Abstract
Background: Hip fracture is a common geriatric condition associated with disability, institutionalization, and mortality. In-hospital mortality reflects both patient vulnerability and the quality of care, yet evidence from Latin America is scarce. Objective: We aimed to identify factors associated with in-hospital mortality in Chilean older adults with hip fractures. Methods: We conducted a retrospective cohort study using the Chilean National Health Fund (FONASA) database, which included patients aged 60 years or older who were hospitalized with a hip fracture (ICD-10 S72.0-S72.2) between 2019 and 2024. Variables analyzed included age, sex, surgical treatment, number of comorbidities, Diagnosis-Related Group (DRG) severity level, and relative weight. Survival was evaluated with Kaplan-Meier curves and log-rank tests. Multivariable Cox proportional hazards models estimated adjusted hazard ratios (HR) with 95% confidence intervals (CI). Results: The cohort comprised 40,253 patients (76.8% women; mean age 81.9 ± 9.1 years). Overall, in-hospital mortality was 3.5%. Independent predictors of mortality included absence of surgery (HR = 9.56; 95% CI: 8.38-10.90), higher DRG severity level (HR = 3.87; 95% CI: 3.42-4.37), advanced age (HR per year = 1.05; 95% CI: 1.04-1.05), male sex (HR = 1.12; 95% CI: 1.03-1.27), and multimorbidity (≥3 comorbidities; HR = 2.73; 95% CI: 1.98-3.99). Conclusions: Timely surgery and stratification with administrative indicators (DRG) are key to reducing in-hospital mortality. The findings support strengthening orthogeriatric models in Chile.