Supplementary file 1_Long-term dental care utilization trajectories as behavioral markers of cognitive aging: a 14-year national cohort study.docx

Compared with Persistent High, both suboptimal trajectories showed faster cognitive decline (Decreasing: β = −0.085 per 2-year wave, 95% CI − 0.118 to −0.053; Persistent Low: β = −0.107, 95% CI − 0.133 to −0.081; both p < 0.0001), corresponding to approximately 0.60 and 0.75 additional points of decline over 14 years, respectively, against a 2.29-point decline in the Persistent High group. The difference between the Persistent Low and Decreasing trajectories was not significant (β difference = −0.0217, 95% CI − 0.0580 to 0.0146; p = 0.241).

Worsening ADL limitations accounted for 9.3 and 11.6% of the associations for the Decreasing and Persistent Low trajectories, respectively. In a lagged analysis separating exposure and mediator assessment (2006–2016) from outcome assessment (2016–2020), the direct associations and ADL-mediated pathway remained significant, whereas the SRH-to-cognition pathway did not.</p>Conclusion<p>Persistently low and declining dental care utilization were associated with similarly faster cognitive decline, with functional deterioration representing the principal mediating pathway.

Long-term dental care utilization may be an accessible behavioral marker of broader functional vulnerability. Although modest, these associations may have public health relevance because utilization can be captured through surveys and administrative or claims data. Causal inference cannot be established from this observational study.</p>