Hypertension and its treatment in the NINDS rt-PA Stroke Trial

Abstract

Background and purpose: We examined the frequency, course, and treatment of hypertension in the NINDS rt-PA Stroke Trial.

Methods: Blood pressure (BP) was measured at the time of admission, at randomization, and then 36 times during the first 24 hours after randomization. Patients with a systolic BP of >185 mm Hg and a diastolic BP of >110 mm Hg at admission were defined as hypertensive before randomization, and those with a systolic BP of >180 mm Hg or a diastolic BP of >105 mm Hg within the first 24 hours after randomization were defined as hypertensive after randomization. Standardized clinical assessments were conducted at 24 hours and at 3 months. Post hoc analyses were conducted to evaluate the association of antihypertensive therapy with clinical outcomes.

Results: Of the 624 patients, 121(19%) had hypertension on admission and 372 (60%) had hypertension in the 24 hours after randomization. The use of antihypertensive therapy before randomization (tPA 9%, placebo 9%) and after randomization (tPA 24%, placebo 29%) was similar between placebo- and tPA-treated patients. No adverse effects of prerandomization antihypertensive therapy on 3-month favorable outcome were detected for either the placebo- or tPA-treated groups. For placebo patients with hypertension in the 24 hours after randomization, clinical outcome measures were similar for those patients who did and did not receive antihypertensive therapy after randomization (P > or = 0.26); antihypertensive therapy was not associated with declines in BP (P = 0.44) or with abrupt declines (P = 0.14). Those tPA patients who were hypertensive after randomization and received antihypertensive therapy were less likely to have a favorable outcome at 3 months (P < 0.01) than those who were hypertensive and did not receive antihypertensive therapy.

Conclusions: The frequency of hypertension and the use of antihypertensive therapy were similar between the tPA and placebo groups in the NINDS rt-PA Stroke Trial. In the placebo group, antihypertensive therapy was not associated with less favorable outcomes at 3 months; postrandomization antihypertensive therapy was associated with less favorable outcomes for the tPA patients who were hypertensive. However, because of the nonrandomized use of antihypertensive therapy and the many post hoc comparisons leading to type 1 errors, the significance of this observation is unclear. Careful attention to BP and gentle management remain warranted for stroke patients treated with tPA.