Changing prevalence and severity of childhood allergic diseases in kyoto, Japan, from 1996 to 2006

Characterizing Fit-for-Purpose Real-World Data: An Assessment of a Mother-Infant Linkage in the Japan Medical Data Center Claims Database

Purpose

Observational postapproval safety studies are needed to inform medication safety during pregnancy. Real-world databases can be valuable for supporting such research, but fitness for regulatory purpose must first be vetted. Here, we demonstrate a fit-for-purpose assessment of the Japan Medical Data Center (JMDC) claims database for pregnancy safety regulatory decision-making.

Patients and Methods

The Duke-Margolis framework considers a database's fitness for regulatory purpose based on relevancy (capacity to answer the research question based on variable availability and a sufficiently sized, representative population) and quality (ability to validly answer the research question based on data completeness and accuracy). To assess these considerations, we examined descriptive characteristics of infants and pregnancies among females ages 12-55 years in the JMDC between January 2005 and March 2022.

Results

For relevancy, we determined that critical data fields (maternal medications, infant major congenital malformations, covariates) are available. Family identification codes permitted linkage of 385,295 total mother-infant pairs, 57% of which were continuously enrolled during pregnancy. The prevalence of specific congenital malformation subcategories and maternal medical conditions were representative of the general population, but preterm births were below expectations (3.6% versus 5.6%) in this population. For quality, our methods are expected to accurately identify the complete set of mothers and infants with a shared health insurance plan. However, validity of gestational age information was limited given the high proportion (60%) of missing live birth delivery codes coupled with suppression of infant birth dates and inaccessibility of disease codes with gestational week information.

Conclusion

The JMDC may be well suited for descriptive studies of pregnant people in Japan (eg, comorbidities, medication usage). More work is needed to identify a method to assign pregnancy onset and delivery dates so that in utero medication exposure windows can be defined more precisely as needed for many regulatory postapproval pregnancy safety studies.

TFOS Lifestyle Report: Impact of environmental conditions on the ocular surface

Environmental risk factors that have an impact on the ocular surface were reviewed and associations with age and sex, race/ethnicity, geographical area, seasonality, prevalence and possible interactions between risk factors are reviewed. Environmental factors can be (a) climate-related: temperature, humidity, wind speed, altitude, dew point, ultraviolet light, and allergen or (b) outdoor and indoor pollution: gases, particulate matter, and other sources of airborne pollutants. Temperature affects ocular surface homeostasis directly and indirectly, precipitating ocular surface diseases and/or symptoms, including trachoma. Humidity is negatively associated with dry eye disease. There is little data on wind speed and dewpoint. High altitude and ultraviolet light exposure are associated with pterygium, ocular surface degenerations and neoplastic disease. Pollution is associated with dry eye disease and conjunctivitis. Primary Sjögren syndrome is associated with exposure to chemical solvents. Living within a potential zone of active volcanic eruption is associated with eye irritation. Indoor pollution, "sick" building or house can also be associated with eye irritation. Most ocular surface conditions are multifactorial, and several environmental factors may contribute to specific diseases. A systematic review was conducted to answer the following research question: "What are the associations between outdoor environment pollution and signs or symptoms of dry eye disease in humans?" Dry eye disease is associated with air pollution (from NO2) and soil pollution (from chromium), but not from air pollution from CO or PM10. Future research should adequately account for confounders, follow up over time, and report results separately for ocular surface findings, including signs and symptoms.

A School Eye Health Rapid Assessment (SEHRA) planning tool: Module to survey the magnitude and nature of local needs

BACKGROUND

Eye conditions in children can have negative consequences on visual functioning and quality of life. There is a lack of data on the magnitude of children with eye conditions who need services for effective planning of school eye health programmes. To address this, the School Eye Health Rapid Assessment (SEHRA) tool is being developed to collect data to support school eye health programme planning.

METHODS

The module, 'the magnitude and nature of local needs in school children' is the first of six modules in the SEHRA tool. The module outlines a school-based cluster survey designed to determine the magnitude of eye health needs in children. This paper outlines the survey sampling strategy, and sample size calculations.

RESULTS

The requirements for the SEHRA survey indicate that in regions where a larger sample size is required, or where fewer schools are recruited to the survey, confidence in the accuracy of the data will be lower.

CONCLUSIONS

The SEHRA survey module 'the magnitude and nature of local needs in school children' can be applied in any context. In certain circumstances, the confidence in the survey data will be reduced.

Lirentelimab for severe and chronic forms of allergic conjunctivitis

BACKGROUND

Allergic conjunctivitis (AC) is an ocular inflammatory disease with symptoms driven by eosinophils and mast cells. Allergic comorbidities are common. Current treatments are often ineffective in severe AC and limited by potential side effects. Lirentelimab is an anti-sialic acid-binding immunoglobulin-like lectin-8 mAb that depletes eosinophils and inhibits mast cells.

OBJECTIVE

We sought to determine safety and preliminary efficacy of lirentelimab in an open-label, phase 1b study.

METHODS

Patients with chronic, severely symptomatic atopic keratoconjunctivitis, vernal keratoconjunctivitis, and perennial AC, and who had history of topical or systemic corticosteroid use, were enrolled to receive up to 6 monthly lirentelimab infusions (dose 1: 0.3 mg/kg, dose 2: 1 mg/kg, subsequent doses: 1 or 3 mg/kg). Changes from baseline in peripheral blood eosinophils, changes in patient-reported symptoms (measured by daily Allergic Conjunctivitis Symptom Questionnaire, including atopic comorbidities), changes in investigator-reported ocular signs and symptoms (Ocular Symptom Scores), changes in quality of life, and changes in tear cytokine and chemokine levels were assessed.

RESULTS

Thirty patients were enrolled (atopic keratoconjunctivitis n = 13, vernal keratoconjunctivitis n = 1, perennial AC n = 16), 87% of whom had atopic comorbidities. After lirentelimab treatment, mean improvement was observed in Allergic Conjunctivitis Symptom Questionnaire score (-61%; 95% CI, -75% to -48%) and Ocular Symptom Scores (-53%; 95% CI, -76% to -31%), consistent across atopic keratoconjunctivitis, vernal keratoconjunctivitis, and perennial AC groups. There was substantial improvement in atopic comorbidities, with -55% (95% CI, -78% to -31%), -50% (95% CI, -82% to -19%), and -63% (95% CI, -87% and -38%) reduction in symptoms of atopic dermatitis, asthma, and rhinitis, respectively. Levels of key mediators of inflammation were reduced in patient tears after lirentelimab treatment. The most common adverse effects were mild to moderate infusion-related reactions.

CONCLUSIONS

Lirentelimab was well tolerated, improved severe AC and concomitant atopic symptoms, and reduced inflammatory mediators in patient tears.

English Version of Clinical Practice Guidelines for the Management of Atopic Dermatitis 2021

This is the English version of the Clinical Practice Guidelines for the Management of Atopic Dermatitis 2021. Atopic dermatitis (AD) is a disease characterized by relapsing eczema with pruritus as a primary lesion. In Japan, from the perspective of evidence-based medicine, the current strategies for the treatment of AD consist of three primary measures: (i) use of topical corticosteroids, tacrolimus ointment, and delgocitinib ointment as the main treatment of the inflammation; (ii) topical application of emollients to treat the cutaneous barrier dysfunction; and (iii) avoidance of apparent exacerbating factors, psychological counseling, and advice about daily life. In the present revised guidelines, descriptions of three new drugs, namely, dupilumab, delgocitinib, and baricitinib, have been added. The guidelines present recommendations to review clinical research articles, evaluate the balance between the advantages and disadvantages of medical activities, and optimize medical activity-related patient outcomes with respect to several important points requiring decision-making in clinical practice.

A time-series analysis on generalized additive model for atmospheric pollen concentration and the number of visits of allergic conjunctivitis, Beijing, China

The objective of this study is to investigate the correlation between atmospheric pollen concentration and daily visits for allergic conjunctivitis. Daily counts of outpatient visits for allergic conjunctivitis, atmospheric pollen concentration, and meteorological data during pollen season of 2018 and 2019 were collected from Beijing Shijitan Hospital, China. A time-series analysis on generalized additive model with Poisson distribution was used to estimate the relationship between pollen concentration and visits for allergic conjunctivitis, after controlling for the time trend, weather variables, day of the week, and holiday effect. The RStudio was used to generate Spearman correlation coefficients and then to plot the lag-response curves for specific and incremental cumulative effects of relative risk (RR). There was a moderate positive correlation between pollen concentration and visits for allergic conjunctivitis, and Spearman's correlation coefficient was 0.521 in 2018 and 0.515 in 2019 (P<0.01). The specific cumulative effect peak associated with per 10 grains/kmm² increases of atmospheric pollen concentration was within 0 day, and the lag time was 8 days(2018, 2019). The incremental cumulative effect peak associated with per 10 grains/kmm² increases of atmospheric pollen concentration occurred on lag day 10 (2018) and lag day 8 (2019), and the lag time was 14 days (2018) and 20 days (2019). Elevated concentrations of pollen increase the risk of allergic conjunctivitis with a time lag effect.

Altered retinal nerve fiber layer thickness in children with allergic conjunctivitis: the Nanjing eye study

Background

So far, few data are available on the relationship between allergic conjunctivitis (AC) and ocular fundus. Whether retinal parameters change in patients with AC remains unknown. In this study, we investigated the influence of AC on retinal thickness and vessel density among 7-years-old school-age children.

Methods

This large population-based study is part of the Nanjing Eye Study (NES). Comprehensive examinations including anthropometric parameters, refraction, ocular biometric parameters, intraocular pressure and retinal parameters were conducted on each child. Retinal thickness and vessel density were assessed using the optical coherence tomography angiography. Information on AC was obtained from a comprehensive questionnaire.

Results

A total of 739 children (mean age ± SD: 7.40 ± 0.29 years) had complete eye examination and questionnaire data we needed. Ninety-four children (12.7%) had AC, among which, 5 children had the history of corticosteroid use and were excluded from the final analysis. Spherical equivalent, axial length, body mass index and birth weight were correlated with retinal parameters. After adjusting for sex, age, spherical equivalent, axial length, body mass index, birth weight and premature history, children with AC had thinner retinal nerve fiber layer thickness for average (117.39 versus 120.97 μm, p = 0.007), temporal (80.73 versus 84.34 μm, p = 0.001), nasal (98.82 versus 102.18 μm, p = 0.049) and inferior (152.68 versus 157.06 μm, p = 0.034) quadrants than the control group.

Conclusions

Children with AC tended to have thinner retinal nerve fiber layer thickness. More attention is needed to fundus condition of children with AC.

Supplementary information

The online version contains supplementary material available at 10.1186/s12886-022-02399-7.

High Incidence of Atopic Dermatitis among Children Whose Fathers Work in Primary Industry: The Japan Environment and Children's Study (JECS)

The hygiene hypothesis assumes a low incidence of allergic diseases in families engaging in farming work. However, a few studies have indicated rural life as a potential risk factor for atopic dermatitis (AD). Using a large Japanese birth cohort dataset, we calculated the accumulated incidence of AD in children aged 6 months and 1, 2, and 3 years by family business and the hazard ratio. We adjusted for confounding factors. The father's job was considered the family business. We analysed data on 41,469 father-child pairs at 6 months of age, 40,067 pairs at 1 year, 38,286 pairs at 2 years, and 36,570 pairs at 3 years. We found the highest accumulated incidence of AD among children with fathers engaged in primary industry, with 2.5% at the age of 6 months, 6.6% at 1 year, 12.0% at 2 years, and 15.4% at 3 years. Among primary industry occupations, forestry was associated with the highest incidence of AD across these ages. The hazard ratio of AD was also highest for children whose family business was primary industry. In conclusion, the highest incidence and hazard ratio of AD were observed among children whose fathers worked in primary industry.

Increased Risk of Postpartum Depression in Women With Allergic Rhinitis During Pregnancy: A Population-Based Case-Control Study

OBJECTIVES

Allergic rhinitis (AR) is associated with increased risk of major depression in the general population, however, no previous study has evaluated its role among pregnant women. We aimed to investigate the potential impact of AR during pregnancy on the development of postpartum depression (PPD).

METHODS

This is a population-based case-control study. Data were retrieved from the National Health Insurance Research Database (NHIRD). Medical records of a total of 199 470 deliveries during 2000 and 2010 were identified. Among which, 1416 women with PPD within 12 months after delivery were classified as the case group, while 198 054 women without PPD after delivery formed the control group. Univariate and multivariate regression analyses were conducted to determine the associations between AR during pregnancies and other study variables with PPD.

RESULTS

AR during pregnancy was found in 9.53% women who developed PPD and 5.44% in women without PPD. After adjusting for age at delivery, income level, various pregnancy and delivery-related conditions, asthma, atopic dermatitis and other medical comorbidities in the multivariate analysis, AR was significantly associated with increased odds of PPD (aOR: 1.498, 95% CI: 1.222-1.836).

CONCLUSION

AR during pregnancy was independently and significantly associated with an approximately 50% increased risk of PPD among women giving birth. Closely monitoring of AR is warranted in the future in order to optimize mother and child outcomes after delivery.

Air pollution and meteorological conditions significantly contribute to the worsening of allergic conjunctivitis: a regional 20-city, 5-year study in Northeast China

This study is the first to explore the potential associations among allergic conjunctivitis (AC), air pollution, and meteorological conditions in Northeast China. Data of meteorology, ambient atmospheric pollutants, and the incidence of allergic conjunctivitis (IAC) in prefecture-level cities between the years 2014 and 2018 are analyzed. The results show an increasing trend in the AC of average growth rate per annum 7.6%, with the highest incidence in the provincial capitals. The IAC is positively correlated with atmospheric pollutants (i.e., PM_2.5, PM₁₀, CO, SO₂, NO₂, and O₃) and meteorological factors (i.e., air temperature and wind speed), but negatively correlated with relative humidity. These results suggest that the IAC is directly proportional to pollution level and climatic conditions, and also the precedence of air pollution. We have further obtained the threshold values of atmospheric pollutants concentration and meteorological factors, a turning point above which more AC may be induced. Compared with the air quality standard advised by China and the World Health Organization (WHO), both thresholds of PM₁₀ (70 μg m^-3) and PM_2.5 (45 μg m^-3) are higher than current standards and pose a less environmental risk for the IAC. SO₂ threshold (23 μg m^-3) is comparable to the WHO standard and significantly lower than that of China's, indicating greater environmental risks in China. Both thresholds of NO₂ (27 μg m^-3) and O₃ (88 μg m^-3) are below current standards, indicating that they are major environmental risk factors for the IAC. Our findings highlight the importance of atmospheric environmental protection and reference for health-based amendment.

The Prevalence of Asthma among Iranian Children and Adolescent: A Systematic Review and Meta-Analysis

BACKGROUND

Asthma is an important reason for hospitalization in children aged under five years. Information about the current status of asthma in Iranian children can help the Iranian health sector plan carefully and prevent asthma incidence by educating the families. The present systematic review and meta-analysis is aimed at estimating asthma prevalence in Iranian children and adolescents.

METHOD

Data were found using keywords such as prevalence, epidemiology, asthma, adolescent, children, pediatrics, Iran in Web of Science, Scopus, PubMed, Cochrane, and Embase databases. Three national databases, including Magiran, Barakat Pharmed Co (Iran medex), and Scientific Information Databank (SID) were searched until 1 October 2020. Cross-sectional and original studies were included in the study, and then, quality assessment was done using the National Institutes of Health's Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. A pooled estimated prevalence of asthma was calculated using Der Simonian-Laird random model. Egger's test was used to evaluate publication bias. The data were analyzed using the STATA software version 16.

RESULTS

30 studies were selected and investigated. The prevalence of asthma in children and adolescents was 6% and 8%, and the prevalence in boys and girls was 9% and 8%, respectively. Among the asthma symptoms, wheezing had the most prevalence (17% in children and 19% in adolescents) and sleep disturbance had the lowest prevalence (6% in children and 6% in adolescents).

CONCLUSION

The prevalence of asthma in Iranian children and adolescents is lower than in the world. Existing strategies should be pursued followed. Also, guidelines for asthma control and prevention should be considered in the future.

Determinants of the utilization of allergy management measures among hay fever sufferers: a theory-based cross-sectional study

Background

The quality of life of chronically ill individuals, such as hay fever sufferers, is significantly dependent on their health behavior. This survey aimed to explain the health-related behavior of allergic individuals using the protection motivation theory (PMT) and the transtheoretical model (TTM).

Methods

The influencing variables stated by PMT were operationalized based on data from semistructured pilot interviews and a pretest with 12 individuals from the target population. The final questionnaire inquired perceived seriousness and severity of hay fever, response efficacy, response costs, self-efficacy, and the use of various hay fever management measures in relation to the TTM stages. Multivariate logistic regression was performed to investigate the relationships between the PMT constructs and the examined health behavior.

Results

A total of 569 allergic individuals completed the online questionnaire. Only 33.26% of allergic individuals were in the maintenance stage for treatment under medical supervision, and almost 60% preferred hay fever self-management. A total of 67.56% had a well-established habit of taking anti-allergic medication, but only 25.31% had undergone specific immunotherapy. The likelihood of seeking medical supervision was positively influenced by perceived severity (OR = 1.35, 95% CI: 1.02–1.81), perceived seriousness (OR = 2.12, 95% CI: 1.56–2.89), and self-efficacy (OR = 4.52, 95% CI: 3.11–6.65). The perceived severity of symptoms predicted the practice of hay fever self-management (OR = 1.60, 95% CI: 1.21–2.11), as well as anti-allergic medication intake (OR = 1.65, 95% CI: 1.16–2.35). The latter measure was also positively influenced by self-efficacy (OR = 1.52, 95% CI: 1.01–2.28) and hay fever self-management (OR = 4.76, 95% CI: 2.67–7.49). Undergoing specific immunotherapy was significantly predicted only by medical supervision (OR = 9.80, 95% CI: 8.16–13.80). Allergen avoidance was a strategy used by allergic individuals who preferred hay fever self-management (OR = 2.56, 95% CI: 1.87–3.52) and experienced notable symptom severity (OR = 2.12, 95% CI: 1.60–2.81).

Conclusion

Educational interventions that increase the awareness of health risks associated with inadequate hay fever management and measures to increase self-efficacy might be beneficial for the promotion of appropriate hay fever management among allergic individuals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-09959-w.

Epidemiological aspects of allergic conjunctivitis

The prevalence of ocular allergies has been increasing worldwide for the past several decades. The geographical distribution and hot spots of rhinoconjunctivitis have been documented in a global survey by the International Study of Asthma and Allergies in Childhood (ISAAC). ISAAC indicated that Africa, Latin America, and Japan were notable for their high prevalence of rhinoconjunctivitis. The outcomes of follow-up studies of regional differences and the characteristics of allergic conjunctivitis are summarized in this review. Currently, comorbid diseases and socioeconomic and environmental factors, including climate and air pollution, are proposed to contribute to the regional differences in the prevalence of allergic conjunctivitis. Of them, rhinitis has been shown repeatedly to be significantly associated with allergic conjunctivitis. Their mechanistic aspects on association with the prevalence of systemic allergic diseases have been reviewed by examining the birth cohort or in vitro analyses. A vision threatening form of ocular allergy, vernal keratoconjunctivitis, is prevalent in the African countries and Japan. Of the proposed associated factors, air pollution was shown to contribute not only to aggravating the symptoms but also to the increase in the incidence of its severe forms. Its mechanistic aspects are discussed in this review in the context of comorbid diseases.

Evaluation of a possible association between allergic rhinitis and depression, suicidal ideation, and suicide attempts among adolescents based on a nationwide cross-sectional study

OBJECTIVE

We assessed associated factors for depression and suicidality among adolescents with allergic rhinitis (AR) by analyzing data from annual Korea Youth Risk Behavior Web-based Surveys (KYRBSs) completed from 2007 to 2017.

METHODS

Data from the KYRBS were obtained from a stratified, multistage, clustered sample. Using self-reported questionnaires, students provided yes-or-no answers to questions addressing their doctor-diagnosed AR and self-experienced depression, suicidal ideation and suicide attempts. Associated factors for depression and suicidality were identified by logistic regression models after controlling for potential confounding factors. A total of 818,684 adolescents were targeted, and 788,411 adolescents completed the survey.

RESULTS

An AR diagnosis was reported in 30.8% of respondents. Among respondents with AR, 34.5%, 18.4%, and 4.2% reported depression, suicidal ideation, and suicide attempts, respectively. Adolescents with AR were significantly more likely to have negative mental health status, including suicidality than adolescents without AR. After multiple logistic regression analyses, perception of stress was most strongly associated with depression and suicidal ideation (adjusted odds ratio: 5.16 [95% confidence interval; 5.04-5.28], 4.81 [4.65-4.98], respectively). For suicide attempts, subjective unhappiness was most strongly associated (3.63 [3.47-3.79]) among adolescents with AR. Presence of AR itself was also associated with depression and suicidality (1.10 [1.08-1.11], 1.08 [1.06-1.10], 1.05 [1.01-1.08], respectively).

CONCLUSION

Adolescents with AR had significantly greater prevalence of depression and suicidality. Multidisciplinary team approaches, including psychological support, may be needed to prevent suicide among adolescents with AR, especially those with identifiable risk factors.

Clinical practice guidelines for the management of atopic dermatitis 2018

Atopic dermatitis (AD) is a disease characterized by relapsing eczema with pruritus as a primary lesion. The current strategies to treat AD in Japan from the perspective of evidence-based medicine consist of three primary measures: (i) the use of topical corticosteroids and tacrolimus ointment as the main treatment for the inflammation; (ii) topical application of emollients to treat the cutaneous barrier dysfunction; and (iii) avoidance of apparent exacerbating factors, psychological counseling and advice about daily life. The guidelines present recommendations to review clinical research articles, evaluate the balance between the advantages and disadvantages of medical activities, and optimize medical activity-related patient outcomes with respect to several important points requiring decision-making in clinical practice.

Mini-monoka stenting for patients with perennial allergic conjunctivitis

Purpose: To assess the effectiveness of mini-monoka (MM) stenting in treating patients with perennial allergic conjunctivitis (PAC) and punctal stenosis. Methods: A retrospective case analysis was performed on 20 patients (40 eyes) who suffered from PAC with punctal stenosis who underwent MM (FCI Ophthalmics, Pembroke, MA, USA) stenting. Results: Nineteen patients (95%) were females, with an age range of 19-66 years (average 40.6 ± 25.4 years). All 20 patients (100% of eyes) had signs of PAC and punctal stenosis. All 20 patients (40 eyes) had received previous topical treatment including steroids. Nineteen patients (95% of eyes) had significant improvement in their allergy symptoms (tearing and conjunctival inflammation) following MM stenting. Conclusions: Stenosis of the punctum may play a role in the relapsing symptoms in PAC. MM stenting is a simple, safe, effective, and relatively non-invasive treatment option for the management of PAC in the presence of punctal stenosis.

Prevalence of asthma among Middle Eastern children: A systematic review

Background: The prevalence of asthma and allergy has increased during the last decades, especially in children. However, little is known about it in the Middle East region. This systematic review is aimed to estimate the prevalence of asthma among the Middle Eastern children.

Methods: Local and international scientific databases including SID, Iranmedex, Medline and Science Direct were systematically searched for relevant keywords including; asthma, prevalence, children, International Study of Asthma and Allergies in Childhood (ISACC) and the names of Middle Eastern countries for the period of 1996-2011. Papers in Persian and English which met the defined criteria were included into the study. Bibliographies of the extracted articles were also searched. After extraction of data, heterogeneity between studies and publication bias were measured using Egger's-test. Effect size was pooled by the random-effect model. Since significant heterogeneity was found between studies, univariate meta-regression analyses were done to assess the association of variables with the overall results.

Results: Fifty studies in the Middle East examined the prevalence of asthma and allergy in children under the age of 18 years according to the ISAAC criteria and were included. A total number of 289,717 children were examined in the included studies and the prevalence varied from 0.7 % in Isfahan to 22.3 % in Bagdad. The total prevalence of diagnosed asthma was calculated 7.53 % (95% Cl: 6.38-8.75). Prevalence of asthma in the 13-14 years age group was 7.57% (95% Cl: 5.78-9.29) and in 6-7 years age group was 7.43% (95% Cl: 5.75-9.10). The prevalence of asthma among girls, based on random effect model, was 6.30% (95% Cl: 4.97-7.61) and among boys, it was 8.91% (95% Cl: 6.80-11.04).

Conclusion: The prevalence of asthma in the Middle East is lower than most developed countries. However, there is not enough longitudinal data to estimate the trend over time. In order to have more accurate estimates and to provide evidence for proper planning, standard epidemiologic studies should be conducted in countries of the region.

Prevalence, severity and risk factors of allergic disorders among people in south India

BACKGROUND

Allergic disorders are not usually life-threatening conditions but they impair the person's ability to function. It thus adversely affects the psychological wellbeing and quality of life. These implications of allergic disorders can be minimized if strategies are planned for its early identification followed by appropriate interventions.

OBJECTIVES

To find out the prevalence and risk factors of allergic disorders.

METHODS

Data was collected by house to house survey among participants aged 18 years and above using a standardized allergy assessment questionnaire.

RESULTS

Mean age of the 400 participants was 42.8±14.7 years. Majority 105(26.2%) were in the age group 36 to 45 years. Majority were females 287(71.7%) and were house wives 217(54.2%). Majority of participants were of upper socio economic class 98(44.7%) out of 219 and majority were from urban areas 326(81.5%). The prevalence of allergy among participants was found to be 115(28.7%). Out of these 115, 37(32.2%) had possibility of allergy, 60(52.2%) had probability of allergy and the rest 18(15.6%) had very high likelihood for allergy. People residing in semi urban areas had increased risk of allergy (p=0.024) than those from urban areas. The prevalence of asthma was 30(7.5%) and skin allergy was 23(5.8%). Most common precipitating factors for allergy were dust exposure 103(25.8%) followed by seasonal changes 71(17.8%). Family history of allergy was associated with allergy among participants (p<0.001). Usage of firewood was associated with symptoms of respiratory allergy among participants (p=0.01).

CONCLUSION

The study revealed some important determinants of allergic disorders which have important implications to frame appropriate prevention and health educational strategies.

Sports activities enhance the prevalence of rhinitis symptoms in schoolchildren

BACKGROUND

To evaluate the association between sports activities and allergic symptoms, especially rhinitis, among schoolchildren.

METHODS

This longitudinal survey of schoolchildren collected data from questionnaires regarding allergic symptoms based on the International Study of Asthma and Allergies in Childhood (ISAAC) program and sports participation that were distributed to the parents of children at all 12 public primary schools in Ohmi-Hachiman City, Shiga Prefecture, Japan. Data were collected annually from 2011 until 2014, when the children reached 10 years of age. Blood samples were obtained in 2014, and the levels of immunoglobulin (Ig)E specific to four inhalant allergens were measured.

RESULTS

Data from 558 children were analyzed. At 10 years of age, prevalence of asthma and eczema did not differ significantly, while rhinitis was significantly higher (p = 0.009) among children who participated in sports. Prevalence of rhinitis increased as the frequency or duration of sports participation increased (p < 0.01). The prevalence of new-onset rhinitis increased significantly among 10-year-olds with increasing duration of participation in sports (p = 0.03). Among those who participated in continuous sports activities, the prevalence of rhinitis was significantly higher with prolonged eczema (p = 0.006). Sports activities did not increase sensitization to inhalant allergens.

CONCLUSION

Sports activities enhance the prevalence of rhinitis in schoolchildren. Prolonged eczema, together with sports participation, further promotes the symptoms. The mechanisms of these novel findings warrant further investigation.

Sensitization pattern of inhalant allergens in children with asthma who are living different altitudes in Turkey

Variability in children's allergic sensitization has been detected not only among different countries but also among cities within the same nation but yet different climatic areas. The aim of this study was to investigate the sensitization pattern of asthmatic children who lived in different altitude areas: the two largest Turkish cities, Istanbul (sea level) and Erzurum (high altitude). Five hundred and twelve asthmatic children (6-15 years old) from Istanbul (western Turkey, at sea level) and 609 from Erzurum (eastern Turkey, at an altitude of 1800 m) were included in the study. All participants underwent skin testing with common inhalant allergens, spirometry, total IgE level, and clinical examination. The positive sensitization ratio to aeroallergens in children with asthma living at sea level was statistically higher than that in children living in the high altitude group [p = 0.001, OR (odds ratio) 4.9 (confidence interval (CI) 3.67-6.459)]. However, pollen sensitization in asthmatic children living in high altitudes was significantly higher than that in children living at sea level [p = 0.00, OR 2.6 (CI 1.79-3.87)]. Children with asthma who live at high altitudes are characterized by higher pollen but lower mite sensitization rates than those living at sea level in Turkey. Different climatic conditions and altitudes may affect aeroallergen sensitization in children with asthma.

Double-blind placebo-controlled study of bepotastine besilate in pediatric patients with perennial allergic rhinitis

BACKGROUND

Although second-generation antihistamines, such as bepotastine besilate, are recommended as a first-line treatment option for adult perennial allergic rhinitis (PAR), few non-sedating second-generation antihistamines are safe for children.

OBJECTIVE

A double-blind, placebo-controlled, comparative study of 473 pediatric PAR patients (7 - 15 years old) to determine the superiority and safety of bepotastine besilate (10 mg twice daily) relative to placebo for improved total and individual nasal symptom scores compared with baseline.

RESEARCH DESIGN AND METHODS

Subjects were randomized to placebo (n = 233) or bepotastine besilate (n = 240, 10 mg orally twice daily for 2 weeks). Interference of daily life by PAR was assessed by measuring change in individual nasal symptom scores from baseline.

RESULTS

Bepotastine besilate was superior to placebo in terms of total nasal symptom scores, with improved overall nasal symptoms of PAR compared with baseline values. Subgroup analyses demonstrated bepotastine besilate was effective irrespective of age, sex or body weight. No clinically significant adverse drug reactions often observed with first-generation antihistamines were reported and no difference in adverse events between groups was observed.

CONCLUSIONS

Bepotastine besilate is effective and safe for pediatric PAR patients aged 7 - 15 years, and has a significant clinical impact on PAR.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01861522 ( https://clinicaltrials.gov/ct2/show/NCT01861522 ).

Relationship between physique and food avoidance in infants: a study conducted in a community setting in Japan

The relationship between food avoidance during infancy and the growth of Japanese infants in a community health setting has not been well evaluated. In order to assess the growth of infants who avoided either of the three major allergen foods in Japan, eggs, milk or wheat, we employed the results of 4 physical checkups recorded in maternity passbooks and administrated a questionnaire on allergic diseases, height and weight at birth to the guardians of 1,132 infants at the age of 3.5 years. Data was obtained from 890 subjects (78.6%) and 662 subjects (58.5%) who met the inclusion criteria were analyzed. The height, weight and body mass index percentile scores of each subject were calculated. Subjects who avoided either of the three foods at 3.5 years had lower weight percentile scores at 1.5 years, lower height and weight percentile scores at 3.5 years, and lower weight growth rates, compared with the subjects who did not avoid any of the three foods at 3.5 years (P=0.02, 0.03, 0.03, 0.01). The results suggested that there was a negative relationship between physique and food avoidance in infants, and that physical and nutritional assessments are important for food avoiders.

Prevalence and Impact of Past History of Food Allergy in Atopic Dermatitis

BACKGROUND

Increases in allergic diseases have been reported from various epidemiological surveys. However, a few reports demonstrate the comorbidity of food allergy (FA) and allergic march. The aim of this study was to assess the prevalence and comorbidity of allergic diseases in Japanese students.

METHODS

First-year students (n = 3,321; 2,209 male and 1,112 female) at Osaka University were asked about allergic diseases using postal interview sheets. Personal and family histories of doctor-diagnosed allergic diseases, clinical courses, and aggravating factors were included in the questionnaires.

RESULTS

The lifetime prevalence of allergic rhinitis (AR), atopic dermatitis (AD), bronchial asthma (BA), and FA was 35.7%, 16.5%, 9.9%, and 7.0%, respectively. Disease-specific family histories existed for AR, AD, and BA. There was a positive correlation between the number of family histories of allergic disease and comorbidity (R = 0.370, P <0.001). Comorbidity with AD significantly lowered the onset age of both BA (P = 0.010) and AR (P <0.001). In addition, the onset age of AD was remarkably lowered by comorbidity with FA (P <0.001). Comorbidity with FA was the highest risk factor for the progression of allergic march. Although most students showed improvement in AD, BA, and AR over time, the peak recurrence period was observed in adolescence.

CONCLUSIONS

These findings indicate that AD associated with FA accelerates the subsequent progression of allergic march. Early appropriate management for genetically high-risk groups is important for the prevention of allergic march.

Epidemiological characterization and risk factors of allergic rhinitis in the general population in Guangzhou City in china

The prevalence of allergic rhinitis (AR) in China has increased with an apparent geographic variation. The current study aims to investigate the AR prevalence/classification, diagnosis/treatment conditions, trigger factors, and risk factors in the general population of Guangzhou, the third biggest city in China. A cross-sectional survey was performed in the citizens in Guangzhou from December 2009 to March 2010 by using a stratified multistage cluster sampling method. All subjects were asked to complete a comprehensive questionnaire via a face to face interview. A total of 9,899 questionnaires were valid. The prevalence rate of AR in the general population of Guangzhou was 6.24%, with a significant higher prevalence in urban area (8.32%) versus rural area (3.43%). Among the AR subjects, most (87%) were diagnosed with intermittent AR and 87% suffered from moderate-severe symptoms. High percentages of the AR patients did not have previously physician-based diagnosis (34%) or specific medical treatment (55%). Morning time, winter season, and cold air were the most common trigger factors of AR. Family history of AR, current living place, living place during babyhood, smoking, home renovation, and pet ownership were the significant risk factors associated with AR prevalence in the population. The study demonstrated comprehensive epidemiological and clinical information about the AR in Guangzhou population. Change of living environment and lifestyles had strong impacts on the prevalence of AR. Public health policies should help the patients benefit from a proper diagnosis/treatment and specifically target the local risk factors, in order to control the AR incidence.

Do endoscopic features suggesting eosinophilic esophagitis represent histological eosinophilia?

BACKGROUND

Esophageal linear furrows, corrugated rings, and/or white exudates are often seen in patients with eosinophilic esophagitis (EoE); however, whether these are specific to EoE remains unclear. Endoscopic surveillance of these features was conducted to determine whether these represent esophageal eosinophilia, which is essential for the diagnosis of EoE.

PATIENTS AND METHODS

Two thousand seven hundred and sixty-three patients were enrolled consecutively. Target biopsy was carried out when the above features were seen. Histological eosinophilia was defined as 24 or more eosinophils per high-power field (HPF). Associations between features and eosinophilia were analyzed statistically.

RESULTS

Two thousand five hundred and forty-five patients completed the study. Linear furrows, corrugated rings and white exudates were seen in 24, 15 and 45 patients, respectively. These findings somewhat overlapped. Among 58 biopsied patients withany of the above features, these features represented eosinophilia in 14% (3/21), 23% (3/13), and 5% (2/43), respectively. None of the 199 patients who received biopsy for other features had eosinophilia. Two of five eosinophilia patients were diagnosed with EoE. Multiple comparisons revealed that eosinophil counts in linear furrows and corrugated rings but not white exudates were significantly greater than those in other features (12, 9, 1, and <1 eosinophils/HPF on average, respectively).

CONCLUSIONS

An endoscopic feature suggesting EoE does not always represent esophageal eosinophilia and is non-specific for EoE, although it reminds endoscopists of the presence of EoE. The diagnostic utility of linear furrows or corrugated rings for esophageal eosinophilia is superior to that of white exudates.

Clinical correlations of dry eye syndrome and allergic conjunctivitis in Korean children

PURPOSE

Clinical patterns in pediatric patients with dry eye syndrome and allergic conjunctivitis were investigated.

METHODS

Children aged 6 to 15 years with dry eye symptoms were included. Slit-lamp examinations including tear film break-up time, Schirmer's test, and fluorescent staining were performed, and subjective symptoms were investigated. Patients with allergic conjunctivitis were subjected to skin prick tests.

RESULTS

Tear film break-up time was shorter and the number of symptoms related to dry eyes was higher in pediatric patients with allergic conjunctivitis than in those without allergic conjunctivitis. Patients with allergic conjunctivitis who had higher numbers of positive allergens on the skin prick test also had shorter tear film break-up time.

CONCLUSION

Because pediatric patients with dry eye syndrome tend to complain less about their symptoms than adult patients, dry eye syndrome is commonly overlooked. This study showed that dry eyes tended to be more severe with the presence of allergic conjunctivitis; the more allergens present, the more severe the dry eyes. More attention should be paid to the treatment of pediatric patients with dry eyes accompanied by allergies.

Efficacy and safety of a once-daily sublingual immunotherapy without escalation regimen in house dust mite-induced allergic rhinitis

BACKGROUND

The conventional escalation regimen for sublingual immunotherapy (SLIT) in patients with allergic rhinitis has been proven to be safe and successful in reducing allergic symptoms. However, few studies compared the efficacy and safety between a conventional escalation regimen for SLIT and once-daily SLIT. The aim of the present study was to compare the efficacy and safety of once-daily SLIT without escalation (SLITsE) to conventional escalation therapy (SLITwE).

METHODS

This study was a nonrandomized open label observational study. In total, 153 patients suffering from allergic rhinitis symptoms and sensitized to the perennial house dust mite allergens Dermatophagoides pteronyssinus and Dermatophagoides farinae, were enrolled in this study from July 2008 to December 2009. The patients were divided into 2 groups, SLITwE and SLITsE. Each patient was followed with a diary card on which a symptom score, a rescue medication score, and adverse events were recorded.

RESULTS

All of the nasal symptoms, including rhinorrhea, sneezing, nasal obstruction, itching, and olfactory symptoms, defined as a total nasal symptom score, were reduced after 6 months in both groups (p < 0.05). The rescue medication score, defined as the sum of all of the allergy medications used, also decreased in both groups. Adverse events were similar in both groups, and no major adverse events, such as anaphylaxis, were reported.

CONCLUSION

Once-daily SLITsE was well tolerated and showed safe and comparable efficacy compared with a conventional SLITwE regimen.

Investigating international time trends in the incidence and prevalence of atopic eczema 1990-2010: a systematic review of epidemiological studies

The prevalence of atopic eczema has been found to have increased greatly in some parts of the world. Building on a systematic review of global disease trends in asthma, our objective was to study trends in incidence and prevalence of atopic eczema. Disease trends are important for health service planning and for generating hypotheses regarding the aetiology of chronic disorders. We conducted a systematic search for high quality reports of cohort, repeated cross-sectional and routine healthcare database-based studies in seven electronic databases. Studies were required to report on at least two measures of the incidence and/or prevalence of atopic eczema between 1990 and 2010 and needed to use comparable methods at all assessment points. We retrieved 2,464 citations, from which we included 69 reports. Assessing global trends was complicated by the use of a range of outcome measures across studies and possible changes in diagnostic criteria over time. Notwithstanding these difficulties, there was evidence suggesting that the prevalence of atopic eczema was increasing in Africa, eastern Asia, western Europe and parts of northern Europe (i.e. the UK). No clear trends were identified in other regions. There was inadequate study coverage worldwide, particularly for repeated measures of atopic eczema incidence. Further epidemiological work is needed to investigate trends in what is now one of the most common long-term disorders globally. A range of relevant measures of incidence and prevalence, careful use of definitions and description of diagnostic criteria, improved study design, more comprehensive reporting and appropriate interpretation of these data are all essential to ensure that this important field of epidemiological enquiry progresses in a scientifically robust manner.

Association of the MMP9 gene with childhood cedar pollen sensitization and pollinosis

Matrix metalloproteinase 9 (MMP9) gene has been shown to be involved in the pathogenesis of allergic rhinitis (AR) and asthma. Previous studies suggested that single-nucleotide polymorphisms (SNPs) of the MMP9 gene conferred a risk for childhood asthma. However, whether the SNPs confer a risk for AR has not been previously investigated. The objective of this study was to investigate whether SNPs of the MMP9 gene are associated with risk of seasonal AR (pollinosis), perennial AR and allergen sensitization. A total of 670 school children were recruited in Japan and genotyped for functional polymorphism in the promoter (-1590C/T: rs3918242) and three amino-acid substitutions (R297Q: rs17576; P574R: rs2250889; R668Q: rs17577). Serum levels of total and specific IgE were determined. Disease status and other clinical characteristics of the subjects were investigated using a questionnaire. Associations between the MMP9 SNPs and both AR and serum IgE levels were evaluated. -1590C/T showed significant association with cedar pollinosis (corrected P (Pcor)=0.039). R668Q was in strong linkage disequilibrium (LD) with -1590C/T and showed significant association with cedar pollinosis (Pcor=0.023) and serum cedar pollen-specific IgE level (Pcor=0.022). A haplotype associated with -1590T and 668Q showed a significant association with cedar pollinosis, orchard grass pollinosis and cedar pollen-specific IgE (Pcor=0.0012, Pcor=0.0059 and Pcor=0.0041, respectively). R297Q and P574R were in weak LD with the rest of the SNPs and did not show significant association with disease. Compared with wild-type MMP9 protein (279R-574P-668R), a variant enzyme (279R-574P-668Q) that showed association with pollinosis had lower activity. However, lower enzyme activity was not associated with disease risk because another variant (279Q-574R-668R) showed lower enzyme activity but was not associated with pollinosis. The -1590T allele and its corresponding haplotype was associated with higher promoter activity and with pollen-specific IgE levels and pollinosis, suggesting that -1590C/T may have more impact on sensitization and disease development than R668Q. Our results suggest that the MMP9 gene confers susceptibility to cedar pollinosis in Japanese children. The MMP9 gene may be associated with pollinosis through sensitization processes.

Time trend in the prevalence of adult asthma in Japan: findings from population-based surveys in Fujieda City in 1985, 1999, and 2006

BACKGROUND

The burden of asthma is recognized as an important public health problem worldwide. In most countries, the prevalence of asthma has been reported to increase in the last few decades. However, more recent epidemiological studies have shown that the prevalence of asthma has been flat or even decreasing after the 1990 s in some developed countries. The recent time trend in the prevalence of adult asthma in Japan is unknown.

METHODS

Population-based surveys were conducted three times in the same region, in 1985, 1999, and 2006, at Fujieda City, Shizuoka, Japan, and the results were reported previously. We compared the results of these surveys to reveal the time trend in the prevalence of adult asthma. Although the questionnaires used in these surveys were not exactly the same, the time trend was assessed by comparing the responses to relevant questions between questionnaires.

RESULTS

The prevalences of wheeze following a common cold and dyspneal feeling at night increased significantly from 1985 to 1999 (4.2% to 7.6%, and 3.2% to 5.3%, respectively). The prevalences of lifetime asthma and current asthma also significantly increased from 1999 to 2006 (5.1% to 6.7%, and 1.5% to 3.4%, respectively).

CONCLUSIONS

The prevalences of asthma among adults in Fujieda City consistently increased from 1985 to 2006. There was no evidence that the prevalences were in plateau or decreasing. These findings suggest that more efforts are required to stop the increase in the burden of this disease in Japan.

Vascular cell adhesion molecule-1 expression and signaling during disease: regulation by reactive oxygen species and antioxidants

The endothelium is immunoregulatory in that inhibiting the function of vascular adhesion molecules blocks leukocyte recruitment and thus tissue inflammation. The function of endothelial cells during leukocyte recruitment is regulated by reactive oxygen species (ROS) and antioxidants. In inflammatory sites and lymph nodes, the endothelium is stimulated to express adhesion molecules that mediate leukocyte binding. Upon leukocyte binding, these adhesion molecules activate endothelial cell signal transduction that then alters endothelial cell shape for the opening of passageways through which leukocytes can migrate. If the stimulation of this opening is blocked, inflammation is blocked. In this review, we focus on the endothelial cell adhesion molecule, vascular cell adhesion molecule-1 (VCAM-1). Expression of VCAM-1 is induced on endothelial cells during inflammatory diseases by several mediators, including ROS. Then, VCAM-1 on the endothelium functions as both a scaffold for leukocyte migration and a trigger of endothelial signaling through NADPH oxidase-generated ROS. These ROS induce signals for the opening of intercellular passageways through which leukocytes migrate. In several inflammatory diseases, inflammation is blocked by inhibition of leukocyte binding to VCAM-1 or by inhibition of VCAM-1 signal transduction. VCAM-1 signal transduction and VCAM-1-dependent inflammation are blocked by antioxidants. Thus, VCAM-1 signaling is a target for intervention by pharmacological agents and by antioxidants during inflammatory diseases. This review discusses ROS and antioxidant functions during activation of VCAM-1 expression and VCAM-1 signaling in inflammatory diseases.

Genome-wide association study identifies HLA-DP as a susceptibility gene for pediatric asthma in Asian populations

Asthma is a complex phenotype influenced by genetic and environmental factors. We conducted a genome-wide association study (GWAS) with 938 Japanese pediatric asthma patients and 2,376 controls. Single-nucleotide polymorphisms (SNPs) showing strong associations (P<1×10⁻⁸) in GWAS were further genotyped in an independent Japanese samples (818 cases and 1,032 controls) and in Korean samples (835 cases and 421 controls). SNP rs987870, located between HLA-DPA1 and HLA-DPB1, was consistently associated with pediatric asthma in 3 independent populations (P_combined = 2.3×10⁻¹⁰, odds ratio [OR] = 1.40). HLA-DP allele analysis showed that DPA1*0201 and DPB1*0901, which were in strong linkage disequilibrium, were strongly associated with pediatric asthma (DPA1*0201: P = 5.5×10⁻¹⁰, OR = 1.52, and DPB1*0901: P = 2.0×10⁻⁷, OR = 1.49). Our findings show that genetic variants in the HLA-DP locus are associated with the risk of pediatric asthma in Asian populations.

Asthma is the most common chronic disorder in children, and asthma exacerbation is an important cause of childhood morbidity and hospitalization. Here, taking advantage of recent technological advances in human genetics, we performed a genome-wide association study and follow-up validation studies to identify genetic variants for asthma. By examining 6,428 Asians, we found rs987870 and HLA-DPA1*0201/DPB1*0901 were associated with pediatric asthma. The association signal was stretched in the region of HLA-DPB2, collagen, type XI, alpha 2 (COL11A2), and Retinoid X receptor beta (RXRB), but strong linkage disequilibrium in this region made it difficult to specifically identify causative variants. Interestingly, the SNP (or the HLA-DP allele) associated with pediatric asthma (Th-2 type immune diseases) in the present study confers protection against Th-1 type immune diseases, such as type 1 diabetes and rheumatoid arthritis. Therefore, the association results obtained in the present study could partially explain the inverse relationship between asthma and Th-1 type immune diseases and may lead to better understanding of Th-1/Th-2 immune diseases.

The effect of past food avoidance due to allergic symptoms on the growth of children at school age

BACKGROUND

The influence of food avoidance due to allergic symptoms in infancy on the growth of children at school age has not been well evaluated.

METHODS

To determine the growth of schoolchildren who avoided eggs, milk, or wheat due to immediate allergic symptoms in infancy (food avoiders in infancy) (FAI), a questionnaire on the presence of allergic diseases, as well as present height and weight, was administered to the parents of 14,669 schoolchildren. 11,473 subjects had available data. The height and weight standard deviation scores (HtSDS and WtSDS) and body mass index percentile (BMI percentile) of each subject were calculated.

RESULTS

FAI had significantly lower WtSDS than non-FAI (P = 0.01). Among those with avoidance at age 3 years, those who avoided two or more foods and those who avoided milk had significantly lower HtSDS than their counterparts (P = 0.02 and 0.04, respectively). FAI had a significantly lower prevalence of obesity (P = 0.01) and overweight (P = 0.002), while there was no difference in the prevalence of underweight (P = 0.58), resulting in a significantly higher prevalence of appropriate weight (P = 0.01) compared to non-FAI. Significantly lower prevalence of obesity and overweight was observed even among those who terminated the avoidance by age 3 years.

CONCLUSIONS

FAI were less likely to be obese or overweight, resulting in a higher prevalence of appropriate weight at school age. Further investigation should contribute to better management of food allergy and obesity.

Allergic conjunctivitis and the impact of allergic rhinitis

Although nasal allergy has been prominent in allergy research, ocular allergy is increasingly recognized as a distinct symptom complex that imposes its own disease burden and reduction in patients' quality of life. In the past year, knowledge of the relationships between allergic conjunctivitis and allergic rhinitis has increased. Allergic conjunctivitis is highly prevalent and has a close epidemiologic relationship with allergic rhinitis. Both conditions also exhibit similar pathophysiologic mechanisms. Pathways of communication are thought to increase the likelihood of an inflammatory reaction at both sites following allergen exposure of nasal or ocular tissue. Clinical trials of intranasal therapies have demonstrated efficacy in allergic conjunctivitis and rhinitis. Newer intranasal steroids decrease ocular symptoms, potentially achieving efficacy by suppressing the naso-ocular reflex, downregulation of inflammatory cell expression, or restoration of nasolacrimal duct patency. Proposed pathophysiologic interactions between allergic rhinitis and ocular allergy underscore the need for therapies with efficacy in both symptom sets.

Allergies in Asia: differences in prevalence and management compared with western populations

There is wide variability in the epidemiology and management of childhood asthma and related atopic diseases globally. Urbanized, affluent Western countries tend to have a higher prevalence of these diseases compared with Asian nations. However, recent studies have shown that the prevalence in Asia is increasing, although the rate of increase has slowed in the more developed Asian cities. Some possible causes for these differences are socioeconomic status, degree of urbanization, rates of infection, healthcare practices and genetic factors. Importantly, there are significant differences in the way asthma and allergic diseases are managed within Asia. This is of great concern because of the health implications, as these diseases are some of the most common chronic conditions that affect both adults and children. This review compares the differences in prevalence and management between Asia and the West, and discusses some of the possible reasons behind these variations.