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Controversies in epidemiology of intracranial aneurysms and SAH

Abstract

Rupture of an intracranial aneurysm is the most common cause of subarachnoid haemorrhage (SAH), which is a life-threatening acute cerebrovascular event that typically affects working-age people. The exact prevalence of unruptured intracranial aneurysms (UIAs) is unknown, but at least one in 20 to 30 adults is likely to carry an asymptomatic UIA. Approximately one quarter of these UIAs rupture in a lifetime. Complex methodological challenges in conducting studies of epidemiology and risk factors for UIAs and SAH might have led to conclusions being drawn on the basis of epidemiological data of variable quality. We believe that, as a result, misconceptions about UIAs and SAH may have arisen. In this Perspectives article, we discuss three possible misconceptions about the epidemiology of UIAs and SAH, and suggest how the quality of future research could be improved.

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Acknowledgements

M.K. has received personal grants from the Sigrid Jusélius, Biomedicum Helsinki, Orion-Farmos Research, and Instrumentarium Research Foundations, as well as from the Finnish Medical Association. J.K. is supported by the Academy of Finland (grants 265240, 263278). The study sponsors did not have any role in the writing of the manuscript, or in the decision to submit the manuscript for publication.

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M.K. researched data for the article and wrote the article. J.K. reviewed/edited the manuscript before submission. Both authors provided substantial contribution to discussion of content.

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Correspondence to Miikka Korja.

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Korja, M., Kaprio, J. Controversies in epidemiology of intracranial aneurysms and SAH. Nat Rev Neurol 12, 50–55 (2016). https://doi.org/10.1038/nrneurol.2015.228

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