title: Prevalent peripheral arterial disease and inflammatory burden.
abstract: Strong evidence implicates inflammation in the development of atherosclerotic heart disease but less is known about peripheral arterial disease (PAD). Our objective was to test the hypothesis that a composite index of inflammatory burden is associated with PAD.
  
  
  
  Cross-sectional analysis of a randomly-selected group of 903 community-dwelling men in the MrOS cohort recruited between 2000 and 2002. Using blood samples, we measured seven cytokines and related these levels to prevalent PAD (ankle-brachial index (ABI) <0.9) both individually and as part of an "inflammatory burden score" (a composite sum of the number of pro-inflammatory cytokines in the highest quartile).
  
  
  
  Overall, 6.75% of men had ABI <0.9. The odds of prevalent PAD were higher in men with the highest quartile (Q4) levels of interleukin-6 multivariable (MV) adjusted (odds ratio (OR) =3.95 (95% CI, 1.4-11.3), tumor necrosis factor alpha OR = 4.44 (95% confidence interval (CI), 1.5-12.8), and C-reactive protein OR = 3.63 (95% CI, 1.4-9.4) compared to men in Q1. The magnitude of the association of these cytokines with PAD was similar to the effect of being 10 years older, OR = 2.41 (95% CI, 1.16-3.7). These significant effects persisted after additional MV adjustment for smoking except for CRP. Men with the highest inflammatory burden score (≥3) had 3.6 (95% CI, 1.5-8.7) increased odds of PAD, p trend = 0.03. After smoking adjustment the linear trend was borderline statistically significant (p trend = 0.10).
  
  
  
  Inflammatory burden is associated with prevalent PAD, an association similar to aging 10 years. The inflammatory effects of smoking contributes to the underlying association between inflammation and PAD.
authors.affiliation: Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, A510 Crabtree Hall, Pittsburgh, PA, 15261, USA. jcauley@edc.pitt.edu.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Cauley
authors.affiliation: Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto Street, A510 Crabtree Hall, Pittsburgh, PA, 15261, USA.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Kassem
authors.affiliation: University of California Davis Health System, 4625 2nd Avenue, Suite 2006, Sacramento, CA, 95817, USA.
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Lane
authors.affiliation: Family Medicine of Southwest, Peacehealth Southwest Medical Center, 400 NE Mother Joseph Place, Vancouver, WA, 986664, USA.
authors.forename: Sara
authors.initials: S
authors.lastname: Thorson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood; D055109:Ankle Brachial Index / Q000379:methods; D002097:C-Reactive Protein / Q000378:metabolism; D003430:Cross-Sectional Studies; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology; D018836:Inflammation Mediators / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D058729:Peripheral Arterial Disease / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology*; D015995:Prevalence; D011897:Random Allocation; D012307:Risk Factors
chemical_list: C508600:IL6 protein, human; D018836:Inflammation Mediators; D015850:Interleukin-6; D002097:C-Reactive Protein
keywords: Ankle-arm index; Ankle-brachial index; Cytokine; Inflammation; Men; Peripheral arterial disease; Peripheral vascular disease; Smoking