NEW ORLEANS, Feb. 22 — Early intensive treatment for high blood pressure (‘hypertension’) in patients with acute intracerebral hemorrhage is well tolerated and appears to slow the growth of hematomas, according to late-breaking science results presented at the American Stroke Association’s International Stroke Conference 2008.

A hematoma is a blood clot caused by bleeding from a ruptured vessel in the brain – intracerebral hemorrhage (ICH). Hematomas are associated with high death rates and severe disability.
Researchers in the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT) enrolled 404 patients from 44 hospitals in Australia, China and Korea in a pilot phase from November 2005 to April 2007. Each patient was at least 18 years old, had an acute intracerebral hemorrhage confirmed by a computerized tomography scan (CT scan) and had elevated systolic blood pressure of 150 to 220 millimeters of mercury (mm Hg). Each patient was able to begin treatment in a monitored environment within six hours of suffering an acute ICH. 

Patients were assigned at random to receive either intensive anti-hypertensive treatment based on a stepped protocol of routinely available intravenous agents or a less intensive treatment based on American Heart Association guidelines. The target for the former group was to reduce systolic blood pressure to 140 mm Hg while the target for the latter group was a reduction to 180 mm Hg. 

After the first hour, systolic blood pressure was an average of 13.3 mm Hg lower in the intensive group than in the guidelines group. The average hematoma growth was 22.6 percent lower in the intensive group than in the guidelines group after adjusting for the initial hematoma volume and the time from onset of the intracerebral hemorrhage to CT scan. This equated to about a half of a teaspoon (2.5ml) of less blood in the brain from the treatment. 

At the same time, the frequency of “substantial” hematoma growth – defined by ongoing bleeding of more than one third of initial volume – was 36 percent lower in the intensive group than in the guidelines group. 

After 90 days “there was no evidence that early intensive blood pressure-lowering increased the risks of serious adverse events or a poor outcome at 90 days,” the researchers reported. 

“The results of the INTERACT study show that drug treatment to lower elevated blood pressure can be given quickly and safely to patients with intracranial hemorrhage,” said lead author Craig Anderson, M.D. Ph.D., Professor of Stroke Medicine and Clinical Neuroscience of The George Institute for International Health, and The Royal Prince Alfred Hospital and University of Sydney, Australia. “Furthermore, this treatment appears to limit bleeding in the brain in this type of stroke, which may improve chances of recovery for patients.” 

He said this hypothesis will be tested in a much larger INTERACT study later this year. 

The study is funded by the National Health and Medical Research Council of Australia. 

Disclosures: The INTERACT study was funded by a grant from the National Health and Medical Research Council (NHMRC) of Australia. Professor Anderson holds an NHMRC Senior Research Fellowship and is employed by The George Institute for International Health who undertook this research independent of the NHMRC.

###

Statements and conclusions of abstract authors that are presented at American Heart Association/American Stroke Association scientific meetings are solely those of the abstract authors and do not necessarily reflect association policy or position. The associations make no representation or warranty as to their accuracy or reliability.

NR08-1025 (ISC08/LB3/Anderson) 

Note: This abstract will be presented at 11:50 a.m. CST, Fri., Feb. 22, 2008.