Oral function and cumulative long-term care costs among older Japanese adults: a prospective 6-year follow-up study of long care receipt data

OBJECTIVES: This study evaluated the relationship between status of oral function and related long-term care service costs. DESIGN: This was a prospective 6-year follow-up study of previous survey data. SETTING: The data were obtained from the Japan Gerontological Evaluation Study conducted between 2010 and 2011. PARTICIPANTS: The participants were functionally independent older adults in 12 municipalities across Japan. INTERVENTIONS: Care service benefit costs were tracked over 6 years using publicly available claims records (n=46 616) to monitor respondents’ cumulative care costs. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome variable was the cumulative cost of long-term care insurance services during the follow-up period. We adjusted for the presence or absence of oral function problems, age, sex, physical function and socioeconomic and lifestyle background at the time of the baseline survey. RESULTS: Tobit analysis revealed that, compared with those with no oral function problems, cumulative long-term care service benefit costs for those with one, two or three oral function problems were approximately US$4020, US$4775 and US$82 92, respectively, over 6 years. Compared with those with maintained oral function, there was a maximum difference of approximately US$8292 in long-term care service costs for those with oral function problems. With increase in number of oral function problems, there was a concomitant elevation in the cost of long-term care. CONCLUSIONS: Oral function in older people was associated with cumulative long-term care insurance costs. The oral function of older people should be maintained to reduce future accumulated long-term care insurance costs. Compared with those with maintained oral function, there was a maximum difference of approximately US$8292 in long-term care service costs for those with oral function problems. The cost of long-term care was amplified as oral problems increased.