Januzzi JL Jr et al. (2007) Measurement of the interleukin family member ST2 in patients with acute dyspnea: results from the PRIDE (Pro-Brain Natriuretic Peptide Investigation of Dyspnea in the Emergency Department) study. J Am Coll Cardiol 50: 607–613

Evidence is accumulating to indicate that measurement of levels of the interleukin 1 receptor family member ST2 might have prognostic value in patients with heart failure (HF). In vitro studies have shown marked parallels between the expression profiles of ST2 and those of N-terminal pro-brain natriuretic peptide, and elevated levels of ST2 have been documented in patients with HF in small studies.

By use of data from the PRIDE study, Januzzi et al. examined the prognostic utility of ST2 measurement in a group of 593 dyspneic patients including both those with and those without acute destabilized HF. Median ST2 concentrations were significantly higher in patients with HF than in patients without (0.50 ng/ml vs 0.15 ng/ml; P <0.001), confirming a possible biological link between ST2 and the presence and severity of HF.

After 1 year of follow-up, 93 patients had died. Median ST2 concentrations were significantly higher among decedents than among survivors (1.03 ng/ml vs 0.18 ng/ml; P <0.001), and an ST2 concentration of ≥0.20 ng/ml dramatically increased the risk of death at 1 year when the population was considered as a whole (hazard ratio 5.6, 95% CI 2.2–14.2), and especially in individuals with HF (hazard ratio 9.3, 95% CI 1.3–17.8). Further analyses showed that models incorporating both ST2 and N-terminal pro-brain natriuretic peptide were uniquely able to identify those patients at the highest risk of death. The authors conclude that ST2 is a novel biomarker in HF, and that it is strongly predictive of mortality at 1 year among patients with dyspnea, suggesting that ST2 testing might enable enhanced risk stratification of dyspneic patients.