Interleukin-6-174G/C Polymorphism Contributes to Periodontitis Susceptibility: An Updated Meta-Analysis of 21 Case-Control Studies

Table 2

Overall and subgroup meta-analyses.

Genetic models and subgroups	Number of studies	Association		Heterogeneity		Model of meta-analysis	Publication bias ()
		OR (95% CI)	P value	(%)	P value
C VS G	19	0.979 (0.714–1.344)	0.897	87.3	0.000	Random	0.517
HWE fulfilled	12	0.770 (0.558–1.064)	0.114	72.4	0.000	Random
Caucasian	8	0.957 (0.670–1.366)	0.807	80.0	0.000	Random
Brazilian	6	0.648 (0.497–0.845)	0.001	49.0	0.081	Fixed
Asian	4	1.881 (0.667–5.305)	0.233	93.7	0.000	Random
Indian	1	NA	NA	NA	NA	NA
No smoke	7	1.032 (0.463–2.296)	0.939	94.7	0.000	Random
Matched gender ratio	10	1.161 (0.869–1.552)	0.311	73.2	0.000	Random
Community control	8	1.040 (0.760–1.424)	0.805	10.3	0.001	Random
Caucasian (HWE fulfilled)	4	0.814 (0.559–1.184)	0.281	73.6	0.281	Random
GC VS GG	18	0.897 (0.516–1.558)	0.699	89.8	0.000	Random	0.035
HWE fulfilled	11	0.690 (0.560–0.849)	0.000	27.3	0.184	Fixed
Caucasian	8	1.066 (0.543–2.093)	0.852	84.9	0.000	Random
Brazilian	5	0.621 (0.441–0.876)	0.007	6.1	0.372	Fixed
Asian	4	1.673 (0.360–7.783)	0.512	89.1	0.000	Random
Indian	1	NA	NA	NA	NA	NA
No smoke	5	0.663 (0.506–0.871)	0.003	25.2	0.245	Fixed
Matched gender ratio	10	1.211 (0.574–2.555)	0.615	91.4	0.000	Random
Community control	8	1.120 (0.445–2.820)	0.809	93.0	0.000	Random
Caucasian in HWE	4	0.752 (0.577–0.980)	0.035	55.7	0.080	Fixed
CC + GC VS GG	19	0.907 (0.616–1.335)	0.621	83.9	0.000	Random	0.021
HWE fulfilled	12	0.690 (0.568–0.838)	0.000	44.3	0.049	Fixed
Caucasian	9	0.974 (0.640–1.482)	0.902	72.4	0.000	Random
Brazilian	5	0.649 (0.470–0.896)	0.009	27.8	0.236	Fixed
Asian	4	2.692 (2.160–3.354)	0.000	0.0	0.830	Fixed
Indian	1	NA	NA	NA	NA	NA
No smoke	6	0.611 (0.274–1.361)	0.228	88.5	0.000	Random
Matched gender ratio	11	1.034 (0.652–1.641)	0.886	81.0	0.000	Random
Community control	9	1.801 (0.575–1.018)	0.952	85.2	0.000	Random
Caucasian in HWE	4	0.737 (0.576–0.944)	0.016	60.8	0.054	Fixed
CC VS GG + GC	17	0.846 (0.404–1.772)	0.657	92.5	0.000	Random	0.762
HWE fulfilled	10	0.896 (0.361–2.226)	0.813	86.5	0.000	Random
Caucasian	9	1.127 (0.495–2.565)	0.775	89.0	0.000	Random
Brazilian	5	0.834 (0.454–1.532)	0.559	40.0	0.155	Fixed
Asian	2	0.996 (0.032–31.216)	0.998	99.2	0.000	Random
Indian	1	NA	NA	NA	NA	NA
No smoke	6	0.625 (0.157–2.488)	0.505	93.2	0.000	Random
Matched gender ratio	12	0.888 (0.357–2.214)	0.799	91.8	0.000	Random
Community control	6	1.009 (0.230–4.436)	0.990	95.0	0.000	Random
Caucasian in HWE	4	1.788 (0.398–8.028)	0.448	94.2	0.000	Random

NA = not available.