Optimal medical therapy predicts amputation-free survival in chronic critical limb ischemia

• Published in: Journal of vascular surgery 2013-10, Vol.58 (4), p.972-980
• Main Authors: Chung, Jayer, MD, Timaran, David A., MD, Modrall, J. Gregory, MD, Ahn, Chul, PhD, Timaran, Carlos H., MD, Kirkwood, Melissa L., MD, Baig, Mirza S., MD, Valentine, R. James, MD
• Format: Article
• Language: English
• Subjects: Amputation - mortality; Cardiovascular Agents - therapeutic use; Chronic Disease; Critical Illness; Disease-Free Survival; Female; Guideline Adherence; Humans; Ischemia - mortality; Ischemia - surgery; Ischemia - therapy; Kaplan-Meier Estimate; Limb Salvage; Male; Middle Aged; Multivariate Analysis; Practice Guidelines as Topic; Practice Patterns, Physicians; Proportional Hazards Models; Risk Assessment; Risk Factors; Smoking Cessation; Surgery; Texas; Time Factors; Treatment Outcome
• ISSN: 0741-5214; 1097-6809
• DOI: 10.1016/j.jvs.2013.03.050

Objective Determine the proportion of patients with chronic critical limb ischemia (CLI) who failed to adhere to Trans-Atlantic Inter-Society Consensus II guidelines of medical therapy and to quantify the effect of baseline suboptimal medical management on amputation-free survival (AFS). Methods The patients were identified from a prospectively maintained database of consecutive patients presenting with CLI to the Vascular Surgery service at a single hospital. The primary outcome variable was AFS. The effects of baseline demographics, comorbid medical conditions, ambulatory status, optimal medical management, and Rutherford classification were assessed. Significant univariate predictors ( P  < .10) of AFS were entered into a multivariate Cox proportional hazards model. Results From August 1, 2010 through January 1, 2012, 98 patients (median age, 59.0; interquartile range, 53, 64 years; 58 men) were evaluated with rest pain (n = 40) or tissue loss (n = 58). Optimal medical management was identified in 31 (32%) patients at initial presentation. Compliance rates for the entire cohort were 61% for statin use, 69% for antiplatelet therapy, 56% for angiotensin-converting enzyme inhibitor use, and 53% for beta-blocker use. Significant univariate predictors of major amputation or death included: Rutherford classification (hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.01-2.41; P = .04); nonambulatory status (HR, 2.17; 95% CI, 1.68-2.81; P < .01); unrevascularized patients (HR, 2.77; 95% CI, 1.32-5.85; P < .01); a history of tobacco abuse (HR, 1.49; 95% CI, 0.57-3.86; P = .09); a history of end-stage-renal disease (HR, 7.97; 95% CI, 3.10-20.52; P < .01); suboptimal medical management (HR, 4.25; 95% CI, 1.28-14.07; P = .02); and an absence of antiplatelet agents (HR, 1.94; 95% CI, 0.92-4.11; P = .08). Independent predictors of major amputation or death included: initial nonambulatory status (HR, 2.43; 95% CI, 1.03-2.05; P < .01); unrevascularized status (HR, 2.43; 95% CI, 1.76-3.34; P = .01); and suboptimal medical management at presentation (HR, 8.54; 95% CI, 2.05-35.65; P < .01). Conclusions Despite guidelines advocating the optimization of atherosclerotic risk factors, less than one-third of patients with CLI present with their risk factors optimally managed. Patients who are medically undertreated have an eight-fold risk of major amputation and/or death. The magnitude of the effect suggests that future trials and quality assessments should stratify out