MedicalResearch.com: What are the main findings of this study?
Dr. Ikram: We show that the risk of stroke might be increased due to an increased risk of ischemic stroke or increased risk of hemorrhagic stroke. Because these subtypes of stroke require different -often opposite- clinical management, currently available prediction rules for any stroke are insufficient. We propose a novel prediction rule that provides separate risks for ischemic stroke and hemorrhagic stroke.
MedicalResearch.com: Were any of the findings surprising?
Dr. Ikram: We show that an increased risk of ischemic stroke stroke does not parallel an increased risk of hemorrhagic stroke. In other words, there is a subgroup of persons that specifically has an increased risk of hemorrhagic stroke and not ischemic stroke, and vice versa. These different subgroups may therefore require different clinical management. Ischemic strokes occur due to insufficient blood supply to parts of the brain; these strokes require opening the obstructed artery to re-establish blood flow. In contrast, hemorrhagic strokes occur due to leakage of blood through blood vessels into the brain; these strokes require stopping the bleeding.
MedicalResearch.com: What should patients and clinicians take away from this report?
Dr. Ikram: An increased risk of stroke can be either due to ischemic stroke or hemorrhagic stroke, and these two risks should be assessed differently.
MedicalResearch.com: What further research do you recommend as a result of this study?
Dr. Ikram: Future studies can focus on several points.
First, they can investigate whether this prediction rule can be further refined by using additional clinical information, e.g. APOE-genotype, medication use etc.
Second, studies should investigate to what extent the clinical management between the subgroups should indeed differ. Finally, a further refinement of subgroups can be made, for instance studying subtypes of ischemic stroke (small vessel, large vessel, cardioembolic) or hemorrhagic stroke (lobar versus deep).
Separate prediction of intracerebral hemorrhage and ischemic stroke
Bart S. Ferket, Bob J.H. van Kempen, Renske G. Wieberdink, Ewout W. Steyerberg, Peter J. Koudstaal, Albert Hofman, Eyal Shahar, Rebecca F. Gottesman, Wayne Rosamond, Jorge R. Kizer, Richard A. Kronmal, Bruce M. Psaty, W.T. Longstreth, Jr, Thomas Mosley, Aaron R. Folsom, M.G. Myriam Hunink, and M. Arfan Ikram
Neurology 10.1212/WNL.0000000000000427; published ahead of print April 23, 2014