Effect of statin on progression of symptomatic intracranial atherosclerosis

Symptomatic intracranial atherosclerosis (ICAS) is a dynamic disease that frequently progresses. Statins have been shown to have anti-atherosclerotic activity. We therefore investigated whether statins could prevent progression of ICAS.

This retrospective cohort study assessed 55 patients with acute ischemic stroke and symptomatic ICAS in the middle cerebral or basilar arteries as shown on magnetic resonance angiography (MRA), with follow-up MRA performed more than 1 year after the index stroke. Change in ICAS was classified as progressive, regressive, or stable. Baseline clinical characteristics and risk factor control during follow-up were assessed, and laboratory tests were performed at the time of follow-up MRA. The statin group was defined as patients regularly treated with statins for more than 75% of the follow-up period; the remaining patients were defined as the non-statin group.

At a median follow-up time of 21.8 months (range, 11.8-66.1 months), the statin group consisted of 26 (47.3%) patients and the non-statin group of 29 (52.7%). During follow-up, 6 (10.9%) patients progressed, 14 (25.5%) regressed, and 35 (63.6%) remained stable. Statin treatment was significantly associated with non-progression of ICAS (p=0.024). Two patients in the non-statin group had recurrent strokes. Border-zone infarcts were associated with progression of ICAS (3/6, 50%; p=0.007), whereas risk factors and inflammatory biomarkers were not related to progression.

Treatment with statins may prevent progression of symptomatic ICAS. Prospective randomized controlled trials are required to confirm that statins protect against such progression.