A Model of Cost-effectiveness of Tissue Plasminogen Activator in Patient Subgroups 3 to 4.5 Hours After Onset of Acute Ischemic Stroke

Study objective The European Cooperative Acute Stroke Study III (ECASS III) showed that recombinant tissue plasminogen activator (rtPA) administered 3 to 4.5 hours after acute ischemic stroke led to improvement in patient disability versus placebo. We evaluate the long-term incremental cost-effectiveness of rtPA administered 3 to 4.5 hours after acute ischemic stroke onset versus no treatment according to patient clinical and demographic factors. Methods We developed a disease-based decision analytic model to project lifetime outcomes of patients post–acute ischemic stroke from the payer perspective. Clinical data were derived from the ECASS III trial, longitudinal cohort studies, and health state preference studies. Cost data were based on Medicare reimbursement and other published sources. We performed probabilistic sensitivity analyses to evaluate uncertainty in the analysis. Results rtPA in a hypothetical cohort resulted in a gain of 0.07 years of life (95% credible range 0.0005 to 0.17) and 0.24 quality-adjusted life-years (95% credible range 0.01 to 0.60) and a difference in cost of $1,495 (95% credible range –$4,637 to $6,100) compared with placebo. The incremental cost-effectiveness ratio for all patients was $6,255 per quality-adjusted life-year gained; for patients younger than 65 years, cost saving; for patients aged 65 years or older, $35,813 per quality-adjusted life-year; for patients with baseline National Institutes of Health Stroke Scale (NIHSS) score 0 to 9, $16,322 per quality-adjusted life-year; for patients with NIHSS score 10 to 19, $37,462 per quality-adjusted life-year; and for patients with NIHSS score greater than or equal to 20, $2,432 per quality-adjusted life-year. The majority of other subgroups such as sex, history of stroke, and history of hypertension were either cost saving or cost-effective, with the exceptions of diabetes and atrial fibrillation. Conclusion The results indicate that rtPA in the 3- to 4.5-hour therapeutic window provides improvement in long-term patient outcomes in most patient subgroups and is a good economic value versus no treatment.