Over 30 million people in the United States have a diagnosis of chronic kidney disease and 33% are at risk for CKD. That's one in three. That means when you are driving down the highway, one out of every three drivers that you pass is at risk for chronic kidney disease. And many of them don't even know it and that's because kidney disease is largely a silent disease. Today, I'm going to talk to you about the 5 stages of chronic kidney disease or CKD and what they actually mean for you.
What Do The Stages of CKD Mean?
Now, if you have been diagnosed with Chronic kidney disease or CKD, I'm sure that your doctor has talked to you about what stage you're in. You're in stage III, you're in stage IV, or you're in stage V. What does that mean? Well, if you have CKD, that means that you have either kidney damage or a loss of kidney function that has been occurring for three or more months. The kidneys aren't working the way they should, and they haven't been for three or more months.
What Do The Kidneys Do?
So what exactly are the kidneys supposed to do? What are the kidneys? Where are the kidneys? Well, the kidneys are your two organs that are located in your lower back, in your flanks. They're located where the love handles are. And each kidney is about 9 to 11 centimeters long, and they are literally shaped like kidney beans, two kidney beans. The function of the kidneys is to filter out the blood and to get rid of excess poisons, excess toxins, excess salt, and excess water. When the kidneys aren't filtering the way that they should, then you have some kidney damage. And if this kidney damage lasts for three or more months, you have CKD.
How Do You Know If You Have Chronic Kidney Disease?
Well, a lot of times you won't because CKD is largely a silent disease, meaning you have no symptoms. In fact, most people do not have symptoms until they lose almost all of their kidney function. There may, however, be some symptoms and I want you to watch my YouTube video on the symptoms of kidney disease after you finish reading this post.
Risk Factors For CKD
Since CKD is often such a silent disease, it would also help if you knew if you were a patient who has risk factors.
- The number one risk factor for kidney disease is diabetes.
- Number two is high blood pressure.
- Being over 60 years of age.
- Certain ethnic groups are also at risk, such as blacks and Latinos.
The most important way to know for sure if you have CKD is to see your doctor. When you come to see us, there are certain tests that we perform to let you know if you have CKD and if you are at risk for progressing to end-stage kidney disease.
Kidney Diagnostic Tests
Test for Blood or Protein in Urine
So as a nephrologist, what tests do I do to see if you actually have CKD? Well, one thing is that I test your urine and I test to see if you have blood in your urine or if you have protein albumin in your urine. So blood and albumin, this protein, are actually very large molecules. And when your kidneys are filtering properly, they should not allow blood and this protein to filter out and to get into your urine. So if I see that you have protein or blood in your urine that has come from the kidneys or through the kidneys, then I know that there is some damage to the kidneys. So when you hear your doctor say, "Oh, you have some protein in your urine," that could be an early sign that you have kidney damage, even if your lab work is normal.
Creatinine In Blood
Another early test to screen for CKD is in your blood work, the creatinine. So what is the creatinine? Creatinine is a waste product from muscle metabolism. And the way that creatinine is excreted from your body, the way you get rid of creatinine from your body is through your urine. So when the creatinine level in your blood is too high, we know that the kidneys are not functioning properly because they're not getting rid of the creatinine the way that they're supposed to.
So the creatinine is a marker in the blood to let us know if you have kidney disease. The lower the creatinine, the better, because that means your kidneys are filtering out the creatinine properly. For most patients, a normal creatinine level is around 1.0 or lower, that's just a round number, but you remember I said that the creatinine is based on muscle metabolism. So you can imagine that a big, huge, muscular 21-year-old football player who weighs like 250 pounds would have a greater muscle mass than a very thin 100-pound 80-year-old female.
Glomerular Filtration Rate (GFR)
Another tool to see if you have kidney disease and that is the GFR, the glomerular filtration rate. If you look at your blood work, you'll see it. It'll say EGFR and it will give you a range on what's normal for non-African Americans, and for African Americans. Let me explain. So the GFR or the glomerular filtration rate describes how efficiently your kidneys filter the blood. It literally describes how many milliliters in a minute your kidneys filter. A normal GFR is between 90 and 100 milliliters per minute, and the lower your GFR, the worse your kidney function. So you see, it is the opposite of the creatinine. The higher the creatinine, the worse the kidney function, and the lower the GFR, the worse the kidney function. And it is the GFR that we use to give you your CKD stages.
5 Stages Of Chronic Kidney Disease
Chronic Kidney Disease Stage 1
CKD. 1 is the stage when the kidneys are at their best function and 5 is when the kidneys are functioning at their lowest capacity and where one may need a kidney transplant or dialysis. Stage 1 of CKD is when the GFR is 90 milliliters per minute or greater. So essentially, you have normal kidney function.
So you may be wondering, why are you being labeled as having CKD stage 1 if your kidneys are functioning at a normal capacity? Well, even if the kidneys are functioning at a normal capacity, if you have something abnormal in your kidney anatomy or kidney function, then we still label you as CKD.
So for example, if you have elevated protein in your urine, yet you still have a normal kidney function, we'll call it CKD 1. And if you have abnormal anatomy of the kidney, but you still have a normal kidney function, we'll call it CKD 1. And by abnormal anatomy, you may have polycystic kidneys, multiple cysts, or you may have hydronephrosis when there is a blockage or an obstruction causing a backup of urine in the kidneys.
Chronic Kidney Disease Stage 2
Stage 2 CKD is when the GFR is between 60 milliliters per minute and 89 milliliters per minute. So now you have some mild impairment in kidney function. Even still, most patients usually have no symptoms at this stage, but it is important for the stage to be recognized so that your physician can talk to you about possible risk factors that you could have. For example, if you have diabetes or if you have high blood pressure, you really want to concentrate on managing these diseases so that you won't continue to progress to the next stage of CKD.
Chronic Kidney Disease Stage 3
The next stage is stage 3 CKD or stage 3 chronic kidney disease. Now, this is actually the most common stage of kidney disease. And in stage 3, patients can actually start to develop some symptoms or some lab abnormalities to signify the effects of chronic kidney disease.
Now, again, you could be asymptomatic, have no symptoms in CKD stage 3, but the lower that GFR becomes, the more likely you are to have symptoms, and here are some of the symptoms you may develop in CKD stage 3.
- You may develop fatigue or low energy, and that could be related to anemia or low blood count.
- You could also develop edema or swelling in the feet, and or in the ankles.
- In addition to the lab work being abnormal if you have anemia, having low hemoglobin, you could start to show signs of bone abnormalities.
- You could develop an elevated PTH or parathyroid hormone. And the lower that GFR gets, you can start to develop elevated phosphorus and even abnormal electrolytes, such as elevated potassium. Now, as the GFR gets worse or lower, you may progress to CKD stage 4.
Chronic Kidney Disease Stage 4
For stage 4 chronic kidney disease, the GFR is between 15 milliliters per minute and 29 milliliters per minute. So at CKD stage 4, you can have all of the symptoms that you had in CKD stage 3, only the symptoms tend to get worse. So again, you can have anemia, fatigue, the edema. You can become short of breath, especially if you start holding on to more fluid as the kidneys stop filtering out excess water the way that they should.
And you can certainly get elevated phosphorus in the blood, elevated potassium in the blood. You can even get an abnormal pH balance where your blood becomes too acidic, your carbon dioxide in your blood work can be lower. Once you progress to CKD stage 4, it is time to start having the conversation with your nephrologist and yes, by CKD stage 4, you should certainly be seeing your nephrologist, your kidney doctor on a regular basis.
In CKD stage 4, the discussion of renal replacement therapy is one thing you should be having. What is renal replacement therapy? Dialysis is a form of renal replacement therapy, whether it is in a center with a hemodialysis or at home with home hemodialysis or home peritoneal dialysis, or PD, and kidney transplantation is a form of renal replacement therapy. So certainly by CKD 4, you should have a discussion with your kidney doctor about getting a kidney transplant.
Chronic Kidney Disease Stage 5
Finally, the last stage of CKD is stage 5, and you are in stage 5 CKD when your GFR is less than 15 milliliters per minute. Now, patients in CKD 5, if they have enough symptoms, if their kidneys have gotten to the point where they really do not work efficiently at all, these are the patients who are candidates for kidney transplants and for dialysis, be it hemodialysis or peritoneal dialysis. But just because you are in CKD stage 5, that does not necessarily mean that it is time for a transplant or dialysis. So your kidney doctor, your nephrologist, will see you on a regular basis, and based on your symptoms and your lab work, the decision will be made on whether or not it is time for renal replacement therapy.
Certainly, you should make a decision if you're going to do hemodialysis or the kind of dialysis where you go into the dialysis center three times a week. If you're doing that, certainly even by CKD stage 4, you should have started making preparations to get access or an AV fistula in order to have your hemodialysis treatment. If you've made the decision to do home dialysis or peritoneal dialysis, you want to start making decisions on the access and how to get your PD catheter or peritoneal dialysis catheter.
Even though CKD stage 5 starts when your GFR is less than 15 milliliters per minute, many patients don't actually need to go on dialysis until the GFRs are less than 10 milliliters per minute or even five milliliters per minute. The key is that you must see your kidney doctor on a regular basis at this stage in order to find out when and which intervention is safest for you.
How Do You Know When You Should Be Referred To A Nephrologist?
You must communicate with your primary care doctor. Most primary care doctors if you have CKD stage 1 or CKD stage 2, are able to manage you properly. If you progress to CKD stage 3, it is a good idea to consult with a nephrologist to come up with a game plan on how to slow down the progression of the CKD. And certainly, if you have CKD stage 4 or CKD stage 5, you absolutely should be seeing your nephrologist on a regular basis.
How To Prevent CKD
So is there any way to prevent CKD? Well, yes. The best way to prevent CKD is to see your doctors regularly to find out if you are at risk. 33% of the people in the United States are at risk for kidney disease. And again, many of them don't even know it. So identifying those risk factors like high blood pressure, like diabetes, and managing them, those are ways to help to prevent CKD.
Also identifying family history. If you have a family history of polycystic kidney disease, Alport syndrome, or IgA nephropathy, you should have these discussions with your family members and then go in to see your physician to find out what you can do to help to prevent these things from progressing into the late stages of CKD.
Managing diseases like lupus can help to prevent the progression of CKD. Another very important way to prevent CKD is through diet. Please watch my YouTube video on a proper Kidney disease diet and how to eat right with CKD. So these are the 5 stages of chronic kidney disease. If you found this video to be helpful, please like it and share it with the people you care about. Also, if you have not done so already, please be sure to subscribe to my YouTube channel Dr.Frita and follow me on Instagram @dr.frita. Meanwhile, I want you to do your absolute best to live your healthiest happiest life. I'm Dr. Frita.