BACKGROUND: the pathophysiology of delayed neurological deficits (DNDs) 
following aneurysmal subarachnoid hemorrhage (SAH) is complex, and is not 
limited to arterial narrowing (vasospasm) and classical ischemia. Thus, combined 
drug approaches, or therapies with multiple effects, may have the greatest 
potential for benefit. Statins are known to have pleiotropic vascular effects, 
some of which may interrupt the pathogenesis of DNDs. Based on promising 
preliminary reports, many clinicians routinely administer statins to prevent 
DNDs.
METHODS: a systematic review was performed to identify and summarize all animal 
research, observational studies, randomized controlled trials (RCTs) and 
meta-analyses which have evaluated the use of statins in the management of SAH.
RESULTS: nine animal studies, nine observational (cohort and case-control) 
studies, six RCTs and three meta-analyses were identified. Animal studies have 
generally administered statin doses that, when adjusted for body weight, are 
10-80 times larger than what is used in humans. Nevertheless, these models have 
consistently reported statins to reduce vasospasm and to demonstrate additional 
neuroprotective effects. However, observational studies have not revealed an 
association between statin-use and reduced DNDs or improved neurological 
outcomes. Results of RCTs have been inconsistent and limited by small sample 
size, but together suggest that statins may reduce DNDs, with no clear impact on 
mortality or neurological recovery. Optimal drug administration strategies 
(timing of initiation, most effective dose and duration) have not been 
clarified.
CONCLUSIONS: the role of statins in the management of patients with SAH remains 
unclear. Although promising, statins should not, at this time, be considered 
standard care.