150-OR: Mean HbA1c and Glycaemic Variability Are Associated with Adverse Outcomes following Infrainguinal Bypass for Peripheral Arterial Disease (PAD)—A Retrospective Cohort Study

Abstract

Introduction: Glycemic variability (GV) is associated with increased risk of several adverse outcomes in people with diabetes (DM). However, on the impact of GV on graft patency following infra-inguinal bypass (IIB) for peripheral arterial disease (PAD) is unknown. Methods: A 3-year single centre retrospective case notes analysis of those undergoing IIB 2017-2019. HbA1c values for 5 years pre-procedure (minimum of 3) were used to calculate a mean (±SD) HbA1c (MH) and GV. Time to re-intervention, ipsilateral amputation or death were recorded to determine primary (PP) and secondary patency (SP). Results: 193 IIB outcomes were analysed: mean (±SD) age 68.9 (9.2) years; 135 (69.9%) male. 156 (80.8%) had pre-operative HbA1c for analysis and 88 (45.6%) had DM; 87 (45.1%) were current smokers; 107 (55.4%) underwent emergency procedures. Those without diabetes were more likely to smoke (P=0.011), but those with DM had higher Rutherford stage (p<0.01), underwent more distal bypasses (p<0.01) and more emergency procedures (p=0.04). Those with DM had longer mean [IQR] hospital stays 9 [5-21] vs 7 [4-15] days (p=0.017), lower PP 335 [184-542] vs 883 [436-1437] days (p=0.04) and lower SP 751 [387-1108] vs 1079 [895-1593] days (p=0.037). Both MH and GV were associated with amputation free survival time (r=-0.232, p=0.004 and r=-0.243, p=0.011 respectively). A GV>9.1% was associated with significantly lower PP than GV<9.1%, 198[105-377] vs 713 [313-1287] days (p=0.02). On multivariate adjustment, GV >9.1% and level of bypass remained independent predictors of primary patency, HR 1.96 (95% CI:1.12-3.42, p=0.018) and HR 2.54 (95%CI:1.24-5.22, p=0.038) respectively. Conclusions: We have shown a significant relationship between MH and GV and risk of adverse outcomes in people undergoing IIB. Lowering glycemic variability should be an additional therapeutic target together with lowering mean HbA1c. Disclosure K.Dhatariya: Other Relationship; Novo Nordisk, AstraZeneca, Boehringer-Ingelheim, Eli Lilly and Company. P.C.Bennett: None. D.J.Farndon: None.