Weight Loss Surgery Slashes Risk Of Coronary Heart Disease By 40%

Researchers from the Cleveland Clinic have found that weight loss surgery in obese individuals dramatically improves several cardiovascular risk factors, reducing the 10-year risk of coronary heart disease by an estimated 40%.

The study, which was published online last month in the American Journal of Cardiology, involved the analysis of 52 studies comprising more than 16,000 patients who had undergone bariatric surgery between 1950 and 2010. The researchers looked at how various measures of cardiovascular health changed following the procedure.

Immediately prior to surgery, the patients had an average BMI of 49 with 28% suffering diabetes and almost half with hypertension. Bariatric surgery resulted in average excess weight loss of 52%. The researchers also found that surgery resulted in dramatic reductions in the incidence of diabetes, hypertension, and dyslipidemia, with improvements or resolution in 75%, 68%, and 71% of patients respectively.

Average fasting glucose levels improved from 126 mg/dL prior to surgery to 92 mg/dL after surgery, a reduction of 27%. Blood pressure improved from an average of 139/87 to 124/77, while LDL cholesterol levels lowered from 118mg/dL to 94mg/dL. Levels of inflammation in the body, as measured by C-reactive protein showed the most dramatic improvement, dropping more than 60% from 4.5mg/L to 1.7mg/L.

The researchers found that the improvements in cardiovascular risk factors amounted to a 40% reduction in the 10 year risk of coronary heart disease calculated using the Framingham risk score. This corresponded to a reduction in the absolute risk of 10 year CHD from 6.27% to 3.77%.

Lead author Dr. Helen M. Heneghan of the Bariatric and Metabolic Institute at the Cleveland Clinic believes that some physicians and cardiologists are reluctant to recommend weight loss surgery to their patients because they are not fully aware of the cardiovascular benefits. According to Heneghan: “We hope that after reading this, physicians will recognize that their obese patients with cardiovascular risk factors or established cardiovascular disease would benefit immensely from weight loss surgery”.

Previous studies have shown similar improvements following bariatric surgery. A 2007 study, published in the New England Journal of Medicine found a 40% reduction in all cause mortality over an average follow-up of 7 years. That study found a 56% reduction in deaths from coronary artery disease, a 60% reduction in cancer deaths, and a 90% reduction in diabetes related deaths.

Although the risk of serious complications or even death is not insignificant, the above studies show that for those who survive the initial surgery, the long term prognosis is very good, far better than it would’ve been had the patient not undergone the procedure.

Historically, the death rate from bariatric procedures has hovered around 0.5% however this has improved to less than 0.3% in recent decades due to improved surgical techniques. Complications immediately following bariatric surgery are relatively common but with appropriate management are not normally life threatening. Complications include gall stones, blood clots, bowel obstruction, stomach ulcers, and anastomotic leaks (the leakage of intestinal fluids into the abdomen).

Risk factors for serious complications or death during, or after surgery include: extreme obesity (BMI>50), age greater than 50, male gender, and co-morbidities such as congestive heart failure, coronary artery disease, diabetes or peripheral vascular disease.