MicroRNAs in Blood Predict Kidney & Heart Risk in Chronic Kidney Disease

Researchers have identified a promising new way to assess cardiovascular risk in patients with chronic kidney disease (CKD) – analyzing tiny RNA molecules carried within the bloodstream. A study from the Institute of Science Tokyo, published in the Journal of the American Heart Association, demonstrates that these molecules, known as microRNAs, can accurately predict both the decline of kidney function and the likelihood of future cardiovascular events. This minimally invasive approach offers a potential improvement over current methods, which often rely on indicators of existing damage rather than predicting future risk.

Chronic kidney disease affects over 850 million people worldwide and is increasingly recognized as a global public health threat. Even as kidney failure is a serious consequence, a significant proportion of CKD patients die from cardiovascular complications – heart attacks, strokes and heart failure – before ever needing dialysis or a kidney transplant. Managing this risk is complicated by the unpredictable nature of CKD progression. doctors often struggle to identify those most likely to experience rapid decline or cardiovascular events.

Beyond Traditional Biomarkers

Current methods for monitoring CKD often focus on measuring protein levels in urine (proteinuria) or assessing glomerular filtration rate, which measures how well the kidneys are filtering waste. While valuable, these measurements reflect existing kidney damage and may not capture the subtle molecular changes that link kidney dysfunction to cardiovascular problems. The need for biomarkers that can forecast both kidney decline and cardiovascular risk has become increasingly urgent.

The research team, led by Shunsuke Inaba and Associate Professor Shintaro Mandai from the Institute of Science Tokyo, focused on microRNAs (miRNAs) found within circulating extracellular vesicles (cEVs). These nanoscale vesicles are released by cells and act as messengers, carrying biological molecules between different parts of the body. As cEVs protect their contents from degradation, they provide a stable source of information about underlying disease processes.

In an initial study involving 36 patients, researchers identified 23 miRNAs that were significantly reduced in cEVs from those with advanced CKD. Many of these miRNAs regulate pathways involved in vascular remodeling, inflammation, metabolic alterations, and cellular aging – all processes implicated in both kidney damage and cardiovascular risk. “We theorized the reduction of these miRNAs in EVs may play a role in the pathophysiology of the underlying mechanisms of CKD and its cardiovascular associations,” explains Inaba.

The M3V2 Equation: A New Risk Model

Through statistical modeling and machine learning, the team narrowed their focus to three key miRNAs that most strongly predicted kidney decline. They then validated these findings in a larger cohort of 234 CKD patients. To further refine their predictions, they combined the miRNA data with measurements of cystatin C and urinary protein-to-creatinine ratio, creating an integrated risk model called the “M3V2 equation.”

Long-term follow-up data, spanning several years, revealed that the M3V2 equation significantly outperformed traditional clinical markers and existing risk classification tools in predicting both kidney decline and major cardiovascular events. Importantly, the model proved effective regardless of the underlying cause of CKD or the presence of pre-existing cardiovascular disease.

“Our results strongly demonstrate the robustness and flexibility of the optimized M3V2 equation in predicting kidney outcomes as well as clinically essential composite events in patients with CKD,” notes Inaba.

Implications for Cardiovascular-Kidney-Metabolic Syndrome

The findings highlight the interconnectedness of kidney and cardiovascular health, supporting the concept of cardiovascular-kidney-metabolic (CKM) syndrome. This syndrome recognizes that dysfunction in one of these systems often impacts the others. The study suggests that changes in miRNA signaling play a crucial role in this interplay, potentially offering new targets for therapeutic intervention.

While the M3V2 equation is not yet ready for widespread clinical employ, the researchers are working to translate their findings into a practical risk score that can be routinely applied in clinical settings. This would allow doctors to identify high-risk patients earlier and implement more aggressive preventive strategies, potentially improving outcomes and reducing premature mortality.

What Comes Next: From Research to Routine Clinical Use

The next steps involve further validation of the M3V2 equation in diverse patient populations and real-world clinical settings. Researchers will as well investigate whether interventions targeting the identified miRNAs can slow CKD progression or reduce cardiovascular risk. The team emphasizes that this research is a step towards personalized medicine for kidney disease, allowing for tailored treatment strategies based on an individual’s unique risk profile. Further research efforts on this topic will help advance personalized medicine for people with kidney disease, thus preventing unnecessary complications and deaths.

Publication details: Shunsuke Inaba et al, Circulating Extracellular Vesicle MicroRNAs as Predictive Biomarkers for Kidney and Cardiovascular Events, Journal of the American Heart Association (2026). DOI: 10.1161/jaha.125.045148

Journal information: Journal of the American Heart Association