Asthma management and control in children, adolescents, and adults in 25 countries: a Global Asthma Network Phase I cross-sectional study

BACKGROUND

Asthma is one of the most common non-communicable diseases globally. This study aimed to assess asthma medicine use, management plan availability, and disease control in childhood, adolescence, and adulthood across different country settings.

METHODS

We used data from the Global Asthma Network Phase I cross-sectional epidemiological study (2015-20). A validated, written questionnaire was distributed via schools to three age groups (children, 6-7 years; adolescents, 13-14 years; and adults, ≥19 years). Eligible adults were the parents or guardians of children and adolescents included in the surveys. In individuals with asthma diagnosed by a doctor, we collated responses on past-year asthma medicines use (type of inhaled or oral medicine, and frequency of use). Questions on asthma symptoms and health visits were used to define past-year symptom severity and extent of asthma control. Income categories for countries based on gross national income per capita followed the 2020 World Bank classification. Proportions (and 95% CI clustered by centre) were used to describe results. Generalised structural equation multilevel models were used to assess factors associated with receiving medicines and having poorly controlled asthma in each age group.

FINDINGS

Overall, 453 473 individuals from 63 centres in 25 countries were included, comprising 101 777 children (6445 [6·3%] with asthma diagnosed by a doctor), 157 784 adolescents (12 532 [7·9%]), and 193 912 adults (6677 [3·4%]). Use of asthma medicines varied by symptom severity and country income category. The most used medicines in the previous year were inhaled short-acting β2 agonists (SABA; range across age groups, 29·3-85·3% participants) and inhaled corticosteroids (12·6-51·9%). The proportion of individuals with severe asthma symptoms not taking inhaled corticosteroids (inhaled corticosteroids alone or with long-acting β2 agonists) was high in all age groups (934 [44·8%] of 2085 children, 2011 [60·1%] of 3345 adolescents, and 1142 [55·5%] of 2058 adults), and was significantly higher in middle-to-low-income countries. Oral SABA and theophylline were used across age groups and country income categories, contrary to current guidelines. Asthma management plans were used by 4049 (62·8%) children, 6694 (53·4%) adolescents, and 3168 (47·4%) adults; and 2840 (44·1%) children, 6942 (55·4%) adolescents, and 4081 (61·1%) adults had well controlled asthma. Independently of country income and asthma severity, having an asthma management plan was significantly associated with the use of any type of inhaled medicine (adjusted odds ratio [OR] 2·75 [95% CI 2·40-3·15] for children; 2·45 [2·25-2·67] for adolescents; and 2·75 [2·38-3·16] for adults) or any type of oral medicine (1·86 [1·63-2·12] for children; 1·53 [1·40-1·68] for adolescents; and 1·78 [1·55-2·04] for adults). Poor asthma control was associated with low country income (lower-middle-income and low-income countries vs high-income countries, adjusted OR 2·33 [95% CI 1·32-4·14] for children; 3·46 [1·83-6·54] for adolescents; and 4·86 [2·55-9·26] for adults).

INTERPRETATION

Asthma management and control is frequently inadequate, particularly in low-resource settings. Strategies should be implemented to improve adherence to asthma treatment guidelines worldwide, with emphasis on access to affordable and quality-assured essential asthma medicines especially in low-income and middle-income countries.

FUNDING

International Union Against Tuberculosis and Lung Disease, Boehringer Ingelheim New Zealand, AstraZeneca, UK National Institute for Health Research, UK Medical Research Council, European Research Council, the Spanish Instituto de Salud Carlos III.

TRANSLATION

For the Spanish translation of the abstract see Supplementary Materials section.

Outcomes of young children hospitalized with acute wheezing

BACKGROUND

Wheezing in preschool children is a common symptom.

OBJECTIVE

The study aimed to determine an incidence of recurrent wheezing among young children who had been hospitalized with acute wheezing after 12 months. Factors associated with recurrent wheezing were explored.

METHODS

A longitudinal study was conducted among 236 children, aged between 6 months and 5 years, who were hospitalized with acute wheezing in 4 hospitals located in Bangkok and adjacent provinces, Thailand. Demographics, house environments and clinical characteristic data were collected at entry. Serum specific IgE levels against common food and inhalant allergens and serum 25-hydroxyvitamin D (25OHD) concentrations were measured.

RESULTS

At entry, the mean age was 24.4 months (SD = 15.7 months). Of 236 hospitalized children with acute wheezing, ninety-four cases (39.8%) were the first wheezing episode of life. By laboratory results, 197 (83.5%) and 56 (23.7%) children were atopic and had vitamin D insufficiency respectively. There were 195 cases completely followed for 12 months. One-year risk of emergency visits and hospitalization due to recurrent wheezing were 49.7% and 23.1% respectively. By multivariable analysis, being the second born child or more, vitamin D insufficiency, "ever wheeze", and allergic rhinitis were significantly associated with recurrent wheezing within 12 months with adjusted odds ratios of 2.5 (95% confidence interval: 1.3-5.3), 2.3 (95% confidence interval: 1.1-4.4), 1.9 (95% confidence interval: 1.2-3.5), and 1.6 (95% confidence interval: 1.3-2.9) respectively.

CONCLUSIONS

Being the second born child or more, vitamin D insufficiency, ever wheeze, and allergic rhinitis were significant risks of recurrent wheezing.

Prevalence and severity of asthma, rhinoconjunctivitis and eczema in children from the Bangkok area: The Global Asthma Network (GAN) Phase I

BACKGROUND

As noted in the reports of ISAAC phase I and III, allergic diseases are very common in Thailand, especially among younger children.

OBJECTIVE

The objectives of this project are to study the prevalence and severity of the most common allergic diseases. i.e. asthma, rhinoconjunctivitis and eczema among children living in Bangkok.

METHODS

A cross-sectional multi-centers survey using GAN Core questionnaires on asthma, rhinoconjunctivitis and eczema symptoms were completed by parents of children aged 6-7 years and children aged 13-14 years.

RESULTS

The total of 6,291 questionnaires were eligible for the analysis. The cumulative vs. 12-month period prevalence of the three conditions for all children were: 24.4% vs. 13.5% for wheezing, 51.1% vs. 43.6% for rhinitis and 15.8% vs. 14.2% for eczema, respectively. The period prevalence of wheezing for younger children (14.6%) was higher than for older children (12.5%). Prevalences of severe wheeze and exercise wheeze were more common among older children (2.9% and 14.8%). The 12-month prevalences of rhinitis (43.6%) and rhinoconjunctivitis (16.3%) were higher in both age groups. Eczema, as the same to the other conditions, occurred more frequently in both groups (period prevalence of 14.3% and 14.0%) comparing to ISAAC phase III.

CONCLUSION

Allergic conditions are very common diseases among children residing in Bangkok. There is an urgent need for an in-depth study to define epidemiological factors responsible for this increase.

Prevalence and risk factors of allergic rhinitis in children in Bangkok area

BACKGROUND

Allergic rhinitis (AR) is a disease with a high global disease burden and significant morbidity and expense. Risk factors are not well understood.

OBJECTIVE

The objective of our project is to study the prevalence and risk factors of AR in children living in the Bangkok area.

METHODS

A cross-sectional, multi-center survey using new GAN core questionnaires on current AR and risk factors was completed by 3,074 parents of children aged 6-7 years and by 3,217 children aged 13-14 years, directly.

RESULTS

The prevalence of current AR in children aged 6-7 years and 13-14 years was 15.0% (95% confidence interval [CI]:13.8-16.3%) and 17.5% (95% CI: 16.2-18.8%), respectively. The prevalence of severe AR in children aged 6-7 years and 13-14 years was 1.0% (95% CI: 0.6-1.3%) and 1.9% (95% CI: 1.4-2.4%), respectively. Co-morbidity with asthma and eczema was 27.1% and 24.6%, respectively. Significant factors associated with AR include parental history of asthma (p = 0.025), parental history of AR (p < 0.001), parental history of eczema (p < 0.001), lower respiratory tract infection in the first year of life (p < 0.001), breastfeeding (p = 0.019), current use of paracetamol (p < 0.001), exercise (p < 0.001), current cat exposure (p = 0.008), and truck traffic on the street of residence (< 0.001).

CONCLUSION

AR is a common disease among children residing in Bangkok. This study confirms that a family history of atopy (asthma, AR, and eczema), antibiotics given in the first year of life, current paracetamol use, exercise, current cat exposure, and truck traffic on the street of residence are important and significant risk factors for AR symptoms.

The natural history of atopic dermatitis and its association with Atopic March

BACKGROUND

Atopic dermatitis (AD) is the first manifestation of Atopic March. The natural history of AD and predictive factors for Atopic March have not been widely studied in Asia.

OBJECTIVE

To study the natural history and associated factors of disease remission and risk of respiratory allergy in Thai children with AD.

METHODS

Medical records of AD patients attending Allergy clinic at Siriraj hospital from 2004-2014 were reviewed. Patients were further followed-up to obtain current symptoms and treatment.

RESULTS

One hundred and two AD patients (60.8% female) were followed for 10.2±4.7 years. The median age at diagnosis was 1.5 (0.1-12.0) years. The most common allergen sensitization was Dermatophagoides pteronyssinus and Dermatophagoides farinae. Forty-four percent of patients had complete remission at the median age of 6.3 (2.0-15.0) years. Forty-seven percent of early AD patients (onset < 2 years) had concomitant food allergy which egg and cow's milk were leading causes. The remission rate of AD was higher in early AD than later onset AD (p=0.02). Allergic rhinitis (AR) and asthma were diagnosed in 61.8% and 29.4% of the patients at the median age of 4.6 and 3.8 years, respectively. Early AD and food allergies were significantly associated with early asthma (onset < 3years) (OR=10.80, p< 0.01 and OR=8.70, p=0.01).

CONCLUSION

Almost half of AD children had complete remission at school age with a better prognosis in early AD. At preschool age, two-thirds and one-third developed AR and asthma, respectively. Early AD and food allergy were risk factors of early asthma.

Economic Burden of Hospitalization with Acute Wheezing in Preschool Children: A Multi-Center Study

BACKGROUND

Wheezing is an important health problem in Thailand especially among preschool age.

OBJECTIVE

The aim of this study was to estimate costs of wheezing for hospitalization in preschool children under patient, provider, and societal perspectives.

MATERIAL AND METHOD

Two hundred and thirty-four participants who were admitted with acute wheezing at 4 hospitals including Thammasat University Hospital, Saraburi Hospital, Bhumibol Adulyadej Hospital and King Chulalongkorn Memorial Hospital during July 2014 to June 2015 were included in the present study. Data from hospital financial database and caregivers’ expenses were collected. Cost-to-charge ratio method was employed for valuation of direct medical costs. Informal care costs were determined by human capital approach.

RESULTS

The means of patient, provider and societal costs per admission were 3,020 THB (SD = 6,632 THB), 18,126 THB (SD = 16,898 THB), and 20,269 THB (SD = 20,537 THB) respectively. The main cost component in provider and societal perspective were accommodation costs during admission. Informal care cost was a major cost component for direct nonmedical costs. The economic burden of acute wheezing admission of preschool children in Thailand was estimated as 759 million THB per year.

CONCLUSION

These costs of illness analysis provided an evidence of economic burden and costs of preschool wheezing in hospitalization in Thailand.

Pest and allergen exposure and abatement in inner-city asthma: a work group report of the American Academy of Allergy, Asthma & Immunology Indoor Allergy/Air Pollution Committee

Our work group report details the importance of pest allergen exposure in inner-city asthma. We will focus specifically on mouse and cockroach exposure. We will discuss how exposure to these pests is common in the inner city and what conditions exist in urban areas that might lead to increased exposure. We will discuss how exposure is associated with allergen sensitization and asthma morbidity. Finally, we will discuss different methods of intervention and the effectiveness of these tactics.

Specific allergy to Penaeus monodon (seawater shrimp) or Macrobrachium rosenbergii (freshwater shrimp) in shrimp-allergic children

BACKGROUND

Allergy to specific shrimp species has not been studied systematically by oral challenges. A comparison of allergy to different shrimp species, especially seawater or freshwater varieties treatment, would be useful in testing shrimp-allergic subjects.

OBJECTIVE

The aim of the study was to identify cases of specific allergy to seawater shrimp, Penaeus monodon (Pm), or freshwater shrimp, Macrobrachium rosenbergii (Mr), among shrimp-allergic children. Comparisons of skin tests using commercial and crude shrimp extracts plus the prick-to-prick (PTP) method were investigated.

METHODS

Sixty-eight children with a history of shrimp allergy and skin tests positive to shrimp were orally challenged to both shrimp species. Reactivity to skin prick tests using extracts of Pm (PmSPT), Mr (MrSPT), commercial shrimp (ComSPT), and PTP tests (PmPTP, MrPTP) was compared.

RESULTS

Food challenges identified specific allergy to Pm and Mr in 17.65% and 23.53% of the subjects, respectively. Positive and negative challenges to both shrimp species were found in 47.06% and 11.76% of the subjects, respectively. Correlations between the mean weal diameter (MWD) from ComSPT-PmSPT, ComSPT-PmPTP, ComSPT-MrPTP, PmSPT-PmPTP and MrSPT-MrPTP, but not ComSPT-MrSPT, were observed. The MWD from PmSPT and PmPTP were significantly larger in patients with positive than negative challenges to P. monodon (P<0.05). There was a trend that MWD from MrSPT were larger in patients with positive than negative challenges to M. rosenbergii (P=0.058). In the Pm allergy group, PmSPT with an MWD of 30 mm provided 80% predictive probability for positive challenges. PmPTP and ComSPT with an MWD of 22.5 and 20 mm provided 95% predictive probability, respectively. In the Mr allergy group, MrSPT with an MWD of 30 mm provided 95% predictive probability.

CONCLUSION

Specific allergy to Pm or Mr was confirmed by food challenges. SPT using crude extracts and the PTP test are useful tools for screening shrimp sensitization before a food challenge. The predictive probability of SPT is helpful where a food challenge is not feasible.

Anaphylaxis in an emergency department: a 2-year study in a tertiary-care hospital

The aim of this study was to estimate the incidence of anaphylaxis in the emergency department of a tertiary-care hospital, describe the clinical features and the management of the patients and determine those with mild manifestations. A retrospective study was conducted from 2005 to 2006 using anaphylaxis-related ICD-10 terms. Two different sets of criteria for the diagnosis of anaphylaxis were applied, first the criteria previously accepted by emergency practice, followed by the recent criteria set forth at the 2005 international meeting. Sixty-four patients fulfilled the previous criteria with an average incidence of 52.5 per 100,000 patients per year with a shift towards females in 2006. The most common presentations were cutaneous, followed by respiratory symptoms. Food allergy was the most common cause, especially prawn. After applying the recent criteria, 13 patients (20.4%) were excluded, which reduced the incidence to 42.2 per 100,000 patients per year. Long term follow up is suggested for the possible or mild cases that were re-categorized.

Chronic rhinosinusitis and recurrent nasal polyps in two children with IgG subclass deficiency and review of the literature

Chronic rhinosinusitis (CRS) is a chronic inflammatory disorder of mucosa of the nose and the paranasal sinuses. Two major forms of CRS can be differentiated; CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). The pathophysiology and etiology of nasal polyps (NPs) are partly understood. IgG subclass deficiency was shown to be associated with an increased susceptibility to infections. However the association between NPs and IgG subclass deficiency has never been reported.

OBJECTIVES

To report two cases of recalcitrant CRS and recurrent NPs with IgG subclass deficiency.

CASE REPORT

Two children (6 and 8 year-old boys) were referred to the Pediatric Allergy/Immunology Clinic, Siriraj Hospital due to a prolonged history of CRS and recurrent NPs. Both of them were treated with aggressive medical (topical and systemic corticosteroids, antibiotics, leukotriene antagonist, nasal irrigation) as well as surgical therapy, without significant improvement. Immunologic investigation in both patients showed that IgG, IgA, and IgM level were normal. IgG subclasses level in patient No. 1 were IgG1 1,235 (280-1120) mg/dl (79%), IgG2 235 (30-630) mg/dl (23.5%), IgG3 27.3 (40-250) mg/dl (1.74%), and IgG4 92.4 (11-620) mg/dl (5.9%). IgG subclasses level in patient No. 2 were IgG1 1,139 (280-1120) mg/dl (82.5%), IgG2 170 (30-630) mg/dl (12.3%), IgG3 5.6 (40-250) mg/dl (0.4%), IgG4 65.7 (11-620) mg/dl (4.8%). The diagnosis of CRS and recurrent NPs with IgG3 subclass deficiency in the first patient and IgG2/IgG3 subclass deficiency in the second patient were made. Patient No. 1 was given monthly IVIG therapy for the total of 7 courses and medications were gradually tapered. Currently, the patient is doing well after the cessation of IVIG therapy for 3 months. Patient No. 2 denied the IVIG treatment and was lost to follow up.

CONCLUSION

We reported two cases of recalcitrant CRS and recurrent NPs in children. Immunologic work up revealed IgG subclass deficiency. The treatment with monthly IVIG improved CRS and NPs in treated patient which brought up the possibility of association between NPs and IgG subclass deficiency. Further study on the direct role of IVIG in NPs will be needed in the future.

Seroprevalence of Epstein-Barr virus antibody among children in various age groups in Bangkok, Thailand

There are no current data on previous Epstein-Barr virus (EBV) infections in different age groups of Thai children. This study was conducted to determine the prevalence of anti-EBV IgG antibody in healthy children of various age ranges in Bangkok, Thailand. Between June and December 1998, blood samples were collected from 425 volunteers aged 6 months to 15 years who attended a well baby clinic in the northern suburban part of Bangkok, Thailand. Serum samples were assayed for specific anti-EBV IgG antibodies using a commercial enzyme-linked immunosorbent assay kit. The percentage of children with positive anti-EBV IgG antibody increased with advancing age. The overall seropositivity rate was 72.7%. Children with anti-EBV IgG antibody were significantly older than those without the antibody. Seronegative children were reared at home significantly more frequently than seropositive children. These seroopidemiologic data will guide calculation of the appropriate age for administration of an EBV vaccine to children, when it becomes available.