BOSTON -- In a real-world practice setting, the use of tissue plasminogen activator (tPA, Alteplase) results in a higher rate of intracerebral hemorrhage than was seen in the well-controlled clinical trials that led to widespread use of the treatment in stroke patients, researchers said here.
"Our rate of intracerebral hemorrhage of 15.6% was significantly greater as compared to the National Institutes of Neurological Disorders and Stroke (NINDS) tPA study group at 6.4% (P<0.05)," reported and colleagues from Wagner College in New York City.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
- In a retrospective chart review of patients with acute ischemic stroke, thrombolytic therapy was associated with a rate of intracerebral hemorrhage which was significantly greater than that observed in controlled trials of the National Institutes of Neurological Disorders and Stroke tPA study group.
At the group's poster presentation during the annual meeting of the American Academy of Physician Assistants, co-author also of Wagner College, told 鶹ý that the study included 173 consecutive patients who were treated for emergent stroke with tPA from 2006 to 2013 at the emergency department of Staten Island University Hospital.
"We think the reason we saw in our retrospective study a greater number of intracerebral hemorrhages may have been because many of the patients treated had higher NIHSS (National Institutes of Health Stroke Scale) scores at admission than [those that] were treated in the pivotal trial," Cookish said. The patients who had NIHSS score of 17 or higher were 60% more likely to bleed than individuals with a score of less than 17 on the stroke scale (P<0.001), he said.
Of the 27 patients who experienced intracerebral bleeds, 11 died -- an inhospital mortality rate of 40.7%; of the 146 patients included in the study who did not have an intracerebral hemorrhage, 0.7% died. Overall mortality was 6.9%.
Buxton told 鶹ý, "We think one of the strengths of our study was that we included all comers to give us a better idea of patient outcomes in a real practice. For example, in the clinical trials patients over 80 years of age were treated; one of our patients in our study was 97."
The researchers excluded 57 patients of the total of 230 identified in the chart review, said Joanne Comber, PA, also of Wagner. The patients were excluded if the NIHSS score was not included in the chart, if the patients suffered a stroke after being admitted for a different medical reason, or if they were transported to another facility after receiving tPA therapy at the initial hospital.
"We recommend universal implementation of the NIHSS score before thrombolytic therapy and excluding patients with severe strokes -- NIHSS 17 or greater -- from receiving thrombolytic therapy," Cookish said. He added, the chances of a person with a severe stroke deriving benefit from tPA is minimal, but the risk of making things worse appears to be high.
"I think these findings are what you would expect to see in the real world," said , associate professor and clinical coordinator of the New York Institute of Technology physician assistant studies program in Old Westbury.
"The 6.4% rate of intracerebral hemorrhage is what is seen in carefully, well-controlled patients in a pivotal clinical trial, and the 15.6% rate is what is seen in real-world settings where there may be patients entered later in the trial or people who are older than those in the trial," he told 鶹ý. Jackson was not a participant in the Wagner study.
Comber told 鶹ý that the risk of intracerebral hemorrhage did not appear to correlate with the time to treatment after first symptoms appeared. Age, a history of atrial fibrillation, and NIHSS scores appeared to correlate with intracerebral hemorrhage.
Buxton, Comber, and Cookish are recent graduates of the Wagner physician assistants studies program.
Disclosures
The researchers disclosed no relevant relationships with industry. Jackson disclosed no relevant relationships with industry.
Primary Source
American Academy of Physician Assistants
Source Reference: Buxton A, et al "Thrombolytic therapy for acute ischemic stroke: positive and negative outcomes" AAPA 2014; Abstract 448.