The impact of interpersonal racism on oral health related quality of life among Indigenous South Australians: a cross-sectional study

BACKGROUND: Interpersonal racism has had a profound impact on Indigenous populations globally, manifesting as negative experiences and discrimination at an individual, institutional and systemic level. Interpersonal racism has been shown to negatively influence a range of health outcomes but has received limited attention in the context of oral health. The aim of this paper was to examine the effects of experiences of interpersonal racism on oral health-related quality of life (OHRQoL) among Indigenous South Australians. METHODS: Data were sourced from a large convenience sample of Indigenous South Australian adults between February 2018 and January 2019. Questionnaires were used to collect data on sociodemographic characteristics, cultural values, utilization of dental services, and other related factors. OHRQoL was captured using the Oral Health Impact Profile (OHIP-14) questionnaire. We defined the dependent variable 'poor OHRQoL' as the presence of one or more OHIP-14 items rated as ‘very often’ or ‘fairly often'. Experiences of racism were recorded using the Measure of Indigenous Racism Experiences instrument. Interpersonal racism was classified into two categories (‘no racism’ vs ‘any racism in ≥ 1 setting’) and three categories ('no racism', 'low racism' (experienced in 1–3 settings), and 'high racism' (experienced in 4–9 settings)). Logistic regression was used to examine associations between interpersonal racism, covariates and OHRQoL, adjusting for potential confounding related to socioeconomic factors and access to dental services. RESULTS: Data were available from 885 participants (88.7% of the total cohort). Overall, 52.1% reported experiencing any interpersonal racism in the previous 12 months, approximately one-third (31.6%) were classified as experiencing low racism, and one-fifth (20.5%) experienced high racism. Poor OHRQoL was reported by half the participants (50.2%). Relative to no experiences of racism in the previous 12 months, those who experienced any racism (≥ 1 setting) were significantly more likely to report poor OHRQoL (Odds Ratio (OR): 1.43; 95% Confidence Interval (CI): 1.08–1.92), after adjusting for age, education level, possession of an income-tested health care card, car ownership, self-reported oral health status, timing of and reason for last dental visit, not going to a dentist because of cost, and having no family support. This was particularly seen among females, where, relative to males, the odds of having poor OHRQoL among females experiencing racism were 1.74 times higher (95% CI: 1.07–2.81). CONCLUSION: Our findings indicate that the experience of interpersonal racism has a negative impact on OHRQoL among Indigenous Australians. The association persisted after adjusting for potential confounding factors. Identifying this link adds weight to the importance of addressing OHRQoL among South Australian’s Indigenous population by implementing culturally-sensitive strategies to address interpersonal racism.