. 2014 Sep 8;9(9):e107275. doi: 10.1371/journal.pone.0107275

Table 4. Association between copy number of the GSTT1 gene and risk of prostate cancer according to smoking, alcohol consumption, body mass index and family history of prostate cancer.

	GSTT1 Copy Number						P_trend	P_interaction
	0		1		≥2
	Cases/Controls	OR^a (CI95%)	Cases/Controls	OR^a (CI95%)	Cases/Controls	OR^a (CI95%)
Smoking
Never	89/125	1.0	177/176	1.53 (1.06–2.22)	122/82	2.06 (1.35–3.14)	0.0007	0.21
Former or Current	63/66	1.0	100/105	0.93 (0.57–1.51)	72/65	1.27 (0.75–2.16)	0.37
Alcohol
Never	20/28	1.0	31/48	1.00 (0.46–2.19)	33/21	2.31 (0.99–5.40)	0.05	0.36
Former or Current	132/161	1.0	244/228	1.28 (0.93–1.76)	161/125	1.60 (1.12–2.29)	0.01
BMI
<25	74/94	1.0	138/137	1.29 (0.84–1.96)	83/62	1.79 (1.09–2.95)	0.02	0.95
≥25	79/98	1.0	142/145	1.27 (0.85–1.91)	113/86	1.61 (1.03–2.50)	0.03
Family history of prostate cancer
Without	87/146	1.0^b	162/224	1.24^b (0.87–1.77)	97/108	1.63^b (1.09–2.45)	0.02	0.90
With	29/18	1.0	65/26	1.40^b (0.64–3.03)	54/19	1.92^b (0.84–4.35)	0.12

Adjusted for age and family history of prostate cancer.

Adjusted for age.