Reference interval and the role of soluble suppression of tumorigenicity 2 (sST2) in subclinical cardiac dysfunction at health checkups

Background Soluble ST2 (sST2) is known to predict adverse outcomes and death in individuals with established heart failure. However, the role of sST2 testing in the general population has not been established. The aims of this study were to determine the reference interval (RI) and the clinical utility of sST2 in subclinical cardiac dysfunction in general population. Methods This cross‐sectional study consecutively selected 41,806 general subjects at health checkups who underwent echocardiography and sST2 testing at 16 health promotion centers in 13 Korean cities. The reference subjects were obtained among those with normal findings in echocardiography. Sex‐specific RIs were established according to the CLSI C28‐A3 guidelines. sST2 was measured using immunoassay with the Presage ST2 assay (Critical Diagnostics). Results In the general subjects, age, sex, BMI, systolic blood pressure, blood glucose, creatinine, liver function, and triglycerides were associated with the sST2 levels. The RI for sST2 was higher in males (≤49.6 ng/mL, 95% CI = 48.5‐51.5) than in females (≤44.5 ng/mL, 95% CI = 43.5‐45.6) and higher in subjects aged < 40 years than ≥ 40 years in both sexes. The sST2 levels were 29.1 ± 10.7 (mean ± SD) and 29.1 ± 14.4 ng/mL in the groups with normal cardiac function and subclinical cardiac dysfunction, respectively. The sST2 level was not associated with subclinical cardiac dysfunction (odd ratio = 1.002, P  = .13). Conclusions RIs obtained from a large and echocardiography‐proven healthy community‐based sample are presented. Subclinical cardiac dysfunction was associated with older age, male sex, and metabolic factors but not with the sST2 level.