I congratulate Dr Sarasin and his colleagues for their detailed cost-effectiveness analysis of antiplatelet therapy in cerebrovascular disease.1 They conclude that the combination of aspirin and dipyridamole is "more effective and less costly than aspirin alone." However, this conclusion hinges on 2 key assumptions that are flawed, particularly for medical care in the United States.
The authors estimated the daily costs for aspirin, clopidogrel, and the aspirin/dipyridamole combination at $0.02, $2.40, and $0.60, respectively. In the sensitivity analysis, the highest daily cost considered for aspirin/dipyridamole was $1.20. While this cost may be appropriate for the aspirin/dipyridamole combination available in Europe, it is a significant underestimate for the United States. In the United States, based on a 30-day pricing period, the average wholesale price for aspirin/dipyridamole is $2.95 per day, only slightly lower than that of clopidogrel ($3.21 per day) (oral communication with Boehringer Ingleheim Pharmaceuticals, Inc, Ridgefield, Conn, and Bristol-Myers Squibb Company, New York, NY; December 19, 2000). The higher US price for aspirin/dipyridamole treatment overwhelms any potential cost savings arising from its greater stroke prevention compared with aspirin alone.