Table 2.
Demographic characteristics and laboratory blood parameters; data are presented as mean ± SD and median, with IQR in brackets, or as absolute numbers (n) with percentage (% of the referring group) in brackets
| Total (n = 165) | Non-CKD (n = 33, 20.0%) | CKD 1 (n = 21, 12.7%) | CKD 2 (n = 27, 16.4%) | CKD 3 (n = 43, 26.1%) | CKD 4 (n = 38, 23.0%) | CKD 5 (n = 3, 1.8%) | P-value | |
|---|---|---|---|---|---|---|---|---|
| Age (years) | 61.9 ± 14.4, 65.0 (51.0, 73.0) | 60.8 ± 14.2, 66.0 (62.0, 67.0) | 56.0± 11.3, 55.0 (45.0, 63.0) | 60.5 ± 12.4, 62.0 (48.0, 72.0) | 64.0 ± 17.6, 71.0 (52.5, 77.0) | 63.9 ± 12.1, 66.0 (56.3, 73.0) | 63.3 ± 16.0, 53.0 (52.0, 69.5) | 0.159 |
| Gender (m/f in %) | 110/55 (66.7/33.3) | 20/13 (60.6/39.4) | 15/6 (71.4/28.6) | 18/9 (66.7/33.3) | 28/15 (65.1/34.9) | 26/12 (68.4/31.6) | 3/0 (100/0) | 0.888 |
| Hypertension | 74 (44, 8%) | 1 (3%) | 12 (57%) | 17 (60, 7%) | 19 (44%) | 23 (60, 5%) | 3 | |
| NIDDM | 27 | 0 | 6 (28, 5%) | 5 (17, 8%) | 8 (18, 6%) | 7 (18, 4%) | 1 | |
| IDDM | 13 | 0 | 0 | 0 | 5 (11, 6%) | 8 (21%) | 0 | |
| GN, others | 1 former GN in complete remission | mGN (1) SLE (1) ANCA (1) | GN 7 (25%), pHPT (2), sarkoidosis (3), myeloma (2) | GN 7 (16, 2%), PN 2 (4, 6%), myeloma 6 (13, 9%) | GN 8 (21%), toxN 6 (15, 7%), obstrN 3 (7, 9%) | mGN (1) | ||
| Proteinuria <1 g/g creat | 1 | 9 (42%) | 13 (46%) | 12 (28%) | 15 (39%) | 0 | ||
| Proteinuria >1 g/g creat | 0 | 1 (4, 7%) | 2 (7, 1%) | 8 (18, 6%) | 15 (31, 8) | 3 | ||
| Uric acid (µmol/L) | 375.3 ± 93.9, 369.0 (315.5, 424.1) | 316.0 ± 79.7, 315.5 (267.9, 381.0) | 353.4 ± 81.0, 330.4 (293.2, 431.5) | 332.5 ± 76.6, 333.3 (273.8, 378.0) | 391.9 ± 64.2, 372.0 (345.2, 422.6) | 469.0 ± 92.8, 422.6 (401.8, 523.8) | 333.3 ± 0.0, 333.3 (333.3, 333.3) | <0.001 |
| C-reactive protein (mg/dL) | 1.3 ± 1.9, 0.9 (0.4, 1.5) | 0.6 ± 0.2, 0.5 (0.4, 0.6) | 0.8 ± 0.5, 0.7 (0.6, 0.9) | 1.4 ± 0.2, 1.4 (1.3, 1.5) | 0.7 ± 0.4, 0.7 (0.4, 1.1) | 2.5 ± 3.2, 1.7 (1.2, 2.0) | 1.4 ± 0.0, 1.4 (1.4, 1.4) | <0.001 |
| Urea (mmol/L) | 11.9 ± 8.0, 8.4 (5.9, 16.7) | 5.9 ± 1.6, 5.7 (4.9, 6.8) | 5.1 ± 1.2, 4.9 (4.6, 5.9) | 7.3 ± 3.4, 6.2 (6.0, 7.5) | 11.9 ± 4.4, 11.8 (7.9, 15.5) | 21.8 ± 6.5, 20.2 (16.7, 26.7) | 28.4 ± 4.3, 29.5 (26.1, 31.2) | <0.001 |
| Sodium (mmol/L) | 138.0 ± 12.1, 139.0 (138.0, 141.0) | 135.1 ± 19.9, 139.0 (138.0, 140.0) | 138.2 ± 3.8, 138.0 (137.0, 141.0) | 139.4 ± 2.9, 139.0 (139.0, 140.0) | 139.1 ± 4.0, 139.0 (137.5, 141.0) | 137.4 ± 17.0 140.0, (139.0, 142.8) | 141.7 ± 0.5, 142.0 (141.5, 142.0) | 0.088 |
| Potassium (mmol/L) | 4.4 ± 0.6, 4.3 (4.0, 4.7) | 4.2 ± 0.4, 4.1 (3.9, 4.5) | 4.2 ± 0.9, 4.0 (3.9, 4.3) | 4.3 ± 0.5, 4.3 (4.0, 4.6) | 4.5 ± 0.5, 4.4 (4.2, 4.8) | 4.7 ± 0.7, 4.7 (4.2, 5.1) | 4.7 ± 0.2, 4.7 (4.6, 4.9) | <0.001 |
| Calcium (mmol/L) | 2.3 ± 0.2, 2.4 (2.3, 2.4) | 2.4 ± 0.1, 2.4 (2.3, 2.5) | 2.4 ± 0.1, 2.4 (2.3, 2.4) | 2.4 ± 0.1, 2.4 (2.3, 2.4) | 2.3 ± 0.2, 2.3 (2.3, 2.4) | 2.36 ± 0.2, 2.3 (2.2, 2.4) | 2.3 ± 0.1, 2.3 (2.3, 2.4) | 0.096 |
| Phosphate (mmol/L) | 1.2 ± 0.3, 1.1 (1.0, 1.3) | 1.1 ± 0.2, 1.1 (1.0, 1.2) | 1.0 ± 0.2, 1.1 (0.9, 1.1) | 1.0 ± 0.2, 1.0 (0.9, 1.2) | 1.1 ± 0.2, 1.1 (0.9, 1.3) | 1.4 ± 0.5, 1.3 (1.1, 1.5) | 1.6 ± 0.6, 1.6 (1.3, 2.0) | <0.001 |
| Total protein (g/L) | 75 ± 28, 73 (67, 76) | 73 ± 5, 73 (69, 77) | 73 ± 6, 74 (67, 77) | 73 ± 6, 74 (69, 76) | 74 ± 10, 73 (70, 76) | 84 ± 63, 67 (65, 73) | 73 ± 0, 73 (73, 73) | 0.325 |
| Cholesterol (mmol/L) | 5.7 ± 1.6, 5.8 (4.6, 7.0) | 6.6 ± 1.0, 6.6 (5.8, 7.4) | 6.0 ± 1.3, 6.1 (5.3, 7.2) | 5.5 ± 1.3, 5.1 (4.8, 6.4) | 4.8 ± 1.8, 4.4 (3.7, 5.0) | 6.0 ± 1.3, 5.9 (5.1, 6.9) | 4.9 ± 0.0, 4.9 (4.9 , 4.9) | <0.001 |
| HDL (mmol/L) | 1.5 ± 0.4, 1.4 (1.2, 1.7) | 1.6 ± 0.3, 1.6 (1.4, 1.8) | 1.4 ± 0.5, 1.3 (1.0, 1.7) | 1.4 ± 0.5, 1.2 (1.1, 1.7) | 1.4 ± 0.4, 1.4 (1.2, 1.6) | 1.5 ± 0.6, 1.3 (1.2, 1.6) | 1.1 ± 0.0, 1.1 (1.1, 1.1) | 0.112 |
| LDL (mmol/L) | 4.0 ± 1.3, 4.0 (3.0, 5.0) | 4.6 ± 0.8, 4.6 (4.0, 5.1) | 4.4 ± 1.2, 4.4 (3.9, 5.0) | 3.7 ± 0.8, 3.7 (3.1, 4.5) | 3.2 ± 1.4, 2.7 (2.4, 3.2) | 4.0 ± 1.3, 4.1 (3.1, 4.9) | 3.6 ± 0.0, 3.6 (3.6, 3.6) | <0.001 |
| Triglyceride (mmol/L) | 1.9 ± 1.4, 1.5 (1.0, 2.2) | 1.5 ± 0.5, 1.5 (1.1, 1.9) | 1.8 ± 0.8, 1.7 (1.3, 1.9) | 2.4 ± 2.1, 1.7 (1.1, 2.6) | 1.7 ± 1.2, 1.2 (0.9, 2.2) | 2.4 ± 1.7, 2.1 (1.1, 3.0) | 1.9 ± 0.0, 1.9 (1.9, 1.9) | 0.256 |
| Haemoglobin (mmol/L) | 8.3 ± 1.6, 8.7 (7.9, 9.2) | 8.9 ± 0.5, 8.9 (8.4, 9.2) | 8.8 ± 1.5, 9.2 (8.7, 9.5) | 8.2 ± 1.8, 8.6 (7.9, 9.2) | 8.0 ± 2.1, 8.1 (7.0, 9.0) | 7.7 ± 1.4, 8.2 (6.8, 8.9) | 7.8 ± 0.0, 7.8 (7.8, 7.8) | 0.006 |
| Leucocyte count (10e9/L) | 8.0 ± 7.4, 6.9 (5.9, 8.2) | 8.1 ± 11.1, 6.4 (5.4, 7.1) | 10.0 ± 10.0, 6.6 (6.1, 9.5) | 7.6 ± 2.6, 8.0 (6.8, 8.6) | 7.5 ± 4.6, 6.9 (6.1, 7.8) | 7.2 ± 1.3, 7.4 (6.2, 8.4) | 9.2 ± 0.0, 9.2 (9.2, 9.2) | 0.057 |
| Kidney biomarker level | ||||||||
| Uromodulin (ng/mL) | 115.6 ± 101.0, 84.8 (37.0, 180.0) | 260.4 ± 101.6, 227.6 (194.4, 277.8) | 150.7 ± 54.8, 153.4 (121.5, 180.7) | 116.7 ± 44.5, 111.8 (80.9, 139.4) | 70.5 ± 47.1, 51.8 (36.1, 86.2) | 29.1 ± 13.2, 30.3 (19.2, 38.0) | 10.3 ± 7.0, 12.7 (6.7, 15.1) | <0.001 |
| Cystatin C (nmol/L) | 147.1 ± 93.8, 113.8 (72.7, 206.3) | 66.7 ± 10.1, 68.2 (62.9, 73.4) | 62.1 ± 10.9, 66.7 (55.4, 70.4) | 91.5 ± 9.5, 89.1 (85.0, 98.9) | 151.9 ± 27.4, 147.6 (127.0, 176.4) | 273.8 ± 39.3, 271.1 (247.9, 304.3) | 453.1 ± 70.5, 445.7 (408.2, 494.3) | <0.001 |
| Creatinine (µmol/L) | 176.9 ± 126.1, 127.0 (93.0, 223.3) | 96.7 ± 22.1, 94.0 (80.0, 117.0) | 82.4 ± 16.8, 76.9 (72.0, 93.0) | 107.0 ± 21.8, 105.0 (91.5, 119.2) | 169.3 ± 52.7, 160.9 (125.0, 206.0) | 333.5 ± 131.5, 316.5 (246.1, 383.1) | 669.5 ± 153.0, 670.0 (575.9, 763.3) | <0.001 |
| BUN (mmol/L) | 11.9 ± 8.0, 8.4 (5.9, 16.6) | 5.9 ± 1.6, 5.7 (4.9, 6.8) | 5.1 ± 1.2, 4.9 (4.6 , 5.9) | 7.3 ± 3.4, 6.2 (6.0 , 7.4) | 11.9 ± 4.4, 11.8 (7.9 , 15.5) | 21.8 ± 6.5, 20.2 (16.7 , 26.7) | 28.3 ± 4.3, 29.4 (26.0 , 31.2) | <0.001 |
| eGFRHoek (mL/min) | 64.2 ± 37.9, 57.7 (29.7, 92.9) | 104.6 ± 20.7, 99.3 (91.9, 108.0) | 114.0 ± 26.8, 101.0 (96.0, 123.2) | 73.6 ± 7.8, 74.9 (67.1, 78.8) | 43.7 ± 8.7, 43.6 (35.7, 51.1) | 22.0 ± 3.8, 21.8 (19.1, 24.3) | 11.8 ± 2.5, 12.0 (10.3, 13.4) | <0.001 |
| eGFRCKD-EPI (mL/min) | 49.4 ± 31.1, 44.0 (20.5, 71.5) | 78.8 ± 17.5, 76.5 (65.1, 86.2) | 92.8 ± 18.3, 88.9 (85.1, 97.0) | 60.1 ± 11.5, 61.6 (51.5, 69.5) | 32.5 ± 8.7, 31.4 (25.7, 39.5) | 14.5 ± 4.0, 14.2 (11.6, 16.9) | 6.7 ± 1.2, 7.0 (6.0, 7.5) | <0.001 |
NIDDM, non-insulin-dependent diabetes mellitus type II; IDDM, insulin-dependent diabetes mellitus type II; GN, glomerulonephritis: biopsy proven; pHPT, primary hyperparathyroidism; obstrN, obstructive nephropathy; toxN, CKD due to former nephrotoxic chemotherapy, HDL, high-density lipoprotein; LDL, low-density lipoprotein.