The renal arteries supply blood to the kidneys. They branch from the main artery that carries blood from the heart to the lower body. Before reaching the kidneys, each renal (kidney) artery divides into four or five branches. Renal (kidney) artery disease (RAS) occurs when blood flow to one or both kidneys is restricted or blocked as a result of atherosclerosis, the buildup of plaque in the arteries. When blood flow to the kidneys is restricted or blocked by atherosclerosis in the renal arteries, the kidneys are deprived of the nutrients and oxygen they need to function.
RAS is similar to heart, or coronary, disease: Both are the result of atherosclerosis, often called "hardening of the arteries.” During the process of atherosclerosis, arteries become thickened and narrow due to the buildup of plaque on their inside walls, and over time, they lose their flexibility. As a result, the size of the channel through which blood flows becomes smaller and blood flow is restricted.
Smoking, high cholesterol, high blood pressure, diabetes, a high-fat diet, lack of physical activity, obesity, age, and a family history of heart disease are factors known to increase your risk of developing atherosclerosis. If you have been diagnosed with narrowing of arteries that supply blood to your heart (coronary artery disease), brain (carotid artery disease), or legs (peripheral artery disease), you are also at increased risk for RAS.
Risk Factors You May Be Able to Control
- Smoking. It’s time to quit. Try the SecondsCount Smoke-Free Success Plan.
- Diabetes. If you have diabetes you are at greater risk for RAS and heart disease. Work with your doctor to carefully manage your diabetes.
- High blood pressure and high cholesterol. Make a point to have your blood pressure and cholesterol checked regularly.
- Lack of physical exercise. Make time to exercise. It will improve you overall health and help you manage your diabetes, blood pressure, and cholesterol.
- Being overweight or obese. Men and women who are overweight are about 20 percent more likely to develop cardiovascular disease. If you are overweight, SecondsCount Heart-Healthy Eating Guidelines are a great way to ease into losing those extra pounds.
Risk Factors You Can’t Control
- Family history of cardiovascular disease. Ask your doctor if your family history puts you at greater risk for RAS.
- Age. Atherosclerosis is a process that continues as you age. The older you are, the more time fatty deposits have had an opportunity to build up in your arteries.
Because RAS and coronary, carotid, and peripheral artery disease (PAD) are all caused by the process of atherosclerosis, If you’ve already had a blockage or narrowing of the coronary, carotid, or peripheral arteries, you are at increased risk of having similar problems with the arteries that carry blood to your kidneys. To learn more about minimizing your risk factors for RAS and other cardiovascular diseases, visit SecondsCount’s section on Risk Factor Modification.