Table 1.

Baseline characteristics of study participants after stratification by CKD stages

CharacteristicTotal (n=444)Stage 2 (n=89)Stage 3a (n=128)Stage 3b (n=145)Stage 4 (n=82)P Value
Age (yr)65±1258±1265±1368±1168±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 function62 (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±42199±37191±40191±45193±470.47
HDL-C (mg/dl)52±1752±1653±1851±1749±170.18
LDL-C (mg/dl)116±36122±32113±35114±36117±390.41
BMI (kg/m2)30±630±631±630±629±50.20
Calcium (mmol/L)2.4±0.12.4±0.12.4±0.12.4±0.12.3±0.20.19
Phosphate (mg/dl)3.4±0.73.0±0.53.3±0.53.4±0.83.9±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±1668±652±438±422±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±1317±820±928±1140±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.