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ORLANDO -- Compared with usual care for moderate to severe claudication, walking improved most with supervised exercise, but stenting won more quality-of-life points, researchers from the CLEVER trial found.

The change from baseline in the peak walking time (the primary endpoint) at six months in the supervised exercise group was 4.6 minutes (P<0.001) and 2.5 minutes for those in the stenting group (P=0.02), compared with medical therapy alone, Alan T. Hirsch, MD, from the University of Minnesota Medical School in Minneapolis, and colleagues reported.

The difference in claudication onset time (a secondary endpoint) compared with usual care was 2.2 minutes for supervised exercise (P<0.003) and 2.9 minutes for stenting (P=0.006), according to their presentation at the American Heart Association meeting here.

The study was published simultaneously online in Circulation: Journal of the American Heart Association.

In CLEVER (CLaudication: Exercise Vs Endoluminal Revascularization Study), a randomized controlled trial, "we have learned that optimal medical care has little clinical benefit, with less than expected improvement," study discussant Michael S. Conte, MD, from the University of California in San Francisco, said during a press conference.

He noted that stenting is incentivized by favorable reimbursement, while supervised exercise is not. In fact, Conte said that the results of this trial are unlikely to change clinical practice unless there is a change in reimbursement policy.

Peripheral artery disease affects millions of people worldwide, and about eight million in the U.S. alone, of which two million have claudication. Stenting peripheral arteries has increased in recent years despite a paucity of evidence to support it, Conte said.

Physicians treat claudication with either supervised exercise, medications, or angioplasty and stenting, but the relative effectiveness of each type of treatment has been unclear, Hirsch said.

To help better define the evidence, he and his colleagues randomized 111 patients with aortoiliac peripheral artery disease to receive one of three treatments: optimal medical care (OMC), OMC plus supervised exercise (three times a week for 78 weeks), and OMC plus stenting.

All three groups received cilostazol, which improves blood flow to the legs.

The study is the first multicenter randomized controlled trial to compare these three treatments and the first trial conducted exclusively in patients with aortoiliac PAD, "long considered ideal for stent revascularization," Hirsch said.

The average age of participants was 64, 61% were men, and 80% were white. Participants were recruited from 29 centers in the U.S. More than half smoked, and nearly one-fourth had diabetes.

At baseline, the patients could walk for only about five minutes. None had evidence of critical ischemia, and there were more patients with distal disease, "which reflects community practice," Hirsch added.

The OMC and stent groups were well matched, but there were more people in the exercise group who had had a prior stroke (P=0.007); however, it was not associated with walking impairment, Hirsch said.

He noted that for all three groups, the average ankle-brachial index (ABI) was 68%.

As noted, the two active treatment arms "dwarfed" the optimal medical group in the primary endpoint, as well as in claudication onset time.

Another secondary endpoint, community walking, also favored the two treatment arms. Compared with OMC, exercise and stenting produced a difference of 78 steps and 120 steps, respectively (P=0.06 and P=0.10).

Quality-of-life scores improved with both active treatments, but it was greater in the stenting arm.

Compared with OMC, the quality-of-life scores in the supervised exercise and stenting groups were 17.4 and 30.4, respectively. The difference was significant for stenting, as well as for the difference between stenting and supervised exercise (P=0.001 for both).

Hirsch said there are many complex reasons for the higher quality-of-life scores for stenting but these are beyond the scope of this study. Results at 18 months should provide "valuable additional data."

Stenting also scored significantly higher in physical and social limitation measures. Interestingly, only those in the stenting arm had a significant change in resting ABI from baseline (0.29, P<0.0001).

In his discussion, Conte asked if treadmill performance is the best measure for comparing effectiveness of intermittent treatment strategies. He noted that a "training" effect in treadmill-based supervised exercise is inherent and that it needs correlation with function in daily life.

Indeed, in the study, the improvements seen in treadmill measures of function status were not seen in the community-walking test, which is consistent with other studies. "It is possible that improved leg function may, even with an associated improvement in claudication symptoms, not consistently lead to an increase in a patient's ambulatory behavior," the CLEVER investigators surmised.

However, at six months, both supervised exercise and stenting proved better than OMC, which increases the options available for this growing population, they concluded.

"We need greater investment in these types of studies and we need to increase pressure on CMS [Centers for Medicare and Medicaid Services] to reimburse for supervised exercise," Hirsch concluded.