Published online May 7, 2015. doi: 10.3748/wjg.v21.i17.5407
Peer-review started: August 14, 2014
First decision: October 14, 2014
Revised: October 31, 2014
Accepted: December 8, 2014
Article in press: December 8, 2014
Published online: May 7, 2015
Processing time: 292 Days and 12 Hours
AIM: To investigate whether Helicobacter pylori (H. pylori) infection is associated with glycemic control and whether hyperglycemia is modified by eradication therapy.
METHODS: The databases of PubMed, Cochrane Library, Chinese BioMedicine Web Base and Chinese Science and Technology Journals were searched from inception to June 2014. Studies examining the association between H. pylori infection and glycemic control and⁄or the effect of eradication treatment on glycemic control in diabetic humans were eligible for inclusion. Meta-analyses were conducted using the Review Manager software version 5.2. The outcome measures are presented as weighed mean differences (WMDs) with 95% confidence intervals (CIs). Statistical heterogeneity was assessed by the Cochran Q test and the I2 statistic.
RESULTS: A total of 21 relevant publications were identified. A meta-analysis of 11 studies with 513 patients with diabetes mellitus (DM) showed significantly lower glycosylated hemoglobin (HbA1c) levels in the H. pylori-negative than H. pylori-positive DM participants (WMD = 0.43, 95%CI: 0.07-0.79; P = 0.02). In children and adolescents with type 1 DM (T1DM), there was a positive association between H. pylori infection and HbA1c level (WMD = 0.35, 95%CI: 0.05-0.64; P = 0.02), but there was no difference in those with type 2 DM (T2DM, WMD = 0.51, 95%CI: -0.63-1.65; P = 0.38). A meta-analysis of six studies with 325 T2DM participants showed a significant difference in the fasting plasma glucose levels between H. pylori-positive and H. pylori-negative participants (WMD = 1.20, 95%CI: 0.17-2.23; P = 0.02). Eradication of H. pylori did not improve glycemic control in the T2DM participants in a three-month follow-up period (HbA1c decrease: WMD = -0.03, 95%CI = -0.14-0.08; P = 0.57; fasting plasma glucose decrease: WMD = -0.06, 95%CI: -0.36-0.23; P = 0.68). Glycemic control was significantly better in T1DM participants who were not reinfected than in those who were reinfected (HbA1c: WMD = 0.72, 95%CI: 0.32-1.13: P = 0.00).
CONCLUSION: H. pylori infection is associated with poorer glycemic control in T1DM patients, but eradication may not improve glycemic control in DM in a short-term follow-up period.
Core tip: Infection with Helicobacter pylori (H. pylori) has been suggested to play a pathogenic role in diabetes mellitus. The association between H. pylori and glycemic control in diabetics remains controversial. Our systematic review suggests a positive association between H. pylori and glycemic control in diabetics, especially in patients with type 1. While a short-term follow-up analysis demonstrated that H. pylori eradication does not improve glycemic control in diabetics, the long-term effects of eradication treatment remain unknown. Thus, the question remains as to whether the indication for H. pylori eradication in diabetic patients should be extended.