Biological Variation of Cardiac Troponins in Chronic Kidney Disease

Jones, Rebecca; Barrett, Jonathan; Brettell, Elizabeth; Cockwell, Paul; Dalton, R Neil; Deeks, Jon; Eaglestone, Gillian; Pellatt-Higgins, Tracy; Kalra, Philip A; Khunti, Kamlesh; Morris, Frances; Ottridge, Ryan; Sitch, Alice; Stevens, Paul E; Sharpe, Claire; Sutton, Andrew; Taal, Maarten; Lamb, Edmund J

Abstract

Background
Patients with chronic kidney disease often have increased plasma cardiac troponin concentration in the absence of myocardial infarction. Incidence of myocardial infarction is high in this population, and diagnosis, particularly of non ST-segment elevation myocardial infarction (NSTEMI), is challenging. Knowledge of biological variation aids understanding of serial cardiac troponin measurements and could improve interpretation in clinical practice. The National Academy of Clinical Biochemistry (NACB) recommended the use of a 20% reference change value in patients with kidney failure. The aim of this study was to calculate the biological variation of cardiac troponin I and cardiac troponin T in patients with moderate chronic kidney disease (glomerular filtration rate [GFR] 30–59 mL/min/1.73 m2).

Methods and results
Plasma samples were obtained from 20 patients (median GFR 43.0 mL/min/1.73 m2) once a week for four consecutive weeks. Cardiac troponin I (Abbott ARCHITECT® i2000SR, median 4.3 ng/L, upper 99th percentile of reference population 26.2 ng/L) and cardiac troponin T (Roche Cobas® e601, median 11.8 ng/L, upper 99th percentile of reference population 14 ng/L) were measured in duplicate using high-sensitivity assays. After outlier removal and log transformation, 18 patients’ data were subject to ANOVA, and within-subject (CVI), between-subject (CVG) and analytical (CVA) variation calculated. Variation for cardiac troponin I was 15.0%, 105.6%, 8.3%, respectively, and for cardiac troponin T 7.4%, 78.4%, 3.1%, respectively. Reference change values for increasing and decreasing troponin concentrations were +60%/–38% for cardiac troponin I and +25%/–20% for cardiac troponin T.

Conclusions
The observed reference change value for cardiac troponin T is broadly compatible with the NACB recommendation, but for cardiac troponin I, larger changes are required to define significant change. The incorporation of separate RCVs for cardiac troponin I and cardiac troponin T, and separate RCVs for rising and falling concentrations of cardiac troponin, should be considered when developing guidance for interpretation of sequential cardiac troponin measurements.

Citation

Jones, R., Barrett, J., Brettell, E., Cockwell, P., Dalton, R. N., Deeks, J., Eaglestone, G., Pellatt-Higgins, T., Kalra, P. A., Khunti, K., Morris, F., Ottridge, R., Sitch, A., Stevens, P. E., Sharpe, C., Sutton, A., Taal, M., & Lamb, E. J. (2020). Biological Variation of Cardiac Troponins in Chronic Kidney Disease. Annals of Clinical Biochemistry, 57(2), 162-169. https://doi.org/10.1177/0004563220906431

• Journal Article Type: Article
• Acceptance Date: Feb 21, 2020
• Online Publication Date: Feb 5, 2020
• Publication Date: 2020-03
• Deposit Date: Feb 27, 2020
• Publicly Available Date: Mar 2, 2020
• Journal: Annals of Clinical Biochemistry: International Journal of Laboratory Medicine
• Print ISSN: 0004-5632
• Electronic ISSN: 1758-1001
• Publisher: SAGE Publications
• Peer Reviewed: Peer Reviewed
• Volume: 57
• Issue: 2
• Pages: 162-169
• DOI: https://doi.org/10.1177/0004563220906431
• Keywords: Clinical Biochemistry; General Medicine
• Public URL: https://nottingham-repository.worktribe.com/output/4045334
• Publisher URL: https://journals.sagepub.com/doi/10.1177/0004563220906431