Background: Studies have shown that interventions which reduce total and low-density lipoprotein cholesterol levels also reduce coronary heart disease (CHD) and stroke events in those with a history of CHD. However, it is uncertain whether treatment to alter cholesterol levels can prevent recurrence of either stroke or subsequent cardiovascular events and whether differences in outcomes exist between classes of lipid-lowering therapy. This is an update of a Cochrane review first published in 2002.
Objectives: To investigate the effect of altering serum lipids pharmacologically for preventing subsequent cardiovascular disease and stroke recurrence in patients with a history of stroke.
Search strategy: We searched the Cochrane Stroke Group Trials Register (last searched December 2008), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2008), MEDLINE (1966 to December 2008) and EMBASE (1980 to December 2008). We contacted pharmaceutical companies known to produce a lipid-lowering agent for information on relevant publications or unpublished work.
Selection criteria: Unconfounded randomised trials of participants aged 18 years and over with a history of stroke or transient ischaemic attack (TIA).
Data collection and analysis: Two review authors independently selected trials, assessed quality and extracted data.
Main results: We included eight studies involving approximately 10,000 participants. The active interventions were pravastatin, atorvastatin, simvastatin, clofibrate, and conjugated oestrogen. Fixed-effect analysis showed no overall effect on stroke recurrence but statin therapy alone had a marginal benefit in reducing subsequent cerebrovascular events in those with a previous history of stroke or TIA (odds ratio (OR) 0.88, 95% confidence interval (CI) 0.77 to 1.00). There was no evidence that such intervention reduced all-cause mortality or sudden death (OR 1.00, 95% CI 0.83 to 1.20). Three statin trials showed a reduction in subsequent serious vascular events (OR 0.74, 95% CI 0.67 to 0.82).
Authors' conclusions: There is evidence that statin therapy in patients with a history of ischaemic stroke or TIA significantly reduces subsequent major coronary events but only marginally reduces the risk of stroke recurrence. There is no clear evidence of beneficial effect from statins in those with previous haemorrhagic stroke and it is unclear whether statins should be started immediately post stroke or later. In view of this and the evidence of the benefit of statin therapy in those with a history of CHD, patients with ischaemic stroke or TIA, with or without a history of established CHD, should receive statins.