Factor XI Levels in Acute Ischemic Stroke
Summary
The purpose of this study is to evaluate the utility of measuring coagulation factor activities in the setting of acute ischemic stroke, as potential markers of inherited thrombotic risk. The investigators will determine if relationships exist between coagulation factors, including factor VIII, factor IX, and factor XI and clinical diagnosis, classification, and outcome. The investigators will determine if any significant elevations of these factor activities are independent thrombotic risk factors.
Null Hypothesis: There is no statistical difference between coagulation factors, including factors VIII, IX, or XI activity levels in patients having acute ischemic stroke as compared to acute stroke mimics.
Description
Increased factor XI levels have been associated with venous thromboembolic disease and acute myocardial infarction. However, checking factor XI levels is not currently indicated to assess individual thromboembolic risk. Factor XI is an important protease that links the extrinsic arm of the coagulation cascade with the intrinsic arm through dual activation by both factor XII and thrombin. Since thrombin is a downstream product of factor XI, a feedback loop is created that amplifies thrombin production and ultimately results formation of a stable fibrin clot. Sufficient thrombin generation via this pathway also contributes to activation of the Thrombin-Activatable Fibrinolysis Inhibitor (TAFI). Activated TAFI downregulates fibrinolysis and has been implicated as part of the association between elevated factor XI levels and venous thromboembolic disease. One study found that functional TAFI levels of > 120% increased the risk of ischemic stroke approximately 6-fold, however, the association between Factor XI and ischemic stroke has yet to be firmly established. We recently performed a preliminary retrospective analysis of 78 patients with stroke or transient ischemic attack (TIA) and found that patients with factor XI activity levels above the 95th percentile of an age and sex matched reference population had a relative risk of 5.3 for stroke or TIA. Factor XI measurements may be able to help identify thromboembolic disease, aiding in the determination of stroke etiology.
Study Design
Observational Model: Case Control, Time Perspective: Retrospective
Conditions
Stroke
Location
University of Utah Health Sciences Center
Salt Lake City
Utah
United States
84132
Status
Recruiting
Source
University of Utah
Results (where available)
Links
- Source: http://clinicaltrials.gov/show/NCT00890812
- Information obtained from ClinicalTrials.gov on July 15, 2010
Medical and Biotech [MESH] Definitions
Stroke
A group of pathological conditions characterized by sudden, non-convulsive loss of neurological function due to BRAIN ISCHEMIA or INTRACRANIAL HEMORRHAGES. Stroke is classified by the type of tissue NECROSIS, such as the anatomic location, vasculature involved, etiology, age of the affected individual, and hemorrhagic vs. non-hemorrhagic nature. (From Adams et al., Principles of Neurology, 6th ed, pp777-810)
Heat Stroke
A condition caused by the failure of body to dissipate heat in an excessively hot environment or during PHYSICAL EXERTION in a hot environment. Contrast to HEAT EXHAUSTION, the body temperature in heat stroke patient is dangerously high with red, hot skin accompanied by DELUSIONS; CONVULSIONS; or COMA. It can be a life-threatening emergency and is most common in infants and the elderly.
Rats, Inbred Shr
A strain of Rattus norvegicus with elevated blood pressure used as a model for studying hypertension and stroke.
Stroke Volume
The amount of BLOOD pumped out of the HEART per beat not to be confused with cardiac output (volume/time).
Sunstroke
Heat stroke caused by exposure to the sun. It is characterized by dangerously high BODY TEMPERATURE; red, hot skin; DELUSIONS; CONVULSIONS; or COMA. It can be a life-threatening emergency and is most common in infants and the elderly.
Clinical Trials
Stroke: Reduction of Physical Performance Post Stroke. Inactivity or Secondary Complications?
The purpose of this project is to follow first-ever- acute stroke patients from onset, one, two and four years post stroke and study the effect of two different approaches of exercises imp...
Measuring Health Related Quality of Life in Veterans With Stroke
Approximately 11,000 veterans annually are hospitalized with a newly acquired incident stroke. Based on American Heart Association ratios of stroke incidence and prevalence, up to 80,000...
Follow-up Pilot Study After a First Stroke
This is a randomized follow-up study after discharge from a stroke unit after a first stroke. The patients are randomized either to follow-up at a special out-patient stroke unit or with t...
Japan Statin Treatment Against Recurrent Stroke (J-STARS)
Although hyperlipidemia is not always the risk factor of stroke, inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A(HMG-CoA) reductase can decrease the incidence of stroke in the patient...
Siblings With Ischemic Stroke Study
The purpose of this study is to find the genes that increase the risk of developing an ischemic stroke using DNA samples collected from concordant (stroke-affected) sibling pairs.
PubMed Articles
An association between migraine and ischemic stroke has been observed for many years but exact mechanisms by which migraine can lead to stroke are currently still under investigation. Migraine is rela...
Advances in stroke care will have the greatest effect on stroke outcome if care is delivered within a regional stroke system designed to improve both efficiency and effectiveness. The ultimate goal of...
Predictors of delayed stroke in patients with cervical artery dissection.
BACKGROUND: Stroke in patients with acute cervical artery dissection may be anticipated by initial transient ischemic or nonischemic symptoms. AIM: Identifying risk factors for delayed stroke upon cer...
Postthrombolysis hemorrhage risk is affected by stroke assessment bias between hemispheres.
Stroke symptoms in right hemispheric stroke tend to be underestimated in clinical assessment scales, resulting in greater infarct volumes in right as compared to left hemispheric strokes despite simil...
Age at stroke: Temporal trends in stroke incidence in a large, biracial population.
We describe temporal trends in stroke incidence stratified by age from our population-based stroke epidemiology study. We hypothesized that stroke incidence in younger adults (age 20-54) increased ove...
