Elevated ST2 Biomarker Levels Strongly Indicate Heart Failure and Mortality in HIV Patients
13 Nov 2012Critical Diagnostics, makers of the Presage® ST2 Assay, announced that during a presentation at the American Heart Association Scientific Sessions in Los Angeles, the results of a study demonstrated that elevated levels of the biomarker ST2 in HIV patients was strongly indicative of the development of heart failure and mortality.
The Joint United Nations Program UNAIDS estimates that there are now 33 million people living with HIV/AIDS worldwide. The Center for Disease Control estimates that more than one million people in the U.S. are living with HIV. AIDS ranks with malaria and tuberculosis as one of the top three deadliest infectious diseases among adults, and is the fourth leading cause of death worldwide.
This comprehensive, 8-year retrospective study conducted by researchers at University of California and Massachusetts General Hospital, entitled, ST2 and NT-proBNP Are Associated with Cardiac Dysfunction and Mortality in HIV-Infected Individuals, recruited 332 HIV-infected patients and 50 control subjects asymptomatic for heart failure.
The study concluded that patients with ST2 levels above a specific cut-point had a 40% greater risk of developing diastolic dysfunction. Diastolic dysfunction or diastolic heart failure, which often produces no advanced symptoms at all, refers to decline in performance of one or both ventricles of the heart, where they become stiff, and as a result, cannot fill completely and blood can pool in the body's organs, mainly the lungs.
Furthermore, study results showed that elevated ST2 levels in these HIV-infected patients were modestly associated with risk for systolic dysfunction. Systolic dysfunction is the difficulty of the left ventricle to empty or eject the blood from its chamber and defined in terms of left ventricular ejection.
The natriuretic peptide NT-proBNP was included in the study, but researchers found that while levels were significantly elevated in HIV-infected patients, high concentrations of NT-proBNP were not associated with development of either diastolic or systolic dysfunction. The study did, however, find that a combined elevation of ST2 and NT-proBNP were predictive of death in this patient population.
"Patients with chronic syndromes are known to be at an increased risk for developing heart failure. Unfortunately, identification of which patients are likely to develop diastolic dysfunction is particularly difficult," notes Critical Diagnostics' President James Snider. "This study shows that ST2 uniquely predicts which patients with chronic HIV infection are progressing down this path and thus may allow the physician to personalize their treatment."
"Particularly noteworthy is that ST2 remains not only powerfully prognostic for outcomes in patients with heart failure but this study and similar studies in community cohorts also illustrates the power of ST2 to identify patients who are developing heart failure," says David Geliebter, CEO of Critical Diagnostics. "This fits perfectly with our goal of helping physicians realize the vision of patient centric medicine."