Table 2.

Status on seropositivity of antibodies to H. pylori in relation to risk of gastric cancer stratified by follow-up time, Shanghai Cohort Study

	H. Pylori Negative		H. Pylori Positive
	N	OR	N	OR (95% CI)*	P-value
Controls	152	---	727	---	---
Cases by number of years between blood draw and cancer diagnosis
All combined	25	1.00	240	1.95 (1.24, 3.07)	0.004
<4 years	13	1.00	69	1.13 (0.60, 2.14)	0.70
4+ years	12	1.00	171	2.85 (1.54, 5.28)	<0.001
8+ years	8	1.00	110	2.63 (1.24, 5.59)	0.01

^*Analysis includes 265 cases and 879 controls with known status on seropositivity of antibodies to H. pylori. Odds ratios (ORs) were derived from coefficient estimates of unconditional logistic regression models that included the following covariates: age, number of years of sample storage, neighborhood of residence at baseline, level of education (No formal schooling or primary school, junior middle school, senior high school, and college or above),number of alcoholic drinks per day (none, <2, 2–<4, and 4 or more), cigarette smoking (never, ever); OR, odds ratio;CI, confidence interval.