Normal GFR for a 36-Year-Old Male
The normal glomerular filtration rate (GFR) for a 36-year-old male is approximately 130 mL/min/1.73 m² 1.
Understanding Normal GFR Values
Normal GFR varies by age, sex, and body size. For adult males, the reference ranges are:
- Young adult males (20-40 years): 120-130 mL/min/1.73 m² 1
- Young adult females (20-40 years): 90-120 mL/min/1.73 m² 1
GFR naturally declines with age at an average rate of:
- Approximately 0.75-0.8 mL/min/year after age 40 1, 2
- Before age 40, GFR typically remains relatively stable 3
Measurement and Estimation Methods
GFR is most commonly estimated using prediction equations rather than directly measured:
- MDRD Study Equation: More accurate for GFR <90 mL/min/1.73 m² 1
- CKD-EPI Equation: More accurate for GFR >60 mL/min/1.73 m² and better predicts adverse outcomes 1
- Cockcroft-Gault Equation: Commonly used but less accurate than newer formulas 1
Important Considerations
Serum creatinine alone is an unreliable indicator of kidney function 1, 4
- GFR must decline to approximately half the normal level before serum creatinine rises above the upper limit of normal
- In elderly patients, serum creatinine may remain normal despite significant GFR reduction due to decreased muscle mass
For a 36-year-old male, a GFR below 60 mL/min/1.73 m² would be considered abnormal and indicative of chronic kidney disease 1
Recent Research on Normal GFR Values
Recent studies have challenged traditional GFR reference values:
The Full Age Spectrum (FAS) equation suggests a mean GFR of approximately 107 mL/min/1.73 m² in healthy adults up to age 40, rather than the traditionally cited 120-130 mL/min/1.73 m² 3
A study of healthy potential kidney donors found median GFR values of 85 mL/min/1.73 m² in 30-34 year old men 2
However, the most authoritative guidelines from the National Kidney Foundation and American Society of Clinical Oncology still reference the 120-130 mL/min/1.73 m² range for young adult males 1.
Clinical Implications
- A GFR <60 mL/min/1.73 m² in a 36-year-old male represents loss of half or more of normal kidney function and would be classified as chronic kidney disease 1
- Below this threshold, the prevalence of complications increases significantly
- Medication dosing may need adjustment when GFR falls below normal ranges
For a 36-year-old male with no kidney disease, the expected normal GFR would be in the range of 120-130 mL/min/1.73 m², though individual variation exists.