Table 2.
Serum concentrations of vitamin D metabolites, albumin, and vitamin D-binding protein (DBP) according to:
| a) chronic kidney disease (CKD) stage | ||||
|---|---|---|---|---|
| CKD 2/3 n = 60 | CKD 4/5 n = 43 | Dialysis n = 45 | p1 | |
| Total 25(OH)D (ng/ml) | 30.6 (18.9, 35.7) | 22.0 (11.4, 31.9) | 14.1 (8.3, 19.4) | <0.001 |
| Free 25(OH)D (pg/ml) | 10.3 (7.0, 14.4) | 8.2 (5.2, 11.6) | 5.2 (3.8, 8.1) | <0.001 |
| Bioavailable 25(OH)D (ng/ml) | 3.6 (2.5, 5.2) | 2.7 (1.8, 3.7) | 1.6 (0.9, 2.3) | <0.001 |
| Albumin (g/dl) | 4.1 (3.8, 4.3) | 4.0 (3.5, 4.2) | 3.4 (3.0, 3.7) | <0.001 |
| DBP (mg/dl) | 20.2 (14.0, 27.9) | 20.8 (11.2, 28.8) | 19.5 (11.1, 28.2) | >0.6 |
| 1,25(OH)2D (pg/ml) | 37.0 29.2, 45.2 | 32.9 22.4, 39.7 | 16.7 11.3, 22.3 | <0.001 |
| 24,25(OH)2D (ng/ml) | 2.5 1.7, 3.9 | 1.0 0.5, 2.2 | 0.5 0.3, 0.8 | <0.001 |
| b) underlying renal disease | ||||
|---|---|---|---|---|
| CAKUT n = 100 | GN n = 21 | FSGS n = 27 | p1 | |
| Total 25(OH)D (ng/ml) | 29.1 (17.5, 34.7) | 15.9 (8.8, 20.6) | 10.4 (4.9, 14.9) | <0.001 |
| Free 25(OH)D (pg/ml) | 9.6 (6.8, 14.3) | 4.8 (3.9, 6.7) | 4.2 (2.0, 6.7) | <0.001 |
| Bioavailable 25(OH)D (ng/ml) | 3.4 (2.4, 5.0) | 1.4 (1.1, 2.3) | 0.8 (0.7, 2.1) | <0.001 |
| Albumin (g/dl) | 4.1 (3.7, 4.2) | 3.4 (3.0, 3.6) | 3.3 (2.6, 3.6) | <0.001 |
| DBP (mg/dl) | 20.6 (13.6, 28.7) | 20.8 (10.1, 28.2) | 16.8 (9.9, 24.2) | 0.55 |
| 1,25(OH)2D (pg/ml) | 35.5 24, 43.1 | 22.7 13.2, 34.3 | 19.4 15.1, 28.1 | <0.001 |
| 24,25(OH)2D (ng/ml) | 1.8 0.7, 2.7 | 1.2 0.5, 1.9 | 0.4 0.3, 0.5 | <0.001 |
Results presented as median (IQR)
1
ANOVA, Kruskal-Wallis or test for trend among groups.
CAKUT = congenital anomalies of the kidney and urinary tract. GN = glomerulonephritis. FSGS = focal segmental glomerulosclerosis.