Socioeconomic Position and Oral Health: Social gradients in oral health among adults in Scotland: Evidence from the Scottish Health Survey 2021

Abstract

Background: Socioeconomic inequalities in oral health are a persistent public health issue in the UK. Lower socioeconomic position is associated with poorer oral health outcomes, but the evidence for Scottish adults is limited. The pathways through which different dimensions of SEP, such as income, education, and social class, independently relate to oral health, and the extent to which behaviours explain these relationships, are not fully understood.

Aim: The aim was to assess the associations between three SEP indicators (household income, education, and social class) and oral health outcomes (functional dentition, dental pain, and oral health-related impact on quality of life) in Scottish adults. The research also aimed to assess whether oral health related behaviours (brushing, dental attendance, and smoking) partly explained these relationships.

Methods: This study conducted a secondary analysis of cross-sectional data from the Scottish Health Survey 2021. The analysis sample size was 2,161 adults aged 16 and over. The three binary outcome measures were having fewer than 20 teeth, reporting dental pain, and reporting at least one oral health-related impact on quality of life. Self-reported data on household income, educational qualifications, and social class were the main explanatory variables. A series of binary logistic regression models was constructed to assess the relationships, with initial models adjusted for age and sex, and subsequent models also adjusted for behavioural factors.

Results: Using age and sex adjusted models, socioeconomic gradients were observed across all outcomes. The poorest income quintile had over 4 times the odds of having fewer than 20 teeth compared to the richest (OR: 4.40, 95% CI 2.60-7.47). Similarly, adults with no qualifications had almost 5 times the odds compared to those with a degree or higher (OR: 4.96, 95% CI 2.87-8.55). For dental pain, routine/manual workers had twice the odds compared to managerial/professional workers (OR: 2.02, 95% CI 1.43-2.85). After controlling for behavioural factors, these associations attenuated but remained significant. For example, the odds of having fewer than 20 teeth for the poorest vs. the richest income group reduced but were still high (OR: 3.65, 95% CI 2.09-6.38). In mutually adjusted models, education showed an association with having fewer than 20 teeth, income for OHRQoL, and income and social class for dental pain. Further adjustment for behaviours only slightly altered these effects.

Conclusions: In this nationally representative sample of Scottish adults, all three SEP indicators were independently associated with poorer oral health outcomes in a graded fashion. The increased odds of adverse oral health in lower SEP groups could not be fully accounted for by behavioural factors. Further research is needed to explore other mediating pathways. These findings suggest that policies must address fundamental socioeconomic determinants in addition to promoting healthy behaviours to reduce oral health inequalities.