How does diabetes lead to changes in the kidney over time?

Chronic diabetes, particularly when blood sugar levels are inadequately managed, has a profound impact on kidney health over time. Elevated glucose levels can lead to a condition known as diabetic nephropathy, which is characterized by damage to the nephrons—the functional filtering units of the kidneys.

High levels of glucose cause biochemical changes that result in injury to the nephrons and surrounding structures. This process is often mediated by the production of harmful substances, such as advanced glycation end products (AGEs), which can lead to inflammation and fibrosis of kidney tissues. As a result, the ability of the kidneys to efficiently filter waste and excess fluid is impaired, leading to a gradual decline in kidney function.

This deterioration can progress without significant symptoms until it reaches advanced stages, where patients may develop symptoms such as fluid retention, high blood pressure, and proteinuria (excess protein in urine), indicating significant nephron damage. Thus, the fundamental mechanism by which diabetes leads to kidney changes lies in the direct damaging effect of persistent high glucose levels on the nephron's structure and function.