Table 1.
Baseline characteristics of study participants after stratification by CKD stages
| Characteristic | Total (n=444) | Stage 2 (n=89) | Stage 3a (n=128) | Stage 3b (n=145) | Stage 4 (n=82) | P Value |
|---|---|---|---|---|---|---|
| Age (yr) | 65±12 | 58±12 | 65±13 | 68±11 | 68±12 | <0.001 |
| Women, n (%) | 179 (40) | 28 (31) | 64 (50) | 52 (36) | 35 (43) | 0.36 |
| Smokers, n (%) | 44 (10) | 14 (16) | 13 (10) | 11 (8) | 6 (7) | 0.18 |
| Diabetes mellitus, n (%) | 168 (38) | 28 (31) | 57 (45) | 47 (32) | 36 (44) | 0.64 |
| Prevalent CVD, n (%) | 135 (30) | 11 (12) | 45 (35) | 51 (35) | 28 (34) | <0.001 |
| Impaired systolic LV function | 62 (15) | 9 (11) | 12 (9) | 28 (23) | 13 (16) | 0.01 |
| CRP (mg/L) | 2.7 (1.2–5.3) | 2.4 (1.5–4.8) | 2.6 (1.0–5.2) | 2.9 (1.2–6.0) | 3.5 (1.1–5.6) | 0.003 |
| Total cholesterol (mg/dl) | 193±42 | 199±37 | 191±40 | 191±45 | 193±47 | 0.47 |
| HDL-C (mg/dl) | 52±17 | 52±16 | 53±18 | 51±17 | 49±17 | 0.18 |
| LDL-C (mg/dl) | 116±36 | 122±32 | 113±35 | 114±36 | 117±39 | 0.41 |
| BMI (kg/m2) | 30±6 | 30±6 | 31±6 | 30±6 | 29±5 | 0.20 |
| Calcium (mmol/L) | 2.4±0.1 | 2.4±0.1 | 2.4±0.1 | 2.4±0.1 | 2.3±0.2 | 0.19 |
| Phosphate (mg/dl) | 3.4±0.7 | 3.0±0.5 | 3.3±0.5 | 3.4±0.8 | 3.9±0.7 | <0.001 |
| FGF-23 (rU/ml) | 102 (64–164) | 62 (46–90) | 74 (54–105) | 128 (92–195) | 179 (140–291) | <0.001 |
| sKlotho (pg/ml) | 397 (326–485) | 433 (369–581) | 412 (344–493) | 374 (299–454) | 382 (303–459) | 0.02 |
| PTH (pg/ml) | 53 (37–84) | 41 (32–54) | 44 (32–57) | 62 (42–96) | 111 (67–162) | <0.001 |
| eGFR (ml/min per 1.73 m2) | 45±16 | 68±6 | 52±4 | 38±4 | 22±4 | <0.001 |
| UAE (mg/g creatinine) | 37 (8–193) | 26 (7–108) | 19 (6–70) | 46 (11–164) | 129 (37–689) | <0.001 |
| FePi (%) | 26±13 | 17±8 | 20±9 | 28±11 | 40±13 | <0.001 |
| β-Blocker use, n (%) | 301 (68) | 45 (51) | 97 (76) | 96 (66) | 63 (77) | 0.001 |
| ACE-I use, n (%) | 165 (37) | 26 (29) | 60 (47) | 43 (30) | 36 (44) | 0.29 |
| Statin use, n (%) | 216 (49) | 29 (33) | 73 (57) | 70 (48) | 44 (54) | 0.01 |
| Unhydroxylated vitamin D3 intake, n (%) | 189 (43) | 38 (43) | 51 (40) | 51 (35) | 49 (60) | 0.01 |
| Active vitamin D3 intake, n (%) | 33 (7) | 1 (1) | 1 (1) | 14 (10) | 17 (21) | <0.001 |
Echocardiographic data were available in 425 patients. Variables are presented as numbers of patients (percentage), as mean±SD, or as median (interquartile range), as appropriate. CVD, cardiovascular disease; LV, left ventricular; CRP, C-reactive protein; HDL-C, HDL cholesterol; LDL-C, LDL cholesterol; BMI, body mass index; FGF-23, fibroblast growth factor-23; sKlotho, soluble Klotho; PTH, parathyroid hormone; UAE, urinary albumin excretion; FePi, urinary fractional phosphate excretion; ACE-I, angiotensin-converting enzyme inhibitor.