RT Journal
A1 Snoep JD, Hovens MC, Eikenboom JJ, van der Bom JG, Huisman MV
T1 Association of laboratory-defined aspirin resistance with a higher risk of recurrent cardiovascular events: A systematic review and meta-analysis
JF Archives of Internal Medicine
JO Archives of Internal Medicine
YR 2007
FD August 13
VO 167
IS 15
SP 1593
OP 1599
DO 10.1001/archinte.167.15.1593
UL http://dx.doi.org/10.1001/archinte.167.15.1593
AB Background 
    The risk of recurrence of cardiovascular events among patients using aspirin (acetylsalicylic acid) for secondary prevention of such events remains high. Persistent platelet reactivity despite aspirin therapy, a laboratory-defined phenomenon called aspirin resistance (hereinafter, laboratory aspirin resistance), might explain this in part, but its actual contribution to the risk remains unclear. The objective of this study was to systematically review all available evidence on whether laboratory aspirin resistance is related to a higher risk of cardiovascular recurrent events.Methods 
    Using a predefined search strategy, we searched electronic databases. To be included in our analysis, articles had to report on patients who used aspirin for secondary cardiovascular prevention, had to contain a clear description of a method to establish the effects of aspirin on platelet reactivity, and had to report recurrence rates of cardiovascular events. Odds ratios of cardiovascular outcome of eligible studies were pooled in a random-effects model.Results 
    We included 15 full-text articles and 1 meeting abstract. Fifteen of these studies revealed an adverse association between laboratory aspirin resistance and occurrence of cardiovascular events. The pooled odds ratio of all cardiovascular outcomes was 3.8 (95% confidence interval, 2.3-6.1) for laboratory aspirin resistance.Conclusion 
    This systematic review and meta-analysis shows that patients biochemically identified as having laboratory aspirin resistance are more likely to also have “clinical resistance” to aspirin because they exhibit significantly higher risks of recurrent cardiovascular events compared with patients who are identified as (laboratory) aspirin sensitive.