title: Mortality in patients with premature lower extremity atherosclerosis.
abstract: OBJECTIVE
  Lower extremity peripheral artery disease occurs mostly in the elderly and is associated with high mortality. Limited data are available regarding long-term mortality in patients with premature lower extremity atherosclerosis (PLEA). Our objective was to determine the all-cause mortality and its predictors in younger PLEA patients.
  
  
  METHODS
  We studied patients with severe PLEA who were <55 years of age at diagnosis and treated at a single academic vascular center between 1998 and 2010. Data were collected prospectively at the initial evaluation for vascular care. National Death Index and hospital records were used to determine all-cause mortality. Demographic and clinical characteristics were summarized using count (%), mean (standard deviation), or median (interquartile range), and associations with aspirin use were tested using χ2 test, t-test, or Wilcoxon test. Survival times were estimated using Kaplan-Meier estimates, and associations with covariates were tested using simple and multivariable Cox proportional hazards models.
  
  
  RESULTS
  A total of 564 patients were analyzed (46% female; 20% nonwhite; mean age 49.4 [6.4] years). Ninety-five percent of patients had ≥2 cardiovascular risk factors, 31% had coronary artery disease (CAD), and 10% had a history of cancer. During median follow-up of 5.6 years (interquartile range, 2.3-8.3 years), 108 deaths (19%) were recorded. Two-year estimated mortality (standard error) was 6% (0.01), and 5-year estimated mortality was 16% (0.02). In univariate regression analysis, patient age (P=.04), prior amputation (P<.01), history of cancer (P=.03), and established CAD (P=.04) were associated with increased risk of mortality. Aspirin use and lipid-lowering therapy at the time of first evaluation were associated with improved survival (P<.01 and P=.02, respectively). A multivariable Cox proportional hazards model identified age (hazard ratio [HR] for 5-year increase, 1.17; 95% CI, 1.01-1.36; P=.04), prior amputation (HR, 1.99; 95% CI, 1.18-3.34; P=.01), history of cancer (HR, 2.35; 95% CI, 1.36-4.07; P<.01), and CAD (HR, 1.76; 95% CI, 1.16-2.67; P<.01) as independent predictors of mortality in patients with PLEA. Importantly, history of aspirin use had a significant protective effect (HR, 0.45; 95% CI, 0.30-0.69; P<.01). The impact of lipid-lowering therapy was no longer significant in multivariable modeling.
  
  
  CONCLUSIONS
  Patients with PLEA demonstrate high all-cause mortality. No traditional cardiovascular risk factors predicted mortality. Aspirin therapy at the time of first evaluation was a significant and independent predictor of improved survival in patients with PLEA.
authors.affiliation: Division of Vascular Surgery, Department of Surgery, NYU Langone Medical Center, New York, NY, USA.
authors.forename: Hamza
authors.initials: H
authors.lastname: Rana
authors.forename: Jeanette S
authors.initials: JS
authors.lastname: Andrews
authors.forename: Billy G
authors.initials: BG
authors.lastname: Chacko
authors.forename: Kimberley J
authors.initials: KJ
authors.lastname: Hansen
authors.forename: Pavel J
authors.initials: PJ
authors.lastname: Levy
mesh_terms: D000046:Academic Medical Centers; D000328:Adult; D017668:Age of Onset; D001241:Aspirin / Q000627:therapeutic use; D002317:Cardiovascular Agents / Q000627:therapeutic use; D016009:Chi-Square Distribution; D015897:Comorbidity; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009657:North Carolina; D058729:Peripheral Arterial Disease / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors
chemical_list: D002317:Cardiovascular Agents; D001241:Aspirin