Association of Surgical Treatment with Adverse Events and Mortality among Medicare Beneficiaries with Proximal Humerus Fracture

Abstract

Importance: Meta-analyses of randomized clinical trials suggest that the advantages and risks of surgery compared with conservative management as the initial treatment for proximal humerus fracture (PHF) vary, or are heterogeneous across patients. Substantial geographic variation in surgery rates for PHF suggests that the optimal rate of surgery across the population of patients with PHF is unknown. Objective: To use geographic variation in treatment rates to assess the outcomes associated with higher rates of surgery for patients with PHF. Design, Setting, and Participants: This comparative effectiveness research study analyzed all fee-for-service Medicare beneficiaries with proximal humerus fracture in 2011 who were continuously enrolled in Medicare Parts A and B for the 365-day period before and immediately after their index fracture. Data analysis was performed January through June 2019. Exposure: Undergoing 1 of the commonly used surgical procedures in the 60 days after an index fracture diagnosis. Main Outcomes and Measures: Risk-adjusted area surgery ratios were created for each hospital referral region as a measure of local area practice styles. Instrumental variable approaches were used to assess the association between higher surgery rates and adverse events, mortality risk, and cost at 1 year from Medicare's perspective for patients with PHF in 2011. Instrumental variable models were stratified by age, comorbidities, and frailty. Instrumental variable estimates were compared with estimates from risk-adjusted regression models. Results: The final cohort included 72823 patients (mean [SD] age, 80.0 [7.9] years; 13958 [19.2%] men). The proportion of patients treated surgically ranged from 1.8% to 33.3% across hospital referral regions in the United States. Compared with conservatively managed patients, surgical patients were younger (mean [SD] age, 80.4 [8.1] years vs 78.0 [7.2] years; P