A new study provides additional support that inflammatory markers are
associated with a poor outcome following stroke, according to a research
article
by William Whiteley (Western General Hospital, Edinburgh) and colleagues.
The findings, published in the open-access journal PLoS Medicine this week
also show that inflammatory markers were not a useful addition to existing
prognostic models in predicting the outcome of stroke.
Every year, around the world,15 million people suffer a stroke when the
blood supply to the brain is interrupted; either by a blockage or a bleed
in
the blood vessels. Many people are left with permanent disabilities
because of the brain damage caused by stroke. Some previous studies have
suggested
that the levels of inflammatory markers in the blood could be useful in
predicting outcome after stroke.
In this prospective cohort study, Whiteley and colleagues followed the
progress of 844 patients who had experienced a recent stroke at the
Western
General Hospital, Edinburgh. The researchers measured levels of
inflammatory markers (such as interleukin-6 and C-reactive protein) in the
blood at
the time of clinical assessment, or soon afterwards. Also, clinicians
assessed 6 simple clinical variables, including ability to walk unaided
and
awareness of present situation, in a stroke prognostic model to predict
patient outcome. Patients were followed up to 6 months after the stroke
onset
date. Statistical analysis of the data showed that raised levels of
several inflammatory markers were associated with a poor outcome; after
allowing
for age and other factors, only interleukin-6 showed an independent and
significant association with a poor outcome. However, addition of
interleukin-6 to an existing model for stroke prognosis did not
sufficiently improve prediction of outcomes in this cohort to be useful.
Peter
Sandercock, one of the authors of the study at the University of Edinburgh
says, ""We had hoped these blood tests would help us give better advice
on whether a stroke patient might recover or not. Although the results
haven't fulfilled that promise, they do indicate that inflammation may be
an
important target to pursue in the search for new treatments for stroke."
In an accompanying Perspective also published in PLoS Medicine, Leonard
Kritharides (not involved in the research) from the University of Sydney,
Australia, comments that the study "reassures clinicians" that existing
simple clinical prognosis models give meaningful predictions of outcome
after stroke.
Funding:
William Whiteley is supported by a Chief Scientist's Office
Clinical Academic Training Fellowship from the Scottish Government. CS was
supported by a Clinician Scientist Award from the Wellcome Trust
(063668/Z/01/A) and is now funded by the Scottish Funding Council. CJ was
supported
by the Wellcome Trust (063668/Z/01/A) and now holds a Binks Trust Research
Fellowship. The funders had no role in study design, data collection and
analysis, decision to publish, or preparation of the manuscript
Citation:
"Inflammatory Markers and Poor Outcome after Stroke: A Prospective Cohort Study and Systematic Review of Interleukin-6."
Whiteley W, Jackson C, Lewis S, Lowe G, Rumley A, et al. (2009)
PLoS Med 6(9): e1000145. doi:10.1371/journal.pmed.1000145
Source
PLoS Medicine