Acid suppression medications are associated with suboptimal weight loss after laparoscopic Roux-en-Y gastric bypass in patients older than 40 years.

Background: Bariatric surgery, including laparoscopic Roux-en-Y gastric bypass (LRYGB), achieves the greatest long-term weight loss in severe obesity. Approximately 50%-60% of severely obese patients have gastroesophageal reflux disease, and a substantial proportion is taking a proton pump inhibitor (PPI) or histamine-2 blocker (H2 B) at the time of LRYGB. The objective of this study was to explore the association of PPI/H2 B use before LRYGB with suboptimal percent weight loss (PWL) after LRYGB.

Methods: This was a cohort study of 472 consecutive patients who underwent LRYGB at a single center from 2004-2011. Suboptimal PWL was defined as<14% at 2 months,<25% at 6 months, and<30% at 12 months. Because of effect modification by age, stratified analyses (by median age of 40 yr) were performed. All models were adjusted for appropriate covariates, including obesity-associated co-morbidities.

Results: For patients aged ≤40 years, PPI/H2 B use leading up to LRYGB was not associated with suboptimal PWL at 2 months (P = .86), 6 months (P = .47), or 12 months (P = .66). However, for patients aged>40 years, PPI/H2 B use leading up to LRYGB was associated with a nonsignificant increase in suboptimal PWL at 2 months (odds ratio [OR] 2.23; P = .08) and significant increases in suboptimal PWL at 6 months (OR 7.23; P = .002) and 12 months (OR 11.1; P = .02). Results were independent of GERD.

Conclusions: Mechanisms for the poorer weight loss in patients aged>40 years who were using a PPI/H2 B just before LRYGB should be explored.