Association between tooth loss and orodigestive cancer mortality in an 80-year-old community-dwelling Japanese population: a 12-year prospective study.

BACKGROUND: A growing body of evidence has indicated a possible association between oral and gastrointestinal (orodigestive) cancers and periodontal disease or tooth loss. However, the evidence remains contradictory. This study investigated whether tooth loss, which is indicative of poor oral health and a potential source of oral infections, is associated with death from orodigestive cancer. METHODS: The study included 656 subjects in Fukuoka prefecture, Japan, who were 80 years old at baseline in 1998. All subjects underwent oral clinical examination and answered a questionnaire to determine their background characteristics. Cause of death over the 12-year follow-up was recorded from the registers at the Public Health Centers and classified according to the WHO International Classification of Diseases. Statistical analysis of associations was performed using Kaplan-Meier and Cox multivariate regression analyses. RESULTS: A significant association was observed between tooth loss (continuous variable) and cancer death (hazard ratio (HR): 1.03, 95% confidence interval (CI): 1.00-1.07), after adjustment for potential confounders, including sex and smoking status. However, that association became insignificant in the fully adjusted model. On the other hand, tooth loss was significantly associated with orodigestive cancer (HR: 1.06, 95% CI: 1.01-1.13), even in the fully adjusted model including place of residence as a part of socioeconomic status. CONCLUSIONS: This study provides the first evidence in a prospective study in a Japanese population that tooth loss is associated with increased orodigestive cancer mortality, although the causality remains unclear.

Relationship between tooth loss and mortality in 80-year-old Japanese community-dwelling subjects.

BACKGROUND: Findings from several studies suggest associations between tooth loss and health outcomes, including malnutrition, poor quality of life, and mortality, in older individuals. However, limited information is available regarding whether those associations remain true in very elderly subjects after adequately considering confounding factors such as sex and smoking status. Herein, we determined whether the number of teeth in 80-year-old subjects is an independent predictor of mortality. METHODS: We initially contacted 1282 80-year-old community-dwelling individuals born in 1917, of whom 697 responded and participated in a baseline study, with follow-up examinations conducted 4 and 5.5 years later. Data from interviews and medical and oral examinations were obtained, and oral health was determined according to the number of teeth remaining in the oral cavity. RESULTS: A total of 108 and 157 subjects died in 4 years and 5.5 years, respectively, after the baseline study. Tooth loss was significantly associated with mortality at age 85.5, but not at age 84, after adjusting for potential confounders. When the analysis was stratified by sex, we found a stronger association in females in follow-up examinations conducted at both 4- and 5.5 years. On the other hand, the effect of tooth loss on mortality was not significantly different between smokers and non-smokers. CONCLUSION: Tooth loss is a significant predictor of mortality independent of health factors, socio-economic status, and lifestyle in octogenarians, with a stronger association in females.

Association of chewing ability with cardiovascular disease mortality in the 80-year-old Japanese population.

BACKGROUND: Few have studied the association between chewing ability and longevity. DESIGN AND METHODS: In this prospective study, we analyzed 697 80-year-old participants residing in Fukuoka Prefecture, Japan. Chewing ability was assessed on the basis of the types of food that each participant reported being able to chew. RESULTS: During follow-up, 108 participants died. Patients reporting the lowest numbers of chewable foods were associated with higher risks of cardiovascular mortality than those who were able to chew all the types of food surveyed (multivariate hazard ratio: 4.60; 95% confidence interval: 1.01-21.1). CONCLUSIONS: Impaired dentition status with poor masticatory ability was an independent risk factor for cardiovascular mortality in active elderly individuals.