Summary of findings 1. H. pylori eradication therapy compared to control for the prevention of gastric neoplasia in healthy asymptomatic infected individuals.
| H. pylorieradication therapy compared to control for the prevention of gastric neoplasia in healthy asymptomatic infected individuals | ||||||
| Patient or population: healthy asymptomatic H. pylori‐infected individuals Settings: general population1 Intervention:H. pylori eradication therapy to prevent subsequent gastric cancer 2 Comparison: control | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Control | H. pylorieradication therapy to prevent subsequent gastric cancer | |||||
| Incidence of gastric cancer ‐ modified ITT analysis Histological examination Follow‐up: 4 to 22 years | 30 per 1000 | 16 per 1000 (12 to 22) | RR 0.54 (0.40 to 0.72) | 8323 (7 studies) | ⊕⊕⊕⊝ moderate3,4,5,6 | Number need to treat to benefit was 72 (95% CI 55 to 118) |
|
Death from gastric cancer ‐ modified ITT analysis Follow up: 7‐22 years |
19 per 1000 | 11 per 1000 (7 to 17) | RR 0.61 (0.40 to 0.92) | 6301 (4 studies) | ⊕⊕⊕⊝ moderate4,6,7 | Number need to treat to benefit was 137 (95% CI 89 to 667) |
| Death from all causes ‐ modified ITT analysis | 92 per 1000 | 89 per 1000 (78 to 103) | RR 0.97 (0.85 to 1.12) | 7079 (5 studies) | ⊕⊕⊕⊝ moderate4,6,7 | |
|
Incidence of oesophageal squamous cell carcinoma ‐ modified ITT analysis Follow up: 7‐22 years |
7 per 1000 | 8 per 1000 (4 to 17) | RR 1.22 (0.59 to 2.54) | 3888 (2 study) | ⊕⊕⊕⊝ moderate8 | |
| Adverse events | See comment | See comment | Not estimable | 0 (0) | See comment | Adverse events were poorly reported across the studies and could not be summarised. |
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; ITT: intention‐to‐treat; RR: risk ratio | ||||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
1 As all but one study was conducted in East Asia, it is not possible to assess the effect of searching for and eradicating H. pylori in Western populations. 2 Modified ITT analysis. 3 The quality of evidence was downgraded from high to moderate due to serious risk of bias: Fourtrials were at low risk of bias, one trial was at unclear risk, and two trials were at high risk of bias. In addition, because of the factorial design of some of the trials, it is difficult to determine whether the reduction in relative risk of subsequent gastric cancer was due to H. pylori eradication therapy alone. The eradication regimens used varied considerably between the individual trials, although this reflects the fact that several of these studies were designed before the widespread adoption of proton pump inhibitor triple therapy, which was first described in 1994, as the gold standard for H. pylori eradication. 4 No significant heterogeneity was seen between studies. 5 The beneficial effect seemed to be more pronounced in the two studies that co‐administered antioxidants and vitamins to participants, but it should be noted that one of these contained the majority of gastric cancers and had the longest duration of follow‐up. There was no significant benefit of H. pylori eradication therapy in preventing subsequent occurrence of gastric cancer when only those participants either with or without preneoplastic lesions at baseline were considered in the analysis. There were no significant subgroup differences. 6 Funnel plots were not produced, as there were less than 10 studies included in the analyses. 7 The quality of evidence was downgraded from high to moderate due to serious risk of bias: one trial was at high risk of bias. 8 Only two studies were available for this outcome, with wide 95% CI.