Determination of 19 Cardiac Troponin I and T Assay 99th Percentile Values from a Common Presumably Healthy Population

• Published in: Clinical chemistry (Baltimore, Md.) Vol. 58; no. 11; pp. 1574 - 1581
• Main Authors: Apple, Fred S, Ler, Ranka, Murakami, MaryAnn M
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for Clinical Chemistry 01.11.2012; Oxford University Press
• Subjects: Adult; Analytical, structural and metabolic biochemistry; Architects; Biological and medical sciences; Cardiology; Diabetes; Female; Fundamental and applied biological sciences. Psychology; Heart attacks; Humans; Immunoassay; Instrumentation; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Molecular biophysics; Point-of-Care Systems; Reference Values; Sensitivity and Specificity; Sex Factors; Shipments; Troponin I - blood; Troponin T - blood; Young Adult; Heart; Assay; Healthy subject; Troponin I; Clinical biology; Biochemistry; Circulatory system; Molecular biology; Troponin T
• ISSN: 0009-9147; 1530-8561; 1530-8561
• DOI: 10.1373/clinchem.2012.192716

Between-assay comparability of 99th percentiles for cardiac troponin concentrations has not been assessed systematically in a single population for a large number of assays. We determined 99th percentiles for 19 cardiac troponin assays in heparin plasma samples from a population of 272 and 252 presumably healthy males and females, respectively. The assays evaluated included 1 cardiac troponin T (cTnT) assay from Roche and 18 cTnI assays from Abbott, Alere, Beckman, bioMerieux, Instrumentation Laboratory, Ortho-Clinical Diagnostics, Singulex, Siemens, and Roche. Five of these assays were categorized as high-sensitivity, 9 as sensitive-contemporary, and 5 as point-of-care (POC) assays. For high-sensitivity cTnI (hs-cTnI) assays 99th percentiles varied from 23 to 58 ng/L. At least 80% of individuals had measurable hs-cTnI, whereas only 25% had measurable high-sensitivity cTnT. All high-sensitivity cardic troponin assays had 99th percentiles that were 1.2-2.4-fold higher in males than females. For the 9 sensitive-contemporary cTnI assays, 99th percentiles varied from 12 to 392 ng/L, and only the Beckman assay gave measurable concentrations in a substantial portion of the population (35% vs ≤6% for the others). Seven of these 9 assays had 1.3-5.0-fold higher 99th percentiles for males than females. For 5 cTnI POC assays, 99th percentiles varied from <10 to 40 ng/L. The Instrumentation Laboratory assay gave measurable results in 27.8% of study participants vs ≤6% for the others. Correlations were generally poor among assays. Among cardiac troponin assays 99th percentile concentrations appear to differ. High-sensitivity assays provide measurable cardiac troponin results in a substantially greater fraction of presumably healthy individuals.