Early-life infections in association with development of atopic dermatitis in infancy and early childhood: A nationwide nested case-control study

Time-dependent risk of atopic dermatitis following nontyphoidal Salmonella infection

BACKGROUND

The pathogenesis of atopic dermatitis (AD) remains unclear. Nontyphoidal Salmonella (NTS) infection might trigger immune-mediated reactions. We aimed to examine NTS and the risk of subsequent AD.

METHODS

From 2002 to 2015, eligible patients (aged 0-100 years) with NTS were identified. NTS and non-NTS groups were matched at a 1:10 ratio on age and sex. We utilized conditional multivariable Cox proportional hazard models to estimate the adjusted hazard ratio (aHR) and 95% confidence interval (CI) for AD development. Subgroup analyses were conducted based on age, sex, and severity of NTS infection. We utilized landmark analysis to explore the time-dependent hazard of AD following NTS.

RESULTS

In the NTS group (N = 6624), 403 developed AD. After full adjustment of demographics and comorbidities, the NTS group had a higher risk of AD than the reference group (aHR = 1.217, 95% CI = 1.096-1.352). Age-stratified analysis revealed that NTS group exhibited an elevated risk compared to the reference group, particularly among those aged 13-30 years (aHR = 1.25, 95% CI = 1.017-1.559), individuals aged 31-50 years (aHR = 1.388, 95% CI = 1.112-1.733), those aged 51-70 years (aHR = 1.301, 95% CI = 1.008-1.679), and individuals aged 71 years and over (aHR = 1.791, 95% CI = 1.260-2.545). Severe NTS was associated with a higher risk of AD than the reference group (aHR = 2.411, 95% CI = 1.577-3.685). Landmark analysis showed generally consistent findings.

CONCLUSIONS

Minimizing exposure to NTS infection may represent a prospective strategy for averting the onset and progression of atopic dermatitis.

Risk Factors of Onset Time and Persistence of Atopic Dermatitis in Children Under Age 5 Years: A Cross-Sectional Study

Background: The prevalence of atopic dermatitis (AD) is high among children, with development of AD occurring during early childhood in most affected children and some having a chronic disease course. Risk factors for AD in this group remain undefined. Objectives: We analyzed the medical records of children with AD under 5 years of age. We summarized characteristics of the natural course of AD in these children and explored relevant risk factors of AD in infancy and early childhood. Methods: Using a self-developed questionnaire, we investigated 716 children under 5 years of age who were treated for AD at the Dermatology Department of the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China. We conducted the study from October 2021 to September 2022 using telephone and on-site interviews with the children's parents. In parental interviews, data were gathered on neonatal diseases, comorbidities, parental allergy history, maternal history of tobacco and alcohol use, and basic infant information at birth. Some children were tested for serum total immunoglobulin E (IgE) before this study. Results: Neonatal hyperbilirubinemia, neonatal respiratory distress syndrome (NRDS), neonatal infection, and infection during childhood had a significant impact on persistent symptoms and the onset of first symptoms in children with AD (P < 0.05). Allergic diseases as common comorbidities with AD, which had earlier onset of AD related to more obvious disease activity (P < 0.05). Parental history of allergy was also significant in AD (P < 0.05). Serum total iIgE levels in children with AD showed an impact on the clinical course of AD; neonatal hyperbilirubinemia and NRDS may affect IgE levels (P < 0.05). Persistent AD had a significant effect on the physical growth of children with height/length for age Z score ≤3 and weight for height/length Z score ≤3 (P < 0.05). Conclusions: Early adverse events in infants, infection before onset, and susceptibility to infection may affect the onset and clinical course of childhood AD. Serum total IgE levels affect the progression of AD. Persistent AD in childhood may have a slight impact on children's physical growth.

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.

Early-Life Antibiotic Exposure Associated With Varicella Occurrence and Breakthrough Infections: Evidence From Nationwide Pre-Vaccination and Post-Vaccination Cohorts

Background

Antibiotic-driven dysbiosis may impair immune function and reduce vaccine-induced antibody titers.

Objectives

This study aims to investigate the impacts of early-life antibiotic exposure on subsequent varicella and breakthrough infections.

Methods

This is a nationwide matched cohort study. From Taiwan’s National Health Insurance Research Database, we initially enrolled 187,921 children born from 1997 to 2010. Since 2003, the Taiwan government has implemented a one-dose universal varicella vaccination program for children aged 1 year. We identified 82,716 children born during the period 1997 to 2003 (pre-vaccination era) and 48,254 children born from July 1, 2004, to 2009 (vaccination era). In the pre-vaccination era, 4,246 children exposed to antibiotics for at least 7 days within the first 2 years of life (Unvaccinated A-cohort) were compared with reference children not exposed to antibiotics (Unvaccinated R-cohort), with 1:1 matching for gender, propensity score, and non-antibiotic microbiota-altering medications. Using the same process, 9,531 children in the Vaccinated A-cohort and Vaccinated R-cohort were enrolled from the vaccination era and compared. The primary outcome was varicella. In each era, demographic characteristics were compared, and cumulative incidences of varicella were calculated. Cox proportional hazards model was used to examine associations.

Results

In the pre-vaccination era, the 5-year cumulative incidence of varicella in the Unvaccinated A-cohort (23.45%, 95% CI 22.20% to 24.70%) was significantly higher than in the Unvaccinated R-cohort (16.72%, 95% CI 15.62% to 17.82%) (p<.001). In the vaccination era, a significantly higher 5-year cumulative incidence of varicella was observed in the Vaccinated A-cohort (1.63%, 95% 1.32% to 1.93%) than in the Vaccinated R-cohort (1.19%, 95% CI 0.90% to 0.45%) (p=0.006). On multivariate analyses, early-life antibiotic exposure was an independent risk factor for varicella occurrence in the pre-vaccination (adjusted hazard ratio [aHR] 1.92, 95% CI 1.74 to 2.12) and vaccination eras (aHR 1.66, 95% CI 1.24 to 2.23). The use of penicillins, cephalosporins, macrolides, or sulfonamides in infancy was all positively associated with childhood varicella regardless of vaccine administration.

Conclusions

Antibiotic exposure in early life is associated with varicella occurrence and breakthrough infections.