[Statins and stroke]

The occurrence of stroke increases with age, particularly affecting the older elderly, a population also at higher risk for coronary heart disease (CHD). Epidemiological and observational studies have not shown a clear association between cholesterol levels and all causes of stroke. Nevertheless, large, long-term statin trials in patients with established CHD or et high risk for CHD (diabetes, hypertension) have shown that statins decrease stroke incidence in these populations even with a normal baseline cholesterol concentration. In patients with previous stroke statins reduce the incidence of coronary events, but whether they actually reduce the incidence of recurrent strokes in secondary prevention is unproved. In this review we discuss the potential reason for the effects of statins on stroke and the mechanisms of action. Statins probably reduce stroke by a variety of mechanisms. Several studies indicate that statins have multiple effects beyond lowering the cholesterol level. There is evidence that statins have neuroprotective properties for the acute ischaemic brain. Statins interfere with platelet aggregation and have anti-inflammatory and antioxidative properties. Also statins promote stabilisation of atherosclerotic plaques and improve blood flow to the ischaemic brain. The protective effects of statins might be due to their direct effect on endothelial cells leading to improved nitric oxide (NO) bioavailability. However further studies are needed to understand the full role of statins in the prevention of stroke in patients without established cardiovascular disease, representative of the typical stroke population.