Table 1 Patient demographics and clinical characteristics

Age (years)

47.82 ± 15.45

45.36 ± 14.46

51.11 ± 16.12

< 0.001

Sex (male)/N (%)

481 (58.3%)

263 (55.8%)

218 (61.7%)

0.088

BMI, kg/m²

22.98 ± 3.62

22.89 ± 3.74

23.1 ± 3.46

0.421

Body surface area (m²)

1.61 ± 0.19

1.6 ± 0.19

1.62 ± 0.18

0.350

Marital status

0.216

 Unmarried

62 (7.5%)

42 (8.9%)

20 (5.6%)

 Married

755 (91.6%)

426 (90.4%)

329 (93.2%)

 Divorced

6 (0.7%)

3 (0.6%)

3 (0.8%)

 Widowed

1 (0.1%)

0

1 (0.2%)

Education level

0.004

 < 6 years

185 (22.4%)

69 (14.6%)

116 (32.8%)

 6–9 years

305 (37.0%)

177 (37.5%)

128 (36.2%)

 9–12 years

151 (18.3%)

97 (20.8%)

54 (15.2%)

 12–17 years

81 (9.8%)

54 (11.4%)

27 (7.6%)

 > 17 years

3 (0.3%)

2 (0.4%)

1 (0.2%)

Ethnicity, Han/N (%)

781 (94.7%)

449 (95.3%)

332 (94.0%)

0.414

Smoking history/N (%)

204 (24.7%)

115 (24.4%)

89 (25.2%)

0.793

Drinking History/N (%)

129 (15.6%)

73 (15.4%)

56 (15.8%)

0.887

Systolic blood pressure (mmHg)

150.47 ± 26.13

150.14 ± 25.34

150.92 ± 27.19

0.672

Diastolic blood pressure (mmHg)

86.23 ± 18.79

87.12 ± 18.08

85.03 ± 19.67

0.115

Heart rate (bpm)

86.28 ± 13.86

87.09 ± 14.28

85.19 ± 13.22

0.052

Urinary output (ml/24 h)

1013.71 ± 473.18

1048.09 ± 448.97

967.84 ± 500.65

0.016

History of kidney transplantation/N (%)

8 (0.9%)

1 (0.2%)

7 (1.9%)

0.027

History of haemodialysis/N (%)

36 (4.3%)

17 (3.6%)

19 (5.3%)

0.218

Primary renal disease

0.001

 Glomerulonephritis

479 (58.1%)

298 (63.2%)

181 (51.2%)

 Diabetic kidney disease

112 (13.5%)

42 (8.9%)

70 (19.8%)

 Hypertension

21 (2.5%)

9 (1.9%)

12 (3.3%)

 Obstructive nephropathy

10 (1.2%)

6 (1.2%)

4 (1.1%)

 Lupus nephritis

8 (0.9%)

3 (0.6%)

5 (1.4%)

 Cystic kidney disease

5 (0.6%)

3 (0.6%)

2 (0.5%)

 Renal vasculitis

5 (0.6%)

3 (0.6%)

2 (0.5%)

 Others

28 (3.3%)

13 (2.7%)

15 (4.2%)

 Unknown

156 (18.9%)

94 (19.9%)

62 (17.5%)

Comorbidity/N (%)

 Diabetes mellitus

135 (16.3%)

58 (12.3%)

77 (21.8%)

< 0.001

 Hypertension

454 (55.0%)

257 (54.5%)

197 (55.8%)

0.723

 Coronary heart disease or myocardial infarction

48 (5.8%)

25 (5.3%)

23 (6.5%)

0.464

 Congestive heart failure

17 (2.0%)

7 (1.4%)

10 (2.8%)

0.178

 Cardiac arrhythmias

14 (1.6%)

9 (1.9%)

5 (1.4%)

0.587

 History of stroke or cerebral vascular diseases

25 (3.0%)

8 (1.6%)

17 (4.8%)

0.010

 Malignancies

7 (0.8%)

3 (0.6%)

4 (1.1%)

0.442

 Peripheral arterial disease

8 (0.9%)

3 (0.6%)

5 (1.4%)

0.259

 Urology procedures

12 (1.4%)

6 (1.2%)

5 (1.6%)

0.860

History of medication

 ARB

376 (45.6%)

220 (46.7%)

156 (44.1%)

0.473

 ACEI

40 (4.8%)

11 (2.3%)

29 (8.2%)

< 0.001

 CCB

654 (79.3%)

369 (78.3%)

285 (80.7%)

0.401

 Diuretic

160 (19.4%)

99 (21.0%)

61 (17.2%)

0.179

 EPO

604 (73.3%)

368 (78.1%)

236 (66.8%)

< 0.001

 Uric acid-lowering medications

110 (13.3%)

87 (18.4%)

23 (6.5%)

< 0.001

 Iron

144 (17.4%)

74 (15.7%)

70 (19.8%)

0.123

 β-receptor blockade

185 (22.4%)

109 (23.1%)

76 (21.5%)

0.583

 α-receptor blockade

187 (22.6%)

95 (20.1%)

92 (26.0%)

0.046

 α/β-receptor blockade

60 (7.2%)

25 (5.3%)

35 (9.9%)

0.012

 α-ketoacids

226 (27.4%)

112 (23.7%)

114 (32.2%)

0.007

 Antidiabetic agents

115 (13.9%)

49 (10.4%)

66 (18.6%)

0.001

 Lipid-lowering medications

115 (13.9%)

68 (14.4%)

42 (11.8%)

0.289

 Sleep aids

11 (1.3%)

6 (1.2%)

5 (1.4%)

0.109

 Glucocorticoids

16 (1.9%)

6 (1.2%)

10 (2.8%)

0.154

 Immunosuppressive agents

10 (1.2%)

3 (0.6%)

7 (1.9%)

0.081

 Calcimimetic agents

3 (0.3%)

2 (0.4%)

1 (0.2%)

1.000