This study was published in Stroke 2013 Mar 21
Study title and authors:
Risk of Rupture of an Intracranial Aneurysm Based on Patient Characteristics: A Case-Control Study.
Vlak MH, Rinkel GJ, Greebe P, Algra A.
From the Utrecht Stroke Center, Department of Neurology and Neurosurgery, Rudolf Magnus Institute of Neuroscience and Julius Center for Health Sciences and Primary Care, University Medical Center, Utrecht, The Netherlands; and Department of Neurology, Slotervaart Hospital, Amsterdam, The Netherlands.
This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/23520239
This study investigated lifestyle and personal characteristics as risk factors for the rupture of brain aneurysms. (An aneurysm is a bulge in a blood vessel that's caused by a weakness in the blood vessel wall). The study included 250 patients with a rupured brain aneurysm and 206 patients with an unruptured brain aneurysm.
Regarding cholesterol levels, the study found that those with high cholesterol levels had a 60% decreased risk of of a ruptured brain aneurysm.