Background

The sleeve gastrectomy (LSG) is rapidly replacing the Roux-en-Y gastric bypass (RYGB) as the most commonly performed weight loss surgery (WLS) procedure. Studies comparing weight regain (WR) between these two procedures are lacking.

Methods

We reviewed the electronic medical records of 3346 patients who had undergone WLS from 2004-2017 in a racially-mixed population at Boston Medical Center. Weight trajectories were characterized by mixed linear model analyses. WR was evaluated by comparing each patient’s weight at sequential visits to nadir weight, taking into consideration the interval during which WR occurred. Adjusted weight regain (AWR) was calculated as a percentage of body weight per 30 day interval. Cox regression analysis (proportional hazards ratio, HR) and generalized equation estimator (Odds ratio, OR) were used to compare the risks of time-to-event and repeated events, respectively.

Results

Relative to the initial weight, weight loss was 3.4% less at nadir in LSG patients. Modest WR was noted within one year of nadir in both groups but increased rapidly for LSG. At 60 months, racial differences were significant with African Americans (AA) experiencing WR of 18.6±3.4% and 6.1 ±0.5% relative to nadir weight after LSG and RYGB, respectively. At the highest quartile AWR, HR was 3.27 (p<0.0001) and OR was 3.64 (p=0.002) for LSG relative to RYGB. Differences were smaller at lower AWR comparisons.

Conclusions

WR starts earlier and is more rapid after LSG than RYGB. These findings appear to be more exaggerated among AA. Prospective studies are needed to help optimize the selection of WLS procedures.