Researchers from Northwestern University Feinberg School of Medicine, Chicago, USA, found that women with peripheral artery disease have faster functional decline and greater mobility loss than men with the same disease. These sex differences may be attributable to smaller baseline calf muscle area among women. The study was published in the February 2011 issue of the Journal of the American College of Cardiology.
Mary M. McDermott, lead author of the study, and a team of researchers observed 380 men and women with peripheral artery disease for four years, measuring their calf muscle characteristics and leg strength every year. The researchers also tracked whether or not the patients could walk for six minutes without stopping and climb up and down a flight of stairs without assistance every year.
The results shown that women were more likely to become unable to walk for 6 minutes 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-minute walk (p = 0.041) compared with men.
“After four years, women with peripheral artery disease were more likely to become unable to walk for six minutes continuously and more likely to develop a mobility disability compared to men with the disease,” said McDermott “When we took into account that the women had less calf muscle than men at the beginning of the study, that seemed to explain at least some of the gender difference.
Interestingly, men in this study experienced a greater loss of calf muscle annually than the women. But the men had more lower extremity muscle reserve than the women. That may have protected men against the more rapid functional decline women experienced.
We know that supervised treadmill exercise can prevent decline, so it’s especially important for women with peripheral artery disease to get the diagnosis and engage in walking exercise to try and protect against decline,” McDermott recommended.