What is the defining GFR level for chronic kidney disease (CKD)?

The defining level of glomerular filtration rate (GFR) for chronic kidney disease (CKD) is below 60 mL/min/1.73 m². This threshold is established based on the recognition that GFR values below this level are indicative of significant kidney impairment. CKD is characterized by a decline in kidney function that persists for at least three months, and a GFR below 60 suggests that the kidneys are not filtering waste effectively, leading to the accumulation of toxins in the body.

Additionally, the classification of CKD incorporates various stages based on GFR levels, with stage 3 CKD beginning at a GFR of less than 60, reinforcing the importance of this cutoff in diagnosis and management. Early identification at this stage is crucial for implementing interventions to slow disease progression, manage complications, and optimize patient outcomes.

In contrast, GFR values above 60, while indicating some level of kidney function, do not meet the criteria for CKD diagnosis. This is why levels below 90 or 75 do not define the disease, as they can still be seen in individuals with normal or only mildly impaired kidney function. Similarly, while a GFR below 45 indicates more severe kidney dysfunction, it falls into a more