| Stage | Kidney function | Clcr (ml/min/1.73m2) |
| 1 | Kidney damage (microalbuminuria, proteinuria), preserved function, with risk factors | >90 |
| 2 | Kidney damage with low renal insufficiency | 60 - 89 |
| 3 | Kidney damage with moderate renal insufficiency | 30 - 59 |
| 4 | Kidney damage with severe renal insufficiency | 15 - 29 |
| 5 | Kidney damage with terminal renal insufficiency or dialysis | <15 |