Lower socio-economic status in adolescence is associated with poor oral health at an older age: Mediation by social and behavioural factors

AimTo examine the mediators between lower socio-economic status (SES) in adolescence and oral health at an older age to uncover the underlying mechanisms of the association. MethodsParticipants (n = 21 536) aged >= 65 years from the Japan Gerontological Evaluation Study were evaluated. The dependent variables were self-rated chewing difficulty and having <= 19 remaining teeth. The main independent variable was self-perceived SES in adolescence. The Karlson-Holm-Breen method was used for mediation analysis. ResultsMean age of the participants was 74.8 years (standard deviation = 6.4), and 51.5% were female. Overall, 5598 (26.0%) participants reported chewing difficulty and 9404 (43.7%) had <= 19 remaining teeth. Lower SES in adolescence was associated with a higher prevalence of chewing difficulty (odds ratio [OR] = 1.38, 95%confidence interval [CI] = 1.29-1.48; total effect). After controlling for mediators, OR for lower SES in adolescence was 1.22 (95%CI = 1.13-1.30; direct effect) and 1.13 (95%CI = 1.11-1.16; indirect effect). Mediators, prominently the number of teeth and income, explained 39.3% of the associations. Lower SES in adolescence increased the odds of <= 19 remaining teeth by OR = 1.23 (95% CI = 1.16-1.31; total effect). After controlling for mediators, the OR for lower SES in adolescence was 1.03 (95%CI = 0.97-1.10; direct effect) and 1.19 (95%CI = 1.16-1.23; indirect effect). Mediators, prominently educational attainment, explained 85.0% of the associations. ConclusionsLower SES in adolescence was associated with poor oral health at an older age through mediators. Approaches that consider social determinants from the beginning of the life course are required.