Author + information
- Received May 12, 2010
- Revision received September 7, 2010
- Accepted September 10, 2010
- Published online February 8, 2011.
- Mary M. McDermott, MD⁎,⁎ (, )
- Luigi Ferrucci, MD, PhD†,
- Kiang Liu, PhD⁎,
- Jack M. Guralnik, MD, PhD‡,
- Lu Tian, ScD§,
- Melina Kibbe, MD⁎,
- Yihua Liao, MS⁎,
- Huimin Tao, MS⁎ and
- Michael H. Criqui, MD, MPH∥
- ↵⁎Reprints requests and correspondence:
Dr. Mary M. McDermott, Department of Medicine, Northwestern University Feinberg School of Medicine, 750 North Lake Shore Drive, 10th Floor, Chicago, Illinois 60611
Objectives We hypothesized that women with lower extremity peripheral arterial disease (PAD) would have greater mobility loss and faster functional decline than men with PAD.
Background Whether rates of mobility loss or functional decline differ between men and women with PAD is currently unknown.
Methods Three hundred eighty men and women with PAD completed the 6-min walk, were assessed for mobility disability, and underwent measures of 4-m walking velocity at baseline and annually for up to 4 years. Computed tomography-assessed calf muscle characteristics were measured biannually. Outcomes included becoming unable to walk for 6 min continuously among participants who walked continuously for 6 min at baseline. Mobility loss was defined as becoming unable to walk for a quarter mile or to walk up and down 1 flight of stairs without assistance among those without baseline mobility disability. Results were adjusted for age, race, body mass index, physical activity, the ankle brachial index, comorbidities, and other confounders.
Results At 4 years of follow-up, women were more likely to become unable to walk for 6 min continuously (hazard ratio: 2.30, 95% confidence interval: 1.30 to 4.06, p = 0.004), more likely to develop mobility disability (hazard ratio: 1.79, 95% confidence interval: 1.30 to 3.03, p = 0.030), and had faster declines in walking velocity (p = 0.022) and the distance achieved in the 6-min walk (p = 0.041) compared with men. Sex differences in functional decline were attenuated after additional adjustment for baseline sex differences in calf muscle area.
Conclusions Women with PAD have faster functional decline and greater mobility loss than men with PAD. These sex differences may be attributable to smaller baseline calf muscle area among women with PAD.
Supported by grants R01-HL58099, R01-HL64739, R01-HL071223, and R01-HL076298 from the National Heart Lung and Blood Institute and by grant RR-00048 from the National Center for Research Resources, National Institutes of Health. Supported in part by the Intramural Research Program, National Institute on Aging, National Institutes of Health. The authors have reported that they have no relationships to disclose. Healther L. Gornik, MD, served as Guest Editor for this article.
- Received May 12, 2010.
- Revision received September 7, 2010.
- Accepted September 10, 2010.
- American College of Cardiology Foundation