The association between oral health and cardiovascular disease risk and the potential mediating role of depressive symptoms: evidence from the English longitudinal study of ageing

Existing studies on the association between oral health and Cardiovascular Disease (CVD) are predominantly cross-sectional. This study, based on longitudinal data, focuses on middle-aged and older adults to explore their relationship, examining depressive symptoms as a potential statistical mediator. Data were drawn from Waves 7 to 10 of the English Longitudinal Study of Ageing (ELSA), comprising individuals aged 50 years and older from England. Cox regression models were employed to examine the associations between self-reported baseline oral health, cumulative average oral health scores, and CVD. Changes in self-reported oral health status were categorized to reflect the patterns of “all good”, “all bad”, “worse”, and “better”. A logistic regression model was used to examine the association between changes in oral health status and the incidence of Cardiovascular Disease (CVD). Meanwhile, the number of attributable cases (AT) and the population attributable fraction (PAF) were calculated to quantify the burden of deteriorating oral health on CVD among middle-aged and older adults. Finally, the potential mediating role of depressive symptoms was assessed using the Bootstrap method. Over the 6-year follow-up period, 467 participants (12.21%) experienced the onset of cardiovascular disease (CVD). In fully adjusted models, compared to the “poor” group, the risk of CVD was lower in the “fair” group, though this did not reach statistical significance (HR = 0.772, 95% CI: 0.533–1.117, p = 0.169), and was significantly lower in the “good” (HR = 0.708, 95% CI:0.505–0.994, p = 0.046), “very good” (HR = 0.668, 95% CI:0.472–0.945, p = 0.023), and “excellent” (HR = 0.655, 95% CI:0.431–0.995, p = 0.047) groups. Higher cumulative average oral health scores were associated with increased CVD risk (HR = 1.138, 95% CI:1.045–1.240, p = 0.003). Over the follow-up period, participants who maintained good oral health across all assessments exhibited a notably lower likelihood of developing cardiovascular disease (CVD) compared with those who consistently reported poor oral health (OR = 0.690, 95% CI: 0.491–0.971, p = 0.033). Mediation analysis showed that the Centre for Epidemiological Studies Depression scale (CESD) score partially accounted for mediated the association between oral health exposure and cardiovascular disease, with a mediation proportion of 27% ( P < 0.001). Sensitivity analysis the robustness of these findings. Poor self-reported oral health is associated with an increased risk of cardiovascular disease, and better oral health is associated with a lower CVD burden. Depressive symptoms may partially mediate this association, although the observational design precludes causal inference.