title: Collateral vessel number, plaque burden, and functional decline in peripheral artery disease.
abstract: Associations of collateral vessels and lower extremity plaque with functional decline are unknown. Among people with peripheral artery disease (PAD), we determined whether greater superficial femoral artery (SFA) plaque burden combined with fewer lower extremity collateral vessels was associated with faster functional decline, compared to less plaque and/or more numerous collateral vessels. A total of 226 participants with ankle-brachial index (ABI) <1.00 underwent magnetic resonance imaging of lower extremity collateral vessels and cross-sectional imaging of the proximal SFA. Participants were categorized as follows: Group 1 (best), maximum plaque area < median and collateral vessel number ≥6 (median); Group 2, maximum plaque area < median and collateral vessel number <6; Group 3, maximum plaque area > median and collateral vessel number ≥6; Group 4 (worst), maximum plaque area > median and collateral vessel number <6. Functional measures were performed at baseline and annually for 2 years. Analyses adjust for age, sex, race, comorbidities, and other confounders. Annual changes in usual-paced walking velocity were: Group 1, +0.01 m/s; Group 2, -0.02 m/s; Group 3, -0.01 m/s; Group 4, -0.05 m/s (p-trend=0.008). Group 4 had greater decline than Group 1 (p<0.001), Group 2 (p=0.029), and Group 3 (p=0.010). Similar trends were observed for fastest-paced 4-meter walking velocity (p-trend=0.018). Results were not substantially changed when analyses were repeated with additional adjustment for ABI. However, there were no associations of SFA plaque burden and collateral vessel number with decline in 6-minute walk. In summary, a larger SFA plaque burden combined with fewer collateral vessels is associated with a faster decline in usual and fastest-paced walking velocity in PAD.
authors.affiliation: Northwestern University's Feinberg School of Medicine, Chicago, IL, USA mdm608@northwestern.edu.
authors.forename: Mary M
authors.initials: MM
authors.lastname: McDermott
authors.affiliation: Northwestern University's Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: James
authors.initials: J
authors.lastname: Carr
authors.affiliation: Northwestern University's Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.affiliation: University of Virginia, Charlottesville, VA, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Kramer
authors.affiliation: University of Washington, Seattle, WA, USA University of Washington School of Medicine, Seattle, WA, USA.
authors.forename: Chun
authors.initials: C
authors.lastname: Yuan
authors.affiliation: Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Lu
authors.initials: L
authors.lastname: Tian
authors.affiliation: University of California at San Diego, La Jolla, CA, USA.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Criqui
authors.affiliation: University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
authors.affiliation: National Institute on Aging, Bethesda, MD, USA.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.affiliation: Northwestern University's Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Lihui
authors.initials: L
authors.lastname: Zhao
authors.affiliation: University of Washington School of Medicine, Seattle, WA, USA.
authors.forename: Dongxiang
authors.initials: D
authors.lastname: Xu
authors.affiliation: Northwestern University's Feinberg School of Medicine, Chicago, IL, USA Jesse Brown VA Medical Center, Chicago, IL, USA.
authors.forename: Melina
authors.initials: M
authors.lastname: Kibbe
authors.affiliation: University of Texas Southwestern, Dallas, TX, USA.
authors.forename: Jarett
authors.initials: J
authors.lastname: Berry
authors.affiliation: Northwestern University's Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Carroll
keywords: atherosclerotic plaque; intermittent claudication; peripheral artery disease; physical functioning