Andrew M Ibrahim, MD, Amir A Ghaferi, MD, MS, Jyothi Thumma, MPH, Justin B Dimick, MD, MPH. University of Michigan, Center for Healthcare Outcomes & Policy
Introduction: As bariatric surgery continues to grow among the most common operations in the United States, increased attention is being given to the associated perioperative risk. One strategy to improve quality for this population is to restrict bariatric procedures to Centers of Excellence (COEs.) Little is known, however, about how much variation exists across these COEs.
Methods: We performed a retrospective review of surgical outcomes at COEs across 9 states performing 1 of 3 common bariatric procedures between 2009-2011. Data was obtained from the Healthcare Cost and Utilization Project – State Inpatient Database and Medicare Provider Analysis and Review file which included unique hospital identification numbers allowing comparisons across 254 Centers of Excellence. For each hospital, we calculated the risk and reliability adjusted serious complications rates within 30 days of the index operation. A multilevel regression model was utilized to assess the variation in outcomes across COEs within each state.
Results: Wide variation exists across COEs for bariatric surgery. For example, the risk and reliability adjusted complication rates at COEs in the State Inpatient Database varied 28 fold (N=148; range 0.3% to 8.6%) with top and bottom quintiles differing by 3.4 fold (top quintile 0.8% ; bottom quintile 2.7%; p<0.005.) We repeated the analysis among Medicare beneficiaries and found similar COE variation; hospital level post-operative complications varied 13 fold (N=254; range 1.4% to 13.7%) with top and bottom quintiles differing by 2 fold (top quintile 2.4%; bottom quintile 4.7% ; p<0.005.) Each individual state also demonstrated significant variation in post-operative complications rates ranging from 2.6 fold (MA; top quintile 1.0 to bottom quintile 2.6%; p<0.005.) to 4.6 fold (FL; top quintile 0.8% to bottom quintile 3.7%; p<0.005.)
Conclusions: Even within Centers of Excellence for bariatric surgery, wide variation exists in serious post-operative complications. Restricting patients to COEs may not achieve desired quality improvement intended by professional organizations. Additionally, like non-COEs, COEs would benefit from substantial quality improvement interventions to reduce variation.