Intraindividual variability in Hb levels dependent on ESA usage, defined by residual SD of Hb, intraindividual change in Hb in consecutive measurements, Hb amplitude, and Hb category
| Hb Variability Definitions | No ESA Use (n = 3143) | On ESA Throughout (n = 1823) | Commenced ESA (n = 1199) | P |
|---|---|---|---|---|
| Hb intercept (g/L; mean ± SD) | 124.9 ± 15.3 | 112.6 ± 15.4 | 103.1 ± 11.8 | <0.0001 |
| Hb slope (g/L per mo; mean ± SD) | −0.1 ± 2.6 | 1.4 ± 4.1 | 2.7 ± 4.0 | <0.0001 |
| Residual SD (g/L; mean ± SD) | 4.9 ± 4.4 | 6.8 ± 4.8 | 7.3 ± 4.9 | <0.0001 |
| Intraindividual change in Hb (g/L; mean ± SD) | 6.6 ± 5.3 | 8.6 ± 5.5 | 9.7 ± 5.6 | <0.0001 |
| SD of intraindividual change in Hb (g/L; mean ± SD) | 8.0 ± 7.4 | 10.0 ± 7.2 | 11.1 ± 7.5 | <0.0001 |
| Hb change (%) | ||||
| all consecutive Hb change ≤5 g/L | 25.1 | 7.4 | 4.7 | <0.0001 |
| consecutive Hb decrease >5 g/L | 19.9 | 31.0 | 38.8 | |
| consecutive Hb increase >5 g/L | 24.1 | 11.8 | 7.3 | |
| both consecutive Hb decrease and increase >5 g/L | 30.9 | 49.8 | 49.2 | |
| Hb amplitude (g/L; %) | ||||
| 0 to 10 | 50.0 | 18.2 | 12.9 | <0.0001 |
| 11 to 20 | 33.7 | 37.0 | 33.3 | |
| >20 | 16.3 | 44.8 | 53.8 | |
| Classification of Hb variability (%) | <0.0001 | |||
| group I (Hb >130 g/L) | 22.8 | 2.9 | 0.3 | |
| group II (Hb >130 and 110 to 130 g/L) | 24.1 | 22.3 | 4.6 | |
| group III (Hb 110 to 130 g/L) | 24.6 | 12.8 | 5.1 | |
| group IV (Hb 110 to 130 and <110 g/L) | 18.4 | 33.9 | 49.6 | |
| group V (Hb <110 g/L) | 5.4 | 11.1 | 17.3 | |
| group VI (Hb >130 and 110 to 130 and <110 g/L) | 4.7 | 17.0 | 23.1 |