Tooth loss, swallowing dysfunction and mortality in Japanese older adults receiving home care services

Severe tooth loss and swallowing dysfunction occur more frequently in dependent older adult populations. Poor oral health and functional status are expected to have a negative impact on general health. We examined whether mortality is related to the number of teeth and swallowing function in dependent older Japanese individuals receiving home care services.

Older adults aged ≥65 years who were receiving home care were included. The planned follow-up period was 3 years. Baseline data on the number of teeth, swallowing function, nutritional status, cognitive ability and activities of daily living were collected.

A total of 259 participants (mean age 85.0 ± 7.7 years) were enrolled. The mean length of follow up was 26.2 months. Severe tooth loss (≤9 present teeth) and swallowing dysfunction were observed in 68.0% and 32.0% of the participants, respectively. Cox's proportional hazards regression model showed that participants with both ≤9 teeth and swallowing dysfunction were at a higher risk of mortality compared with those with both ≥10 teeth and normal swallowing function (hazard ratio 2.89, 95% confidence interval 1.22-6.83). A significant interaction among severe tooth loss, swallowing dysfunction and mortality risk was observed.

Severe tooth loss and swallowing dysfunction were associated with increased mortality. The present study suggests that the maintenance of oral health and swallowing function has a positive effect on general health. Therefore, attention should be given to both tooth loss and swallowing function in dependent older adult populations. Geriatr Gerontol Int 2018; 18: 873-880.