Meta-Analysis of the Association between Vitamin D Receptor Polymorphisms and the Risk of Autoimmune Thyroid Disease

Table 2

The association between VDR rs731236 polymorphism and AITD risk.

Comparison model	Subgroup	The number of studies	Sample size (cases/controls)	I^2		Effect model	OR (95% CI)
Homozygote comparison (CC versus TT)	AITD	14	1930/1341	54%	0.008	Random	0.67 [0.48, 0.93]	0.02
	HT	7	625/579	41%	0.12	Fixed	0.58 [0.40, 0.85]	0.005
	GD	9	1305/1087	53%	0.03	Random	0.71 [0.49, 1.04]	0.08
	European	9	930/891	53%	0.03	Random	0.75 [0.54, 1.05]	0.09
	Asian	4	942/424	47%	0.13	Fixed	0.49 [0.28, 0.86]	0.01
	African	1	58/26	—	—	—	0.28 [0.10, 0.80]	0.02
Heterozygote comparison (CT versus TT)	AITD	14	2674/1949	70%	<0.001	Random	0.82 [0.64, 1.05]	0.11
	HT	7	827/778	72%	0.002	Random	0.82 [0.52, 1.29]	0.38
	GD	9	1847/1546	65%	0.004	Random	0.85 [0.65, 1.11]	0.22
	European	9	1471/1354	50%	0.04	Random	0.97 [0.84, 1.13]	0.71
	Asian	4	1123/551	82%	<0.001	Random	0.69 [0.35, 1.35]	0.27
	African	1	80/44	—	—	—	0.34 [0.16, 0.74]	0.007
Dominant model (CC + CT versus TT)	AITD	14	2950/2254	75%	<0.001	Random	0.79 [0.61, 1.02]	0.07
	HT	7	895/861	75%	<0.001	Random	0.81 [0.51, 1.29]	0.38
	GD	9	2055/1769	71%	<0.001	Random	0.81 [0.61, 1.07]	0.13
	European	9	1705/1615	62%	0.007	Random	0.90 [0.70, 1.15]	0.39
	Asian	4	1155/584	84%	<0.001	Random	0.69 [0.34, 1.37]	0.29
	African	1	90/55	—	—	—	0.33 [0.16, 0.68]	0.003
Recessive model (CC versus CT + TT)	AITD	14	2950/2254	7%	0.37	Fixed	0.80 [0.66, 0.95]	0.01
	HT	7	895/861	0%	0.44	Fixed	0.71 [0.50, 1.01]	0.06
	GD	9	2055/1769	6%	0.38	Fixed	0.84 [0.68, 1.03]	0.09
	European	9	1705/1615	26%	0.21	Fixed	0.83 [0.68, 1.01]	0.06
	Asian	4	1155/584	0%	0.61	Fixed	0.67 [0.39, 1.17]	0.16
	African	1	90/55	—	—	—	0.50 [0.20, 1.27]	0.14
Allele comparison (C versus T)	AITD	15	3050/2354	73%	<0.001	Random	0.85 [0.71, 1.02]	0.09
	HT	7	895/861	70%	0.003	Random	0.85 [0.61, 1.19]	0.35
	GD	9	2055/1769	70%	<0.001	Random	0.83 [0.68, 1.02]	0.08
	European	9	1705/1615	66%	0.003	Random	0.89 [0.74, 1.07]	0.21
	Asian	4	1155/584	79%	0.003	Random	0.77 [0.47, 1.26]	0.30
	African	2	190/155	92%	<0.001	Random	0.84 [0.27, 2.54]	0.75
		14	2950/2254	72%	<0.001	Random	0.82 [0.68, 0.99]	0.04

P_H: value of heterogeneity test; P_Z: value of Z test.