Interactions between CagA and smoking in gastric cancer

Table 3 Odds ratios of CagA positive Helicobacter pylori infection and smoking in non-cardiac cancer n (%)

	Cases (n = 257)	Control (n = 514)	Crude		Adjusted
			OR	95% CI	OR	95% CI
CagA
Tertile 1	45 (17.5)	249 (48.5)	1.0		1.0
Tertile 2	85 (33.0)	170 (33.0)	2.3	1.2-3.9	3.8	1.4-7.2
Tertile 3	127 (49.5)	95 (18.5)	4.1	2.7-6.3	12.41	6.1-20.3
P value				0		0.003
Smoking status
Never smoked	90 (35.0)	355 (69.0)	1.0		1.0
Smoking	167 (65.0)	159 (31.0)	3.6a	2.5-5.3	5.42a	2.3-9.0

^aP < 0.05.

¹Adjusted for education, alcohol consumption, smoking and family history of gastric cancer;

²Adjusted for education, alcohol consumption, family history of gastric cancer and Helicobacter pylori infection. CagA: Cytotoxin-associated gene; OR: Odds ratio.