Controversial role of pets in the development of atopy in children

Environmental exposures in early-life and general health in childhood

BACKGROUND

Early-life environmental exposures are suspected to be involved in the development of chronic diseases later in life. Most studies conducted so far considered single or few exposures and single-health parameter. Our study aimed to identify a childhood general health score and assess its association with a wide range of pre- and post-natal environmental exposures.

METHODS

The analysis is based on 870 children (6-12 years) from six European birth cohorts participating in the Human Early-Life Exposome project. A total of 53 prenatal and 105 childhood environmental factors were considered, including lifestyle, social, urban and chemical exposures. We built a general health score by averaging three sub-scores (cardiometabolic, respiratory/allergy and mental) built from 15 health parameters. By construct, a child with a low score has a low general health status. Penalized multivariable regression through Least Absolute Shrinkage and Selection Operator (LASSO) was fitted in order to identify exposures associated with the general health score.

FINDINGS

The results of LASSO show that a lower general health score was associated with maternal passive and active smoking during pregnancy and postnatal exposure to methylparaben, copper, indoor air pollutants, high intake of caffeinated drinks and few contacts with friends and family. Higher child's general health score was associated with prenatal exposure to a bluespace near residency and postnatal exposures to pets, cobalt, high intakes of vegetables and more physical activity. Against our hypotheses, postnatal exposure to organochlorine compounds and perfluorooctanoate were associated with a higher child's general health score.

CONCLUSION

By using a general health score summarizing the child cardiometabolic, respiratory/allergy and mental health, this study reinforced previously suspected environmental factors associated with various child health parameters (e.g. tobacco, air pollutants) and identified new factors (e.g. pets, bluespace) warranting further investigations.

[Are pets, dog or cat, a risk or a protector factor for the development or exacerbation of asthma? Systematic review of systematic reviews]

BACKGROUND

Preliminary studies have shown conflicting results on the association between exposure to pets (cat or dog) and asthma. Previous scientific evidence has not been clear to determine if avoiding or allowing the exposure to pets could prevent, improve, or worsen the development of asthma and its symptoms.

OBJECTIVE

To try to explain the controversial relationship between exposure to pets (dog or cat) and its effect on the development of asthma or the exacerbation of symptoms in both children and adults.

METHODS

A standardized search in five electronic databases by an independent reviewer was carried out. The final sample of studies included in the overview of systematic reviews was screened and synthesized through a master table. A narrative description of the results was made.

RESULTS

This systematic review of systematic found determined principally that having a cat could be a risk factor and having a dog a protective factor in the development of asthma. However, early exposure to both cats and dogs (before the age of two) reduces the probability of asthma symptoms and wheezing in the school years. Additionally, having antecedents of sensibilization to pets allergen could be a risk factor to exacerbate asthma in both children and adults.

Prevalence of Asthma and Its Associating Environmental Factors among 6-12-Year-Old Schoolchildren in a Metropolitan Environment-A Cross-Sectional, Questionnaire-Based Study

We aimed to evaluate the prevalence of asthma and its associating environmental factors within a 6–12-year-old population. A cross-sectional, questionnaire-based study was conducted in primary schools located in the capital of Hungary; 3836 eligible parent-reported questionnaires were evaluated. Besides the International Study of Asthma and Allergies in Childhood (ISAAC) phase three core questions for asthma, the survey also assessed various potential risk factors. We introduced the umbrella term cumulative asthma as the union of physician-diagnosed asthma and current wheezing to estimate the lifetime prevalence of asthma. Current wheezing and physician-diagnosed asthma showed a frequency of 9.5% and 6.3%, respectively. They contributed to a cumulative asthma prevalence of 12.6% among the sampled population, with a girl-boy percentage of 37.4% to 62.6%. Air-pollution and weedy areas were associated with greater risk for asthma, while a suburban residence showed lesser odds. Indoor smoking, visible mold, and keeping a dog were defined as risk factors for asthma, while the presence of plants in the bedroom and pet rodents were associated with lower odds ratios. The consumption of fast food, beverages containing additives and margarine were significantly higher in asthmatics, while we found frequent sport activity and cereal intake associated with lower odds ratios for asthma. In this urban environment, we identified an increased asthma prevalence compared to some previously published studies, but the cross-sectional design and the different methodology did not permit us to draw timeframe-dependent conclusions.

Human-Animal Interaction and Perinatal Mental Health: A Narrative Review of Selected Literature and Call for Research

There is a paucity of research exploring how relationships with household pets may impact maternal mental health. We are unaware of any study to date that has examined associations between individuals' relationships with their pets and psychological adjustment in the perinatal period. Using a biobehavioral lens, this paper provides a narrative overview of the literature on perinatal mental health and human-animal interaction (HAI). We focus on the role of social relationships, stress, and stress reduction in relation to perinatal mental health; the role of HAI in perceptions of social support, stressors, and stress reduction; and gaps in empirical knowledge concerning the role of HAI in perinatal mental health. Finally, we integrate contemporary biobehavioral models of perinatal mental health and HAI (i.e., Comprehensive Model of Mental Health during the Perinatal Period and the HAI-HPA Transactional Model) to propose a new conceptual framework that depicts ways in which HAI during the perinatal period may influence maternal and child health and wellbeing. To our knowledge, this is the first paper to consider the role of HAI in biobehavioral responses and mental health during the perinatal period. We conclude with recommendations for future research and improved perinatal care.

The Concerns, Difficulties, and Stressors of Caring for Pets during COVID-19: Results from a Large Survey of U.S. Pet Owners

Pets may be a positive presence for their owners during the Coronavirus Disease 2019 (COVID-19) pandemic. However, it is pertinent to identify the hardships associated with pet ownership. We conducted a large-scale survey of U.S. pet owners (n = 2254) in spring and summer 2020 to assess the ways that relationships with pets impacted life during COVID-19. We used thematic analysis to analyze 3671 open-ended responses to three prompts. Reported concerns fell into three major categories: (1) pet-focused (meeting needs of pets; procuring supplies; accessing veterinary care; new and emerging behavioral issues; fate of the pet if owner becomes ill; general safety and well-being), (2) human-focused (issues with working from home; well-being and mental health; balancing responsibilities), and (3) household-focused (disease spread; economic issues). Quantitative analyses showed that the owner's strength of attachment to their pet, economic resources, and relationship status were associated with the types of concerns expressed. Results from this study indicate that pet owners experienced unique hardships related to changes in everyday life from the COVID-19 pandemic. These hardships should be considered alongside the potential benefits found in other studies in order to manage pet owner expectations, prevent pet relinquishment, and more fully understand multifaceted human-companion animal relationships.

Risk factors for atopic and nonatopic asthma in Puerto Rican children

BACKGROUND

Little is known about the risk factors for atopic and nonatopic asthma among children in Puerto Rico. We aimed to identify modifiable risk factors for atopic and nonatopic asthma in this vulnerable population.

METHODS

Case-control study of children with (n = 305) and without (n = 327) asthma in San Juan (Puerto Rico). Asthma was defined as physician-diagnosed asthma and wheeze in the previous year. Atopic asthma (n = 210) was defined as asthma and greater than or equal to one positive IgE to aero-allergens. Nonatopic asthma (n = 95) was defined as asthma and no positive IgE to the allergens tested. Logistic regression was used for the multivariable analysis of atopic and nonatopic asthma.

RESULTS

In a multivariable analysis, body mass index (BMI) z score, prematurity, parental asthma, lifetime exposure to gun violence, and having a bird in the child's home were associated with increased odds of atopic asthma, while each one-point increment in a dietary score (range: -2 [least healthy diet] to +2 [healthiest diet]) was associated with 37% reduced odds of atopic asthma (95% confidence interval [CI] = 0.48-0.81; P < .01). In a separate multivariable analysis, parental asthma, early-life second-hand smoke (SHS) exposure, and daycare attendance in the first year of life were significantly associated with increased odds of nonatopic asthma, while each one-point increment in the dietary score was associated with 42% reduced odds of nonatopic asthma (95% CI = 0.45-0.76; P < .01).

CONCLUSIONS

We have identified potentially modifiable risk factors for atopic asthma (eg, BMI and gun violence), nonatopic asthma (eg, early-life SHS and daycare attendance), or both (eg, an unhealthy diet) in Puerto Rican children.

Early exposure to cats, dogs and farm animals and the risk of childhood asthma and allergy

BACKGROUND

Synergistic role of exposure to cats, dogs, and farm animals during infancy on the risk of childhood asthma and allergy remains unknown.

OBJECTIVES

To investigate independent and synergistic associations between exposure to indoor pets and farm animals during infancy and the risk of asthma and allergy by age 5.

METHODS

We studied 3781 children participating in the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Nutrition Study. At age 5, a validated version of the International Study of Asthma and Allergies in Childhood questionnaire was administered to collect information on asthma and allergic disease, and exposure to indoor pets and farm animals during the first year of life. Allergen-specific IgE antibodies were analyzed from serum samples. Statistical analyses employed Cox proportional hazards and logistic regression.

RESULTS

Having a dog in the house was inversely associated with the risk of asthma (HR 0.60; 95% CI, 0.38-0.96), allergic rhinitis (OR 0.72; 95% CI, 0.53-0.97), and atopic sensitization (OR 0.77; 95% CI, 0.63-0.96). Having a cat was associated with a decreased risk of atopic eczema (OR 0.68; 95% CI, 0.51-0.92). Farm animals were neither independently nor in synergy with indoor pets associated with the outcomes.

CONCLUSION

Having a dog or cat in the house during the first year of life may protect against childhood asthma and allergy. We did not find a synergistic association between cat, dog, and farm animal exposure on the risk of childhood asthma and allergy. Future research should identify specific causative exposures conferred by indoor pets and whether they could be recommended for allergy prevention.

Pre-natal and post-natal exposure to pet ownership and lung function in children: The Seven Northeastern Cities Study

To evaluate the association between pre-natal and post-natal exposure to pet ownership and lung function in children, a cross-sectional study named Seven Northeastern Cities (SNEC) study was conducted. In this study, children's lung function including the forced expiratory volume in 1 second (FEV₁ ), forced vital capacity (FVC), maximal mid-expiratory flow (MMEF), and peak expiratory flow (PEF) were measured by spirometers, and pet ownership situations were collected by questionnaire. Analyzed by multiple logistic regression and generalized linear modeling, we found that for all subjects, pet exposure in the first 2 years of life was significantly associated with lung function impairment of FVC<85% predicted (adjusted odds ratio [aOR]=1.28; 95% confidence interval [CI]: 1.01, 1.63). For current pet exposure, the increased odds of lung function impairment ranged from 35% (aOR=1.35; 95%CI: 1.12, 1.62) for FVC<85% predicted to 57% (aOR=1.57; 95%CI: 1.29, 1.93) for FEV₁ <85% predicted. The in utero exposure was not related to lung function impairment. Compared with other pets, higher odds were observed among children with dogs. When stratified by gender, girls with current pet exposure were more likely to have lung function impairment than boys. It implies self-reported exposures to pets were negatively associated with lung function among the children under study.

Exploring the associations between parent-reported biological indoor environment and airway-related symptoms and allergic diseases in children

OBJECTIVES

Asthma and allergic rhinitis are diseases which require special attention in childhood. Risk factors for these diseases are manifold and include environmental factors. Previous studies have shown associations between indoor mould and respiratory diseases in children. Besides indoor mould, organic waste storage, potted plants, pets and crowding could influence the microbial indoor environment at home and the respiratory health of children. Our aim was therefore to explore the associations of these factors with airway-related symptoms and respiratory diseases in preschoolers.

METHODS

In this cross-sectional study we evaluated data based on parent-questionnaires regarding the health of their children from the 2014/2015 Health Monitoring Units (GME) in Bavaria. Bivariate and multivariate odds ratios (OR) with 95% confidence intervals (95%-CI) were calculated with logistic regression to explore associations between exposures (visible mould, organic waste storage, potted plants, pets and crowding) and outcome variables (doctor diagnosed allergic rhinitis with symptoms in the last 12 months, doctor diagnosed asthma with symptoms in the last 12 months, 12 month prevalence of symptoms such as dry cough at night without a cold, wheeze, wheeze attacks and allergic rhinitis symptoms).

RESULTS

We analysed data from 4732 children (response rate 56.7%) with a mean age of 5.3 years. Visible mould was present in 4.7% of all households and associated with doctor diagnosed asthma with symptoms in the last 12 months [aOR 2.16 (95%-CI 1.01-4.63)], wheeze in the last 12 months [aOR 1.60 (95%-CI 1.0-2.50)] and allergic rhinitis symptoms in the last 12 months [aOR 1.75 (95%-CI 1.07-2.87)]. Crowding was associated with dry cough at night without a cold in the last 12 months [aOR 1.71 (95%-CI 1.42-2.05). The other indoor factors showed no association with respiratory health of the children.

CONCLUSION

Our results, in line with previous studies, showed positive associations between visible mould at home and airway-related symptoms and allergic diseases in children irrespective of the effect of the other considered indoor exposures. Despite the low prevalence of mould exposure in our study population, our results suggest intervention should be taken for those who do have visible mould exposure at home.

The environment, epigenome, and asthma

Asthma prevalence has been on the increase, especially in North America compared with other continents. However, the prevalence of asthma differs worldwide, and in many countries the prevalence is stable or decreasing. This highlights the influence of environmental exposures, such as allergens, air pollution, and the environmental microbiome, on disease etiology and pathogenesis. The epigenome might provide the unifying mechanism that translates the influence of environmental exposures to changes in gene expression, respiratory epithelial function, and immune cell skewing that are hallmarks of asthma. In this review we will introduce the concept of the environmental epigenome in asthmatic patients, summarize previous publications of relevance to this field, and discuss future directions.

Breastfeeding and perinatal exposure, and the risk of asthma and allergies

PURPOSE OF REVIEW

Exposures during the perinatal period, a phase of rapid development, may have a profound and sustained effect on disease risk. In particular, perinatal exposures may influence the development and maturation of the infant immune system and the risk of allergic disease. We aimed to summarize the current literature on perinatal exposures and the risk of asthma and allergic disease

RECENT FINDINGS

Increased risk of offspring wheeze or asthma was found for: maternal obesity and hypertension during pregnancy; febrile illness, gynaecological, and viral respiratory infections in pregnancy; exposure to bisphenol A and phthalates in pregnancy and childhood; exposure to smoking in utero; low birth weight; caesarean section and neonatal hyperbilirubinaemia. Reduced risk of offspring atopic eczema was found for hookworm infection in pregnancy and reduced risk of offspring wheeze was associated with increased pregnancy dietary intake of vitamin E and zinc. Higher levels of selenium in pregnancy were associated with less risk of asthma in genetically susceptible offspring. Early life pet ownership was associated with a decrease in atopic asthma but an increase in nonatopic asthma risk.

SUMMARY

A diverse range of exposures were associated with allergic disease risk, highlighting the susceptibility of children during the perinatal period. Clinicians should reinforce public health messages concerning maternal obesity, smoking, and breastfeeding. The infant gut microbiome is emerging as an important hypothesis, which may mediate the relationship between many perinatal exposures and allergic disease.

Particularities of allergy in the Tropics

Allergic diseases are distributed worldwide and their risk factors and triggers vary according to geographical and socioeconomic conditions. Allergies are frequent in the Tropics but aspects of their prevalence, natural history, risk factors, sensitizers and triggers are not well defined and some are expected to be different from those in temperate zone countries. The aim of this review is to investigate if allergic diseases in the Tropics have particularities that deserve special attention for research and clinical practice. Such information will help to form a better understanding of the pathogenesis, diagnosis and management of allergic diseases in the Tropics. As expected, we found particularities in the Tropics that merit further study because they strongly affect the natural history of common allergic diseases; most of them related to climate conditions that favor permanent exposure to mite allergens, helminth infections and stinging insects. In addition, we detected several unmet needs in important areas which should be investigated and solved by collaborative efforts led by the emergent research groups on allergy from tropical countries.

Associations of TNFα -308G>A, TNFα -238G>A, IL-1α -889C>T and IL-10 -1082G>A Genetic Polymorphisms with Atopic Diseases: Asthma, Rhinitis and Dermatitis

BACKGROUND

Polymorphisms of cytokine genes are an interesting focus for association studies involving atopic diseases due to their role in immune cell communications during inflammation. The aim of this study was to investigate associations of TNFα -308G>A, TNFα -238G>A, IL-1α -889C>T and IL-10 -1082G>A polymorphisms with atopic diseases with adjustment for confounding lifestyle and environmental factors.

METHODS

This study was performed on 356 Croatian students. The diagnosis of atopic asthma, atopic rhinitis and atopic dermatitis was based on symptoms reported by the modified International Study of Asthma and Allergies in Childhood questionnaire and a positive skin prick test (SPT) to at least one common inhalatory allergen. Genetic polymorphisms were genotyped using the polymerase chain reaction-based technique. The influence of personal (gender, body mass index, parental history of atopic disease), lifestyle (cigarette smoking, pet ownership) and environmental (urban/rural residency, residency in continental/Mediterranean region) factors reported in the questionnaire was investigated by univariate and multivariate analysis.

RESULTS

Compared to the control subjects, univariate analysis showed a significant negative association of the TNFα -308G>A polymorphism with atopic asthma, atopic dermatitis, asthma and skin symptoms and positive SPT. These observations were confirmed in a multivariate model only for atopic dermatitis and skin symptoms (atopic dermatitis: OR = 0.27; 95% CI 0.07-1.00; p = 0.050; skin symptoms: OR = 0.29; 95% CI 0.10-0.83; p = 0.021).

CONCLUSIONS

The results indicate a protective role of TNFα -308G>A genetic polymorphisms regarding atopic dermatitis and skin symptoms even after controlling for personal, lifestyle and environmental factors. Further studies are needed to elucidate the molecular patterns of this association in atopic dermatitis and other chronic inflammatory skin disorders.

In utero exposure to pets is associated with asthma and wheezing in Mexican American children

OBJECTIVE

To examine the associations of in utero and early life exposure to cats/dogs and birds with the risk of lifetime doctor-diagnosed asthma and other respiratory conditions in a sample of Mexican American (MA) children 4-18 years of age.

METHODS

This study is a population-based cross-sectional investigation of 1816 MA children. We conducted multiple logistic models examining the relationship of asthma and wheezing with exposures to cats/dogs and birds in utero, infancy and at the time of the survey adjusted for country of birth, family history of asthma/allergies, antibiotics use in infancy and other covariates.

RESULTS

In adjusted analyses, in utero exposure to cats/dogs and birds jointly was associated with increased odds of asthma (adjusted odds ratio (aOR): 2.89; 95% confidence interval (CI): 1.34-6.23), ever wheezing (aOR: 1.96; 95% CI: 1.11-3.46) and current exercise-induced wheezing (aOR: 3.16; 95% CI: 1.27-7.85) compared to children not exposed to these pets in utero. Children who were exposed to both cats/dogs and birds in utero had an elevated, albeit statistically non-significant, odds of current wheezing. Exposures in infancy and at the time of the survey to cats/dogs and birds were not associated with asthma or wheezing.

CONCLUSIONS

In utero exposure to pets might be associated with an increased risk of asthma and respiratory conditions in a sample of non-affluent MA children.

Clinical practice guideline: Allergic rhinitis

OBJECTIVE

Allergic rhinitis (AR) is one of the most common diseases affecting adults. It is the most common chronic disease in children in the United States today and the fifth most common chronic disease in the United States overall. AR is estimated to affect nearly 1 in every 6 Americans and generates $2 to $5 billion in direct health expenditures annually. It can impair quality of life and, through loss of work and school attendance, is responsible for as much as $2 to $4 billion in lost productivity annually. Not surprisingly, myriad diagnostic tests and treatments are used in managing this disorder, yet there is considerable variation in their use. This clinical practice guideline was undertaken to optimize the care of patients with AR by addressing quality improvement opportunities through an evaluation of the available evidence and an assessment of the harm-benefit balance of various diagnostic and management options.

PURPOSE

The primary purpose of this guideline is to address quality improvement opportunities for all clinicians, in any setting, who are likely to manage patients with AR as well as to optimize patient care, promote effective diagnosis and therapy, and reduce harmful or unnecessary variations in care. The guideline is intended to be applicable for both pediatric and adult patients with AR. Children under the age of 2 years were excluded from the clinical practice guideline because rhinitis in this population may be different than in older patients and is not informed by the same evidence base. The guideline is intended to focus on a limited number of quality improvement opportunities deemed most important by the working group and is not intended to be a comprehensive reference for diagnosing and managing AR. The recommendations outlined in the guideline are not intended to represent the standard of care for patient management, nor are the recommendations intended to limit treatment or care provided to individual patients.

ACTION STATEMENTS

The development group made a strong recommendation that clinicians recommend intranasal steroids for patients with a clinical diagnosis of AR whose symptoms affect their quality of life. The development group also made a strong recommendation that clinicians recommend oral second-generation/less sedating antihistamines for patients with AR and primary complaints of sneezing and itching. The panel made the following recommendations: (1) Clinicians should make the clinical diagnosis of AR when patients present with a history and physical examination consistent with an allergic cause and 1 or more of the following symptoms: nasal congestion, runny nose, itchy nose, or sneezing. Findings of AR consistent with an allergic cause include, but are not limited to, clear rhinorrhea, nasal congestion, pale discoloration of the nasal mucosa, and red and watery eyes. (2) Clinicians should perform and interpret, or refer to a clinician who can perform and interpret, specific IgE (skin or blood) allergy testing for patients with a clinical diagnosis of AR who do not respond to empiric treatment, or when the diagnosis is uncertain, or when knowledge of the specific causative allergen is needed to target therapy. (3) Clinicians should assess patients with a clinical diagnosis of AR for, and document in the medical record, the presence of associated conditions such as asthma, atopic dermatitis, sleep-disordered breathing, conjunctivitis, rhinosinusitis, and otitis media. (4) Clinicians should offer, or refer to a clinician who can offer, immunotherapy (sublingual or subcutaneous) for patients with AR who have inadequate response to symptoms with pharmacologic therapy with or without environmental controls. The panel recommended against (1) clinicians routinely performing sinonasal imaging in patients presenting with symptoms consistent with a diagnosis of AR and (2) clinicians offering oral leukotriene receptor antagonists as primary therapy for patients with AR. The panel group made the following options: (1) Clinicians may advise avoidance of known allergens or may advise environmental controls (ie, removal of pets; the use of air filtration systems, bed covers, and acaricides [chemical agents formulated to kill dust mites]) in patients with AR who have identified allergens that correlate with clinical symptoms. (2) Clinicians may offer intranasal antihistamines for patients with seasonal, perennial, or episodic AR. (3) Clinicians may offer combination pharmacologic therapy in patients with AR who have inadequate response to pharmacologic monotherapy. (4) Clinicians may offer, or refer to a surgeon who can offer, inferior turbinate reduction in patients with AR with nasal airway obstruction and enlarged inferior turbinates who have failed medical management. (5) Clinicians may offer acupuncture, or refer to a clinician who can offer acupuncture, for patients with AR who are interested in nonpharmacologic therapy. The development group provided no recommendation regarding the use of herbal therapy for patients with AR.

Role of TLR4 C>1196T (Thr399Ile) and TLR4 A>896G (Asp299Gly) polymorphisms in a North Indian population with asthma: a case-control study

Toll-like receptor 4 (TLR4) is the most important TLR among the pattern recognition receptors which recognizes lipopolysaccharide of gram-negative bacteria. They identify a highly conserved structure of microbes called pathogen-associated molecular patterns and activate immune and inflammatory responses that have been shown to be involved in the pathogenesis of asthma. The role of TLR4 gene polymorphisms in asthma was detected in a total of 964 individuals, including 483 healthy controls and 481 asthma patients from a North Indian population. The genotyping was carried out using polymerase chain reaction-restriction fragment length polymorphism method. Statistical analysis revealed that the heterozygous genotype as well as the mutant (T) allele of the TLR4 C>1196T (Thr399Ile) polymorphism shows resistance towards asthma with OR = 0.70, 95% CI (0.49-0.99), P corrected value = 0.046 and OR = 0.72, 95% CI (0.52-0.98), P corrected value = 0.039, respectively. However, no association was found between the TLR4 A>896G (Asp299Gly) polymorphism and asthma patients (P > 0.05). This is the first study conducted in India conferring TLR4 (Thr399Ile) polymorphism resistance towards asthma, while lack of association was found between TLR4 (Asp299Gly) polymorphism and asthma in the studied North Indian population.

Age at onset of asthma and allergen sensitization early in life

BACKGROUND

Epidemiological evidence indicates that the age at onset of asthma and allergen sensitization in early life is decreasing in people from Western countries. To explore latent trends, we conducted a retrospective examination of the age at onset of asthma and specific IgE antibodies against inhalant allergens in Japanese asthmatic children.

METHODS

We conducted a case series study of 103 consecutive children with atopic type of asthma (aged 2 years to 16 years, mean age 9.4 ± 3.4 years). Diagnoses of asthma and allergic rhinitis were defined according to Japanese guidelines. The onset of asthma and allergic rhinitis was also defined as any report of asthma and allergic rhinitis confirmed by a physician. Allergen sensitization was evaluated as specific serum IgE levels for 9 common inhalant allergens in peripheral blood. Atopic type of asthma was defined as a being positive for at least one aeroallergen.

RESULTS

Mean age at asthma onset was 2.3 ± 1.9 years, which is slightly lower than that of previous reports, including those published in Japan. A high prevalence rate of up to 80% was found for perennial antigens including Dermatophagoides spp. and house dust, as reported previously. Notably, some of the children aged at 1 year tested positive for these allergens.

CONCLUSIONS

The age at onset of asthma seems to be decreasing in comparison with previous reports. Furthermore, the age at onset of allergen sensitization against inhalant allergens appears to follow this trend.

Prevalence, severity and risk factors of asthma, rhinitis and eczema in a large group of Chinese schoolchildren

BACKGROUND

There is a lack of information on the prevalence, severity and risk factors of asthma, rhinitis and eczema in Chinese children.

OBJECTIVE

To establish baseline data for a major longitudinal study of factors affecting asthma, rhinitis and eczema in a large group of children from the industrialized city of Shijiazhuang, China.

METHODS

We used the International Study of Asthma and Allergies in Childhood questionnaire and studied 10 338 children, ages 6-18, from Shijiazhuang.

RESULTS

The prevalence of childhood asthma, rhinitis and eczema is 1.2%, 13.5% and 11.8%, respectively. Boys had higher prevalence of these conditions than girls and younger children had higher prevalence of asthma and eczema but lower prevalence of rhinitis than older children. Breastfed children had lower prevalence of asthma and rhinitis, but not eczema, than non-breastfed children. Overweight children had higher prevalence of asthma and rhinitis than those who were not overweight. Children exposed to paternal smoking had higher prevalence of rhinitis and eczema than those not exposed; children exposed to pets had higher prevalence of asthma and rhinitis than those not exposed.

CONCLUSIONS

The prevalence of asthma in this study group is low, but the prevalence of rhinitis is high, and could be considered a major public health problem. The prevalence of asthma, rhinitis and eczema is generally higher in boys and younger children generally have higher prevalence of asthma and eczema but lower prevalence of rhinitis. Exposure to pets is a risk factor for rhinitis, being overweight is a risk factor for asthma and rhinitis, and exposure to parental smoking is a risk factor for asthma, rhinitis and eczema in these children.

High prevalence of asthma symptoms in Warao Amerindian children in Venezuela is significantly associated with open-fire cooking: a cross-sectional observational study

Background

The International Study on Asthma and Allergies in Childhood (ISAAC) reported a prevalence of asthma symptoms in 17 centers in nine Latin American countries that was similar to prevalence rates reported in non-tropical countries. It has been proposed that the continuous exposure to infectious diseases in rural populations residing in tropical areas leads to a relatively low prevalence of asthma symptoms. As almost a quarter of Latin American people live in rural tropical areas, the encountered high prevalence of asthma symptoms is remarkable. Wood smoke exposure and environmental tobacco smoke have been identified as possible risk factors for having asthma symptoms.

Methods

We performed a cross-sectional observational study from June 1, 2012 to September 30, 2012 in which we interviewed parents and guardians of Warao Amerindian children from Venezuela. Asthma symptoms were defined according to the ISAAC definition as self-reported wheezing in the last 12 months. The associations between wood smoke exposure and environmental tobacco smoke and the prevalence of asthma symptoms were calculated by means of univariate and multivariable logistic regression analyses.

Results

We included 630 children between two and ten years of age. Asthma symptoms were recorded in 164 of these children (26%). The prevalence of asthma symptoms was associated with the cooking method. Children exposed to the smoke produced by cooking on open wood fires were at higher risk of having asthma symptoms compared to children exposed to cooking with gas (AOR 2.12, 95% CI 1.18 - 3.84). Four percent of the children lived in a household where more than ten cigarettes were smoked per day and they had a higher risk of having asthma symptoms compared to children who were not exposed to cigarette smoke (AOR 2.69, 95% CI 1.11 - 6.48).

Conclusion

Our findings suggest that children living in rural settings in a household where wood is used for cooking or where more than ten cigarettes are smoked daily have a higher risk of having asthma symptoms.