When endocrinologist Mary Elizabeth Patti evaluates a patient with type 2 diabetes who might benefit from weight loss, she considers more than just body mass index and blood glucose levels. She understands the social challenges that could influence treatment decisions, such as low income, food insecurity, and limited access to healthcare. These factors are strongly linked to the development of type 2 diabetes and obesity.
For over a decade, Patti has led extensive randomized clinical trials across four U.S. cities, comparing bariatric surgery to medication and lifestyle management for type 2 diabetes. In 2024, one of these trials highlighted the superiority of bariatric surgery, showing lower blood glucose levels, greater weight loss (28% versus 10%), reduced use of diabetes medications, remission of diabetes, and decreased cardiovascular risk factors.
New Insights from Ongoing Research
A recent secondary analysis of a larger trial, published in the Annals of Internal Medicine, explored how social determinants of health affected outcomes after bariatric surgery compared to medical therapy for people with type 2 diabetes and obesity. The findings revealed that bariatric surgery was more effective than medical therapy across all social backgrounds, not just in areas of higher deprivation.
The study faced limitations such as a smaller participant group and some crossover between medical and surgical treatments. Additionally, the rapid development of more potent obesity drugs was not fully captured in the study. Despite these factors, Patti emphasized, “Bariatric surgery remains an underutilized approach. Even in comparison to these really wonderful medications that we now have access to, it is still better.”
Understanding the Study’s Framework
The comprehensive study began in Boston, Cleveland, Pittsburgh, and Seattle, enrolling 355 participants who were randomly assigned to medical therapy or one of three surgical approaches: gastric bypass, sleeve gastrectomy, or adjustable gastric lap banding. Medical interventions included personalized nutrition counseling and exercise guidance based on the Diabetes Prevention Program.
Over time, fewer participants opted for lap band surgery, which has since fallen out of favor, while newer obesity drugs became increasingly available. By year 12, over a third of participants in the medical therapy groups and more than a quarter in the surgical groups were using incretin-based therapy, including older drugs like liraglutide and newer GLP-1s like tirzepatide.
Surgical Outcomes and Socioeconomic Factors
The smaller study analyzed data from 258 adults with type 2 diabetes who participated in the larger trial, sorted by ZIP codes to identify their Area Deprivation Index. Their weight and hemoglobin A1c levels were tracked for seven to 12 years. While surgery showed a trend toward better outcomes for those in high deprivation areas, it was not statistically significant.
Patti noted the complexities of managing diabetes, especially with socioeconomic challenges. Patients face dietary modifications that may strain family budgets, and exercise can be challenging for those working multiple jobs. The healthcare environment also poses difficulties, even for insured individuals, in maintaining consistent access to medications.
“If you don’t have an advocate in the healthcare system and you really don’t have a way to keep up with the need for approvals or prior authorizations, being an advocate for yourself — that’s really hard when you are having many social, financial and other stressors,” Patti said.
Future Directions in Diabetes Treatment
Amid the excitement surrounding GLP-1 drugs, surgery might not be the first choice for patients, regardless of their socioeconomic status. However, for those aiming to lose significant weight, surgery offers a more likely solution. Melanie Jay, a professor at New York University, highlighted the chronic nature of obesity, emphasizing that it often requires lifelong management.
“Obesity is a disease that often needs to be managed lifelong. We don’t have a cure yet, right?” Jay remarked.
The biological mechanisms behind surgery and medical therapy are similar, both reducing appetite and enhancing GLP-1 hormone secretion, which aids in diabetes control. Surgery offers a sustained method to activate these mechanisms without the side effects or insurance hurdles associated with medications.
Jason Samuels, a professor of surgery at Vanderbilt, stressed the underutilization of all obesity therapies. He pointed out that while bariatric surgery has a proven track record, it reaches only a small fraction of eligible patients, and medications do not benefit everyone who could use them.
“Ultimately, we need large, long-term, well-designed studies to clarify the best strategy for a given patient,” Samuels stated.
As the conversation around diabetes treatment evolves, Patti advocates for keeping surgery in the discussion. She cites epidemiological studies showing its effectiveness in improving diabetes control, remission, and survival. The focus, she suggests, should be on finding the best choice for each individual patient.
