Association Between Bariatric Surgery and Macrovascular Disease Outcomes in Patients With Type 2 Diabetes and Severe Obesity

Abstract

<div class="section"> <a class="named-anchor" id="ab-joi180117-1"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e376">Question</h5> <p id="d5657406e378">For patients with severe obesity and type 2 diabetes, is there an association between bariatric surgery and incident macrovascular disease (defined as first occurrence of acute myocardial infarction, unstable angina, percutaneous coronary intervention, coronary artery bypass grafting, ischemic stroke, hemorrhagic stroke, carotid stenting, or carotid endarterectomy)? </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-2"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e381">Findings</h5> <p id="d5657406e383">In this retrospective cohort study of patients with type 2 diabetes and severe obesity that included 5301 who underwent bariatric surgery and 14 934 control patients without surgery, bariatric surgery was associated with a significantly lower risk of macrovascular events at 5 years’ follow-up (2.1% vs 4.3% at 5 years; hazard ratio, 0.60). </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-3"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e386">Meaning</h5> <p id="d5657406e388">Bariatric surgery was associated with a lower risk of incident major macrovascular events. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-4"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e392">Importance</h5> <p id="d5657406e394">Macrovascular disease is a leading cause of morbidity and mortality for patients with type 2 diabetes, and medical management, including lifestyle changes, may not be successful at lowering risk. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-5"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e397">Objective</h5> <p id="d5657406e399">To investigate the relationship between bariatric surgery and incident macrovascular (coronary artery disease and cerebrovascular diseases) events in patients with severe obesity and type 2 diabetes. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-6"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e402">Design, Setting, and Participants</h5> <p id="d5657406e404">In this retrospective, matched cohort study, patients with severe obesity (body mass index ≥35) aged 19 to 79 years with diabetes who underwent bariatric surgery from 2005 to 2011 in 4 integrated health systems in the United States (n = 5301) were matched to 14 934 control patients on site, age, sex, body mass index, hemoglobin A _1c, insulin use, observed diabetes duration, and prior health care utilization, with follow-up through September 2015. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-7"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e410">Exposures</h5> <p id="d5657406e412">Bariatric procedures (76% Roux-en-Y gastric bypass, 17% sleeve gastrectomy, and 7% adjustable gastric banding) were compared with usual care for diabetes. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-8"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e415">Main Outcomes and Measures</h5> <p id="d5657406e417">Multivariable-adjusted Cox regression analysis investigated time to incident macrovascular disease (defined as first occurrence of coronary artery disease [acute myocardial infarction, unstable angina, percutaneous coronary intervention, or coronary artery bypass grafting] or cerebrovascular events [ischemic stroke, hemorrhagic stroke, carotid stenting, or carotid endarterectomy]). Secondary outcomes included coronary artery disease and cerebrovascular outcomes separately. </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-9"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e420">Results</h5> <p id="d5657406e422">Among a combined 20 235 surgical and nonsurgical patients, the mean (SD) age was 50 (10) years; 76% of the surgical and 75% of the nonsurgical patients were female; and the baseline mean (SD) body mass index was 44.7 (6.9) and 43.8 (6.7) in the surgical and nonsurgical groups, respectively. At the end of the study period, there were 106 macrovascular events in surgical patients (including 37 cerebrovascular and 78 coronary artery events over a median of 4.7 years; interquartile range, 3.2-6.2 years) and 596 events in the matched control patients (including 227 cerebrovascular and 398 coronary artery events over a median of 4.6 years; interquartile range, 3.1-6.1 years). Bariatric surgery was associated with a lower composite incidence of macrovascular events at 5 years (2.1% in the surgical group vs 4.3% in the nonsurgical group; hazard ratio, 0.60 [95% CI, 0.42-0.86]), as well as a lower incidence of coronary artery disease (1.6% in the surgical group vs 2.8% in the nonsurgical group; hazard ratio, 0.64 [95% CI, 0.42-0.99]). The incidence of cerebrovascular disease was not significantly different between groups at 5 years (0.7% in the surgical group vs 1.7% in the nonsurgical group; hazard ratio, 0.69 [95% CI, 0.38-1.25]). </p> </div><div class="section"> <a class="named-anchor" id="ab-joi180117-10"> <!-- named anchor --> </a> <h5 class="section-title" id="d5657406e425">Conclusions and Relevance</h5> <p id="d5657406e427">In this observational study of patients with type 2 diabetes and severe obesity who underwent surgery, compared with those who did not undergo surgery, bariatric surgery was associated with a lower risk of macrovascular outcomes. The findings require confirmation in randomized clinical trials. Health care professionals should engage patients with severe obesity and type 2 diabetes in a shared decision making conversation about the potential role of bariatric surgery in the prevention of macrovascular events. </p> </div><p class="first" id="d5657406e431">This cohort study investigates associations between bariatric surgery and incident macrovascular events (coronary artery and cerebrovascular diseases) in patients with type 2 diabetes. </p>