title: [Aspirin dosage for prevention of cerebral infarct: arguments for low dosage].
abstract: 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.
authors.affiliation: Neurologische Universitätsklinik, Ruprecht-Karls-Universität Heidelberg, Klinikum Mannheim.
authors.forename: M G
authors.initials: MG
authors.lastname: Hennerici
authors.forename: S
authors.initials: S
authors.lastname: Meairs
mesh_terms: D001241:Aspirin / Q000008:administration & dosage* / Q000009:adverse effects; D002544:Cerebral Infarction / Q000517:prevention & control*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced; D006801:Humans; D002546:Ischemic Attack, Transient / Q000517:prevention & control*; D008297:Male; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D016032:Randomized Controlled Trials as Topic; D012008:Recurrence; D012307:Risk Factors
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin