Background: Bariatric surgery is being conducted more often for morbid obesity, but little evidence exists about how it affects the risk of future cardiovascular events. The goal of this study was to quantify the change in predicted 10-year cardiovascular risk following laparoscopic Roux-en-Y gastric bypass (LRYGBP).
Methods: We conducted a prospective clinical study of morbidly obese adults undergoing LRYGBP at a university hospital in the USA. Our primary outcome measure was mean change in 10-year cardiovascular risk at 12 months. We estimated cardiovascular risk by using the Framingham risk equation, which calculates the absolute risk of cardiovascular events for patients with no known history of heart disease, stroke, or peripheral vascular disease by using information on age, sex, blood pressure, total and high-density lipoprotein cholesterol levels, smoking status, and history of diabetes.
Results: Ninety-two participants underwent LRYGBP between December 2004 and October 2005. Their predicted baseline 10-year cardiovascular risk was 6.7%. At 6 and 12 months, their predicted risk had decreased to 5.2% and 5.4%, respectively. Assuming no change in risk among untreated patients, this represents an absolute risk reduction of 1.3%; which suggests that 77 morbidly obese patients would have to undergo LRYGBP to avert one new case of cardiovascular disease over the ensuing 10 years (number needed to treat = 77).
Conclusion: Our findings indicate that LRYGBP is associated with improvements in cardiovascular risk factors and a corresponding decrease in predicted 10-year risk of cardiovascular disease.