Are There Any Common Genetic Risk Markers for Rheumatoid Arthritis and Periodontal Diseases? A Case-Control Study

Table 6

Binary logistic regression analyses investigating the impact of A allele of rs240561 of IFNγ (a) on the incidence of severe PD in a cohort of RA patients and (b) on the incidence of comorbidity of RA and PD versus controls without both, RA and severe PD.

(a) RA patients with severe PD vs. RA patients who do not have severe PD

Variables	Regression coefficient	value	Odds ratio	95% confidence interval
				Lower	Upper
Age	0.031	0.046	1.03	1.01	1.06
Male gender	1.149	0.002	3.15	1.53	6.49
Current smoker	0.893	0.024	2.44	1.13	5.3
P.g. positive	0.944	0.009	2.57	1.26	5.24
A allele	0.684	0.068	1.98	0.95	4.13

(b) Patients with comorbidity of RA and severe PD vs. controls without both, RA and severe PD

Variables	Regression coefficient	value	Odds ratio	95% confidence interval
				Lower	Upper
Age	0.131	<0.001	1.12	1.08	1.17
Male gender	0.123	0.767	1.13	0.50	2.55
Current smoker	1.87	<0.001	6.49	2.69	15.6
P.g. positive	1.54	<0.001	4.67	2.07	10.5
A allele	0.977	0.024	2.66	1.14	6.20

Age, gender, smoking status, and the occurrence of Porphyromonas gingivalis (P.g.) were considered as confounding factors.