High BP can damage kidney functions even before symptoms appear: Study

New Delhi, March 29
Hypertension or high blood pressure can have a significant impact on kidney function, much before clinical symptoms begin to appear, according to a study that stressed the importance of early detection.

The research, led by a team from the Medical University of Vienna in Austria, found that high blood pressure can lead to abnormalities in the podocytes -- specialised cells in the renal filter -- even without other pre-existing conditions such as diabetes.

"Early detection and treatment could help to slow the progression of kidney disease and prevent long-term damage," said the researchers Rainer Oberbauer and Heinz Regele from the varsity.

For the study, published in the journal "Hypertension", the team analysed kidney tissue from a total of 99 patients: who either suffered from high blood pressure (arterial hypertension) and type 2 diabetes or did not have either of the two conditions. High BP and diabetes are the most common causes of chronic kidney disease.

The study was conducted on unaffected renal tissue samples from tumour nephrectomies -- a surgical procedure in which a kidney is removed in whole or in part to treat a kidney tumour.

Using modern imaging and computer-assisted methods, the size and density of the podocytes and the volume of the renal corpuscles (glomeruli) were determined in the tissue samples.

Podocytes are specialised cells of the renal corpuscles (glomeruli) that play a crucial role in the filtering function of the kidney. Their size and density are important indicators of the health of the kidney tissue.

Artificial intelligence in the form of deep-learning-based image analysis was used for the analysis. With the help of a specially trained algorithm, digital tissue sections were automatically analysed to precisely capture the structure of podocytes and glomeruli.

"The results show that patients with hypertension have a reduced density of podocytes compared to healthy controls and that their cell nuclei are enlarged compared to those of healthy controls," said first author Christopher Paschen.

These changes occurred independently of the additional diagnosis of type 2 diabetes and likely represent the first microscopically visible step towards impaired renal function.

This indicates that high blood pressure can cause structural damage to the kidneys at an early stage and before clinical symptoms appear, the researchers explained.