Trends In Income-Related Inequalities in Oral Health in Ontario, Canada

Objectives: Oral health inequalities impose a substantial burden on society and the health care system across Canadian provinces. Monitoring these inequalities is crucial for informing public health policy and action towards reducing inequalities, however trends within Canada have not been explored. The objectives of this study are: (i) To assess trends in income-related inequalities in oral health in Ontario, Canada’s most populous province, over time; and (ii) to determine if the magnitude of such inequalities differ by age and sex.
Methods: Data representative of the Ontario population aged 12 years and older was sourced from the Canadian Community Health Survey cycles 2003 (n = 36,182), 2007/08 (n = 36,430), and 2013/14 (n = 41,258). Income-related inequalities in poor self-reported oral health (SROH) were measured using the Slope Index of Inequality (SII) and Relative Index of Inequality (RII) and compared across surveys. All analyses were sample-weighted and performed with STATA 15.
Results: The prevalence of poor SROH was stable over time, ranging from 14.1% to 14.8% between 2003 and 2013/14. SII estimates did not change (SII = 0.19), while variation in RII estimates was observed over time (2003 = 3.85; 2007/08 = 4.56; 2013/14 = 4.21); differences were not statistically significant. SII and RII gradually increased with age among 12 to 64-year olds. RII was slightly higher among females in all survey years.
Conclusions: Absolute and relative income-related inequalities in SROH have persisted in Ontario over time and are potentially more severe among females and middle-aged adults. Therefore, oral health inequalities in Ontario require attention from key stakeholders, including governments, regulators, and health professionals.