Biliopancreatic Limb Length as a Potential Key Factor in Superior Glycemic Outcomes After Roux-en-Y Gastric Bypass in Patients With Type 2 Diabetes: A Meta-Analysis

Abstract

Background: Optimal length of biliopancreatic (BP) and Roux limb in Roux-en-Y gastric bypass (RYGB) for improved glycemic control are not known.

Purpose: To investigate how the lengths of the BP and Roux limbs in RYGB differentially affect postoperative glycemic outcomes in patients with type 2 diabetes.

Data sources: We conducted a systematic literature search using the PubMed, Embase, and the Cochrane Library databases.

Study selection: We included studies that reported glycemic outcomes after RYGB and lengths of the BP and Roux limbs.

Data extraction: A total of 28 articles were included for data extraction. Glycemic outcomes after RYGB were assessed on the basis of two definitions: remission and improvement.

Data synthesis: We categorized the included studies into four groups according to the BP and Roux limb lengths. The type 2 diabetes remission/improvement rates were as follows: long BP-long Roux group 0.80 (95% CI 0.70-0.90)/0.81 (0.73-0.89), long BP-short Roux group 0.76 (0.66-0.87)/0.82 (0.75-0.89), short BP-long Roux group 0.57 (0.36-0.78)/0.64 (0.53-0.75), and short BP-short Roux group 0.62 (0.43-0.80)/0.53 (0.45-0.61). Meta-regression analysis also showed that a longer BP limb resulted in higher postoperative type 2 diabetes remission and improvement rates, whereas a longer Roux limb did not. There was no significant difference or heterogeneity in baseline characteristics, including diabetes-related variables, among the four groups.

Limitations: Not all included studies were randomized controlled trials.

Conclusions: Longer BP limb length led to higher rates of type 2 diabetes remission and improvement by 1 year after RYGB in comparisons with the longer Roux limb length.