@article {6297, title = {Multilocus genetic risk score associates with ischemic stroke in case-control and prospective cohort studies.}, journal = {Stroke}, volume = {45}, year = {2014}, month = {2014 Feb}, pages = {394-402}, abstract = {

BACKGROUND AND PURPOSE: Genome-wide association studies have revealed multiple common variants associated with known risk factors for ischemic stroke (IS). However, their aggregate effect on risk is uncertain. We aimed to generate a multilocus genetic risk score (GRS) for IS based on genome-wide association studies data from clinical-based samples and to establish its external validity in prospective population-based cohorts.

METHODS: Three thousand five hundred forty-eight clinic-based IS cases and 6399 controls from the Wellcome Trust Case Control Consortium 2 were used for derivation of the GRS. Subjects from the METASTROKE consortium served as a replication sample. The validation sample consisted of 22 751 participants from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium. We selected variants that had reached genome-wide significance in previous association studies on established risk factors for IS.

RESULTS: A combined GRS for atrial fibrillation, coronary artery disease, hypertension, and systolic blood pressure significantly associated with IS both in the case-control samples and in the prospective population-based studies. Subjects in the top quintile of the combined GRS had >2-fold increased risk of IS compared with subjects in the lowest quintile. Addition of the combined GRS to a simple model based on sex significantly improved the prediction of IS in the combined clinic-based samples but not in the population-based studies, and there was no significant improvement in net reclassification.

CONCLUSIONS: A multilocus GRS based on common variants for established cardiovascular risk factors was significantly associated with IS both in clinic-based samples and in the general population. However, the improvement in clinical risk prediction was found to be small.

}, keywords = {Adult, Aged, Aged, 80 and over, Atrial Fibrillation, Blood Pressure, Brain Ischemia, Case-Control Studies, Cohort Studies, Coronary Artery Disease, Female, Genetic Predisposition to Disease, Genetic Variation, Genome-Wide Association Study, Humans, Hypertension, Male, Middle Aged, Multilocus Sequence Typing, Polymorphism, Single Nucleotide, Population, Prospective Studies, Reproducibility of Results, Risk Assessment, Risk Factors, Sex Factors, Stroke}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.113.002938}, author = {Malik, Rainer and Bevan, Steve and Nalls, Michael A and Holliday, Elizabeth G and Devan, William J and Cheng, Yu-Ching and Ibrahim-Verbaas, Carla A and Verhaaren, Benjamin F J and Bis, Joshua C and Joon, Aron Y and de Stefano, Anita L and Fornage, Myriam and Psaty, Bruce M and Ikram, M Arfan and Launer, Lenore J and van Duijn, Cornelia M and Sharma, Pankaj and Mitchell, Braxton D and Rosand, Jonathan and Meschia, James F and Levi, Christopher and Rothwell, Peter M and Sudlow, Cathie and Markus, Hugh S and Seshadri, Sudha and Dichgans, Martin} }