Background: Myocardial injury is an important pediatric diagnosis. Establishing normative data from a representative pediatric sample is vital to provide accurate upper reference limits (URLs) for defining myocardial injury using high-sensitivity (hs) cardiac troponin. Methods: Among participants aged 1 to 18 years in the 1999-2004 National Health and Nutrition Examination Survey, we measured hs-troponin-T using one assay (Roche) and hs-troponin-I using three assays (Abbott, Siemens, and Ortho). In a strictly defined healthy subgroup, we estimated 97.5^{th} and 99^{th} percentile URLs for each assay using the recommended non-parametric method. Results: Of 5,695 pediatric participants, 4,029 met criteria for the healthy subgroup (50% male, mean age 12.6 years). Our 99^{th} percentile URL estimates for all four hs-troponin assays among children and adolescents were lower than the manufacturer-reported URLs (derived from adults). The 99^{th} percentile URLs (95% confidence interval, CI) were : 15 ng/L (95% CI 12, 17) for hs-troponin T, 16 ng/L (95% CI 12, 19) for hs-troponin I Abbott, 38 ng/L (95% CI 25, 46) for hs-troponin I Siemens, and 7 ng/L (95% CI 5, 12) for hs-troponin I Ortho. The 95% CIs for age-, sex- and race-specific 99^{th} percentile URLs overlapped. However, the 97.5^{th} percentile URL for each assay was measured with superior statistical precision (i.e., tighter 95% CIs) and demonstrated differences by sex. For male vs female children, 97.5^{th} URLs were 11 ng/L (95% CI 10, 12) vs. 6 ng/L (95% CI 6, 7) for hs-troponin T, 9 ng/L (95% CI 7, 10) vs. 5 ng/L (95% CI 4, 6) for hs-troponin I Abbott, 21 ng/L (95% CI 18, 25) vs. 11 ng/L (95% CI 9, 13) for hs-troponin I Siemens, and 4 ng/L (95% CI 3, 5) vs. 2 ng/L (95% CI 1, 3) for hs-troponin I Ortho. In contrast to the 99^{th} percentiles, the point estimates of 97.5^{th} percentile pediatric URLs for cardiac troponin were also much more stable to differences in the analytic approaches taken to estimate URLs. Conclusions: Because myocardial infarction is rare in youth, the use of statistically more precise and reliable sex-specific 97.5^{th} percentile URLs might be considered to define pediatric myocardial injury.
【저자키워드】 pediatric, Sex, myocardial injury, Child, Adolescent, upper reference limit, high-sensitivity troponin,