Independent Risk Factors for Intracranial Aneurysms and Their Joint Effect A Case-Control Study

<p>Background and Purpose-Three percent of the population has an unruptured intracranial aneurysm (UIA). We aimed to identify independent risk factors from lifestyle and medical history for the presence of UIAs and to investigate the combined effect of well-established risk factors.</p><p>Methods-We studied 206 patients with an UIA who never had a subarachnoid hemorrhage and 574 controls who were randomly retrieved from general practitioner files. All participants filled in a questionnaire on potential risk factors for UIAs. With logistic regression analysis, we identified independent risk factors for UIA and assessed their combined effect.</p><p>Results-Independent risk factors were current smoking (odds ratio[ OR], 3.0; 95% confidence interval[ CI], 2.0-4.5), hypertension (OR, 2.9; 95% CI, 1.9-4.6), family history of stroke other than subarachnoid hemorrhage (OR, 1.6; 95% CI, 1.0-2.5), hypercholesterolemia (OR, 0.5; 95% CI, 0.3-0.9), and regular physical exercise (OR, 0.6; 95% CI, 0.3-0.9). The joint risk of smoking and hypertension was higher (OR, 8.3; 95% CI, 4.5-15.2) than the sum of the risks independently.</p><p>Conclusions-Current smoking, hypertension, and family history of stroke increase the risk of UIA, with smoking and hypertension having an additive effect, whereas hypercholesterolemia and regular physical exercise decrease this risk. A healthy lifestyle probably reduces the risk of UIA and thereby possibly also that of aneurysmal subarachnoid hemorrhage. Whether smoking and hypertension increase the risk of aneurysmal subarachnoid hemorrhage only through an increased risk of aneurysm formation or also through an increased risk of rupture remains to be established. (Stroke. 2013;44:984-987.)</p>

Growth of Asymptomatic Intracranial Fusiform Aneurysms

PurposeGrowth of intracranial fusiform aneurysms (IFA) may become clinically problematic through a mass effect or rupture. We investigated the growth rate and factors contributing to growth in asymptomatic untreated IFA.MethodAs a retrospective review, we assessed patients diagnosed with asymptomatic IFA between August 2000 and September 2014, all untreated. No acute or symptomatic dissecting lesions were considered. Clinical and serial angiographic follow-up data were analyzed, defining growth as expansion&gt;2mm in one or more dimensions. A binary logistic regression model and Kaplan-Meier method were applied for statistical analysis.ResultsThe mean follow-up in the 82 eligible patients was 47.7 months (range 12-190 months). Among them, 7 aneurysms (8.5%, 2.1% per aneurysm year) demonstrated growth (in any dimension). In univariate analysis, height and multiplicity of aneurysms emerged as significant factors in terms of growth. Height remained an independent risk factor in the binary logistic regression model, with receiver operating curves indicating a threshold of 6.9mm initial height in determining IFA growth (area under the curve 0.804). Of the patients six (except one who underwent endovascular treatment) were observed during continued follow-up monitoring. All six lesions were stable in serial imaging tests, without further detectable growth or rupture (mean 33 months).ConclusionMost (91.5%) of the asymptomatic and untreated IFAs studied proved to be stable, with no continued growth; however, because aneurysm height proved to be independently predictive of growth (lesions&gt;6.9mm being at risk), periodic imaging is required in those left untreated. Growing but still asymptomatic aneurysms call for the utmost caution and care in decision-making.N