Determinants of One-Year Mortality After Hip Fracture in U.S. Older Adults: A Socio-Ecological Systematic Review and Meta-Analysis

Abstract Background Hip fracture remains a leading cause of morbidity and mortality among older adults in the United States. The aim of this systematic and meta-analytical review is to synthesize available evidence on predictors of one-year mortality following hip fracture among older adults, guided by a socio-ecological framework. Methods We searched PubMed, Embase, Web of Science, CINAHL, and Scopus for U.S.-based studies published between 2010 and 2025 reporting one-year mortality after hip fracture. Studies were included if they evaluated predictors of mortality across pre-injury, perioperative, or post-discharge phases. Data were extracted on study design, population characteristics, mortality outcomes, and risk factors. Predictors examined in ≥3 studies were pooled using random-effects meta-analysis, and narrative synthesis was conducted for predictors with limited data. Methodological quality was assessed using the Joanna Briggs Institute checklist. Results Twenty-eight studies (n = 835,226) met inclusion criteria. Pooled one-year mortality was 21.8%, ranging from 7.1% to 54.4%. Advancing age and male sex were consistent non-modifiable risk factors. Comorbidity burden, including congestive heart failure, chronic kidney disease, myocardial infarction, and dementia, and measures of frailty and functional impairment were among the strongest predictors, often doubling mortality odds. Perioperative factors such as higher injury severity and delayed surgery, and post-discharge factors including hospital readmission, missed follow-up visits, and postoperative complications, were also associated with increased mortality. Conclusion One-year hip fracture-related mortality remains high and stems from multifactorial causes. A multi-level, systems-oriented approach may be necessary to meaningfully reduce long-term mortality in this growing and vulnerable population.