Grant: Project Grant

Background: Obesity is a growing global health problem. It is an important and common risk factor for heart disease and stroke. Weight loss surgery (bariatric surgery) improves risk factors for heart disease, like high blood pressure and diabetes. However, we do not know whether bariatric surgery reduces major clinical events, such as heart attack, stroke or death because randomized controlled trials (RCTs) have not been done. Bariatric surgery is not routinely offered to people with heart disease, due to uncertainty about surgical complications and about its overall benefit. We plan to conduct a large RCT to find out if bariatric surgery reduces the risk of having a future heart attack, stroke, or death in people with heart disease and severe obesity [i.e., body mass index (BMI) of 35 kg/m2 or greater]. However, before such a study can be done, we propose to start with a vanguard phase to determine that conducting the large, definitive trial is feasible. Research question: To show that enrolment into an RCT of bariatric surgery versus medical weight management in people with heart disease and obesity is feasible. Proposed Study: People with obesity and heart disease from centres in Canada and other countries will be randomly selected to either have bariatric surgery in addition to medical care, or medical care alone. People 18 years of age or older, with severe obesity and a history of heart disease, will be included. The vanguard phase will be considered successful if 1) 140 patients are enrolled in 1 year; 2) bariatric surgery can be carried out within 2 months of randomization in >90%; 3) high patient follow-up rates can be achieved. We will also record data on barriers to recruitment and crossover rates. Impact: If the vanguard phase is feasible, we will then carry out the full-scale study to examine whether bariatric surgery compared to medical weight management can reduce death and heart-related complications in people with obesity and heart disease.