Oral Health, Loneliness and Social Isolation. A Systematic Review and Meta-Analysis

Objectives Thus far, some empirical studies have investigated the association between oral health and loneliness as well as social isolation. However, a systematic review and meta-analysis is lacking synthesizing this evidence. Hence, our purpose was to close this knowledge gap. Design Systematic review and meta-analysis. Setting and Participants Observational studies examining the association between oral health and loneliness or social isolation were included. Disease-specific samples were excluded. Methods We searched three electronic databases (PubMed, PsycINFO, CINAHL), and did an additional hand search. Data extraction covered methods, sample characteristics and main findings. To evaluate study quality/risk of bias, the NIH tool was used. Study selection, data extraction and assessment of study quality were each conducted by two reviewers. Results Seven studies were included in our current work. Several cross-sectional studies and one longitudinal study reported an association between poorer oral health and higher loneliness as well as higher social isolation. The quality of the studies was mostly fair, with two studies of high quality. The pooled OR was 1.47 (95% CI 1.24-1.75) among the studies with adult samples. Conclusion Most of the included studies demonstrated an association between oral health and loneliness or social isolation. There is a lack of high quality studies on these associations; in particular, future studies should use longitudinal data to clarify the directionality between oral health and loneliness or social isolation. Prospero registration number CRD42021268116.