Creatinine clearance values are typically interpreted as follows:
This Creatinine Clearance Calculator, utilizing the Cockcroft-Gault formula, is a tool primarily intended for healthcare professionals. It is commonly used in various clinical settings to:
It's important to note that while the Cockcroft-Gault formula is historically significant, newer formulas like the MDRD (Modification of Diet in Renal Disease) study equation and the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation are often preferred for GFR estimation in many clinical guidelines. The choice of formula can depend on the specific patient population and clinical context.
The Cockcroft-Gault formula estimates creatinine clearance as a clinical approximation of glomerular filtration rate (GFR). However, creatinine clearance may overestimate GFR by 10-20% and has been replaced in clinical practice by formulas that estimate GFR more directly.
Additionally, the Cockcroft-Gault formula uses weight, which may be less accurate at weight extremes (underweight and especially overweight/obese). Adjustments and estimations are recommended as follows, according to Brown et al. and Winter et al.:
| Category | BMI | Calculation |
|---|---|---|
| Underweight | BMI <18.5 | Calculate using actual/total body weight (i.e., no adjustment) |
| Normal weight | BMI 18.5-24.9 | Calculate using ideal body weight, range using actual weight |
| Overweight/Obese | BMI ≥25 | Calculate using adjusted body weight, range using ideal body weight |
Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron. 1976;16(1):31-41. PubMed PMID: 1244564.
Creatinine clearance is an important indicator for assessing kidney function. It estimates how effectively your kidneys can filter creatinine from the blood.
The Cockcroft-Gault formula uses age, weight, gender, and serum creatinine levels to estimate creatinine clearance, while other methods may use different parameters.
The results show your creatinine clearance rate, usually in milliliters per minute (ml/min). Lower values may indicate decreased kidney function.
While the Cockcroft-Gault formula is widely used, it may not be as accurate as other methods in certain situations, especially at weight extremes.
Choose the appropriate weight type based on your BMI. Use actual weight for underweight, ideal weight for normal weight, and adjusted weight for overweight/obese.
This calculator is primarily designed for adults; assessing creatinine clearance in children may require different methods.
Creatinine clearance is a vital measure because it reflects how well the kidneys are filtering waste products from the blood. It helps in diagnosing kidney dysfunction, monitoring the progression of kidney disease, and adjusting dosages of medications that are eliminated by the kidneys.
Several factors can influence creatinine clearance levels, including age (it naturally declines with age), sex (males generally have higher muscle mass and thus higher creatinine production), muscle mass (more muscle leads to more creatinine), diet (high protein intake can temporarily increase it), certain medications, and underlying health conditions like dehydration or heart failure.
No, while the Cockcroft-Gault formula is a well-known method, other equations like the MDRD (Modification of Diet in Renal Disease) study equation and the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation are also commonly used, and often preferred, to estimate glomerular filtration rate (eGFR). These newer equations are generally considered more accurate in various populations.
A "normal" creatinine clearance value typically indicates that the kidneys are functioning adequately in filtering creatinine. For adults, this is generally considered to be ≥90 mL/min. However, what's "normal" can vary slightly based on the laboratory and individual factors. It's always best to discuss your results with a healthcare provider.
Lifestyle changes can support overall kidney health, which may indirectly benefit creatinine clearance. These include staying well-hydrated, maintaining a healthy blood pressure, managing blood sugar if diabetic, eating a balanced diet moderate in protein, avoiding excessive use of NSAIDs, and not smoking. However, specific improvements in creatinine clearance often depend on addressing the underlying cause of any kidney dysfunction.
The frequency of checking creatinine clearance depends on individual health status, risk factors for kidney disease, and whether any kidney conditions are already present. Individuals with known kidney disease, diabetes, hypertension, or a family history of kidney problems may need more frequent monitoring as recommended by their doctor.
This calculator is provided for educational and informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.
The results from this calculator should be interpreted by healthcare professionals in the context of the patient's overall clinical picture. Decisions about patient care should not be based solely on the results of this calculator.