Is Helicobacter pylori infection protective against esophageal cancer?

Table 2 Summary of meta-analyses regarding the association between Helicobacter pylori infection and esophageal cancer

Authors	Year of publication	Number of studies	Association of H. pylori infection with ESCC	Association of H. pylori infection with EAC
Gao et al[19]	2019	35	No significant association in the general population: OR 0.84 (95%CI: 0.64-1.09)/OR 0.74 (95%CI: 0.54-0.97); Inverse relationship in the Middle Eastern population: OR: 0.34 (95%CI: 0.22-0.52 or 0.26-0.44); Positive association with the North American population: OR: 1.83 (95%CI: 1.17-2.87)	Inverse relationship: OR 0.55 (95%CI: 0.43-0.70)/OR 0.23 (95%CI: 0.15-0.36)
Nie et al[20]	2014	28	No significant association with the general population: OR 1.16 (95%CI: 0.83-1.60); Inverse association with Asian population: OR 0.74 (95%CI: 0.57–0.97); Positive association with non-Asian population: OR 1.41 (95%CI: 1.02–1.94)	Inverse relationship: OR 0.57 (95%CI: 0.44-0.73)
Xie et al[21]	2013	27	No significant association in the general population: OR 0.83 (95%CI: 0.63-1.03); Inverse relationship with the East Asian population: OR 0.66 (95%CI: 0.43-0.89)	Inverse relationship: OR 0.59 (95%CI: 0.51-0.68)
Islami and Kamangar[22]	2008	19	No significant association: OR 1.10 (95%CI: 0.78-1.55)	Inverse relationship: OR 0.56 (95%CI: 0.46-0.68)
Zhuo et al[23]	2008	195	No significant association: OR 0.80 (95%CI: 0.45-1.43), Z = 0.75, P > 0.05	Inverse relationship: OR 0.58 (95%CI: 0.48-0.70), Z = 5.79, P < 0.01
Rokkas et al[24]	2007	72	No significant association: OR 0.85 (95%CI: 0.55-1.33), P = 0.48	Inverse relationship: OR 0.52 (95%CI: 0.37-0.73), P < 0.001

H. pylori: Helicobacter pylori; ESCC: Esophageal squamous cell carcinoma; EAC: Esophageal adenocarcinoma; OR: Odds ratio.