Each year in the United States, nearly 100,000 people are diagnosed with kidney failure, a serious condition in which the kidneys fail to rid the body of wastes. Kidney failure is the final stage of a slow deterioration of the kidneys, a process known as nephropathy.

Diabetes and Kidney Disease: Understanding the Kidneys

The kidneys act as filters to clean the blood. They get rid of waste and extra fluid. The tiny filters throughout the kidneys are called glomeruli.

When kidneys are healthy, the arteries brings blood and waste from the bloodstream into the kidney. The glomeruli clean the blood. Then waste and extra fluid go out into the urine through the ureter. Clean blood goes out of the kidney and back into the bloodstream through the veins.

Diabetes and Kidney Disease: The Course of Kidney Disease

Diabetic kidney disease takes many years to develop. In some people, the filtering function of the kidneys is actually higher than normal in the first few years of their diabetes. This process has been called hyperfiltration.

Over several years, people who are developing kidney disease will have small amounts of the blood protein albumin begin to leak into their urine. At its first stage, this condition has been called microalbuminuria. The kidney’s filtration function usually remains normal during this period.

As kidney disease progresses, more albumin leaks into the urine. Various names are attached to this interval of the disease, such as overt diabetic nephropathy or macroalbuminuria. As the amount of albumin in the urine increases, filtering function usually begins to drop. The body retains various wastes as filtration falls. Creatinine is one such waste, and a blood test for creatinine can measure the decline in kidney filtration. As kidney damage develops, blood pressure often rises as well.

Overall, kidney damage rarely occurs in the first 10 years of diabetes, and usually 15 to 25 years will pass before kidney failure occurs. For people who live with diabetes for more than 25 years without any signs of kidney failure, the risk of ever developing it decreases.

Diabetes and Kidney Disease: The Effects of High Blood Pressure

Diabetes and Kidney Disease: An Overview Preventing and Slowing Kidney Disease Dialysis and Transplantation

High blood pressure, or hypertension, is a major factor in the development of kidney problems in people with diabetes. Both a family history of hypertension and the presence of hypertension appear to increase chances of developing kidney disease. Hypertension also accelerates the progress of kidney disease in people who already have it.

In the past, hypertension was defined as blood pressure exceeding 140 millimeters of mercury-systolic and 90 millimeters of mercury-diastolic. Professionals shorten the name of this limit to 140/90. The terms “systolic” and “diastolic” refer to pressure in the arteries during contraction of the heart (systolic) and between heartbeats (diastolic).

The American Diabetes Association and the National Heart, Lung, and Blood Institute recommend that people with diabetes keep their blood pressure below 130/80.

Hypertension can be seen not only as a cause of kidney disease, but also as a result of damage created by the disease. As kidney disease proceeds, physical changes in the kidneys lead to increased blood pressure. Therefore, a dangerous spiral — involving rising blood pressure and factors that raise blood pressure — occurs. Early detection and treatment of even mild hypertension are essential for people with diabetes.