Diabetes mellitus (DM) and peripheral arterial disease (PAD) are independently associated with increased risk of amputation. However, the effect of poor glycemic control on adverse limb events has yet to be fully defined. In this study, we examined the effects of poor glycemic control as defined by high hemoglobin A1c (HbA1c ≥ 7.0%) on the risk of amputation and need for subsequent revascularization after lower extremity revascularization. Patients undergoing PAD revascularization who had HbA1c levels available within 6 months before or after revascularization were identified in the VA database from 2003 to 2014 (N = 26,799). The diagnosis of preoperative DM (pre-op DM) was defined using a primary clinic DM diagnosis code, 2 outpatient diagnosis codes or treatment for DM before the revascularization. Major amputation and major adverse limb event (MALE, amputation or need for subsequent revascularization) risk was measured at 30 days, 1 year, and 5 years after revascularization. Cox proportional hazards models were created to assess the effect of high HbA1c on amputation/MALE (adjusted for covariates, including age, sex, race, socioeconomic status, comorbidities, cholesterol levels, creatinine, supra/infrainguinal procedure, open/endovascular procedure and medications) for all patients and stratified on pre-op DM. High HbA1c levels were present in 33.2% of the cohort while 26.5% had pre-op DM. Major amputations occurred in 4359 (16.3%) patients, and 10,580 (39.5%) had MALE in follow-up. Bivariate comparisons showed increased risk of amputation at 30 days, 1 year, and 5 years for patients with high HbA1c (5.8% vs 3.9%, 14.9% vs 9.0% and 21.1% vs 12.2%, respectively; P < .0001). MALE was also similarly higher in patients with high HbA1c at each time point (11.4% vs 8.8%, 32.6% vs 25.6% and 44.4% vs 34.8%, respectively; P < .0001). Kaplan-Meier curves showed worst outcomes in patient with pre-op DM and high HbA1c. In the Cox model, High HbA1c was associated with a 77% higher amputation risk and 33% higher MALE risk compared with patients with normal glycemic control while a preoperative diagnosis of DM was associated with a 53% and 22% increase in amputation and MALE risk as shown in the Table. In stratified analysis the relative risk of amputation/MALE was much higher with poor glycemic control in patients without a preoperative diagnosis of diabetes as compared with those with it (Table). Patients with PAD who have poor perioperative glycemic control (HbA1c ≥7.0%) have a significantly higher risk of amputation and MALE than patients with good glycemic control. Poor glycemic control in patients without a preoperative diagnosis of DM carries twice the relative risk of amputation and MALE than those with good glycemic control. These results suggest that screening of diabetic status and management of glycemic control could be a target for improvement of perioperative and long-term outcomes in patients with PAD.TableCox proportional hazards regression model: hazard ratios (HR) for occurrence of major amputation or major adverse limb events (MALE) with poor glycemic control (HbA1c ≥7%) in peripheral arterial disease (PAD) patients undergoing revascularizationFull modelAmputation, HR (95% confidence interval)MALE, HR (95% confidence interval)Poor glycemic control1.77 (1.65, 1.90)1.33 (1.27, 1.39)Pre-op DM1.53 (1.42, 1.65)1.22 (1.16, 1.28)Stratified by preoperative diagnosis of diabetes mellitus (PreopDM) No diagnosis of pre-op DMPoor glycemic control2.11 (1.92, 2.31)1.43 (1.35, 1.51) Pre-op DM diagnosis presentPoor glycemic control1.34 (1.20, 1.50)1.18 (1.09, 1.28)DM, Diabetes mellitus. Open table in a new tab