Blood biomarker studies focus on stroke and TBI

Woodruff Health Sciences Center | Feb. 22, 2012

Contact

Juliette Merchant
404-778-1503
jmmerch@emory.edu

Researchers at Emory University School of Medicine, led by Michael Frankel, MD, Emory professor of neurology and director of Grady Hospital's Marcus Stroke & Neuroscience Center, are studying biomarkers as part of two ancillary studies of blood samples using two grants from the National Institutes of Health.
Our blood may serve as a predictive window for stroke and accurately tell doctors what is happening in the brain of patients with acute traumatic brain injury (TBI). Researchers at Emory University School of Medicine believe biomarkers circulating in the bloodstream could hold the key to identifying which patients are at risk for recurrent stroke as well as a precise diagnostic tool for assessing the severity of TBI.

Lead by principal investigator Michael Frankel, MD, professor of neurology at Emory School of Medicine and Director of Grady Hospital’s Marcus Stroke & Neuroscience Center, the Emory research team is studying biomarkers as part of an ancillary study of blood samples with two grants from the National Institutes of Health.

In the $1.47 million, four-year grant called “Biomarkers of Ischemic Outcomes in Intracranial Stenosis” (BIOSIS), Emory researchers are analyzing blood samples from 451 patients from around the country enrolled in a study known as SAMMPRIS (Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis), the first randomized, multicenter clinical trial designed to test whether stenting intracranial arteries would prevent recurrent stroke.

“The goal is to learn more about stroke by studying proteins and cells in the blood that reflect the severity of disease in arteries that leads to stroke. If we can test blood samples for proteins and cells that put patients at high risk for stroke, we can better tailor treatment for those patients,” says Frankel, who has a proven track record of successful funding in this innovative field of research.

Patients with narrowed brain arteries, known as intracranial stenosis, have a particularly high-risk of disease leading to stroke. Stroke is the third leading cause of death in the U.S. and a leading cause of adult disability. Approximately 795,000 Americans experience a stroke each year and about 185,000 of those strokes are recurrent strokes. At least 1 in 4 (25 to 35 percent) of the 795,000 Americans who have a stroke each year will have another stroke within their lifetime. Within five years of a first stroke, the risk for another stroke can increase more than 40 percent. Recurrent strokes often have a higher rate of death and disability because parts of the brain already injured by the original stroke may not be as resilient. BIOSIS uses blood samples to predict risk of a stroke occurring in the future.

“Biomarkers of Injury and Outcome in ProTECT III” (BIO-ProTECT) is a $2.6 million, five-year NIH-funded grant in which Frankel’s team is using blood to determine what is happening in the brain of patients with acute TBI. The blood samples are from patients enrolled in the multicenter clinical trial ProTECT III (Progesterone for Traumatic brain injury, Experimental Clinical Treatment), a study led by Emory Emergency Medicine Professor David Wright, MD, which is assessing the use of progesterone to treat TBI in 1,140 patients at 17 centers nationwide.

TBI is the leading cause of death and disability among young adults in the US and worldwide. According to the Centers for Disease Control and Prevention, approximately 1.4 million Americans sustain a traumatic brain injury each year, leading to 275,000 hospitalizations, 80,000 disabilities, and 52,000 deaths.
Acute TBI leads to a cascade of cellular events set in motion by the initial injury that ultimately lead to cerebral edema (swelling of the brain), cellular disruption and sometimes death. Tissue breakdown leads to the release of proteins into the bloodstream. These proteins may serve as useful biomarkers of the severity of the injury and perhaps provide useful information about response to treatment.

Using the large patient group in the ProTECT III trial, the researchers hope to validate promising TBI biomarkers as predictors of clinical outcome and also evaluate the relationship between progesterone treatment, biomarker levels and outcome. “If we can better determine the amount of brain injury with blood samples, we can use blood to help doctors better assess prognosis for recovery, and, hopefully whether a patient will respond to treatment with progesterone,” says Frankel.