Lowering blood pressure to prevent stroke recurrence: a systematic review of long-term randomized trials

Albeit hypertension is a leading risk factor for an initial stroke, the role of blood pressure (BP) lowering to prevent a subsequent stroke is controversial. The present systematic review searched randomized trials published from January 1990 to January 2014 with the aim to assess antihypertensive treatment effects on recurrent stroke prevention. Seven randomized placebo-controlled trials enrolling 49,518 patients, two randomized trials not placebo controlled comparing antihypertensive drugs, and one randomized trial that compared the effects of intensive systolic BP lowering with a more conservative systolic BP management, were identified. The placebo-controlled trials had substantial methodological differences, explaining the difficulties to compare their results. An important obstacle arises from the large dispersion in the window's time between the qualifying stroke and randomization. Another barrier is the variation among studies in the recruited patient's stroke subtypes. Differences between trials could not be attributed to disparity in lowering BP or to different degrees of no adherence. The American Heart Association/American Stroke Association stated that although an absolute target of BP level has not been clearly defined, a reduction in recurrent stroke has been associated with an average lowering of 10/5 mm Hg. It should be taken into account that it is not advisable to reduce BP levels to <120/80 mm Hg. It should carry out an individualized selection, based on demographic characteristics and comorbidities (cardiovascular disease, diabetes mellitus, and chronic disease) among diuretics, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, or calcium channel blockers.