Women With First-Hand Tobacco Smoke Exposure Have a Higher Likelihood of Having an Unruptured Intracranial Aneurysm Than Nonsmokers: A Nested Case-Control Study

Background: The prevalence of unruptured intracranial aneurysms (UIA) in females who smoke cigarettes and the association between smoking and hypertension with purely incidental UIAs have been unexplored.

Objective: To obtain the prevalence of UIA among females and to assess the relationship between smoking and hypertension with a diagnosis of incidental UIAs.

Methods: A nested case-control study from a cohort of female patients aged between 30 and 60 yr with a brain magnetic resonance angiography (MRA) between 2016 and 2018. Incidental UIAs were compared to patients with normal MRAs. Smoking was characterized as never or former/current smokers. A logistic regression was used to evaluate the association between smoking, hypertension, or both, with a diagnosis of incidental UIAs.

Results: A total of 1977 patients had a brain MRA between 2016 and 2018. From 1572 nonsmoker patients, we encountered 30 with an UIA (prevalence: 1.9%). There were 405 patients with a positive smoking history, and 77 patients harbored an UIA (prevalence: 19%). Of 64 aneurysm patients and 130 random controls eligible for the case control, aneurysm patients were more likely to have a positive smoking history and hypertension compared with healthy controls (60% vs 18%, P ≤ .001; 44% vs 14%, P ≤ .001). A multivariable analysis demonstrated a significant association between a smoking history, hypertension, or both factors with an incidental UIA (odds ratio [OR] 5.8 CI 1.22-11.70; OR 3.8 CI 2.31-14.78; OR 12.6 CI 4.38-36.26; respectively).

Conclusion: Females who smoke cigarettes have a higher prevalence of UIAs than the general population. Smoking confers a higher risk for having a silent UIA, aggravated by hypertension. This population is an ideal target for potential screening.

Keywords: Cerebrovascular; Hypertension; Intracranial aneurysms; Screening; Smoking; Vascular malformation.