Complications of diabetes: kidney disease
About one in every four people with diabetes — regardless of the type — will develop kidney disease at some point in their life. Also known as nephropathy, kidney disease is most common among people who have had poorly controlled blood glucose for many years.
The kidneys are organs that remove potentially toxic substances from the blood. Most people are born with two kidneys, located on either side of the lower back.
A gradual decline
Kidney disease progresses through five stages, ranging from mild to complete kidney failure. During each stage, your doctor will perform blood tests to measure how quickly your kidneys filter toxins from your blood. This measurement is known as your glomerular filtration rate, or GFR. As you proceed through the stages of disease, your GFR will gradually become lower as your kidneys become less effective at filtering toxins from your blood.
|Stage||GFR (mL/min)||Condition of the Kidneys|
|1||90 or Higher|
The kidneys function normally, but the person is at risk for kidney disease.
|2||60-89||Mild decline in kidney function|
|3||30-59||Moderate decline in kidney function|
|4||15-29||Severe decline in kidney function|
|5||14 or Lower||Kidney failure|
Your doctor may express concern about your likelihood of developing kidney disease if routine urine tests repeatedly reveal the presence of protein.
Symptoms are rare during the mildest stages of kidney disease, but you might notice your blood pressure rises. During this time, a routine blood test might reveal that your kidneys are filtering blood less quickly than they used to.
If blood tests reveal a moderate decrease in your GFR, you may still have time to slow the development of kidney disease by improving your blood glucose or blood pressure control.
If you take metformin, your doctor will probably switch you to a different medication, because metformin is not safe to use in people with more advanced kidney problems.
People with severe kidney disease often develop high blood pressure and may begin to need more insulin than they used to. A blood test will reveal that the kidneys are filtering blood very slowly.
As you progress further, your kidneys will continue to slow down and become less effective. Because toxins are not as readily cleared from the body, fluid retention becomes a problem. You may find that you actually need less insulin. You’ll have less energy and you may feel nauseous, especially in the mornings. Your doctor will work hard to control your blood pressure and help you manage your blood glucose.
When you reach the point where your kidneys can no longer function well enough on their own, you will need to start dialysis. A dialysis machine can take over the kidney’s job of filtering toxins from the blood.