Dentition status and risk of frailty in older Chinese people: a 16-year prospective cohort study

Objective: To explore associations of dentition status with frailty and death. Methods: Based on the "Chinese Longitudinal Healthy Longevity Survey (CLHLS) in 2002-2018", a prospective cohort study was conducted that 21,159 participants not frail and aged >= 65 were included at baseline. The outcome was frailty and death. Frailty index (FI) was constructed based on 44 health items. The mediation role of high sensitivity C-reactive protein (hs-CRP) was examined using cross-sectional data in 2008, 2011 and 2014. Results: The incidence density of frailty was 50.1 (95%CI: 48.8-51.4) per 1,000 person-years. Compared with >= 20 natural teeth, the odds of frailty hazards were 1.27 (95%CI: 1.16-1.39) times higher for < 20 natural teeth with dental prostheses, and were 1.24 (95%CI: 1.14-1.35) times higher for < 20 natural teeth without dental prostheses; the odds of death hazards for < 20 natural teeth without dental prostheses were 1.36 (95%CI: 1.26-1.45) times higher. Among participants with <20 natural teeth and without dental prostheses at baseline, the odds of frailty hazards for using dental prostheses were 0.48 (95%CI: 0.41-0.56) times as high as those remaining not to use, and the odds of death hazards were 0.44 (95%CI: 0.39-0.48) times as high. The crosssectional data showed higher levels of hs-CRP explained 5-6% of associations between dentition status and frailty. Conclusion: Natural teeth <20 was associated with higher odds of frailty and death. Mediation analysis based on cross-sectional data offered clues for chronic inflammation pathway, yet this finding is still needed to be further verified.