Relationship between varying Roux limb lengths and weight loss in gastric bypass

BACKGROUND: The optimal Roux limb length for gastric bypass is unknown. Therefore, the effect of Roux limb length on weight loss and nutritional deficiency after a Roux-en-Y gastric bypass procedure was studied. METHODS: From September 2000 to February 2004, 165 Roux-en-Y gastric bypass surgeries were performed at William Beaumont Army Medical Center. One-year follow-ups were completed on 97 patients. Roux limbs varied from 100 cm to 150 cm, based on the patient's body mass index (BMI). Roux limb lengths were compared with 1-year changes in absolute weight, BMI, and nutritional levels. RESULTS: In the 97 patients, average age at the time of surgery was 44 years (range, 20-63). Average BMI was 46.7 +/- 6.6 kg/m(2) before surgery and 30.9 +/- 5.8 kg/m(2) at 1-year follow-up. Average absolute weight loss at 1 year was 43.7 +/- 12.8 kg. A statistically significant linear relationship existed between Roux limb length and reductions in BMI and absolute weight. No relationship existed between Roux limb length and changes in nutrient levels. CONCLUSION: A linear relationship exists between Roux limb length and 1-year weight loss.