How do diabetes and high blood pressure damage the kidneys?

Diabetes and high blood pressure damage the kidneys through distinct but often overlapping mechanisms that impair the organ's ability to filter waste from the blood.

Diabetes and the Kidneys

In diabetes mellitus, chronic high blood sugar (hyperglycemia) leads to the formation of harmful substances known as advanced glycation end products (AGEs). These substances damage the blood vessels within the nephrons, the functional units responsible for filtration. Over time, this process—known as diabetic nephropathy—causes the kidneys to lose their filtering capacity, often signaled by the leakage of the protein albumin into the urine.1

High Blood Pressure and the Kidneys

High blood pressure (hypertension) causes nephrosclerosis, a condition characterized by the hardening and thickening of the walls of the small arteries and arterioles in the kidney. This process restricts blood flow to vital kidney tissues, leading to gradual scarring and deterioration. In cases of malignant hypertension, this damage occurs rapidly, causing severe destruction of renal substance.23

When diabetes and hypertension occur together, they significantly accelerate the progression toward kidney failure.1