Risk factors for mortality in elderly patients with hip fractures: a meta-analysis of 18 studies

Background Hip fracture is common and associated with poor outcomes in elderly patients. This meta-analysis aims to investigate the risk factors that might increase the mortality rate in elderly patients with hip fracture. Methods PubMed, Embase, and Web of Science were systematically searched for observational studies regarding the prognostic factors of mortality in elderly patients with hip fracture. A fixed-effects or random-effects model was used to calculate pooled hazard ratio (HR) and 95% confidence intervals (95% CIs). Results Eighteen cohort studies, involving 223,875 patients, were included in this meta-analysis. The most prominent factors associated with mortality were higher age (HR 1.51, 95% CI 1.37, 1.67; P < 0.001), male gender (HR 1.91, 95% CI 1.67, 2.19; P < 0.001), cognitive impairment (HR 2.06, 95% CI 1.25, 3.40; P = 0.005), delirium (HR 2.14, 95% CI 1.50, 3.05; P < 0.001), dementia (HR 2.72, 95% CI 1.41, 5.26; P = 0.003), depression (HR 1.71, 95% CI 1.43, 2.05; P < 0.001), living with caregiver (HR 1.61, 95% CI 1.43, 1.82; P < 0.001), cardiovascular disease (HR 2.10, 95% CI 1.14, 3.86; P = 0.018), renal disease (HR 1.66, 95% CI 1.52, 1.82; P < 0.001), and malignancy (HR 1.75, 95% CI 1.30, 2.37; P = 0.031), whereas respiratory disease (HR 1.49, 95% CI 0.99, 2.24; P = 0.056), diabetes (HR 1.15, 95% CI 0.96, 1.37; P = 0.121), and smoking (HR 1.54, 95% CI 0.64, 3.71; P = 0.337) did not increase the risk of mortality. Conclusion The current study investigated several factors that might increase the risk of mortality in elderly patients with hip fracture. Further studies are needed to evaluate the effectiveness of specific interventions to reduce the risk of mortality.