Comprehensive stroke centers typically have 24-hour access to neurosurgery and neurologic intensive care.
The study, published in the Journal of the American Heart Association, was conducted to assess the mortality rates of patients with different forms of hemorrhagic stroke - caused by bleeding in the brain - admitted to different treatment centers. Around 13% of all strokes are hemorrhagic strokes.
"Clinicians, especially emergency-room physicians, need to be aware of the severity and potential implications of hemorrhagic stroke and try to transfer patients to the hospital most capable of providing the full complement of care," states Dr. James S. McKinney, an assistant professor of neurology at the Rutgers-Robert Wood Johnson Medical School in New Brunswick, NJ.
The researchers wanted to compare mortality rates for two different forms of hemorrhagic stroke. Subarachnoid hemorrhages are caused by bleeding after the rupture of a weakened or ballooning-out blood vessel, whereas intracerebral hemorrhages are caused by a rupture of tiny arteries within the brain tissue.
Previous research has demonstrated that treatment given by specialized stroke units and stroke centers can reduce mortality for patients with ischemic stroke - the other main form of stroke, caused by blood clots. The study authors believe that the medical and surgical care given by these units could also improve patient outcomes after hemorrhagic stroke.
Comprehensive stroke centers are usually able to offer neurologic intensive care and round the clock access to neurosurgery. Units such as these are typically staffed by specialists and trained personnel who are well-equipped to treat hemorrhagic strokes alongside other forms of bleeding in the brain.
For the study, the authors analyzed the 90-day survival of 36,981 hemorrhagic stroke patients treated at 87 hospitals in New Jersey from 1996-2012. Of these patients, 40% were treated at centers that were designated as comprehensive stroke centers by 2012.
Other patients were treated at either non-stroke centers or primary stroke centers. Primary stroke centers are equipped to deal with ischemic strokes and deliver clot-dissolving medication but may not be equipped for higher level acute neurosurgical emergencies.
Study authors recommend transfers for patients following an appropriate diagnosis
The study authors found that treatment at comprehensive stroke centers was associated with a 7% reduced risk of death for patients with all forms of hemorrhagic stroke. Specifically, treatment at these units was associated with a 27% reduced risk of death for patients with subarachnoid hemorrhage but no difference in risk for patients with intracerebral hemorrhage.
"When a person is diagnosed with a hemorrhagic stroke, loved ones should ask about the possibility of a transfer," says Dr. McKinney, the lead author of the study.
The study also demonstrated a survival advantage for patients who were transferred to comprehensive stroke centers within 24 hours of diagnosis at primary care centers or non-stroke centers. These patients were 36% less likely to die within 90 days of their stroke compared with those who were not transferred.
"The most severe patients may have been more likely to be taken to a comprehensive stroke center initially, or conversely, sicker patients at other hospitals may have been less likely to be transferred if they were already in a coma and unlikely to survive," Dr. McKinney suggests.
Unmeasured variables, the authors acknowledge, such as the severity of the strokes and the underlying neurological conditions of the patients, may have influenced the findings of the study. Additionally, some of the data were obtained prior to the designation of the units as comprehensive stroke centers.
"Further study, particularly utilizing patient-level data sets to account for stroke severity, is warranted to confirm these findings," conclude the authors.
With case fatality rates for hemorrhagic strokes at around 40-50% according to the authors, the study's findings emphasize the importance of having easily accessible comprehensive stroke centers
Unfortunately, research conducted earlier this year suggests that many people may not have rapid access to comprehensive stroke centers. The study, published in Neurology also suggests that one third of Americans would be unable to access a primary stroke center within 1 hour if they needed to.