The moderating effect of oral health on the association between exercise and frailty in patients with musculoskeletal disorders: Findings from the Korean Longitudinal Study of Aging

Abstract

Purpose: This study aimed to examine the effects of exercise and oral health on frailty and to investigate the moderating effect of oral health on the relationship between exercise and frailty among patients with musculoskeletal disorders. Methods: This descriptive, cross-sectional study used data from the seventh wave of the Korean Longitudinal Study of Aging. Frailty index based on 41 deficits across seven domains was used, and oral health was assessed using the Geriatric Oral Health Assessment Index. Hierarchical regression analysis was performed to confirm the moderating effect of oral health, and PROCESS macro model 1 by Hayes was applied to examine an inference test of the conditional effect of the moderator. Results: Data on 1,812 participants with musculoskeletal disorders (mean age 75.0 ± 8.6 years) was analyzed. Compared with no exercise, regular exercise (β= -2.39, 95% confidence interval [CI]= -3.42; -1.34) was significantly associated with lower frailty level. Good oral health (β= -0.38, 95% CI= -0.44, -0.32) was significantly associated with lower frailty level. A significant moderating effect of oral health on the relationship between regular exercise and frailty was detected (β= 0.18, 95% CI= 0.05, 0.30). Conclusions: The beneficial effects of regular exercise on frailty were greater in participants with poor oral health than in those with good oral health. Healthcare providers should actively encourage older patients with musculoskeletal disorders and poor oral health to exercise regularly. Combined exercise and oral healthcare interventions may be the most effective strategy for managing frailty in older patients with musculoskeletal disorders.