Scientists have finally uncovered a solution to a longstanding medical mystery: why more than half of patients with chronic kidney disease (CKD) eventually succumb to cardiovascular complications. Researchers from UVA Health and Mount Sinai have identified that diseased kidneys produce a specific substance that essentially “poisons” the heart.
This discovery is a significant milestone in nephrology and cardiology. It could allow doctors to identify at-risk patients much earlier. Doctors will be able to develop targeted treatments to prevent heart failure.
The Silent Link Between Kidneys and Heart Failure
Chronic kidney disease is a massive public health challenge, affecting approximately 35 million Americans—or about 1 in 7 people. The connection between CKD and cardiovascular issues is well-documented. However, determining the exact cause has been difficult. Shared risk factors like obesity and hypertension often cloud the results.
Dr. Uta Erdbrügger, a researcher at the University of Virginia School of Medicine, emphasises that both diseases often develop silently. Consequently, damage is frequently already done by the time they are diagnosed. This new research provides a specific “culprit” that links the two organs directly.
The Discovery: Toxic “Extracellular Vesicles”
The researchers identified that diseased kidneys release particles known as circulating extracellular vesicles (EVs). While EVs normally act as messengers carrying proteins between cells, those produced by kidneys with CKD carry a specific type of toxic material: small, non-coding RNA called miRNA.
Key findings from the study include:
Heart Toxicity: These vesicles travel through the bloodstream from the kidneys to the heart, where the miRNA they carry proves toxic to cardiac tissue.
Successful Lab Trials: In studies involving mice, blocking these vesicles from circulating resulted in significantly improved heart function and a reduction in heart failure symptoms.
Human Confirmation: The team confirmed the presence of these harmful vesicles in blood plasma samples donated by human CKD patients, whereas healthy participants did not show the same toxic markers.
The Future of Treatment: Precision Medicine and Blood Tests
This breakthrough opens the door to precision medicine for kidney patients. Dr. Erdbrügger and her colleagues hope to translate these findings into practical clinical tools, such as:
1. New Biomarkers: A simple blood test could potentially identify CKD patients at the highest risk for heart problems before symptoms appear.
2. Targeted Therapies: Scientists may be able to develop drugs that specifically target or “block” these circulating vesicles, preventing them from poisoning the heart.
3. Earlier Intervention: By identifying the risk early, doctors can implement treatments that improve overall patient outcomes and survival rates.
Key Statistics: Chronic Kidney Disease in the US
| Group | Prevalence of Kidney Disease |
| Total US Population | 1 in 7 (approx. 35 million) |
| Patients with Diabetes | 1 in 3 |
| Patients with Hypertension | 1 in 5 |
FAQ: Understanding the Kidney-Heart Connection
How exactly do kidneys damage the heart? Diseased kidneys release “extracellular vesicles” containing toxic miRNA. These particles travel through the blood and interfere with heart function, leading to heart failure.
Why was this so hard to discover? It was difficult to pinpoint a kidney-specific cause because patients often have other conditions, such as high blood pressure and obesity, which also damage the heart.
Is there a test for this yet? Not yet. However, researchers are currently working to develop blood tests based on these toxic vesicles to help screen patients at high risk.
What is the next step for this research? Dr. Erdbrügger is organising a specialised workshop at UVA starting 7 February to advance extracellular vesicle research. Furthermore, the Paul and Diane Manning Institute of Biotechnology is working to accelerate these lab discoveries into lifesaving treatments.
Frequent Questions
What is the main cause of death in kidney disease patients? More than half of patients with chronic kidney disease die from cardiovascular problems rather than kidney failure itself.
What are extracellular vesicles? They are tiny particles produced by almost all cells that act as messengers, carrying proteins and genetic material to other parts of the body.
Can heart failure from kidney disease be prevented? While research is ongoing, the discovery of toxic miRNA suggests that blocking these particles could eventually prevent heart damage in CKD patients.
