Abstract P118: Plasma Levels of Interleukin Receptor Soluble ST2 Predict Disease Severity and Mortality in Patients With Acute Respiratory Distress Syndrome (ARDS)
Background: ST2 is a novel biomarker that is induced under conditions of both inflammation and myocardial strain. We investigated the association of soluble ST2 (sST2) concentrations with organ failure and mortality in subjects with Acute Respiratory Distress Syndrome (ARDS).
Methods: We conducted a single center prospective study from ICUs at Massachusetts General Hospital. Patients were diagnosed with ARDS according to American-European Consensus Committee criteria. Blood taken within 72 hours of ARDS onset was assayed for sST2. Patients were followed for the outcomes of number of organ failures, number of days free of mechanical ventilation and mortality at 60 days.
Results: 128 patients were enrolled, 53 of whom died (41%). The overall median sST2 concentration was 556.8 ng/mL [IQR 236.8 –1786.2 ng/mL]. sST2 levels were higher among non-survivors (1036.3 vs. 437.3 ng/mL, P=.003). Patients with sST2 levels above the median had significantly greater organ failure (P<.0001) and significantly fewer days free of mechanical ventilation (P=.01). sST2 level was strongly correlated with APACHE III score (R=.47, P<.0001), and in age-adjusted Cox proportional hazards analysis, a higher sST2 concentration was associated with 60 day mortality (HRadj=2.30; 95% CI=1.32– 4.02, P=.003). The mortality risk associated with an elevated sST2 was evident early and extended to the entire range of follow up (figure⇓).
Conclusion: Elevated sST2 levels are associated with disease severity and outcomes in ARDS. This suggests a potential pivotal role of this marker in the pathophysiology of ARDS, and a possible role of sST2 for prognostication as well.