Roxithromycin Treatment Prevents Progression of Peripheral Arterial Occlusive Disease in Chlamydia pneumoniae Seropositive Men: A Randomized, Double-Blind, Placebo-Controlled Trial

Background—Evidence has been provided that the atherosclerotic process may be associated with chronic infection with Chlamydia pneumoniae. The effect of antibiotic treatment on peripheral arterial occlusive disease has not been investigated yet. Methods and Results—Forty C pneumoniae seropositive men suffering from peripheral arterial occlusive disease were randomly assigned to receive either roxithromycin (300 mg daily) or placebo for 28 days. During the 2.7-year follow-up, the number of invasive revascularizations per patient, the walking distance before intervention (in patients without intervention at study end), and the change of carotid plaque size were assessed. Five interventions were performed on 4 patients (20%) in the roxithromycin group, and 29 interventions were performed on 9 patients (45%) in the placebo group. Limitation of walking distance to 200 m or less was observed in 4 patients (20%) in the roxithromycin group and in 13 patients (65%) in the placebo group. The effect of macrolide treatment on the number of interventions per patient and on preinterventional walking distance was significant. Possible confounding variables such as classical vascular risk factors were excluded by multiple regression analyses. Carotid plaque areas monitored over 6 months decreased in the roxithromycin group (mean relative value, 94.4%) but remained constant in the placebo group (100.2%). Regression of carotid plaque size observed in roxithromycin-treated patients was significant for soft plaques. Conclusions—This study indicates that macrolide treatment for 1 month is effective in preventing C pneumoniae seropositive men from progression of lower limb atherosclerosis for several years.