Written by: Emmanuel Dubure, MPhil & Kristen DiFilippo, PhD, RDN
Think of your kidneys as the bouncers at the trendiest club in your body. They decide who gets to stay in (the good stuff) and who gets kicked out (the waste). But if the bouncers stop doing their job, things go awry.
Chronic Kidney Disease (CKD) is a progressive condition in which the kidneys lose their ability to function properly over time (Pan American Health Organization, 2022). CKD affects over 800 million people globally (Kovesdy, 2022), and in the United States, nearly 36 million people have CKD (Centers for Disease Control and Prevention [CDC], 2023).The kidneys remove waste substances from the body and perform other important functions, including controlling blood pressure and helping the body make red blood cells (Raghavendra et al., 2013). These functions can be impaired when a person has CKD. CKD can lead to serious complications, including cardiovascular disease, kidney failure, anemia, weakened bones, fluid retention, and the buildup of harmful substances in the blood (Bello et al., 2017). While CKD is a serious medical condition, early diagnosis and proper management can help slow its progression and improve prognosis and overall health.
Risk factors for CKD
Risk factors for CKD include uncontrolled diabetes, hypertension, and advancing age. Other factors include smoking, obesity, a family history of CKD, and being Black/African American. Excessive use of certain medications, autoimmune conditions, and some infections may also affect the kidneys (Evans & Taal, 2015).
Signs and symptoms of CKD
The initial stages of CKD may show no visible signs (Chen et al., 2019). However, some later signs may include tiredness, itchy skin, puffiness, swollen limbs, muscle cramps, and changes in urine output and appearance (National Kidney Foundation, 2024).
Diagnosis of CKD
CKD is diagnosed when the glomerular filtration rate (GFR), a marker of kidney function, declines to less than 60.
Stages of CKD
There are five stages of CKD (Chen et al., 2019). These are classified based on the extent of decline of kidney function.
- Stage 1: A normal GFR of ≥ 90 mL/min, but with other signs of kidney abnormality, such as high protein in the urine
- Stage 2: A mild decrease in kidney function and a GFR of 60–89 mL/min with other signs of kidney abnormality
- Stage 3a: A moderate decline in kidney function with a GFR of 45–59 mL/min
- Stage 3b: A moderate decline in kidney function with a GFR of 30–44 mL/min
- Stage 4: A severe decline in kidney function with a GFR of 15–29 mL/min
- Stage 5: Also known as end-stage kidney disease and characterized by a GFR of <15 mL/min
Management of CKD
CKD is managed using dietary modification, medication and, when necessary, dialysis.
- Dietary changes: People with CKD will need a special diet to reduce the buildup of waste in the body. Protein, sodium, potassium, and phosphorus intake is often controlled with the help of a dietitian (Kalantar-Zadeh & Fouque, 2017). Fluids may also be restricted depending on the patient’s condition (Lambert et al., 2022).
- Medication: Medication may be used to treat comorbidities such as diabetes and heart disease (Li et al., 2023).
- Dialysis: End-stage kidney disease is managed with dialysis, a procedure to artificially remove waste from the blood (Himmelfarb et al., 2020). Some patients may also need a kidney transplant (Hariharan et al., 2021).
Prevention of CKD
In many cases, CKD can be prevented by managing pre-existing medical conditions and risk factors for the disease. It is recommended to maintain a healthy weight, avoid smoking and eat a diet low in sodium, saturated fats and trans fats (National Institute of Diabetes and Digestive and Kidney Diseases, 2024).
CKD is a major public health problem associated with serious adverse health outcomes. Reducing its burden requires preventive measures, including good nutrition and healthy lifestyle choices, early diagnosis, and timely treatment to slow the progression of the disease and improve patients’ quality of life.
Are you at risk for CKD? Talk to your doctor about getting your kidney function checked. For more information and resources, visit the National Kidney Foundation website: https://www.kidney.org/kidney-topics/chronic-kidney-disease-ckd
References
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Centers for Disease Control and Prevention. (2023). Chronic Kidney Disease in the United States, 2023. https://www.cdc.gov/kidneydisease/publications-resources/ckd-national-facts.html
Chen, T. K., Knicely, D. H., & Grams, M. E. (2019). Chronic kidney disease diagnosis and management: A review. JAMA, 322(13), 1294–1304. https://doi.org/10.1001/jama.2019.14745
Damtie, S., Biadgo, B., Baynes, H. W., Ambachew, S., Melak, T., Asmelash, D., & Abebe, M. (2018). Chronic kidney disease and associated risk factors assessment among diabetes mellitus patients at a tertiary hospital, Northwest Ethiopia. Ethiopian Journal of Health Sciences, 28(6), 691–700. https://doi.org/10.4314/ejhs.v28i6.3
Evans, P. D., & Taal, M. W. (2015). Epidemiology and causes of chronic kidney disease. Medicine (United Kingdom), 43(8), 450–453. https://doi.org/10.1016/j.mpmed.2015.05.005
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Kalantar-Zadeh, K., & Fouque, D. (2017). Nutritional management of chronic kidney disease. New England Journal of Medicine, 377(18), 1765–1776. https://doi.org/10.1056/NEJMra1700312
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Kovesdy, C. P. (2022). Epidemiology of chronic kidney disease: An update 2022. Kidney International Supplements, 12(1), 7–11. https://doi.org/10.1016/j.kisu.2021.11.003
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Li, Y., Barve, K., Cockrell, M., Agarwal, A., Casebeer, A., Dixon, S. W., & Poonawalla, I. (2023). Managing comorbidities in chronic kidney disease reduces utilization and costs. BMC Health Services Research, 23(1), 1418. https://doi.org/10.1186/s12913-023-10424-8
National Institute of Diabetes and Digestive and Kidney Diseases. (2024). Preventing Chronic Kidney Disease. https://www.niddk.nih.gov/health-information/kidney-disease/chronic-kidney-disease-ckd/prevention
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