The effect of Roux limb lengths on outcome after Roux-en-Y gastric bypass: A prospective, randomized clinical trial

Background: The effect of limb-length on weight loss after Roux-en-Y gastric bypass (RYGBP) is controversial; hence, the optimal limb-lengths have not been determined. This study evaluated the effect of different limb-lengths on weight loss after RYGBP. Methods: The study was a prospective randomized clinical trial in which patients undergoing RYGBP (110 F, 24 M; mean age 39.7) were randomized as follows: BMIless than or equal to50 (N=69): A-75 cm (N=35) vs B-150 cm alimentary limb (N=34) and C-150 cm (N=33) vs D-250 cm alimentary limb (N=31). All other aspects of the operation were identical. Patients were followed at 2 weeks, 6 weeks, 6 months, 12 months, 18 months, 24 months and yearly thereafter. Results: There were no significant differences in age, sex, race, initial BMI, or excess weight between patients assigned to groups A vs B and C vs D. Postoperative nutritional intake was also similar between groups. Within each weight category, there were no differences in mean weight loss, change in BMI, and % excess weight lost (EWL) over time. When the number of patients achieving 50% EWL was evaluated, there was no difference between groups with a BMI less than or equal to50 kg/m(2); however, among patients with a BMI >50 kg/m(2), a significantly greater percentage of those having a 250-cm limb achieved >50% EWL at 18 months postoperatively. This difference was lost at 24 and 36 months, possibly due to the small sample size. Conclusions: In patients with a BMI less than or equal to50, there appears to be no advantage to longer limb-lengths. In patients with BMI >50, however, these data suggest that longer alimentary limb-lengths may be associated with a higher percent of patients achieving >50% EWL. Longer follow-up studies of the effects of limb-length on success of RYGBP are indicated.