The Impact of Hemoglobin A1c on Post-operative Outcomes in Bariatric Surgery Patients

Abstract

Pre-operative hemoglobin (Hb) A1c levels ≥ 8% can lead to increased post-operative complications. In bariatric surgery patients, attaining a pre-operative HbA1c < 8% can be a challenge. The purpose of this study was to identify the association of pre-operative HbA1c on post-operative outcomes in bariatric surgery patients. A retrospective chart review was conducted on diabetic patients (HbA1c ≥ 6.5%) who underwent primary bariatric surgery at a single institution between the years 2013 and 2019. Patients were divided into two groups based on their pre-operative HbA1c levels of < 8% and ≥ 8%. Univariate analyses were performed to determine an association between pre-operative HbA1c levels and post-operative outcomes. There were 351 primary diabetic bariatric surgery patients, 270 HbA1c <8%, and 81 HbA1c ≥ 8%. Procedure selection was significantly different between the HbA1c < 8% and HbA1c ≥ 8% group (49.3% sleeve, 50.4% bypass and 0.4% band versus 43.2% sleeve, 53.1% bypass and 3.7% band respectively, P < 0.04). There was no statistically significant difference in any 30-day post-operative outcome between the two groups. Post-operative HbA1c was significantly less in the HbA1c < 8% group at 3-6 month (6.0% ± 0.9 versus 7.4% ± 1.4, P <0.001) and 6-12 month (6.0% ± 1.1 versus 7.2% ± 1.4, P <0.001) follow-up. This study demonstrated no difference in post-operative outcomes of primary bariatric surgery patients based on a HbA1c cut-off of 8%. This highlights that bariatric surgery can be considered and safely performed in patients with a pre-operative HbA1c ≥ 8%.