Purpose: The present study analysed the association between anaemia and dental caries in adolescents on the basis of predisposing factors and presence of severely decayed teeth.
Materials and Methods: This observational study included a complex probabilistic sample of adolescents (17–18 years old) enrolled at public schools in São Luís, Brazil (n = 363). Two hypothesis models were tested: (1) anaemia and dental caries are associated given that they share predisposing factors, such as socioeconomic and high sugar consumption, and (2) the presence of severely decayed teeth may increase the susceptibility of patients to anaemia. In the first model, the association between anaemia and the history of dental caries (the outcome number of affected teeth) was analysed by Poisson regression. In the second model, the association between the presence of severely decayed teeth with pulp exposure/necrosis and the outcome anaemia was analysed by logistic regression. Bivariate and multivariate analyses after adjusting for socioeconomic factors and sugar consumption were performed, considering 5% of statistical significance level and using STATA 115.0.
Results: Anaemia was associated with a higher number of affected teeth with a history of dental caries in bivariate (means ratio [MR]: 1.30; 95% confidence intervals [CI95%]: 1.10–1.52; p = 0.001) and multivariate (MR: 1.18; CI95%: 1.01–1.39; p = 0.046) analyses. Severely decayed teeth with pulp exposure/necrosis were associated with anaemia in bivariate (odds ratios [OR]: 5.75; CI95%: 1.97–16.8; p = 0.001)] and multivariate (OR 5.51; CI95%: 1.71–17.74; p = 0.004) analyses.
Conclusion: This study suggests that anaemia and dental caries are associated in a population-based sample of adolescents and that predisposing factors and severely decayed teeth seem to be involved in this association.