Brief Communication: Ramipril Markedly Improves Walking Ability in Patients with Peripheral Arterial Disease

Abstract

Peripheral arterial disease (PAD) affects up to 12% of adults older than 50 years of age. Conventional therapies have only modest effects in improving symptoms. To examine the effects of angiotensin-converting enzyme inhibition on walking ability in patients with PAD. Randomized, double-blind, placebo-controlled trial initiated in March 2003 and completed in January 2005. The Alfred Hospital, Melbourne, Australia. 40 older adults with symptomatic PAD and no history of diabetes or hypertension. 10 mg of ramipril (n = 20) or placebo (n = 20) once daily for 24 weeks. All patients completed the trial. Pain-free and maximum walking time were recorded during a standard treadmill test, and the standard Walking Impairment Questionnaire was administered. After adjustment for the baseline pain-free walking time, mean pain-free walking time after ramipril treatment was 227 seconds (95% CI, 175 seconds to 278 seconds; P < 0.001) longer than that after placebo treatment. Similarly, maximum walking time improved by 451 seconds in the ramipril group (CI, 367 seconds to 536 seconds; P < 0.001) but did not change in the placebo group. Ramipril improved the Walking Impairment Questionnaire median distance score from 5% (range, 1% to 39%) to 21% (range, 12% to 58%; P < 0.001), speed score from 3% (range, 3% to 39%) to 18% (range, 8% to 50%; P < 0.001), and stair-climbing score from 17% (range, 4% to 80%) to 67% (range, 38% to 88%; P < 0.001). No adverse events were reported. The sample size is modest, and the strict inclusion criteria limit the applicability of the results to patients with claudication and infrainguinal disease and those without diabetes. Ramipril improved pain-free and maximum walking time in some adults with symptomatic PAD.