A new study suggests that the effects of hypertension or high blood pressure on kidney function can begin much earlier than previously thought — often before any clinical symptoms appear.
Led by researchers from the Medical University of Vienna in Austria, the study highlights the importance of early detection in preventing long-term kidney damage.
The team discovered that hypertension could cause changes to the kidneys, specifically to podocytes — specialised cells in the renal filter — without the presence of other common conditions like diabetes.
Podocytes help regulate the flow of blood and waste through the kidneys. Any damage to these cells can impair the kidney’s ability to filter blood effectively, leading to kidney disease.
The study focused on the structure and density of podocytes to assess kidney health. It revealed that even before symptoms of kidney disease emerge, hypertension can cause podocytes to shrink and their cell nuclei to enlarge.
For their research, the team analysed kidney tissue from 99 patients who had either hypertension and type 2 diabetes or no known kidney conditions.
The tissue samples were taken from patients undergoing tumour nephrectomies, a procedure in which part or all of the kidney is removed to treat cancer. Using advanced imaging techniques and deep learning algorithms, the team was able to closely examine the size, density, and structure of podocytes and the glomeruli (the tiny filters inside the kidneys).
The results were striking. They found that patients with high blood pressure had fewer podocytes compared to healthy individuals, and the podocytes present had enlarged nuclei.
These changes, the researchers noted, were visible even in the absence of diabetes and could indicate the early stages of kidney dysfunction.
This research emphasises that hypertension can cause structural changes to the kidneys before any obvious symptoms show up.
Dr. Rainer Oberbauer and Dr. Heinz Regele, who led the study, stressed that more attention should be given to monitoring kidney health in patients with hypertension, especially since the damage could be happening long before it’s clinically visible.
