High Blood Pressure and the Risk of Stroke

High blood pressure is the most prevalent modifiable risk factor for stroke. Observational and interventional studies have shown that lowering blood pressure with drugs, even in normotensive high-risk patients, may achieve effective primary stroke prevention. Uncertainties remain concerning the optimal blood pressure target, especially in older people with low diastolic blood pressures. Data from The Perindopril Protection Against Recurrent Stroke Study and other placebo-controlled trials showed that secondary prevention of stroke can also be provided by blood pressure lowering medication, even in normotensive subjects. Possible differences in the preventive potential of the various available antihypertensive agents remain to be documented, both for the primary and secondary prevention of stroke. Much uncertainty remains concerning the optimal blood pressure management in the context of acute stroke. Some trials currently evaluate the effect of lowering blood pressure on subsequent outcome, such as mortality and dependence, whereas others assess the effect of increasing blood pressure. Conflicting results have been obtained from small trials. These are possibly explained by differences in inclusion criteria or follow-up duration, or by a U-shaped relationship between systolic blood pressure at admission and outcome. This review focuses on the preventive trials that led to implement the current guidelines concerning blood pressure management in relation to the risk of stroke. It briefly describes ongoing trials that test new strategies to improve the management of acute stroke.