Association Between Infection and Colorectal Polyps: A Meta-Analysis of Observational Studies

Background: It has been suggested that () infection is associated with hypergastrinemia and proliferation of colorectal mucosa via direct stimulation, dysbiosis of the gut microbiome, and changes in the gut microbiome, all of which may lead to the formation of colorectal polyps. However, the consensus remains lacking regarding whether infection is independently associated with colorectal polyps and whether the association differs according to histological type of colorectal polyps. To summarize the current evidence regarding the relationship between infection and colorectal polyps, we conducted a meta-analysis of related observational studies according to the histological types of colorectal polyps.

Methods: Observational studies investigating the association between infection and colorectal polyps using multivariate analyses were included by search of PubMed, Embase, and Web of Science. A random-effects model was adopted to combine the results.

Results: Seventeen studies that include 322,395 participants were analyzed. It was shown that infection was independently associated with overall colorectal polyps (odds ratio [OR]: 1.67, 95% CI: 1.24-2.24, < 0.001; = 73%). According to the histological type of colorectal polyps, infection was independently associated with adenomatous polyps (APs; OR: 1.71, 95% CI: 1.47-1.99, < 0.001; = 86%), advanced APs (OR: 2.06, 95% CI: 1.56-2.73, < 0.001; = 0%), and hyperplastic polyps (HPs; OR: 1.54, 95% CI: 1.02-2.30, = 0.04; = 78%). Evidence based on only one study showed that infection was not associated with sessile serrated polyps (SSPs; OR: 1.00, 95% CI: 0.93-1.07, = 0.99).

Conclusions: Current evidence from case-control and cross-sectional studies suggested that infection was independently associated with colorectal APs, advanced APs, and HPs, but not with SSPs. These findings suggested infection may be a possible risk factor of colorectal polyp, which is important for the prevention of colorectal polyp in the adult population.