Serum Soluble Suppression of Tumorigenicity-2 Levels Predict Cardiovascular Events in Patients Undergoing Incident Peritoneal Dialysis: A Prospective Cohort Study.

Introduction: Biomarkers are urgently required to identify peritoneal dialysis (PD) patients at risk of cardiovascular (CV) events. This study aimed to investigate the predictive value of soluble suppression of tumorigenicity-2 (sST2) for CV events in patients undergoing incident PD.

Methods: In this prospective cohort study, incident PD patients were enrolled. Blood samples to measure sST2 levels were obtained before PD catheter implantation. The patients underwent a standard peritoneal equilibration test (PET) after initiation of PD for 4-6 weeks. The sST2 levels in both serum and dialysate were determined using enzyme-linked immunosorbent assay. CV events were recorded during the follow-up period.

Results: A total of 137 patients were enrolled. During the follow-up period of 17.3 months, 49 (35.76%) patients experienced CV events. When patients were dichotomized based on the median values and the calculated cutoff values of sST2, the higher sST2 group had 2.980- and 3.048-fold increased risks of CV events, respectively, when compared with the lower sST2 group. Moreover, the prognostic value of sST2 remained significant as a continuous variable (per 1 standard deviation increase, hazard ratio [HR] = 1.037, 95% confidence interval [CI] 1.010-1.066, p = 0.008). N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were found to indicate a higher risk only when dichotomized based on the calculated cutoff values. Furthermore, serum sST2 and NT-proBNP levels simultaneously above the calculated cutoff values were associated with a higher risk of CV events (HR = 3.398, 95% CI 1.813-6.367, p < 0.001).

Conclusion: Baseline serum sST2 level is an independent predictor of the risk of CV events in patients receiving incident PD, and in combination with NT-proBNP level, it can provide a more accurate predictive value.