Pentoxifylline and intermittent claudication: review of clinical trials and cost-effectiveness analyses

Intermittent claudication (IC) is common in the elderly; the prevalence is approximately 6% in 50- to 60-year-old patients and 10-20% in those over the age of 70. Several risk factors, especially smoking, are associated with increased prevalence. Disease progression results in increasingly debilitating and costly surgical intervention for about 20% of patients. This report reviews findings from some of the clinical studies that demonstrated the efficacy of pentoxifylline, the only U.S.-approved medical therapy for IC. Findings from a recently published cost-effectiveness analysis are presented. IC is difficult to study clinically because pain is both variable and subjective. In two multicenter, randomized, placebo-controlled studies, carefully monitored treadmill testing showed that pentoxifylline-treated patients had significantly improved walking distances even in the presence of a placebo effect. The pentoxifylline effect was pronounced in patients from a clinical target population defined by low baseline resting pressure ratios (< or =0.8) and long disease duration ( > 1 year). To understand the social implications of these findings, treadmill distances were converted to comparable distances on flat ground. Improvements on pentoxifylline therapy translate to walking distances that enable greater daily function. This improvement has significant practical benefit to the quality of life of IC patients. Using Medicare expenditure data, it was found that pentoxifylline therapy reduced average hospital costs per patients by $1,173. Direct medical cost savings of $69 to $3,090 were suggested by sensitivity analyses. In analyses of practical aspects of walking distance as well as cost-effectiveness analyses, pentoxifylline appears to be a highly useful treatment for IC.