β-adrenergic blockade is associated with a reduced risk of 90-day mortality after surgery for hip fractures

BACKGROUND: There is a significant postoperative mortality risk in patients subjected to surgery for hip fractures. Adrenergic hyperactivity induced by trauma and subsequent surgery is thought to be an important contributor. By downregulating the effect of circulating catecholamines the increased risk of postoperative mortality may be reduced. The aim of the current study is to assess the association between regular β-blocker therapy and postoperative mortality. METHODS: This cohort study used the prospectively collected Swedish National Quality Registry for hip fractures to identify all patients over 40 years of age subjected to surgery for hip fractures between 2013 and 2017 in Örebro County, Sweden. Patients with ongoing β-blocker therapy at the time of surgery were allocated to the β-blocker-positive cohort. The primary outcome of interest was 90-day postoperative mortality. Risk factors for 90-day mortality were evaluated using Poisson regression analysis. RESULTS: A total of 2443 patients were included in this cohort of whom 900 (36.8%) had ongoing β-blocker therapy before surgery. The β-blocker positive group was significantly older, less fit for surgery based on their American Society of Anesthesiologists classification and had a higher prevalence of comorbidities. A significant risk reduction in 90-day mortality was detected in patients receiving β-blockers (adjusted incidence rate ratio=0.82, 95% CI 0.68 to 0.98, p=0.03). CONCLUSIONS: β-blocker therapy is associated with a significant reduction in 90-day postoperative mortality after hip fracture surgery. Further investigation into this finding is warranted. LEVEL OF EVIDENCE: Therapeutic study, level III; prognostic study, level II.