Association between cumulative social isolation risk factors and oral health-related quality of life among older adults: an analysis of wave 10 of the Korean Longitudinal Study of Ageing

Objectives: To examine the association between social isolation and oral health-related quality of life among older adults. Methods: This cross-sectional study analyzed data from 3,972 adults aged 65 years or older who participated in wave 10 of the Korean Longitudinal Study of Ageing. Social isolation was assessed using three factors: spousal status, living alone, and frequency of face-to-face contact with close persons. Participants with at least two risk factors were classified as socially isolated. Oral health-related quality of life was measured using the Geriatric Oral Health Assessment Index (GOHAI). Associations were examined using complex-sample multiple linear regression with cross-sectional sampling weights and sequential adjustment for sociodemographic, health-related, and oral health-related characteristics. Results: The GOHAI score was lower in the socially isolated group than in the non-isolated group (35.23 vs. 37.05, p<0.001). In the unadjusted model, social isolation was associated with a 1.818-point reduction in GOHAI score (p<0.001). The association remained statistically significant in the fully adjusted model (unstandardized coefficient [B] = −0.497; 95% confidence interval [CI], −0.983 to −0.011; p=0.045). Conclusions: Social isolation was associated with poorer oral health-related quality of life among older adults, even after accounting for relevant characteristics. Considering social relationships may help inform assessments of oral health-related quality of life and the planning of oral health programs for older adults.