Can A, et al. – The researchers planned this case-control study to examine the relationship between intracranial aneurysm (IA) rupture and smoking intensity and duration, as well as the duration of smoking cessation. At presentation, current cigarette smoking, smoking intensity, and smoking duration were significantly correlated with ruptured IAs. The significantly increased risk, however, persisted after smoking cessation, and smoking cessation did not confer a reduced risk of aneurysmal subarachnoid hemorrhage beyond that of reducing the cumulative dose.

• Between 1990 and 2016, the researchers examined 4,701 patients with 6,411 IAs diagnosed at the Brigham and Women's Hospital and Massachusetts General Hospital.
• Individuals were divided into patients with ruptured aneurysms and controls with unruptured aneurysms.
• Univariable and multivariable logistic regression analyses were performed to determine the association between smoking status and ruptured IAs at presentation.
• They evaluated the association between ruptured aneurysms and number of packs per day, duration of smoking, and duration since smoking cessation in a subgroup analysis among former and current smokers.

• Current (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.89–2.59) and former smoking status (OR 1.56, 95% CI 1.31-1.86) were correlated with rupture status at presentation compared with never smokers in multivariable analysis.
• Years smoked (OR 1.02, 95% CI 1.01-1.03) and packs per day (OR 1.46, 95% CI 1.25-1.70) were significantly correlated with ruptured aneurysms at presentation, while duration since cessation among former smokers was not significant (OR 1.00, 95% CI 0.99-1.02) in a subgroup analysis among current and former smokers.