Outcome in patients with symptomatic occlusion of the internal carotid artery or intracranial arterial lesions: A meta-analysis of the role of baseline characteristics and type of antithrombotic treatment

Objectives: We performed a systematic review of the literature to assess the impact of potential risk factors of recurrent stroke other than a compromised cerebral blood flow in patients with carotid occlusion or intracranial arterial lesions. In addition, we investigated the effect of treatment with aspirin or oral anticoagulation on recurrent stroke rate and assessed whether the incidence of recurrent stroke has decreased over the years. Methods:We searched Medline (1966 and onwards) and reference lists of identified articles for papers reporting on the recurrent stroke risk in patients with carotid occlusion or intracranial arterial lesions. Two authors independently extracted information from all papers. The influence of study characteristics on the risk of the endpoints 'recurrent stroke', 'ipsilateral stroke' and 'vascular death' was determined by Poisson regression analysis. Rate ratios were calculated per 10 percentage points increase of a characteristic. Results and Conclusions: Patients with intracranial carotid stenosis or occlusion had a higher rate of recurrent stroke (rate ratio 1.09; 95% Cl 1.05-1.14) than patients with extracranial carotid occlusion or middle cerebral artery stenosis or occlusion. In patients with bilateral carotid occlusion the rate was lower (rate ratio 0.82; 95% Cl 0.68-0.98). No other vascular risk factors than hypertension (rate ratio 1.23; 95% CI 1.07-1.41) could be shown to increase the rate of recurrent stroke. Oral anticoagulation but not aspirin had a protective effect on the incidence of recurrent stroke (rate ratio 0.86; 95% CI 0.79-0.93). The reported rates of recurrent stroke in patients with symptomatic occlusion of the internal carotid artery or intracranial arterial lesions have not decreased over the years. Copyright (C) 2001 S. Karger AG, Basel.