Two common biomarkers have now been shown to improve the ability to predict who will suffer from a stroke.
Results from new research conducted at the Methodist DeBakey Heart & Vascular Center in Houston were published in the online version of the journal Stroke .
Stroke is the third leading cause of death in the U.S. and a leading cause of disability. Accurate risk assessment is imperative because stroke is preventable with medical therapy and lifestyle changes.
"If we can identify increased risk for stroke, we can recommend exercise, smoking cessation, and cholesterol and blood pressure medication to reduce a person's risk for stroke by more than 30 percent," said Dr. Vijay Nambi, lead author on the study and cardiologist at the Methodist DeBakey Heart & Vascular Center and Baylor College of Medicine. "Adding these two biomarkers to traditional risk assessment tools improves our ability to do that."
"The study found that adding two biomarkers associated with inflammation, lipoprotein-associated phospholipase A2 (Lp-PLA2) and high-sensitivity C-reactive protein (CRP), to traditional risk factor assessment for stroke changed the risk category in which some patients were placed," said Dr. Christie Ballantyne, director of the Center for Cardiovascular Disease Prevention at the Methodist DeBakey Heart & Vascular Center and Baylor, and senior investigator in the study. "The greatest impact was on patients who, with traditional risk assessment, were placed into the intermediate risk category. With the addition of the biomarkers, Lp-PLA2 and CRP testing, 39 percent of those patients were reclassified into a lower or higher risk group."
Traditional risk factors for stroke include high blood pressure, smoking, high cholesterol, diabetes, obesity and other hereditary factors.
This study was funded by the National Heart, Lung and Blood Institute (NHLBI) and by an unrestricted research grant from GlaxoSmithKline. This was a multi-center study led by investigators at The Methodist Hospital in Houston. Lp-PLA2 was measured using the PLAC test from diaDexus, Inc.
About the study
Data for the current analysis was from the Atherosclerosis Risk in Communities (ARIC) study. The ARIC study is a prospective biracial study of atherosclerotic cardiovascular disease incidence. 15,792 individuals, initially aged 45 to 64 years, were recruited between 1987 and 1989 from four communities in the United States.
In a prospective case cohort (n=949) study in 12,762 apparently healthy, middle-aged men and women in the ARIC study, we first examined whether Lp-PLA2 and hs-CRP levels improved the area under the curve (AUC) of receiver operating characteristic curves for five-year ischemic stroke risk. We then examined how Lp-PLA2 and hs-CRP levels altered classification of individuals into low-, intermediate-, or high-risk categories compared with traditional risk factors.