Relationship between Metabolic Syndrome and Number of Teeth in Japan

The 2004 Japanese National Health and Nutrition Survey collected data on several measures, including self-reported dental health. In addition, this was the first nationwide survey to focus on metabolic syndrome (MetS) in Japan. Therefore, the authors used this nationwide data set to assess the relationship between number of teeth present and MetS. Anonymized data were available with permission from the Ministry of Health, Labour and Welfare of Japan. Data from 3,195 men and women aged 35 to 99 y were examined, and logistic regression analyses were used to evaluate the association between number of teeth and MetS. Moreover, the authors performed an analysis of covariance to compare the mean number of teeth between those with and those without MetS, after adjusting for confounders. In comparison with those having ≥28 teeth, those with fewer remaining teeth demonstrated significantly higher odds of having MetS. Specifically, those having 1 to 9 teeth had higher odds of having MetS than those with more teeth and were more than twice as likely to be affected than those with ≥28 teeth. Furthermore, individuals with MetS in the age groups of 45 to 54, 55 to 64, and 65 to 74 y had significantly fewer teeth than those without MetS in the same age groups. These results suggest that the number of teeth present is associated with the prevalence of MetS in the Japanese population. Knowledge Transfer Statement: The results of this study can be used by clinicians when they examine patients with periodontal disease or extensive tooth loss to refer for a general medical examination.