Elevated serum lipoprotein(a) as a potential predictor for combined intracranial and extracranial artery stenosis in patients with ischemic stroke.

OBJECTIVES

Despite compelling evidence of lipoprotein(a) [Lp(a)] as a risk factor for ischemic stroke, its underlying mechanism remains unclear. Our aim is to investigate whether serum Lp(a) level is associated with the extent and location of cerebral steno-occlusive lesions, and with large artery atherosclerotic (LAA) stroke in Korean patients.

METHODS

We analyzed data prospectively collected over a 3-year period on consecutive patients with stroke or TIA. Based on an angiographic study, a total of 1012 patients were classified into four subtypes: non-cerebral stenosis (n=654), intracranial stenosis (n=198), extracranial carotid stenosis (n=86), and combined intracranial and extracranial carotid stenosis (n=74). Independent associations of Lp(a) levels with the extent and location of cerebral stenosis were evaluated, and Lp(a) levels of subtypes by the TOAST criteria were compared.

RESULTS

Lp(a) levels of LAA stroke were significantly higher than those of the other four stroke mechanisms. Patients with more advanced intracranial (p=0.001) and extracranial carotid stenoses (p=0.001) tended to have higher Lp(a) levels. In multiple regression analysis, the third Lp(a) quartile was the strongest risk factor for isolated intracranial (OR 3.36, 95% CI 1.77-6.37) or extracranial stenosis (OR 4.82, 95% CI 1.96-11.88), whereas the fourth Lp(a) quartile was the most powerful predictor for combined intracranial and extracranial carotid stenosis (OR 4.98, 95% CI 1.92-12.91).

CONCLUSIONS

Our results indicate that greatly elevated Lp(a) levels are associated with LAA stroke and extensive burden of cervicocerebral steno-occlusive lesions, which might offer indirect evidence of proatherothrombogenic role of Lp(a) in ischemic stroke.