Association of Tooth Loss With Development of Swallowing Problems in Community-Dwelling Independent Elderly Population: The Fujiwara-kyo Study

Background Tooth loss induces changes to the anatomy of the oral cavity. We hypothesized that tooth loss may disturb smooth swallowing in healthy elderly people. The purpose of this study was to investigate the effect of tooth loss on the development of swallowing problems in an independent elderly population. Methods This was a 5-year prospective cohort study conducted in Nara, Japan. Included in this analysis were 1,988 community residents aged 65 years or older without swallowing problems at baseline. The participants were classified into quartile groups according to the number of remaining teeth at the baseline survey: 0-12, 13-22, 23-26, and 27-32 teeth. A decrease in the number of teeth during the survey was calculated by subtracting follow-up number from baseline number. Main outcome was the development of swallowing problems at follow-up. Results During follow-up, 312 individuals developed swallowing problems. After adjustment for confounding factors by multiple logistic regression analysis, the odds ratios for developing swallowing problems in participants with 13-22 or 0-12 teeth were 2.42 (95% confidence interval [CI], 1.61-3.63) and 2.49 (95% CI, 1.68-3.69), respectively, compared to participants with 27-32 teeth, demonstrating a significant relationship. The odds ratio of per 1 tooth decrease over 5 years was 1.08 (95% CI, 1.02-1.13), showing a significant association. Conclusions Swallowing problems due to aging are more likely to develop in individuals with fewer teeth.