Bariatric Surgery vs Lifestyle Intervention for Diabetes Treatment: 5-Year Outcomes From a Randomized Trial

Abstract

Context: Questions remain about bariatric surgery for type 2 diabetes mellitus (T2DM) treatment.

Objective: Compare the remission of T2DM following surgical or nonsurgical treatments.

Design, setting, and participants: Randomized controlled trial at the University of Pittsburgh, in the United States. Five-year follow-up from February 2015 until June 2016.

Interventions: 61 participants with obesity and T2DM who were initially randomized to either bariatric surgical treatments (Roux-en-Y gastric bypass [RYGB] or laparoscopic adjustable gastric banding [LAGB]) or an intensive lifestyle weight loss intervention (LWLI) program for 1 year. Lower level lifestyle weight loss interventions (LLLIs) were then delivered for 4 years.

Main outcomes and measures: Diabetes remission assessed at 5 years.

Results: The mean age of the patients was 47 ± 6.6 years, 82% were women, and 21% African American. Mean hemoglobin A1c level 7.8% ± 1.9%, body mass index (BMI) 35.7 ± 3.1 kg/m2, and 26 participants (43%) had BMI < 35 kg/m2. Partial or complete T2DM remission was achieved by 30% (n = 6) of RYGB, 19% (n = 4) of LAGB, and no LWLI participants (P = .0208). At 5 years those in the RYGB group had the largest percentage of individuals (56%) not requiring any medications for T2DM compared with those in the LAGB (45%) and LWLI (0%) groups (P = .0065). Mean reductions in percent body weight at 5 years was the greatest after RYGB 25.2% ± 2.1%, followed by LAGB 12.7% ± 2.0% and lifestyle treatment 5.1% ± 2.5% (all pairwise P < .01).

Conclusions: Surgical treatments are more effective than lifestyle intervention alone for T2DM treatment.

Trial registration: ClinicalTrials.gov NCT01047735.

Keywords: Obesity; bariatric; randomized controlled trial; type 2 diabetes mellitus.