Kidney function does not influence variation in biomarkers of acute heart disease

In individuals with hypertension and increased CVD risk but no CVD, annual variations of NT-proBNP and hs-cTnT levels were not influenced by eGFR.

This summary is based on the publication of Bansal N, Katz R, Seliger S, et al. - Variation of NT-proBNP and High-Sensitivity Cardiac Troponin T Across Levels of Estimated Glomerular Filtration Rate: The SPRINT Trial. Circulation. 2024 Mar 19;149(12):967-969. doi: 10.1161/CIRCULATIONAHA.123.066377

Introduction and methods

Background

For patients with CKD, thresholds to interpret biomarkers of acute heart disease are lacking. To overcome this issue, baseline levels of NT-proBNP and hs-cTnT could be established for each individual patient and then used for comparison when they have symptoms suggestive of acute HF or acute MI. As this strategy requires stable values in the absence of acute disease, information on the variation of these biomarkers over time is needed.

Aim of the study

The authors assessed the annual variation of NT-proBNP and hs-cTnT levels across several eGFR categories.

Methods

This was a post-hoc analysis of the SPRINT (Systolic Blood Pressure Intervention Trial) study, which was designed to determine the most appropriate systolic blood pressure targets to reduce CV morbidity and mortality in individuals with no diabetes [1]. In this open-label RCT conducted in the US, 9361 individuals with hypertension (systolic blood pressure ≥130 mmHg) and increased CVD risk but no diabetes were randomized to intensive blood pressure–lowering treatment or standard treatment. In the current analysis, 4615 individuals with baseline and ≥1 follow-up measurements of NT-proBNP and hs-cTnT, baseline eGFR measurement (≥20 mL/min/1.73 m²), no prevalent CVD at baseline or within 3 years, and no annual eGFR decline >3 mL/min/1.73 m² were included.

Main results

NT-proBNP

• The median annual change in NT-proBNP was 0% (IQR: –24.1% to 26.4%) in individuals with eGFR ≥60 mL/min/1.73 m² (n=3541), 5.27% (IQR: –20.0% to 30.0%) in those with eGFR 45–59 mL/min/1.73 m² (n=703), and 3.16% (–16.6% to 28.6%) in those with eGFR <45 mL/min/1.73 m² (n=371).
• The annual percent change in NT-proBNP for eGFR <45 mL/min/1.73 m² compared with ≥60 mL/min/1.73 m² was 3.70 (IQR: –2.47 to 9.88).
• The coefficients of variation within individuals were similar across eGFR categories (P=0.1), as were the positive and negative reference change values.

hs-cTnT

• The median annual change in hs-cTnT was 0% (IQR:–5.8% to 4.9%), 0% (IQR:–6.8% to 7.3%), and 0.5% (IQR:–6.9% to 9.3%) in patients with eGFR ≥60, 45–59 and <45 mL/min/1.73 m², respectively.
• The eGFR was also not associated with annual percent change in hs-cTnT (eGFR <45 vs. ≥60 mL/min/1.73 m²: 1.17; IQR: –1.66 to 4.01).
• The within-individual coefficients of variation were similar across eGFR categories (P=0.9), as were the positive and negative reference change values.

Conclusion

Among SPRINT trial participants with hypertension and increased CVD risk but no CVD or diabetes, annual variations of NT-proBNP and hs-cTnT levels were not influenced by eGFR. The authors conclude their “data suggest it may be useful to obtain baseline NT-proBNP and hs-cTnT levels in stable asymptomatic patients with CKD with the purpose of providing a reference for comparison if and when they develop symptoms that may be a result of acute heart failure or acute myocardial infarction.”

Find this article online at Circulation.

Reference

1. Wright JT Jr., Williamson JD, Whelton PK, Snyder JK, Sink KM, Rocco MV, Reboussin DM, Rahman M, Oparil S, Lewis CE, et al; SPRINT Research Group. A randomized trial of intensive versus standard blood-pressure control. N Engl J Med. 2015;373:2103–2116. doi: 10.1056/NEJMoa1511939