Edentulism as an independent risk factor for sarcopenia: evidence from cross-sectional and longitudinal analyses based on the CHARLS cohort

Abstract

Background: Edentulism and sarcopenia are two highly prevalent, age-related conditions that share common nutritional, inflammatory, and functional pathways. Whether tooth loss independently contributes to the development of sarcopenia—and in which population strata this effect is strongest—remains uncertain, especially in Asian cohorts. Methods: We analysed 17,099 participants (baseline 2011) from the China Health and Retirement Longitudinal Study (CHARLS). Sarcopenia was defined by Asian Working Group for Sarcopenia 2019 criteria. Multivariable logistic models were fitted for cross-sectional analysis (wave 1). For longitudinal analysis (waves 1–3, seven-year follow-up), Cox proportional hazards models were fitted as the primary analysis, with logistic regression models applied as supplementary sensitivity analyses. Models were fitted sequentially: Model 1 (crude), Model 2 (plus demographic covariates), Model 3 (plus metabolic/inflammatory factors). Results were reported as odds ratios (OR) and hazard ratios (HR) with 95% confidence intervals (CI). Propensity-score matching (PSM) was applied to minimise selection bias. Subgroup analyses covered sex, residence, marital status, education, smoking, drinking, and region. Sensitivity analyses tested robustness. Results: Edentulism prevalence was 8.8%; sarcopenia prevalence, 15.0%. Cross-sectionally, edentulism increased sarcopenia risk in Model 1 (OR = 3.89, 95%CI: 3.46–4.37, P < 0.001) and remained significant after full adjustment (OR = 1.31, 95%CI: 1.04–1.66, P = 0.023). In the PSM set, the effect strengthened (Model 3: OR = 1.57, 95%CI: 1.15–2.14, P = 0.004). Longitudinally, Cox analyses showed edentulism predicted incident sarcopenia in PSM data (Model 3: HR = 1.21, 95%CI: 1.05–1.40, P = 0.008). Supplementary logistic regression analyses in the PSM set yielded consistent findings (Model 3: OR = 1.047, 95%CI: 1.009–1.086, P = 0.014). Subgroup analyses showed consistently higher risks in males, rural residents, low-education groups, non-smokers, non-drinkers, and western regions. Conclusions: Edentulism is a robust, independent marker of elevated sarcopenia risk in Chinese adults, with particularly strong effects in socio-economically vulnerable subgroups. Routine oral-health screening should be integrated into geriatric assessments to identify patients at high risk for sarcopenia.