5 Stages of Kidney Disease: What Nephrologists Want You to Know
If you've recently learned that you have chronic kidney disease (CKD), you're probably more than a little overwhelmed. But once you've been diagnosed, your doctor will explain a crucial aspect of your condition: the "stage" of your disease.
"It's really important to know this, so you can take the right steps to get your CKD under control, or at least slow its progression," says Richard Glassock, MD, professor emeritus at the David Geffen School of Medicine at UCLA and past President of both the American Society of Nephrology and the National Kidney Foundation (NKF).
What are the stages of chronic kidney disease?
There are five main stages of kidney disease ranging from very mild (stage 1) to kidney failure (stage 5). They're based on how well your kidneys work to filter out waste and fluid from your blood, Dr. Glassock tells Health.
Your doctor can determine which stage you're at by measuring your glomerular filtration rate (GFR), also known as an eGFR, or estimated glomerular filtration rate. According to the NLM, this test checks how well your kidneys are working by estimating how much blood passes through your glomeruli—the tiny kidney filters that remove waste and fluid from your blood—each minute. It then calculates how much creatinine, a waste product, is found in your blood. That level, along with other factors, including your age, race, and gender, determine your GFR.
Here's a look at the different stages, and what it means for you.
GFR levels: 90 or above
If you have stage 1 kidney disease, it means your kidneys are working well but you have signs of mild kidney damage, says the American Kidney Fund (AKF). At this stage, you probably don't have any symptoms, other than protein in your urine if you take a urine test in your doctor's office. Other warning signs may be high blood pressure or swelling in your legs, Robert Greenwell, MD, chief of nephrology at Mercy Medical Center in Baltimore, tells Health.
What to do: deal with underlying medical conditions. "High blood pressure and type 2 diabetes are two of the most common causes of stage 1 chronic kidney disease," so it's really important to take steps to get them under control," stresses Dr. Greenwell. It's important to lose weight, exercise regularly, eat a healthy diet, and stop smoking if you do so. You may also need to go on high blood pressure or diabetes medication to control those diseases, as well.
GFR levels: between 60 and 89
The good news is your kidneys are still healthy and working well; the bad news is they are showing clear signs of physical damage, and some people still don't have any symptoms, says Dr. Glassock. But you may notice that you're running to the bathroom more than usual, and if you do take a urine test, it will show elevated albumin levels, which is the main protein in your blood.
"Healthy kidneys remove extra fluid and waste from your blood, but let proteins return to your blood stream," explains Dr. Glassock. "When they're damaged," he says, "they let albumin escape through their filters, so they end up in your urine." Since protein helps control the amount of fluid in your body, you may notice fluid building up, particularly in your calves, ankles (cankles), and feet.
What to do: at this point, treatment is pretty much the same as stage says Dr. Glassock. If you have high blood pressure, you may already be on hypertension meds like angiotensin-converting enzyme inhibitors (ACE inhibitors) and angiotensin receptor blockers (ARBs). But if you don't, your doctor may recommend that you go on them now. "These drugs also help to protect your kidneys from further damage," explains Dr. Glassock.
GFR levels: between 30 and 59
When you reach this stage, your kidneys are showing real damage. As a result, they're not working as well as they should, says Dr. Glassock. Stage 3 is separated into two stages: Stage 3a means you have a GFR between 45 and 59, and Stage 3b is a GFR between 30 and 44. Along with the symptoms that may occur during stage 1 and stage 2, Dr. Glassock says you also have increased risk of these two serious health conditions:
* Osteoporosis. Since your kidneys can't filter out waste like they normally do, levels of important bone-building minerals like calcium and phosphorus get out of whack. This puts you at increased risk of developing bone disease.
* Anemia. One out of seven people with CKD go on to get this disease, and it often shows up at this late stage, says Dr. Glassock. Here's why: When you have kidney disease, your kidneys cannot make enough of a hormone known as EPO, which is what helps your body develop red blood cells, he explains. As a result, your red blood cell count drops. You're especially at risk if you are over age 60 and/or have type 2 diabetes.
What to do: all the steps you took during stage 1 and stage 2—control your diabetes and blood pressure, don't smoke, eat a healthy diet, and be active most days of the week—are still vital, stresses Dr. Glassock. If you haven't yet met with a dietitian, you'll want to do so now.
It's very important that you avoid foods high in sodium, potassium, and phosphorus, as these can all worsen existing CKD, the Cleveland Clinic points out. You will also need to limit protein, as that can put a lot of strain on your kidneys, notes NKF. You also might need to limit fluid, as damaged kidneys have trouble removing it, which means it can build up in your body, says the NLM.
GFR levels: between 15 and 29
If you have stage 4 CKD, your kidneys are severely damaged. This is the last stage before kidney failure. Along with the symptoms seen in stage 3, you may develop jaundice, including a yellowing of the whites of your eyes, says the NKF. Other health conditions like osteoporosis and anemia can worsen, the NKF.
What to do: your doctor should run blood tests frequently to check levels of calcium, phosphorus, vitamin D, says the NFK. Another hormone they may check is your parathyroid hormone (PTH). PTH pulls calcium from your bones to try and "fix" the fact that you don't have enough in your blood. As a result, this can lead to bone disease, says the AKF.
You should also talk to them about having a bone density scan to check for osteoporosis. If you have other conditions that can worsen kidney disease, like high blood pressure or type 2 diabetes, it's important to get them under good control now.
You'll also need to go on dialysis, which is a procedure that uses machines to remove waste products from your body when your kidneys no longer can. There are two major types of dialysis:
* Hemodialysis. Your blood is circulated through a machine to remove waste and fluid, then returned to your body. It's done at a clinic and is very time intensive: three to four hours, at least three times a week, says NKF.
* Peritoneal dialysis. A dialysis solution is run directly into your stomach to absorb waste, which is removed via a catheter. You can do this type of dialysis yourself, at home. Most people choose to do it when they're asleep so they can continue working and doing other activities during the day, says NKF. But it's not for the squeamish: you need to be comfortable running the machine and inserting and removing equipment from your abdomen.
GFR: less than 15
If you have stage 5 chronic kidney disease, that means you are in kidney failure. Since your kidneys are no longer working, waste builds up in your blood, which can make you very sick. If left untreated, you'll die, says Dr. Glassock. The AKF, Mayo Clinic, and others say symptoms at this stage include:
- Peeing more or less than normal
- Swelling in your lower body due to fluid retention
- Shortness of breath
- Irregular heartbeat
- Sometimes, even seizures or coma
What to do: there are only two options at this point, dialysis or kidney transplant. "Of these two, kidney transplantation is considered the treatment of choice because it offers better quality of life and survival rates," says Dr. Greenwell.
But there's a national kidney shortage, so you'll need to be placed on a transplant waiting list and will have to continue dialysis until a kidney becomes available. A kidney can be transplanted from either a live or dead person, but in general kidneys from living donors work better and for longer, notes Dr. Greenwell. Sometimes, a family member or friend may even opt to donate a kidney, since you only need one to survive.
There are some reasons, though, why you may not be a candidate for a kidney transplant. Per Mayo Clinic, these include:
- Heart disease
- Active of recent cancer
- Alcohol or drug abuse
- Advanced age
- Other conditions that may affect a person's ability to undergo surgery take anti-rejection medicines
In these cases, you'll most likely need to stay on dialysis for the rest of your life. If you do qualify for a kidney transplant, and do get one, there will still be challenges post-surgery, stresses Dr. Greenwell. You'll need to take medications for the rest of your life to prevent your body from rejecting your new kidney. This can lower your immune system, raising your risk of severe infections and even some cancers.
After kidney transplantation, you will be required to take medications and have frequent monitoring to minimize the chance of organ rejection; this must continue for your entire lifetime. The medications can have significant side effects, including increased risk of severe infections, diabetes, and some cancers, says NKF.
You'll also need to stay vigilant against COVID-19, as a study published in May in JAMA found that the vaccine only provides limited protection for organ transplant patients.
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