Patient medians for NT-proBNP from six Swedish counties 2011-2021
Morgan Lundgren1, Peter Ridefelt1, Maria K Eriksson2,3
1Department of Medical Sciences, Clinical Chemistry, Uppsala University, Uppsala, Sweden.
Summary
Patient medians for N-terminal pro-B-type natriuretic peptide (NT-proBNP) testing reflect manufacturer differences found in quality assessments. These patient data offer a valuable tool for monitoring assay performance and ensuring diagnostic accuracy.
Area of Science:
- Clinical Chemistry
- Biomarker Analysis
- Quality Assurance in Diagnostics
Background:
- N-terminal pro-B-type natriuretic peptide (NT-proBNP) is vital for heart failure diagnosis and management.
- External quality assessment (EQA) schemes highlight significant method variations among NT-proBNP manufacturers.
- Patient result medians can potentially serve as indicators of analytical performance and method comparability.
Purpose of the Study:
- To investigate whether inter-manufacturer differences observed in EQA data are also apparent in patient median values.
- To assess the utility of patient medians as a quality indicator for NT-proBNP testing methods.
Main Methods:
- Analysis of over one million NT-proBNP results from adult patients across six Swedish counties between 2011 and 2021.
- Grouping of results by manufacturer method, geographical county, and clinical factors including estimated glomerular filtration rate (eGFR) and diabetes status.
- Calculation of median values and comparison against consensus values.
Main Results:
- Roche assays dominated the market until 2017; subsequent market entry by other manufacturers led to more diverse results.
- Roche and Siemens median results generally aligned with EQA findings, whereas Abbott results showed discrepancies.
- Between 2019-2021, manufacturer results varied from consensus: Roche (+2%), Siemens (+16%), Ortho (-8%), and Abbott (-11%).
- Increased NT-proBNP testing volume correlated with decreased median values, potentially due to guideline updates.
- Patients with reduced eGFR or diabetes exhibited 2-3 times higher NT-proBNP medians, validating the overall median calculations.
Conclusions:
- Patient medians largely confirm inter-manufacturer variations in NT-proBNP testing, consistent with EQA data, with Abbott as a notable exception.
- The observed higher medians in patients with compromised renal function or diabetes support the clinical relevance of patient median data.
- Patient medians represent a clinically meaningful quality indicator, complementing internal and external quality controls for NT-proBNP assay monitoring.
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