Table 2

The association between H. pylori infection and risk of gastric adenocarcinoma (adjusted for sex, age, and hospital)

Type of gastric cancer	Cases	All included controls			Controls with normal mucosa
Type of gastric cancer		(no.)	(no.)	OR (95% CI)^a	(no.)	OR (95% CI)^a
All gastric adenocarcinoma
H. p neg^b	15	111	1 (Reference)	43	1 (Reference)
H. p pos	57	213	2.1 (1.1–3.9)	71	2.1 (1.0–4.6)
Noncardia cancer
H. p neg	12	111	1 (Reference)	43	1 (Reference)
H. p pos	52	213	2.4 (1.2–4.8)	71	2.6 (1.1–5.8)
Cardia cancer
H. p neg	3	111	1 (Reference)	43	1 (Reference)
H. p pos	5	213	0.7 (0.2–3.2)	71	0.7 (0.1–3.4)
Intestinal type
H. p neg	9	111	1 (Reference)	43	1 (Reference)
H. p pos	31	213	1.9 (0.9–4.3)	71	2.1 (0.8–5.3)
Diffuse type
H. p neg	5	111	1 (Reference)	43	1 (Reference)
H. p pos	20	213	2.2 (0.8–6.2)	71	2.1 (0.7–6.5)

^a Same subset of controls are used as reference for all groups of gastric cancer.
^b H. p neg, H. pylori negative; H. p pos, H. pylori positive.