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How can diabetes mellitus cause kidney failure or vision loss?

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Health monitoring — human disease The routine monitoring of blood pressure levels is an important part of assessing an individual's health. Blood pressure provides information about the amount of blood in circulation and about heart function and thus is an important indicator of disease.

Diabetes mellitus causes kidney failure and vision loss primarily through microangiopathy, a condition where chronic high blood sugar (hyperglycemia) damages small blood vessels throughout the body.12

Vision Loss

In the eyes, this damage leads to diabetic retinopathy. Excess glucose causes retinal blood vessels to weaken and leak fluid, potentially leading to swelling (macular edema) or ischemia (reduced blood flow). In advanced stages, the body attempts to compensate by growing new, fragile blood vessels that are prone to bleeding, which can cause retinal detachment, glaucoma, and permanent blindness.34

Kidney Failure

In the kidneys, the condition is known as diabetic nephropathy. High blood sugar and hypertension damage the nephrons—the functional units responsible for filtering waste from the blood. Over time, this causes the vessels to become leaky and eventually obstructed. As the kidneys lose their ability to filter waste, the condition can progress to end-stage renal disease, or kidney failure, where function is severely reduced or lost entirely.51

Controlling blood glucose levels and blood pressure is essential to slowing or preventing these complications.15