Home About us Editorial board Ahead of print Current issue Search Archives Submit article Instructions Subscribe Contacts Login 

 Table of Contents  
ORIGINAL ARTICLE
Year : 2014  |  Volume : 10  |  Issue : 8  |  Page : 263-266

Association between Helicobacter pylori infection and colorectal neoplasm risk: A meta-analysis Based on East Asian population


1 Department of Clinical Laboratory, Peking University People's Hospital, 100044 Beijing, China
2 Department of Clinical Laboratory, Beijing Chuiyangliu Hospital, 100022 Beijing, China

Date of Web Publication17-Feb-2015

Correspondence Address:
Yu Guo
Department of Clinical Laboratory, Peking University People's Hospital, Xizhimen South Avenue No. 11, 100044 Beijing
China
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0973-1482.151482

Rights and Permissions
 > Abstract 

Objective: The association between Helicobacter pylori (HP) infection and colorectal neoplasm risk was not clear. The aim of this study was to evaluate whether HP infection can increase the risk of developing colorectal neoplasm by meta-analysis.
Materials and Methods: A detailed literature search was performed on Medline, PubMed, Web of Science, and China National Knowledge Infrastructure for related research publications written in English and/or Chinese. The relevant case-control or cohort studies reporting an association between HP infection and colorectal neoplasm risk were screened and included in this meta-analysis. The association between HP infection and colorectal neoplasm risk was expressed by odds ratio (OR) and its 95% confidence interval (CI). The heterogeneity among the included articles was assessed by I 2 test, and the pooled OR was calculated by fixed effect model in case of no significant heterogeneity otherwise random effect model was employed. All the statistical analyses were done by STATA-11.0 and MetaAnalyst Beta 3.13 software.
Results: Finally, a total of 2081 colorectal neoplasm patients and 5598 healthy controls from nine eligible studies were included in this meta-analysis. The pooled OR for the association between HP infection and colorectal neoplasm risk was 0.18 with its 95% CI of 0.99-1.40, (P > 0.05). We further divided the colorectal neoplasm into the hyperplastic polyps, adenomas and colorectal cancer sub-groups according to colorectal neoplasm types. The pooled ORs and their 95% CIs were OR Hyperplastic_polyps = 0.72, 95% CI: 0.44-1.18, (P > 0.05), OR Adenomas = 1.83, 95% CI: 1.35-2.51, (P < 0.01), OR Colorectal_cancer = 1.08, 95% CI: 0.89-1.68 (P > 0.05). For different region sub-groups, the pooled ORs and 95% CIs were OR South_Korea = 1.18, 95% CI: 0.84-1.66, (P > 0.05), OR China = 0.78, 95% CI: 0.53-1.13, (P > 0.05), OR Taiwan = 1.06, 95% CI: 0.69-1.62, (P > 0.05), OR Japan = 1.33, 95% CI: 1.07-1.65, (P < 0.05) for South Korea, China main land, Taiwan and Japanese.
Conclusion: In general, no statistical association between HP infection and colorectal neoplasm risk was found in this meta-analysis. But, HP infection may increase the risk of developing colorectal adenomas.

Keywords: Colorectal neoplasm, Helicobacter pylori infection, meta-analysis, risk


How to cite this article:
Guo Y, Li HY. Association between Helicobacter pylori infection and colorectal neoplasm risk: A meta-analysis Based on East Asian population. J Can Res Ther 2014;10, Suppl S4:263-6

How to cite this URL:
Guo Y, Li HY. Association between Helicobacter pylori infection and colorectal neoplasm risk: A meta-analysis Based on East Asian population. J Can Res Ther [serial online] 2014 [cited 2020 Oct 25];10:263-6. Available from: https://www.cancerjournal.net/text.asp?2014/10/8/263/151482


 > Introduction Top


Colorectal carcinoma is one of the major causes of cancer-related morbidity and mortality. It is the third most common malignancy and fourth most common cause of cancer-related death worldwide. [1] With the development of cytobiology and molecular biology, more and more mechanism was known for the carcinogenesis of colorectal cancer such as inflammatory bowel disease, positive family history, and genetic mutations. As everybody knows that the Helicobacter pylori (HP) infection can cause chronic gastritis, peptic ulcer disease, and gastric malignancy. [1],[2],[3] And recently, epidemiological studies demonstrated that patients with HP infection prone to have colorectal neoplasm. [4] Some studies indicated that the HP infection may increase the risk of colorectal neoplasm. [4],[5],[6] But other studies showed that there was no association between HP infection and colorectal neoplasm risk. [7] Because of the small number cases and different study design for the individual study, the conclusion for the relationship between HP infection and colorectal neoplasm was limited and lack of power. Thereby, we used the published data based on East Asian population to perform a meta-analysis in order to further evaluate this question.


 > Materials and methods Top


Searching strategy

A literature search was performed to identify case control or cohort studies evaluating the association between HP infection and colorectal neoplasm risk. We searched the database of Medline, Embase, and the Cochrane Central Register of Controlled Trials (Issue 4, 2014) and China National Knowledge Infrastructure. The search terms used included: "HP" "colorectal neoplasm," "colorectal adenoma," "colorectal cancer," "colorectal carcinoma." The final set of full extent review of the selected studies included cross checked references and direct communication with the corresponding authors when the article was not available in full-length on-line. [8]

Inclusion and exclusion criteria

The inclusion criteria were: (a) Case-control or cohort study; (b) published in English or Chinese; (c) patients included in the original studies belong to East Asian ethnicity; (d) enough data for calculation of odds ratio (OR) and its 95% confidence intervals (CIs) can be drawn from the included studies. The exclusion criteria were: (a) Duplicated publications; (b) not enough data can be extract from the original study; (c) language published other than English or Chinese; (d) patients included in the original study were not East Asian ethnicity; (e) review or case report.

Data extraction

Data were extracted from each study by two reviewers independently. The following information was collected in a predefined form: First and corresponding author's name, year of publication, country of origin, ethnicity, total number of cases in each group, number of HP+/HP− subjects in the case and control groups, HP array methods. If a disagreement was found in the procedure of data extraction, discussion or consulting for another reviewer was employed.

Statistical analysis

All statistical analyses were performed using STATA/SE 11.0 (http:// Stata Corporation, College Station, TX) and MetaAanlyst 3.13 ( http://tuftscaes.org/meta_analyst ). The pooled ORs and its 95% CIs were calculated using either the Mantel-Haenszel formula (fixed-effect model) or the Dersimonian-Laird formula (random-effect model). A fixed-effect model was used when heterogeneity was not detected (P > 0.1); otherwise, a random-effect model was employed. For quantitative analysis, OR and its 95% CIs was used to evaluate the association between HP infection and colorectal neoplasm risk. Sensitivity analysis was also performed to assess the contribution of each study to the final results of the meta-analysis. [9] The Begg's funnel plot and Egger's test were used to evaluate the possible publication bias.


 > Results Top


General information of the included articles

Nine studies with 2081 colorectal neoplasm patients and 5598 healthy controls were included in this meta-analysis. The sample size ranges from 346 to 2701. Of the nine included studies, four from Japan, three from Korea, one from China mainland, and one from Taiwan. Three studies using the 13 C urea breath test for detection of HP and other six using the serological immunoglobulin G array for HP detection. The median HP positive rate in colorectal neoplasm was 0.67 (0.55-0.84) and 0.65 (0.56-0.79) in healthy controls. The main information of the nine included articles were demonstrated in [Table 1].
Table 1: Main characteristics of the included studies in this meta-analysis

Click here to view


Meta-analysis

Before pooling the OR, we first test the heterogeneity among the included nine studies. The I2 was 51.8% which indicating significant heterogeneity existing among the included studies. The pooled OR for evaluating the association between HP infection and colorectal neoplasm risk was calculated by random effect model. The pooled OR was 0.18 with its 95% CI of 0.99-1.40, (P > 0.05) [Figure 1] which indicates that there was no significant association between HP infection and colorectal neoplasm risk.
Figure 1: Forest plot for evaluation of the Helicobacter Pylori infection and colorectal neoplasm risk

Click here to view


Sub-group analysis

Because of the significant heterogeneity among the included articles, we further pooled the sub-group ORs according to neoplasm types and areas [Table 2]. In the sub-group analysis, we found that the HP infection was associated with the risk of colorectal adenoma (OR = 1.83, P < 0.01). HP infection can increase the risk of colorectal adenoma risk by 83%. And for Japanese population, a significant association of HP infection and colorectal neoplasm risk was also observed (OR = 1.33, P < 0.05).
Table 2: Sub - group analysis of the relationship between HP infection and colorectal neoplasm risk

Click here to view


Sensitivity analysis for the each included studies

The sensitivity analysis was employed by omitting each included study. The P value changed from > 0.05 to < 0.05 when omitting the single study of Song et al. and Bae et al. [Figure 2]. This result indicated that the pooled OR was sensitive to the single study of Song et al. and Bae et al.
Figure 2: The sensitivity analysis for this meta-analysis

Click here to view


Publication bias analysis

Funnel plot of Bgg's test and Egger's line regression test were used to assess the publication bias, [15] and it provided evidence that there was no publication bias among studies regarding HP infection and colorectal neoplasm risk (t = −0.26, P = 0.80) [Figure 3].
Figure 3: The funnel plot for evaluation publication bias

Click here to view



 > Discussion Top


In the previously study, there were two meta-analyses reporting the association between HP infection and colorectal neoplasm risk. One was performed by Wu et al. [16] and the other by Rokkas et al. [17] After carefully reading the previously published two meta-analysis about the association between HP infection and colorectal neoplasm risk, we found that there were some limitations in the previous studies. In Rokkas' study, they found that the HP infection can increase the colorectal cancer and polyps by 30% and 50%, respectively. And in Wu' study, the OR for the association between HP infection and colorectal adenoma and colorectal cancer were 1.66 and 1.39 which indicated that the HP infection can significant increase the risk of developing colorectal adenoma and colorectal cancer. But in their meta-analysis, they included all the population of any ethnicity which could increase the clinical heterogeneity.

In our present meta-analysis, we only included the original study reporting the population of East Asian ethnicity and made detailed sub-group analysis according to neoplasm types and areas. A total of 2081 colorectal neoplasm patients and 5598 healthy controls from nine eligible studies were included in our meta-analysis. The pooled OR for the association between HP infection and colorectal neoplasm risk was 0.18 with its 95% CI of 0.99-1.40, (P > 0.05). In general, no statistical association between HP infection and colorectal neoplasm risk was found in our meta-analysis. This result was different from Rokkas and Wu. We believe the reason for the different results due to different population included in the meta-analysis. In Rokkas et al. and Wu et al. meta-analysis, [16],[17] they included all ethnic population including East Asian, Caucasian, and mixed population. In our meta-analysis, we only included East Asian population and added newly published studies about HP infection and colorectal neoplasm risk. The different population included in a separate meta-analysis made the results, not in accordance with each other.

We further divided the colorectal neoplasm into the hyperplastic polyps, adenomas, and colorectal cancer sub-groups according to colorectal neoplasm types. And the pooled OR and their 95% CI were OR Hyperplastic_polyps = 0.72, 95% CI: 0.44-1.18, (P > 0.05), OR Adenomas = 1.83, 95% CI: 1.35-2.51, (P < 0.01), OR Colorectal_cancer = 1.08, 95% CI: 0.89-1.68 (P > 0.05). We found that the HP infection significantly increases the risk of colorectal adenoma (P < 0.05), but not for colorectal hyperplastic polyps (P > 0.05) and colorectal cancer (P > 0.05). For different region sub-groups, the pooled OR and 95% CI were OR South_Korea = 1.18, 95% CI: 0.84-1.66, (P > 0.05), OR China = 0.78, 95% CI: 0.53-1.13, (P > 0.05), OR Taiwan = 1.06, 95% CI: 0.69-1.62, (P > 0.05), OR Japan = 1.33, 95% CI: 1.07-1.65, (P < 0.05) for South Korea, China main land, Taiwan, and Japanese. HP infection can increase the risk of colorectal neoplasm in Japanese population. The results of the sub-groups were quite different from each other. And this may due to the clinical heterogeneity among the included studies.

In our present meta-analysis, no statistical association between HP infection and colorectal neoplasm risk was found in this meta-analysis. But, HP infection may increase the risk of developing colorectal adenomas. And increase the risk of developing of colorectal neoplasm in Japanese population. But due to significant statistical heterogeneity among the studies and results sensitivity to a single included paper, the conclusion of this meta-analysis was limited and need to be further confirmed by more high quality case control or cohort studies.

 
 > References Top

1.
Tenesa A, Dunlop MG. New insights into the aetiology of colorectal cancer from genome-wide association studies. Nat Rev Genet 2009;10:353-8.  Back to cited text no. 1
    
2.
Castaño-Milla C, Chaparro M, Gisbert JP. Systematic review with meta-analysis: The declining risk of colorectal cancer in ulcerative colitis. Aliment Pharmacol Ther 2014;39:645-59.  Back to cited text no. 2
    
3.
Lytras T, Nikolopoulos G, Bonovas S. Statins and the risk of colorectal cancer: An updated systematic review and meta-analysis of 40 studies. World J Gastroenterol 2014;20:1858-70.  Back to cited text no. 3
    
4.
Hong SN, Lee SM, Kim JH, Lee TY, Kim JH, Choe WH, et al. Helicobacter pylori infection increases the risk of colorectal adenomas: Cross-sectional study and meta-analysis. Dig Dis Sci 2012;57:2184-94.  Back to cited text no. 4
    
5.
Inoue I, Mukoubayashi C, Yoshimura N, Niwa T, Deguchi H, Watanabe M, et al. Elevated risk of colorectal adenoma with Helicobacter pylori-related chronic gastritis: A population-based case-control study. Int J Cancer 2011;129:2704-11.  Back to cited text no. 5
    
6.
Nam KW, Baeg MK, Kwon JH, Cho SH, Na SJ, Choi MG. Helicobacter pylori seropositivity is positively associated with colorectal neoplasms. Korean J Gastroenterol 2013;61:259-64.  Back to cited text no. 6
    
7.
Machida-Montani A, Sasazuki S, Inoue M, Natsukawa S, Shaura K, Koizumi Y, et al. Atrophic gastritis, Helicobacter pylori, and colorectal cancer risk: A case-control study. Helicobacter 2007;12:328-32.  Back to cited text no. 7
    
8.
Leal YA, Flores LL, García-Cortés LB, Cedillo-Rivera R, Torres J. Antibody-based detection tests for the diagnosis of Helicobacter pylori infection in children: A meta-analysis. PLoS One 2008;3:e3751.  Back to cited text no. 8
    
9.
Gu J, Wen Y, Zhu S, Hua F, Zhao H, Xu H, et al. Association between P (16INK4a) promoter methylation and non-small cell lung cancer: A meta-analysis. PLoS One 2013;8:e60107.  Back to cited text no. 9
    
10.
Fujimori S, Kishida T, Kobayashi T, Sekita Y, Seo T, Nagata K, et al. Helicobacter pylori infection increases the risk of colorectal adenoma and adenocarcinoma, especially in women. J Gastroenterol 2005;40:887-93.  Back to cited text no. 10
    
11.
Mizuno S, Morita Y, Inui T, Asakawa A, Ueno N, Ando T, et al. Helicobacter pylori infection is associated with colon adenomatous polyps detected by high-resolution colonoscopy. Int J Cancer 2005;117:1058-9.  Back to cited text no. 11
    
12.
Liou JM, Lin JW, Huang SP, Lin JT, Wu MS. Helicobacter pylori infection is not associated with increased risk of colorectal polyps in Taiwanese. Int J Cancer 2006;119:1999-2000.  Back to cited text no. 12
[PUBMED]    
13.
Song YF, Zhang Y, Cui BB, Tian SL, Li Y, Dong XS, et al. A case control study on the relationship between colorectal cancer and Helicobacter pylori Infection and other factors. J Mod Oncol 2007;15:1003-6.  Back to cited text no. 13
    
14.
Bae RC, Jeon SW, Cho HJ, Jung MK, Kweon YO, Kim SK. Gastric dysplasia may be an independent risk factor of an advanced colorectal neoplasm. World J Gastroenterol 2009;15:5722-6.  Back to cited text no. 14
    
15.
Mavridis D, Salanti G. How to assess publication bias: Funnel plot, trim-and-fill method and selection models. Evid Based Ment Health 2014;17:30.  Back to cited text no. 15
    
16.
Wu Q, Yang ZP, Xu P, Gao LC, Fan DM. Association between Helicobacter pylori infection and the risk of colorectal neoplasia: A systematic review and meta-analysis. Colorectal Dis 2013;15:e352-64.  Back to cited text no. 16
    
17.
Rokkas T, Sechopoulos P, Pistiolas D, Kothonas F, Margantinis G, Koukoulis G. The relationship of Helicobacter pylori infection and colon neoplasia, on the basis of meta-analysis. Eur J Gastroenterol Hepatol 2013;25:1286-94.  Back to cited text no. 17
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

  [Table 1], [Table 2]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

  >Abstract>Introduction>Materials and me...>Results>Discussion>Article Figures>Article Tables
  In this article
>References

 Article Access Statistics
    Viewed2116    
    Printed56    
    Emailed0    
    PDF Downloaded152    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]