Soluble suppression of tumorigenicity 2 (sST2) is a novel biomarker for heart failure (HF). It is known that the prevalence of HF increases with age. This study aimed to determine the reference intervals (RIs) of sST2 in South Koreans aged 60 years and above. From November 2018 to March 2019, serum sST2 levels were measured with the Presage ST2 enzyme-linked immunosorbent assay (Critical Diagnostics, USA) in 153 study participants (99 men and 54 women) with a mean age of 73.4±7.8 years. The median sST2 level was 32.9 ng/mL (interquartile range [IQR], 25.1–39.7 ng/mL) for men and 26.9 ng/mL (IQR, 23.5–34.4 ng/mL) for women. sST2 levels were higher in males than in females (P=0.0117). The central 95% RIs were 10.5–54.7 ng/mL for men and 9.1–46.7 ng/mL for women. The 97.5 percentile upper reference limits were higher in both sexes compared with those of the manufacturer and previous studies. The proportion of the study participants exceeding the cut-off of 35 ng/mL for HF was 33.1% (37 men and 10 women). One must exercise caution when interpreting the sST2 results in the elderly.

Keywords: Soluble suppression of tumorigenicity 2, Heart failure, Reference values, Aged