Frågedatum: 1981-02-25
RELIS database 1981; id.nr. 2454, DRUGLINE
www.svelic.se
Utredningen som riktar sig till hälso- och sjukvårdspersonal, har utformats utefter tillgänglig litteratur och resurser vid tidpunkten för utredning. Innehållet i utredningen uppdateras inte. Hälso- och sjukvårdspersonal är ansvarig för hur de använder informationen vid rådgivning eller behandling av patienter.


Acetylsalicylsyra som terapi vid tromboser. Dokumentation önskas över acetylsalicylsyrans trombocyt



Fråga: Acetylsalicylsyra som terapi vid tromboser. Dokumentation önskas över acetylsalicylsyrans trombocytaggregationshämmande effekt.

Sammanfattning: Aspirin prevents platelet aggregation due to inhibition of prostaglandin synthesis. There is evidence for a limited prophylactic effect for thromboembolism in men. The optimum dosage schedule are not yet known.

Svar: The field of platelet aggregation and the use of ASA in the prevention of cerebral ischaemia especially transient ischaemic attacks of stroke is a highly controversial one. However, the following facts which led to the conclusion below have been gathered.

A multicenter trial in Canada that involved 587 patients over a 26 month period showed that aspirin is safe and effective for decreasing the risk of recurrent TIA or strokes in men who has TIA due to fibrin-platelet thrombi. There was no evidence for effect in women or in completed strokes in both sexes. The risk of recurrent TIA was decreased by 19 per cent and death by 31 per cent. Recommended daily dose was 1.3 g (1).

A similar multicenter trial involving 178 patients over a 24 month period in the USA by Fields et al did not show any statistically significant difference between ASA and placebo both in the surgical and medical groups (2,3).

Pacciovetti has shown that both low and high doses of ASA will prevent platelet aggregation (5). Harvey J Weiss also shows that there is evidence that aspirin prevents platelet aggregation by inhibition the synthesis of prostaglandin and thromboxane A2 (6).

Aaron J Maras went further to show that low doses of aspirin will inhibit cyclo-oxygenase the enzyme necessary for thromboxane A2 synthesis, and at high doses the synthesis of prostacycline (6,7).

Clinically William H Harris has showed that aspirin has proven to be of use in the prophylaxis of venous thrombosis after total hip replacement in men (8).

Harter et al showed the same property when applied to hemodialysis patients in low doses (9).

Lastly most TIA´s are probably caused by fibrin-platelet embolism at initial lesions (10).

Referenser: