Background Gastroesophageal reflux disease (GERD), which leads to acid reflux into the esophagus, is a common gastrointestinal disorder. Several studies have shown the prevalence of GERD in Iranian population, but their evidence is contradictory. Therefore, the present study was conducted to investigate the epidemiology of GERD in Iran. Methods The entire steps of this systematic review and meta-analysis were based on the MOOSE protocol, and the results were reported accordance with the PRISMA guideline. This review is registered on PROSPERO (registration number: CRD42020142861). To find potentially relevant published articles, comprehensive search was done on international online databases Scopus, Science Direct, EMBASE, PubMed/Medline, CINAHL, EBSCO, Cochrane Library, Web of Science, Iranian online databases and the Google Scholar search engine in June 2019. Cochran test and I2 index were used to assess the heterogeneity of the studies. Data were analyzed using Comprehensive Meta-Analysis software ver. 2. The significance level of the test was considered to be P <  0.05. Results The daily, weekly, monthly, and overall prevalence of GERD symptoms in Iranian population was 5.64% (95%CI [confidence interval]: 3.77–8.35%; N = 66,398), 12.50% (95%CI: 9.63–16.08%; N = 110,388), 18.62% (95%CI: 12.90–26.12%; N = 70,749) and 43.07% (95%CI: 35.00–51.53%; N = 73,189), respectively. The daily, weekly, monthly, and overall prevalence of heartburn in Iranian population was 2.46% (95%CI: 0.93–6.39%; N = 18,774), 9.52% (95%CI: 6.16–14.41%; N = 54,125), 8.19% (95%CI: 2.42–24.30%; N = 19,363) and 23.20% (95%CI: 13.56–36.79%; N = 26,543), respectively. The daily, weekly, monthly, and overall prevalence of regurgitation in Iranian population was 4.00% (95%CI: 1.88–8.32%; N = 18,774), 9.79% (95%CI: 5.99–15.60%; N = 41,140), 13.76% (95%CI: 6.18–44.31%; N = 19,363) and 36.53% (95%CI: 19.30–58.08%; N = 21,174), respectively. The sensitivity analysis for prevalence of all types GERD, heartburn and regurgitation symptoms by removing a study showed that the overall estimate is still robust. Conclusion The present meta-analysis provides comprehensive and useful information on the epidemiology of GERD in Iran for policy-makers and health care providers. This study showed a high prevalence of GERD in Iran. Therefore, effective measures on GERD-related factors such as lifestyle can be among the health policies of Iran.

Background: Dyspepsia is a highly prevalent gastrointestinal problem. The present study was carried out to assess the prevalence of dyspepsia in Iran. Methods: The present study was registered at PROSPERO with the code CRD42019148610. It was carried out based on MOOSE and reporting was performed according to the PRISMA protocol. Systematic search of the literature was performed in July 2019 on international databases of PubMed/Medline, Web of Science (ISI), Cochrane Library, EBSCO, CINAHL, EMBASE, Scopus, Science Direct, and local databases as well as the Google Scholar search engine. Heterogeneity was evaluated using I 2 and Chi-square tests. All analyses were done using Comprehensive Meta-Analysis software. Results: Overall, 14 studies with a sample size of 54,118 subjects entered in this meta-analysis. The prevalence of dyspepsia in Iran was 14.6% (95% CI: 9.6-21.7). Large heterogeneity was detected among studies (I 2 = 99.62%, P < 0.001). The prevalence of dysmotility-like, ulcer-like, and unspecified dyspepsia was estimated to be 9.7% (95% CI: 4.9-18.4), 12.1% (95% CI: 5.2-25.7) and 17.0% (95% CI: 7.8-33.4), respectively. The prevalence of dyspepsia in Iranian men and women was found at 11.1% (95%

Introduction : Gastroesophageal reflux disease (GERD), which leads to acid reflux into the esophagus, is a common gastrointestinal disorder. Several studies have shown the prevalence of GERD in Iranian population, but their evidence is contradictory. Therefore, the present study was conducted to investigate the epidemiology of GERD in Iran. Methods: The entire steps of this systematic review and meta-analysis were based on the MOOSE protocol, and the results were accordance with the PRISMA guideline. To find potentially relevant published articles, comprehensive search was done on international online databases Scopus, Science Direct, EMBASE, PubMed/Medline, CINAHL, EBSCO, Cochrane Library (Cochrane Database of Systematic Reviews - CDSR), Web of Science (ISI) and Iranian online databases IranDoc, (SID), Magiran, RICST, Iranian National Library, and Barakat Knowledge Network System and the Google Scholar search engine in June 2019. Cochran test and I 2 index were used to assess the heterogeneity of the studies. Data were analyzed using Comprehensive Meta-Analysis (CMA) software. Results: The daily, weekly, monthly, and overall prevalence of GERD symptoms in Iranian population was 5.64% (95%CI [confidence interval]: 3.77%-8.35%; N=66,398), 12.50% (95%CI: 9.63%-16.08%; N=110,388), 18.62% (95%CI: 12.90%-26.12%; N= 70,749) and 43.07% (95%CI: 35.00%-51.53%; N=73,189), respectively. The daily, weekly, monthly, and overall prevalence of heartburn in Iranian population was 2.46% (95%CI: 0.93%-6.39%; N=18,774), 9.52% (95%CI: 6.16%-14.41%; N=54,125), 8.19% (95%CI: 2.42%-24.30%; N=19,363) and 23.20% (95%CI: 13.56%-36.79%; N=26,543), respectively. The daily, weekly, monthly, and overall prevalence of regurgitation in Iranian population was 4.00% (95%CI: 1.88%-8.32%; N=18,774), 9.79% (95%CI: 5.99%-15.60%; N=41,140), 13.76% (95%CI: 6.18%-44.31%; N=19,363) and 36.53% (95%CI: 19.30%-58.08%; N=21,174), respectively. Conclusion: The present meta-analysis provides comprehensive and useful information on the epidemiology of GERD in Iran for policy-makers and health care providers. This study showed a high prevalence of GERD in Iran. Therefore, effective measures on GERD-related factors such as lifestyle can be among the health policies of Iran.