Abaci Adnan, Caliskan Mustafa, Bayram Fahri, Yilmaz Yucel, Cetin Mustafa, Unal Ali, Cetin Servet
Department of Cardiology, Gazi University School of Medicine, Ankara, Turkey.
Platelets. 2006 Feb;17(1):7-13. doi: 10.1080/09537100500163358.
Aspirin non-responsiveness has been described as having a normal closure time (CT) by platelet function analyzer (PFA)-100 assay despite confirmed treatment with aspirin. There is no standard definition of aspirin non-responsiveness by PFA-100, with a variety of cut-off values having been used. We proposed an alternative definition of aspirin non-responsiveness by PFA-100 assay.
One hundred eighty-four patients with diagnosis of stable coronary artery disease or diabetes mellitus were included in the study. Blood samples were drawn before and after the 7 days of aspirin therapy. An individual was labelled as aspirin non-responder if his/her post-aspirin CT was not 2SD above his/her baseline CT, where SD was calculated from the baseline CTs of the study population. Aspirin non-responsiveness was also defined as having a normal post-aspirin CT (< or =193 s) regardless of pre-aspirin CT.
The baseline CT ranged 82-187 s (mean 129.1 +/- 27.5, median 128 s) in the study population. At the end of 1 week of aspirin administration, CT increased to a mean of 260.7 +/- 63.6 s (range 102-301). According to our definition, 28 (15.2%) of 184 patients were aspirin non-responders. Univariate analysis indicated that aspirin non-responsiveness was closely associated with gender (P = 0.012) diabetes (P = 0.006), smoking (P = 0.0496) and hypertension (P = 0.021). Multivariate analysis identified diabetes (P = 0.016) as the only significant independent predictor for the presence of aspirin non-responsiveness. Thirty-four of 184 patients (18.5%) classified as aspirin non-responders according to the second criteria. Seven patients with prolongation of post-aspirin CT more than 2SD were classified as aspirin non-responders by the second criteria. Only 1 patient without prolongation of CT more than 2SD was classified as aspirin responsive by the second criteria.
Definition of aspirin non-responsiveness as post-aspirin CTs < or =193 s might overestimate the prevalence of aspirin non-responsiveness. Nevertheless, definition of aspirin non-responsiveness by PFA-100 must be standardized and its utility as a predictor of cardiovascular events needs to be further investigated.
阿司匹林无反应性被描述为尽管已确诊接受阿司匹林治疗，但血小板功能分析仪（PFA）-100检测的封闭时间（CT）正常。PFA-100对阿司匹林无反应性尚无标准定义，已使用了多种临界值。我们提出了一种通过PFA-100检测定义阿司匹林无反应性的替代方法。
本研究纳入了184例诊断为稳定型冠状动脉疾病或糖尿病的患者。在阿司匹林治疗7天前后采集血样。如果个体阿司匹林治疗后的CT值未比其基线CT值高出2个标准差（SD），则将其标记为阿司匹林无反应者，其中SD是根据研究人群的基线CT值计算得出的。阿司匹林无反应性也被定义为无论阿司匹林治疗前的CT值如何，阿司匹林治疗后的CT值正常（≤193秒）。
研究人群的基线CT值范围为82 - 187秒（平均129.1±27.5，中位数128秒）。在阿司匹林给药1周结束时，CT值增加到平均260.7±63.6秒（范围102 - 301）。根据我们的定义，184例患者中有28例（15.2%）为阿司匹林无反应者。单因素分析表明，阿司匹林无反应性与性别（P = 0.012）、糖尿病（P = 0.006）、吸烟（P = 0.0496）和高血压（P = 0.021）密切相关。多因素分析确定糖尿病（P = 0.016）是阿司匹林无反应性存在的唯一显著独立预测因素。根据第二个标准，184例患者中有34例（18.5%）被归类为阿司匹林无反应者。7例阿司匹林治疗后CT延长超过2个标准差的患者根据第二个标准被归类为阿司匹林无反应者。根据第二个标准，只有1例CT未延长超过2个标准差的患者被归类为阿司匹林反应者。
将阿司匹林无反应性定义为阿司匹林治疗后的CT值≤193秒可能高估了阿司匹林无反应性的患病率。然而，PFA-100对阿司匹林无反应性的定义必须标准化，其作为心血管事件预测指标的效用需要进一步研究。
