Relationship Between Swallowing Problems and Tooth Loss in Community-Dwelling Independent Elderly Adults: The Fujiwara-Kyo Study

OBJECTIVES: To investigate the relationship between swallowing problems and the number of remaining teeth in healthy elderly people. DESIGN: Cross-sectional. SETTING: Nara, Japan. PARTICIPANTS: Three thousand six hundred sixty-three male and female volunteers aged 65 and older who were living independently were analyzed. MEASUREMENTS: Swallowing problems were defined operationally using a questionnaire and the 30-mL water swallow test. Data were collected on the number of remaining teeth, maximum bite force, occlusal status, presence or absence of oral dryness, and medical history. RESULTS: The prevalence of swallowing problems was 15.1% (n = 554) in this population. A positive correlation was observed between the number of remaining teeth and maximum bite force. The number of remaining teeth was categorized according to tertiles. Multiple logistic regression analysis revealed that the adjusted odds ratios for 0 to 13 or 14 to 24 remaining teeth to 25 to 32 remaining teeth for swallowing problems were 2.04 (95% confidence interval (CI) = 1.60―2.60) and 1.31 (95% CI = 1.02― 1.70), respectively. Significant increases in these odds ratios were found in a trend test (P < .001). CONCLUSION: Tooth loss is associated with swallowing problems. Having fewer teeth inhibits masticatory ability, which disturbs the execution of smooth swallowing. Preventive measures against tooth loss at a younger age may be effective at reducing the risk of laryngeal penetration and aspiration at an older age.