children of renters, income inequality is higher among the homeowner’s group. Current rent assistance programs for low-income families in Australia may minimise income-related inequalities on a relative scale. Key messages Our findings shed light on the potential of equalising policies in reducing income-related oral health inequalities.