Polymorphism of -765G > C COX-2 is a risk factor for gastric adenocarcinoma and peptic ulcer disease in addition to H pylori infection: A study from northern India

Table 1 Demography of the study populations and H pylori infection

Parameter	Gastric adenocarcinoma	Peptic ulcer disease	Non-ulcer dyspepsia	Overall
	(n = 62)	(n = 45)	(n = 241)	(348)
Age (yr)	56.60 ± 15.42	49.47 ± 17.22	43.75 ± 14.76	46.78 ± 15.96
Male:Female	47:15	31:14	138:103	216:132
H pylori infection1 (%)	35 (56.5)	36 (80)	133 (55.2)	204 (58.6)

¹Peptic ulcer disease vs non-ulcer dyspepsia: 80% vs 55.2%, P = 0.002; Gastric adenocarcinoma vs non-ulcer dyspepsia: 56.5% vs 55.2%, P = 0.858; Peptic ulcer disease vs gastric adenocarcinoma: 80% vs 56.5%, P = 0.01.

Table 2 Allelic distribution of COX-2 polymorphism in gastric adenocarcinoma, peptic ulcer disease and non-ulcer dyspepsia

COX-2 genotype	Gastric adenocarcinoma	Peptic ulcer disease	Non-ulcer dyspepsia
	(n = 62)	(n = 45)	(n = 241)
GG (%)	14 (22.6)	31 (68.9)	171 (71)
GC (%)	29 (46.8)	12 (26.7)	62 (25.7)
CC (%)	19 (30.6)	2 (4.4)	8 (3.3)
C carrier (%)1	48 (77.4)	14 (31.1)	70 (29)

¹Gastric adenocarcinoma vs non-ulcer dyspepsia: P < 0.001; Gastric adeno-carcinoma vs peptic ulcer disease: P < 0.001; Peptic ulcer disease vs non-ulcer dyspepsia: P = 0.74.

Table 3 H pylori infection and COX-2 polymorphism as risk for gastric adenocarcinoma

H pylori status	COX-2 genotype	Gastric adenocarcinoma (n = 62)	Non-ulcer dyspepsia (Controls, n = 241)	OR (95% CI)	P-value
HP-	GG	8	79	Referent
HP-	C carriers	19	29	7.06 (2.61-19.09)	< 0.001
HP+	GG	6	92	0.83 (0.26-2.59)	0.747
HP+	C carriers	29	41	7.83 (3.09-19.85)	< 0.001

HP-: H pylori negative; HP+: H pylori positive.

Table 4 H pylori infection and COX-2 polymorphism as risk for peptic ulcer disease

H pylori status	COX-2 genotype	Peptic ulcer disease (n = 45)	Non-ulcer dyspepsia (Controls, n = 241)	OR (95% CI)	P-value
HP-	GG	8	79	Referent
HP-	C carriers	1	29	0.86 (0.09-7.48)	0.89
HP+	GG	23	92	2.83 (1.18-6.73)	0.019
HP+	C carriers	13	41	5.65 (2.07-15.34)	< 0.001

HP-: H pylori negative; HP+: H pylori positive.

Table 5 C allele frequency and C carrier distribution in control populations from various countries

Country	Control	C allele	C carrier	Reference
	population (n)	Frequency (%)	distribution (%)
America
USA	228	21	37	27
USA (African American)	100	32	52	27
Europe
Portugal	210	22	38	34
Italy	864	28	50	31
UK	454	14	25	22
Poland	547	17	31	30
Australia
Australia	168	17	31	32
Asia
India	241	16	29	Present study
Singapore	1177	5	9	23
Japan	241	2	5	24
China	1270	2	4	19