No Association of Diabetic Duration or Insulin Use with the Prognosis of Critical Limb Ischemia after Endovascular Therapy

Abstract

To examine whether diabetic duration and insulin use are independently associated with the prognosis of critical limb ischemia (CLI) after endovascular therapy. 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. 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. Diabetic duration and insulin use were not independent risk factors for the prognosis of CLI after endovascular therapy.