The role of alimentary and biliopancreatic limb length in outcomes of Roux-en-Y gastric bypass

Roux-en-Y gastric bypass (RYGB) is one of the safe and easily reproducible bariatric procedures. To evaluate the effect of biliopancreatic limb (BPL) and alimentary limb (AL) length on weight loss outcomes after RYGB. This retrospective cohort study included 313 morbidly obese patients who underwent primary laparoscopic RYGB 2009-2015. Patients' BPL and AL lengths were categorized into three groups: group 1 (BPL: 50 cm and AL: 150 cm), group 2 (BPL: 150 cm and AL: 50 cm), and group 3 (BPL: 100 cm and AL: 100 cm). Data were provided from the Iranian National Obesity Surgery Database. The generalized estimating equations method was used to assess the effect of limbs length on %excess weight loss (%EWL). Mean ± standard deviation age and body mass index (BMI) of 252 patients were 38.55 ±10.24 years and 45.8 ±4.77 kg/m , respectively. Totally, 172 (68.3%, BMI of 46 ±5 kg/m ), 48 (19%, BMI of 45.12 ±4.26 kg/m ), and 32 (12.7%, BMI of 45.43 ±4.23 kg/m ) were in group 1, 2, and 3, respectively (p = 0.44). The results showed that the choice of different limb lengths had no significant effect on %EWL over 12 months follow-up (p = 0.625) adjusted for baseline BMI (p = 0.25). Mean %EWL in the patients with longer BPL and shorter AL was 5.43% (1.91, 8.95) higher in comparison to the patients with shorter BPL and longer AL during 36 months postoperatively adjusted for baseline BMI (p = 0.002). During 12 months after RYGB, %EWL was not associated with BPL or AL length. However, during 36 months postoperatively, the patients with longer BPL had a significantly higher %EWL in comparison to the patients with shorter BPL.