Gender differences in daily ambulatory activity patterns in patients with intermittent claudication

Objectives: To compare the pattern of daily ambulatory activity in men and women with intermittent claudication, and to determine whether calf muscle hemoglobin oxygen saturation (StO(2)) is associated with daily ambulatory activity. Methods: Forty men and 41 women with peripheral arterial disease limited by intermittent claudication were assessed on their community-based ambulatory activity patterns for 1 week with an ankle-mounted step activity monitor and on calf muscle StO(2) during a treadmill test. Results: Women had lower adjusted daily maximal cadence (mean +/- SE) for 5 continuous minutes of ambulation (26.2 +/- 1.2 strides/min vs 31.0 +/- 1.2 strides/min; P = .009), for 1 minute of ambulation (43.1 +/- 0.9 strides/min vs 47.2 +/- 0.9 strides/min; P = .004), and for intermittent ambulation determined by the peak activity index (26.3 +/- 1.2 strides/min vs 31.0 +/- 1.2 strides/min; P = .009). Women also had lower adjusted time to minimum calf muscle StO(2) during exercise (P = .048), which was positively associated with maximal cadence for 5 continuous minutes (r = 0.51; P < .01), maximal cadence for 1 minute (r = 0.42; P < .05), and peak activity index (r = 0.44; P < .05). These associations were not significant in men. Conclusion: Women with intermittent claudication ambulate slower in the community setting than men, particularly for short continuous durations of up to 5 minutes and during intermittent ambulation at peak cadences. Furthermore, the daily ambulatory cadences of women are correlated with their calf muscle StO(2) during exercise, as women who walk slower in the community setting reach their minimum calf muscle StO(2) sooner than those who walk at faster paces. Women with intermittent claudication should be encouraged to not only walk more on a daily basis, but to do so at a pace that is faster than their preferred speed. (J Vase Surg 2010;52:1204-10.)