LAUSR

OBJECTIVE Calcium channel blockers (CCBs) are antihypertensive agents with potential vascular protection effects. This study investigated whether CCB usage was associated with a lower incidence of unruptured intracranial aneurysm (UIA) instability (growth and rupture) in patients with hypertension. METHODS UIA patients were included in two prospective, multicenter cohort studies (IARP-CP and 100-Project cohorts). All patients received conservative treatment and were regularly followed up every 6 months by CT angiography for 2 years. Patients taking CCBs at least 5 days per week were considered CCB users; otherwise, they were considered non-CCB users. The primary endpoint was UIA instability (rupture, growth of > 20% and/or 1 mm in any dimension, or appearance of a new dome irregularity on imaging follow-up). RESULTS A total of 392 UIA patients with hypertension (191 male, 201 female; median age 57 years) were included with a mean follow-up duration of 21.7 ± 5.2 months. The primary endpoint was met in 81 patients (20.7%) during follow-up, including 68 patients with aneurysms that grew and 13 with aneurysms that ruptured. CCB users had a lower UIA instability rate than non-CCB users (27/237 [11.4%] vs 54/155 [34.8%], p < 0.001). Multivariable Cox analysis demonstrated that CCB use was associated with a lower risk of UIA instability (HR 0.37, 95% CI 0.22-0.61; p < 0.001). The protective effect of CCB use was consistent in patients taking a single antihypertensive agent (HR 0.22, 95% CI 0.12-0.40; p < 0.001) and patients taking > 1 antihypertensive agent (HR 0.42, 95% CI 0.20-0.87; p = 0.021). For patients with controlled hypertension, CCB use was still associated with a lower risk of UIA instability (HR 0.22, 95% CI 0.09-0.52; p = 0.001). CONCLUSIONS In UIA patients with hypertension, CCB use was associated with a lower incidence of aneurysm instability.