Antiplatelet therapy and the outcome of subjects with intracranial injury: the Italian SIMEU study.

introductionPre-injury antithrombotic therapy might influence the outcome of subjects with head injuries and positive computed tomography (CT) scans. We aimed to determine the potential risk of pre-injury antiplatelet drug use on short- and long-term outcome of head injured subjects admitted to emergency departments (EDs) in Italy for extended observation.

methodsA total of 1,558 adult subjects with mild, moderate and severe head injury admitted to Italian EDs were studied. In multivariable logistic regression analyses, the short-term outcome was assessed by an evaluation of head CT scan at 6 to 24 hours after trauma and the long-term outcome by the Glasgow outcome scale (GOS) at six months.

resultsHead CT scan comparisons showed that 201 subjects (12.9%) worsened. The risk of worsening was increased two fold by the use of antiplatelet drugs (106, 19.7% treated versus 95, 9.3% untreated; relative risk (RR) 2.09, 95% CI 1.63 to 2.71). The risk was particularly high in subjects on clopidogrel (RR 5.76, 95% CI 3.88 to 8.54), independent of the association with aspirin. By logistic regression, 5 of 14 items were independently associated with worsening (Glasgow coma scale (GCS), Marshall category, antiplatelet therapy, intraventricular hemorrhage, number of lesions). After six months, only 4 of 14 items were predictors of unfavorable outcome (GOS 1 to 3) (GCS score, Marshall category, age in decades, intracerebral hemorrhage/contusion). The risk increased by 50% in the group treated with antiplatelet therapy (RR 1.58, 95% CI 1.28 to 1.95; P<0.001).

conclusionsAntithrombotic therapy (in particular clopidogrel) is a risk factor for both short-term and long-term unfavorable outcome in subjects with head injury, increasing the risk of progression and death, permanent vegetative state and severe disability.