The disorder continues to progress, with end-stage renal disease developing within 2 to 6 years after the appearance of chronic renal failure or significant hypertension. The mechanism that causes diabetic nephropathy is unknown. It may be caused by inappropriate incorporation of glucose molecules into the structures of the basement membrane and the tissues of the glomerulus. The disorder affects about 4 out of 10,000 persons. The risk is related to the control of the blood-glucose levels .
Risk is higher if glucose is poorly controlled than if the glucose level is well controlled.
Nephropathy may be present for many years before nephrotic syndrome or chronic renal failure develops. Nephropathy is often diagnosed when routine urinalysis shows protein in the urine, indicating renal dysfunction. Control of blood pressure is even more important than control of blood-sugar. There may be no symptoms for many years. There may or may not be signs of other diabetic complications.