Effect of intermittent pneumatic compression of foot and calf on walking distance, hemodynamics, and quality of life in patients with arterial claudication: a prospective randomized controlled study with 1-year follow-up

Abstract

Summary background data: Perioperative mortality, graft failure, and angioplasty limitations militate against active intervention for claudication. With the exception of exercise programs, conservative treatments yield modest results. Intermittent pneumatic compression [IPC] of the foot used daily for 3 months enhances the walking ability and pressure indices of claudicants. Although IPC applied to the foot and calf together [IPCfoot+calf] is hemodynamically superior to IPC of the foot, its clinical effects in claudicants remain undetermined.

Objective: This prospective randomized controlled study evaluates the effects of IPCfoot+calf on the walking ability, peripheral hemodynamics, and quality of life [QOL] in patients with arterial claudication.

Methods: Forty-one stable claudicants, meeting stringent inclusion and exclusion criteria, were randomized to receive either IPCfoot+calf and aspirin[75 mg] (Group 1; n = 20), or aspirin[75 mg] alone (Group 2; n = 21), with stratification for diabetes and smoking. Groups matched for age, sex, initial [ICD] and absolute [ACD] claudication distances, pressure indices [ABI], popliteal artery flow, and QOL with the short-form 36 Health Survey Questionnaire (SF-36). IPCfoot+calf (120 mm Hg, inflation 4 seconds x 3 impulses per minute, calf inflate delay 1 second) was used for 5 months, > or =2.5 hours daily. Both groups were advised to exercise unsupervised. Evaluation of patients, after randomization, included the ICD and ACD, ABI, popliteal artery flow with duplex and QOL* at baseline*, 1/12, 2/12, 3/12, 4/12, 5/12* and 17/12. Logbooks allowed compliance control. Wilcoxon and Mann-Whitney corrected[Bonferroni] tests were used.

Results: At 5/12 median ICD, ACD, resting and postexercise ABI had increased by 197%, 212%, 17%, and 64%, respectively, in Group 1 (P < 0.001), but had changed little (P > 0.1) in Group 2; Group 1 had better ICD, ACD, and resting and postexercise ABI (P < 0.01) than Group 2. Inter- and intragroup popliteal flow differences at 5/12 were small (P > 0.1). QOL had improved significantly in Group 1 but not in Group 2; QOL in the former was better (P < 0.01) than in Group 2. QOL in Group 1 was better (P < 0.01) than in Group 2 at 5/12. IPC was complication free. IPC compliance (> or =2.5 hours/d) was >82% at 1 month and >85% at 3 and 5 months. ABI and walking benefits in Group 1 were maintained a year after cessation of IPC treatment.

Conclusions: IPCfoot+calf emerged as an effective, high-compliance, complication-free method for improving the walking ability and pressure indices in stable claudication, with a durable outcome. These changes were associated with a significant improvement in all aspects of QOL evaluated with the SF-36. Despite some limited benefit noted in some individuals, unsupervised exercise had a nonsignificant impact overall.

FIGURE 1. Initial claudication distance (ICD) (median and interquartile range) in Groups 1 (IPC_foot+calf) and 2 (control). The increments of ICD gained by those on IPC_foot+calf in the consecutive study sessions were all statistically significant (P < 0.006*) until the third month. Changes in the control patients were not significant. Those on IPC_foot+calf performed better than the controls as early as the third month (P = 0.005); ICD in Group 1 was also better (P = 0.0002) on the fifth month. At 12 months’ follow-up, the ICD in Group 1 did not differ (P = 0.57*) from that at the fifth month (*Bonferroni correction).

FIGURE 2. Absolute claudication distance (ACD) (median and interquartile range) in Groups 1 (IPC_foot+calf) and 2 (control). The ICD improvements of those on IPC_foot+calf in the consecutive study sessions were significant (P < 0.01*) until the fourth month. Changes in the control patients were not significant. Group 1 had a better ACD than the controls as early as the second month (P = 0.01); the difference was also significant (P = 0.0002) at 5 months. At 12 months’ follow-up, the ACD in Group 1 did not differ from that at 5 months (P = 0.75*) (*Bonferroni correction).

FIGURE 3. Resting ankle brachial index (r-ABI) (median and interquartile range) in Groups 1 (IPC_foot+calf) and 2 (control). The r-ABI improvements of those on IPC_foot+calf in the first and second month were both significant (P < 0.005*). Changes in the control patients were not significant. Group 1 had a better r-ABI than the controls in the third month (P = 0.0127); this also applied in the fifth month (P = 0.03). At 12 months’ follow-up, the r-ABI in Group 1 was not different (P = 0.2*) from that at 5 months (*Bonferroni correction).

FIGURE 4. Postexercise ankle brachial index (p-eABI) in Groups 1 (IPC_foot+calf) and 2 (control). Increases in the p-eABI over the first and second months among those on IPC_foot+calf were both significant (P < 0.01*). Changes in the control patients were not significant. Group 1 had a higher p-eABI than Group 2 (P = 0.04) as early as the second month; this also applied on the fifth month (P = 0.0026). At 12 months’ follow-up, the p-eABI in Group 1 was not different statistically from that at 5 months (P = 0.45*) (*Bonferroni correction).

FIGURE 5. Popliteal artery volume flow (median and interquartile range) in Groups 1 (IPC_foot+calf) and 2 (control). Differences within and between groups were not statistically significant.

FIGURE 6. Perception of physical functioning, role physical, bodily pain, and general health (A), and perception of vitality, social functioning, emotional role, and mental health (B), evaluated with the SF-36 health survey questionnaire in Groups 1 (IPC_foot+calf) (shaded bars) and 2 (control) (white bars), at baseline (left), and at 5 months (right). Performance in all these domains of quality of life increased significantly (P < 0.001) within 5 months of treatment with IPC_foot+calf. Changes in the control patients were not statistically significant. Although differences were small (P > 0.1) at baseline, Group 1 was better than the controls at 5 months (P < 0.01) in all these domains.