Cardiac Biomarker BNP Found to Predict Kidney Failure in Diabetic Patients Even at Clinically Normal Levels

Juntendo University study shows BNP blood levels can predict diabetic kidney failure, offering a new way to identify high-risk patients before organ damage.

By: AXL Media

Published: Mar 24, 2026, 9:05 AM EDT

Source: Information for this report was sourced from Juntendo University Research Promotion Center

The Biological Interdependence of the Heart and Kidneys

The medical community has long recognized the "cardiorenal interaction," a physiological link where dysfunction in the heart or kidneys inevitably accelerates deterioration in the other. This interdependence is particularly dangerous for patients with diabetes, who face a heightened vulnerability to both cardiovascular and chronic kidney disease (CKD). As new therapies like SGLT2 inhibitors demonstrate protective effects for both organs, the search for early warning signs has intensified. Researchers at Juntendo University have now identified B-type natriuretic peptide (BNP)—a protein traditionally used to monitor heart failure—as a critical tool for predicting the future of a patient's kidney function.

Expanding the Diagnostic Role of Cardiac Wall Stress Markers

BNP is typically released by the heart in response to changes in pressure and wall stress, serving as a gold-standard biomarker for cardiac health. However, Associate Professor Maki Murakoshi and her team sought to determine if this "cardiac" marker could provide early insight into renal impairment. While urinary biomarkers like the albumin-to-creatinine ratio (UACR) are the standard for assessing kidney damage, they do not always capture the full picture of cardiorenal vulnerability. The Juntendo study, published in Diabetes Research and Clinical Practice, suggests that BNP levels can signal impending kidney decline even when those levels fall within what is currently considered the "normal" clinical range.

Longitudinal Evidence of Kidney Function Deterioration

The study followed 636 adults with diabetes over a median period of 5.4 years, monitoring their estimated glomerular filtration rate (eGFR) for signs of significant decline. The researchers defined a successful prediction as identifying an eGFR drop of at least 30%, a benchmark for serious kidney deterioration. The findings were striking: BNP demonstrated a prognostic performance comparable to established urinary markers like UACR and dipstick proteinuria. Even after adjusting for age, sex, and existing clinical variables, elevated BNP remained an independent and reliable predictor of which patients would experience a rapid loss of kidney function.