Effects of a Community-Based Program for Oral Health and Nutrition on Cost-Effectiveness by Preventing Disability in Japanese Frail Elderly: A Quasi-Experimental Study Using Propensity Score Matching

Objective In the Japanese Long-Term Care Insurance (LTCI) system, a community-based program for oral health and nutrition (OHN program) has been implemented with the aim of reducing incident disability and care costs. However, the effectiveness of this program has not been confirmed epidemiologically. The purpose of the present study was to test the hypothesis that the OHN program does reduce incident disability and care costs. Design A prospective study with a 28-month follow-up period was conducted using data from administrative databases at Tagajo City, Japan. Among frail elderly persons (aged 65 years or more) who were enrolled in the LTCI program in Tagajo, 64 participants in the OHN program and 128 controls (nonparticipants) were selected by propensity score matching. Measurements We used 2 types of outcome measure: composite outcome (incident disability and death) and care cost. Data on incident disability were retrieved from the public LTCI database. Care cost was defined as the total amount of LTCI service cost added to medical care cost. Results The hazard ratio of composite outcome was significantly lower for the intervention group than for the control group (hazard ratio = 0.32, 95% confidence interval 0.12–0.82). Even when we set incident disability as an outcome, the hazard ratio for the intervention group did not change (hazard ratio = 0.33, 95% confidence interval 0.11–0.97). The mean cumulative care cost during the 28 months tended to be lower for the intervention group ($4893) than that for the control group ($5770), but this was not statistically significant by the gamma regression model (cost ratio = 0.85, P =.513). The mean care cost per unit follow-up period (1 month) for the intervention group was significantly lower (cost ratio = 0.54, P =.027). Conclusions The results of this study suggest that the OHN program is effective for preventing incident disability and, consequently, for saving care costs per unit survival period.