Apo(a) size in ischemic stroke: relation with subtype and severity on hospital admission

To determine the distribution of apolipoprotein (a) (apo[a]) isoforms and their relation to the clinical severity of different ischemic stroke subtypes.

Ninety-four hospital cases with a first-ever ischemic stroke and 188 randomly selected control subjects matched for age, gender, and ethnicity were enrolled. Stroke etiology was defined according to Trial of Org 10172 in Acute Stroke Treatment criteria. NIH Stroke Scale (NIHSS) was used to assess the severity of stroke on admission.

In univariate analysis, the presence of at least one small apo(a) isoform was associated with ischemic stroke in men (p = 0.02) but not in women (p = 0.33). After allowance for age, gender and traditional vascular risk factors, subjects carrying at least one small apo(a) isoform were at increased risk of atherothrombotic stroke (odds ratio [OR] 7.1, 95% CI 2.8 to 17.5, p = 0.00001) but not of lacunar infarction (OR 1.1, 95% CI 0.5 to 2.7, p = 0.78). Multivariate logistic regression analysis revealed that in the atherothrombotic stroke group, the presence of at least one small-sized apo(a) phenotype was associated with an NIHSS score > or =6 (OR 13.6, 95% CI 1.6 to 111.9, p = 0.015).

Small apolipoprotein (a) isoforms distinguish atherothrombotic stroke from lacunar infarction and are associated with the severity of atherothrombotic stroke.