Table 1.

MR estimates of assessing the causal association between PD and arthritis..

Exposure	Outcome	N. SNPs	F-statistic	IVW				MR-Egger
				OR (95%CI)	P	Q statistic	Q_pval	OR (95%CI)	P	Intercept	P inter
PD	RA	17	21.22	0.99 (0.87, 1.13)	0.89	25.12	0.07	0.90 (0.67, 1.20)	0.48	0.015	0.47
	OA	18		1.06 (0.99, 1.15)	0.09	14.90	0.60	1.00 (0.87, 1.15)	0.99	0.012	0.30
AgP	RA	12	21.69	1.01 (0.96, 1.05)	0.78	10.92	0.45	0.87 (0.67, 1.14)	0.34	0.041	0.31
	OA	13		0.98 (0.95, 1.02)	0.32	13.35	0.34	0.88 (0.71, 1.10)	0.28	0.031	0.35
CP	RA	20	21.52	1.02 (0.99, 1.05)	0.27	13.86	0.79	0.99 (0.92, 1.07)	0.84	0.011	0.50
	OA	21		1.00 (0.98, 1.02)	0.87	17.41	0.63	0.97 (0.93, 1.02)	0.27	0.013	0.24
RA	PD	63	56.98	1.01 (0.97, 1.06)	0.63	73.98	0.14	0.99 (0.89, 1.10)	0.85	0.003	0.66
OA	PD	26	21.04	0.90 (0.81, 1.00)	0.05	17.61	0.86	0.70 (0.53, 0.94)	0.03	0.026	0.09

AgP, aggressive periodontitis; CI, confidence interval; CP, chronic periodontitis; IVW, inverse variance weighted; N. SNPs, number of SNPs used in MR; OA, osteoarthritis; OR, odds ratio; PD, periodontitis; RA, rheumatoid arthritis.

P_inter, P value for intercept test of multivariable MR Egger.