The relationship between free-living daily physical activity and the severity of peripheral arterial occlusive disease

The purposes of this study were to assess the magnitude of the reduction in free-living daily physical activity of claudicants compared with age- matched controls, and to examine the relationship between the severity of peripheral arterial occlusive disease (PAOD) and free-living daily physical activity. Eighty-five PAOD patients with intermittent claudication and 59 non-PAOD subjects with a resting ankle/brachial index (ABI) of 0.63 ± 0.20 and 1.21 ± 0.08, respectively, were monitored for 2 consecutive weekdays with an accelerometer and pedometer worn on each hip. The times to onset and to maximal claudication pain were also measured in the claudicants during a graded treadmill test to assess the functional limitations imposed by PAOD. The PAOD group had a 42% lower energy expenditure as measured from the accelerometer (357 ± 238 kcal/day versus 616 ± 363 kcal/day; p < 0.001) and a 45% lower pedometer reading (4737 ± 2712 steps/day versus 8672 ± 4235 steps/day; p < 0.001) than the non-PAOD group. Furthermore, the relationship between free-living daily physical activity and ABI in PAOD patients was significant for both the accelerometer (r = 0.41; p < 0.001) and the pedometer (r = 0.41; p < 0.001). The rate of decline in free-living daily activity was 42 kcal/day and 612 steps/day per 0.10 drop in ABI. The correlation between free-living daily physical activity and time to maximal claudication pain (6:25 ± 3:30 min:s) in the PAOD group was significant for both the accelerometer (r = 0.30; p = 0.05) and the pedometer (r = 0.36; p = 0.03). However, the time to onset of claudication pain (3:02 ± 2:22 min:s) in the PAOD group was not related to either the accelerometer (r= -0.02; p = 0.86) or the pedometer (r= 0.18; p = 0.28) activity values. In conclusion, free-living daily physical activity was 42% to 45% lower in PAOD patients with intermittent claudication than in apparently healthy subjects of similar age. Moreover, claudicants were progressively more sedentary with an increase in PAOD severity.