Level of Systolic Blood Pressure Within the Normal Range and Risk of Recurrent Stroke

Study Questions:

What is the association of systolic blood pressure (SBP) and risk for vascular events among patients with a recent ischemic stroke?

Methods:

This was a post-hoc analysis using data from the PROFESS (Prevention Regimen for Effectively Avoiding Second Strokes) trial; a multicenter trial involving 20,330 patients (ages ≥50 years) with recent non–cardioembolic ischemic stroke, recruited from September 2003 through July 2006. The trial used a 2 x 2 factorial design to compare a combination of aspirin and extended-release dipyridamole versus clopidogrel and telmisartan or placebo. All patients also received antihypertensive medications at the discretion of the investigators. Patients were excluded if they had a primary hemorrhagic stroke, severe disability after the qualifying stroke, contraindications to one of the study antiplatelet agents, or other factors making them unsuitable for randomization. Patients were categorized based on their mean SBP level: very low–normal (<120 mm Hg), low-normal (120-<130 mm Hg), high-normal (130-<140 mm Hg), high (140-<150 mm Hg), and very high (≥150 mm Hg). The primary outcome of interest was first recurrence of stroke of any type. The secondary outcome was a composite outcome of stroke, myocardial infarction, or death from vascular causes.

Results:

Among the 20,330 patients, the mean age was 66.1 years and 36% were female. The recurrent stroke rates were 8.0% (95% confidence interval [CI], 6.8%-9.2%) for the very low–normal SBP level group, 7.2% (95% CI, 6.4%-8.0%) for the low-normal SBP group, 6.8% (95% CI, 6.1%-7.4%) for the high-normal SBP group, 8.7% (95% CI, 7.9%-9.5%) for the high SBP group, and 14.1% (95% CI, 13.0%-15.2%) for the very high SBP group. Compared with patients in the high-normal SBP group, the risk of recurrence of stroke of any type was higher for patients in the very low–normal SBP group (adjusted hazard ratio [AHR], 1.29; 95% CI, 1.07-1.56). The risk was also elevated in the high SBP group (AHR, 1.23; 95% CI, 1.07-1.41), and in the very high SBP group (AHR, 2.08; 95% CI, 1.83-2.37). In terms of the secondary composite outcome, the risk was higher among patients in the very low–normal SBP group (AHR, 1.31; 95% CI, 1.13-1.52), in the low-normal SBP group (AHR, 1.16; 95% CI, 1.03-1.31), in the high SBP group (AHR, 1.24; 95% CI, 1.11-1.39), and in the very high SBP group (AHR, 1.94; 95% CI, 1.74-2.16).

Conclusions:

The investigators concluded that among patients with recent non–cardioembolic ischemic stroke, SBP levels during follow-up in the very low–normal (<120 mm Hg), high (140-<150 mm Hg), or very high (≥150 mm Hg) range were associated with increased risk of recurrent stroke.

Perspective:

These data suggest a lack of benefit to lowering SBP <130 mm Hg among patients with recent non–cardioembolic ischemic stroke. Randomized controlled trials to fully evaluate this hypothesis prior to changes in guideline recommendations are warranted.

Clinical Topics: Novel Agents, Statins

Keywords: Risk, Myocardial Infarction, Stroke, Follow-Up Studies, Platelet Aggregation Inhibitors, Reference Values, Ticlopidine, Blood Pressure, Benzoates, Recurrence, Benzimidazoles, Cardiology, Confidence Intervals, Dipyridamole


< Back to Listings