Helicobacter pylori infection and esophageal cancer risk: An updated meta-analysis

Table 2 Meta-analysis of the Helicobacter pylori infection on the risk of esophageal squamous cell carcinoma and esophageal adenocarcinoma

	Studies	P1	I2,2	Overall OR (95%CI)
Esophageal squamous cell carcinoma
Case/control (1961/5704)
All studies	16	< 0.01	74.50%	0.83 (0.63, 1.03)
Population-based studies	14	< 0.01	76.00%	0.79 (0.59, 1.00)
Clinical-based studies	2	0.86	< 0.01	1.49 (0.66, 2.31)
Eastern studies	8	< 0.01	79.50%	0.66 (0.43, 0.89)
Western studies	8	0.42	1.20%	1.02 (0.80, 1.25)3
Studies with matched controls	11	< 0.01	71.80%	0.90 (0.61, 1.20)
Studies without matched controls	5	< 0.01	82.90%	0.79 (0.46, 1.12)
Hp+ only definition as HpSe+	14	< 0.01	76.80%	0.81 (0.60, 1.02)
Adjusted results	11	< 0.01	80.50%	0.84 (0.56, 1.12)
CagA+vs Hp-	9	0.03	52.00%	0.97 (0.76, 1.24)
Eastern study	3	0.22	35.00%	0.77 (0.65, 0.92)3
Western studies	6	0.39	3.60%	1.26 (0.97, 1.63)3
Esophageal adenocarcinoma
Case/control (1330/4705)
All studies	15	0.131	29.9	0.59 (0.51, 0.68)
Population-based studies	8	0.106	40.9	0.62 (0.52, 0.73)
Clinical-based studies	7	0.319	14.5	0.53 (0.40, 0.68)
Eastern study	1	-	-	-
Western studies	14	0.128	31	0.60 (0.52, 0.68)
Studies with matched controls	10	0.139	33.6	0.62 (0.53, 0.72)
Studies without matched controls	5	0.333	12.7	0.49 (0.36, 0.66)
Hp+ definition as HpSe+	8	0.299	16.6	0.55 (0.45, 0.66)
Hp+ definition as His+	4	0.334	11.7	0.46 (0.33, 0.64)
Adjusted results	8	0.200	28.6	0.51 (0.40, 0.61)
CagA+vs Hp-	8	0.11	39.9	0.56 (0.45, 0.70)
Eastern study	0	-	-	-
Western studies	8	0.11	39.9	0.56 (0.45, 0.70)

¹P value for Q statistical in random effects model; ²Higgins I² statistic for heterogeneity in random effects model;

³The overall value synthesized by fixed effects model. HpSe⁺: Sero-positivity for antibodies to whole-cell; CagA⁺: Sero-positivity for antibodies to cytotoxin-associated gene-A.