Hennerici M G, Meairs S
Neurologische Universitätsklinik, Ruprecht-Karls-Universität Heidelberg, Klinikum Mannheim.
Nervenarzt. 1995 Dec;66(12):890-4; discussion 885.
Acetylsalicylic acid (ASS) is one of the best examined substances used in secondary prevention after TIA and stroke. Since different strategies and measurement variables were used in numerous randomised, double-blind, placebo-controlled studies (one end-variable, such as non-fatal stroke, myocardium infarction and vascular mortality, or combined end-variables, such as TIA, stroke and death), meta-analysis was necessary to prove that ASS resulted in about 22% reduction of secondary stroke. There is disagreement over the optimal dosage to prevent a stroke: earlier studies considered > or = 975 mg ASS per day, sometimes in combination with other substances, while more recently, lower dosages of about 300 mg per day or even as low as < or = 100 mg per day have been proposed. Higher and lower dosages were effective compared with placebo but with no significant difference in risk reduction, despite the trend towards a transient but insignificant reduction of secondary events for the high dosage. All available studies demonstrated a strictly dose-related gastro-intestinal hemorrhagic bleeding complication rate. Since no data are available from a direct comparison in a large sample size trial to prove the superiority of low-dose ASS (< or = 300 mg per day) over high dosages (> or = 975 mg per day) in secondary prevention of stroke, we believe that the lowest dosage of < or = 100 mg per day should be recommended for safety reasons.
乙酰水杨酸（ASS）是短暂性脑缺血发作（TIA）和中风后二级预防中研究最为充分的药物之一。由于众多随机、双盲、安慰剂对照研究采用了不同的策略和测量变量（一个终末变量，如非致死性中风、心肌梗死和血管性死亡，或联合终末变量，如TIA、中风和死亡），因此有必要进行荟萃分析以证明ASS可使二级中风发生率降低约22%。对于预防中风的最佳剂量存在分歧：早期研究认为每日ASS剂量≥975mg，有时还会联合其他药物，而最近有人提出每日剂量约300mg甚至低至≤100mg。与安慰剂相比，高剂量和低剂量均有效，但在降低风险方面无显著差异，尽管高剂量组二级事件有短暂但不显著的减少趋势。所有现有研究均表明胃肠道出血并发症发生率与剂量严格相关。由于尚无大样本量试验的直接比较数据来证明低剂量ASS（≤300mg/天）在中风二级预防中优于高剂量（≥975mg/天），出于安全考虑，我们认为应推荐每日最低剂量≤100mg。
