High initial blood pressure after acute stroke is associated with poor functional outcome

Abstract

Objective: To evaluate the relationship between high initial blood pressure and functional outcome in patients with acute stroke.

Design: An observational study based on the data from the Intravenous Nimodipine West European Stroke Trial (INWEST). INWEST was a placebo-controlled randomized study terminated prematurely; subsequent analysis found a correlation between diastolic BP (DBP) reduction caused by high-dose nimodipine and unfavourable outcome. Subjects. Of the 295 patients with acute ischaemic stroke (within 24 h) recruited in the INWEST, 265 were included in this analysis [n = 92 for placebo, n = 93 for low-dose nimodipine (1-mg h(-1)) and n=80 for high-dose nimodipine (2-mg h(-1))]. Definition. Initial BP was defined as BP at the time of randomization. Normal initial BP (NIBP)=systolic BP (SBP) 120-160 and DBP 60-90 mmHg (n=126). Four alternatives were defined as high initial BP (HIBP): (1) >160/90 (n=126), (2) >170/95 (n=106), (3) >180/100 (n=63), (4) >190/105 (n=45). Main outcome measures. Combined death or dependency (DD) (Barthel index < 60) at 21 days.

Results: In multiple logistic regression analyses, the odds ratio [OR] for DD at day 21 was significantly higher in patients with any definition of HIBP than with NIBP. For all patients, OR and 95% confidence intervals [CI] for 160/90 versus NIBP=3.1, 1.3-7.3, respectively; for 170/95=3.3, 1.4-8.1; for 180/100=7.0, 2.1-22.8; for 190/105=3.7, 1.1-12.4. For only placebo patients, OR and 95% CI for 160/90=4.8, 1.2-19.3; for 170/95=4.4, 1.1-17.8; for 180/100=12.7, 2.2-74.7; for 190/105=5.6, 1.1-30.0. The outcome was similar at 24 weeks but did not reach statistical significance for the placebo patients.

Conclusion: Patients with HIBP had a poor functional outcome after acute stroke.