About 37 million American adults have chronic kidney disease, yet as many as 9 in 10 don’t know they have it. According to the CDC, chronic kidney disease — often abbreviated CKD — is one of the most underdiagnosed conditions in the country, silently damaging the kidneys for years before symptoms appear. By the time many people are diagnosed, significant and irreversible kidney damage has already occurred. Early detection and management are the most powerful tools available to slow progression and preserve kidney function. For more on chronic conditions, see our medical conditions guide.
What Is Chronic Kidney Disease?
Chronic kidney disease is a condition in which the kidneys gradually lose their ability to filter waste and excess fluid from the blood. Your kidneys — two fist-sized organs near the middle of your back — filter about 200 quarts of blood daily, removing waste products, balancing electrolytes, regulating blood pressure, stimulating red blood cell production, and maintaining bone health. When kidney function declines, these processes are compromised.
CKD is defined as kidney damage or reduced kidney function lasting three months or more. The damage can be structural (detected through imaging or biopsy), indicated by markers like protein in the urine (proteinuria), or shown by a reduced glomerular filtration rate (GFR) — the primary measure of how well your kidneys are filtering blood. A normal GFR is above 90 mL/min. CKD is diagnosed when GFR drops below 60 or when there is evidence of kidney damage regardless of GFR.
The NIDDK notes that CKD typically progresses slowly over years, and the rate of progression varies enormously depending on the underlying cause, the severity at diagnosis, and how effectively risk factors are managed. Some people with CKD maintain stable kidney function for decades; others progress to kidney failure within years.
Stages of Chronic Kidney Disease
CKD is classified into five stages based on GFR, with higher stages indicating more severe kidney impairment:
- Stage 1 (GFR 90+): Normal or high GFR but with evidence of kidney damage (protein in urine, structural abnormalities). Kidneys function normally despite some damage.
- Stage 2 (GFR 60-89): Mildly decreased GFR with evidence of kidney damage. Still no symptoms in most cases.
- Stage 3a (GFR 45-59) and 3b (GFR 30-44): Moderately decreased kidney function. Complications like anemia and bone disease may begin. This is where most people are diagnosed.
- Stage 4 (GFR 15-29): Severely decreased function. Symptoms become more prominent. Preparation for dialysis or transplant should begin.
- Stage 5 (GFR below 15): Kidney failure (also called end-stage renal disease). Dialysis or a kidney transplant is needed to survive.
Knowing your stage is essential for guiding treatment intensity and planning. The National Kidney Foundation provides resources to help you understand what each stage means for your daily management and long-term outlook.
Causes and Risk Factors
Diabetes is the leading cause of CKD, responsible for roughly 44% of new kidney failure cases. High blood sugar damages the tiny blood vessels in the kidneys (glomeruli) over time — a condition called diabetic nephropathy. High blood pressure is the second leading cause, accounting for about 29% of cases. Elevated blood pressure damages kidney blood vessels, reducing their filtering capacity.
Other causes include glomerulonephritis (inflammation of the kidney’s filtering units), polycystic kidney disease (a genetic condition causing fluid-filled cysts), recurrent kidney infections, kidney stones causing obstruction, prolonged urinary tract obstruction (from enlarged prostate, for example), and autoimmune diseases like lupus. Certain medications — including long-term NSAID use — can damage the kidneys.
Risk factors beyond diabetes and hypertension include age over 60, family history of kidney disease, cardiovascular disease, obesity, smoking, and belonging to certain racial groups — African Americans, Hispanics, and Native Americans face disproportionately higher rates. According to the Mayo Clinic, having multiple risk factors multiplies your likelihood of developing CKD.
Symptoms
CKD earns its reputation as a “silent disease” because symptoms typically don’t appear until the kidneys have lost significant function — often 70% or more. In the early stages (1-3a), most people feel completely normal. As the disease progresses, symptoms develop gradually and can be vague enough to be attributed to other causes.
Common symptoms in advanced CKD include fatigue and weakness (from anemia and toxin buildup), swelling in the feet, ankles, and hands (from fluid retention), decreased urine output, foamy or bubbly urine (from excess protein), persistent itching, nausea and vomiting, loss of appetite, metallic taste in the mouth, difficulty concentrating, muscle cramps, and sleep problems.
Because symptoms are so nonspecific, the CDC recommends regular screening for people at risk — particularly those with diabetes, hypertension, or a family history of kidney disease. Simple blood and urine tests can detect CKD long before symptoms emerge.
Diagnosis and Monitoring
Two tests are central to CKD diagnosis and monitoring. A blood test for creatinine is used to calculate your estimated GFR (eGFR), which tells you how well your kidneys are filtering. A urine test for albumin (a type of protein) detects kidney damage — healthy kidneys keep albumin in the blood, and its presence in urine indicates the filtration system is leaking.
The albumin-to-creatinine ratio (ACR) from a spot urine sample is the preferred test for proteinuria. An ACR above 30 mg/g is abnormal. Higher levels of proteinuria are associated with faster CKD progression and higher cardiovascular risk. Both eGFR and ACR should be monitored regularly — together, they provide a comprehensive picture of kidney health.
Additional tests may include a complete metabolic panel (for electrolytes, calcium, phosphorus), complete blood count (for anemia), parathyroid hormone levels, lipid panel, and kidney ultrasound to evaluate size and structure. The NIDDK notes that kidney biopsy may be needed in some cases to determine the specific cause of CKD, particularly when the cause is unclear or when a treatable condition like glomerulonephritis is suspected.
Slowing CKD Progression
While kidney damage that has already occurred generally can’t be reversed, slowing progression is absolutely achievable — and in some cases, progression can be nearly halted. The two most important interventions are blood pressure control and blood sugar control in people with diabetes.
Blood pressure targets for CKD patients are typically below 130/80 mmHg. ACE inhibitors and ARBs are the preferred blood pressure medications because they provide additional kidney protection beyond blood pressure reduction — they reduce proteinuria and slow GFR decline. These medications are a cornerstone of CKD treatment regardless of blood pressure level, as long as they’re tolerated.
A landmark class of medications has emerged in CKD management: SGLT2 inhibitors (such as dapagliflozin and empagliflozin), originally developed for diabetes, have shown remarkable kidney-protective effects in people with CKD — even those without diabetes. The DAPA-CKD trial, published in the New England Journal of Medicine, showed a 39% reduction in the risk of kidney function decline, kidney failure, or kidney-related death. These drugs are now recommended by major guidelines for CKD with proteinuria. Understanding medication costs is important when planning long-term CKD treatment.
Diet and Lifestyle for CKD
Dietary management becomes increasingly important as CKD progresses. In early stages, a heart-healthy diet low in sodium (less than 2,300 mg daily) is the primary recommendation. As kidney function declines, additional restrictions may be needed for potassium, phosphorus, and protein.
Protein intake is a nuanced topic. Excess protein increases the workload on damaged kidneys, and moderate protein restriction (0.6-0.8 g/kg/day) is often recommended in stages 3-5 to slow progression. However, too little protein can lead to muscle wasting and malnutrition, particularly in older adults. A renal dietitian can help you find the right balance.
Staying well-hydrated (unless your doctor advises fluid restriction), maintaining a healthy weight, exercising regularly, quitting smoking, and avoiding nephrotoxic medications (including over-the-counter NSAIDs like ibuprofen and naproxen) are all important. The National Kidney Foundation offers detailed dietary guidance for each stage of CKD.
Complications of CKD
As kidney function declines, numerous complications can develop. Cardiovascular disease is the leading cause of death in people with CKD — far exceeding the risk of reaching kidney failure. Even mild CKD doubles your risk of heart disease and stroke. Aggressive management of blood pressure, cholesterol, and blood sugar is critical.
Anemia develops because damaged kidneys produce less erythropoietin, the hormone that stimulates red blood cell production. Treatment includes erythropoiesis-stimulating agents (ESAs) and iron supplementation. Bone disease (renal osteodystrophy) occurs because the kidneys can’t properly balance calcium, phosphorus, and vitamin D. Untreated, this leads to bone weakness and fractures.
Electrolyte imbalances — particularly elevated potassium (hyperkalemia) — can be dangerous. High potassium can cause life-threatening heart rhythm disturbances. Fluid overload leads to swelling, shortness of breath, and high blood pressure. Metabolic acidosis (excess acid in the blood) accelerates kidney decline and muscle wasting. Each of these complications requires specific monitoring and management.
Dialysis and Transplant
Dialysis
When kidneys can no longer sustain life — typically at stage 5, when GFR drops below 15 — renal replacement therapy is needed. Hemodialysis, the most common form, filters blood through a machine three times per week, each session lasting about four hours. It’s typically performed at a dialysis center, though home hemodialysis is an option for some. Peritoneal dialysis uses the lining of your abdomen as a filter and can be performed at home, daily or overnight, offering more flexibility.
Planning for dialysis should begin well in advance — ideally in stage 4. This includes surgical creation of a vascular access site (arteriovenous fistula, which takes weeks to mature), education about dialysis options, and discussions about whether transplant is possible. According to the NIDDK, early planning leads to better outcomes and smoother transitions.
Kidney Transplant
Kidney transplantation is the preferred treatment for kidney failure in eligible patients. A transplanted kidney provides better quality of life and longer survival than dialysis. Kidneys can come from deceased donors (average wait time is 3-5 years) or living donors (who can be family members, friends, or even altruistic strangers). Pre-emptive transplant — performed before dialysis is needed — produces the best outcomes.
After transplant, lifelong immunosuppressive medications are required to prevent rejection. These medications have side effects, including increased infection risk and higher rates of certain cancers, but for most people, the benefits of transplant far exceed the risks. More than 25,000 kidney transplants are performed annually in the United States.
Frequently Asked Questions
Can chronic kidney disease be reversed?
In most cases, CKD cannot be reversed because kidney damage from scarring is permanent. However, if the underlying cause is identified and treated early — such as removing an obstruction or controlling an autoimmune flare — some recovery of function is possible. More importantly, progression can be significantly slowed or even halted with proper treatment, keeping many people off dialysis for years or indefinitely.
How do I know if I have chronic kidney disease?
The only reliable way to know is through blood and urine tests — a blood test for eGFR and a urine test for albumin. Since CKD causes no symptoms until advanced stages, regular screening is essential if you have risk factors. Ask your doctor about kidney function testing, particularly if you have diabetes, hypertension, or a family history of kidney disease.
Is chronic kidney disease hereditary?
Some forms of CKD have a strong genetic component. Polycystic kidney disease is inherited. Having a family history of kidney disease increases your risk, even for non-genetic forms — partly because conditions like diabetes and hypertension that cause CKD also run in families. If kidney disease runs in your family, earlier and more frequent screening is warranted.
Can I take over-the-counter pain relievers with CKD?
NSAIDs (ibuprofen, naproxen, aspirin at anti-inflammatory doses) should generally be avoided with CKD, as they can worsen kidney function and cause acute kidney injury. Acetaminophen (Tylenol) is generally safer for the kidneys but should be used at the lowest effective dose. Always consult your doctor before taking any over-the-counter medication.
How long can you live with chronic kidney disease?
Life expectancy with CKD depends heavily on the stage at diagnosis, underlying cause, age, and how well comorbid conditions (especially cardiovascular risk factors) are managed. Many people with stage 1-3 CKD live normal or near-normal lifespans. Even with kidney failure requiring dialysis, people can live for years or decades, and kidney transplant recipients often have life expectancy approaching that of the general population.
What You Can Do Right Now
If you have CKD, the most impactful things you can do are take your blood pressure medications consistently (especially ACE inhibitors or ARBs), manage your blood sugar if you have diabetes, follow dietary recommendations, stay physically active, avoid nephrotoxic substances, and keep all follow-up appointments so your kidney function can be tracked over time.
If you’re at risk but haven’t been tested, ask your doctor for a kidney function check at your next visit. Two simple tests — blood and urine — can detect CKD long before it causes problems. Early detection gives you the widest window of opportunity to slow or stop progression. The kidneys you have are the only ones you’ll get (unless you’re fortunate enough to receive a transplant), and protecting them is worth the effort.