Social isolation, loneliness and the risk of Frailty status: a meta-analysis of observational studies.

Abstract

<h4>Background& objective</h4>This meta-analysis aims to evaluate the association between social isolation, loneliness and the risk of frailty across different populations.<h4>Search methods</h4>We conducted a systematic meta-analysis of cohort studies published from 2018 to 2025. A comprehensive search was performed across multiple databases, including PubMed, Embase, and the Cochrane Library, using relevant MeSH terms and keywords: "social isolation", "loneliness", "frailty" and "risk". Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random-effects models. Subgroup analyses were conducted based on study characteristics and population demographics. Heterogeneity was assessed using the I² statistic, and publication bias was evaluated through funnel plots.<h4>Results</h4>A total of 8 cohort studies, encompassing 78,769 participants, were included. The pooled OR for social isolation and frailty risk was 1.31 (95% CI: 1.16-1.48, I² = 95.1%, p < 0.001). Loneliness was associated with an increased risk of frailty (OR = 1.83, 95% CI: 1.76-1.89, I² = 43.4%, p < 0.001). Subgroup analyses revealed a significantly higher frailty risk in Asian populations (OR = 1.314, 95% CI: 1.115-1.549, p < 0.001), and females with a history of social isolation have a slightly higher risk of frail states than males.<h4>Conclusion</h4>Loneliness is a significant predictor of frailty risk, particularly in Asian populations. Early detection of loneliness may play a crucial role in frailty status prevention strategies.<h4>Clinical trial number</h4>Not Applicable. The present systematic review is registered in PROSPERO's International Prospective Register of Systematic Reviews (registration number CRD420251173118 dated 13th Feb 2025).