Objective: Evaluate the long-term effects of bariatric surgery on type 2 diabetes (T2DM) remission and metabolic risk factors.
Background: Although the impressive antidiabetic effects of bariatric surgery have been shown in short- and medium-term studies, the durability of these effects is uncertain. Specifically, long-term remission rates following bariatric surgery are largely unknown.
Methods: Clinical outcomes of 217 patients with T2DM who underwent bariatric surgery between 2004 and 2007 and had at least 5-year follow-up were assessed. Complete remission was defined as glycated hemoglobin (A1C) less than 6% and fasting blood glucose (FBG) less than 100 mg/dL off diabetic medications. Changes in other metabolic comorbidities, including hypertension, dyslipidemia, and diabetic nephropathy, were assessed.
Results: At a median follow-up of 6 years (range: 5–9) after surgery (Roux-en-Y gastric bypass, n = 162; gastric banding, n = 32; sleeve gastrectomy, n = 23), a mean excess weight loss (EWL) of 55% was associated with mean reductions in A1C from 7.5% ± 1.5% to 6.5% ± 1.2% (P < 0.001) and FBG from 155.9 ± 59.5 mg/dL to 114.8 ± 40.2 mg/dL (P < 0.001). Long-term complete and partial remission rates were 24% and 26%, respectively, whereas 34% improved (>1% decrease in A1C without remission) from baseline and 16% remained unchanged. Shorter duration of T2DM (P < 0.001) and higher long-term EWL (P = 0.006) predicted long-term remission. Recurrence of T2DM after initial remission occurred in 19% and was associated with longer duration of T2DM (P = 0.03), less EWL (P = 0.02), and weight regain (P = 0.015). Long-term control rates of low high-density lipoprotein, high low-density lipoprotein, high triglyceridemia, and hypertension were 73%, 72%, 80%, and 62%, respectively. Diabetic nephropathy regressed (53%) or stabilized (47%).
Conclusions: Bariatric surgery can induce a significant and sustainable remission and improvement of T2DM and other metabolic risk factors in severely obese patients. Surgical intervention within 5 years of diagnosis is associated with a high rate of long-term remission.
After a median follow-up of 6 years in 217 severely obese patients with type 2 diabetes (T2DM), bariatric surgery (gastric bypass, gastric banding, and sleeve gastrectomy) resulted in complete remission [A1C (glycated hemoglobin) < 6%, FBG (fasting blood glucose) < 100 mg/dL] in 24%, partial remission (A1C = 6.0%–6.4%, FBG = 100–125 mg/dL) in 26%, improvement (>1% decrease in A1C) in 34%, and no change in 16%. Recurrence occurred in 19% of patients after achieving remission, but 75% who recurred maintained an A1C less than 7%. Shorter duration of T2DM and weight loss were predictors of complete remission.
*Bariatric and Metabolic Institute and
†Endocrinology and Metabolism Institute, Cleveland Clinic, Cleveland, OH; and
‡Department of Surgery, Loyola University, Chicago, IL.
Reprints: Stacy A. Brethauer, MD, Bariatric and Metabolic Institute, Cleveland Clinic, 9500 Euclid Avenue, M61, Cleveland, OH 44195. E-mail: firstname.lastname@example.org.
Disclosure: No funding was received for this work. The authors declare no conflicts of interest.