Clinicians can expect "substantial" weight loss in severely obese patients 3 years after they undergo Roux-en-Y gastric bypass but less impressive weight loss 3 years after laparoscopic adjustable gastric banding, according to a report published online Nov. 4 in JAMA.
In a multicenter follow-up study of 2,348 such patients, those who underwent Roux-en-Y gastric bypass (RYGB) lost a median of 31.5% of their baseline weight and those who underwent laparoscopic adjustable gastric banding (LAGB) lost a median of 15.9% of their baseline weight at 3 years, said Dr. Anita P. Courcoulas of the department of surgery, University of Pittsburgh Medical Center, and her associates.
"Because our patient population was diverse and our results were from a large number of surgeons and surgical centers, long-term sustained weight loss can be expected from RYGB, and the results are likely generalizable. [However,] weight loss associated with the LAGB procedure was less than anticipated ... and less than what would be expected based on published series," the investigators noted.
Dr. Courcoulas and her colleagues in the Longitudinal Assessment of Bariatric Surgery consortium performed this observational cohort study at 10 hospitals across the United States. A total of 1,738 adults underwent RYGB, and 610 underwent LAGB. The median age was 46 years (range, 18-78 years). Most of the study subjects were women (79%), and 14% were nonwhite.
After 3 years, patients in the RYGB group lost a median of 41 kg (range, 110-kg loss to a 1-kg gain). Most of that loss occurred during the first postsurgical year, and typically there was "mild" weight regain between years 2 and 3.
Patients in the LAGB group lost a median of 20 kg (range, 75-kg loss to a 20-kg gain). Most of that loss also occurred during the first postsurgical year, with less than 20% of patients losing much weight after that. Typically, that weight loss was maintained between years 2 and 3, the investigators said (JAMA 2013 Nov. 4 [doi:10.1001/jama.2013.280928]).
Approximately 67% of patients in the RYGB group had at least partial remission of diabetes at year 3, a percentage similar to that reported in the literature. In contrast, only 27% of those in the LAGB group had at least partial remission of diabetes at year 3, which is a substantially lower rate than the 73% reported in the literature.
At the same time, 0.9% of patients in the RYGB group and 3.2% of those in the LAGB group developed new-onset diabetes during follow-up.
Approximately 62% of the RYGB group had remission of dyslipidemia, while 3.2% developed new-onset dyslipidemia. In contrast, only 27% of the LAGB group had remission of dyslipidemia, while 16% developed new-onset dyslipidemia. The pattern was similar for hyperlipidemia.
Approximately 38% of the RYGB group had remission of hypertension, while 13% developed new-onset hypertension during follow-up. For the LAGB group, the proportion of new-onset cases of hypertension (18.1%) actually exceeded the proportion of remissions (17.4%).
Concerning adverse events, three deaths occurred within 30 days of an RYGB procedure, and two revision procedures and two reversal procedures were required during 3-year follow-up. The corresponding figures for LAGB were zero postsurgical deaths and 77 surgeries to remove the band or revise the surgery during follow-up.
This study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases. Dr. Courcoulas reported ties to Allergan, Covidien, EndoGastric Solutions, Ethicon J & J Healthcare System, Nutrisystem, and Pfizer, and her associates reported ties to several industry sources.