Perceived chewing ability and need for long-term care in the elderly: a 5-year follow-up study.

Increasing need for long-term care in older adults is expected with the ageing of Japan's population. The aim of the present study was to show the relationship between perceived chewing ability and long-term care needs for over 5 years in elderly persons. The chewing ability of 812 elderly persons living independently was evaluated at baseline using self-assessed masticatory ability, and it was classified into one of three categories: ability to chew all foods (good masticatory ability), ability to chew only slightly hard food (fair masticatory ability), and ability to only chew soft or pureed food (poor masticatory ability). Participants' care needs were then followed through Japan's long-term care insurance system for over 5 years. The log-rank test and Cox proportional hazard model were used to examine statistical differences in the frequency of care-needs certification between participants with good and fair or poor masticatory ability. Among participants aged 65-79 years, the frequency of care-needs certification was significantly higher in those with fair or poor masticatory ability than in those with good masticatory ability, and the relative hazard ratio was significantly higher in those with fair or poor masticatory ability than in those with good masticatory ability, after adjusting for age, gender, current employment status, educational background, social interaction, chronic medical conditions and dentition status. These relationships were not found among those aged 80-93 years. Impairment in perceived chewing ability may be associated with higher incidence of certification in Japan's long-term care insurance system among elderly persons aged 65-79.