Background: The relationship between frailty/pre-frailty, and multimorbidity in the elderly is recognized, but specific prevalence among community-dwelling elderly with multimorbidity is unclear. This study aims to determine these rates, analyze subgroup, and identify sources of heterogeneity to bolster evidence-based interventions and health policies.

Methods: We searched nine databases from inception to November 16, 2023, for cross-sectional and cohort studies on community-dwelling elderly with multimorbidity. Data were extracted to calculate the prevalence of frailty and pre-frailty. Study quality was assessed using AHRQ and NOS tools.

Results: Fifteen studies encompassing 9,683 participants with multimorbidity were analyzed. The pooled prevalence of frailty and pre-frailty was 18.1 % and 48.9 %, respectively. Age-stratified analyses found 17 % frailty and 58.4 % pre-frailty in the 70-74 age group, and 16.7 % and 54.2 % in those above 75 years. Cross-sectional studies showed 18.8 % frailty and 48.1 % pre-frailty, while cohort studies showed 18.1 % and 50.5 %, respectively. Asia had higher rates (22.7 % frailty, 43.5 % pre-frailty) than the Americas (9.9 % frailty, 56.3 % pre-frailty). By sample size, frailty prevalence was 21.3 % (<500), 9.1 % (500-999), and 17.9 % (≥1000), with pre-frailty at 51.1 %, 45.6 %, and 47.7 %. The FP method yielded higher prevalence estimates (17.7 % frailty, 51.6 % pre-frailty) than the FS method (9.5 % frailty, 39.2 % pre-frailty).

Conclusion: This study provides insights into the prevalence of frailty and pre-frailty among community-dwelling elderly with multimorbidity. Variations in prevalence rates may be attributed to differences in sample size and measurement tools, which also contribute to heterogeneity observed across subgroups.