Effect of standard vs extended Roux limb length on weight loss outcomes after laparoscopic Roux-en-Y gastric bypass

Background: Increasing the length of the Roux limb in open Roux-en-Y gastric bypass (RYGB) effectively increases excess weight loss in superobese patients with a body mass index (BMI) >50 kg/m². Extending the RYGB limb length for obese patients with a BMI < 50 could produce similar results. The purpose of this study was to compare the outcomes of superobese patients undergoing laparoscopic RYGB with standard (≤100-cm) with those undergoing the procedure with an extended (150-cm) Roux limb length over 1-year period of follow-up. Methods: Retrospective data over 2.5 years were reviewed to identify patients with a BMI < 50 who underwent primary laparoscopic RYGB with 1-year follow-up (n = 58). Forty-five patients (sRYGB group) received limb lengths ≤ 100 cm, including 45 cm (n = 1), 50 cm (n = 2), 60 cm (n = 6), 65 cm (n = 1), 70 cm (n = 1), 75 cm (n = 3), and 100 cm (n = 31). Thirteen patients (eRYGB group) received 150-cm limbs. Postoperative weight loss was compared at 3 weeks, 3 months, 6 months, and 1 year. Results: Comparing the sRYGB vs the eRYGB group (average ± SD), respectively: There were no significant differences in age (41.5 ± 11.0 vs 38.0 ± 11.9 years), preoperative weight (119.2 ± 11.9 vs 127.8 ± 12.5 kg), BMI (43.7 ± 3.0 vs 45.2 ± 3.5 kg/m²), operative time (167.1 ± 72.7 vs 156.5 ± 62.4 min), estimated blood loss (129.9 ± 101.1 vs 166.8 ± 127.3 cc), or length of stay (median, 3 vs 3 days; range, 2–18 vs 3–19). Body weight decreased over time in both groups, except in the sRYGB group between 3 and 6 months and 6 and 12 months after surgery and in the eRYGB group between 6 and 12 months. BMI also decreased over time, except in the eRYGB group between 6 and 12 months. Absolute weight loss leveled out between 6 and 12 months in both groups, with no increase after 6 months. Percent of excess weight loss did not increase in the eRYGB group after 6 months. An extended Roux limb did not significantly affect body weight, BMI, absolute weight loss, or precent of excess weight loss at any time point when the two groups were compared. A trend toward an increased proportion of patients with >50% excess weight loss (p = 0.07) was observed in the extended Roux limb group. Conclusions: In this series, no difference in weight loss outcome variables were observed up to 1 year after laparoscopic RYGB. Thus, extending Roux limb length from ≤100 cm to 150 cm did not significantly improve weight loss outcome in patients with a BMI < 50 kg/m².