J Endocrinol Metab

Journal of Endocrinology and Metabolism, ISSN 1923-2861 print, 1923-287X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Endocrinol Metab and Elmer Press Inc

Journal website http://www.jofem.org

Original Article

Volume 6, Number 4, August 2016, pages 116-122

Low Vitamin D Status Is Not Associated With Thyroid Cancer Risk

**Table 1.** Baseline Characteristics Divided by Benign or Malignant Thyroid Nodules
	Total (n = 410)	Benign (n = 366)	Malignant (n = 44)	P value^a
Data were mean ± standard deviation or numbers (%). ^aP values were based on comparisons between benign and malignant thyroid nodule groups. ^bVitamin D insufficiency was defined as serum 25(OH)D levels < 75 nmol/L. ^cCalcium levels were corrected calcium levels calculated on the basis of albumin levels. *P < 0.05. BMI: body mass index; 25(OH)D: 25-hydroxyvitamin D; PTH: parathyroid hormone; free T4; free thyroxine; TSH: thyroid stimulating hormone; TPO-Ab: thyroid peroxidase antibody; Tg-Ab: thyroglobulin antibody.
Age, years	48.2 ± 13.1	48.1 ± 13.3	48.7 ± 11.4	0.805
Sex, male, n (%)	57/410 (13.9%)	54/366 (14.8%)	3/44 (6.8%)	0.173
BMI, kg/m²	24.0 ± 3.6	23.9 ± 3.6	24.6 ± 3.6	0.212
25(OH)D, nmol/L	99.3 ± 57.4	99.1 ± 55.7	102.3 ± 48.7	0.707
Prevalence of vitamin D insufficiency^b, n (%)	165/410 (40.2%)	148/366 (40.4%)	17/44 (38.6%)	0.486
PTH, ng/L	30.4 ± 16.5	30.3 ± 17.0	31.3 ± 12.4	0.697
Calcium^c, mmol/L	2.28 ± 0.11	2.29 ± 0.10	2.25 ± 0.16	0.172
Phosphorous, mmol/L	1.22 ± 0.18	1.21 ± 0.18	1.27 ± 0.20	0.098
Free T4, pmol/L	16.47 ± 5.66	16.47 ± 5.92	16.09 ± 3.09	0.619
TSH, mIU/L	2.96 ± 6.45	3.08 ± 6.79	1.95 ± 1.80	0.276
TPO-Ab, mIU/L	120.91 ± 401.69	128.66 ± 420.77*	54.29 ± 149.89*	0.022*
Tg-Ab, mIU/L	129.89 ± 364.72	132.09 ± 364.20	111.44 ± 372.95	0.726
Positivity of TPO-Ab, n (%)	63/403 (15.4%)	60/361 (16.6%)	3/42 (7.1%)	0.121
Positivity of Tg-Ab, n (%)	95/404 (23.5%)	88/361 (24.4%)	7/43 (16.3%)	0.237
Positivity of TPO-Ab or Tg-Ab, n (%)	110/405 (27.2%)	102/362 (28.2%)	8/43 (18.6%)	0.182

Table 1. Baseline Characteristics Divided by Benign or Malignant Thyroid Nodules

Total (n = 410)

Benign (n = 366)

Malignant (n = 44)

P value^a

Data were mean ± standard deviation or numbers (%). ^aP values were based on comparisons between benign and malignant thyroid nodule groups. ^bVitamin D insufficiency was defined as serum 25(OH)D levels < 75 nmol/L. ^cCalcium levels were corrected calcium levels calculated on the basis of albumin levels. *P < 0.05. BMI: body mass index; 25(OH)D: 25-hydroxyvitamin D; PTH: parathyroid hormone; free T4; free thyroxine; TSH: thyroid stimulating hormone; TPO-Ab: thyroid peroxidase antibody; Tg-Ab: thyroglobulin antibody.

Age, years

48.2 ± 13.1

48.1 ± 13.3

48.7 ± 11.4

0.805

Sex, male, n (%)

57/410 (13.9%)

54/366 (14.8%)

3/44 (6.8%)

0.173

BMI, kg/m²

24.0 ± 3.6

23.9 ± 3.6

24.6 ± 3.6

0.212

25(OH)D, nmol/L

99.3 ± 57.4

99.1 ± 55.7

102.3 ± 48.7

0.707

Prevalence of vitamin D insufficiency^b, n (%)

165/410 (40.2%)

148/366 (40.4%)

17/44 (38.6%)

0.486

PTH, ng/L

30.4 ± 16.5

30.3 ± 17.0

31.3 ± 12.4

0.697

Calcium^c, mmol/L

2.28 ± 0.11

2.29 ± 0.10

2.25 ± 0.16

0.172

Phosphorous, mmol/L

1.22 ± 0.18

1.21 ± 0.18

1.27 ± 0.20

0.098

Free T4, pmol/L

16.47 ± 5.66

16.47 ± 5.92

16.09 ± 3.09

0.619

TSH, mIU/L

2.96 ± 6.45

3.08 ± 6.79

1.95 ± 1.80

0.276

TPO-Ab, mIU/L

120.91 ± 401.69

128.66 ± 420.77*

54.29 ± 149.89*

0.022*

Tg-Ab, mIU/L

129.89 ± 364.72

132.09 ± 364.20

111.44 ± 372.95

0.726

Positivity of TPO-Ab, n (%)

63/403 (15.4%)

60/361 (16.6%)

3/42 (7.1%)

0.121

Positivity of Tg-Ab, n (%)

95/404 (23.5%)

88/361 (24.4%)

7/43 (16.3%)

0.237

Positivity of TPO-Ab or Tg-Ab, n (%)

110/405 (27.2%)

102/362 (28.2%)

8/43 (18.6%)

0.182

**Table 2.** Baseline Characteristics of Thyroid Nodules According to the Presence of Vitamin D Insufficiency
	Vitamin D insufficiency (25(OH)D < 75 nmol/L) (n = 165)	Vitamin D sufficiency (25(OH)D ≥ 75 nmol/L) (n = 245)	P value
Data were mean ± standard deviation or numbers (%). Calcium levels were corrected calcium levels calculated on the basis of albumin levels. *P < 0.05. BMI: body mass index; 25(OH)D: 25-hydroxyvitamin D; PTH: parathyroid hormone; free T4: free thyroxine; TSH: thyroid stimulating hormone; TPO-Ab: thyroid peroxidase antibody; Tg-Ab: thyroglobulin antibody..
Age, years*	46.5 ± 14.4*	49.3 ± 12.0*	0.038*
Sex, male, n (%)*	13/165 (7.9%)*	44/245 (18.0%)*	0.004*
BMI, kg/m²*	23.1 ± 3.3*	24.5 ± 3.8*	0.000*
25(OH)D, nmol/L*	54.91 ± 14.23*	129.29 ± 51.67*	0.000*
PTH, ng/L*	33.9 ± 20.3*	28.1 ± 13.0*	0.001*
Calcium, mmol/L	2.29 ± 0.10	2.28 ± 0.11	0.643
Phosphorous, mmol/L	1.23 ± 0.16	1.22 ± 0.19	0.635
Free T4, pmol/L	16.47 ± 5.66	16.47 ± 5.66	0.859
TSH, mIU/L	3.3 2 ± 7.94	2.71 ± 5.23	0.350
TPO-Ab, mIU/L	152.91 ± 490.59	99.39 ± 328.11	0.224
Tg-Ab, mIU/L	177.65 ± 468.59	97.92 ± 270.57	0.051
Positivity of TPO-Ab, n (%)	30/162 (18.5%)	33/241 (13.7%)	0.191
Positivity of Tg-Ab, n (%)	42/162 (25.9%)	53/242 (21.9%)	0.350
Positivity of TPO-Ab or Tg-Ab, n (%)	51/162 (31.5%)	59/243 (24.3%)	0.110
Prevalence of malignancy, n (%)	17/165 (10.3%)	27/245 (11.0%)	0.818

Table 2. Baseline Characteristics of Thyroid Nodules According to the Presence of Vitamin D Insufficiency

Vitamin D insufficiency (25(OH)D < 75 nmol/L) (n = 165)

Vitamin D sufficiency (25(OH)D ≥ 75 nmol/L) (n = 245)

P value

Data were mean ± standard deviation or numbers (%). Calcium levels were corrected calcium levels calculated on the basis of albumin levels. *P < 0.05. BMI: body mass index; 25(OH)D: 25-hydroxyvitamin D; PTH: parathyroid hormone; free T4: free thyroxine; TSH: thyroid stimulating hormone; TPO-Ab: thyroid peroxidase antibody; Tg-Ab: thyroglobulin antibody..

Age, years*

46.5 ± 14.4*

49.3 ± 12.0*

0.038*

Sex, male, n (%)*

13/165 (7.9%)*

44/245 (18.0%)*

0.004*

BMI, kg/m²*

23.1 ± 3.3*

24.5 ± 3.8*

0.000*

25(OH)D, nmol/L*

54.91 ± 14.23*

129.29 ± 51.67*

0.000*

PTH, ng/L*

33.9 ± 20.3*

28.1 ± 13.0*

0.001*

Calcium, mmol/L

2.29 ± 0.10

2.28 ± 0.11

0.643

Phosphorous, mmol/L

1.23 ± 0.16

1.22 ± 0.19

0.635

Free T4, pmol/L

16.47 ± 5.66

0.859

TSH, mIU/L

3.3 2 ± 7.94

2.71 ± 5.23

0.350

TPO-Ab, mIU/L

152.91 ± 490.59

99.39 ± 328.11

0.224

Tg-Ab, mIU/L

177.65 ± 468.59

97.92 ± 270.57

0.051

Positivity of TPO-Ab, n (%)

30/162 (18.5%)

33/241 (13.7%)

0.191

Positivity of Tg-Ab, n (%)

42/162 (25.9%)

53/242 (21.9%)

0.350

Positivity of TPO-Ab or Tg-Ab, n (%)

51/162 (31.5%)

59/243 (24.3%)

0.110

Prevalence of malignancy, n (%)

17/165 (10.3%)

27/245 (11.0%)

0.818

**Table 3.** Clinicopathologic Characteristics of Differentiated Thyroid Cancers According to the Presence of Vitamin D Insufficiency
	Vitamin D insufficiency (25(OH)D < 75 nmol/L) (n = 12)	Vitamin D sufficiency (25(OH)D ≥ 75 nmol/L) (n = 22)	P value
Data were mean ± standard deviation or numbers (%). *P-values were based on Fisher’s exact test. ^aCalcium levels were corrected calcium levels calculated on the basis of albumin levels. ^bAmerican Joint Committee on Cancer (AJCC) 7th edition/TNM classification system was used for the stage. †P < 0.05. BMI: body mass index; 25(OH)D: 25-hydroxyvitamin D; PTH: parathyroid hormone; free T4: free thyroxine; TSH: thyroid stimulating hormone; TPO-Ab: thyroid peroxidase antibody; Tg-Ab: thyroglobulin antibody.
Age at diagnosis, years	52.7 ± 9.8	47.4 ± 11.2	0.178
Sex, male, n (%)	0 (0%)	3 (13.6%)	0.537*
BMI, kg/m²	23.6 ± 3.0	25.1 ± 3.9	0.249
25(OH)D, nmol/L†	61.2 ± 11.5†	128.3 ± 45.9†	0.000†
PTH, ng/L	32.6 ± 9.6	30.7 ± 9.5	0.592
Calcium^a, mmol/L	2.28 ± 0.08	2.21 ± 0.20	0.242
Phosphorus, mmol/L	1.29 ± 0.11	1.28 ± 0.24	0.833
Free T4, pmol/L†	17.63 ± 3.99†	14.80 ± 2.06†	0.034†
TSH, mIU/L	1.52 ± 0.85	2.39 ± 2.29	0.217
TPO-Ab, mIU/L	91.75 ± 257.62	23.16 ± 20.67	0.377
Tg-Ab, mIU/L	43.23 ± 72.09	21.05 ± 23.37	0.201
Positivity of TPO-Ab, n (%)	1/12 (8.3%)	0/20 (0.0%)	0.375*
Positivity of Tg-Ab, n (%)	2/12 (16.7%)	2/21 (9.5%)	0.610*
Positivity of TPO-Ab or Tg-Ab, n (%)	3/12 (25.0%)	2/21 (9.5%)	0.328*
Age at diagnosis ≥ 45 years	10 (83.3%)	12 (54.5%)	0.140*
Tumor size, cm	1.6 ± 1.3	1.5 ± 1.3	0.962
Tumor size > 1 cm	6 (50.0%)	10 (45.5%)	0.800
T stage^b 3/4	6 (50%)	8 (36.4%)	0.440
Lymph node metastasis	3 (25%)	6 (27.3%)	1.00*
Stage^b III/IV	5 (41.7%)	4 (18.2%)	0.224*
Multifocality	5 (41.7%)	4 (18.2%)	0.224*
Extrathyroidal extension	6 (50%)	8 (36.4%)	0.440
Lymphovascular invasion	0 (0%)	1 (4.5%)	1.00*
Recurrence rate	1 (8.3%)	1 (4.5%)	1.00*
Postoperative hypocalcemia	3 (25.0%)	9 (40.9%)	0.465*

Table 3. Clinicopathologic Characteristics of Differentiated Thyroid Cancers According to the Presence of Vitamin D Insufficiency

Vitamin D insufficiency (25(OH)D < 75 nmol/L) (n = 12)

Vitamin D sufficiency (25(OH)D ≥ 75 nmol/L) (n = 22)

P value

Data were mean ± standard deviation or numbers (%). *P-values were based on Fisher’s exact test. ^aCalcium levels were corrected calcium levels calculated on the basis of albumin levels. ^bAmerican Joint Committee on Cancer (AJCC) 7th edition/TNM classification system was used for the stage. †P < 0.05. BMI: body mass index; 25(OH)D: 25-hydroxyvitamin D; PTH: parathyroid hormone; free T4: free thyroxine; TSH: thyroid stimulating hormone; TPO-Ab: thyroid peroxidase antibody; Tg-Ab: thyroglobulin antibody.

Age at diagnosis, years

52.7 ± 9.8

47.4 ± 11.2

0.178

Sex, male, n (%)

0 (0%)

3 (13.6%)

0.537*

BMI, kg/m²

23.6 ± 3.0

25.1 ± 3.9

0.249

25(OH)D, nmol/L†

61.2 ± 11.5†

128.3 ± 45.9†

0.000†

PTH, ng/L

32.6 ± 9.6

30.7 ± 9.5

0.592

Calcium^a, mmol/L

2.28 ± 0.08

2.21 ± 0.20

0.242

Phosphorus, mmol/L

1.29 ± 0.11

1.28 ± 0.24

0.833

Free T4, pmol/L†

17.63 ± 3.99†

14.80 ± 2.06†

0.034†

TSH, mIU/L

1.52 ± 0.85

2.39 ± 2.29

0.217

TPO-Ab, mIU/L

91.75 ± 257.62

23.16 ± 20.67

0.377

Tg-Ab, mIU/L

43.23 ± 72.09

21.05 ± 23.37

0.201

Positivity of TPO-Ab, n (%)

1/12 (8.3%)

0/20 (0.0%)

0.375*

Positivity of Tg-Ab, n (%)

2/12 (16.7%)

2/21 (9.5%)

0.610*

Positivity of TPO-Ab or Tg-Ab, n (%)

3/12 (25.0%)

2/21 (9.5%)

0.328*

Age at diagnosis ≥ 45 years

10 (83.3%)

12 (54.5%)

0.140*

Tumor size, cm

1.6 ± 1.3

1.5 ± 1.3

0.962

Tumor size > 1 cm

6 (50.0%)

10 (45.5%)

0.800

T stage^b 3/4

6 (50%)

8 (36.4%)

0.440

Lymph node metastasis

3 (25%)

6 (27.3%)

1.00*

Stage^b III/IV

5 (41.7%)

4 (18.2%)

0.224*

Multifocality

5 (41.7%)

4 (18.2%)

0.224*

Extrathyroidal extension

6 (50%)

8 (36.4%)

0.440

Lymphovascular invasion

0 (0%)

1 (4.5%)

1.00*

Recurrence rate

1 (8.3%)

1 (4.5%)

1.00*

Postoperative hypocalcemia

3 (25.0%)

9 (40.9%)

0.465*