LOS ANGELES – A nationwide analysis shows modest early morbidity and low mortality following bariatric surgery in patients with type 2 diabetes who are not morbidly obese.

At 30 days’ follow-up among 1,003 patients, the composite complication rate, defined as the presence of any of 16 adverse events, was 4.2%; the reoperation rate was 1.6%; and two patients (0.2%) died.

“A 2-hour surgical procedure requiring a 2-day hospital stay that is associated with low morbidity and mortality can lead to remission of a chronic, progressive, and disabling disease,” lead author Dr. Ali Aminian of the Cleveland Clinic said at Obesity Week 2015.

“Based on these findings, bariatric surgery can be considered a relatively safe option for managing type 2 diabetes in patients with mild obesity.”

The analysis included adults with a body mass index of at least 25 kg/m², but less than 35 kg/m² (mean, 33 kg/m²).

These data are important because most patients with type 2 diabetes fall into this BMI category, he said.

Most of the patients were women (74.3%), 40% were using insulin, 78% had hypertension, and 9% had cardiac disease, according to the analysis, drawn from the American College of Surgery National Surgical Quality Improvement Program 2005-2013 database.

Roux-en-Y bypass was performed in 574 patients, adjustable gastric banding in 227, sleeve gastrectomy in 189, and duodenal switch in 13.

The most common adverse events overall were blood transfusion and reoperation (both 1.6%), a hospital stay longer than 7 days (0.6%), and organ space surgical-site infection (0.5%).

Composite morbidity and mortality was highest in the Roux-en-Y bypass group, compared with the adjustable banding and sleeve groups (5% vs. 3.1% vs. 3.2%, respectively), Dr. Aminian said at the meeting, presented by the Obesity Society and the American Society for Metabolic and Bariatric Surgery.

Only 3 of 46 patients with a BMI of less than 30 kg/m² had an adverse event.

Available randomized controlled trials can’t clearly resolve the safety concerns of bariatric surgery in the subgroup of patients with type 2 diabetes who are overweight and mildly obese because such small trials are unlikely to reveal uncommon but clinically serious complications, Dr. Aminian said. In addition, many of the trials have screened out low-BMI and high-risk patients.

Those in attendance at the presentation, however, weren’t entirely convinced the current analysis could allay all safety concerns.

Session comoderator Dr. Daniel Cottam, a bariatric surgeon in group practice in Salt Lake City, said, “I like the summary; however, the use of the word ‘safe’ can be taken to mean a lot of things. It’s one of those squishy words.”

Though the authors have shown that bariatric surgery can be performed in diabetics with a low BMI, in order to say it is safe, the comparison needs to be drawn to the all-cause mortality for these patients in the general population and with other surgical procedures.

“That would be useful in the manuscript because as we approach our patients, we want to be able to say, ‘Listen, if you live with diabetes and a BMI of 25-35 for 5 years, this is your all-cause mortality, and surgery is going to save your life, not hurt it,’ ” Dr. Cottam said.

Along the same lines, Dr. Harvey Sugerman emeritus professor of surgery at Virginia Commonwealth University in Richmond, commented, “Like the old days of routinely operating on any patient with diabetes and gallstones, the data were that just having one death in a young person and the quality-of-life-years lost, it would take you thousands of gallbladders to make up for that one death.”

Dr. Sugarmen also asked for details on the deaths including where they occurred, in whom, and whether the centers were inexperienced.

Dr. Aminian could not recall at the time, but in an interview with this news organization said one death was in a 61-year-old with a history of cardiac disease and chronic kidney failure secondary to insulin-dependent diabetes who developed postop bleeding after gastric bypass. The second was in a 59-year-old patient, again on insulin, who was discharged without problems after gastric bypass, but died within 30 days after surgery.

Although most serious complications occur in this period, the main limitation of the study is that the dataset does not capture adverse events beyond 30 days after surgery, which can lead to underestimation of real risk, Dr. Aminian told the crowd.

“Further large clinical studies on long-term safety and efficacy outcomes of bariatric surgery in patients with type 2 diabetes and low BMI are warranted,” he said.

pwendling@frontlinemedcom.com

Short-term adverse events modest after bariatric surgery in slimmer diabetics