Table 2 Baseline characteristics of patients according to serum 25-OHD levels

25-OHD (ng/ml)

16.7 ± 0.6

7.3 ± 0.3

< 0.001

Demographic characteristics

Recipient age (years)

40.5 ± 1.3

39.9 ± 1.8

0.793

Recipient gender (% women)

12 (18.5)

19 (46.3)

0.002

Active vitamin D supplementation before KT

13 (20.0)

4 (9.8)

0.186

Etiology of renal failure (%)

Diabetes mellitus

5 (7.7)

5 (12.2)

0.440

Glomerulonephritis

17 (26.2)

15 (36.6)

0.255

Hypertension and others

43 (66.2)

21 (51.2)

0.126

Duration on dialysis (months)

19.1 ± 3.7

13.3 ± 3.9

0.309

History of cardiovascular disease

5 (7.7)

3 (7.3)

0.943

Smoking

15 (23.1)

7 (17.1)

0.458

Body mass index (kg/m²)

23.2 ± 0.4

22.2 ± 0.4

0.102

Predominant RRT modality before KT (%)

Hemodialysis

42 (64.6)

7 (17.1)

< 0.001

Peritoneal dialysis

6 (9.2)

16 (39.0)

< 0.001

Pre-emptive transplantation

17 (26.2)

18 (43.9)

0.058

Transplant type

Living-related donor

44 (67.7)

32 (78.0)

0.249

Living-unrelated donor

20 (30.8)

9 (22.0)

0.321

Deceased donor

1 (1.5)

0 (0.0)

1.000

Donor characteristic

Donor age

35.2 ± 1.4

35.0 ± 1.5

0.922

Donor gender (% women)

36 (56.3)

23 (56.1)

0.988

ABO mismatch (%)

12 (18.8)

3 (7.3)

0.153

Number of HLA mismatches

2.9 ± 0.2

2.8 ± 0.2

0.753

Mismatch at A locus (%)

49 (76.6)

34 (82.9)

0.434

Mismatch at B locus (%)

55 (85.9)

35 (85.4)

0.935

Mismatch at DR locus (%)

52 (81.3)

35 (95.4)

0.585

Biopsy-proven acute rejection episode

2 (3.1)

9 (22.0)

0.003

Laboratory test results

Albumin (g/dl)

4.0 ± 0.1

3.6 ± 0.1

< 0.001

Calcium (mg/dl)

9.4 ± 0.1

8.7 ± 0.2

0.004

Albumin-corrected calcium (mg/dl)

9.4 ± 0.1

9.1 ± 0.2

0.121

Phosphorus (mg/dl)

6.0 ± 0.3

5.5 ± 0.2

0.169

Alkaline phosphatase (IU/l)

68.9 ± 3.3

68.0 ± 4.4

0.864

Parathyroid hormone (intact; pg/ml)

205.4 ± 26.9

203.2 ± 29.2

0.957

Osteocalcin (ng/ml)

47.7 ± 5.4

41.2 ± 5.5

0.429

Hemoglobin (g/l)

9.8 ± 0.2

9.0 ± 0.3

0.028