Concurrent Diabetes Mellitus and Periodontitis in U.S. Adults: Mortality Associations and Machine Learning Risk Prediction

Abstract

Background/Objectives: We examined mortality associations by diabetes mellitus (DM)–periodontitis status and the incremental predictive value of composite inflammatory indices among adults with concurrent disease. Methods: We analyzed 10,632 adults from the National Health and Nutrition Examination Survey 2009–2014 linked to mortality data through 2019. Groups included neither DM nor periodontitis (NDM + NP), periodontitis alone (P), DM alone (DM), or concurrent DM and periodontitis (DM + P). Survey-weighted Cox and Fine–Gray models assessed all-cause and cardiovascular mortality. Among 978 participants with DM + P, nine survival models underwent five repeats of fivefold cross-validation to assess 5-year all-cause mortality prediction and the incremental value of eight composite inflammatory indices. Results: DM + P was associated with higher all-cause mortality than NDM + NP (HR, 1.51; 95% CI, 1.17–1.94) and P (HR, 1.31; 95% CI, 1.09–1.57). For cardiovascular mortality, DM + P was associated with higher mortality than NDM + NP (subdistribution hazard ratio [sHR], 1.51; 95% CI, 1.003–2.276), although the confidence interval only narrowly excluded 1.0. DM + P also had higher cardiovascular mortality than P (sHR, 1.55; 95% CI, 1.14–2.10). Neither outcome differed significantly between DM + P and DM. The Combined extreme gradient boosting Cox model had a concordance index and 5-year AUC of 0.754. Adding inflammatory indices did not significantly improve discrimination, prediction error, calibration, or net benefit. Observed 5-year mortality across predicted-risk tertiles was 3.7%, 7.4%, and 21.2%. Conclusions: Concurrent diabetes and periodontitis were associated with higher all-cause and cardiovascular mortality than periodontitis alone, but not with significantly higher mortality than diabetes alone. Composite inflammatory indices did not significantly improve prediction beyond clinical predictors.

The authors' abstract, as published at the source. Journal of Clinical Medicine, 2026 · DOI ↗