Table 3 Effect of vitamin D supplementation on C-peptide (ng/mL) at 3 months and 6 months stratified by baseline C-peptide.

From: Effects of Vitamin D Supplementation on C-peptide and 25-hydroxyvitamin D Concentrations at 3 and 6 Months

 

Vitamin D Dose, IU/d

  

Parameter

Placebo

1000

2000

4000

Mo Change in C-peptide per 1000 IU/d#

P-Value

No. (at baseline)

81

81

83

83

  

C-Peptide, Tertile 1 *

      

 No. in Tertile

27

30

28

25

  

 Baseline

2.10 (0.14)

2.06 (0.13)

1.97 (0.14)

2.13 (0.14)

  

 3 mo C-Peptide

2.85 (0.25)

3.28 (0.33)

3.38 (0.37)

3.91 (0.55)

  

 6 mo C-peptide

3.78 (0.40)

2.67 (0.34)

4.67 (0.59)

2.99 (0.47)

  

 Difference C-Peptide (0-3)

0.76(0.21)

1.24 (0.24)

1.41 (0.30)

1.78 (0.53)

0.24 (0.12)

0.04

 Difference C-peptide (3-6)

1.66 (0.33)

0.63 (0.27)

2.69 (0.52)

0.85 (0.53)

−0.31 (0.17)

0.07

 Difference C-peptide (0-6)

0.95 (0.41)

−0.62(0.27)

1.14 (0.62)

−0.83 (0.57)

−0.08 (0.15)

0.57

C-Peptide, Tertile 2 *

 No. in Tertile

26

24

29

30

  

 Baseline

3.79 (0.12)

3.76 (0.12)

3.85 (0.12)

3.91 (0.11)

  

 3 mo C-Peptide

4.08 (0.42)

4.20 (0.35)

4.04 (0.39)

5.50 (0.54)

  

 6 mo C-peptide

4.47 (0.39)

4.37 (0.50)

4.58 (0.42)

4.37 (0.48)

  

 Difference C-Peptide (0-3)

0.22 (0.46)

0.35 (0.37)

0.20(0.38)

1.55(0.57)

0.34 (0.16)

0.03

 Difference C-peptide (3-6)

0.59 (0.40)

0.52 (0.47)

0.74 (0.38)

0.38 (0.53)

−0.34 (0.16)

0.03

 Difference C-peptide (0-6)

0.49 (0.38)

0.17 (0.62)

0.67 (0.32)

−0.90 (0.51)

−0.05 (0.15)

0.74

C-Peptide, Tertile 3 *

 No. in Tertile

28

27

26

28

  

 Baseline

7.36 (0.54)

7.50 (0.40)

6.87 (0.44)

7.22 (0.33)

  

 3 mo C-Peptide

4.68 (0.34)

5.63 (0.63)

5.20 (0.48)

7.68 (0.98)

  

 6 mo C-peptide

5.89 (0.60)

5.42 (0.55)

5.86 (0.58)

7.20 (1.16)

  

 Difference C-Peptide (0-3)

−2.33 (0.58)

−2.06 (0.59)

−1.71 (0.54)

0.39 (0.84)

0.70 (0.22)

0.002

 Difference C-peptide (3-6)

−1.53 (0.55)

−2.17 (0.74)

−1.10 (0.59)

−0.09 (1.06)

−0.24 (0.20)

0.23

 Difference C-peptide (0-6)

0.75 (0.55)

−0.24 (0.80)

0.79 (0.46)

−0.48 (0.56)

0.43 (0.25)

0.09

  1. #0-3 month change in C-peptide per 1000 IU/d of vitamin D supplementation, 3-6 month change in C-peptide per 1000 IU/d of vitamin D supplementation, 0-6 month change in C-peptide per 1000 IU/d of vitamin D supplementation adjusted for baseline C-peptide.
  2. *C-peptide ng/mL: Mean(Standard Error) IU, international unit.
  3. Difference C-Peptide (0-3)= Month 3 C-peptide concentration ng/ml- Month 0 C-peptide concentration ng/ml: Mean (SE). Difference C-Peptide (3-6)= Month 6 C-peptide concentration ng/mL- Month 3 C-peptide concentration ng/mL: Mean (SE). Difference C-Peptide (0-6)= Month 6 C-peptide concentration ng/mL- Month 0 C-peptide concentration ng/mL: Mean (SE). The numbers do not always sum to group totals due to missing information for some variables.
Back to article page