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Jason Merritt, M.D., The Nephrology Clinic, P.C.

Kidney disease, or the increased risk of CKD, is not something to ignore, says Dr. Merritt, since kidneys are vital to good health. The kidneys are hard working organs. They balance body fluids, filtering excesses out of the blood through urination. They regulate body water and minerals in the blood such as sodium, potassium, phosphorus, and calcium. They remove waste products from the blood, help expel drugs and toxins from the body, release hormones that control blood pressure, make red blood cells, and keep bones healthy.

The two most common causes of CKD are diabetes and high blood pressure, and CKD is a condition that increases the chance of premature death. “People with CKD are more likely to develop heart disease,” Dr. Merritt says, “and this is the number one cause of death among kidney patients.”

The good news is that early detection and treatment can keep kidney disease from worsening and can prevent life-threatening complications such as kidney failure and heart disease. But, because symptoms may not show up until late in the game, CKD often goes undiagnosed. In the past, early diagnosis was inhibited by the lack of a universal definition and classification system for the stages of CKD. In 2002, the National Kidney Foundation created definitions and guidelines that would help doctors make appropriate diagnosis in its Kidney Disease Outcomes Quality Initiative (KDOQI).

“Before the National Kidney Foundation came out with its guidelines and stages of CKD, it was just classified as renal insufficiency,” Dr. Merritt says. “Now there are specific levels of disease and also a corresponding action. For example, in the first two stages, we focus on diagnosing the cause and limiting its progression. When it gets to stage three, or less than 60% of normal function, we look at treating the complications.”

Early diagnosis is essential, he says. “The sooner diagnosis is made, the less likely it will progress to the need for dialysis.”

While most people don’t experience severe symptoms until kidney disease is in the last stages, there are some symptoms that might cause concern. Those include feeling more tired than usual, having trouble concentrating or thinking clearly, or poor appetite. Other indicators can be nighttime muscle cramps, swollen feet and legs, or a foamy quality to the urine.

Even without symptoms, it is wise to get a check-up. “Get your annual physical and blood work,” Dr. Merritt says. “That will typically include a creatinine level, which is a marker of kidney function.”

Creatinine is a waste product created through muscle activity and then eliminated through urination. The results of the blood creatinine test are used to estimate the glomerular filtration rate, or GFR, which indicates the level of kidney function. A low GFR may mean that the kidneys are not working as well as they should to remove wastes. Analysis of the urine can also detect whether protein in being excreted, which if present can indicate compromised kidney function.

Using the GFR as a standard, the National Kidney Foundation established five stages of chronic kidney disease. In stage one, there is some kidney damage (for example, protein in the urine) but GFR is normal (more than 90 mL/min). Stage two indicates kidney damage with a mild decrease in GFR (60 to 89). Stage three reflects a moderate decrease in GFR (30 to 59). Stage four indicates a severe decrease in GFR (15 to 29) and stage five is considered kidney failure when dialysis or a kidney transplant is needed.

There is more to the interpretation of GFR results than just the number, however. “The problem is that the lab has to account for everyone from a 25-year-old male bodybuilder to a 95-year-old female with no muscle mass. So the range of creatinine values is large,” Dr. Merritt says. “Creatinine has to be interpreted based on age and muscle mass. In other words, the interpretation has to be individualized.”

That’s what nephrologists do, he explains. That and education. “We do our best to educate other physicians as to what chronic kidney disease is and when patients should be referred to a nephrologist.”

Patients also have to be educated. “Initially, a lot of patients do not see their diabetes and hypertension as systemic diseases capable of damaging other organs, such as the kidneys. However, after being diagnosed with chronic kidney disease, these patients tend to pay more attention to their blood sugar and blood pressure. Their primary care doctor may have already told them that poor blood sugar or blood pressure control could result in kidney damage. But until they hear the CKD diagnosis, they are often not as vigilant or compliant as they need to be.”

Diagnosis is half the battle. Action is the other half. “You can slow the progression of chronic kidney disease,” Dr. Merritt says. “This can be done through tighter blood sugar and blood pressure control, use of specific medications to decrease the protein in the urine, and avoidance of a few over-the-counter medications which can be harmful to the kidneys.”

Dr. Jason Merritt examines a patient. More than 20 million Americans have been diagnosed with chronic kidney disease.

The National Kidney Foundation lists several ways to lower the chances of developing kidney disease. First, patients must carefully follow prescribed treatments to control diabetes and/or high blood pressure. Losing excess weight with a healthy diet and regular exercise program is also a must. Smoking is a major contributor. So, if you’re a smoker, stop. Other ways to lower chances include avoiding use of large amounts of over-the-counter pain relievers and limiting the intake of alcohol.

Even with a diagnosis of CKD, early detection and treatment can often stop or slow the progression of the disease. Treatment depends on the stage of CKD and other concurrent health problems, but some common efforts that doctors may recommend include:

• Control of high blood pressure. That may require medication such as an angiotensin converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB). Limiting the amount of salt in your diet also helps.
• Control of blood sugar if diabetic.
• Following a special diet that controls the amount of protein and saturated fat consumed. Registered dietitians can help plan meals that include appropriate quantities and are aimed at weight control.
• Treatment of anemia with iron supplements and erythropoietin (EPO). EPO stimulates red blood cell production.
• Preventing bone disease with balanced phosphorus and calcium levels. The kidneys normally remove excess amounts of phosphorus, but when they aren’t working well it can build up, ultimately leading to a loss of calcium from the bones. Doctors may recommend dietary restrictions or may prescribe medication.
• Following a doctor-recommended exercise program.
• Taking steps to prevent heart problems, including treatment of diabetes, high blood pressure, anemia, and high cholesterol levels.
• Smoking cessation.

How well the treatment achieves its goal depends on several things. The earlier treatment is started, the better. Results also depend heavily on how carefully the treatment plan is followed.

Dr. Merritt encourages anyone at risk or with CKD to talk to his/her primary care doctor. “Primary care physicians in this area really do a good job trying to get people more involved in their own health care. And they can also tell you when it’s time to see a nephrologist. The main thing is to get educated and get active.” +