TOOTH LOSS TRAJECTORIES AND THEIR ASSOCIATION WITH FUNCTIONAL DISABILITY AMONG OLDER CHINESE ADULTS: RESULTS FROM THE CHINESE LONGITUDINAL HEALTHY LONGEVITY SURVEY

Background Tooth loss becomes more prevalent with age and increases risk of functional dis-ability. However, the strength of tooth loss varies between individuals rather than a uniform loss with age. We aimed to evaluate tooth loss trajectories and their association with functional disability among older Chinese adults.Methods We included 16,209 participants aged >= 65 years from five waves of the Chinese Longitudinal Healthy Longevity Survey 2002-2014. The number of teeth, Activi-ties of Daily Living (ADL), and Instrumental ADL (IADL) were assessed at base-line and subsequently every three years. ADL disability and IADL disability were defined as needing any help in any item of the Katz scale and a modified Law-ton's scale, respectively. A group-based trajectory model was used to determine tooth loss trajectories based on the self-reported number of teeth and general-ized estimating equation models were used to explore associations of tooth loss trajectories with ADL disability and IADL disability.Results This study identified four tooth loss trajectories, including Progressively Mild Loss (14.4%), Progressively Severe Loss (21.5%), Persistently Severe Loss (45.1%), and Edentulism (19.0%) among older Chinese adults. Compared with the Pro-gressively Mild Loss trajectory, the Progressively Severe Loss (ADL disability: OR = 1.45, 95% CI: 1.15-1.84; IADL disability: OR = 1.71, 95% CI: 1.47-1.99), Per-sistently Severe Loss (ADL disability: OR = 2.33, 95% CI:1.93-2.82; IADL disability: OR = 3.29, 95% CI: 2.82-3.84) and Edentulism (ADL disability: OR = 3.25, 95% CI: 2.58-4.09; IADL disability: OR = 3.60, 95% CI: 2.93-4.42) trajectories were signifi-cantly associated with an increased risk of functional disability with adjustment for potential confounders.Conclusion Four distinct tooth loss trajectories were identified among older adults and those with severe tooth loss trajectories had an increased risk of functional disability than those with a mild loss trajectory.