WEDNESDAY, Feb. 10, 2016 (HealthDay News) -- Middle-aged and even older people seem to gain a survival boost from gastric bypass surgery -- good news for obese older folks who may wonder if the weight-loss surgery is worth the risk, a new study suggests.
However, the news is not the same for those under 35. The study found no survival benefit for this group, and saw an increase in the number of "externally caused deaths," which included accidental injuries, assaults and suicides. The increase was more significant in women than in men, the researchers said.
"Younger patients, especially females, should be counseled on the risk of suicide and accidental death following bariatric surgery," said Dr. Daniel Schauer, an associate professor of internal medicine at the University of Cincinnati College of Medicine, who reviewed the study findings but was not involved with the research.
At least one doctor suggested that the suicide risk among severely obese younger women might owe to anxiety and depression, and the eventual realization that weight-loss surgery can't eliminate all their problems.
The study wasn't designed to prove a cause-and-effect link between weight-loss surgery and certain survival outcomes. It only showed an association.
The findings appear in the Feb. 10 issue of the journal JAMA Surgery.
The researchers wanted to explore which age groups might gain a survival benefit after undergoing the weight-loss surgery known as Roux-en-Y gastric bypass, particularly because there's not a lot of data on people older than 55. The answers might provide insight into whether older obese people could benefit from weight-loss surgery, which has been linked to improvements in a variety of health conditions, such as type 2 diabetes.
One concern is that the risks of the procedure may outweigh the benefits for obese older people, said Dr. Malcolm Kenneth Robinson, an assistant professor of surgery at Harvard Medical School in Boston, who specializes in weight-loss procedures. Robinson also wasn't involved with the new research, but reviewed the findings.
Robinson also noted that seniors might not live long enough to enjoy the benefits of better health.
In the new study, researchers tracked almost 8,000 severely obese patients who underwent weight-loss surgery in Utah from 1984 to 2002. The study compared their survival rates over seven years to the same number of similarly obese people who didn't have the surgery.
Death from all causes was lower among certain age groups of patients who'd undergone the surgery compared to those who didn't. For people between 35 and 44 years, the odds of death were 46 percent lower during the study period for those who had the surgery. For folks between 45 and 54, the risk of dying during the study period was 57 percent lower after weight-loss surgery. At 55 to 74, the procedure led to a 50 percent lower risk of dying during the study period.
The study didn't calculate how many extra years of life may have been gained by surgical patients. But, study lead author Lance Davidson, an assistant professor with the Department of Exercise Sciences at Brigham Young University in Provo, Utah, said the life span boon was significant for most who underwent surgery.
The one exception was younger people. The rate of death actually went up among those under age 35 who had the surgery. The researchers said the difference wasn't statistically significant, but it did concern them.
The researchers found that people in that younger age group -- especially women -- had a high rate of deaths from external causes, a category that includes accidents and suicides, among other things.
Regarding suicides, Robinson said severely obese young women may suffer from deep-rooted anxiety and depression, and they may "look to surgery to solve all their problems." They might become even more depressed when their problems don't disappear after surgery, he said.
The study only looked at one type of weight-loss surgery. And none of the patients underwent their first weight-loss surgery after 2002. Davidson pointed out that advances in the procedures since then should help improve life spans even more.
Overall, this study's findings are positive, said Schauer. "Not many medical interventions can reduce mortality by 50 percent over the long term," he said.
Robinson said, "If you are older, you can still benefit from having bariatric surgery." However, "you should not wait," he said, echoing one of the conclusions of the study: Don't assume it's OK to delay weight-loss surgery until you're old.
For more about weight-loss surgery, visit the American Society for Metabolic and Bariatric Surgery.