A large trial that examined the effects of lowering blood pressure in the acute phase of stroke found that treatment is ineffective at preventing vascular events and poor functional outcome, according to late-breaking science presented at the American Stroke Association's International Stroke Conference 2011.

"We had anticipated that careful blood pressure-lowering with candesartan would be beneficial for patients with acute stroke and high blood pressure, but we found no beneficial effects whatsoever," said researchers Eivind Berge, M.D., Ph.D. and Else Charlotte Sandset, M.D. at the Trial Coordinating Centre at Oslo University Hospital Ulleval in Oslo, Norway.

Elevated blood pressure is common in acute stroke and is associated with a poor prognosis after stroke, but the effect of treating it in the midst of an acute stroke is unclear. While current guidelines do not recommend that blood pressure be lowered during a stroke, it is sometimes attempted.

This study, the Scandinavian Candesartan Acute Stroke Trial (SCAST), is the largest randomized-controlled clinical trial on the matter to date. Patients were randomly assigned to receive either candesartan (a blood pressure-lowering drug) or placebo once daily for seven days, with doses of candesartan/placebo gradually increasing from 4 to 16 milligrams over the first three days. Treatment began within 30 hours of stroke symptoms, and follow-up was six months. On day seven the average blood pressure was 147/82 mm Hg in the candesartan group and 152/84 mm Hg in the placebo group.

The study showed that patients who received candesartan were more likely than those who received placebo to suffer poor outcome six months after treatment, but the difference was not statistically significant, said Berge, principal investigator in the Department of internal medicine, at Oslo University Hospital Ulleval, Oslo, Norway. The number of patients who experienced a vascular event (another stroke, myocardial infarction, or death due these or other vascular events) was nearly the same in both groups.

More than two thousand (2,029) ischemic and hemorrhagic stroke patients in nine North-European countries were enrolled in the study from June 2005 to February 2010. Participants' average age was 71, the average blood pressure was 172/91 mm Hg, and patients were enrolled on average 18 hours after onset of stroke. Eighty-five percent had suffered a type of stroke caused by blockage in the brain's blood vessels (ischemic stroke); other participants had stroke due to a burst blood vessel (hemorrhagic stroke).

"Up until now there have been no large trials to inform practice in this area," he said. Previous animal studies and one clinical study suggested that candesartan treatment could help prevent vascular events when given in the acute phase of stroke. In view of these studies, this study's findings were somewhat surprising, according to Berge.

"There is no indication to lower blood pressure routinely in the acute phase of stroke, at least in the sort of patients whom we have treated, and with the type of drug that we have used," he said. "But we think that the result is applicable to other settings, and that there is no indication at the moment to lower blood pressure routinely in the acute phase stroke."

Co-authors are Else C Sandset, M.D.; Gordon Murray, M.D., Ph.D.; Philip Bath, M.D., Ph.D.; Gudrun Boysen, M.D., Ph.D.; Dalius Jatuzis, M.D., Ph.D. ; Janika Kõrv, M.D., Ph.D.; Stephan Lüders, M.D., Ph.D..; Przemyslaw Richter, M.D., Ph.D.; Risto O. Roine, M.D., Ph.D.; Andreas Terént, M.D., Ph.D.; and Vincent Thijs, M.D., Ph.D, and Eivind Berge, M.D., Ph.D.. Author disclosures are on the abstract.

The Norwegian Health Authorities, AstraZeneca and Takeda Pharmaceutical Co., Ltd. funded the study.

The trial will be simultaneously published in The Lancet.

Source:
American Heart Association, Inc.