Table 5.

Overall and stratum-specific adjusted odds ratios (OR) in the presence of gene-gene interaction: Factor V Leiden (FVL), prothrombin (PT) 20210A and methylenetetraydrofolate reductase (MTHFR) C677T

	Cases/Controls Exposed	Cases/Controls Not exposed	ORa	CIa	I-sq (CI), %	p-valueb	p-value for interaction
FVL & PT 20210A Carriers
Overall	187/121	4,156/3,604	3.43	(1.64-7.13)	59.1 (10.7-81.3)	0.017
<45 y.o.	64/61	363/811	3.54	(0.93-13.40)	67.6 (5.8-88.9)	0.026	0.666
>= 45 y.o.	82/59	1,756/1,593	2.54	(1.26-5.12)	28.4 (0.0-69.2)	0.211
Men	92/59	1,587/1,234	3.45	(1.47-8.10)	39.5 (0.0-77.6)	0.158	0.847
Women	89/61	2,252/2,309	3.04	(1.16-7.95)	55.0 (0.0-80.7)	0.038
- Not using OCc	---	---	ncd	.	nc	nc
- Using OC	14/2	92/225	17.03	(3.79-76.47)	nc	nc
MTHFR C677T Homozygous & FVL Carriers
Overall	44/71	1,466/10,298	3.79	(1.71-8.40)	37.2 (0.0-78.4)	0.189
<45 y.o.	21/10	352/777	4.86	(2.23-10.58)	0.0 (0.0-59.9)	0.772	0.527
>=45 y.o.	13/45	549/7,186	3.19	(1.11-9.12)	48.7 (0.0-85.1)	0.142
Men	11/27	356/4,370	3.13	(1.30-7.52)	0.0 (0.0-79.4)	0.603	0.759
Women	22/43	656/5,578	3.91	(1.27-12.07)	42.3 (0.0-80.6)	0.158
- Not using OC	4/1	88/209	9.31	(1.02-84.78)	nc	nc	0.834
- Using OC	12/4	94/223	7.13	(2.24-22.70)	nc	nc
MTHFR C677T Homozygous & PT 20210A Carriers
Overall	12/25	1,096/9,154	1.94	(0.71-5.33)	0.0 (0.0-19.5)	0.879
<45 y.o.	3/3	161/181	1.76	(0.32-9.53)	0.0 (0.0-0.0)	0.787	0.791
>= 45 y.o.	9/16	678/6.940	2.34	(0.64-8.54)	0.0 (0.0-0.0)	0.893
Men	7/13	329/4.111	3.17	(1.00-10.05)	0.0 (0.0-0.0)	0.329	0.506
Women	1/1	182/71	1.10	(0.06-19.98)	nc	nc
- Not using OC	---	---	nc	.	nc	nc
- Using OC	---	---	nc	.	nc	nc

^aOdds ratio (OR) adjusted for age and gender; CI: Confidence Interval

^bfrom Q-square test, random effects model

^cOC: oral contraceptives

^dnc: not computable