Age- and sex-specific upper reference limits for cardiac biomarkers in Chinese children and adolescents: a prospective study

Cardiac biomarkers are being increasingly applied in pediatric populations, including those with cardiogenic and non-cardiogenic myocardial injury disease. The upper reference limits of biomarkers are an important reference for disease diagnosis and health evaluation. However, the upper reference limits of pediatric cardiac biomarkers remains unknown. A total of 1,797 serum samples were collected prospectively from healthy respondents aged 0 to 18 years old. These samples were analyzed using Roche cobas e411 to determine the concentrations of hs-cTnT, CK-MB mass, and NT-proBNP. The upper reference limits and 90% confidence interval were calculated according to Clinical and Laboratory Standards Institute C28- A3 guidelines. The study successfully established the upper reference limits for hs-cTnT, CK-MB mass, and NT-proBNP in healthy children and adolescents aged 0 to 18. The hs-cTnT, CK-MB mass, and NT-proBNP levels were visibly higher in neonatal serum. With the increase in age, hs-cTnT, CK-MB mass, and NT-proBNP decline gradually. They decrease quickly in the first year after birth and decrease slowly after 1 year old. Gender differences were observed in the concentrations of hs-cTnT and CK-MB mass among healthy children and teenagers aged 10 to 18 and 13 to 18. Specifically, boys had relatively higher concentrations of hs-cTnT and CK-MB mass. However, no gender difference was found in NT-proBNP concentration. The concentrations of hs-cTnT, CK-MB mass, and NT-proBNP were simultaneously tested in healthy Chinese children for the first time. The specific upper reference limits of age and gender in pediatrics were established. The results provide comprehensive references for medical institutions specializing in children's healthcare, which are conducive to preliminary screening, diagnosis, and treatment of pediatric cardiovascular diseases.