OBJECTIVEThis study was designed to investigate the plasma level of soluble ST2 (sST2) and related influencing factors, and establish its reference value in the healthy community-based population in Beijing area of China.

METHODSWe measured plasma sST2 level by enzyme-linked immunosorbent assay between March 2012 and August 2012 in 1 334 healthy subjects in communities, including 597 males and 737 females. Empiric and quantile regression methods were used to determine the reference range of plasma sST2. A multiple linear regression model was established to analyze the factors that might affect the level of plasma sST2.

RESULTSGender is the most important factor affecting the plasma level of sST2 in healthy people. Plasma level of sST2 is significantly higher in men than in women (P < 0.01). Within each age strata, i.e. < 45, 45-54, 55-64, ≥ 65 years old, the plasma levels of sST2 were significantly higher in men than age-matched female (all P < 0.01). Age, body mass index (BMI), systolic blood pressure, diastolic blood pressure, and smoking did not affect plasma sST2 level. Reference range of sST2 was 5.7-53.5 µg/L for men and 4.4-42.4 µg/L for women (95% nonparametric reference interval). The one-side upper 95th percentile value of sST2 to discriminate the cardiovascular disease from healthy state was 47.2 µg/L for men and 37.2 µg/L for women.

CONCLUSIONSThis study established the normal reference range of plasma sST2 in healthy community-based population. The major influencing factor of sST2 level in healthy population is gender.