sST2 is a member of the interleukin-1 receptor family known to predict outcome in cardiovascular disease and ischemic stroke. Its role in ICH has not been reported.

To determine if soluble ST2 (sST2) is associated with injury severity and functional outcome after intracerebral hemorrhage (ICH).

sST2 concentration was measured on plasma samples from prospectively collected cohorts totaling 69 patients who presented with ICH to Brigham and Women’s or Yale New Haven Hospitals. Blood samples were drawn at 24 ±12 hours after symptom onset. sST2 was measured using a commercially-available ELISA (Critical Diagnostics, San Diego, CA). Injury severity was determined by the admission Glasgow Coma Scale (GCS), with GCS ≤ 8 defined as severe injury. Outcome was assessed by modified Rankin Scale (mRS) at 90 days, with poor outcome defined as mRS 4-6. The association between sST2 and outcome was determined using logistic regression and receiver operating curve (ROC) analysis.

Patients with a more severe presentation (GCS ≤ 8) had a higher sST2 concentration (173.6ng/ml [IQR 91.1-259.1] vs. 41.5ng/ml IQR [25.4-94.2], p<0.0001). Higher sST2 was associated with poor outcome (OR 0.36, 95% CI 0.20-0.67, p = 0.001). ROC analysis demonstrated that sST2  >111.7ng/mL predicted poor outcome with a sensitivity of 58%, specificity of 81%, and area under the curve of 0.736.  Other predictors of outcome included GCS, hematoma volume, and ICH score. sST2 remained an independent predictor of mRS after adjustment for hematoma volume (adjusted OR 0.40, 95% CI 0.22-0.76, p = 0.005). sST2 was not independent of GCS or ICH score. 

Plasma sST2 is associated with initial GCS and functional outcome after intraparenchymal hemorrhage. These results support the role of sST2 as a candidate biomarker for hemorrhagic stroke and argue for further investigation of the ST2 pathway in the pathogenesis of neurologic injury.