Background

Bariatric surgery can lead to remission of type 2 diabetes mellitus (T2DM) but we do not yet know which bariatric procedure may be best for patients with T2DM.

Methods

Using electronic health record data, we identified adults (age 20-79 years) with T2DM who underwent a primary sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), or adjustable gastric banding (AGB) at 34 health systems in the National Patient-Centered Clinical Research Network (PCORnet®) from 1/1/05 through 9/30/15. The primary outcome was cumulative T2DM remission. Secondary outcomes included relapse of T2DM (in those who achieved remission) and change in HbA1c.

Results

10,018 patients were in the final cohort, including 6233 RYGB, 3477 SG, 308 AGB. The cohort was primarily female (73%), White (72%), with an average age of 49.9 years.Adjusted cumulative initial diabetes remission rates for RYGB and SG were 59.2% (95% CI: 57.7 to 60.7) and 55.9% (53.9 to 57.9) 1 year post-surgery; 84.3% (82.9 to 85.5) and 81.5% (79.6 to 83.2) at 3 years and 86.1% (84.7 to 87.3) and 83.5% (81.6 to 85.1) at 5 years. In AGB patients, cumulative remission was 65% or less over 5 years. Compared with AGB, remission rates were approximately doubled for RYGB [HR 2.19 (1.89 to 2.53)] and SG [HR 1.85 (1.53 to 2.25)]. Cumulative diabetes relapse rates among RYGB and SG patients were 8.4% (7.4 to 9.3) and 11.0% (9.6 to 12.4), respectively, 1 year post-remission; 21.2% (19.1 to 23.2) and 27.2% (24.1 to 30.1) at 3 years; and 33.1% (29.6 to 36.5) and 41.6% (36.8 to 46.1) at 5 years. Approximately 1 in 4 AGB patients with diabetes remission relapsed within a year; 3 in 4 relapsed within 5 years. Patients experienced the largest and most-sustained HbA1c reductions after RYGB, followed by SG then AGB.

Conclusions

RYGB and SG resulted in approximately double the initial diabetes remission rates of AGB over 5 years. RYGB patients had less diabetes relapse and better long-term glycemic control than SG and AG patients.