Table 4. Summary of meta-analysis of association of the PPARG polymorphisms and essential hypertension risk.

SNPs	Subgroup	Dominant model					Allelic model
		N	OR (95% CI)	POR	I2 (%)	PQ	OR (95% CI)	POR	I2 (%)	PQ
Pro12Ala	All	17	0.771 (0.627–0.946)	0.013	54.0	0.004	0.757 (0.624–0.918)	0.005	57.9	0.002
	Ethnicity
	Asian	14	0.749 (0.595–0.944)	0.014	52.5	0.011	0.726 (0.587–0.887)	0.003	54.6	0.007
	Caucasian	3	0.847 (0.531–1.351)	0.486	59.6	0.084	0.865 (0.563–1.329)	0.509	61.6	0.074
	Genotyping method
	PCR-RFLP	13	0.826 (0.623–1.095)	0.184	48.0	0.027	0.790 (0.596–1.047)	0.101	53.9	0.011
	Others	4	0.676 (0.515–0.889)	0.005	59.7	0.059	0.690 (0.543–0.879)	0.003	63.2	0.043
	Source of control
	HB	10	0.921 (0.697–1.217)	0.562	28.1	0.186	0.863 (0.652–1.141)	0.301	37.7	0.108
	PB	7	0.658 (0.514–0.946)	0.001	55.1	0.038	0.675 (0.532–0.855)	0.001	62.3	0.014
	HWE
	P>0.05	14	0.752 (0.609–0.928)	0.008	52.3	0.012	0.745 (0.620–0.894)	0.002	49.4	0.019
	P<0.05	3	0.805 (0.370–1.750)	0.584	62.6	0.009	0.664 (0.244–1.809)	0.423	81.3	0.005
C161T	All	5	0.734 (0.499–1.081)	0.117	78.9	0.001	0.791 (0.587–1.064)	0.121	75.0	0.003
	Ethnicity
	Asian	4	0.653 (0.439–0.972)	0.036	78.1	0.003	0.719 (0.537–0.963)	0.027	72.2	0.013
	Caucasian	1	1.290 (0.748–2.227)	0.36	0	0	1.306 (0.807–2.122)	0.282	0	0
	Genotyping method
	PCR-RFLP	3	0.646 (0.354–1.178)	0.154	81.7	0.004	0.727 (0.444–1.191)	0.206	79.7	0.007
	Others	2	0.907 (0.709–1.160)	0.438	0	0.673	0.907 (0.745–1.104)	0.329	0	0.919
	Source of control
	HB	3	0.646 (0.354–1.178)	0.154	81.7	0.004	0.727 (0.444–1.191)	0.206	79.7	0.007
	PB	2	0.907 (0.709–1.160)	0.438	0	0.673	0.907 (0.745–1.104)	0.329	0	0.919

N, number of study; HWE, Hardy-Weinberg equilibrium; PCR-RFLP, polymerase chain reaction-restriction fragment length polymorphism;HB, hospital based; PH, population based.