If you’re newly diagnosed with chronic kidney disease (CKD), then you may already be aware that there are five progressive stages. But exactly what are these five stages of chronic kidney disease, and what do they mean for you in a practical sense?
How are the 5 Stages of CKD determined?
The first thing to understand is how the stages of renal disease are determined. The health of your kidneys is measured primarily by your estimated glomerular filtration rate (eGFR). GFR is the rate at which fluid is filtered through the kidneys. A higher filtration rate indicates a healthy kidney; a lower rate indicates reduced or suboptimal kidney function, whether due to injury or disease.
Your kidneys’ filtration rates are estimated by the amount of creatinine (cree-AT-uh-neen) in your bloodstream. Creatinine is a waste product of the body’s metabolism of creatine phosphate, a crystalline compound created by everyday muscle movement. The kidneys filter creatinine out of the bloodstream. A serum test will show how much creatinine is in your blood. The higher the level of creatinine, the less of it your kidneys are filtering out. This test is key to estimating your kidney function level.
What are the 5 Stages of CKD based on GFR?
So, now that you know how the five stages of CKD are determined, what are the stages based on eGFR?
In Chronic Kidney Disease Stage 1, your eGFR is 90 or above, meaning that your kidneys are functioning at 90% or better. Your filtration rate is normal, but there might be other indications that not all is well with your kidneys, such as the presence of proteins in your urine.
In Stage 2, your eGFR is between 60 and 89. Your filtration rate is slightly sub-par, and again there might be other indications of inadequate kidney function, but you are still largely asymptomatic in terms of observable changes. There are several tests that your physician can administer to determine the degree of kidney damage and the cause of the lower rate of function, including blood and urine tests, an ultrasound, and a CT scan. At this stage, it’s important to pay attention to your lifestyle habits, especially diet and exercise, as they play a crucial part in determining how fast the disease progresses. Experts recommend that you get your blood sugar and blood pressure checked; eat a healthy diet low in salt, sugar, and processed grains; exercise at least five days a week for a minimum of 30 minutes per day; and quit all forms of smoking and tobacco use.
In Stage 3, your eGFR is between 30 and 59. At this stage, kidney disease can be identified with only a blood test. Stage 3 is often broken down into two phases: Stage 3a (early), during which your eGFR is between 45 and 59, and Stage 3b (late), during which your eGFR is between 30 and 44. During Stage 3, you may or may not be symptomatic. If symptoms do appear, they are more likely to do so during Stage 3b, and may include:
- back pain
- swollen hands and/or feet
- unusually frequent or infrequent urination
As kidney function decreases, and wastes build up in your body, other adverse health conditions may develop, such as:
- high blood pressure
- bone disease
Stage 3 is a good time to consult a nephrologist – a kidney specialist – to devise, and begin implementing, a treatment plan. Treatment for CKD focuses on preventing disease progression, and largely consists of managing conditions that can complicate, or result from, the disease. In addition to the conditions mentioned above, these can also include:
- high cholesterol
A treatment plan for CKD usually involves a combination of diet changes, adjustments in exercise frequency and intensity, and prescriptions of both medications and dietary supplements.
In Stage 4, your eGFR is between 15 and 29. By now you should be making regular visits to your nephrologist and maintaining your treatment plan. In this stage, you and your doctor should begin discussing your options in the event of kidney failure. There are two basic options at this point: dialysis or a kidney transplant. But you have options within those options.
There are two types of dialysis: hemodialysis and peritoneal dialysis. Hemodialysis is generally done in a medical environment and involves the use of a machine. Your blood flows into the machine, the machine cleanses it of impurities, and the clean blood is returned to your body. Peritoneal dialysis is generally done at home, and involves the introduction of a cleansing agent through a catheter into the lining of your abdomen. The preparation for peritoneal dialysis requires minor surgery, however, for the insertion of the catheter.
A kidney transplant has pros and cons. On one hand, a new working kidney filters wastes from the bloodstream more efficiently than dialysis can. On the other hand, patients can wait for years before an appropriate donor becomes available, and not every patient with kidney failure is a good candidate for a transplant. Your age, cognitive status, and other health conditions may make you ineligible. Keep in mind that, even if you’re approved for a transplant, and a kidney is available, a transplant is not a cure. You’ll still need to take medications daily to ensure that your immune system doesn’t reject the new kidney.
In Stage 5, your eGFR is less than 15, and your body has gone into total kidney failure, or is about to. Without functioning kidneys, waste products that have been collecting in your bloodstream reach toxic levels. Some symptoms of kidney failure include those associated with Stage 3 (see above), and also:
- diminished appetite
- muscle cramps
- disturbed sleep
- breathing trouble
- nausea and vomiting
Stage 5 is the point at which you must either begin dialysis or receive a kidney transplant. This is not a time for despair, and you are not alone on this journey. Nearly 750,000 people in the U.S. and 2 million people worldwide navigate Stage 5 kidney disease (also called end-stage renal disease) every year. Many people with CKD live enjoyable, productive lives whether on dialysis or post-transplant. While life expectancy tends to be longer with a transplant, some patients on dialysis have been known to live up to 20 or 30 years after starting treatment. The important thing to remember is that, with careful planning and the help of your support network, there is hope.