Longitudinal association of dentition status with dietary intake in Japanese adults aged 75 to 80 years

Limited information is available on the temporal association between dentition status and dietary intake. The aim of this 5-year prospective cohort study was to investigate whether impaired dentition was associated with subsequent decline in dietary intake in older Japanese adults. Two hundred and eighty-six community-dwelling Japanese individuals, all aged 75 years at baseline, were included in the study. Functional tooth units (FTUs), defined as a pair of opposing natural or prosthetic teeth excluding third molars (range: 0-14), were counted on the basis of baseline dental examinations. Individuals with ≤5 FTUs were defined as having impaired dentition. Dietary intake was assessed at baseline and 5 years later, using a validated dietary questionnaire. Robust regression analyses were used to evaluate the differences in change in dietary intake between participants with and without impaired functional dentition, after adjustment for potential confounders. Sixty-one study participants (21·3 %) were defined as having impaired dentition. Overall, mean values for all estimated dietary variables (energy, nutrients and food groups) declined over time. Notably, individuals with impaired dentition demonstrated a significantly (P < 0·05) greater degree of decline in the intake of multiple nutrients (protein, sodium, potassium, calcium, vitamin A, vitamin E and dietary fibre) and food groups (vegetable and meat) than those without impaired dentition, after adjusting for potential confounders. The results of this study describe the temporal association of impaired dentition with the decline in selected nutrient and food group intake among older Japanese adults.