Importance: Severe obesity (body mass index [BMI] ≥35) is associated with a broad range of health risks. Bariatric surgery induces weight loss and short-term health improvements, but little is known about long-term outcomes of these operations.
Objective: To report 3-year change in weight and select health parameters after common bariatric surgical procedures.
Design and setting: The Longitudinal Assessment of Bariatric Surgery (LABS) Consortium is a multicenter observational cohort study at 10 US hospitals in 6 geographically diverse clinical centers. PARTICIPANTS AND EXPOSURE: Adults undergoing first-time bariatric surgical procedures as part of routine clinical care by participating surgeons were recruited between 2006 and 2009 and followed up until September 2012. Participants completed research assessments prior to surgery and 6 months, 12 months, and then annually after surgery.
Main outcomes and measures: Three years after Roux-en-Y gastric bypass (RYGB) or laparoscopic adjustable gastric banding (LAGB), we assessed percent weight change from baseline and the percentage of participants with diabetes achieving hemoglobin A1c levels less than 6.5% or fasting plasma glucose values less than 126 mg/dL without pharmacologic therapy. Dyslipidemia and hypertension resolution at 3 years was also assessed.
Results: At baseline, participants (N = 2458) were 18 to 78 years old, 79% were women, median BMI was 45.9 (IQR, 41.7-51.5), and median weight was 129 kg (IQR, 115-147). For their first bariatric surgical procedure, 1738 participants underwent RYGB, 610 LAGB, and 110 other procedures. At baseline, 774 (33%) had diabetes, 1252 (63%) dyslipidemia, and 1601 (68%) hypertension. Three years after surgery, median actual weight loss for RYGB participants was 41 kg (IQR, 31-52), corresponding to a percentage of baseline weight lost of 31.5% (IQR, 24.6%-38.4%). For LAGB participants, actual weight loss was 20 kg (IQR, 10-29), corresponding to 15.9% (IQR, 7.9%-23.0%). The majority of weight loss was evident 1 year after surgery for both procedures. Five distinct weight change trajectory groups were identified for each procedure. Among participants who had diabetes at baseline, 216 RYGB participants (67.5%) and 28 LAGB participants (28.6%) experienced partial remission at 3 years. The incidence of diabetes was 0.9% after RYGB and 3.2% after LAGB. Dyslipidemia resolved in 237 RYGB participants (61.9%) and 39 LAGB participants (27.1%); remission of hypertension occurred in 269 RYGB participants (38.2%) and 43 LAGB participants (17.4%).
Conclusions and relevance: Among participants with severe obesity, there was substantial weight loss 3 years after bariatric surgery, with the majority experiencing maximum weight change during the first year. However, there was variability in the amount and trajectories of weight loss and in diabetes, blood pressure, and lipid outcomes.
Trial registration: clinicaltrials.gov Identifier: NCT00465829.