Lowblood pressure and adverse outcomes in acute stroke:HeadPoSTstudy explanations

Menglu Ouyang, Paula Munoz-Venturelli, Laurent Billot, Xia Wang, Lili Song, Hisatomi Arima, Pablo M. Lavados, Maree L. Hackett, Veronica V. Olavarria, Alejandro Brunser, Sandy Middleton, Octavio M. Pontes-Neto, Tsong Hai Lee, Caroline L. Watkins, Thompson Robinson, Craig S. Anderson*

*Corresponding author for this work

Research output: Contribution to journalJournal Article peer-review

10 Scopus citations

Abstract

Objective: As uncertainties exist over underlying causes, we aimed to define the characteristics and prognostic significance of low blood pressure (BP) early after the onset of acute stroke. Methods: Post hoc analyzes of the international Head Positioning in acute Stroke Trial (HeadPoST), a pragmatic cluster-crossover randomized trial of lying flat versus sitting up in stroke patients from nine countries during 2015- 2016. Associations of baseline BP and death or dependency [modified Rankin scale (mRS) scores 3-6] and serious adverse events (SAEs) at 90 days were assessed in generalized linear mixed models with adjustment for multiple confounders. SBP and DBP was analysed as continuous measures fitted with a cubic spline, and as categorical measures with low (<10th percentile) and high (-140 and -90 mmHg, respectively) levels compared with a normal range (-10th percentile; 120-139 and 70- 89 mmHg, respectively). Results: Among 11 083 patients (mean age 68 years, 39.9% women) with baseline BP values, 7.2 and 11.7% had low SBP (<120 mmHg) and DBP (<70 mmHg), respectively. Patients with low SBP were more likely to have preexisting cardiac and ischemic stroke and functional impairment, and to present earlier with more severe neurological impairment than other patients. Nonlinear 'Jshaped' relationships of BP and poor outcome were apparent: Compared with normal SBP, those with low SBP had worse functional outcome (adjusted odds ratio 1.27, 95% confidence interval 1.02-1.58) and more SAEs, particularly cardiac events, with adjustment for potential confounders to minimize reverse causation. The findings were consistent for DBP and were stronger for ischemic rather than hemorrhagic stroke. Conclusion: The prognostic significance of low BP on poor outcomes in acute stroke was not explained by reverse causality from preexisting cardiovascular disease, and propensity towards greater neurological deficits and cardiac events. These findings provide support for the hypothesis that low BP exacerbates cardiac and cerebral ischemia in acute ischemic stroke.

Original languageEnglish
Pages (from-to)273-279
Number of pages7
JournalJournal of Hypertension
Volume39
Issue number2
DOIs
StatePublished - 02 2021

Bibliographical note

Publisher Copyright:
© 2021 Lippincott Williams and Wilkins. All rights reserved.

Keywords

  • Acute stroke
  • Blood pressure
  • Hypotension
  • Outcome
  • Trial

Fingerprint

Dive into the research topics of 'Lowblood pressure and adverse outcomes in acute stroke:HeadPoSTstudy explanations'. Together they form a unique fingerprint.

Cite this