Point-of-care NT-proBNP testing showed excellent agreement with laboratory results in PAH patients (ICC = 0.97), and mailed blood samples remained stable, supporting both rapid clinic-based and remote monitoring approaches.
ICC = 0.97Point-of-care NT-proBNP testing showed near-perfect agreement with laboratory results, supporting its use for immediate clinical decision-making in PAH.
What the researchers found
NT-proBNP point-of-care testing showed excellent agreement with laboratory standards:
- Passing-Bablok analysis: slope = 1.08 (CI 0.97–1.19), intercept = 18.22 (CI -41.6 to 4.5) — indicating equivalent results
- Intraclass correlation coefficient (ICC) = 0.97
- POCT correctly classified 92% of cases against COMPERA 2.0 4-risk-strata thresholds
BNP point-of-care testing was less reliable:
- Passing-Bablok showed non-equivalence (slope = 1.24, CI 1.11–1.31)
- POCT correctly classified only 86% of cases
- BNP identified fewer high-risk patients than NT-proBNP
- BNP and NT-proBNP risk status agreed at only 57% of visits (p < 0.0009)
NT-proBNP in posted (mailed) blood samples showed good agreement with immediately processed samples. Exercise did not have a clinically significant effect on either NT-proBNP or BNP results.
Why it matters
PAH is a serious condition where timely monitoring can be life-saving. Currently, patients must wait for lab results that aren't available during their clinic visit, potentially delaying treatment decisions. Point-of-care testing could enable immediate clinical action, while remote monitoring via mailed samples could reduce the need for frequent hospital visits — particularly important for patients who travel long distances to specialist centers.
How the study worked
This was a prospective study enrolling 41 Group 1 PAH patients across 56 study visits. Blood samples were taken at two time points for both laboratory and point-of-care NT-proBNP and BNP testing. Separate samples were mailed back to the laboratory to test stability during postal transit, simulating remote monitoring. Some samples were assessed before and after exercise. Agreement between methods was evaluated using Passing-Bablok regression, ICC, and COMPERA 2.0 risk stratification thresholds.
What this study cannot tell us
The study enrolled only 41 patients, though this met the pre-specified sample size calculation. It was conducted at a single center. The POCT device used is specific and results may vary with different devices. The postal stability testing simulated remote monitoring but actual home-based sample collection introduces additional variables. The study focused on Group 1 PAH and may not generalize to other forms of pulmonary hypertension.
How to read the evidence
This is a prospective diagnostic accuracy study with pre-specified sample size calculations and rigorous statistical methods. While relatively small, it met its power requirements and provides strong evidence for the reliability of NT-proBNP POCT in PAH.
When this study was published
Published in 2025 and registered on ClinicalTrials.gov (NCT05421949), this study reflects current interest in decentralizing PAH monitoring through point-of-care and remote testing technologies.
The bigger picture
NT-proBNP and BNP are natriuretic peptides released by the heart under stress and are among the most widely used cardiac biomarkers. This study is part of a broader movement toward point-of-care and remote monitoring in cardiopulmonary diseases, enabled by advancing POCT technology. The finding that BNP and NT-proBNP often disagree on risk classification has important implications for standardizing PAH monitoring guidelines.
Questions still open
- Should PAH monitoring guidelines standardize on NT-proBNP rather than BNP given the poor agreement between the two biomarkers?
- Could remote NT-proBNP monitoring via mailed samples reduce hospital visits and healthcare costs for PAH patients?
- How would integrating point-of-care NT-proBNP into clinical workflows change treatment decision-making at the point of care?
Common questions
What is NT-proBNP and why is it important in PAH?
Are BNP and NT-proBNP interchangeable?
Read the original research
NT-proBNP and BNP Testing in Pulmonary Arterial Hypertension: Point-of-Care and Remote Monitoring.
Respirology (Carlton, Vic.), 30(11), 1094-1103
Citation
Durrington, Charlotte; Battersby, Christian; Holt, Laura; Fairman, Alexandra; Strickland, Scarlett; Salisbury, Thomas; Turton, Helena A; Watson, Lisa; Smith, Ian; Roman, Stefan; Ablott, Jenna; Hitchcock, Felicity; Roddis, Chloe; Oakes, Eleanor; Wilshaw, Heather; Woodrow, Iain; Armstrong, Iain; Charalampopoulos, Athanasios; Elliot, Charlie A; Hameed, Abdul; Hamilton, Neil; Hurdman, Judith A; Lawrie, Allan; Middleton, Jennifer T; Zafar, Hamza; Rothman, Alex M K; Condliffe, Robin; Lewis, Robert A; Kiely, David G; Thompson, A A Roger. (2025). NT-proBNP and BNP Testing in Pulmonary Arterial Hypertension: Point-of-Care and Remote Monitoring.. Respirology (Carlton, Vic.), 30(11), 1094-1103. https://doi.org/10.1111/resp.70087