The mediating role of social capital in socioeconomic inequalities of oral health behaviours among Brazilian older adults

Objectives Knowledge of the possible pathways linking socioeconomic status (SES) to oral health-related behaviours can improve the understanding of inequalities in oral health. Therefore, in this study, it was investigated whether social capital mediates the relationship between SES and oral health behaviours. Methods Through a cross-sectional study, data were analysed from participants aged >= 60 years from the Brazilian National Health Survey 2019 (n = 21 575). Structural equation modelling was used to test the direct and indirect pathways from a latent variable for SES to a latent variable for oral health behaviours: daily flossing, toothbrushing frequency and the use of dental care services. Results The maximum likelihood estimator was used for complex samples with robust standard errors, and the final model demonstrated an adequate fit. The findings demonstrated that a higher SES was directly associated with better oral health-related behaviours (standardized coefficient [SC]: 0.82; [90% CI: 0.78-0.85]) and indirectly via structural social capital (SC: 0.05; [90% CI: 0.02-0.07]). The total effect of SES on oral health-related behaviours was (SC: 0.87, [90% CI: 0.85-0.89]). Conclusion The findings demonstrate that structural social capital in older Brazilian adults might partly mediate the pathways to socioeconomic inequalities in oral health behaviours. However, there is a direct effect on oral health behaviours, reinforcing the hypothesis that SES is associated with oral health, based on paths that link income inequality to oral health.