Bariatric Surgery is Associated with a Reduced Risk of Mortality in Morbidly Obese Patients with a History of Major Cardiovascular Events

Abstract

Although the safety of bariatric surgery in patients with established cardiovascular disease has been demonstrated, little is known about the mid- to long-term survival of these patients after surgery. We conducted a retrospective cohort study of bariatric surgical patients (n = 349) compared with morbidly obese surgical controls (n = 903). Data were obtained on all patients 40 to 79 years of age, from 1996 to 2008, with a diagnosis code of morbid obesity, a primary surgical procedure of interest, and a cardiovascular event history. Data sources were the statewide South Carolina UB92 inpatient hospitalization database and death records. The primary outcome was all-cause mortality. A total of 349 bariatric and 903 control patients with cardiovascular event histories were identified. Among bariatric patients, 19 deaths occurred in 986 person-years of follow-up versus 150 deaths among controls in 3138 person-years of follow-up. Unadjusted all-cause mortality was estimated at 7 ± 2 per cent at 5 years in bariatric patients compared with 19 ± 2 per cent (P < 0.001) in controls. Adjusting for age, comorbidities, and event history, the relative risk of mortality was reduced by 40 per cent in bariatric patients compared with controls [hazard ratios (95% confidence interval): 0.60 (0.36, 0.99)]. In patients with a history of cardiovascular events, bariatric surgery is associated with a significantly decreased risk of all-cause mortality.