No association of diabetic duration or insulin use with the prognosis of critical limb ischemia after endovascular therapy

Abstract

Aim: To examine whether diabetic duration and insulin use are independently associated with the prognosis of critical limb ischemia (CLI) after endovascular therapy. Methods: We recruited 312 Japanese patients who underwent endovascular therapy for CLI. The outcome measures were major amputation and mortality. Cox proportional hazards regression analyses were performed. Results: The prevalence of diabetes mellitus (DM) was 69%, and 47% of the DM population were treated with insulin. DM patients with insulin use had hemoglobin A1c (HbA1c) of 7.5±1.3% and diabetic duration of 21±11 years, whereas those without insulin use had HbA1c of 6.6±1.4% and diabetic duration of 19±11 years. Follow-up period was 93±72 weeks; 55 patients underwent major amputations and 102 died. Diabetic duration and insulin use had significant associations with major amputation in each univariate model, with an unadjusted hazard ratio (HR) and 95% confidence interval (CI) of 1.019 [1.000, 1.039] in one-year increments and 2.321 [1.368, 3.938], respectively. In the multivariate model, however, diabetic duration and insulin use were not significantly associated with limb prognosis, as HbA1c level was, with an adjusted HR [95% CI] of 1.332 [1.114, 1.593] in 1% increment. Mortality had no statistical association with any of these DM-related variables. Conclusion: Diabetic duration and insulin use were not independent risk factors for the prognosis of CLI after endovascular therapy.