[Secondary prevention of recurrent stroke by lowering cholesterol levels and blood pressure]

Abstract

The most important risk factor for stroke is blood pressure: lowering the diastolic pressure by 5-6 mmHg or the systolic pressure by 10 mmHg will reduce the number of strokes in the general population (primary prevention) by 30-40% over 4-5 years. This effect is enhanced by the concurrent use of diuretics. The association between stroke and serum cholesterol was unclear until trials on preventing cardiovascular disease showed the introduction of statins to be clearly beneficial on strokes. In the recent 'Stroke prevention by aggressive reduction in cholesterol levels' (SPARCL) trial, high-dose statin therapy was shown to reduce the risk of fatal and non-fatal stroke in patients with a history of ischaemic stroke or transient ischaemic attack (TIA), but without manifest coronary disease (secondary prevention). A difference in LDL-cholesterol of 1.4 mmol/l was associated with a significant absolute 5-year risk reduction of fatal and non-fatal stroke of 2.2%, whereas the risk of major cardiovascular events was reduced by 3.5%. It is already known that stroke or TIA should be regarded as a 'coronary heart disease risk equivalent' for which secondary prevention guidelines apply. However, high-dose statin therapy should be given only after careful selection of the stroke patient at very high risk because of its high cost, adverse effects and a possible increase in haemorrhagic stroke.