The risk of Helicobacter pylori infection for adverse pregnancy outcomes: A systematic review and meta-analysis

Overview of foodborne hazards associated with inflammation and metabolic health

Access to safe and nutritious food is key to ensuring health and well-being and is critical to meeting the United Nations' Sustainable Development Goals. However, a synthesis of the associations between foodborne illness and malnutrition, such as metabolic health, remains a gap in the literature base. In this review, we summarized existing evidence on the impacts of biological and chemical hazards on nutrition-related health outcomes, specifically overweight and obesity, inflammation, metabolic disease, thyroid function, cancer development, and adverse birth outcomes, examining physiological mechanisms, epidemiological associations, and animal studies. Mechanisms between some foodborne hazards, such as H. pylori, and adverse pregnancy outcomes, e.g., gestational diabetes mellitus, or between nitrates and impaired thyroid function, are relatively well-studied. However, evidence on the effects of many other chemical hazards on metabolic and human health remains limited: for example, while arsenic exposure is associated with adverse birth outcomes, the limited availability of dose-response studies and other challenges limit ascertaining its causal role. Untangling these associations and physiological mechanisms is of high relevance for both high- as well as low- and middle-income countries. Emerging technologies and novel assessment techniques are needed to improve the detection and understanding of understudied and complex foodborne diseases, particularly those arising from chemical hazards. These evidence gaps are highlighted in this review, as well as the need for establishing surveillance systems for monitoring foodborne diseases and metabolic health outcomes across populations.

Assessment of adverse pregnancy outcomes associated with Helicobacter pylori infection

The background of Helicobacter pylori (H. pylori) infection is complex, and its influence on adverse pregnancy outcomes is inconsistently reported. We performed a multi-institutional, retrospective analysis using de-identified electronic health records from the TriNetX Research Network to compare various pregnancy outcomes in women with and those without H. pylori infection. A 1:1 propensity score matching (PSM) was performed with covariates including age, race, pre-pregnancy body mass index, history of diabetes, presence of gastroesophageal reflux disease nausea, and vomiting. Between January 2010 and October 2024, we identified 5,148 pregnant women with H. pylori infection and 4,740,133 women from the general population with no positive test results or diagnosis for H. pylori. Following PSM, both cohorts contained 5,116 patients each. Our results showed that H. pylori infection was associated with an increased risk of hyperemesis gravidarum. A significant association with hyperemesis gravidarum were also found when comparing patients with positive H. pylori test results to those with negative test results. Secondary outcomes also showed positive correlations between H. pylori infection and low gestational weight gain, fetal growth restriction, and intrauterine fetal demise. Contrarily, the risk of gestational diabetes, preeclampsia and preterm delivery did not increase significantly. Our study confirmed the association between H. pylori infection and multiple adverse pregnancy outcomes. Given its high prevalence, further research is warranted to investigate effective screening and treatment protocols for H. pylori infection during pregnancy.

The association between the Helicobacter pylori infection and the occurrence of gestational diabetes: a systematic review and meta-analysis

BACKGROUND

This meta-analysis aims to establish a more precise association between gestational diabetes mellitus (GDM) incidence and H. pylori infection by amalgamating findings from prior case-control and cohort studies.

METHODS

To identify relevant studies, we conducted a comprehensive search using the Excerpta Medica Database (Embase), PubMed (Medline), Web of Science (ISI), and Scopus from January 1990 to November 2022. The screening process involved reviewing the entire text, abstracts, and titles of retrieved articles. Subsequently, data extraction was performed from the selected articles, and their quality was assessed using the Newcastle-Ottawa Scale checklist. Version 17 of STATA software was utilized for the analysis, with relative risks (RR) calculated along with their 95% confidence intervals (CI) to quantify the impact of the included studies.

RESULTS

This meta-analysis included eight observational and analytical studies. The combined risk of gestational diabetes mellitus (GDM) in pregnant women with H. pylori infection was found to be 1.97 times higher compared to pregnant women without infection (RR: 1.97; 95% CI 1.57-2.47; I2 = 0.00%; P = 0.84).

CONCLUSION

Pregnant women with H. pylori infection are at an increased risk of developing gestational diabetes.

Knowledge, attitudes and practices regarding zoonotic diseases among cat and dog owners in Bangladesh

The close relationship between human and companion animals like cats and dogs raises public health concerns regarding the potential transmission of zoonotic diseases in Bangladesh. The study aimed to evaluate the cat and dog owners' knowledge, attitudes, practices, and risk perception concerning zoonotic diseases for designing effective interventions and reducing disease transmission. A cross-sectional survey was conducted among 480 pet owners in various region of Bangladesh. For data collection, a structured, closed-ended questions were implemented. The data collection was anonymous and individuals were chosen through a random selection method. Responses were classified to evaluate comprehensive knowledge, using a threshold value of ≥65%. Quantitative score was created to measure Knowledge, Attitudes, and Practices, and these scores were divided into categories of good and poor knowledge, positive and negative attitudes, as well as correct and incorrect practices. The analysis included the application of both descriptive statistics and logistic regression analysis. The findings showed that females made up more than half of the survey participants (55.2%), with the predominant pet owned being cats (73.1%). Overall, only a small portion (21.25%) of the survey respondents demonstrated good knowledge about the topic as measured by a dichotomous outcome. A larger proportion of participants (84.58%) exhibited a positive attitude towards zoonotic diseases. However, when it came to correct practices, about one-third (29.79%) of performed satisfactorily. It is noteworthy that 90.4% of the participants exhibited a high level of understanding regarding the transmission of rabies through dog bites. The knowledge and practices of owners were markedly impacted by their education, occupation, and geographic location. Furthermore, 48.1% identified 'social media' as their primary source of information, and 80.0% regarded vaccination as a preventive measure. The study reveals gaps in knowledge and practices of risks regarding zoonotic diseases among pet owners in Bangladesh. It is crucial to implement focused educational initiatives and preventative measures to effectively tackle gaps in knowledge concerning zoonotic diseases and to avert potential infections.

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 association between Helicobacter pylori and gastrointestinal disorders during pregnancy: A Multicenter retrospective study

BACKGROUND

Some gastrointestinal disorders may be associated with Helicobacter pylori infection, which not only affect maternal health, but may also lead to adverse pregnancy outcomes. We aim to explore the association between H. pylori and gastrointestinal disorders in pregnant women.

MATERIALS AND METHODS

In total, 503 patients were retrospectively analyzed and divided into the H. pylori-uninfected group, the H. pylori-infected group, or the H. pylori-eradicated group. We analyzed the influence of H. pylori on gastrointestinal diseases during pregnancy among the groups, as well as the severity, symptoms, laboratory tests of the H. pylori-related diseases.

RESULTS

Pregnant women with H. pylori infection had higher risk of nausea and vomiting of pregnancy (NVP) (p < 0.001), severe NVP(p = 0.012), hyperemesis gravidarum (p = 0.027), hematemesis (p = 0.018), hyponatremia (p = 0.033), as well as functional dyspepsia symptoms including epigastric pain (p = 0.004), bloating (p = 0.024), and feeling full quickly in a meal (p = 0.031) compared with those without H. pylori infection. While the prevalence of NVP (p = 0.024), severe NVP (p = 0.009), epigastric pain (p = 0.037), and bloating (p = 0.032) were lower in H. pylori-eradicated pregnant women than in H. pylori-infected women. In addition, pregnant women with H. pylori infection had higher risk of spontaneous preterm birth than whom without H. pylori infection (p = 0.033).

CONCLUSIONS

Helicobacter pylori infection was associated with higher risks of NVP, severe NVP, hyperemesis gravidarum, functional dyspepsia, and spontaneous preterm birth in pregnant women.

Helicobacter pylori infection in pregnant women: Gastrointestinal symptoms and pregnancy- related disorders

Helicobacter pylori (H. Pylori) is a gram-negative, flagellated and spiral-shaped bacterial pathogen that impacts approximately 46% among pregnant women globally and has been associated with various maternal-fetal complications. Iron deficiency anemia, fetal growth restriction, cardiovascular diseases, and insufficient nutrient absorption can be observed in pregnant women, as well as miscarriages and pregnancy-specific hypertensive disease, such as pre-eclampsia. Thus, the evidence supports the influence of H. pylori infection on fetal implantation/placentation failure, and positive strains of the cytotoxin-associated gene A of H. Pylori were reported as the most prevalent in these conditions. However, current knowledge indicates a relationship between this infection and the occurrence of hyperemesis gravidarum, characterized by frequent nausea and vomiting. Regarding the diagnosis of this bacterial infection, non-invasive approaches such as stool antigen test, urea breath test, and serological tests are more accepted during pregnancy, as they are easy to carry out and cost-effective. Finally, the bacteria eradication therapy should consider the risks and benefits for the pregnant woman and her child, with pharmacological intervention depending on the clinical presentation.

Lifestyle-based nomogram for identifying the Chaoshan inhabitants of China at high risk of Helicobacter pylori infection

BACKGROUND

Helicobacter pylori (HP) infection is associated with various diseases. Early detection can prevent the onset of illness. We constructed a nomogram to predict groups at high risk of HP infection.

METHODS

Patients who underwent regular medical check-ups at hospital in Chaoshan, China from March to September 2022 were randomly allocated to the training and validation cohorts. Risk factors including basic characteristics and lifestyle habits associated with HP infection were analyzed by logistic regression analyses. The independent varieties were calculated and plotted into a nomogram. The nomogram was internally validated by receiver operating characteristic curve, calibration, and decision curve analyses (DCAs).

RESULTS

Of the 945 patients, 680 were included in the training cohort and 265 in the validation cohort. 356 patients in training cohort with positive 13 C-UBT results served as the infected group, and 324 without infection were the control group. The multivariate regression analyses showed that the risk factors for HP infection included alcohol consumption (OR = 1.29, 95%CI = 0.78-2.13, P = 0.03), family history of gastric disease (OR = 4.35, 95%CI = 1.47-12.84, P = 0.01), living with an HP-positive individual (OR = 18.09, 95%CI = 10.29-31.82, P < 0.0001), drinking hot tea (OR = 1.58, 95%CI = 1.05-2.48, P = 0.04), and infection status of co-drinkers unknown (OR = 2.29, 95%CI = 1.04-5.06, P = 0.04). However, drinking tea > 3 times per day (OR = 0.56, 95%CI = 0.33-0.95, P = 0.03), using serving chopsticks (OR = 0.30, 95%CI = 0.12-0.49, P < 0.0001) were protective factors for HP infection. The nomogram had an area under the curve (AUC) of 0.85 in the training cohort. The DCA was above the reference line within a large threshold range, indicating that the model was better. The calibration analyses showed the actual occurrence rate was basically consistent with the predicted occurrence rate. The model was validated in the validation cohort, and had a good AUC (0.80), DCA and calibration curve results.

CONCLUSIONS

This nomogram, which incorporates basic characteristics and lifestyle habits, is an efficient model for predicting those at high risk of HP infection in the Chaoshan region.

Association Between Helicobacter pylori, Adverse Gynecological and Pregnancy Outcomes, and Some Cancers: An Overview of Metanalyses

Context: The number of meta-analyses published about Helicobacter pylori-associated diseases that clinicians must comprehensively know about are scarce. This overview aims to give comprehensive knowledge on the fascinating topic of Helicobacter pylori-associated diseases. Methods: The search strategy was to systematically screen the articles evaluating the association between H. pylori infection and gynecological and reproductive health issues and cancers published on the authentic databases of Scopus, MEDLINE, and Web of Sciences from the inception until 2022. Results: Fifteen meta-analyses were included in the overview. The H. pylori infections were significantly associated with general adverse pregnancy outcomes such as gestational diabetes mellitus, preeclampsia, and hyperemesis gravidarum and adverse birth outcomes such as birth defect and fetal growth restriction. H. pylori infection was not associated with a deficiency of micronutrients (B2, folate, and ferritin) but was associated with an increased risk of iron-deficiency anemia during pregnancy. In esophagus cancer, H. pylori infection was significantly reduced in adenocarcinoma but not in esophageal squamous cell carcinoma. There was no significant association between H. pylori infection and the risk of asthma. The results also indicated a significant association between H. pylori infection and an elevated risk of colorectal cancer, colorectal adenoma, and the risk of asthma and lung cancer. Results of metanalysis are not consistently reproducible regarding spontaneous abortion and pancreatic cancer. Conclusions: Our overview revealed a significant relationship between H. pylori infection and several cancers, namely colorectal, lung, and colorectal adenoma, as well as gynecological and reproductive health issues.

Review article: Functional dyspepsia and pregnancy-Effects and management in a special population

BACKGROUND

Around 10% of Americans meet the Rome IV criteria for functional dyspepsia (FD), with a significantly higher rate in women. FD also has a higher prevalence in women below the age of 50, suggesting that women who are affected are likely to be of reproductive age. Unfortunately, there is a lack of research or evidence-based guidelines on managing FD in pregnancy.

AIMS AND METHODS

To address this issue, we aimed to perform a systematic review of the interactions between FD and pregnancy and managing pre-existing FD in the peripartum and post-partum phases using current lifestyle, pharmacological, non-pharmacological and alternative medicine interventions.

RESULTS

Due to the lack of Rome IV FD-specific data in pregnancy, we instead performed a narrative review on how existing FD interventions could be extrapolated to the pregnant population. Where possible we use the highest level of available evidence or official guidelines to answer these questions, which often involves synthesising treatment and safety evidence of these interventions in other diseases during pregnancy. Finally, we highlight current substantial knowledge gaps requiring further research for the safe management of a pregnant patient with pre-existing FD.

CONCLUSIONS

Overall, despite the paucity of knowledge of treating FD during pregnancy, providers can mitigate this uncertainty by planning ahead with the patient. Patients should ideally minimise treatment until after breastfeeding. However, interdisciplinary resources are available to ensure that minimal-risk interventions are maximised, while interventions with more risks, if necessary, are justifiable by both the patient and the care team. Future investigations should continue to elicit the mechanistic relationship between FD and pregnancy while cautiously expanding prospective research on promising and safe therapies in pregnant patients with pre-existing FD.

Early exposure to infections increases the risk of allergic rhinitis-a systematic review and meta-analysis

OBJECTIVE

The purpose of this study was to provide evidence for early life care by meta-analyzing the relationship between infection during pregnancy and up to 2 years of age and the risk of subsequent allergic rhinitis (AR).

METHODS

Published studies up to April 2022 were systematically searched in PubMed, Embase, Web of Science, Cochrane Library, SinoMed, CNKI, Wanfang Database, and VIP. Literature screening, including quality assessment, was performed, and the effect values (OR, HR, RR) and 95% confidence intervals (95% CI) of infection during pregnancy and up to 2 years of age and allergic rhinitis were extracted from each qualified study.

RESULTS

In total, 5 studies with a sample size of 82,256 reported the relationship between infection during pregnancy and offspring AR. Meta-analysis showed that maternal infection during pregnancy was associated with an increased risk of childhood AR in offspring (OR = 1.34, 95% CI: 1.08-1.67). Altogether, 13 studies with a sample size of 78,426 reported evidence of an association between infection within 2 years of age and subsequent AR in children. A pooled meta-analysis of all studies showed that early infection within 2 years of age was closely associated with childhood AR (OR = 1.25, 95% CI: 1.12-1.40), especially upper respiratory tract infection (OR = 1.32, 95% CI: 1.06-1.65) and gastrointestinal infections (OR = 1.37, 95% CI: 1.01-1.86), but ear infection showed similar results in the cohort study (OR = 1.13, 95% CI: 1.04-1.22).

CONCLUSION

Current evidence suggests that infection during pregnancy, early upper respiratory infection, gastrointestinal infections and ear infection within 2 years of age would increase the risk of AR in children. Therefore, the prevention of infection during pregnancy and in infancy and young children needs to be emphasized.

Association between Pet Ownership and Threatened Abortion in Pregnant Women: The China Birth Cohort Study

Background: The aim of this study was to assess the association between pet ownership and threatened abortion (TA) in pregnant Chinese women. Materials and Methods: We enrolled pregnant women from 18 provinces and autonomous regions across China between November 2017 and December 2020. Participants were grouped based on the presence or absence of pet ownership. Pet owners were further sub-grouped based on the presence or absence of close contact with their pets. Pet species included cats, dogs, and both. Generalised linear mixed models, with province as a random effect, were used to estimate the associations between pet ownership and TA. Results: Pet ownership, whether or not one had close contact with pets, was associated with greater odds of TA (OR: 1.30, 95% CI: 1.21, 1.40). Keeping pet cats (OR: 1.24, 95% CI: 1.11, 1.40), dogs (OR: 1.29, 95% CI: 1.18, 1.41), or both cats and dogs (OR: 1.36, 95% CI: 1.04, 1.68) during pregnancy were all risk factors for TA. We observed significant group differences (p for difference < 0.05) in pre-pregnancy body mass index, education levels, and annual household income. Conclusions: Cat or dog ownership during pregnancy was associated with an increased risk of TA, especially among overweight, less educated, or lower-income participants.

Helicobacter pylori-Related Extraintestinal Manifestations—Myth or Reality

It is well documented that Helicobacter pylori (H. pylori) can cause both gastrointestinal and extraintestinal manifestations. The latter one represents a major burden in terms of diagnosis and treatment. H. pylori-associated systemic subclinical inflammation is mostly responsible for the development of extraintestinal manifestations, and its early eradication might result in preventing all adverse events related to their occurrence. Thus, it was suggested that H. pylori might be associated with iron deficiency anemia, thrombocytopenia (immune thrombocytopenic purpura), Schonlein Henoch purpura, failure to thrive, vitamin B12 deficiency, diabetes mellitus, body mass index, cardiovascular diseases, as well as certain neurological conditions. Nevertheless, studies showed both pros and cons in terms of the role of H. pylori in the development of previously mentioned clinical entity underlining the crucial need for further studies on these topics. Although most of these extraintestinal manifestations occur during adulthood, we must not forget that H. pylori infection is acquired mainly during childhood, and thus its early diagnosis and eradication might represent the cornerstone in the prevention of H. pylori-induced inflammatory status and consequently of all related extraintestinal conditions.

Adverse pregnancy outcomes and Helicobacter pylori infection: A meta-analysis

INTRODUCTION

Helicobacter pylori infection during pregnancy has some adverse effects, but its effects are still conflicting. This meta-analysis study was performed to assess the relationship between H pylori infection and adverse effects during pregnancy.

METHODS

Through a systematic literature search up to August 2020, 31 studies included 16 887 pregnant females at baseline and reported a total of 5852 H pylori infection positive and 8196 H pylori infection negative pregnant females, were found recording relationships between H pylori infection and adverse effects during pregnancy. Odds ratio (OR) with 95% confidence intervals (CIs) was calculated between H pylori infection positive vs H pylori infection negative in adverse effects during pregnancy using the dichotomous methods with a random or fixed-effect model.

RESULTS

H pylori infection positive during pregnancy was significantly related to higher rate of preeclampsia (OR, 2.68; 95% CI, 2.02-3.56, P < .001), foetal growth restriction (OR, 1.45; 95% CI, 1.26-1.66, P < .001), gestational diabetes mellitus (OR, 2.63; 95% CI, 1.51-4.59, P < .001), and hyperemesis gravidarum (OR, 14.45; 95% CI, 10.24-20.38, P < .001) compared with H pylori infection negative. However, H pylori infection positive during pregnancy was not significantly correlated with spontaneous onset of labour (OR, 1.00; 95% CI, 0.83-1.21, P = .98) compared with H pylori infection negative.

CONCLUSIONS

H pylori infection may have an independent relationship with certain adverse effects during pregnancy. H pylori infection positive during pregnancy was significantly related to a higher rate of preeclampsia, foetal growth restriction, gestational diabetes mellitus, and hyperemesis gravidarum compared with H pylori infection negative. This relationship encouraged us to recommend screening and treating females for H pylori infection before and during pregnancy to avoid any possible complications.

Helicobacter pylori infection and micronutrient deficiency in pregnant women: a systematic review and meta-analysis

Background

Over the last few years, epidemiological studies have shown that infection with Helicobacter pylori has a major effect on micronutrient deficiency as well as on adverse pregnancy outcomes. Importantly, there are gaps in understanding the linkage of H. pylori infection with micronutrients deficiency in pregnant women.

Objective

We conducted a systematic review and meta-analysis to estimate the association between H. pylori infection and micronutrient deficiencies in pregnant women.

Methods

A systematic literature search was conducted for relevant articles using PubMed, Web of Science, and Scopus database from inception to March 2020. The OR with 95% CIs was determined by meta-analysis of data extracted from the selected studies.

Results

From 2384 primary articles, 6 studies were selected for systematic reviews and 4 studies distinctively (with 1274 participants: 553 cases and 721 controls) were selected for meta-analysis. The meta-analysed fixed effect model estimated the odds of having H. pylori infection was not significantly higher among pregnant women with micronutrient deficiencies than those without deficiencies (OR=1.12, 95% CI 0.88 to 1.42, p=0.37). In the subgroup analysis, no correlation was found between H. pylori infection and vitamin B₁₂ (OR=0.74, 95% CI 0.45 to 1.21, p=0.22), folate (OR=1.07, 95% CI 0.73 to 1.58, p=0.73), and ferritin (OR=0.81, 95% CI 0.51 to 1.31, p=0.4). However, a positive correlation was found between iron-deficiency anaemia (IDA) and H. pylori infection (OR=16.23, 95% CI 4.19 to 62.93, p<0.0001) during pregnancy.

Conclusion

H. pylori infection is associated with increased risk of IDA but not with deficiency of other micronutrients in pregnancy.

PROSPERO registration number

CRD42019135683.

Helicobacter pylori infection increases the risk of metabolic syndrome in pregnancy: a cohort study

Background

The effects of Helicobacter pylori (H. pylori) infection on metabolic syndrome (MetS) in pregnant women are unclear to date. This study was designed to explore the relationship between H. pylori infection and MetS during pregnancy.

Methods

Pregnant women were enrolled in the prospective cohort study, and their demographic data and metabolic parameters were collected. H. pylori infection was measured using the C13 urea breath test. All enrolled patients were followed up until the last baby was born. Metabolic disorders, including elevated levels of serum triglycerides (TG), high-density lipoprotein (HDL) cholesterol and blood glucose (BG), and adverse pregnancy outcomes, including gestational diabetes mellitus (GDM), preeclampsia, spontaneous preterm birth (SPB), fetal growth restriction (FGR), and uncomplicated pregnancy, were recorded during follow up.

Results

There were 320 pregnant women enrolled in this study. They were divided into two groups according to H. pylori infection, and each group was then divided into two subgroups on whether their BMI was more than 24 or not. The results showed that H. pylori infection significantly increased the incidence of MetS as well as other metabolic disorders, especially in pregnant women with high BMI. Multivariable logistic regression analysis showed that risk factors of MetS were high BMI and H. pylori infection. Besides, H. pylori infection increased the incidence of GDM and preeclampsia and potentially reduced the incidence of uncomplicated pregnancy.

Conclusions

H. pylori infection in pregnant women acts as a crucial risk factor of Mets and affects the incidence of several adverse pregnancy outcomes.

Influence of residential greenness on adverse pregnancy outcomes: A systematic review and dose-response meta-analysis

BACKGROUND

With the development of urbanization, there is a decreasing tendency for people contact with natural greenness. Whether maternal exposure to greenness has an impact on pregnancy complications and pregnancy outcomes remains to be confirmed.

OBJECTIVES

To estimate the association and dose-response relationship between residential greenness and pregnancy outcomes.

DATA SOURCES

PubMed, Embase, Ovid, Scopus and Web of Science from inception to 1st December 2019 were searched.

SYNTHESIS METHODS

The summary regression coefficient (β) and odds ratio (OR) with corresponding 95% confidence interval (95%CI) were calculated. The linear dose-response relationship between greenness and adverse pregnancy outcomes was also investigated.

RESULTS

Overall, 36 studies with a total of 11,983,089 participants were included. Birth weight was significantly higher in highest level of greenness exposure group compared to lowest level group (e.g. β:20.22, 95%CI:13.50-26.93 at 100 m buffer). The odds of low birth weight (LBW) decreased in the highest level of group compared to lowest level group (e.g. OR:0.86, 95%CI:0.75-0.99 at 100 m buffer). The odds of small for gestational age (SGA) also decreased in the highest group (OR:0.93, 95%CI:0.88-1.00 at 100 m buffer). In addition, maternal exposure to greenness was associated with increased head circumference and decreased mental disorders. The dose-response models showed a 2% decrease risk of LBW per 0.1 normalized difference vegetation index (NDVI) increase within 300 m buffer (OR:0.98, 95%CI:0.97-0.99, P < 0.001) and a 1% decrease risk of SGA per 0.1 NDVI increase within 300 m buffer (OR:0.99, 95%CI:0.98-1.00, P = 0.037). No significant associations were found on preterm birth, gestational age, gestational diabetes mellitus, gestational hypertension or preeclampsia.

CONCLUSIONS

This review confirms an inverse association between residential greenness and adverse pregnancy outcomes. Findings of our study provide evidences for pregnant women to increase greenness exposure.

Association between H. pylori infection and health Outcomes: an umbrella review of systematic reviews and meta-analyses

OBJECTIVE

Systematic reviews and meta-analyses have revealed the associations between H. pylori infection and various health outcomes. We aimed to evaluate the strength and breadth of evidence on the associations.

DESIGN

Umbrella review of systematic reviews and meta-analyses.

SETTING

No settings.

PARTICIPANTS

No patients involved.

DATA SOURCES

Embase, PubMed, Web of Science, Cochrane Library Databases, CNKI, VIP database and Wangfang database from inception to February 1, 2019.

OUTCOMES MEASURES

Diverse diseases (such as cancer and ischaemic heart disease).

RESULTS

Sixty articles reporting 88 unique outcomes met the eligible criteria. 74 unique outcomes had nominal significance (p<0.05). Of the outcomes with significance, 61 had harmful associations and 13 had beneficial associations. Furthermore, 73% (64) of the outcomes exhibited significant heterogeneity . Of the these meta-analyses, 32 had moderate to high heterogeneity (I²=50%-75%) and 24 had high heterogeneity (I²>75%). Moreover, 20% exhibited publication bias (p<0.1). In addition, 97% of the methodological qualities were rated 'critically low'. 36% of the evidence qualities of outcomes were rated 'low', 56% of the evidence qualities were rated 'very low' and 8% of the evidence qualities were rated 'moderate'. H. pylori infection may be associated with an increased risk of five diseases and a decreased risk of irritable bowel syndrome.

CONCLUSION

Although 60 meta-analyses explored 88 unique outcomes, moderate quality evidence only existed for six outcomes with statistical significance. H. pylori infection may be associated with a decreased risk of irritable bowel syndrome and an increased risk of hypertriglyceridemia, chronic cholecystitis and cholelithiasis, gestational diabetes mellitus, gastric cancer and systemic sclerosis.

TRIAL REGISTRATION

CRD42019124680.

Current Resources for Evidence-Based Practice, November 2019

A review of new resources to support the provision of evidence-based care for women and infants.