Background and purpose: Compared with normotensive individuals, there is a higher incidence of stroke in patients with hypertensive, as well as prehypertensive, blood pressure levels (ie, 120-139/80-89 mm Hg). Although several studies have shown that blood pressure reduction in hypertensive patients reduces the incidence of cardiovascular events, including stroke, it is still unknown whether treatment of prehypertensive blood pressure levels has a similar effect. We sought to determine whether reduction in blood pressure in the prehypertensive range reduces the incidence of stroke by performing a meta-analysis of randomized trials comparing an antihypertensive drug against placebo in cohorts with prehypertensive baseline blood pressure levels.
Methods: Randomized controlled trials performed with the 95 different antihypertensive agents available in the market were identified using MEDLINE, returning a total of 2852 results. Exclusion criteria included: average blood pressure of ≥ 140/90 mm Hg at baseline, crossover studies, and lack of a control group receiving placebo.
Results: A total of 16 trials involving 70 664 patients were included. Patients randomized to the active treatment arm had a statistically significant 22% reduction in the risk of stroke compared with placebo, with little heterogeneity among the trials (I(2), 18.0%; RR, 0.78 [95% CI, 0.71-0.86]; P<0.000001). To prevent 1 stroke, 169 patients had to be treated with a blood-pressure-lowering medication for an average of 4.3 years.
Conclusions: The risk of stroke is significantly reduced with antihypertensive therapy in cohorts with prehypertensive blood pressure levels. These findings can have important clinical implications.