The effect of supervised exercise therapy on physical activity and ambulatory activities in patients with intermittent claudication.

OBJECTIVE/BACKGROUND: Intermittent claudication (IC) is associated with a reduction in physical activity (PA) and a more rapid functional decline leading to a higher mortality rate compared with healthy individuals. Supervised exercise therapy (SET) is known to increase the walking capacity of patients with IC. However, it is unclear whether SET increases PA. The aim of this study was to investigate the effect of SET on PA levels and ambulatory activities in patients with IC. METHODS: Patients newly diagnosed with IC were requested to wear an activity monitor 1 week prior to and 1 week immediately after 3 months of SET. The primary outcome was the percentage of patients meeting the minimum recommendations of PA (American College of Sports Medicine [ACSM]/American Heart Association [AHA] recommendation for public health of ≥ 67 metabolic equivalents [METs]/min/day, in bouts of ≥ 10 min) at baseline and after 3 months of SET. Additionally, daily PA level (METs/min), duration of ambulatory activities, daily number of steps, pain free walking distance (PFWD), maximal walking distance (MWD), and Short Form Health Survey (SF-36) health surveys were compared before and after SET. RESULTS: Data from 41 participants were available for analysis. A higher number of participants met the ACSM minimum recommendation for PA at the 3 month follow up (baseline: 43%; 3 months: 63%; p = .003). Despite significant increases in PFWD (baseline: 210 m; 3 months: 390 m; p = .001), MWD (baseline: 373 m; 3 months: 555 m; p = .002) and physical functioning score (SF-36) following SET, no increase in the mean daily PA level was found (395 ± 220 vs. 411 ± 228 METs/min; p = .43). Furthermore, the total number of steps and time spent in ambulatory activities did not change following SET. CONCLUSION: Three months of SET for IC leads to more patients meeting the ACSM/AHA public health minimum recommendations for PA. Assessment of PA could be incorporated as an outcome parameter in future research comparing different treatment modalities for peripheral arterial disease.

Physical activity monitoring in patients with peripheral arterial disease: validation of an activity monitor.

OBJECTIVES: The daily life physical activity (PA) of patients with peripheral arterial disease (PAD) may be severely hampered by intermittent claudication (IC). From a therapeutic, as well as research, point of view, it may be more relevant to determine improvement in PA as an outcome measure in IC. The aim of this study was to validate daily activities using a novel type of tri-axial accelerometer (Dynaport MoveMonitor) in patients with IC. METHODS: Patients with IC were studied during a hospital visit. Standard activities (locomotion, lying, sitting, standing, shuffling, number of steps and "not worn" detection) were video recorded and compared with activities scored by the MoveMonitor. Inter-rater reliability (expressed in intraclass correlation coefficients [ICC]), sensitivity, specificity, and positive predictive values (PPV) were calculated for each activity. RESULTS: Twenty-eight hours of video observation were analysed (n = 21). Our video annotation method (the gold standard method) appeared to be accurate for most postures (ICC > 0.97), except for shuffling (ICC = 0.38). The MoveMonitor showed a high sensitivity (>86%), specificity (>91%), and PPV (>88%) for locomotion, lying, sitting, and "not worn" detection. Moderate accuracy was found for standing (46%), while shuffling appeared to be undetectable (18%). A strong correlation was found between video recordings and the MoveMonitor with regard to the calculation of the "number of steps" (ICC = 0.90). CONCLUSIONS: The MoveMonitor provides accurate information on a diverse set of postures, daily activities, and number of steps in IC patients. However, the detection of low amplitude movements, such as shuffling and "sitting to standing" transfers, is a matter of concern. This tool is useful in assessing the role of PA as a novel, clinically relevant outcome parameter in IC.