Gastric bypass patients sustain long-term weight loss, comorbidity reduction

A majority of patients who undergo bariatric surgery for the first time maintain significant weight loss through seven years of follow-up, according to a study published Dec. 6 in JAMA Surgery.

Lead researcher Anita P. Courcoulas, MD, MPH, and colleagues studied 2,348 participants at 10 U.S. hospitals. Nearly three-fourths underwent Roux-en-Y gastric bypass (median age 45, 80 percent women) and the other 26 percent received laparoscopic adjustable gastric banding (median age 48, 76 percent women).

The Roux-en-Y gastric bypass (RYGB) patients were a mean 28.4 percent lighter after seven years with a 3.9 percent weight regain occurring in years 3 to 7. Those receiving laparoscopic adjustable gastric banding (LAGB) lost a mean 14.9 percent body weight over seven years, with an average 1.4 percent regain occurring in years 3 to 7. RYGB patients shed an average of 38.2 kilograms, while LAGB patients dropped an average of 18.8 kgs.

In addition, the RYGB group sustained a greater reduction in comorbid conditions over the study period, but the authors cautioned against direct comparison of the procedures due to the nonrandomized nature of the study.

“There are distinct and variable patterns of weight change in response to different surgical treatments, yet most people maintain much of their initial weight loss, with small and variable fluctuations, up to 7 years after the surgical procedure,” Courcoulas et al. wrote. “There are high rates of comorbid disease remission after RYGB, most of which is evident by the first 2 years after surgery, followed by some decline in remission from years 3 to 7, especially for diabetes and hypertension.”

Compared to baseline, the prevalence of five comorbid conditions declined significantly seven years post-RYGB:

• Diabetes declined from 28.3 percent of the patient group to 11.6 percent.
• Hypertension dipped from 67.6 to 51.6 percent.
• High triglycerides dropped from 23.7 to 4.9 percent.
• High LDL cholesterol decreased from 33.3 to 14.3 percent.
• Low HDL cholesterol fell from 34.9 to 5.8 percent.

In comparison, only low HDL cholesterol and high triglyceride prevalence showed significant reductions seven years post-LAGB. Nearly one-third of patients undergoing LAGB needed some surgical revision, while less than one percent of RYGB patients required a bariatric reoperation.

Courcoulas and colleagues charted several distinct weight-loss trajectories for patients in both groups based on annual research assessments.

“Overall, it appears from the initial weight change patterns that the longer-term outcomes in weight may be determined by the magnitude and direction/slope of the initial loss,” they wrote. “These findings point to the need for enhanced and early (years 1-2) postoperative efforts to optimize short-term weight loss trajectory directions that may potentially influence the ability to stay on an optimal weight loss path over the longer term.”