Association of calcium channel blockers with lower incidence of intracranial aneurysm rupture and growth in hypertensive patients

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.