American Stroke Association Meeting Report - See Embargo times below
February 01, 2012
NOTE ALL TIMES ARE CENTRAL. ALL TIPS ARE EMBARGOED UNTIL THE TIME OF PRESENTATION OR 3 P.M. CT/4 P.M. ET EACH DAY, WHICHEVER COMES FIRST. For more information Feb. 1-3, call Karen Astle, Bridgette McNeill, Julie Del Barto or Carrie Thacker at the New Orleans Convention Center at (504) 670-6010. Before or after these dates, call the Communications Office in Dallas at (214) 706-1396. For public inquiries call (800) AHA-USA1 (242-8721).
7:30 a.m. CT - Abstract 8
Pediatric cancer patients' stroke risk increases after treatment with cranial radiation, an effect that is dose dependent and increases with age
In a multi-institutional study of 14,358 child cancer patients and 4,023 sibling controls, 292 survivors reported a late occurring stroke.
Almost 43 percent of those occurred in brain tumor survivors, who only constituted 13 percent of participants.
Cranial radiation therapy increased stroke risk in a dose dependent manner and cumulative stroke incidence continued to rise decades after the cancer diagnosis. Modifiable risk factors such as hypertension and diabetes further increased this risk.
7:30 a.m. CT - Abstract 9
Cranial radiation therapy for cancer increases children's risk of stroke
Children undergoing cranial radiation for cancer have a higher risk of first and recurrent strokes, according to new research.
Researchers reviewed medical charts of participants, performed phone interviews to measure first and recurrent stroke and confirmed the strokes through imaging review when available.
They found:
The rate of first stroke was 594 per 100,000 person years in children who underwent cranial radiation therapy.
Seventeen first strokes occurred among the 321 participants. Males had a four-times higher risk of first stroke compared to females.
Race and chemotherapy didn't affect stroke risk. The dose effect of cranial radiation therapy couldn't be assessed due to a narrow dose range in the study.
The risk of stroke persisted for decades after treatment. Five recurrent strokes occurred at a median of six months after the first stroke.
The incidence of recurrent stroke was 21 percent at one year post first stroke, 29 percent at five years and 43 percent at 10 years.
Further studies are required to identify predictors and design secondary stroke prevention strategies, researchers said.
9:15 a.m. CT - Abstract 36
Parental stroke may predict brain aging risk in offspring
The offspring of parents who had a stroke before age 65 often show vascular changes and brain aging in middle age that can occur before clinical stroke, researchers report.
The study included 1,297 Framingham offspring, mean age 61 years. Almost 10 percent had one parent or both who had experienced a stroke before age 65.
The offspring had higher white matter hyperintensity volumes (WMHV), lesions that appear as bright spots on magnetic resonance imaging, and lower visuospatial memory (VRd) scores. VRd tests memory for objects presented visually.
Furthermore, the offspring were 1.87 times more likely to be in the highest quintile of increases in WMHV as well as to experience a worsening of executive function, a set of mental processes that allow planning and attention.
Parental stroke was not associated with total and regional brain volumes or with verbal memory, abstract reasoning and verbal learning.
The effects on baseline WMHV and VRd were equivalent to 2.8 and 7 years of brain aging, respectively, researchers said.
Magnetic resonance imaging determined total cerebral and regional brain volumes, WMHV and covert brain infarcts. Researchers tested verbal memory, abstract reasoning, verbal learning and visuospatial memory. They compared results for offspring with and without a parental history of stroke with a follow-up of six years. All were asymptomatic for stroke.
10:15 a.m. CT - Abstract 41
Epilepsy common among children who have stroke
Children who have a stroke - especially those who experience seizures at the onset - have a high risk of developing epilepsy in the next decade, according to a new study.
In a study of 371 children with stroke, researchers found that 36 percent had an acute seizure at the time of the acute stroke symptoms and 66 percent had a neurological deficit at hospital discharge.
At a median follow-up of 4.5 years, 89 subjects had post-stroke epilepsy. Average annual incidence of epilepsy was 6.4 percent with a five-year cumulative risk of 25 percent and a 10-year cumulative risk of 40 percent.
Children who had a neurologic deficit at hospital discharge had 1.8 times the risk of epilepsy and those who had a seizure during their stroke had four times the risk of epilepsy.
The population-based study included children enrolled in the Northern California integrated healthcare system whose stroke occurred from birth to age 20.
Two neurologists, and arbitration by a third, confirmed epilepsy diagnosis.
Future studies are needed to identify children at greatest risk for post-stroke epilepsy, researchers said.
3 p.m. CT - Abstract 82
Blood test helps pinpoint diagnosis of acute stroke
A blood biomarker may efficiently differentiate intracerebral hemorrhage from cerebral ischemia in patients with acute stroke, researchers reported.
Brain-specific glial fibrillary acidic protein (GFAP) is released rapidly during intracerebral bleeding and gradually in cerebral ischemia.
In a study of 205 patients at 14 stroke centers in Germany and Switzerland, researchers found that GFAP plasma concentrations were much higher in patients with intracerebral hemorrhage (mean 1.91 micrograms/liter) than those with cerebral ischemia (.08 µg/l) or stroke mimic.
Researchers drew and tested the patients' blood for GFAP during the first 4.5 hours of symptom onset. Diagnostic accuracy for GFAP differentiating intracerebral hemorrhage from other acute strokes was high. A GFAP cut-point of .29 µg/l provided a sensitivity of 84 percent and a specificity of 96 percent.
If the GFAP blood test is applied as a point-of-care measure in the pre-hospital setting, it could optimize triage of patients with symptoms of acute stroke, researchers said.
Note: Actual presentation is 4:48 p.m. CT, Wednesday, Feb. 1, 2012.
3 p.m. CT - Abstract 1947
Lack of 9-1-1 calls results in poor stroke outcome in Hispanics
Hispanics in San Diego have about half the odds of a favorable outcome after acute stroke compared to non-Hispanics - in large part because they don't use emergency medical services, researchers said.
In a University of California San Diego study, researchers found:
Only about 29 percent of Hispanics had a favorable 90-day outcome versus 40 percent of non-Hispanic stroke patients.
Hispanic patients were less likely to arrive by ambulance, with only 73 percent versus 83 percent of non-Hispanic whites using emergency medical services.
There was no difference in time of stroke onset and arrival or treatment decision. Hispanic stroke patients also were younger, more apt to be female and have diabetes.
After adjustments for stroke complications, the odds of a favorable outcome for Hispanic patients was about half that of non-Hispanic patients.
The study included 192 Hispanic and 925 non-Hispanic patients who received stroke care at five hospitals in San Diego. Researchers collected socio-demographic, clinical, discharge and day-90 data on acute ischemic stroke patients.
Strategies to boost the use of emergency medical services may decrease the disparity of stroke outcome between Hispanics and non-Hispanic whites, researchers said.
Note: Actual presentation is 6:15 p.m. CT, Wednesday, Feb. 1, 2012.
3 p.m. CT - Abstract 2212
Vitamin D may protect against stroke, cognitive impairment
Eating sufficient amounts of vitamin D may help ward off stroke and cognitive impairment, Alabama researchers report.
Participants with higher levels of vitamin D in their diets, when compared to those with lower levels, had an associated 11 percent reduction in stroke and a 24 percent reduction in cognitive impairment after adjustment for age, race, income, education, hypertension, diabetes, high cholesterol, heart disease history and weight.
The REGARDS (Reasons for Geographic and Racial Differences in Stroke) study was comprised of 30,239 black and white participants, 45 years and older. Participants were surveyed every six months for strokes and cognitive functioning was assessed annually over five years.
Researchers measured vitamin D, found in foods such as eggs, tuna and salmon, using a food frequency questionnaire and then categorized them into tertiles. Those with previous stroke or cognitive impairment were excluded.
Clinical trials should be conducted to evaluate the potential of vitamin D as a neuroprotectant, researchers said.
Note: Actual presentation is 5:55 p.m. CT, Wednesday, Feb. 1, 2012.
3 p.m. CT - Abstract 2591
Lack of sunlight may increase stroke risk
A new study found that people who lived in areas with the least sunlight during the year had the highest risk of stroke.
After adjustment for other risk factors, those who experienced sunlight exposure below the median had a 1.6 higher risk of stroke. Extreme temperatures also were linked to an increased stroke risk.
Researchers obtained data from 16,606 participants in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study. The participants were interviewed by phone, in-home evaluations and a self-administered questionnaire for residential histories since birth.
Researchers merged a 15-year residential history with satellite and ground monitor data to determine sunlight and temperature exposure.
They used 15-, 10-, five-, two- and one-year exposures to predict stroke incidence. Over an average of five years of follow-up, 351 participants had a stroke.
The study is the first to show an association between sunlight and stroke. Researchers also confirmed the results of other studies that linked cold temperatures to an increased risk of stroke.
Future research may reveal whether the finding stands and whether it's due to short- or long-term exposure, researchers said.
This study was funded by the National Institutes of Health/National Institute of Neurologic Disorders and Stroke.
Note: Actual presentation is 6:15 p.m. CT, Wednesday, Feb. 1, 2012.
3 p.m. CT - Abstract 3670
Researchers use manufacturing techniques to reduce transfer time to stroke centers
Employing techniques often used in manufacturing, St. Louis researchers have implemented a system that allows stroke patients to be rapidly transferred to comprehensive stroke centers in a more efficient and timely manner.
After implementing the new protocol:
The average time to patient acceptance for transfer decreased from 14 minutes to 9 minutes.
Patients accepted within 15 minutes increased from 186 to 307 during the first four months.
Ninety-two percent of stroke patients were accepted into the comprehensive center within 15 minutes, compared to only 73 percent previously.
Lean performance management engineers, physicians and call center staff evaluated the chain of events required to accept a patient for transfer from the outlying hospitals.
Researchers assessed barriers such as inefficient distribution of cases, calls frequently transferred from one physician to another and lack of available beds. The new system alternated calls between neurology and neurosurgery, immediate acceptance of stroke patients with behind-the-scenes allocation to the appropriate service and direct involvement of patient placement services in the transfer process.
Note: Actual presentation is 6:15 p.m. CT, Wednesday, Feb. 1, 2012.
3 p.m. CT - Abstract 3776
New drug - apixaban - shown to be more effective than aspirin in reducing the recurrence of stroke in TIA or stroke patients with atrial fibrillation
Apixaban, a new oral anticoagulant, was more effective than aspirin in reducing the risk of stroke and systemic embolism in atrial fibrillation patients who have already suffered a stroke or transient ischemic attack (TIA) and are unsuitable for warfarin therapy - the usual treatment for preventing stroke, researchers said.
These results are from the Apixaban versus Acetylsalicylic Acid to Prevent Strokes in Atrial Fibrillation Patients Who Have Failed or Are Unsuitable for Vitamin K Antagonist Treatment (AVERROES) Study.
The AVERROES study included 5,599 patients (aver. age 70) with atrial fibrillation who were unsuitable for treatment with vitamin K antagonists. Apixaban is a type of anticoagulant drug called a Factor Xa inhibitor. Researchers randomized participants to receive either five milligrams apixaban twice daily or 81 to 324 milligrams aspirin daily. Average time of follow-up was about one year.
A subgroup of patients was studied to compare apixaban in patients with (n=764) and those without (N=4,832) prior TIA or stroke.
They found in patients with prior stroke:
Only 10 participants (2.39 percent/year) with prior transient ischemic attack and stroke treated with apixaban had stroke or systemic embolism, while 33 participants (9.16 percent/year) randomized to aspirin had stroke of systemic embolism.
Nine ischemic strokes occurred in the apixaban group compared to 27 in the aspirin group.
Hemorrhagic stroke occurred in one patient on apixaban and four on aspirin.
Overall, these results translated to a number needed to treat with apixaban versus aspirin of 17 in stroke patients compared to 67 in patients without prior stroke or transient ischemic attack.
Note: Actual presentation is 6:10 p.m. CT, Wednesday, Feb. 1, 2012.
3 p.m. CT - Abstract 3781 (see related 89)
Excessive worrying, pessimism, fear, fatigue associated with increased stroke risk
Harm avoidance - including excessive worrying, pessimism, fear and fatigue - may increase your risk of stroke, researchers said.
The researchers gave the 35-item Harm Avoidance Scale to 1,082 older persons without dementia. During 3.5 years of follow-up, 258 patients died, of whom 80 percent underwent brain autopsy.
Researchers found:
High levels of the harm avoidance trait were associated with a doubling of the likelihood of stroke, with a 2.4 times higher risk of microscopic stroke and 1.8 times higher risk of an easily visible stroke. High levels included scores of 17 or in the 75th percentile or above.
In a postmortem examination of 192 older persons with harm avoidance, 45 had chronic microscopic strokes and 66 had chronic and easily visible strokes.
The associations persisted after controlling for cognitive and motor function, cardiovascular risk factors and conditions, or neuroticism.
The mechanism appears to be independent of known cardiovascular risk factors and warrants further study, researchers said.
Note: Actual presentation is 6:15 p.m. CT, Wednesday, Feb. 1, 2012
3 p.m. CT - Abstract 89 (see related 3781)
Post-stroke fatigue may be a symptom of underlying anxiety disorder
There is a known correlation between depression and fatigue. However, in a new study, researchers found that in contrast anxiety is also a fairly strong predictor of fatigue.
Forty percent of the 94 stroke patients studied experienced fatigue. Almost 15 percent had anxiety scores over 10 on the Hospital Anxiety and Depression Scale and 22 percent had scores between 8 and 10, which indicates high anxiety and borderline anxiety, respectively.
Furthermore, 6.4 percent had abnormal depression scores and 10.6 percent had borderline abnormal scores. Severity of anxiety was strongly associated with both anxiety and depression but more subjects suffered symptoms of anxiety.
"Although fatigue is a distressing symptom for many stroke survivors there is currently not an effective treatment, but there are treatments for anxiety," said Joseph Harbison, lead researcher of the study. "So if anxiety is an underlying cause, we may now have a potential intervention. However, more research is needed to confirm this association."
Note: Actual presentation is 4:48 p.m. CT, Wednesday, Feb. 1, 2012
3 p.m. CT - Abstract 4466
Hands-free ultrasound headframe device safely opens arteries in preliminary tests
A new hands-free ultrasound device called the Clotbust ERTM safely opened blocked brain arteries as effectively as a hand-held device that requires a specially-trained operator, in a study presented at the American Stroke Association's International Stroke Conference 2012.
In Combined Lysis of Thrombus in Brain Ischemia With Transcranial Ultrasound and Systemic T-PA- Hands-Free (CLOTBUST-HF), 20 people with ischemic stroke caused by large clots were treated with standard dose intravenous tPA and two hours of transcranial ultrasound delivered via the Clotbust ERTM device to the major proximal arteries that supply blood to the brain. None of the patients developed symptomatic intracerebral hemorrhage, the primary endpoint in the phase II study.
After two hours, eight of 20 patients' (40 percent) vessels were completely reopened and two of 20 (10 percent) partially reopened. The 40 percent compares favorably with the 38 percent reopening achieved in previous studies of the hand-held device and 13 percent with tPA alone.
The highest recanalization rate of 57 percent (eight of 14) occurred in patients with blockage of the middle cerebral artery.
At three months, 25 percent of the patients had completely recovered or had minimal residual symptoms with no disability, the researchers said.
The device has recently received the CE mark approval in Europe and will be further evaluated in a planned phase three trial comparing it to sham ultrasound plus tPA. Based on its design, the device can be rapidly deployed outside of stroke centers in standard emergency departments without specially-trained personnel, researchers said.
(Actual presentation is 6:15 p.m. CT, Wednesday, Feb. 1, 2012.)
###
Statements and conclusions of study authors that are presented at American Stroke Association scientific meetings are solely those of the study authors and do not necessarily reflect association policy or position. The association makes no representation or warranty as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing science content. Revenues from pharmaceutical and device corporations are available at www.heart.org/corporatefunding. External link
NR12-1008 (ISC 2012/ Wednesday tips)
Additional resources:
All downloadable video/audio interviews, B-roll, animation and images related to this news release are located on the right column of the release link located at http://newsroom.heart.org/pr/aha/_prv-sleep-apnea-linked-to-silent-strokes-221516.aspx. Video clips with researchers/authors of studies will be added to this link after embargo. General ISC video and ISC photos will be updated during the meeting at newsroom.heart.org/ISC12-Video or newsroom.heart.org/ISC12-Photos.
Follow news from ASA International Stroke Conference 2012 via Twitter: http://twitter.com/#!/heartnews External link . Follow #ASANews12.
CONTACT:
ASA News Media Office in Dallas: (214) 706-1396
ASA News Media Office in New Orleans (Feb. 1-3): (504) 670-6010
For Public Inquiries: (800) AHA-USA1 (242-8721)