Can response to dietary restriction predict weight loss after Roux-en-Y gastroplasty?

Objective: To determine whether weight loss (WL) with 6 weeks of a low-calorie liquid diet as part of a behavioral program (LCDBP) predicts subsequent weight change in response to a laparoscopic Roux-en-Y gastric bypass (RYGB).

Methods: Of 4698 LCDBP patients, 403 went on to RYGB and 222 were evaluable. We determined correlations between percent WL (% WL) in 6 weeks of LCDBP with % WL at 4, 12, 24, 36, and 52 weeks after RYGB.

Results: There was a positive correlation between the slope of WL in the first 6 weeks of LCDBP and over 4 and 12 weeks after RYGB: r = 0.15 (CI = 0.003-0.285, P = 0.045) and r = 0.22 (CI = 0.08-0.35, P = 0.0017), respectively. The association was also apparent at 24 weeks in females but not in males. There was a statistically significant correlation between % WL at 26 weeks of LCDBP and 52 weeks postsurgery (r = 0.20, CI = 0.05-0.34, P = 0.01). Finally, % WL at 6 weeks also predicted % WL at 26 weeks of dietary intervention (r = 0.52, CI = 0.40-0.62, P = 2.40 × 10(-14) ).

Conclusions: WL in response to 6 weeks of LCDBP is predictive of weight for at least 12 weeks following RYGB.