Roux-en-Y gastric bypass (RYGB) surgery yielded greater type 2 diabetes remission in mild or moderately obese patients compared with intensive lifestyle and medical intervention, according to data published in Diabetologia.
The researchers screened 1808 adults aged 25 to 64 years with type 2 diabetes and a body mass index (BMI) ranging from 30 kg/m2 to 45 kg/m2 and allocated 43 participants by concealed, computer-generated random assignment. Participants were assigned to undergo RYGB or intensive lifestyle and medical intervention.
The participants in the intensive lifestyle/medical intervention cohort exercised 5 days per week for at least 45 minutes. Their diet was directed by a dietitian to lower weight and glucose levels, and all participants had optimal diabetes medical treatment for 1 year.
“Our trial and other relevant [randomized controlled trials] demonstrate that commonly used bariatric/metabolic operations (RYGB, sleeve gastrectomy, and gastric banding) are all more effective than a variety of medical and/or lifestyle interventions to promote weight loss, diabetes remission, glycemic control, and improvements in other CVD (cardiovascular disease) risk factors, with acceptable complications, for at least 1 to 3 years,” the authors wrote.
Fifteen participants underwent RYGB and 17 were assigned to the intensive lifestyle/medical intervention. Participants were followed for 1 year, and all were equivalent in baseline characteristics, although the RYGB cohort had a longer diabetes duration (11.4 vs 6.8 years; P=.009).
The percentage of weight loss at 1 year was 25.8% among participants who underwent RYGB and 6.4% in the intensive lifestyle/medical intervention group (P<.001). Participants in the intensive lifestyle/medical intervention exercise program had a 22% increase in VO2max (P<.001), while the VO2max levels in the RYGB group remained unchanged.
The rate of diabetes remission at 1 year was 60% in the RYGB group and 5.9% with the intensive lifestyle/medication intervention (P=.002). HbA1c declined in the RYGB cohort from 7.7% (60.7 mmol/mol) to 6.4% (46.4 mmol/mol), and the intensive lifestyle/medication intervention cohort’s HbA1 declined from 7.3% (56.3 mmol/mol) to 6.9% (51.9 mmol/mol), although the decrease occurred with fewer diabetes medications after RYGB (P=.04).
“These results apply to patients with a BMI <35 kg/m2, and our study and others show that neither baseline BMI nor the amount of weight lost dependably predicts diabetes remission after RYGB, which appears to ameliorate diabetes through mechanisms beyond just weight reduction,” the authors noted.
“These findings call into serious question the longstanding practice of using strict BMI cutoffs as the primary criteria for surgical selection among patients with type 2 diabetes.”