Early Life Weight Gain and Development of Childhood Asthma in a Prospective Birth Cohort

Early-Life Weight Status and Risk of Childhood Asthma or Recurrent Wheeze in Preterm and Term Offspring

BACKGROUND

Excessive weight is associated with the development of childhood asthma. However, trends among preterm and term offspring may differ.

OBJECTIVE

To assess whether the association of longitudinal weight for age (WFA) and odds of asthma/recurrent wheeze in early life differs between children born preterm and those born at term.

METHODS

This study used prospectively collected data from the Vitamin D Antenatal Asthma Reduction Trial. Children (n = 804) were followed-up and anthropometric measurements, including WFA, were taken at birth and annually until the age of 6 years. The primary outcome was asthma/recurrent wheeze by age 3 and 6 years.

RESULTS

Among the offspring, 71 (8.8%) were premature. In all the children, the odds of asthma/recurrent wheeze increased by 15% (adjusted odds ratio [aOR], 1.15; 95% CI, 1.10-1.20; P < .001) by age 3 years and 9% (aOR, 1.09; 95% CI, 1.07-1.11; P < .001) by age 6 years for each unit increase in WFA z score. Odds were different between term and preterm offspring (Pinteraction < .001). In term offspring, the odds of having asthma/recurrent wheeze by age 3 and 6 years increased by 22% and 15%, respectively (aOR, 1.22, 95% CI, 1.16-1.27, P < .001, and aOR, 1.15, 95% CI, 1.11-1.18, P < .001). In preterm offspring, by age 3 years, odds of asthma/recurrent wheeze decreased by 10% for each unit increase in WFA z score (aOR, 0.90; 95% CI, 0.81-0.99; P = .030) and decreased by 27% by age 6 years (aOR, .73; 95% CI, 0.61-0.86; P < .001).

CONCLUSIONS

During early life, increasing standardized WFA is associated with higher odds of asthma/recurrent wheeze in term children. In contrast, in preterm children, a higher standardized WFA during catch-up growth may decrease the odds of asthma/recurrent wheeze associated with prematurity.

Growth pattern during early infancy, body mass index during childhood and childhood asthma

BACKGROUND

There is a lack of longitudinal studies of associations between growth from infancy to childhood and asthma development.

OBJECTIVE

The objective of the study was to investigate the effects of weight change during infancy, body mass index (BMI) and the interaction of these factors on the risk of childhood asthma.

METHODS

We enrolled children born in 2008 and 2009 at full-term and with normal birth weight. The weight change in infancy was grouped into slow, on-track and rapid. BMI status in childhood was stratified into low, normal and high groups and used as a time-varying variable. The outcome was asthma, defined as two or more diagnoses of asthma separated by at least 1 year after 2 years of age. The risk of asthma was assessed using Cox proportional hazard regression, with adjustment for sex, residence area at birth, economic status and feeding types in infancy.

RESULTS

Of 917,707 children born in Korea in 2008 and 2009, 271,871 were eligible for analysis. The risk of asthma was greater in groups with low birth weight (aHR 1.06, 95% CI 1.04 to 1.08), rapid body weight change during early infancy (aHR 1.08, 95% CI 1.07 to 1.10) and high BMI during childhood (aHR 1.06, 95% CI 1.04-1.08). The interaction of weight change during early infancy with BMI during childhood was significant for asthma (p < .01). Rapid weight gain in infancy was associated with lower risk of asthma in those with low BMI during childhood; had no association with asthma in those with normal BMI during childhood; and was associated increased asthma risk in those with high BMI during childhood-aHR 1.26 (95% CI 1.19 to 1.33) and aHR 1.33 (95% CI 1.12 to 1.56) compared with on-track and slow infant weight gain, respectively.

CONCLUSION

Low birth weight, high BMI during childhood and, in those with high childhood BMI, rapid weight gain during early infancy are associated with increased risk of childhood asthma.

Obesity-related biomarkers underlie a shared genetic architecture between childhood body mass index and childhood asthma

Obesity and asthma are both common diseases with high population burden worldwide. Recent genetic association studies have shown that obesity is associated with asthma in adults. The relationship between childhood obesity and childhood asthma, and the underlying mechanisms linking obesity to asthma remain to be clarified. In the present study, leveraging large-scale genetic data from UK biobank and several other data sources, we investigated the shared genetic components between body mass index (BMI, n = 39620) in children and childhood asthma (n_case = 10524, n_control = 373393). We included GWAS summary statistics for nine obesity-related biomarkers to evaluate potential biological mediators underlying obesity and asthma. We found a genetic correlation (Rg = 0.10, P = 0.02) between childhood BMI and childhood asthma, whereas the genetic correlation between adult BMI (n = 371541) and childhood asthma was null (Rg = -0.03, P = 0.21). Genomic structural equation modeling analysis further provided evidence that the genetic effect of childhood BMI on childhood asthma (standardized effect size 0.17, P = 0.009) was not driven by the genetic component of adult BMI. Bayesian colocalization analysis identified a shared causal variant rs12436181 that was mapped to gene AMN using gene expression data in lung tissue. Mendelian randomization showed that the odds ratio of childhood asthma for one standard deviation higher of childhood BMI was 1.13 (95% confidence interval: 0.96-1.34). A systematic survey of obesity-related biomarkers showed that IL-6 and adiponectin are potential biological mediators linking obesity and asthma in children. This large-scale genetic study provides evidence that unique childhood obesity pathways could lead to childhood asthma. The findings shed light on childhood asthma pathogenic mechanisms and prevention.

Early-life weight gain is associated with non-atopic asthma in childhood

Background

Previous studies suggest the association between early-life weight gain and asthma. It remains unclear whether early-life weight gain is associated with atopic or non-atopic asthma. This study aimed to investigate whether early-life weight gain is associated with atopic or non-atopic asthma.

Methods

Included in this study were 1343 singleton-birth children (761 boys, 57%) born between January 2010 and December 2011 participating in the Longitudinal Investigation of Global Health in Taiwanese Schoolchildren (LIGHTS) cohort were evaluated by a modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire and interviewed by pediatricians between July 1, 2016 and May 31, 2018 at the mean age of 6.4 years. Weight gain z-scores during the first 6, 12, and 18 months of life were classified into 4 groups: slow (below −0.67), on track (−0.67 to 0.67), rapid (0.67 to 1.28), and extremely rapid (above 1.28). The main outcomes were atopic and non-atopic asthma. Asthma was defined as having physician-diagnosed asthma and the presence of wheeze or asthma exacerbations in the last 12 months. Atopy was determined by Phadiatop Infant.

Results

The extremely rapid weight gain group of children during the first 6, 12, and 18 months of life was significantly associated with an increased risk of non-atopic asthma (adjusted odd ratio [AOR], 2.14, 95% confidence interval [CI], 1.01–4.53 for the first 6 months; AOR, 2.86, 95% CI, 1.34–6.14 for the first 12 months; AOR, 3.26, 95% CI 1.49–7.15 for the first 18 months) compared with the on track group. No significant association was found in atopic asthma. A sex-stratified analysis revealed the association of early-life weight gain with non-atopic asthma was statistically significant only in boys (AOR, 4.24, 95% CI, 1.44–12.50).

Conclusion

Extremely rapid weight gain during the first 6–18 months of life was significantly associated with 2.1- to 3.3-fold increased risk of non-atopic asthma, with a more pronounced risk found in boys.

Association of weight change patterns across adulthood with incident asthma: a retrospective cohort study

This study aimed to investigate the relationship between weight change patterns across adulthood and the risk of incident asthma later in life using data from the National Health and Nutrition Examination Survey (NHANES) 2001-2018. In this retrospective cohort study, asthma was defined by self-report questionnaires, and age at diagnosis was used to estimate the time of asthma onset. Based on BMI at 25 years old (young adulthood) and BMI at 10 years before the survey (middle adulthood), patterns of weight change were divided into five categories including stable normal, non-obese to obese, obese to non-obese, maximum overweight and stable obese. A total of 27,359 participants (female 13,582, 49.6%) were enrolled in this study and during a mean follow-up of 9.8 years, 1035 subjects occurred asthma. After adjusting for age, gender, race, education, family income and smoking status, participants changing from non-obese to obese, stable obese had significantly higher risks of incident asthma than those with normal weight during adulthood (HR1.70, 95% CI 1.35-2.15, P < 0.0001; HR 1.66, 95% CI 1.21-2.19 P = 0.0019, respectively). The findings suggested that maintaining normal weight during adulthood may be important for preventing incident asthma in later life.

An Overview of the Obese-Asthma Phenotype in Children

Asthma is the most common chronic disease in childhood. Overweight and obesity are included among the comorbidities considered in patients with difficult-to-treat asthma, suggesting a specific phenotype of the disease. Therefore, the constant increase in obesity prevalence in children and adolescents raises concerns about the parallel increase of obesity-associated asthma. The possible correlation between obesity and asthma has been investigated over the last decade by different authors, who suggest a complex multifactorial relationship. Although the particular non-eosinophilic endotype of obesity-related asthma supports the concept that high body weight precedes asthma development, there is ongoing debate about the direct causality of these two entities. A number of mechanisms may be involved in asthma in combination with obesity disease in children, including reduced physical activity, abnormal ventilation, chronic systemic inflammation, hormonal influences, genetics and additional comorbidities, such as gastroesophageal reflux and dysfunctional breathing. The identification of the obesity-related asthma phenotype is crucial to initiate specific therapeutic management. Besides the cornerstones of asthma treatment, lifestyle should be optimized, with interventions aiming to promote physical exercise, healthy diet, and comorbidities. Future studies should clarify the exact association between asthma and obesity and the mechanisms underlying the pathogenesis of these two related conditions with the aim to define personalized therapeutic strategies for asthma management in this population.

Trajectories of adiposity indicators and association with asthma and lung function in urban minority children

BACKGROUND

A relationship between adiposity and asthma has been described in some cohort studies, but little is known about trajectories of adiposity throughout early childhood among children at high risk for developing asthma in urban United States cities. Moreover, early life trajectories of adipokines that have metabolic and immunologic properties have not been comprehensively investigated.

OBJECTIVE

Our objective was to characterize trajectories of adiposity in a longitudinal birth cohort of predominately Black and Latinx children (n = 418) using several different repeated measures including body mass index (BMI) z score, bioimpedance analysis, leptin, and adiponectin in the first 10 years of life.

METHODS

In a longitudinal birth cohort of predominately Black and Latinx children, we used repeated annual measures of BMI, bioimpedance analysis (ie, percentage of body fat), leptin, and adiponectin to create trajectories across the first 10 years of life. Across those trajectories, we compared asthma diagnosis and multiple lung function outcomes, including spirometry, impulse oscillometry, and methacholine response.

RESULTS

Three trajectories were observed for BMI z score, bioimpedance analysis, and leptin and 2 for adiponectin. There was no association between trajectories of BMI, percentage of body fat, leptin, or adipokine and asthma diagnosis or lung function (P > .05).

CONCLUSIONS

Trajectories of adiposity were not associated with asthma or lung function in children at high risk for developing asthma. Risk factors related to geography as well as social and demographic factors unique to specific populations could explain the lack of association and should be considered in obesity and asthma studies.

Childhood asthma- pathogenesis and phenotypes

In the pathogenesis of asthma in children there is a pivotal role for a type 2 inflammatory response to early life exposures or events. Interactions between infections, atopy, genetic susceptibility, and environmental exposures (such as farmyard environment, air pollution, tobacco smoke exposure) influence the development of wheezing illness and the risk for progression to asthma. The immune system, lung function and the microbiome in gut and airways develop in parallel and dysbiosis of the microbiome may be a critical factor in asthma development. Increased infant weight gain and preterm birth are other risk factors for development of asthma and reduced lung function. The complex interplay between these factors explains the heterogeneity of asthma in children. Subgroups of patients can be identified as phenotypes based on clinical parameters, or endotypes, based on a specific pathophysiological mechanism. Paediatric asthma phenotypes and endotypes may ultimately help to improve diagnosis of asthma, prediction of asthma development and treatment of individual children, based on clinical, temporal, developmental or inflammatory characteristics. Unbiased, data-driven clustering, using a multidimensional or systems biology approach may be needed to better define phenotypes. The present knowledge on inflammatory phenotypes of childhood asthma has now been successfully applied in the treatment with biologicals of children with severe therapy resistant asthma, and it is to be expected that more personalized treatment options may become available.

Genes, environment, and developmental timing: New insights from translational approaches to understand early origins of respiratory diseases

Over the past decade, "omics" approaches have advanced our understanding of the molecular programming of the airways in humans. Several studies have identified potential molecular mechanisms that contribute to early life epigenetic reprogramming, including DNA methylation, histone modifications, microRNAs, and the homeostasis of the respiratory mucosa (epithelial function and microbiota). Current evidence supports the notion that early infancy is characterized by heightened susceptibility to airway genetic reprogramming in response to the first exposures in life, some of which can have life-long consequences. Here, we summarize and analyze the latest insights from studies that support a novel epigenetic paradigm centered on human maturational and developmental programs including three cardinal elements: genes, environment, and developmental timing. The combination of these factors is likely responsible for the functional trajectory of the respiratory system at the molecular, functional, and clinical levels.

Levels of Predominant Intestinal Microorganisms in 1 Month-Old Full-Term Babies and Weight Gain during the First Year of Life

The early life gut microbiota has been reported to be involved in neonatal weight gain and later infant growth. Therefore, this early microbiota may constitute a target for the promotion of healthy neonatal growth and development with potential consequences for later life. Unfortunately, we are still far from understanding the association between neonatal microbiota and weight gain and growth. In this context, we evaluated the relationship between early microbiota and weight in a cohort of full-term infants. The absolute levels of specific fecal microorganisms were determined in 88 vaginally delivered and 36 C-section-delivered full-term newborns at 1 month of age and their growth up to 12 months of age. We observed statistically significant associations between the levels of some early life gut microbes and infant weight gain during the first year of life. Classifying the infants into tertiles according to their Staphylococcus levels at 1 month of age allowed us to observe a significantly lower weight at 12 months of life in the C-section-delivered infants from the highest tertile. Univariate and multivariate models pointed out associations between the levels of some fecal microorganisms at 1 month of age and weight gain at 6 and 12 months. Interestingly, these associations were different in vaginally and C-section-delivered babies. A significant direct association between Staphylococcus and weight gain at 1 month of life was observed in vaginally delivered babies, whereas in C-section-delivered infants, lower Bacteroides levels at 1 month were associated with higher later weight gain (at 6 and 12 months). Our results indicate an association between the gut microbiota and weight gain in early life and highlight potential microbial predictors for later weight gain.

Infant body mass index trajectories and asthma and lung function

BACKGROUND

The impact of early rapid increase in body mass index (BMI) on asthma risk and subsequent lung function remains contentious, with limited prospective studies during a critical window for lung growth.

OBJECTIVE

Our aim was to investigate the associations between BMI trajectories in the first 2 years of life and adolescent asthma and lung function.

METHODS

Anthropometric data on 620 infants from the Melbourne Atopy Cohort Study were collected up to 18 times in the first 24 months of the study. BMI trajectories were developed by using group-based trajectory modeling. Associations between these trajectories and spirometry, fractional exhaled nitric oxide level, and current asthma status at 12 and/or 18 years of age were modeled by using multiple linear and logistic regression.

RESULTS

A total of 5 BMI trajectories were identified. Compared with those children with the "average" trajectory, the children belonging to the "early-low and catch-up" and "persistently high" BMI trajectories were at higher risk of asthma at the age of 18 years (odds ratios = 2.2 [95% CI = 1.0-4.8 and 2.4 [95% CI = 1.1-5.3], respectively). These trajectories were also associated with a lower ratio of FEV₁ to forced vital capacity and a higher fractional exhaled nitric oxide levels at age 18 years. In addition, children belonging to the persistently low trajectory had lower FEV₁ (β = -183.9 mL [95% CI = -340.9 to -26.9]) and forced vital capacity (β = -207.8 mL [95% CI = -393.6 to -22.0]) values at the age of 18 years.

CONCLUSION

In this cohort, the early-low and catch-up and persistently high trajectories were associated with asthma and obstructive lung function pattern in adolescence. Having a persistently low BMI at an early age was associated with a restrictive pattern. Thus, maintenance of normal growth patterns may lead to improved adolescent respiratory health.

Recurrent Wheezing and Asthma After Respiratory Syncytial Virus Bronchiolitis

Background: Respiratory syncytial virus (RSV) is the most common pathogen of acute bronchiolitis in children, which sometimes triggers the development of recurrent wheezing and increases the risk of childhood asthma. Methods: We enrolled 425 children who were diagnosed with RSV-infected bronchiolitis at the department of pulmonology, Children's Hospital Zhejiang University School of Medicine in 2011. Long-term follow-up was performed to explore the consequence of bronchiolitis on subsequent recurrent wheezing and asthma. Results: Of 425 patients, 266 cases completed the entire follow-up, the mean age of onset was 4.9 (3.3) months, and the male-to-female ratio was 2.5. The mean birth weight of all patients was 3.22 (0.63) kg, and the number of patients who had a history of cesarean section was 148. According to the outcome of follow-up, 36 were in the recurrent wheezing (RW) group, 65 were in the asthma (AS) group, and the remaining 165 were in the completely recovered (CR) group. The age of onset was older and the birth weights were higher in the AS group than those in the CR group (P < 0.05). And the higher proportion of cesarean sections was higher in the RW group than that in the CR group (P < 0.05). Furthermore, we found a remarkable increasing of serum IgE in the AS groups than that in the CR group (P < 0.01). Multiple logistic regression analysis showed that the cesarean section was the risk factor for the development of recurrent wheezing and the higher birth weight was the risk factor for the development of asthma. Conclusion: RSV bronchiolitis might increase the incidence of recurrent wheezing and asthma. Allergic constitution was an important prerequisite for the occurrence of asthma, and related risk factor such as cesarean section can only increase recurrent wheezing to a certain extent within a certain period of time. And we also find higher birth weight and older onset age for those who develop asthma, which should be verified in the future.

How to apply the personalized medicine in obesity-associated asthma?

INTRODUCTION

Obesity-associated asthma (OA) is frequently severe, with an increased rate of hospitalizations, numerous comorbidities and low response to corticosteroids. Despite progress in applying for personalized medicine in asthma, no specific recommendations exist for the management of OA.

AREAS COVERED

The aim of this review is to summarize recent data about the relationship obesity-asthma, describe clinical characteristics, potential mechanisms involved and possible therapeutic interventions to improve OA outcomes. Extensive research in the PubMed was performed using the following terms: "asthma and obesity" and "obese asthma" in combination with "phenotypes", "airway inflammation", "biomarkers", "lung function", "weight loss", "lifestyle interventions", "therapies" Currently two phenotypes are described. Early-onset atopic asthma is conventional allergic asthma aggravated by the pro-inflammatory properties of adipose tissue in excess, while late-onset non-atopic asthma is due to airway dysfunction as a consequence of the chronic lung compression caused by the obese chest walls. Previous data showed that different therapeutic strategies used in weight loss have a positive impact on OA outcomes.

EXPERT OPINION

The presence of a multidisciplinary team (chest physician, nutritionist, exercise physiologist, physiotherapist, psychologist, bariatric surgeon) and the collaboration between different specialists are mandatory to optimize the management and to apply the personalized medicine in OA.

Association of pediatric obesity and asthma, pulmonary physiology, metabolic dysregulation, and atopy; and the role of weight management

Introduction: Obesity affects about 40% of US adults and 18% of children. Its impact on the pulmonary system is best described for asthma. Areas covered: We reviewed the literature on PubMed and Google Scholar databases and summarize the effect of obesity, its associated metabolic dysregulation and altered systemic immune responses, and that of weight gain and loss on pulmonary mechanics, asthma inception, and disease burden. We include a distinct approach for diagnosing and managing the disease, including pulmonary function deficits inherent to obesity-related asthma, in light of its poor response to current asthma medications. Expert opinion: Given the projected increase in obesity, obesity-related asthma needs to be addressed now. Research on the contribution of metabolic abnormalities and systemic immune responses, intricately linked with truncal adiposity, and that of lack of atopy, to asthma disease burden, and pulmonary function deficits among obese children is fairly consistent. Since current asthma medications are more effective for atopic asthma, investigation for atopy will guide management by distinguishing asthma responsive to current medications from the non-responsive disease. Future research is needed to elucidate mechanisms by which obesity-mediated metabolic abnormalities and immune responses cause medication non-responsive asthma, which will inform repurposing of medications and drug discovery.

Association between overweight or obesity and the risk for childhood asthma and wheeze: An updated meta-analysis on 18 articles and 73 252 children

BACKGROUND

Overweight or obesity is increasingly recognized as a possible risk factor for childhood asthma.

OBJECTIVES

We aimed to meta-analyse the association between overweight or obesity and the risk for childhood asthma and wheeze and meanwhile explore potential causes of between-study heterogeneity.

METHODS

Literature search, study selection, and data extraction were performed independently and in duplicate. Data were analysed by STATA software.

RESULTS

Eighteen articles and 73 252 children were analysed. In overall analyses, there was a significant association between overweight or obesity and the risk for childhood asthma (odds ratio [OR] = 1.30; 95% confidence interval [CI], 1.23-1.39; P < 0.001) and wheeze (OR = 1.90; 95% CI, 1.38-2.63; P < 0.001), with none/marginal publication bias as revealed by the Egger test (P = 0.938/0.038), respectively. Subgroup analyses showed that children with obesity (OR = 1.40; 95% CI, 1.29-1.52) were more likely to have asthma than children with overweight (OR = 1.22; 95% CI, 1.14-1.31), and in children with overweight or obesity, girls (OR = 1.34; 95% CI, 1.16-1.56) were more likely to have asthma than boys (OR = 1.27; 95% CI, 1.15-1.40).

CONCLUSIONS

Our findings indicate that overweight or obesity is a significant risk factor for childhood asthma and wheeze and in children with overweight or obesity, the risk is more evident in girls than in boys.

Obesity and severe asthma

Obesity is an important global health issue for both children and adults. Obesity increases the prevalence and incidence of asthma and also increases the risk for severe asthma. Here we describe the features of severe asthma phenotypes for which obesity is a defining characteristic, including steroid resistance, airway inflammation, and co-morbidities. We also review current concepts regarding the mechanistic basis for the impact of obesity in severe asthma, including possible roles for vitamin D deficiency, systemic inflammation, and the microbiome. Finally, we describe data indicating a role for diet, weight loss, and exercise in the treatment of severe asthma with obesity. Better understanding of the mechanistic basis for the role of obesity in severe asthma could lead to new therapeutic options for this population.