Blood pressure in acute stroke
Authors: Else Charlotte Sandset
Journal: The Lancet Neurology (2014)

Although great advances have been made in stroke medicine in the past two decades, some questions about treatment in the acute phase of stroke remain. One such question is how to manage blood pressure? Blood pressure is often increased in acute ischaemic and haemorrhagic stroke,1Leonardi-Bee J Bath PM Phillips SJ Sandercock PA Blood pressure and clinical outcomes in the International Stroke Trial.Stroke. 2002; 33: 1315-1320Crossref PubMed Scopus (770) Google Scholar and findings from epidemiological studies suggest that high blood pressure in the acute phase is associated with poor outcome.1Leonardi-Bee J Bath PM Phillips SJ Sandercock PA Blood pressure and clinical outcomes in the International Stroke Trial.Stroke. 2002; 33: 1315-1320Crossref PubMed Scopus (770) Google Scholar The results of three large randomised clinical trials on blood pressure lowering in acute stroke—the Chinese Antihypertensive Trial in Acute Ischaemic Stroke2He J Zhang Y Xu T et al.Effects of immediate blood pressure reduction on death and major disability in patients with acute ischemic stroke: the CATIS randomized clinical trial.JAMA. 2014; 311: 479-489Crossref PubMed Scopus (286) Google Scholar, the Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage Trial (INTERACT-2),3Anderson CS Heeley E Huang Y et al.Rapid blood-pressure lowering in patients with acute intracerebral hemorrhage.N Engl J Med. 2013; 368: 2355-2365Crossref PubMed Scopus (992) Google Scholar and the Scandinavian Candesartan Acute Stroke Trial4Sandset EC Bath PM Boysen G et al.The angiotensin-receptor blocker candesartan for treatment of acute stroke (SCAST): a randomised, placebo-controlled, double-blind trial.Lancet. 2011; 377: 741-750Summary Full Text Full Text PDF PubMed Scopus (402) Google Scholar—suggest that treatment should differ according to the type of stroke. In The Lancet Neurology, findings from two Articles provide new evidence for the importance of blood pressure in acute stroke. In one study, using data from the population-based Oxford Vascular Study, Urs Fischer and colleagues compared prestroke blood pressure values with blood pressure measured in the acute phase, and assessed whether this differs in ischaemic versus haemorrhagic stroke.5Fischer U Cooney MT Bull LM et al.Acute post-stroke blood pressure relative to pre-morbid levels in intracerebral haemorrhage versus major ischaemic stroke: population-based study.Lancet Neurol. 2014; (published online Feb 28.)http://dx.doi.org/10.1016/S1474-4422(14)70031-6PubMed Google Scholar Patients with intracerebral haemorrhage had a steeper rise in blood pressure, higher blood pressure in the acute phase, and a more substantial fall within the first 24 h than did patients with ischaemic stroke.5Fischer U Cooney MT Bull LM et al.Acute post-stroke blood pressure relative to pre-morbid levels in intracerebral haemorrhage versus major ischaemic stroke: population-based study.Lancet Neurol. 2014; (published online Feb 28.)http://dx.doi.org/10.1016/S1474-4422(14)70031-6PubMed Google Scholar In the other study, Lisa Manning and colleagues did a post-hoc analysis of the INTERACT-2 trial—a randomised trial of intensive versus guideline blood pressure lowering in acute intracerebral haemorrhage—assessing the prognostic significance of blood pressure variability in the hyperacute phase (first 24 h) and the acute phase (days 2–7) after intracerebral haemorrhage.3Anderson CS Heeley E Huang Y et al.Rapid blood-pressure lowering in patients with acute intracerebral hemorrhage.N Engl J Med. 2013; 368: 2355-2365Crossref PubMed Scopus (992) Google Scholar, 6Manning L Hirakawa Y Arima H et al.Blood pressure variability and outcome in acute intracerebral haemorrhage: post-hoc analysis of the INTERACT2 randomised controlled trial.Lancet Neurol. 2014; (published online Feb 13.)http://dx.doi.org/0.1016/S1474-4422(14)70018-3PubMed Google Scholar Episodic hypertension, single high systolic blood pressure, and variability of blood pressure in the hyperacute and the acute phases of an intracerebral haemorrhage were predictors of poor functional outcome.6Manning L Hirakawa Y Arima H et al.Blood pressure variability and outcome in acute intracerebral haemorrhage: post-hoc analysis of the INTERACT2 randomised controlled trial.Lancet Neurol. 2014; (published online Feb 13.)http://dx.doi.org/0.1016/S1474-4422(14)70018-3PubMed Google Scholar The findings from these two studies suggest that patients with ischaemic stroke caused by small-vessel disease, and patients with deep or posterior haemorrhages, have higher blood pressure after stroke than patients with other ischemic stroke aetiologies or lobar haemorrhages, and when compared with recent pre-morbid measurements also have a steeper increase in blood pressure.5Fischer U Cooney MT Bull LM et al.Acute post-stroke blood pressure relative to pre-morbid levels in intracerebral haemorrhage versus major ischaemic stroke: population-based study.Lancet Neurol. 2014; (published online Feb 28.)http://dx.doi.org/10.1016/S1474-4422(14)70031-6PubMed Google Scholar These are important findings, indicating that the effects of blood pressure should be differentiated and managed, according to not only the type of stroke, but also to aetiology or lesion location. Such differentiation should be a key area for future research. For clinicians, the data presented in the papers suggest that we should closely monitor blood pressure in acute stroke. In patients with intracerebral haemorrhage, we should strive to maintain blood pressure at a constant level. However, the investigators showed an association between increasing blood pressure variability and greater intensity of blood pressure-lowering treatment.6Manning L Hirakawa Y Arima H et al.Blood pressure variability and outcome in acute intracerebral haemorrhage: post-hoc analysis of the INTERACT2 randomised controlled trial.Lancet Neurol. 2014; (published online Feb 13.)http://dx.doi.org/0.1016/S1474-4422(14)70018-3PubMed Google Scholar An intriguing question therefore remains: if high variability in blood pressure worsens outcome, and greater intensity of treatment increases variability, should blood pressure really be lowered? If so, how much should it be lowered and what is the best method to achieve the target level? In ischaemic stroke, blood pressure variability has been previously associated with poor outcome,7Rothwell PM Howard SC Dolan E et al.Prognostic significance of visit-to-visit variability, maximum systolic blood pressure, and episodic hypertension.Lancet. 2010; 375: 895-905Summary Full Text Full Text PDF PubMed Scopus (1240) Google Scholar, 8Geeganage C Tracy M England T et al.Relationship between baseline blood pressure parameters (including mean pressure, pulse pressure, and variability) and early outcome after stroke: data from the Tinzaparin in Acute Ischaemic Stroke Trial (TAIST).Stroke. 2011; 42: 491-493Crossref PubMed Scopus (81) Google Scholar, 9Endo K Kario K Koga M et al.Impact of early blood pressure variability on stroke outcomes after thrombolysis: the SAMURAI rt-PA Registry.Stroke. 2013; 44: 816-818Crossref PubMed Scopus (76) Google Scholar and an association between high blood pressure and poor outcome has been shown in several populations.1Leonardi-Bee J Bath PM Phillips SJ Sandercock PA Blood pressure and clinical outcomes in the International Stroke Trial.Stroke. 2002; 33: 1315-1320Crossref PubMed Scopus (770) Google Scholar, 8Geeganage C Tracy M England T et al.Relationship between baseline blood pressure parameters (including mean pressure, pulse pressure, and variability) and early outcome after stroke: data from the Tinzaparin in Acute Ischaemic Stroke Trial (TAIST).Stroke. 2011; 42: 491-493Crossref PubMed Scopus (81) Google Scholar However, there is no compelling evidence that lowering blood pressure is beneficial.2He J Zhang Y Xu T et al.Effects of immediate blood pressure reduction on death and major disability in patients with acute ischemic stroke: the CATIS randomized clinical trial.JAMA. 2014; 311: 479-489Crossref PubMed Scopus (286) Google Scholar, 4Sandset EC Bath PM Boysen G et al.The angiotensin-receptor blocker candesartan for treatment of acute stroke (SCAST): a randomised, placebo-controlled, double-blind trial.Lancet. 2011; 377: 741-750Summary Full Text Full Text PDF PubMed Scopus (402) Google Scholar Therefore, the prognostic significance of blood pressure variability in acute ischaemic stroke is an important topic for further investigation. The Articles in The Lancet Neurology add to the evidence suggesting that blood pressure management in haemorrhagic stroke is important, hence treatment should differ according to type of stroke, and sudden changes and variability in blood pressure should be avoided. Findings from two large stroke trials with an expected blood pressure-lowering effect are anticipated in 2014.10The ENOS Trial InvestigatorsGlyceryl trinitrate vs control, and continuing vs stopping temporarily prior antihypertensive therapy, in acute stroke: rationale and design of the Efficacy of Nitric Oxide in Stroke (ENOS) trial (ISRCTN99414122).Int J Stroke. 2006; 1: 245-249Crossref PubMed Scopus (103) Google Scholar, 11Saver JL Starkman S Eckstein M et al.Methodology of the Field Administration of Stroke Therapy - Magnesium (FAST-MAG) phase 3 trial: Part 1—rationale and general methods.Int J Stroke. 2014; 9: 215-219Crossref PubMed Scopus (38) Google Scholar Both trials have included patients with either ischaemic or haemorrhagic stroke and will add important evidence regarding blood pressure management in the acute phase. I declare that I have no conflicts of interest. Blood pressure variability and outcome after acute intracerebral haemorrhage: a post-hoc analysis of INTERACT2, a randomised controlled trialSystolic blood pressure variability seems to predict a poor outcome in patients with acute intracerebral haemorrhage. The benefits of early treatment to reduce systolic blood pressure to 140 mm Hg might be enhanced by smooth and sustained control, and particularly by avoiding peaks in systolic blood pressure. Full-Text PDF Acute post-stroke blood pressure relative to premorbid levels in intracerebral haemorrhage versus major ischaemic stroke: a population-based studyOur findings suggest that systolic blood pressure is substantially raised compared with usual premorbid levels after intracerebral haemorrhage, whereas acute-phase systolic blood pressure after major ischaemic stroke is much closer to the accustomed long-term premorbid level, providing a potential explanation for why the risks and benefits of lowering blood pressure acutely after stroke might be expected to differ. Full-Text PDF Open Access