What glomerular filtration rate range indicates stage 4 chronic kidney disease?

Stage 4 chronic kidney disease (CKD) is characterized by a significantly decreased glomerular filtration rate (GFR). A GFR range of 15-29 mL/min indicates that the kidneys are severely impaired in their ability to filter waste products from the blood effectively. During this stage, the risk for complications of kidney disease increases, necessitating careful management and preparation for potential dialysis or kidney transplantation.

In the context of CKD staging, a GFR of 60-89 mL/min represents stage 2, while 30-59 mL/min signifies stage 3. A GFR above 90 mL/min is considered normal or indicative of stage 1 CKD. Therefore, the clear demarcation for stage 4 is found in the significantly lower range of 15-29 mL/min, emphasizing the critical nature of renal function impairment at this stage.