Risk vs benefit of anti-thrombotic therapy in ischaemic stroke patients with cerebral microbleeds.
BACKGROUND
Retrospective studies suggested that cerebral microbleeds (MB) on magnetic resonance images (MRI) increase risk of intracerebral haemorrhage (ICH).


OBJECTIVE
To compare the benefit of anti-thrombotic agents in stroke prevention (absolute risk reduction 2.49 -6 %) versus risk of ICH in ischaemic stroke patients with MB.


METHODS
We prospectively studied patients admitted consecutively for acute ischaemic stroke between 1999 and 2004. MB on MRI were documented. Primary end points were subsequent ICH, recurrent cerebral infarct (CI) and mortality.


RESULTS
A total of 908 patients were recruited. MB were identified in 252 (27.8 %) patients. Mean follow-up period was 26.6 +/- 15.4 months. Risk of subsequent ICH increased significantly with quantity of MB: 0.6 % (no MB), 1.9 % (1 MB), 4.6 % (2-4 MB) and 7.6 % (>or= 5 MB) (p < 0.001). There was also a significant increase in mortality from ICH: 0.6 %, 0.9 %, 1.5 % and 3.8 % respectively (p = 0.054). Rate of recurrent CI was 9.6 %, 5.6 %, 21.5 % and 15.2 % respectively (p = 0.226). Mortality from CI and myocardial infarction did not increased with quantity of MB. Survival analyses showed that age, presence of MB, mixed cortical-subcortical distribution of MB were independent predictors of subsequent ICH.


CONCLUSIONS
Risk and mortality of ICH increased with quantity of MB. As tendency to recurrent CI exceed that of ICH, anti-thrombotic agents are still warranted. However, in patients with >or= 5 MB, the high risk and mortality of ICH seem to outweigh the modest benefit of antithrombotic agents. Extra precautions should be taken to minimize risk of ICH. Further studies in patients on Coumadin and assessment of functional outcome are warranted to support these preliminary findings.
Soo
Yannie O Y
YO
Division of Neurology, Dept. of Medicine & Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, 30-32 Ngan Shing Street, Shatin, Hong Kong.
Yang
Song Ran
SR
Lam
Wynnie W M
WW
Wong
Adrian
A
Fan
Yu Hua
YH
Leung
Howan H W
HH
Chan
Anne Y Y
AY
Leung
Cecilia
C
Leung
Thomas W H
TW
Wong
Lawrence K S
LK
D001921:Brain / Q000098:blood supply / Q000473:pathology; D002545:Brain Ischemia / Q000188:drug therapy* / Q000473:pathology / Q000517:prevention & control*; D002543:Cerebral Hemorrhage / Q000139:chemically induced* / Q000401:mortality / Q000473:pathology; D005343:Fibrinolytic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000401:mortality; D012044:Regression Analysis; D012306:Risk; D020521:Stroke / Q000150:complications / Q000188:drug therapy* / Q000517:prevention & control*
D005343:Fibrinolytic Agents