Most people know that high blood pressure puts you at greater risk for heart attack and stroke. But you might be surprised to learn that high blood pressure can also damage the kidneys.
High blood pressure (140/90), also called hypertension, is a leading cause of kidney disease in the United States. Neither high blood pressure nor kidney disease usually has symptoms. The best way to protect your kidneys is to have your blood pressure checked regularly.
High blood pressure can damage the tiny blood vessels in the kidneys that filter waste out of the blood. This affects the kidneys' ability to function and causes wastes to build up. The damage usually occurs slowly, over many years, and may not cause any symptoms at first, says the National Heart, Lung, and Blood Institute (NHBLI). Often the only way to find out whether the kidneys have been damaged is with one of two tests: a urine test or a blood test.
Since high blood pressure doesn't cause symptoms for many years, a lot of damage is done to the kidney vessels before treatments are started. By then, the kidney vessels are so scarred they will not heal. If the kidneys fail completely, the only options are dialysis or a kidney transplant. The NHLBI says that high blood pressure causes more than 25,000 new cases of kidney failure, or end-stage renal disease, every year. If kidney disease is caught in the early stages, though, it is possible to take steps to help the kidneys function for as long as possible. One of the most important ways to maintain kidney function is by controlling blood pressure. The NHLBI considers people with diabetes or chronic kidney disease who have a blood pressure higher than 130/80 mm Hg as hypertensive.
All Americans with high blood pressure are at risk for kidney disease, but African Americans are more likely than whites to develop kidney disease as a result of hypertension. People with diabetes and those who have a history of kidney disease in their family are also at a higher risk for kidney failure.
Many people can keep their blood pressure under control by making lifestyle changes. These changes include maintaining a healthy weight, limiting daily sodium intake, exercising, quitting smoking, reducing stress, and limiting alcohol consumption. For others, lifestyle changes are not enough to reduce blood pressure levels. They may need to take medications to accomplish this.