BACKGROUND AND PURPOSE: Statins may improve cerebral vasomotor reactivity 
through cholesterol-dependent and -independent mechanisms. A phase II randomized 
controlled trial was conducted to examine the hypothesis that acute pravastatin 
treatment could improve cerebrovascular autoregulation and reduce 
vasospasm-related complications after aneurysmal subarachnoid hemorrhage (SAH).
METHODS: A total of 80 aneurysmal SAH (aSAH) patients (18 to 84 years of age) 
within 72 hours from the ictus were randomized equally to receive either oral 
pravastatin (40 mg) or placebo daily for up to 14 days. Primary end points were 
the incidence, duration, and severity of cerebral vasospasm, and duration of 
impaired autoregulation estimated from transcranial Doppler ultrasonography. 
Secondary end points were the incidence of vasospasm-related delayed ischemic 
deficits (DIDs) and disability at discharge.
RESULTS: Prerandomization characteristics were balanced between the 2 groups. No 
treatment-related complication was observed. The incidences of vasospasm and 
severe vasospasm were reduced by 32% (P=0.006) and 42% (P=0.044), respectively, 
and the duration of severe vasospasm was shortened by 0.8 days (P=0.068) in the 
pravastatin group. These measurements were maximal on the ipsilateral side of 
ruptured aneurysms. The duration of impaired autoregulation was shortened 
bilaterally (P< or =0.01), and the incidence of vasospasm-related DIDs and 
mortality were decreased by 83% (P<0.001) and 75% (P=0.037), respectively, in 
the pravastatin group.
CONCLUSIONS: Acute treatment with pravastatin after aSAH is safe and ameliorates 
cerebral vasospasm, improves cerebral autoregulation, and reduces 
vasospasm-related DID. Unfavorable outcome at discharge was reduced primarily 
because of a reduction in overall mortality. This is the first demonstration of 
clinical benefits with immediate statin therapy for an acute cerebrovascular 
disorder.