Weight-loss surgery yields lasting improvement in health, studies say

Fifteen years after they have weight-loss surgery, almost a third of patients who had Type 2 diabetes at the time they were operated on remain free of the metabolic disorder, a new study says. And six years following such surgery, patients had shaved their probability of suffering a heart attack over the next 10 years by 40%, their stroke risk by 42%, and their likelihood of dying over the next five years by 18%, additional research has concluded.

The two studies, both presented Wednesday at the annual meeting of the American Society for Metabolic and Bariatric Surgery in Atlanta, offer the first indications of weight-loss surgery’s longer-term health benefits for patients. While researchers have demonstrated dramatic improvements in many bariatric patients’ metabolic function in the short term, the durability of those improvements has been unclear.

Research suggests that over several years, many bariatric patients regain some of the weight they lose in the first two years -- a fact that has raised doubts about the cost-effectiveness of the surgery, which can cost $20,000 to $25,000 for the initial procedure, plus a wide range of costs to treat complications after surgery.

The new studies’ findings that patients’ health prospects remain better for several more years may make weight-loss surgery a more appealing treatment for insurers to cover, and for obese patients with health concerns to seek out.

The study that followed 604 bariatric patients in Sweden for 15 years found that in the first two years after surgery, 72% achieved diabetes remission: They were able to cease taking medication for the metabolic condition. After 15 years, a little more than half of those had diabetes again. But 31% had remained in remission.

By contrast, only 16% of the comparison group -- similarly obese patients with diabetes who did not get surgery -- had seen their diabetes remit in the first two years. At 15 years out, diabetes remission was six times likelier in those who had surgery than in the those who did not.

In another study, researchers at the Cleveland Clinic in Ohio followed bariatric patients for an average of six years after surgery. They tallied those patients’ likelihoods of developing a wide range of health outcomes at the time of surgery and six years later, and compared them. To do so, they used the Framingham risk calculator to estimate the before-and-after 10-year risks of heart disease, stroke, death, kidney disease and complications such as diabetic retinopathy and poor circulation.

(The Framingham risk calculator is derived from probabilities gleaned from following more than 10,000 subjects in Framingham, Mass., in the Framingham Heart Study, which started in 1948.)

In this study, the bariatric patients lost 60% of their excess weight and 61% saw their diabetes remit after surgery. Overall, their risk of having coronary heart disease, stroke or peripheral heart disease dropped by 27%.

Bariatric surgeon Dr. John Morton, a professor of medicine at Stanford University who was not involved in either study, suggested that the results of more modern bariatric surgical procedures may be superior. He added that reducing the stress of obesity on the body, even if some weight returns, may improve a patient’s long-term health prospects.

“Carrying extra weight can carry forth year to year,” said Morton, who is president-elect of the American Society for Metabolic and Bariatric Surgery. He likened long-term obesity to smoking cigarettes for years, suggesting that the number of years a person remains obese (or smokes) may interact with their degree of obesity (or how much they smoke) to influence his or her likelihood of developing health problems.

“Any removal of that extra weight and inflammation is a help,” Morton said.

[For the Record, 10:28 a.m. PST Nov. 14: A previous version of this post incorrectly said the new studies on weight-loss surgery were presented at the Obesity Society’s annual meeting. They were presented at the annual meeting of the American Society for Metabolic and Bariatric Surgery. The two groups both were meeting in Atlanta as part of an event called Obesity Week.]