Association Between Number of Missing Teeth and Hyperlipidemia: The TCLSIH Cohort Study

Background: To explore the association between the number of missing teeth and the prevalence of hyperlipidemia in a Chinese adult population. Methods: 13,932 adults were investigated in the TCLSIH cohort study. The number of missing teeth was determined at baseline through a self-reported questionnaire, and then classified into three categories: 0, 1-2, and >= 3. We defined hyperlipidemia as total cholesterol (TC) >= 5.17 mmol/L or triglycerides (TG) >= 1.7 mmol/L or low-density lipoprotein (LDL) cholesterol >= 3.37 mmol/L or a self-report of physician-diagnosed hyperlipidemia during follow-up visits. Cox proportional-hazards regression models were employed to assess the relationship between the number of missing teeth and incident hyperlipidemia. Results: A total of 6756 first-incident cases of hyperlipidemia occurred during 42,048 person-years of follow-up (median follow-up, 4.2 years). After adjusted confounders, multivariable HRs and 95% CI for incident of hyperlipidemia across the categories of missing teeth were as follows: in male participants, 1.00 (reference), 1.10 (0.98, 1.22), and 1.03 (0.91, 1.16) (P for trend = 0.30); in female participants, 1.00 (reference), 1.09 (0.99, 1.19), and 1.18 (1.04, 1.33) (P for trend < 0.01). Conclusion: The number of missing teeth is associated with an increased risk of hyperlipidemia in female participants but not in male participants. Systemic chronic inflammation may potentially mediate this association.