Obese patients with type 2 diabetes might reap greater health-care savings after weight-loss surgery than obese patients without diabetes, researchers say.
Most health-care systems use a high body mass index (BMI) to prioritize patients for weight-loss ("bariatric") surgery. BMI is a measure of body fat based on height and weight.
But researchers who tracked thousands of obese Swedes for 15 years concluded that if containing health costs is the goal, then type 2 diabetes, especially newly diagnosed cases, should be added to the reasons to consider weight-loss surgery.
"In obese patients with type 2 diabetes, the costs of bariatric surgery are largely offset by prevention of future health care and drug use," said study researcher Dr. Lena Carlsson, a researcher at the University of Gothenburg, Sweden.
"In contrast, obese patients without diabetes treated by bariatric surgery had higher total health-care costs compared to those who had conventional treatment," Carlsson added.
Other research has found weight-loss surgery can help people reverse their type 2 diabetes, a condition characterized by abnormal blood sugar levels. This reduces the need for medicine and overall health care, the researchers said. And in this study, health-care savings were more apparent in people with more recent diabetes diagnoses.
"What they are saying is, we should use functional markers to determine who gets bariatric surgery, and BMI is not the best one to use," said Dr. Mitchell Roslin, chief of obesity surgery at Lenox Hill Hospital in New York City. "I would agree with that statement," said Roslin, who was not involved in the study.
Because obesity is linked to serious diseases -- including diabetes -- weight-loss surgery is often recommended for severely obese people unable to lose weight through lifestyle changes or medication. Surgery can lead to weight loss by restricting the amount of food the stomach can hold. The most common bariatric procedures are gastric bypass, sleeve gastrectomy, adjustable gastric band and biliopancreatic diversion, according to the American Society for Metabolic and Bariatric Surgery.
The current study involved about 2,000 obese adults who underwent bariatric surgery between 1987 and 2001, and more than 2,000 obese adults treated nonsurgically. Nearly 600 had prediabetes and another 600 had diabetes.
The study results were published online Sept. 17 in The Lancet: Diabetes & Endocrinology.
The researchers looked at patients' drug costs, hospital costs and overall health-care costs for 15 years.
Drug costs were lower in the surgery patients with prediabetes (by about $3,300) or diabetes (by about $5,400) compared to surgical and nonsurgical patients without diabetes, the investigators found.
Hospital costs were higher in all surgical patients. (The surgery currently costs about $20,000 to $30,000, said Roslin.)
When compared with patients treated nonsurgically, total health-care costs were higher for surgery patients who had prediabetes (by more than $26,000) or no sign of diabetes (by more than $22,000), but not for those with diabetes at the time of surgery, the findings showed.
"The results of our study support prioritization of obese patients for bariatric surgery, especially those with recent diabetes onset," Carlsson said.
Another study researcher, Dr. Martin Neovius of the Karolinska Institute in Sweden, said the idea of prioritizing patients with diabetes "makes not only sense from a health outcome perspective, but also economically."
Criteria vary, he said, but some experts already suggest that people with a BMI of 30 to 35 and type 2 diabetes should be considered candidates for bariatric surgery. The society for metabolic and bariatric surgery recommends the surgery for someone with a BMI of 40 or higher (for example, 5 feet 11 and 290 pounds), or a BMI of 35 and higher with two other conditions (such as type 2 diabetes and high blood pressure).
In the United States, insurance companies typically have their own criteria for covering the surgery, Roslin said. The findings of the new report, he said, would apply to countries such as Canada, which have a national health plan and waiting lists.