Elevated Hb A1C level and revisional bariatric surgery complications

Background: Elevated Hb A1C is a modifiable risk factor for postoperative complications. However, in bariatric surgery, as published by our group and others, elevated preoperative Hb A1C may not be associated with increased postoperative complications. Previous literature has focused on primary bariatric surgery and has excluded the higher-risk revisional surgery cohort. Objective: To assess the impact of Hb A1C on early postoperative outcomes in patients requiring revisional bariatric surgery. Setting: Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database. Methods: We undertook a retrospective review of patients undergoing revisional bariatric surgery between 2017 and 2018 from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database. Two groups were studied, defined by Hb A1C cutoff, ≤8% versus >8% and ≤10% versus >10%. Early postoperative complications were compared at each threshold, with the primary outcome defined as a composite of all complications. Propensity score matching (PSM) was used with one-to-one matching for covariates, and the complication rates before and after PSM were calculated and assessed by Fisher's exact test and conditional logistic regression, respectively. Results: A total of 16,234 patients had undergone revisional bariatric surgery. After PSM, elevated Hb A1C was not associated with worse outcomes. No significant difference was seen in the composite outcomes for Hb A1C ≤8% versus Hb A1C >8% (P = .22) or for patients with Hb A1C ≤10% versus Hb A1C >10% (P < .46). There were no differences in individual outcomes such as surgical-site infections, cardiopulmonary complications, or readmissions/reinterventions. Conclusion: In this study of revisional bariatric patients, elevated Hb A1C >8% or >10% was not associated with increased postoperative complications. Prospective studies are needed to investigate this further.