Trajectories of asthma symptom presenting as wheezing and their associations with family environmental factors among children in Australia: evidence from a national birth cohort study

Prevalence and risk factors for childhood asthma: a systematic review and meta-analysis

BACKGROUND

This study aimed to systematically review and perform a meta-analysis on epidemiological studies in order to estimate the global and regional prevalence and to identify risk factors associated with childhood asthma.

METHODS

A comprehensive search of the PubMed, Embase, and Cochrane Library electronic databases was conducted for relevant literature published from their inception to March 31, 2023. The primary endpoint was the prevalence of childhood asthma. Secondary endpoint focused on the identification of risk factors associated with childhood asthma.

RESULTS

A total of 1,547,404 children participated in the 164 studies selected for the meta-analysis. The overall prevalence of childhood asthma was 10.2% (95% CI: 9.5-11.0%), while the prevalence of childhood asthma in Asia, Europe, Latin America, North America, Oceania, Africa, or Eurasia were 10% (95%CI: 7-13%), 9% (95%CI: 7-12%), 14% (95%CI: 9-20%), 13% (95%CI: 12-14%), 23% (95%CI: 19-28%), 11% (95%CI: 7-19%), and 8% (95%CI: 2-27%), respectively. Moreover, the identified risk factors for childhood asthma included older age, male sex, obesity, parental smoking, high education of the mother, premature birth, cesarean section, no breastfeeding, family history of asthma, rhinitis, eczema, pets, high density of road traffic, meat, margarine, fast food, paracetamol use, and antibiotic use.

CONCLUSION

Childhood asthma is common, and the prevalence of asthma is highest in Oceania, with a lower prevalence in Eurasia. Moreover, the risk factors for childhood asthma were comprehensively identified, and health education should be provided to prevent modifiable factors.

Machine learning-derived asthma and allergy trajectories in children: a systematic review and meta-analysis

INTRODUCTION

Numerous studies have characterised trajectories of asthma and allergy in children using machine learning, but with different techniques and mixed findings. The present work aimed to summarise the evidence and critically appraise the methodology.

METHODS

10 databases were searched. Screening, data extraction and quality assessment were performed in pairs. Trajectory characteristics were tabulated and visualised. Associated risk factor and outcome estimates were pooled using a random-effects meta-analysis.

RESULTS

89 studies were included. Early-onset (infancy) persistent, mid-onset (∼2-5 years) persistent, early-onset early-resolving (within ∼2 years) and early-onset mid-resolving (by ∼3-6 years) wheezing and eczema, respectively, were the most commonly identified disease trajectories. Intermediate/transient trajectories were rare. Male sex was associated with a higher risk of most wheezing trajectories and possibly with early-resolving eczema, while being slightly protective against mid-onset persistent eczema. Parental disease/genetic markers were associated with persistent trajectories of wheezing and eczema, respectively. Prenatal (and less so postnatal) tobacco smoke exposure was associated with most wheezing trajectories, as were lower respiratory tract infections in infancy (particularly with the early-onset resolving patterns). Most studies (69%) were of low methodological quality (particularly in modelling approaches and reporting). Few studies investigated allergic multimorbidity, allergic rhinitis and food allergy.

CONCLUSIONS

Childhood asthma/wheezing and eczema can be characterised by a few relatively consistent trajectories, with some actionable risk factors such as pre-/postnatal smoke exposure. Improved computational methodology is warranted to better assess generalisability and elucidate the validity of intermediate/transient trajectories. Likewise, allergic multimorbidity and trajectories of allergic rhinitis and food allergy need to be further elucidated.

Origins and developmental paths of medical conditions from mid-childhood to mid-adolescence in Australia: Early-life adverse conditions and their lasting effects

This study investigates various common medical conditions affecting Australian children aged 4-14 years and the impact of prenatal and early-life conditions on these health conditions using a large national data set (n = 4122) with 15 years of follow-up. Consistent with the developmental origins of health and diseases hypothesis and the life-course models of health, the in-utero environment and parental financial hardship during pregnancy and shortly after birth play a significant role and have a lasting impact on the medical conditions of children. These significant effects are not reduced by controlling for child, family, and neighbourhood characteristics. The impact of improvements in family income when the child is aged 4-14 years does not compensate for the impact of health disadvantages in the prenatal and postnatal period.

Airway epithelium respiratory illnesses and allergy (AERIAL) birth cohort: study protocol

Introduction

Recurrent wheezing disorders including asthma are complex and heterogeneous diseases that affect up to 30% of all children, contributing to a major burden on children, their families, and global healthcare systems. It is now recognized that a dysfunctional airway epithelium plays a central role in the pathogenesis of recurrent wheeze, although the underlying mechanisms are still not fully understood. This prospective birth cohort aims to bridge this knowledge gap by investigating the influence of intrinsic epithelial dysfunction on the risk for developing respiratory disorders and the modulation of this risk by maternal morbidities, in utero exposures, and respiratory exposures in the first year of life.

Methods

The Airway Epithelium Respiratory Illnesses and Allergy (AERIAL) study is nested within the ORIGINS Project and will monitor 400 infants from birth to 5 years. The primary outcome of the AERIAL study will be the identification of epithelial endotypes and exposure variables that influence the development of recurrent wheezing, asthma, and allergic sensitisation. Nasal respiratory epithelium at birth to 6 weeks, 1, 3, and 5 years will be analysed by bulk RNA-seq and DNA methylation sequencing. Maternal morbidities and in utero exposures will be identified on maternal history and their effects measured through transcriptomic and epigenetic analyses of the amnion and newborn epithelium. Exposures within the first year of life will be identified based on infant medical history as well as on background and symptomatic nasal sampling for viral PCR and microbiome analysis. Daily temperatures and symptoms recorded in a study-specific Smartphone App will be used to identify symptomatic respiratory illnesses.

Discussion

The AERIAL study will provide a comprehensive longitudinal assessment of factors influencing the association between epithelial dysfunction and respiratory morbidity in early life, and hopefully identify novel targets for diagnosis and early intervention.

Prevalence of Wheezing and Its Association with Environmental Tobacco Smoke Exposure among Rural and Urban Preschool Children in Mpumalanga Province, South Africa

BACKGROUND

This study aimed to investigate the prevalence of wheezing and its association with environmental tobacco smoke exposure among rural and urban preschool children in Mpumalanga province, South Africa, an area associated with poor air quality.

METHODS

In this study, parents/caregivers of preschool children (n = 3145) completed a modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Data were analysed using multiple logistic regression models.

RESULTS

The overall prevalence of Wheeze Ever was 15.14%, with a higher prevalence in urban preschoolers than rural preschoolers (20.71% vs. 13.30%, p < 0.000). Moreover, the total prevalence of Asthma Ever was 2.34%. The prevalence was greater in urban preschoolers than in rural preschoolers (3.92% vs. 1.81%, p < 0.001). In the final adjusted model, both urban- and rural-area children who lived with one or more people who smoked in the same household (WE: OR 1.44, 95% CI 1.11-1.86) (CW: OR 2.09, 95% CI 1.38-3.16) and (AE: OR 2.49, 95% CI 1.12-5.54) were found to have an increased likelihood of having Wheeze Ever, Current Wheeze, and Asthma Ever as compared to those who lived with non-smokers.

CONCLUSIONS

The implementation of smoking limits and prohibition is crucial in areas that are frequented or utilized by children. Hence, it is imperative for healthcare providers to actively champion the rights of those who do not smoke within the society, while also endorsing legislative measures aimed at curtailing the extent of tobacco smoke exposure.

Trajectories of psychosocial environmental factors and their associations with asthma symptom trajectories among children in Australia

INTRODUCTION

Several psychosocial factors, such as maternal mental health and parents' financial hardship, are associated with asthma symptoms among children. So, we aim to investigate the changing patterns of important psychosocial environmental factors and their associations with asthma symptom trajectories among children in Australia.

METHODS

We considered asthma symptoms as wheezing (outcome) and psychosocial environmental factors (exposures) from 0/1 year to 14/15 years of the participants from the "Longitudinal Study of Australian Children (LSAC)" for this study. We used group-based trajectory modeling to identify the trajectory groups for both exposure and outcome variables. Associations between psychosocial factors and three distinct asthma symptom trajectories were assessed by multivariable logistic regression.

RESULTS

We included 3917 children from the LSAC birth cohort in our study. We identified distinct trajectories for maternal depression, parents' financial hardship, parents' stressful life events and parents' availability to their children from birth to 14/15 years of age. Compared to the "low/no" asthma symptom trajectory group, children exposed to a "moderate & increasing" maternal depression, "moderate & declining" parents' financial hardship, and "moderate & increasing" parents' stressful life events were significantly associated (relative risk ratio [RRR]: 1.55, 95% confidence interval [CI]: 1.27, 1.91; RRR: 1.40, 95%; CI: 1.15, 1.70; RRR: 1.77, 95%; CI: 1.45, 2.16) with "persistent high" asthma symptom trajectory.

CONCLUSION

Several psychosocial factors that are potential stressors for mental health increase the risk of having an adverse asthma symptom trajectory during childhood. Further attention should be given to reducing exposure to maternal depression, parents' financial hardship, and parents' stressful live events for long-term asthma control in children.

Airway Epithelium Respiratory Illnesses and Allergy (AERIAL) birth cohort: study protocol

Introduction

Recurrent wheezing disorders including asthma are complex and heterogeneous diseases that affect up to 30% of all children, contributing to a major burden on children, their families, and global healthcare systems. It is now recognized that a dysfunctional airway epithelium plays a central role in the pathogenesis of recurrent wheeze, although the underlying mechanisms are still not fully understood. This prospective birth cohort aims to bridge this knowledge gap by investigating the influence of intrinsic epithelial dysfunction on the risk for developing respiratory disorders and the modulation of this risk by maternal morbidities, in utero exposures, and respiratory exposures in the first year of life.

Methods and Analysis

The Airway Epithelium Respiratory Illnesses and Allergy (AERIAL) study is nested within the ORIGINS Project and will monitor 400 infants from birth to five years. The primary outcome of the AERIAL study will be the identification of epithelial endotypes and exposure variables that influence the development of recurrent wheezing, asthma, and allergic sensitisation. Nasal respiratory epithelium at birth to six weeks, one, three, and five years will be analysed by bulk RNA-seq and DNA methylation sequencing. Maternal morbidities and in utero exposures will be identified on maternal history and their effects measured through transcriptomic and epigenetic analyses of the amnion and newborn epithelium. Exposures within the first year of life will be identified based on infant medical history as well as on background and symptomatic nasal sampling for viral PCR and microbiome analysis. Daily temperatures and symptoms recorded in a study-specific Smartphone App will be used to identify symptomatic respiratory illnesses.

Ethics and Dissemination

Ethical approval has been obtained from Ramsey Health Care HREC WA-SA (#1908). Results will be disseminated through open-access peer-reviewed manuscripts, conference presentations, and through different media channels to consumers, ORIGINS families, and the wider community.

Trajectories of neighborhood environmental factors and their associations with asthma symptom trajectories among children in Australia: evidence from a national birth cohort study

PURPOSE

This study aims to investigate the prospective associations of neighborhood environmental exposure trajectories with asthma symptom trajectories during childhood developmental stages.

METHODS

We considered asthma symptom, neighborhood environmental factors, and socio-demographic data from the "Longitudinal Study of Australian Children (LSAC)". Group-based trajectory modeling was applied to identify the trajectories of asthma symptom, neighborhood traffic conditions, and neighborhood livability scales (considered for safety and facilities). We used multivariable logistic regression models to assess associations between various neighborhood environmental factors and asthma symptom trajectories.

RESULTS

We included 4,174 children from the LSAC cohort in our study. Three distinct trajectories for asthma symptom were the outcome variables of this study. Among the neighborhood environmental factors, we identified two distinct trajectories for the prevalence of heavy traffic on street, and two trajectories of neighborhood liveability scale. Compared to the 'Low/no' asthma symptoms trajectory group, children exposed to a 'persistently high' prevalence of heavy traffic on street was also significantly associated with both 'transient high' [relative risk ratio (RRR):1.40, 95% CI:1.25,1.58) and 'persistent high' (RRR: 1.33, 95% CI:1.17,1.50)] asthma symptom trajectory groups. Trajectory of moderate and static neighborhood liveability score was at increased risk of being classified as 'transient high' (RRR:1.16, 95% CI:1.07,1.25) and 'persistent high' (RRR:1.38, 95% CI:1.27,1.50) trajectories of asthma symptom.

CONCLUSION

Exposure to heavy traffic and poor neighborhood liveability increased the risk of having an unfavourable asthma symptom trajectory in childhood. Reducing neighborhood traffic load and improving neighborhood safety and amenities may facilitate a favorable asthma symptom trajectory among these children.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40201-022-00824-z.