Chronic kidney disease (CKD) is a long-term condition in which the kidneys become damaged or lose some of their ability to filter the blood properly. Because the kidneys help remove waste and extra fluid from the body, reduced kidney function can affect many parts of the body over time.
CKD often develops gradually and may cause few or no noticeable symptoms in its early stages. This is one reason why people with important risk factors, especially diabetes and high blood pressure, may need regular kidney testing. Early detection can allow healthcare professionals to identify the cause, manage risk factors, and take steps that may slow further kidney damage.
According to the World Health Organization, an estimated 674 million people worldwide have chronic kidney disease, with most affected people living in low- and middle-income countries. Severe kidney disease can progress to kidney failure, which may require dialysis or a kidney transplant to sustain life.
This article explains what chronic kidney disease is, its causes and risk factors, symptoms, stages, diagnosis, treatment, prevention, possible complications, and when medical attention may be needed.
What Is Chronic Kidney Disease?
The kidneys are two organs located toward the back of the abdomen. They continuously filter the blood and help remove waste products and excess fluid through urine.
They also play important roles in maintaining fluid and electrolyte balance and supporting other body functions.
Chronic kidney disease means there is an abnormality in kidney structure or function that persists over time. CKD can develop because of diseases that damage the kidney’s filtering system, blood vessels, or other kidney tissues.
Unlike acute kidney injury, which can happen suddenly, CKD usually develops gradually. Some forms of kidney damage may be permanent, although appropriate treatment can often slow progression and reduce complications.
Not everyone with CKD will develop kidney failure. The risk depends on factors such as the underlying cause, kidney function, urine albumin levels, other health conditions, and how effectively the condition is managed.
What Do the Kidneys Do?
Healthy kidneys perform several important functions, including:
- Filtering waste products from the blood
- Removing excess fluid through urine
- Helping maintain the body’s fluid and electrolyte balance
- Supporting blood pressure regulation
- Helping maintain healthy bones and blood chemistry
- Producing hormones involved in important body functions
When kidney function decreases, waste and excess fluid can build up in the body. Advanced CKD can also contribute to problems such as anemia, mineral and bone disorders, electrolyte abnormalities, and cardiovascular disease.
What Causes Chronic Kidney Disease?
The two most common causes of CKD in adults are diabetes and high blood pressure.
Diabetes
Persistently high blood glucose can damage the small blood vessels and filtering structures inside the kidneys. Over time, this damage can reduce the kidneys’ ability to filter waste and excess fluid.
Kidney disease caused by diabetes is often called diabetic kidney disease.
People with diabetes may therefore need regular testing of kidney function and urine albumin, even when they do not have kidney-related symptoms.
High Blood Pressure
High blood pressure can damage blood vessels throughout the body, including those in the kidneys.
Kidney damage can then make it harder for the kidneys to regulate fluid and blood pressure, creating a cycle in which kidney disease and high blood pressure can worsen one another.
Other Causes
Other possible causes of CKD include:
- Glomerular diseases
- Polycystic kidney disease
- Certain inherited conditions
- Repeated or severe kidney infections
- Complications of acute kidney injury
- Certain autoimmune diseases
- Kidney or urinary tract abnormalities
- Some medicines or substances that can damage the kidneys
- Kidney stones when they cause significant complications
- Certain cardiovascular or liver-related conditions
The cause of CKD matters because identifying it can help healthcare professionals select an appropriate management plan.
Risk Factors for Chronic Kidney Disease
Some people have a greater chance of developing CKD.
Important risk factors include:
- Diabetes
- High blood pressure
- Heart disease
- Family history of kidney disease or kidney failure
- Overweight or obesity
- Older age
- Certain genetic conditions
- Previous kidney injury
- Some inflammatory or autoimmune conditions
The CDC notes that diabetes, high blood pressure, heart disease, family history, and obesity are important CKD risk factors.
Having a risk factor does not necessarily mean that someone will develop CKD. However, it can make appropriate monitoring and preventive care more important.
Chronic Kidney Disease and Diabetes
Diabetes and kidney disease are closely connected.
High blood sugar over time can damage the kidney’s small blood vessels and filtering structures. Kidney disease may develop gradually without obvious symptoms.
Regular testing can help identify kidney damage before significant symptoms appear. People with diabetes should discuss kidney testing with their healthcare professional and follow the recommended testing schedule.
Chronic Kidney Disease and High Blood Pressure
High blood pressure is both a major cause and a possible consequence of CKD.
When blood pressure remains high for a long period, it can damage blood vessels in the kidneys. As kidney function decreases, the body may retain more sodium and fluid, which can contribute to higher blood pressure.
Managing blood pressure is therefore an important part of protecting kidney function.
Symptoms of Chronic Kidney Disease
One of the most important things to understand about CKD is that early kidney disease often causes no symptoms.
A person may have kidney damage while feeling completely well. This is why blood and urine testing can be important for people who have risk factors.
As kidney disease becomes more advanced, possible symptoms may include:
- Swelling in the legs, feet, ankles, hands, or face
- Tiredness
- Changes in urination
- Foamy urine
- Loss of appetite
- Nausea or vomiting
- Itching or dry skin
- Muscle cramps
- Difficulty concentrating
- Sleep problems
- Unintentional weight loss
- Shortness of breath
These symptoms are not specific to CKD and can occur with many other conditions. A person should not assume that symptoms alone confirm kidney disease.
Why Early Kidney Disease Can Be Difficult to Detect
Many people expect kidney disease to cause pain or obvious urinary symptoms.
However, CKD can develop silently.
This means that waiting for symptoms is not always a reliable way to identify kidney problems. Testing is particularly important for people with conditions such as diabetes or high blood pressure.
How Is Chronic Kidney Disease Diagnosed?
Healthcare professionals commonly use blood and urine tests to evaluate kidney health.
Two important markers are:
Estimated Glomerular Filtration Rate (eGFR)
A blood test measures creatinine, a waste product that the kidneys normally remove from the blood. Creatinine results can be used to estimate how efficiently the kidneys filter blood.
This estimated filtration rate is called eGFR.
A persistently reduced eGFR can indicate reduced kidney function. An eGFR below 60 mL/min/1.73 m² may indicate kidney disease, while an eGFR of 15 or lower is generally considered kidney failure. Interpretation depends on the complete clinical picture and repeat testing.
Urine Albumin
Healthy kidneys generally prevent significant amounts of albumin, a blood protein, from passing into urine.
When kidney filters are damaged, albumin can leak into the urine.
A urine albumin-to-creatinine ratio (UACR) is one test used to assess albumin in urine. NIDDK notes that a UACR above 30 mg/g may indicate kidney disease, although healthcare professionals interpret results in context and may repeat testing to confirm abnormal findings.
CKD Stages
CKD is commonly classified according to kidney function and other measures of kidney damage.
The eGFR categories commonly used are:
| Stage | eGFR | General description |
|---|---|---|
| G1 | 90 or higher | Normal or high kidney function, but kidney damage may be present |
| G2 | 60–89 | Mildly decreased |
| G3a | 45–59 | Mild to moderately decreased |
| G3b | 30–44 | Moderately to severely decreased |
| G4 | 15–29 | Severely decreased |
| G5 | Below 15 | Kidney failure |
An eGFR value alone does not tell the complete story. Doctors also consider urine albumin, the cause of kidney disease, other health conditions, and whether abnormalities persist over time. CKD is generally considered when kidney damage or reduced kidney function is present for more than three months.
What Happens as CKD Progresses?
CKD can remain stable for a long period, progress slowly, or worsen more quickly depending on the underlying cause and other factors.
Progression may increase the risk of:
- Kidney failure
- Cardiovascular disease
- High blood pressure
- Anemia
- Electrolyte abnormalities
- Mineral and bone disorders
- Nutritional problems
However, progression is not inevitable for every person with CKD. Treatment and management of underlying causes can help protect remaining kidney function.
Treatment of Chronic Kidney Disease
There is no single treatment that works for every person with CKD.
Treatment depends on the cause, stage of kidney disease, urine albumin levels, blood pressure, diabetes status, other medical conditions, and individual circumstances.
The goals generally include:
- Treating the underlying cause
- Controlling blood pressure
- Managing blood glucose when diabetes is present
- Reducing cardiovascular risk
- Monitoring kidney function
- Managing complications
- Slowing progression toward kidney failure
Healthcare professionals may use medicines, nutrition changes, physical activity recommendations, and other approaches as appropriate.
Controlling Blood Pressure
Blood pressure management is particularly important for people with CKD.
High blood pressure can contribute to further kidney damage, while kidney disease can make blood pressure more difficult to control.
Depending on the person’s condition, healthcare professionals may prescribe medicines that lower blood pressure and may provide specific dietary and lifestyle recommendations.
People with CKD should not change or stop blood pressure medicines without discussing it with their healthcare professional.
Managing Diabetes
For people with diabetes, maintaining appropriate blood glucose control can help reduce the risk of diabetes-related complications, including kidney damage.
Diabetes treatment may include nutrition changes, physical activity, glucose monitoring, and medicines prescribed according to the individual’s needs.
People with both diabetes and CKD may require a coordinated treatment plan.
Nutrition and Kidney Health
Nutrition needs can change as CKD progresses.
Depending on kidney function and laboratory results, healthcare professionals may recommend paying attention to nutrients such as sodium, potassium, phosphorus, protein, or fluid intake.
There is no single kidney diet suitable for everyone.
A person with CKD should therefore avoid following highly restrictive diets without professional advice. A doctor or registered dietitian can help create an eating plan appropriate for kidney function and other health conditions.
Healthy eating patterns can also support blood pressure, blood glucose, weight, and cardiovascular health.
Physical Activity and Healthy Weight
Regular physical activity can support overall health and help manage important CKD risk factors such as high blood pressure, diabetes, and excess weight.
The appropriate type and amount of activity depends on a person’s health and kidney disease stage.
People with significant kidney disease or other medical conditions should discuss an appropriate exercise plan with their healthcare professional.
Maintaining a healthy weight may also reduce the risk associated with diabetes and high blood pressure, two major causes of CKD.
Avoiding Kidney-Harming Medicines and Substances
Some medicines can affect kidney function, particularly when used incorrectly, at high doses, or in people who already have kidney disease.
People with CKD should tell healthcare professionals and pharmacists about all prescription medicines, over-the-counter products, and supplements they use.
Do not stop prescribed medicines without medical advice.
It is also important to avoid assuming that a product marketed as “natural” is automatically safe for the kidneys.
Complications of Chronic Kidney Disease
Advanced CKD can affect many parts of the body.
Possible complications include:
Cardiovascular Disease
CKD is associated with an increased risk of heart and blood vessel disease, including heart attack and stroke.
Anemia
Reduced kidney function can contribute to anemia, which may cause tiredness and weakness.
Mineral and Bone Problems
Changes in kidney function can disturb calcium, phosphorus, vitamin D, and other processes involved in maintaining healthy bones.
Electrolyte Problems
Advanced kidney disease can affect electrolyte levels, including potassium.
Fluid Buildup
Reduced kidney function can cause the body to retain extra fluid, potentially leading to swelling and, in severe cases, breathing problems.
Kidney Failure
Some people with advanced CKD eventually develop kidney failure. When the kidneys can no longer adequately perform their essential functions, kidney replacement treatment such as dialysis or kidney transplantation may be required.
Can Chronic Kidney Disease Be Prevented?
Not every case of CKD can be prevented, particularly when genetic or unavoidable medical conditions are involved.
However, many important risk factors can be managed.
Helpful measures include:
- Managing diabetes
- Controlling high blood pressure
- Maintaining a healthy weight
- Being physically active
- Following a balanced eating pattern
- Avoiding tobacco
- Taking medicines as prescribed
- Avoiding unnecessary kidney-harming medicines or substances
- Getting appropriate kidney testing when at risk
- Managing heart disease and other chronic conditions
The CDC emphasizes that managing diabetes and high blood pressure can help prevent or delay CKD.
Who Should Consider Kidney Testing?
People with certain risk factors should discuss kidney testing with a healthcare professional.
This includes people with:
- Diabetes
- High blood pressure
- Heart disease
- A family history of kidney failure
- Other conditions associated with kidney disease
For people with diabetes, regular kidney testing is particularly important because early kidney disease may not cause symptoms.
When Should You Seek Medical Attention?
A person with known or suspected kidney disease should seek medical advice if they develop concerning symptoms such as significant swelling, major changes in urination, persistent nausea or vomiting, severe weakness, shortness of breath, or other new or worsening symptoms.
People with severe symptoms, especially difficulty breathing, chest pain, confusion, fainting, or a major deterioration in their condition, should seek urgent medical care.
The appropriate response depends on the person’s symptoms and overall medical condition.
Frequently Asked Questions
Can kidney disease have no symptoms?
Yes. Early CKD often causes no noticeable symptoms. Blood and urine tests may detect kidney problems before a person feels unwell.
What are the two main causes of CKD?
Diabetes and high blood pressure are the two most common causes of CKD in adults.
Can chronic kidney disease be cured?
Some causes of kidney disease can be treated effectively, but established chronic kidney damage may not be completely reversible. Treatment can often slow progression and reduce complications.
Is CKD the same as kidney failure?
No. CKD describes a broad range of long-term kidney damage or reduced kidney function. Kidney failure represents the most severe stage of kidney disease.
Can people with CKD live normal lives?
Many people with CKD live for years while managing their condition. The outlook varies according to the cause, stage, other health conditions, and response to treatment.
Should people with diabetes get kidney tests?
Yes. Diabetes is a major risk factor for CKD, and regular testing can help detect kidney problems early.
What tests are commonly used for CKD?
Blood testing for creatinine and estimated GFR, together with urine testing for albumin, are important tools for detecting and monitoring CKD.
Conclusion
Chronic kidney disease is a long-term condition that can develop gradually and remain unnoticed during its early stages. Diabetes and high blood pressure are major causes, making good control of these conditions an important part of kidney protection.
Because early CKD often has few or no symptoms, appropriate testing can be more useful than waiting for warning signs. Blood tests such as creatinine and eGFR and urine tests for albumin can help healthcare professionals identify kidney problems and monitor changes over time.
Treatment focuses on identifying the cause, controlling risk factors, protecting remaining kidney function, and managing complications. Healthy eating, physical activity, appropriate weight management, blood pressure control, diabetes management, and regular medical follow-up can all contribute to better kidney health.
If you have diabetes, high blood pressure, heart disease, a family history of kidney disease, or another risk factor, discuss kidney testing with a qualified healthcare professional.
Medical Disclaimer
This article is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Kidney disease can vary significantly from person to person. Always consult a qualified healthcare professional for diagnosis, test interpretation, medication decisions, and individualized treatment.
Sources & References
- World Health Organization (WHO) — Kidney Disease.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) — Chronic Kidney Disease.
- NIDDK — Chronic Kidney Disease Tests & Diagnosis.
- NIDDK — Causes of Chronic Kidney Disease in Adults.
- Centers for Disease Control and Prevention (CDC) — Risk Factors for Chronic Kidney Disease.
- CDC — Preventing Chronic Kidney Disease.
- NIDDK — Identify & Evaluate Patients with Chronic Kidney Disease.
- NIDDK — What Is Chronic Kidney Disease in Adults?