Management of intermittent claudication with pentoxifylline: meta-analysis of randomized controlled trials

Abstract

OBJECTIVE: To evaluate the efficacy of pentoxifylline therapy in improving the walking capacity of patients with moderate intermittent claudication. DATA SOURCES: A search of MEDLINE for trials published between 1976 and 1994 inclusive, and a bibliographic review of all articles retrieved. STUDY SELECTION: Randomized, placebo-controlled, double-blind clinical trials were selected that evaluated the pain-free walking distance (the distanced walked on a treadmill before the onset of calf pain) and the absolute claudication distance (the maximum distance walked on a treadmill) among patients with moderate intermittent claudication. Twelve study groups in 11 trials were included in the analysis. DATA EXTRACTION: In addition to information regarding the trial design, patient characteristics, dosages and treatment periods, the means and standard deviations were collected for both the pain-free walking and absolute claudication distances. Trial quality was also assessed. DATA SYNTHESIS: Overall, there was a statistically significant improvement in the pain-free walking distance after pentoxifylline therapy (weighted mean difference 29.4 m [95% confidence interval (CI) 13.0 to 45.9 m]); this finding was based on a total sample of 612 patients (308 in the treatment groups and 304 in the control groups). A significant improvement was also noted in the absolute claudication distance (weighted mean difference 48.4 m [95% CI 18.3 to 78.6 m]); this was based on a total sample of 511 patients (258 in the treatment group and 253 in the control group). In a sensitivity analysis of the pain-free walking distance, significant treatment effects and no statistically significant heterogeneity were found when only trials were included that were "medically eligible" (involved patients with stage II disease and a pain-free walking distance of 50 to 200 m). In a similar sensitivity analysis of the absolute claudication distance, the two conditions resulting in a significant treatment effect and no significant heterogeneity were the inclusion of "medically eligible" trials and those with a shorter treatment duration (13 weeks or less). CONCLUSION: Pentoxifylline therapy may be efficacious in improving the walking capacity of patients with moderate intermittent claudication. However, properly conducted clinical trials are required to provide a true estimate of the benefit.