Located just below the rib cage on either side of the spine, the kidneys act like a laundry service for your blood. Each bean-shaped organ, about the size of a computer mouse, contains approximately one million tiny filters, or nephrons, that separate the nutrients and other substances your body needs from waste products and excess fluid, which you eliminate as urine.
Chronic kidney disease (CKD) occurs when the organs' tiny filters are progressively damaged over the course of several months to years. Eventually the damage leads to a dangerous buildup of waste in your blood, which can cause inflammation in the blood vessels, setting you up for heart attack, stroke, even brain damage. Without treatment to help slow the progress of the disease, many patients will require either dialysis or a kidney transplant.
One reason CKD is on the rise is that it's linked to two other increasingly common conditions—diabetes and hypertension, which together account for two-thirds of CKD cases. (High blood sugar and high blood pressure damage the kidney's nephrons and impair blood vessel function, making it more difficult for waste to be removed.) But although more and more Americans are being screened for these two conditions, CKD often goes undiscovered until obvious symptoms—such as numbness in the hands or feet, a halt to menstruation, or severe joint pain—appear. The bad news: These symptoms usually don't arise until kidney function has fallen to less than 25 percent of normal and irreversible damage has occurred. The good news: With your doctor's help, you can detect the disease earlier and even prevent it altogether.
What You Can Do
Watch for Warning Signs
Many symptoms of kidney disease are ignored because they don't seem serious. Keep an eye out for loss of appetite, nausea, fatigue, swollen ankles or feet, and difficulty sleeping and concentrating.
Even if you have no symptoms of CKD, you should still get screened if you have diabetes (about 40 percent of those with diabetes develop CKD), high blood pressure, or a family history of kidney disease, or you are over age 60. Screening typically includes a urine test to check for protein, which can show up months to years before symptoms occur. Your doctor may also order a blood test to measure the buildup of waste products (specifically urea and creatinine) as well as an ultrasound of your kidneys.
Block the Damage
To combat diabetes and hypertension, the primary instigators of CKD: Maintain a healthy weight and diet, exercise, and quit smoking. Your doctor may prescribe a special low-salt, low-protein diet, or medication to regulate your blood pressure and blood sugar. (Aim for a blood pressure below 115/75 and a fasting blood sugar below 100.) Also ask your doc to check your levels of hemoglobin A1c, which can indicate the average amount of glucose in your blood over several weeks. One recent study showed that for every 1 percent drop in A1c level, the risk of kidney disease drops by up to 40 percent.
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