Short-term blood pressure variability in acute stroke: post hoc analysis of the
controlling hypertension and hypotension immediately post stroke and continue or
stop post-stroke antihypertensives collaborative study trials.
Author(s): Manning LS(1), Mistri AK(2), Potter J(2), Rothwell PM(2), Robinson TG(2).
Affiliation(s): Author information:
(1)From the Department of Cardiovascular Sciences and NIHR Biomedical Research
Unit in Cardiovascular Disease, University of Leicester, Leicester, United
Kingdom (L.S.M., A.K.M., T.G.R.); Faculty of Medicine and Health Sciences,
Norwich Medical School, University of East Anglia, Norwich, United Kingdom
(J.P.); and Nuffield Department of Clinical Neurosciences, John Radcliffe
Hospital, Oxford, United Kingdom (P.M.R.). lm313@le.ac.uk. (2)From the Department
of Cardiovascular Sciences and NIHR Biomedical Research Unit in Cardiovascular
Disease, University of Leicester, Leicester, United Kingdom (L.S.M., A.K.M.,
T.G.R.); Faculty of Medicine and Health Sciences, Norwich Medical School,
University of East Anglia, Norwich, United Kingdom (J.P.); and Nuffield
Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, United
Kingdom (P.M.R.).
Publication date & source: 2015, Stroke. , 46(6):1518-24
BACKGROUND AND PURPOSE: Short-term blood pressure variability (BPV) may predict
outcome in acute stroke. We undertook a post hoc analysis of data from 2
randomized controlled trials to determine the effect of short-term BPV on 2-week
outcome.
METHODS: Controlling Hypertension and Hypotension Immediately Post Stroke
(CHHIPS) was a trial of BP-lowering, enrolling 179 acute stroke patients
(onset<36 hours). Continue or Stop Post-Stroke Antihypertensives Collaborative
Study (COSSACS) compared a strategy of continuation versus temporarily stopping
prestroke antihypertensive therapy in 763 acute stroke patients (onset<48 hours).
BPV at baseline (defined as SD, coefficient of variation, variation independent
of the mean, and average real variability) was derived from standardized casual
cuff BP measures (6 readings<30 minutes). Adjusted logistic regression models
were used to assess the relation between BPV and death and disability (modified
Rankin scale>3) at 2 weeks.
RESULTS: Seven hundred six (92.5%) and 171 (95.5%) participants were included in
the analysis for the COSSACS and CHHIPS data sets, respectively. Adjusted
logistic regression analyses revealed no statistically significant associations
between any of the included BPV parameters with 2-week death or disability in
either study data set: COSSACS, odds ratio SD systolic BP 0.98 (0.78-1.23);
CHHIPS, odds ratio SD systolic BP 0.97 (0.90-1.11).
CONCLUSIONS: When derived from casual cuff BP measures, short-term BPV is not a
useful predictor of early (2 weeks) outcome after acute stroke. Differing
methodology may account for the discordance with previous studies indicating
long-term (casual BPV) and short-term (beat-to-beat BPV) prognostic value.
CLINICAL TRIAL REGISTRATION: COSSACS was registered on the International Standard
Randomised Controlled Trial Register; URL: http://www.isrctn.com. Unique
identifier: ISRCTN89712435. CHHIPS was registered on the National Research
Register; URL: http://public.ukcrn.org.uk. Unique identifier: N0484128008.
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