Associations of social isolation and loneliness with healthcare utilization among older adults: a systematic review and meta-analysis.

Background and Objectives: Social isolation and loneliness are significant public health concerns associated with increased healthcare utilization among older adults. This review aims to synthesize evidence on the associations between social isolation, loneliness, and healthcare utilization. Research Design and Methods: Five databases were searched from inception to March 21, 2025, using keyword groups related to social isolation/loneliness, older adults, and healthcare utilization (primary care, emergency visits, inpatient care, and outpatient care). Methodological quality was assessed using the Newcastle-Ottawa Scale. Random-effects models were employed to pool effect sizes (incidence rate ratios [IRRs], odds ratios [ORs]). Results: A total of 44 studies were included in the systematic review, and 34 were included in the meta-analysis (N = 309,023). Due to insufficient data, meta-analyses for the association between social isolation and primary care or outpatient care utilization were not conducted. Social isolation was statistically associated with increased inpatient care utilization (IRRs = 1.37, 95% CI: 1.24-1.53) but not with emergency department visits. For loneliness, meta-analyses for outpatient care were not feasible due to limited studies. Loneliness was statistically associated with increased emergency department visits (IRRs = 1.15, 95% CI: 1.06-1.24) and inpatient care utilization (OR = 1.13, 95% CI: 1.07-1.20) but not with primary care use. Discussion and Implications: This is the first meta-analysis to comprehensively synthesize the associations between social isolation, loneliness, and 4 types of healthcare utilization among older adults. The findings highlight the importance of addressing social isolation and loneliness as potential strategies to reduce avoidable healthcare utilization.