Helicobacter pylori infection increases the risk of developing preeclampsia: A meta-analysis of observational studies

Causal associations between Helicobacter pylori infection and pregnancy and neonatal outcomes: a two-sample Mendelian randomization study

Background

Observational studies have reported that Helicobacter pylori (H. pylori) infection is associated with a series of pregnancy and neonatal outcomes. However, the results have been inconsistent, and the causal effect is unknown.

Methods

A two-sample Mendelian randomization (MR) study was performed using summary-level statistics for anti-H. pylori IgG levels from the Avon Longitudinal Study of Parents and Children Cohort. Outcome data for pregnancy (miscarriage, preeclampsia-eclampsia, gestational diabetes mellitus, placental abruption, premature rupture of membranes, postpartum hemorrhage) and neonates (birthweight, gestational age, and preterm birth) were sourced from genome-wide association meta-analysis as well as the FinnGen and Early Growth Genetics Consortium. Causal estimates were calculated by five methods including inverse variance weighted (IVW). The heterogeneity of instrumental variables was quantified by Cochran's Q test, while sensitivity analyses were performed via MR-Egger, MR-PRESSO, and leave-one-out tests.

Results

IVW estimates suggested that genetically predicted anti-H. pylori IgG levels were significantly associated with increased risks of preeclampsia-eclampsia (odds ratio [OR] = 1.12, 95% confidence interval [CI] 1.01-1.24, P = 0.026) and premature rupture of membranes (OR = 1.17, 95% CI 1.05-1.30, P = 0.004). Similar results were obtained for preeclampsia-eclampsia from the MR-Egger method (OR = 1.32, 95% CI 1.06-1.64, P = 0.027) and for premature rupture of membranes from the weighted median method (OR = 1.22, 95% CI 1.06-1.41, P = 0.006). No significant causal effects were found for other outcomes. There was no obvious heterogeneity and horizontal pleiotropy across the MR analysis.

Conclusion

Our two-sample MR study demonstrated a causal relationship of H. pylori infection with preeclampsia-eclampsia and premature rupture of membranes. The findings confirm the epidemiological evidence on the adverse impact of H. pylori in pregnancy. Further studies are needed to elucidate the pathophysiological mechanisms and assess the effectiveness of pre-pregnancy screening and preventive eradication.

The eNOS-G894T genetic polymorphism and risk of preeclampsia: A case-control study, an updated meta-analysis, and a bioinformatic assay

OBJECTIVES

Preeclampsia (PE) is a leading cause of maternal death worldwide and involves vascular endothelial dysfunction. The aim of this study was to investigate the association of the G894T polymorphism in the endothelial nitric oxide synthase (eNOS) gene and the risk of preeclampsia in a case-control design in an Iranian population, which was followed by a meta-analysis and an in silico approach.

METHODS

In the case-control study, 300 people including 135 pregnant women with preeclampsia and 165 healthy pregnant women were included. The genotype of G894T polymorphism was determined by the PCR-RFLP method. We searched authoritative scientific databases to find eligible studies for meta-analysis. The odds ratio with a 95% confidence interval was estimated to find the strength of the association of the mentioned polymorphism with the risk of preeclampsia. In addition, the effect of G894T transversion on eNOS gene function was evaluated by some bioinformatics tools.

RESULTS

Our case-control data showed that the G894T polymorphism is associated with an increased risk of preeclampsia. In the meta-analysis, 33 eligible studies were included, and the results showed that the G894T polymorphism is associated with an increased risk of preeclampsia in the overall analysis and some stratified analyses. In addition, the structural analysis showed that the G894T variant can affect the splicing process as well as the protein stability.

CONCLUSIONS

Based on the results, the aforementioned polymorphism may be a risk factor for preeclampsia and could be considered a potential molecular biomarker for screening susceptible individuals.

Pregnancy outcomes among women with peptic ulcer disease

Background Little is known about the impact of peptic ulcer disease (PUD) on pregnancy. Our objective was to evaluate the effect of PUD on pregnancy and newborn outcomes. Methods A retrospective cohort study was carried out using the Healthcare Cost and Utilization Project (HCUP)-National Inpatient Sample (NIS) from the United States. The cohort consisted of all births that took place from 1999 to 2015. PUD was classified on the basis of the International Classification of Diseases-Ninth Revision (ICD-9) coding. Multivariate logistic regression was used to evaluate the adjusted effect of PUD on maternal and neonatal outcomes. Results Of the 13,792,544 births in this cohort, 1005 were to women with PUD (7/100,000 births). Between 1999 and 2015, prevalence of PUD in pregnancy increased from 4/100,000 to 11/100,000, respectively. Women with PUD were more commonly older and more likely to have comorbid illnesses. Women with PUD were at greater risk of preeclampsia [odds ratio (OR) 2.11, 95% confidence interval (CI) 1.67-2.66], preterm premature rupture of membranes (PPROM; OR 2.16, 95% CI 1.30-3.59), cesarean delivery (OR 1.60, 95% CI 1.40-1.82), venous thromboembolism (OR 3.77, 95% CI 2.08-6.85) and maternal death (OR 24.50, 95% CI 10.12-59.32). Births to women with PUD were at increased risk of intrauterine growth restriction (IUGR; OR 1.54, 95% CI 1.11-2.14), preterm birth (OR 1.84, 95% CI 1.54-2.21), intrauterine fetal death (OR 2.18, 95% CI 1.35-3.52) and congenital anomalies (OR 2.69, 95% CI 1.59-4.56). Conclusion The prevalence of PUD in pregnancy has risen over the last several years. PUD in pregnancy should be considered a high-risk condition associated with important adverse maternal and neonatal outcomes.

Preeclampsia: Risk Factors, Diagnosis, Management, and the Cardiovascular Impact on the Offspring

Hypertensive disorders of pregnancy affect up to 10% of pregnancies worldwide, which includes the 3%–5% of all pregnancies complicated by preeclampsia. Preeclampsia is defined as new onset hypertension after 20 weeks’ gestation with evidence of maternal organ or uteroplacental dysfunction or proteinuria. Despite its prevalence, the risk factors that have been identified lack accuracy in predicting its onset and preventative therapies only moderately reduce a woman’s risk of preeclampsia. Preeclampsia is a major cause of maternal morbidity and is associated with adverse foetal outcomes including intra-uterine growth restriction, preterm birth, placental abruption, foetal distress, and foetal death in utero. At present, national guidelines for foetal surveillance in preeclamptic pregnancies are inconsistent, due to a lack of evidence detailing the most appropriate assessment modalities as well as the timing and frequency at which assessments should be conducted. Current management of the foetus in preeclampsia involves timely delivery and prevention of adverse effects of prematurity with antenatal corticosteroids and/or magnesium sulphate depending on gestation. Alongside the risks to the foetus during pregnancy, there is also growing evidence that preeclampsia has long-term adverse effects on the offspring. In particular, preeclampsia has been associated with cardiovascular sequelae in the offspring including hypertension and altered vascular function.

Relationship between Helicobacter pylori infection and osteoporosis: a systematic review and meta-analysis

OBJECTIVES

Many studies have explored the association between Helicobacter pylori infection and osteoporosis. However, the results remain controversial. Therefore, we performed this systematic review and meta-analysis to evaluate the association between H. pylori infection and osteoporosis.

DESIGN

Systematic review and meta-analysis of case-control studies.

DATA SOURCES

Databases, including PubMed, Embase, Web of Science and Chinese Biomedical Literature Database, were screened from inception to 30 April 2018.

ELIGIBILITY CRITERIA

Case-control studies aimed at assessing the association between H. pylori infection and osteoporosis.

DATA EXTRACTION AND ANALYSIS

Study characteristics and study quality sections were reviewed. Studies were selected, and data were extracted by two reviewers. Pooled ORs and 95% CIs were calculated using random effects model if heterogeneity existed; otherwise, fixed effects model was used. Subgroup analyses were performed to explore the source of heterogeneity. Publication bias and sensitivity analyses were also tested.

RESULTS

A total of 21 studies with 9655 participants were included in our analyses. Taking together, we found that H. pylori infection was associated with increased odds of osteoporosis (OR (95% CI): 1.39 (1.13 to 1.71)); there was no significant difference between osteoporosis and osteopaenia; the association between osteoporosis and H. pylori infection was relatively higher in men than women but did not reach significant level. However, the decrease of bone mineral density in H. pylori-positive patients was not significant when compared with H. pylori negative controls, which may due to the sample size.

CONCLUSIONS

Our meta-analysis suggests an association between osteoporosis and H. pylori infection. The clinicians should pay more attention to the patients infected with H. pylori. Further studies were still needed to exploring the confounding factors among studies and to elucidate the underlying biological mechanisms.

Helicobacter pylori and extragastric diseases

Many studies have been performed in the last year concerning the potential role of Helicobacter pylori in different extragastric diseases, reinforcing the idea that specific microorganisms may cause diseases even far from the primary site of infection. While the role of H. pylori on idiopathic thrombocytopenic purpura, sideropenic anemia, and vitamin B12 deficiency has been well established, there is a growing interest in other conditions, such as cardiovascular, neurologic, dermatologic, obstetric, immunologic, and metabolic diseases. Concerning neurologic diseases, there is a great interest in cognitive impairment and neurodegeneration. The aim of this review was to summarize the results of the most relevant studies published over the last year on this fascinating topic.

Current understanding and management of Helicobacter pylori infection: an updated appraisal

In addition to its role in gastric conditions, Helicobacter pylori has been found to contribute to the development of several non-gastric issues in recent years. Eradication therapy is the only effective management strategy to minimize the H. pylori-related gastric cancer and extra-gastric complications. For an effective “test and treat” strategy, diagnosis and therapy are both important. Because the infection is usually asymptomatic, patient selection is a critical issue for timely diagnosis and many clinical and demographic factors should be considered. Clarithromycin and metronidazole resistance rates also need to be considered while eradication therapy is offered. In this report, we discuss the issues which must be taken into account for the correct and timely diagnosis and for the antibiotic therapy-based management of H. pylori infection.