Prefectural Differences in Chewing Ability in Questionnaire for Specific Health Checkup and Exploring Related Factors

Abstract

 A new item named “chewing ability” was added to the Japanese specific health checkup questionnaire in 2018. Although the Ministry of Health, Labour and Welfare has released chewing ability data by prefecture, there have been no reports on the factors influencing regional differences. The purpose of this study was to examine prefectural differences in self-reported chewing ability and related socio-demographic factors for men and women aged 40–59 years. Those who selected “Sometimes it is difficult to chew due to dental problems” or “I can hardly chew” on the questionnaire were considered to have chewing difficulty. Regional differences in chewing difficulty were observed across sex and age groups. For example, among women aged 40–44 years, chewing difficulty varied from 7.1 to 14.0%, reveling that chewing difficulty rates differed by about two times among prefectures. Once these differences were identified, we investigated socio-demographic factors associated with chewing difficulty using publicly available government data for each prefecture. For men, greater chewing difficulty was associated with the divorce rate; the decayed, missing, and filled teeth (DMFT) index among 12-year-olds; and heart disease death rates, whereas university enrollment was associated with lower chewing difficulty. Among women, the divorce rate and caries prevalence in 18-month- and 3-year-olds were associated with higher rates of chewing difficulty, whereas university enrollment, number of secondary industry workers, and number of general clinics were associated with lower rates of chewing difficulty. These findings suggest that socio-economic factors and dental caries experience in children may influence self-reported chewing difficulty at the community level. Based on the results of this ecological study, it is necessary to further investigate this relationship through individual-level research.