Table 1 Demographic and clinical characteristics of T2DM patients with or without DR

Male, n (%)

275 (75.3)

192 (74.4)

83 (77.6)

-0.404

0.525

Age, year

55.9 ± 11.3

55.6 ± 11.9

56.6 ± 9.84

-0.830

0.408

Age distribution, n (%)

0.005

1.000

 < 65, year

284 (77.8)

201 (70.8)

81 (70.4)

 ≥ 65, year

81 (22.2)

57 (29.2)

24 (29.6)

Altitude, meters

3657 (3657, 4002)

3657 (3657, 4004)

3657 (3657, 3914)

0.834

0.404

Duration of diabetes, years

5.0 (1.0, 10.0)

3.0 (0.7, 8.0)

10.0 (6.0, 16.0)

-7.598

< 0.001

Smoking, n (%)

93 (25.5)

62 (24.1)

31 (29.2)

-1.033

0.310

Drinking, n (%)

76 (20.8)

51 (19.8)

25 (23.6)

-0.634

0.426

Height, centimeters

169.2 ± 7.26

169.2 ± 7.39

169.0 ± 6.97

-0.220

0.826

Weight, kg

73.7 ± 12.5

74.4 ± 12.9

72.2 ± 11.3

1.557

0.120

Body mass index, kg/m²

25.8 ± 4.01

26.0 ± 4.20

25.2 ± 3.47

1.623

0.106

25-OH-VitD3, ng/mL

10.7 (7.80, 14.5)

11.3 (8.60, 14.6)

9.30 (6.50, 13.5)

3.349

0.001

Hemoglobin, g/L

164.1 ± 22.2

166.3 ± 20.6

158.6 ± 24.9

2.825

0.005

Fasting blood glucose, mmol/L

10.2 ± 5.71

10.1 ± 6.17

10.4 ± 4.42

-0.443

0.658

Fasting insulin, µIU/mL

10.5 (5.69, 19.0)

9.65 (5.45, 17.4)

14.3 (6.28, 27.1)

-2.323

0.020

TSH, mIU/L

2.36 (1.43, 3.94)

2.39 (1.44, 3.94)

2.34 (1.38, 3.94)

0.299

0.765

HbA1c, %

11.8 ± 2.39

11.9 ± 2.47

11.9 ± 2.19

0.339

0.735

Parathyroid hormone, pg/mL

79.7 (58.6, 86.6)

79.7 (61.4, 84.3)

79.7 (56.9, 94.9)

0.320

0.749

Alanine aminotransferase, U/L

30.0 (20.0, 40.0)

34.0 (21.0, 42.0)

26.0 (18.0, 37.4)

2.955

0.003

Aspartate aminotransferase, U/L

22.0 (17.0, 27.2)

22.0 (17.0, 27.2)

21.0 (15.0, 27.2)

1.714

0.086

Total bilirubin, µmol/L

14.7 (10.6, 17.4)

15.0 (11.1, 17.3)

12.9 (9.40, 18.0)

2.200

0.028

Creatinine, µmol/L

65.0 (55.0, 72.0)

65.0 (54.0, 69.3)

66.4 (56.0, 78.0)

-2.413

0.016

Uric acid, mmol/L

348.2 (295.5, 392.5)

348.2 (298.0, 384.3)

348.2 (291.0, 416.0)

1.128

0.259

Calcium, mmol/L

2.16 (2.10, 2.25)

2.16 (2.10, 2.24)

2.15 (2.08, 2.26)

0.135

0.893

Triglycerides, mmol/L

1.36 (1.04, 1.60)

1.34 (1.04, 1.57)

1.39 (1.02, 1.77)

-0.362

0.717

Total cholesterol, mmol/L

4.33 (3.73, 4.78)

4.33 (3.70, 4.73)

4.33 (3.82, 4.97)

1.500

0.134

LDL-C, mmol/L

2.57 (2.09, 2.93)

2.56 (2.07, 2.93)

2.57 (2.18, 2.97)

-0.267

0.789

Atherosclerosis, n (%)

224 (61.4)

153 (63.8)

71 (68.9)

-0.854

0.355

HOMA-β

34.0 (18.2, 73.5)

31.2 (17.7, 71.7)

38.6 (21.1, 77.7)

-1.035

0.301

HOMA-IR

4.51 (2.08, 8.81)

4.09 (2.02, 7.61)

5.71 (2.50, 11.4)

-2.387

0.017