Aspirin -- just for men?
First it was an apple, now it is an aspirin a day that may keep the doctor away. Aspirin has become standard for heart attack prevention, but research published in the online open access journal BMC Medicine suggests that this may really be a man's drug.
Scientists have long puzzled over why the protective effects of aspirin vary so widely between clinical trials. Some trials show no difference between aspirin and placebo, whilst others report that aspirin reduces the risk of a heart attack by more than 50%.
This latest study, from The James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, highlights the influence of gender on aspirin's protective powers. Investigators examined the results of 23 previously published clinical trials for the effect for aspirin in heart attack prevention, involving more than 113,000 patients. The authors then analysed how much the ratio of men to women in these trials affected the trials' outcomes.
"Trials that recruited predominantly men demonstrated the largest risk reduction in non-fatal heart attacks," says Dr Don Sin, one of the study's authors. "The trials that contained predominately women failed to demonstrate a significant risk reduction in these non-fatal events. We found that a lot of the variability in these trials seems to be due to the gender ratios, supporting the theory that women may be less responsive to aspirin than men for heart protection."
The mechanisms of this resistance are not yet understood, although recent studies have shown that men and women have major differences in the structure and physiology of the heart's blood vessels.
"From our findings we would caution clinicians on the prescribing aspirin to women, especially for primary prevention of heart attacks," says Dr Sin. "Whether or not other pharmaceutical products would be more effective for women is unclear; more sex-specific studies should now be conducted."
Source: BioMed Central
译文：
阿司匹林已经成为预防心脏病的常用药物，但最近发表在在线版《BMC医学》（BMC Medicine）上的文章表示，阿司匹林可能是适合男性使用的药物。
科学家一直对阿司匹林在临床实验中表现出来效果的巨大差异感到困惑。其中一些实验显示，在阿司匹林和安慰剂之间没有差异，而另一些则认为阿司匹林能使发生心脏病的风险降低50%以上。
在最新研究中，来自The James Hogg iCAPTURE心血管和肺部研究中心的科学家发现性别对阿司匹林的这些保护作用有影响。科学家分析了之前发表的23项关于阿司匹林对预防心脏病的临床实验结果，其中包括了超过113000位病人。作者接着研究了这些测试中男女比例对最终结果的影响。
文章作者Don Sin博士表示：“那些以男性为主的实验表明阿司匹林对于降低非致死性心脏病的发生有很大效果，而以女性为主的研究证明没有明显作用。我们发现这些实验结果的多样性似乎是性别比例引起的，这证实了女性对阿司匹林的反应没有男性明显。”
以上现象的内在机制并不清楚，尽管最近的研究发现男性和女性在心血管的结构和生理方面存在很大差异。Sin说：“我们认为医生需要注意开给女性的阿司匹林处方，特别是那些为了预防心脏病的处方。而是否存在其它对女性更有效的药物尚不清楚，我们还需要进行更多性别相关的测试。”（刘乐译自physorg）
