CLEVER: Supervised exercise bests stenting, home care in patients with aortoiliac disease

AHA Scientific Sessions 2011

ORLANDO, Fla. — Walking ability in patients with symptom-limiting claudication improved best when supervised treadmill exercise was added to standard therapy, as compared with stenting alone, according to new data from the CLEVER study.

“In the past,have included a primary role for supervised exercise, as well as placement of stents and claudication medications. Nevertheless, invasive stent procedures, the most commonly used and expensive current therapy, has not been shown to offer better outcomes for patients with claudication and exercise performed in a supervised setting alone,” Alan T. Hirsh, MD, director of vascular medicine, Lillehei Heart Institute of University of Minnesota, said during his presentation of the Claudication: Exercise vs. Endoluminal Revascularization (CLEVER) study.

Researchers randomly assigned 111 patients (mean age, 64 years; 61% men) with aortoiliac peripheral artery disease into three treatment groups:

• Cilostazol (Pletal, Otsuka Pharmaceuticals) with home exercise (optimal medical care group);
• Optimal medical care plus supervised exercise for 6 months (supervised exercise group); or
• Optimal medical care plus primary stent revascularization (stent revascularization group).

Change in peak walking times vs. baseline times were assessed as the primary endpoint, while secondary endpoints included free-living step activity, quality of life and biomarkers of CVD risk. All treatments were successfully delivered. Compliance with cilostazol use was .90%. All stent procedures were successful and there was no clinically evidence restenosis at 6 months. Exercise compliance was also .71%. There were no treatment assignment crossovers, according to Hirsch.

At 6-month follow-up, the supervised exercise group experienced the greatest change in peak walking time with an improvement of 5.8 minutes from baseline. The stent revascularization group had intermediate change (3.7 minutes), and the optimal medical care group had the least change (1.2 minutes). Quality of life scores, assessed by the Walking Impairment Questionnaire and Peripheral Artery Questionnaire, also showed greater improvement in the supervised exercise and stent revascularization groups vs. optimal medical care (P=.03 and P<.001).

Alan T. Hirsch

Ankle-brachial index measurements were not significant when compared with baseline in the optimal medical care and supervised exercise groups, but resting ankle-brachial index improved by 0.29 in the stent revascularization group (P<.001). Both the supervised exercise and stent revascularization groups showed improvement in claudication onset time vs. optimal medical care at 6 months (P=.003 and P=.006).

Compared with supervised exercise or optimal medical care alone, change in free-living step activity had the greatest trend toward improvement in the stent revascularization group vs. optimal medical care and supervised exercise (114.3 vs. -5.6 and 72.6).

“Very simply, among patients with moderate to severe claudication and significant aortoiliac disease, supervised exercise offers better treadmill walking performance than stent revascularization alone, and both are superior to home care,” Hirsh said. “We do note that these are both quality of life interventions and stenting was associated with major improvements in quality of life.” He said this is a “great study outcome” for all patients, all physicians who care for peripheral arterial disease and for health systems. “CLEVER demonstrates a method of evaluation of relevant treatment choices that can inform patients and physicians now, but should also alter how future PAD clinical trials are designed.”

These results represent 6-month follow-up. An 18-month follow-up is still underway. – by Casey Murphy

For more information:

• Hirsh A. LBCT.05. Presented at: the American Heart Association Scientific Sessions 2011; Nov. 12-16, 2011; Orlando, Fla.
• Murphy T. Circulation. 2011;doi:10.1161/CIRCULATIONAHA.111.075770.

Disclosure: Dr. Hirsh has received research grant support from Abbott Vascular, Cytokinetics and Viromed, and consultant fees from AstraZeneca, Merck, Novartis and Pozen.

The apparent discordance between the treadmill outcome and quality of life further limit the trial’s potential impact on practice, and we await longer-term data for the durability of benefits. Unfortunately, this is unlikely to influence practice unless policies change. At this point in time, with all the evidence we have to date, it’s striking that reimbursement for supervised exercise is still not available for Medicare beneficiaries, which are most of the patients with PAD. In contrast, reimbursement for stenting is significant to providers and has not been linked to outcomes and both providers and industry are incentivized to provide invasive treatments.

Michael S. Conte, MD
Professor of Surgery
University of California

Disclosure: Dr. Conte reports no relevant financial disclosures.

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