The prognostic value of sST2 in connective tissue disease patients with pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a severe complication of CTD, being one of the leading causes of mortality for patients with this condition. Soluble suppression of tumorigenicity 2 (sST2) is a novel biomarker associated with adverse clinical outcomes in cardiovascular patients. In this study, we investigated the role of sST2 as a predictor of poor clinical outcome in patients with CTD associated with pulmonary hypertension (CTD-PH).

This retrospective cohort study enrolled 71 CTD-PH patients diagnosed by echocardiography. Twenty-one CTD patients without PH were selected for a control group. A receiver operating characteristic (ROC) curve assessed the predictive value of sST2 in assessing 3-year clinical worsening. Hazard ratios associated with potential predictors of clinical worsening were estimated using Cox proportional hazard models. The primary end point was clinical worsening.

The level of sST2 was significantly elevated in CTD-PH patients compared with the control group. After a mean follow-up of 25.29 (1.88) months, end point events occurred in 26 patients. sST2 was an independent predictor of clinical worsening and all-cause death in patients with CTD-PH. sST2 ≥ 39.99 ng/ml discriminated 3-year clinical worsening with a sensitivity and specificity of 100% and 84.9%, respectively. The patients with both higher levels of sST2 (≥39.99 ng/ml) and N-terminal pro-brain natriuretic peptide (NT-proBNP) (≥300 ng/l) had the worst prognosis.

sST2 ≥ 39.99 ng/ml predicts higher incidence of clinical worsening events in CTD-PH patients. Furthermore, patients with elevated sST2 had significantly worse prognosis among those with high NT-proBNP.