Author Interviews, Stroke, Technology / 23.02.2017

MedicalResearch.com Interview with: Michel Piotin, MD PhD Principal investigator and Interventional Neuroradiologist Rothschild Fondation Hospital, Paris  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Mechanical thrombectomy (MT) with a stent retriever (SR), in association with intravenous rtPA, is now the standard of care in anterior circulation ischemic stroke caused by large vessel occlusion Thrombectomy (MT) with a stent retriever (SR), in association with intravenous (IV) rtPA, is now the standard of care in anterior circulation ischemic stroke caused by large vessel occlusion. Favorable outcome is strongly associated with the successful reperfusion status. New techniques for MT such as ADAPT (A Direct first pass Aspiration Technique) is promising to increase reperfusion status and clinical outcome in retrospective studies. Our study objective was to determine which technique should be used in frontline strategy (ADAPT or Stent Retriever) to achieve maximum reperfusion. The ASTER study is the first independent large randomized controlled trial focusing on ADAPT technique with blinded assessment data. (more…)
AHA Journals, Author Interviews, Technology / 23.02.2017

MedicalResearch.com Interview with: Ricardo A Hanel, MD PhD Endovascular and Skull Base Neurosurgery Director, Baptist Neurological Institute Endowed Chair, Stroke and Cerebrovascular Surgery Jacksonville, FL MedicalResearch.com: What is the background for this study? What are the main findings? Response: Medtronic Pipeline Embolization Device has been approved for carotid artery aneurysms over 10mm in size, from the petrous to clinoid segment but given the efficacy of results on these larger lesions, it has been widely utilized for treatment of smaller lesions. PREMIER came from the need of assessing the results , safety and efficacy, of pipeline for use of aneurysms under 12mm, located on the carotid artery, all segments, and V3 segment of the vertebral artery. PREMIER enrolled 141 patients treated at 22 centers (21 US, 1 Canada). Primary Safety effectiveness defined as total aneurysm occlusion, core lab adjudicated , at 1 year was 83.5%; with safety endpoint of major stroke/death at 30 days of 1.4% (2 patients), with 1-year major stroke and death rate of 2.1%. (more…)
Author Interviews, Heart Disease, JAMA, Neurological Disorders, Stroke / 13.02.2017

  Christopher Chen, FRCP Department of Pharmacology Yong Loo Lin School of Medicine Memory Aging and Cognition Center National University Health System Singapore Saima Hilal, PhD Department of Pharmacology, National University of Singapore Department of Radiology, Epidemiology and Nuclear Medicine Erasmus Medical Center, Rotterdam, the Netherlands     MedicalResearch.com Interview with: Christopher Chen, FRCP Department of Pharmacology Yong Loo Lin School of Medicine Memory Aging and Cognition Center National University Health System Singapore Saima Hilal, PhD Department of Pharmacology, National University of Singapore Department of Radiology, Epidemiology and Nuclear Medicine Erasmus Medical Center, Rotterdam, the Netherlands MedicalResearch.com: What is the background for this study? Response: Cerebral microinfarcts (CMIs) are defined as small (usually <1 mm) regions of ischemic change found in the brain which are not readily visible on gross examination or on standard 1.5-T magnetic resonance imaging (MRI). On microscopy they appear as foci of neuronal loss, gliosis, pallor, or cysts. Previous post mortem studies have shown that the presence of CMIs is relatively common in elderly individuals without dementia (24%) but more common in patients diagnosed with Alzheimer disease (43%) or vascular dementia (62%). Whilst a single CMI is likely to be “silent” as the region of brain affected is probably too small to produce symptoms or neurologic deficits, however, as a large number of CMIs exist in many individuals, especially in the cerebral cortex and watershed areas, the overall effect has clinical importance – as shown by neuropathologic studies which demonstrate an important role of CMIs in cognitive dysfunction and dementia. However in vivo studies have been hampered by the inability to detect CMIs reliably on neuroimaging, leading to CMIs being termed “invisible” during life. The advent of high spatial-definition 7-T MRI enabled the identification of cortical  Cerebral microinfarcts in-vivo and importantly a study that directly compared 7-T and 3-T MRIs in the same patients reported that 3-T MRI detected about 1/3 of the lesions found on 7-T MRIs, suggesting that 3-T MRIs, which are more accessible than 7-T, may be able to detect larger cortical CMIs with a lower limit of approximately 1 mm in diameter. Our group has made major contributions recently on the clinical associations of 3T MRI detected cortical CMIs in patients from memory clinics as well as in community based subjects. Associations were found with age, vascular risk factors, other MRI markers of cerebrovascular disease as well as cognition. However, the causes of CMIs remain unclear and may be heterogeneous with microembolism, microthrombosis, and foci of inflammation as possible causative factors. (more…)
Author Interviews, BMJ, Brigham & Women's - Harvard, Pain Research, Stroke / 13.01.2017

MedicalResearch.com Interview with: Dr. Matthias Eikermann, MD, PhD Associate Professor of Anaesthesia Harvard Medical School Clinical Director, Critical Care Division  MedicalResearch.com: What is the background for this study? Response: Up to one fifth of the general population have migraine, a primary, chronic-intermittent headache disorder affecting the neuronal and vascular systems and characterized by severe headache accompanied by nausea and/or sensory hypersensitivities such as photophobia and phonophobia. In approximately 20-30% of patients, the headache phase is preceded or accompanied by transient focal neurological disturbances presenting as visual symptoms but also sensory, aphasic, or motor symptoms known as migraine aura. Stroke is responsible for approximately 6.2 million deaths a year and is a leading global cause of long term disability. Considering that more than 50 million patients in hospital and 53 million ambulatory patients undergo surgical procedures in the United States every year. We found that patients with migraine, particularly migraine with aura, undergoing a surgical procedure are at increased risk of perioperative ischemic stroke and readmission to hospital within 30 days after discharge. (more…)
Author Interviews, Emergency Care, JAMA, Stroke, Surgical Research / 13.01.2017

MedicalResearch.com Interview with: Vitor Mendes Pereira MD MSc Division of Neuroradiology - Joint Department of Medical Imaging Division of Neurosurgery - Department of Surgery Toronto Western Hospital - University Health Network Associate Professor of Radiology and Surgery University of Toronto  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Our study is a pooled analysis of two large prospective stroke studies that evaluated the effectiveness of mechanical thrombectomy (MT) using one of the stent retrievers (Solitaire device ) in patients with acute ischemic stroke related to large vessel occlusion(LVO). It is known (after 5 randomized controlled trials in 2015) that IV rtPA alone failed to demonstrated benefit when compared to MT associated or not to rtPA. A question is still open: what it is the real benefit of IV rtPA in the context of LVO, particularly in centres that can offer mechanical thrombectomy within 60 minutes after qualifying imaging? (more…)
AHA Journals, Author Interviews, Duke, Social Issues, Stroke / 19.12.2016

MedicalResearch.com Interview with: Matthew E. Dupre, Ph.D. Associate Professor Department of Community and Family Medicine & Duke Clinical Research Institute (DCRI) Duke University MedicalResearch.com: What is the background for this study? What are the main findings? Response: There have been a handful of recent studies showing how divorce and widowhood increase one’s risk of suffering a serious health event such as a heart attack or stroke. Our research is the first to show that an individual’s marital history can have significant consequences for their prognosis after having a stroke. We found that people who never married and those with a history of marital loss were significantly more likely to die after suffering a stroke than those who were stably married. We also found that adults who experienced more than one divorce or widowhood in their lifetime were about 50% more likely to die after having a stroke than those in a long-term stable marriage. We were also somewhat surprised to find that remarriage did not seem to reduce the risks from past marital losses. (more…)
Author Interviews, Depression, JAMA, McGill, Pharmacology, Stroke / 09.12.2016

MedicalResearch.com Interview with: Christel Renoux, MD, PhD Assistant Professor, Dept. of Neurology & Neurosurgery McGill University Centre For Clinical Epidemiology Jewish General Hospital - Lady Davis Research Institute Montreal  Canada MedicalResearch.com: What is the background for this study? Response: Selective serotonin reuptake inhibitors (SSRIs) increase the risk for abnormal bleeding, in particular, gastrointestinal tract bleeding. Previous studies also suggested an increased risk for intracranial hemorrhage (ICH) in patients treated with SSRIs compared to non users. However, even if this risk exists, the comparison with a non-treated group may exaggerate the strength of a potential association and the comparison with a group of patients treated with other antidepressants may help better delineate the risk. The potential bleeding effect of antidepressants is linked to the strength of serotonin inhibition reuptake, and antidepressants that are strong inhibitors of serotonin reuptake have been associated with the risk for gastrointestinal or abnormal bleeding compared with weak inhibitors but the risk of ICH is unclear. (more…)
Author Interviews, CMAJ, Heart Disease, Stroke / 27.11.2016

MedicalResearch.com Interview with: Dr. Tony Antoniou, PhD Research Scholar Department of Family and Community Medicine and a Scientist Keenan Research Centre of the Li Ka Shing Knowledge Institute St. Michael's Hospital Assistant Professor in the Department of Family and Community Medicine and Leslie Dan Faculty of Pharmacy University of Toronto, Toronto, Ontario MedicalResearch.com: What is the background for this study? What are the main findings? Response: Dabigatran etexilate is an anticoagulant that is commonly used for stroke prevention in patients with atrial fibrillation. Absorption of dabigatran etexilate is opposed by intestinal P-glycoprotein, an efflux transporter. Once absorbed, dabigatran etexilate is converted to its active form by carboxylesterase enzymes. Unlike other statins, simvastatin and lovastatin can inhibit P-glycoprotein and carboxylesterase. This may result in increased absorption of dabigatran etexilate, thereby increasing the risk of bleeding. Conversely, inhibition of carboxylesterase may decrease the effectiveness of dabigatran etexilate. (more…)
Author Interviews, Gender Differences, JAMA, Stroke / 19.11.2016

MedicalResearch.com Interview with: Catharina J. M. Klijn, MD Brain Center Rudolf Magnus, Department of Neurology and Neurosurgery University Medical Center Utrecht, Utrecht Donders Institute for Brain, Cognition and Behaviour, Centre for Neuroscience Department of Neurology Radboud University Nijmegen Medical Centre Nijmegen, the Netherlands MedicalResearch.com: What is the background for this study? Response: The incidence of stroke is higher in men than in women. This difference attenuates with increasing age. Established risk factors for stroke, such as hypertension, cigarette smoking and ischemic heart disease are more prevalent in men but only partly explain the difference in stroke incidence. The contribution of oral contraceptive use and hormone therapy to stroke risk has been previously reviewed. We aimed to evaluate what is known on other female- and male specific risk factors for ischemic and hemorrhagic stroke incidence and stroke mortality through a systematic review and meta-analysis of 78 studies including over 10 million participants. (more…)
Author Interviews, Columbia, JAMA, OBGYNE, Stroke / 24.10.2016

MedicalResearch.com Interview with: Eliza Miller, M.D. Vascular Neurology Fellow New York-Presbyterian Hospital/Columbia University Medical Center We collaborated with researchers at the Massachusetts General Hospital and with the New York State Department of Health. MedicalResearch.com: What is the background for this study? What are the main findings? Response: Prior research has found that older women of childbearing age are at higher risk of stroke during pregnancy and postpartum than younger women. We hypothesized that their increased stroke risk might not be due to pregnancy-related factors, but just due to the fact that stroke risk increases with age for all people. We used billing data from New York State hospitals to calculate incidence risk ratios for four age groups: 12-24, 25-34, 35-44 and 45-55. In each age group, we compared the incidence of stroke in women who were pregnant or postpartum to the incidence of stroke in women of the same age who were not pregnant. As in prior studies, we found that the incidence of pregnancy-associated stroke was higher in older women compared to younger women (about 47/100,000 deliveries in the oldest group, versus 14/100,000 deliveries in the youngest group). However, the incidence ratios showed that pregnancy increased stroke risk significantly in women under 35, but did not appear to increase stroke risk in women over 35. In the youngest group (age 12-24), pregnancy more than doubled the risk of stroke, and in the 25-34 age group, pregnancy increased stroke risk by 60%. In women aged 35 and older, pregnancy did not increase stroke risk. Women who had pregnancy-related strokes tended to have fewer traditional vascular risk factors like hypertension and diabetes, compared to same-aged women with non-pregnancy related strokes. (more…)
Author Interviews, Imperial College, Stroke, Technology / 06.10.2016

MedicalResearch.com Interview with: Dr Paul Bentley MA MRCP PhD Clinical Senior Lecturer in Clinical Neuroscience Honorary Consultant Neurologist Neurology Dept Imperial College NHS Healthcare Trust Charing Cross Hospital London MedicalResearch.com: What is the background for this study? What are the main findings? Response: gripAble was designed to help people with arm disability practise physiotherapy when a physiotherapist is not available, or in between physiotherapy sessions. We know that the amount of physiotherapy provision in the UK, after stroke or arm injury, is typically below that which is recommended by professional bodies. Furthermore, increasing research suggests that higher-intensity training can boost functional outcomes. The innovation was designed to help people with a range of disabilities including severe paralysis engage with computer games with their weak arm. At the same time its designed to be portable for use at home or in bed, and low-cost. gripAble also enables remote measurement and monitoring of arm function, by setting users a series of calibrated tasks played out on the tablet screen. This way doctors and physiotherapists can assess the needs of a patient, and gain an idea of how well a patient is responding to home physiotherapy. (more…)
Author Interviews, JAMA, Stroke / 27.09.2016

MedicalResearch.com Interview with: Dr. Michael Hill, MSc, MD, FRCPC Professor for the Departments of Clinical Neurosciences, Community Health Sciences, Medicine and Radiology University of Calgary Director of the Stroke Unit Calgary Stroke Program Alberta Health Services MedicalResearch.com: What is the background for this study? What are the main findings? Response: The HERMES collaboration is a pooled individual patient meta-analysis of recent endovascular ischemic stroke trials. The current analysis assesses the role of time to treatment and outcome. We show that there is a clear relationship between time from onset-to-treatment and outcome, with treatment gradually becoming less effective as time elapses from stroke onset. Treatment was still effect, on average, out to just beyond 7 hours from stroke onset. (more…)
Author Interviews, BMJ, Heart Disease, Stroke / 12.09.2016

MedicalResearch.com Interview with: Ayodele Odutayo, DPhil student Centre for Statistics in Medicine Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences University of Oxford, Oxford, UK MedicalResearch.com: What is the background for this study? What are the main findings? Response: Atrial fibrillation is associated with an increased risk of all cause mortality and stroke, as well as higher medical costs and a reduced quality of life. The association between atrial fibrillation and cardiovascular outcomes other than stroke is less clear. We found that atrial fibrillation is associated with a wide range of cardiovascular events, including cardiovascular mortality, major cardiovascular events, heart failure, ischaemic heart disease, chronic kidney disease, and sudden cardiac death, as well as stroke and all cause mortality. The relative and absolute risk increase associated with many of these events is greater than that of stroke. Interventions are needed to reduce the risk of non-stroke cardiovascular outcomes in adults with atrial fibrillation. (more…)
AHA Journals, Anemia, Author Interviews, Hematology, Stroke / 30.08.2016

MedicalResearch.com Interview with: Raphae Barlas M.A 3rd year MBChB student The Institute of Applied Health Sciences Aberdeen MedicalResearch.com: What is the background for this study? What are the main findings? Response: Anemia and stroke are both common conditions. While previous studies have found an association between anemia on admission and increased mortality in stroke patients, this was not consistent throughout the literature. We aimed to comprehensively assess this association by conducting our own observational study, consisting of 8000 patients from UK regional stroke registry data. We then aggregated our findings into a systematic review and meta-analysis of the existing literature for a total study population of approximately 30,000 patients. (more…)
Author Interviews, Neurology, Stroke / 29.08.2016

MedicalResearch.com Interview with: Dr. Ashkan Shoamanesh MD FRCPC Assistant Professor Division of Neurology, Department of Medicine McMaster University and Dr. Jose Rafael Romero, MD Associate Professor of Neurology Boston University School of Medicine MedicalResearch.com: What is the background for this study? What are the main findings? Response: The Framingham Heart Study is a population-based study of individuals residing in the community. Identifying people who are at risk for stroke can help us determine who would benefit most from existing or new therapies to prevent stroke. As inflammatory pathways are believed to contribute to vascular disease and stroke, we tested whether circulating biomarkers of inflammation and endothelial dysfunction could improve the predictive ability of the Framingham Stroke Risk Profile score, a model that contains classical vascular risk factors such as high blood pressure and diabetes. Our main observation was that inclusion of 4 biomarkers (C-reactive protein, tumor necrosis factor receptor-2, total homocysteine, and vascular endothelial growth factor) in the Framingham Stroke Risk Profile improved its ability to predict a stroke (net reclassification improvement of 0.34 [0.12–0.57]). (more…)
Author Interviews, Ophthalmology, Stroke / 15.08.2016

MedicalResearch.com Interview with: Rong-Kung Tsai MD, PhD Professor and Director Institute of Eye Research Buddhist Tzu Chi Medical Center; Director, Institute of Medical Sciences Tzu Chi University, Hualien, Taiwan MedicalResearch.com: What is the background for this study? What are the main findings? Response: Non-arteritic anterior ischemic optic neuropathy (NAION) is pathogenetically different from stroke, stroke is caused by thromboembolism. However, they share many (but not all) systemic vascular risk factors. Previous small scale studies got controversial results. Using the National Health Insurance Research Database (NHIRD) in Taiwan to conduct the cohort study, 414 patients were included in the NAION group and 789 in the control group (base one million beneficiaries). The incidence of NAION is 3.72/100,000 person-years in Taiwan, and patients with NAION have more chances to develop ischemic stroke (p=0.003), but not hemorrhage stroke. The subgroup analyses further showed the risk of ischemic stroke among the subjects with NAION and with comorbidities was 3.35 times higher than those without NAION. However, in patients with NAION but no comorbidities, there is no increase risk of stroke development. (more…)
Author Interviews, Heart Disease, JACC, Stroke, Surgical Research / 12.08.2016

MedicalResearch.com Interview with: Josep Rodés-Cabau, MD Director, Catheterization and Interventional Laboratories Quebec Heart and Lung Institute Professor, Faculty of Medicine, Laval University Quebec City, Quebec, Canada MedicalResearch.com: What is the background for this study? Response: Transcatheter aortic valve replacement (TAVR) is increasingly used in patients with severe aortic stenosis deemed at prohibitive or high surgical risk. Recently, a randomized trial demonstrated the non-inferiority of TAVR compared to surgical aortic valve replacement in intermediate risk patients for the outcome of death and disabling stroke at 2 years. Therefore, TAVR indications are likely to expand to younger and lower risk patients in the near future. While the short-term (30-day) cerebrovascular event (CVE) rate post-TAVR has decreased over time, it remains the most dreadful complication of TAVR, and still occurs in 2% to 3% of patients. A few dedicated studies identified numerous predictors of CVE which mainly differ from one study to another. However, identifying the risk factors of CVE is of paramount relevance in clinical practice to implement preventive strategies, either instrumental (embolic protection devices) or pharmacological in high-risk patients. Thus, we performed a systematic review and meta-analysis using random-effect models to provide pooled estimates of sixteen (8 patient-related and 8 procedural-related) clinically-relevant predictors of CVE within 30 days post TAVR. (more…)
Author Interviews, Heart Disease, Race/Ethnic Diversity, Stroke / 27.07.2016

MedicalResearch.com Interview with: Dr. Mary Vaughan Sarrazin PhD Associate Professor Department of Internal Medicine University of Iowa Roy and Lucille Carver College of Medicine, and Iowa City VA Medical Center, Center for Comprehensive Access & Delivery Research and Evaluation (CADRE) Iowa City MedicalResearch.com: What is the background for this study? Response: Atrial fibrillation is associated with a higher risk of stroke. The CHA2DS2VASc score (congestive heart failure, hypertension, age 75 or older, diabetes, previous stroke, vascular disease, age 65-74, female sex) reflects stroke risk and is used to guide decisions regarding anticoagulation. Our prior work suggests that African Americans have a higher risk of stroke compared to other patients with atrial fibrillation, even after risk factor adjustments. In the current study, we used Medicare data to test whether addition of black race to CHA2DS2VASc score improves stroke prediction in patients with atrial fibrillation. (more…)
Author Interviews, Health Care Systems, JAMA, Stroke / 25.07.2016

MedicalResearch.com Interview with: Kimon Bekelis, MD Chief Resident Department of Neurosurgery Dartmouth-Hitchcock School of Medicine MedicalResearch.com: What is the background for this study? Response: Physicians often must decide whether to treat acute stroke patients locally, or refer them to a more distant Primary Stroke Center (PSC). There is little evidence on how much the increased risk of prolonged travel time offsets benefits of specialized  Primary Stroke Center care. (more…)
Author Interviews, JAMA, Johns Hopkins, Race/Ethnic Diversity, Stroke / 25.07.2016

MedicalResearch.com Interview with: Romanus Roland Faigle, M.D., Ph.D. Assistant Professor of Neurology The Johns Hopkins Hospital MedicalResearch.com: What is the background for this study? Response: Stroke care entails a variety of procedures and interventions, which generally fall into one of the two following categories: 1) curative/preventative procedures (such as IV thrombolysis and carotid revascularization), which intent to prevent injury and restore function; and 2) life-sustaining procedures (such as gastrostomy, mechanical ventilation, tracheostomy, and hemicraniectomy), which intent to address complications from a stroke and to prevent death. The use of curative/preventative procedures is supported by excellent evidence and is guided by well-defined criteria, while those are largely lacking for life-sustaining procedures. Therefore, curative/preventative are desirable for eligible patients, while life-sustaining procedures indicate the need to address undesired complications and in itself have questionable utility. We wanted to determine whether race differences in the use of the individual stroke-related procedures exist, and whether presence and directionality of differences by race follow a pattern unique to each of the 2 procedure groups. (more…)
AHA Journals, Author Interviews, Gender Differences, Stroke, Tobacco Research / 23.07.2016

MedicalResearch.com Interview with: Joni Valdemar Lindbohm, MD Department of Public Health University of Helsinki, Finland MedicalResearch.com: What is the background for this study? Response: Approximately 1-6% percent of people carry an unruptured intracranial aneurysm but most of these never rupture during lifetime and cause subarachnoid hemorrhage (SAH). In SAH, the rupture of an aneurysm causes bleeding into the lining between the brain’s surface and underlying tissue. Despite advances in operative techniques, SAH can lead to death in up to 45% of the cases. Because life style risk factors are critical in development of subarachnoid hemorrhage, it is important to characterize the risk factor profile of those with an elevated risk. Widely accepted risk factors for SAH are increasing age, smoking, hypertension and female sex. However, the reasons for an elevated risk in women have remained uncovered and the effect of smoking habits are not well understood. (more…)
Author Interviews, NYU, Race/Ethnic Diversity, Sleep Disorders, Stroke, Weight Research / 09.07.2016

MedicalResearch.com Interview with: Azizi Seixas, Ph.D. Post-Doc Fellow Department of Population Health Center for Healthful Behavior Change NYU School of Medicine MedicalResearch.com: What is the background for this study? What are the main findings? Response: Compared with whites, blacks are disproportionately affected by strokes. The overwhelming prevalence of obesity among blacks compared to whites has been suggested as a possible explanation for the disproportionate rates of strokes among blacks compared to whites. Recent findings linking insufficient sleep and stroke as well as the disproportionate burden of insufficient sleep among blacks compared to whites might provide a unique mechanism explaining why blacks have higher rates of stroke. However, it is unclear whether insufficient sleep and obesity contributes to the higher rates of stroke among blacks compared to whites. To test our hypothesis, we utilized data from the National Health Interview Survey from 2004-2013 with a sample size of 288,888 individuals from the United States. Using Bayesian Belief Network (BBN) analysis, a form of machine learning analysis, we assessed the mediating effects of BMI on the relationship between short sleep duration (≤6 hrs. total sleep duration), long sleep duration (≥9 hrs. total sleep duration), and stroke, and whether race/ethnicity differences in obesity moderated these relationships. (more…)
Author Interviews, Brigham & Women's - Harvard, Race/Ethnic Diversity, Stroke / 04.07.2016

MedicalResearch.com Interview with: Nilay Kumar M.B.B.S. Attending physician at Cambridge Health Alliance, Cambridge, MA Instructor in Medicine at Harvard Medical School Boston, MA  MedicalResearch.com: What is the background for this study? What are the main findings? Response: Racial differences in stroke mortality have major health policy implications. A large body of evidence has shown significant racial differences in the incidence of stroke and associated mortality rate (death due to stroke per unit population per year) in the United States. Few studies to date have addressed racial differences in in-hospital outcomes after acute ischemic stroke using population level datasets. Previous studies have shown inconsistent results with respect to racial differences in in-hospital case fatality rate after acute ischemic stroke. Additionally, racial minorities have been known to be less likely to receive evidence based reperfusion therapies for several cardiovascular diseases including acute myocardial infarction and ischemic stroke. Previous studies on racial differences in stroke outcomes have rarely included Asian and Pacific Islanders. Against this background, we aimed to ascertain racial differences in outcomes of acute ischemic stroke hospitalization in the US using a nationally representative sample. (more…)
Author Interviews, Genetic Research, JAMA, Stroke / 28.06.2016

MedicalResearch.com Interview with: Dr. Yongjun Wang  Principal Investigator No. 6 Tiantanxili Dongcheng District, Beijing, China MedicalResearch.com: What is the background for this study? What are the main findings? Response: Clopidogrel requires conversion to an active metabolite by hepatic cytochrome p450 (CYP) iso-enzymes to exert an antiplatelet effect, and polymorphisms of the CYP2C19 gene have been identified as strong predictors of clopidogrel nonresponsiveness. However, data are limited regarding the association between CYP2C19 genetic variants and clinical outcomes of clopidogrel-treated patients with minor stroke or transient ischemic attack. The main findings of this study is that the combined treatment of clopidogrel and aspirin compared with aspirin alone reduced the risk of a new stroke only in the subgroup of patients with minor ischemic stroke or TIA who were not carriers of the CYP2C19 loss of function alleles. (more…)
Author Interviews, MRI, Neurological Disorders, Neurology, NIH, Stroke / 22.06.2016

MedicalResearch.com Interview with: Dr. Richard Leigh MD Neuro Vascular Brain Imaging Unit National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD MedicalResearch.com: What is the background for this study? What are the main findings? Response: Patients who suffer an ischemic stroke have limited treatment options. One of the reasons for this is that our treatments can sometimes make the stroke worse by transforming the ischemic stroke into a hemorrhagic stroke. In our study we identified a new piece of information that we can extract from the patient’s MRI scan that informs us on the risk of having a hemorrhage. (more…)
Author Interviews, Brigham & Women's - Harvard, CT Scanning, JAMA, Stroke / 21.06.2016

MedicalResearch.com Interview with: Dr. Gregoire Boulouis MD MS Research Fellow at Massachusetts General Hospital / Harvard Med. School Boston, Massachusetts MedicalResearch.com: What is the background for this study? What are the main findings? Dr. Boulouis: Hemorrhagic Stroke or Intracerebral hemorrhage (ICH) still has a poor prognosis. A substantial proportion of patients will experience ongoing intracranial bleeding and their hematomas will grow in size in the first hours following presentation, a phenomenon called 'hemorrhage epxansion'. Patients with hemorrhage expansion have been shown to have significantly worse clinical outcome. If all baseline ICH characteristics (location, initial hemorrhage volume, ..) are non modifiable at the time of diagnosis, hemorrhage expansion, however, represents one of the few potential targets to improve outcome in ICH patients. An accurate selection of patients at high risk of expansion is needed to optimize patients' selection in expansion targetted trials and, eventually, to help stratifying the level of care at the acute phase. In this study, we investigated whether the presence of non-contrast Computed Tomography hypodensities within the baseline hematoma, a very easily and reliably assessed imaging marker, was associated with more hemorrhage expansion. A total of 1029 acute phase ICH patients were included ; approximately a third of them demonstrated CT hypodensities at baseline. In this population, CT hypodensities were independently associated with hemorrhage expansion with an odds ratio of 3.42 (95% CI 2.21-5.31) for expansion in fully adjusted multivariable model. (more…)
Alzheimer's - Dementia, Author Interviews, Brigham & Women's - Harvard, JAMA, Stroke / 14.06.2016

MedicalResearch.com Interview with: Alessandro Biffi, MD Behavioral Neurology and Neuropsychiatry Departments of Neurology and Psychiatry Massachusetts General Hospital / Harvard Medical School MedicalResearch.com: What is the background for this study? Dr. Biffi: Intracerebral Hemorrhage (ICH) is the most severe form of stroke. It is a form of hemorrhagic (i.e. bleeding) stroke that accounts for ~ 15% of all acute cerebrovascular conditions, affecting ~ 70,000 Americans every year. However, because of its severity it is responsible for almost half of all stroke-related disability worldwide. Survivors of ICH are at very high risk for cognitive impairment (up to and including dementia) following the acute cerebral bleeding event. However, we possess very limited understanding of the time dynamics and risk factors for post-ICH dementia. In particular, prior to our study it was unclear whether the acute cerebral injury due to ICH would be the only mechanism potentially responsible for subsequent development of dementia. This question is motivated by prior observations suggesting that Intracerebral Hemorrhage represents the acute manifestation of cerebral small vessel disease, a progressive degenerative disorder of small caliber arteries of the central nervous system. There exist two major subtypes of small vessel disease: 1) cerebral amyloid angiopathy, caused by the deposition of a toxic protein product, beta-amyloid, in the blood vessels (in a process similar to the formation of beta-amyloid plaques that cause Alzheimer's disease); 2) arteriolosclerosis, caused by long-standing elevated blood pressure. ICH survivors have been previously shown to harbor very severe small vessel disease, which has been linked to dementia in patients without cerebral bleeding. Our hypothesis was that early-onset dementia (occurring in the first 6 months after ICH) is a manifestation of the acute neurological damage associated with cerebral bleeding, whereas delayed onset dementia (developing beyond 6 months from the acute ICH event) is associated with known markers of small vessel disease, including imaging findings on CT/MRI and genetic markers (such as the APOE gene). (more…)
Author Interviews, Blood Pressure - Hypertension, NEJM, Stroke / 09.06.2016

MedicalResearch.com Interview with: Adnan I. Qureshi, M.D Zeenat Qureshi Stroke Research Center University of Minnesota Minneapolis, MN MedicalResearch.com: What is the background for this study? What are the main findings? Dr. Qureshi: An acute hypertensive response in patients with intracerebral hemorrhage is common and may be associated with hematoma expansion and increased mortality. The Antihypertensive Treatment of Acute Cerebral Hemorrhage II (ATACH-2) trial was designed to determine the efficacy of rapidly lowering systolic blood pressure in patients in an earlier time window after symptom onset than evaluated in previous trials. The trial was based on evidence that hematoma expansion and subsequent death or disability might be reduced with very early and more aggressive reduction in systolic blood pressure in those at higher risk due to presence of high systolic blood pressure at presentation. The trial randomized eligible subjects with intracerebral hemorrhage to test the superiority of intensive (goal 110-140 mmHg) over standard (goal 140-180 mmHg) systolic blood pressure reduction using intravenous nicardipine within 4.5 hours of symptom onset. Of a total of 1000 subjects that were recruited with a mean (standard deviation) baseline systolic blood pressure of 200.6 (27.0) mmHg, 500 were assigned to intensive-treatment and 500 to standard-treatment. Enrollment was stopped following a pre-specified interim analysis because of futility. The primary endpoint of death or disability at 3 months post-randomization was observed in 38.7% (186/481) of subjects receiving intensive treatment and 37.7% (181/480) subjects receiving standard treatment (relative risk: 1.03; 95% confidence interval: 0.85 to 1.27), adjusted for age, initial Glasgow Coma scale, and presence or absence of intraventricular hemorrhage. The rate of renal adverse events within 7 days of randomization was significantly higher among subjects randomized to intensive treatment. Compared to a target systolic blood pressure of 140-180 mmHg, treating subjects with intracerebral hemorrhage to a target systolic blood pressure of 110-140 mmHg did not lower the rate of death or disability. (more…)
Author Interviews, Race/Ethnic Diversity, Stroke / 04.06.2016

MedicalResearch.com Interview with: George Howard, Dr.P.H. Professor of biostatistics Birmingham School of Public Health University of Alabama MedicalResearch.com: What is the background for this study? What are the main findings? Dr. Howard: What has been known for many decades is that death rates from stroke are much higher in the black than white population, particularly between the ages of 45 – 65 (or maybe even a little older). These racial differences in stroke are among the greatest disparities for any disease, clearly it is a priority to reduce this disparity. However, there are two reasons more blacks could die from a disease: 1) more blacks get the disease, or 2) once you get the disease, it is more likely to kill blacks. The implications of knowing which of these is the major contributor is profound. If the driving force is more blacks are having more stroke, then we need to focus out attention on activities before stroke occur. For example, prevention of the greater prevalence of hypertension and diabetes in blacks, and also reducing the differences in the control of blood pressure and glucose. However, if the driving force is a higher chance of death in blacks once stroke occur, then we need to focus on the disparities in how black stroke patients are cared for compared to white stroke patients. That is, the former requires community-based efforts, while the latter requires hospital-based efforts. What we found was that nearly all the difference was that blacks are having more strokes ... not that they are more likely to die once stroke occurs. (more…)