Exploring the Relationship between Social Isolation, Oral Health, and Cognitive Function in Elderly Residents of Guangxi: A Cross-Sectional Study

Background: Social isolation is a state of active or passive detachment from society that accelerates the decline of physical and mental functions of the elderly and leads to various adverse consequences. However, the relationship between social isolation and oral health as well as cognitive function has not yet been established. Methods: This was a cross-sectional survey conducted on an older population, where we collected data from 530 older adults using the General Information Questionnaire, LSNS-6, OHAT, and MoCA-B. The purpose of the survey was to investigate the current status of social isolation and its influencing factors, as well as to explore the relationship between oral health, cognitive function, and social isolation among the elderly. Results: In Guangxi, the incidence of social isolation among the elderly was 10.38%, with the high risk of social isolation accounting for 53.77%. Marital status, place of residence (urban or rural), cognitive function, and oral health status were identified as factors influencing social isolation among the elderly. The study found a negative correlation between the oral health score and social isolation score (r = -0.373, P < 0.001), with unhealthy oral status showing the strongest correlation with social isolation (r = -0.448, P < 0.001). Additionally, cognitive function scores were positively correlated with social isolation scores (r = 0.377, P < 0.001), with dementia showing the strongest association with social isolation (r = 0.324, P < 0.001). Furthermore, oral health demonstrated a high screening capacity for social isolation (AUC 95% CI = 0.823 (0.757, 0.890)), with an optimal cut-off value of 9.5, sensitivity of 67.3%, specificity of 90.1%, and Yoden index of 0.574. Conclusion: The social isolation status of the elderly is influenced by various factors, including marital status, residence (urban or rural), cognitive function, and oral health status. Moreover, the Oral Health Assessment Tool (OHAT) can be utilized as an effective objective tool for screening social isolation among the elderly.