Association Between Oral Health and Frailty in Older Korean Population: A Cross-Sectional Study

Frailty is closely associated with biological age, concurrent medical conditions, morbidity, and decreased survival. Poor oral health is common in older individuals and is associated with frailty. Considering its potential importance, a study on the association between oral health and frailty is meaningful. Therefore, we aimed to analyze the association between major oral health factors and frailty using nationally representative samples of older adults.

This cross-sectional study included 3018 older adults (age ≥ 65 years) from the seventh Korea National Health and Nutrition Examination Survey. Oral examination results, laboratory data, handgrip strength, life style factors derived from questionnaires, and food intake survey results were analyzed. This study used the deficit accumulation model among the main operational definitions of frailty. We constructed a frailty index based on 36 items and classified participants as non-frail, pre-frail, or frail. Oral health factors included chewing difficulty, number of teeth, periodontal disease, and number of carious teeth. Logistic regression analysis was performed to determine significant factors.

A total of 1222 (40.5%), 1014 (33.6%), and 782 (25.9%) individuals were classified as non-frail, pre-frail, and frail, respectively. Chewing difficulty was associated with increased risk of frailty after adjusting for age, sex, socioeconomic factors, and comorbidities (odds ratio 2.68, 95% confidence interval 2.08-3.44). Periodontal disease was positively associated with chewing difficulty (odds ratio 1.29, 95% confidence interval 1.07-1.56), and chewing difficulty decreased as the number of teeth increased (odds ratio 0.97, 95% confidence interval 0.96-0.99).

Chewing difficulty was significantly associated with frailty in the older population. Considering the negative effect of chewing difficulty on frailty, more attention should be focused on oral health.