Question 1

What's the difference between GFR and eGFR?

Accepted Answer

GFR refers to the actual glomerular filtration rate, while eGFR is the estimated version calculated from blood creatinine levels, age, and sex. The 'e' stands for estimated because measuring true GFR directly requires complex procedures that aren't practical for routine testing. eGFR provides an excellent approximation of kidney function for most people and is the standard test used in clinical practice.

Question 2

Can dehydration affect my eGFR results?

Accepted Answer

Yes, hydration status can significantly impact eGFR results. Dehydration can make results appear worse than they actually are, while being overly hydrated might make results appear better. For the most accurate results, maintain normal hydration levels before testing - avoid both excessive fluid intake and dehydration. This is why consistent testing conditions are important for tracking kidney function over time.

Question 3

How often should I have my eGFR tested?

Accepted Answer

Testing frequency depends on individual risk factors and current kidney function. People with diabetes, high blood pressure, or family history of kidney disease may benefit from annual testing. Those with known kidney disease may need more frequent monitoring every 3-6 months. Healthy individuals without risk factors might test every few years as part of routine health screening. Your healthcare provider can recommend an appropriate testing schedule based on your specific situation.

Question 4

Is it normal for eGFR to decline with age?

Accepted Answer

Yes, eGFR naturally declines with age even in healthy individuals due to normal physiological changes in the kidneys. The rate of decline varies, but generally, kidney function decreases by about 1 mL/min/1.73 m² per year after age 30-40. Values that might indicate kidney disease in younger adults could be normal for someone over 70. This is why age-adjusted interpretation of results is important.

Question 5

What medications can affect eGFR results?

Accepted Answer

Several medications can influence eGFR results, including certain blood pressure medications (ACE inhibitors, ARBs), some antibiotics, NSAIDs (ibuprofen, naproxen), and diuretics. Some medications may temporarily reduce eGFR without causing permanent kidney damage, while others might have protective effects. It's important to inform your healthcare provider about all medications you're taking when interpreting results, as dosage adjustments may be needed based on kidney function.

Question 6

Can I improve my eGFR naturally?

Accepted Answer

While you cannot reverse significant kidney damage, certain lifestyle measures may help maintain or slightly improve kidney function. These include staying well-hydrated, maintaining healthy blood pressure, managing diabetes effectively, following a kidney-friendly diet with appropriate protein intake, exercising regularly, avoiding smoking, and limiting NSAIDs use. However, the effectiveness of these measures depends on the underlying cause of reduced eGFR and individual circumstances.

GFR (Glomerular Filtration Rate)