Bariatric surgery does more than help obese people shed pounds. According to a new report in the Journal of the American Medical Association, it helps them live longer, too.
Researchers compared 2,500 obese patients who had weight loss surgery to about 7,500 obese patients who did not. All of the volunteers were receiving care at Department of Veterans Affairs medical centers. The researchers gauged their results over a 14-year span.
Patients who had weight loss surgery — 74 percent of them men — had a mean body mass index (BMI) of 47 and a mean age of 52. In the control group, the mean BMI was 46 and the mean age was 53. Fifty-five percent had diabetes. Others had different comorbidities, such as high blood pressure, arthritis, heart disease, or depression.
Compared to those who did not have the procedure, obese patients who had weight loss surgery had a 53 percent lower risk of dying from any cause 5 to 14 years after the surgery. The surgeries covered included gastric bypass, sleeve gastrectomy, adjustable gastric banding, and other bariatric procedures.
Lead study author Dr. David Arterburn, a physician and associate professor of medicine at the University of Washington, said the report shows that older men do just as well after the surgery as younger women do. Previous studies of the effects of weight loss surgery have looked mostly at women. This report sheds light on the impact of this type of weight loss for men and for patients with complications.
“Previous studies of long-term survival after bariatric surgery involved younger, mostly female populations who tended to have few obesity-related diseases,” Arterburn said in a statement to the press.
“We have tracked a large group of patients for a long enough time that we can clearly see a strong link between bariatric surgery and long-term survival,” Arterburn added. “As time passes, the risk of dying among the patients who’ve had surgery appears to be diverging from those of the matched controls who haven’t had surgery.”
Brie Turner-McGrievy, Ph.D., an assistant professor at the University of South Carolina’s Arnold School of Public Health, said the observational design of the study makes it tougher to draw clear conclusions. A randomized, controlled trial would be better for defining cause and effect, but would likely be expensive to conduct.
Also, the new study did not account for factors that impact mortality or those that may be tied to a longer life, such as changes in diet and physical activity, Turner-McGrievy said. She would like to see future studies include a comparison group receiving a behavioral intervention. In this case, the control group did not do anything to lose weight.
“The results point to the importance of finding ways for obese individuals to achieve and maintain a healthy weight loss,” she said.
Bariatric Surgery Is Safer These Days, Too
The researchers also found that the procedures themselves have gotten much safer.
“We found that the risk of dying during and soon after bariatric surgery was lower in 2006-2011 than in 2000-2005,” Matthew Maciejewski, Ph.D., a professor of general internal medicine at Duke University School of Medicine and another researcher involved in the study, said in a statement.
Arterburn and Maciejewski still want to find out if the surgery helps specific subgroups of people more or less. They also want to find out whether the surgery can lower healthcare costs in the long-term. For now, they’re looking at the broader impact of their findings.
“Despite the studies showing that patients with lower BMIs live longer, not much evidence has linked intentional weight loss (from surgery, medication, or diet and exercise) with longer survival,” Arterburn said. “But our results, combined with other studies of bariatric surgery, may help to make that case.”
Is Bariatric Surgery the Only Path to a Longer Life?
Dr. Charlie Seltzer, an obesity medicine physician from Philadelphia, said the results of the study are consistent with research that has shown “again and again that weight loss is associated with decreased death and disease.”
He said that losing weight positively affects endocrine, cardiovascular, and respiratory systems. These systems are harmed by excess weight. While the risks associated with surgery increase with age, the benefits of weight loss persist despite age.
Seltzer said that bariatric surgery is not the only tool for long-term weight loss, or the only way for obese people to boost their longevity. He said that surgery puts people at risk for complications such as vitamin absorption issues, metabolic damage, and acid reflux.
“I have worked with a number of people who lost hundreds of pounds with surgery then gained it all back,” he said. “Over time, the same habits, if not worked on, which got the person into the situation in the first place, will eventually bring them right back there.”