The impact of frailty evaluation on the risk of venous thromboembolism in patients with hip fracture following surgery: a meta-analysis

Background Frailty has been associated with a higher incidence of overall postoperative complications and mortality. However, the influence of frailty on the risk of venous thromboembolism (VTE) in patients with hip fracture following surgery remains unclear. We performed a meta-analysis to systematically evaluate the above association.Methods PubMed, Embase, Cochrane Library, Wanfang and CNKI were searched for relevant observational studies comparing the incidence of postoperative VTE in patients of hip fracture with and without frailty. Data collection, literature searching, and statistical analysis were conducted independently by two authors. Using a heterogeneity-incorporating random-effects model, the results were pooled.Results In this meta-analysis, 9509 patients from nine cohort studies were included. Pooled results showed that compared to those without frailty, patients with frailty at admission had a higher incidence of postoperative VTE (odds ratio [OR]: 2.59, 95% confidence interval [CI]: 1.25-5.39, p = 0.01; I-2 = 66%). Subgroup analysis suggested the association between frailty and postoperative VTE was more remarkable in studies of patients with frailty prevalence < 50% (OR 6.28, 95% CI 3.31-11.90, p < 0.001; I-2 = 8%) as compared to those = 50% (OR 1.30, 95% CI 0.80-2.11, p = 0.28; I-2 = 0%; p for subgroup difference < 0.001). Further meta-analyses showed that frailty at baseline was associated with a higher incidence of deep venous thrombosis (OR 3.15, 95% CI 1.33-7.47, p = 0.009; I-2 = 59%), but not pulmonary embolism (OR 1.13, 95% CI 0.59-2.16, p = 0.72; I-2 = 0%).Conclusion Frailty is associated with a higher incidence of postoperative VTE in patients with hip fracture.