Bariatric surgery improved HbA1c more than intensive medical therapy in obese patients with uncontrolled type 2 DM

Longer-term outcomes show that adding Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy to intensive medical therapy enabled more obese, type 2 diabetes patients to maintain glycemic control. After 3 years of follow-up, only 5% of the patients in the medical-therapy group had an HbA1c of ≤6.0%, compared with 38% of those in the RYGB group and 24% of those in the sleeve-gastrectomy group. Secondary end points, including body weight, use of glucose-lowering medications, and quality of life, also favored the surgical treatments.

The study was published in the New England Journal of Medicine on May 22. The following commentary by B. Gisella Carranza Leon, MD, and Victor M. Montori, MD, MSc, was published in the ACP Journal Club section of the Aug. 19 Annals of Internal Medicine.

Before the emergence of bariatric surgery, remission of type 2 diabetes was not a feasible outcome for obese patients. Bariatric surgery increases the chance of remission 5-fold up to 2 years after surgery (relative risk 5.3, 95% CI 1.8 to 15.8). The STAMPEDE trial, with no major threats to its validity, extends this evidence to up to 3 years after surgery.

Sleeve gastrectomy has emerged as a less aggressive, but less effective, form of bariatric surgery for diabetes remission compared with RYGB. The complications after RYGB include mortality (0.2%), venous thromboembolism (0.4%), and need for reoperation (3% to 5%). Overall, RYGB has a higher incidence of postoperative complications than sleeve gastrectomy (20% vs 10%, odds ratio 1.96, CI 1.26 to 3.04).

Bariatric surgery offers important benefits, including diabetes improvement or remission, to patients with medically complicated obesity for whom weight loss programs are ineffective. The challenge is to identify patients with diabetes who are at high risk for difficulty controlling glycemia and for complications (to justify the perioperative risks and postoperative burdens of these surgeries) and to do so soon after diagnosis when there is a better chance of diabetes remission. Where (e.g., high-volume centers with protocolized postoperative care), when, and which form of surgery to select are subjects for careful deliberation between expert clinicians and informed patients.