Conservative drug treatment in patients with moderately severe chronic occlusive peripheral arterial disease. Scandinavian Study Group.

A double-blind, parallel group, multicenter clinical trial of pentoxifylline compared with placebo enrolled 150 patients with moderately severe chronic occlusive arterial disease (COAD) at three centers in Scandinavia. The study consisted of a 4-6 week single-blind, placebo-controlled run-in phase, during which the stabilization of the initial claudication distance of all patients was assessed before randomization to a 6-month double-blind observation period. The diagnosis of COAD was established by clinical findings, conventional angiography, and noninvasive peripheral Doppler pressure assessment at rest and after exercise. The results of the overall intention-to-treat analysis of the study population show statistically significant superiority of pentoxifylline over placebo for all absolute claudication distance summary and end point measures. By using two clinically relevant parameters, which are a resting ankle/arm pressure ratio 0.8 or less and a duration of COAD for greater than 1 year, a target population could be defined in whom trial results became highly significant. For nontarget patients with mild COAD, we conclude that basic therapeutic measures should include the treatment of risk factors and the initiation of physical training. For target patients, however, a multifactorial therapeutic approach, including the use of pentoxifylline, is justified.