Prevalence of bronchial asthma in schoolchildren in Delhi

Life Course of Asthma

Asthma is a heterogeneous chronic airway disease that can vary over a lifetime. Although broad categories of asthma by severity and type have been constructed, there remains a tremendous opportunity to discover an approach to managing asthma with additional factors in mind. Many in the field have suggested and are pursuing a novel paradigm shift in how asthma might be better managed, considering the life course of exposures, management priorities, and predicted trajectory of lung function growth. This approach will require a more holistic view of prenatal, postnatal, adolescence, hormonal and gender aspects, and the aging process. In addition, the environment, externally and internally, including in one's genetic code and epigenetic changes, are factors that affect how asthma progresses or becomes more stable in individuals. This chapter focuses on the various influences that may, to differing degrees, affect people with asthma, which can develop at any time in their lives. Shifting the paradigm of thought and strategies for care and advocating for public policies and health delivery that focus on this philosophy is paramount to advance asthma care for all.

Association between air pollution, body mass index, respiratory symptoms, and asthma among adolescent school children living in Delhi, India

Background:

Delhi is one of the most polluted cities in the world with annual average ambient PM₁₀ and PM_2.5 levels exceeding the World Health Organization standards by over 15 fold. We aimed to study the prevalence of respiratory and allergic symptoms and asthma among adolescent children living in Delhi (D) and compare it with children living in lesser polluted cities of Kottayam (K) and Mysore (M) located in Southern India.

Methods:

4361 boys and girls between the age group of 13–14 and 16–17 years from 12 randomly selected private schools from D, K, and M were invited to participate. Modified and expanded International Study for Asthma and Allergies in Children (ISAAC) questionnaires (Q) were filled by the students who also performed spirometry using the ultrasonic flow-sensor-based nDD Spirometer.

Results:

3157 students (50.4% boys) completed the Q and performed good quality spirometry. The prevalence of asthma and airflow obstruction among children living in Delhi was 21.7% using the ISAAC Q and 29.4% on spirometry, respectively. This was accompanied by significantly higher rates of self-reported cough, shortness of breath, chest tightness, sneezing, itchy and watery eyes, itchy skin, and eczema among Delhi children (vs. K-M, all P < 0.05). Delhi children were more overweight and obese (39.8% vs. 16.4%, P < 0.0001), and this was the only risk factor that was strongly associated with asthma (odds ratio [OR]: 1.79; confidence interval: 1.49–2.14), with a more pronounced effect in Delhi children (P = 0.04). Forced expiratory volume₁ and Forced vital capacity values were significantly higher in Delhi children (vs. K-M P < 0.0001). Preserved ratio impaired spirometry was more common in K-M children (P < 0.0001).

Conclusion:

Adolescent children living in the polluted city of Delhi had a high prevalence of asthma, respiratory symptoms, allergic rhinitis, and eczema that was strongly associated with a high body mass index (BMI). Our study suggests an association between air pollution, high BMI, and asthma/allergic diseases, which needs to be explored further.

Operational definitions of paediatric asthma used in epidemiological studies: A systematic review

Background

Researchers use different definitions to identify children with asthma in epidemiological surveys. We conducted a systematic review to describe the definitions used in epidemiologic studies for wheeze and asthma in the paediatric population, aimed to inform the development of a uniform definition of paediatric asthma for future epidemiological research.

Methods

We systematically searched terms to identify asthma and/or wheeze among children aged <13 years and published between 1995-2020 across seven databases (MEDLINE, EMBASE, PsycINFO, Global Health, AMED, LILACS and CINAHL). PRISMA guidelines were followed for this review.

Results

We extracted a total of 11 886 records, where 190 met our eligibility criteria and included in the analysis. Among the included studies, 62.1% (n = 118/190) used the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires, predominantly in developing countries (80%, n = 64/80). ‘Wheeze’ was reported in five categories, subdivided by 14 different definitions. “Current wheeze”, defined as caregivers report of wheezing sounds from the chest of the child in the past 12 months and “Wheeze ever”, defined as caregivers’ report of wheezing or whistling in the chest of the child at any previous time, were the most common wheeze category reported in 129 and 95 studies, respectively. Asthma was reported in nine categories using 53 definitions. The most common asthma category was “Asthma ever”, which was reported in 89 studies, based on caregiver statement that the child had asthma in the past.

Conclusion

Definitions of wheeze and asthma for children used in surveys are primarily based on parent-reported clinical features. Studies from developing countries more frequently used the ISAAC definitions to report childhood asthma and wheeze compared to the studies from developed counties. The use of a uniform asthma definition will aid the interpretation of research findings globally.

Trends of sensitization to aeroallergens in patients with allergic rhinitis and asthma in the city of Bursa, South Marmara Sea Region of Turkey

Background/aim

Allergic rhinitis (AR) and asthma are the most common allergic disorders worldwide. Aeroallergens are critical causative factors in the pathogenesis of these disorders and sensitization to aeroallergens differs in various countries and regions. Identification of the most common aeroallergen sensitization is crucial in the diagnosis and management of AR and asthma. We examined the distribution of aeroallergen sensitizations detected by skin prick tests (SPTs) in adult patients with AR and/or asthma in the city of Bursa.

Materials and methods

Five hundred forty-five patients who underwent a SPT and were diagnosed with rhinitis and/or asthma in the Uludağ University Faculty of Medicine’s Department of Immunology and Allergic Diseases Outpatient Clinic from March 2018 to August 2018 were retrospectively evaluated. SPTs with standard extracts including house dust mites, pollens, molds, animal dander, and latex were performed for patients.

Results

A total of 545 patients were included and most of the patients (270; 49.5%) were between 30 and 49 years of age. The prevalence of atopy was 57.9%. The most common aeroallergens detected in SPTs were Dermatophagoides farinae (50%) and D. pteronyssinus (44%), followed by grass-rye mix (43%), grass mix (38.6%), olive (33.2%), and wheat (32.3%). The sensitization to olive pollen was higher in cases of mild asthma (52%), while sensitization to D. farinae was higher in patients with mild and moderate asthma (54.5%, 54.2%) (P < 0.05) .

Conclusions

Our study revealed that house dust mite was the most common sensitizing aeroallergen in patients with AR and asthma while pollens were the most common allergen in patients with only AR. The sensitization to grass and olive pollen was higher in cases of mild asthma than moderate and severe. Regional allergy panels may provide important clinical clues for characteristics and courses of allergic diseases.

Spectrum of Allergens and Allergen Biology in India

The growing prevalence of allergy and asthma in India has become a major health concern with symptoms ranging from mild rhinitis to severe asthma and even life-threatening anaphylaxis. The "allergen repertoire" of this subcontinent is highly diverse due to the varied climate, flora, and food habits. The proper identification, purification, and molecular characterization of allergy-eliciting molecules are essential in order to facilitate an accurate diagnosis and to design immunotherapeutic vaccines. Although several reports on prevalent allergens are available, most of these studies were based on preliminary detection and identification of the allergens. Only a few of these allergen molecules have been characterized by recombinant technology and structural biology. The present review first describes the composition, distribution pattern, and natural sources of the predominant allergens in India along with the prevalence of sensitization to these allergens across the country. We go on to present a comprehensive report on the biochemical, immunological, and molecular information on the allergens reported so far from India. The review also covers the studies on allergy- related biosafety assessment of transgenic plants. Finally, we discuss the allergen-specific immunotherapy trials performed in India.

Air pollution and public health: the challenges for Delhi, India

Mitigating the impact of pollution on human health worldwide is important to limit the morbidity and mortality arising from exposure to its effect. The level and type of pollutants vary in different urban and rural settings. Here, we explored the extent of air pollution and its impacts on human health in the megacity of Delhi (India) through a review of the published literature. The study aims at describing the extent of air pollution in Delhi, the magnitude of health problems due to air pollution and the risk relationship between air pollution and associated health effects. We found 234 published articles in the PubMed search. The search showed that the extent of air pollution in Delhi has been described by various researchers from about 1986 onwards. We synthesized the findings and discuss them at length with respect to reported values, their possible interpretations and any limitations of the methodology. The chemical composition of ambient air pollution is also discussed. Further, we discuss the magnitude of health problem with respect to chronic obstructive pulmonary diseases (COPD), bronchial asthma and other illnesses. The results of the literature search showed that data has been collected in last 28 years on ambient air quality in Delhi, though it lacks a scientific continuity, consistency of locations and variations in parameters chosen for reporting. As a result, it is difficult to construct a spatiotemporal picture of the air pollution status in Delhi over time. The number of sites from where data have been collected varied widely across studies and methods used for data collection is also non-uniform. Even the parameters studied are varied, as some studies focused on particulate matter ≤10 μm in aerodynamic diameter (PM10) and those ≤2.5 μm in aerodynamic diameter (PM2.5), and others on suspended particulate matter (SPM) and respirable suspended particulate matter (RSPM). Similarly, the locations of data collection have varied widely. Some of the sites were at busy traffic intersections, some on the terraces of offices and residential houses and others in university campuses or airports. As a result, the key question of the extent of pollution and its distribution across various parts of the city could be inferred. None of the studies or a combination of them could present a complete picture of the burden of diseases like COPD, bronchial asthma and other allergic conditions attributable to pollution in Delhi. Neither could it be established what fraction of the burden of the above diseases is attributable to ambient air pollution, given that other factors like tobacco smoke and indoor air pollution are also contributors to the causation of such diseases. In our discussion, we highlight the knowledge gaps and in the conclusion, we suggested what research can be undertaken to fill the these research gaps.

Prevalence of bronchial asthma and factors associated with it among higher secondary school children in Ernakulam district, Kerala, Southern India

Context

Bronchial asthma is one of the leading causes of hospitalization and cause of frequent absenteeism among children and adolescents. Studies reporting the prevalence of bronchial asthma among adolescents from India are limited and the available studies report wide geographic variations in the prevalence of bronchial asthma.

Aims

The current study was aimed to estimate the prevalence of bronchial asthma among higher secondary school children and to identify various factors associated with it in Ernakulam district, Kerala, Southern India.

Settings and Design

The study was conducted in Ernakulam district, the industrial capital of Kerala. A school-based cross-sectional study was conducted.

Subjects and Methods

Data were collected from 629 students from 4 randomly selected higher secondary schools using a structured questionnaire. Section on details of respiratory symptoms was adapted from International Union Against Tuberculosis and Lung Disease bronchial symptoms questionnaire.

Statistical Analysis Used

Descriptive statistics was done with frequencies and percentages and confidence intervals (CIs) were calculated. Univariate and multivariate analysis was done for factors associated with bronchial asthma generating odds ratios (ORs) and 95% CIs.

Results

A total of 629 students participated in this study. The prevalence of bronchial asthma was estimated to be 9.9% (95% CI = 7.53%-12.27%). Students residing in a rural area (adjusted OR = 1.95, 95% CI = 1.10-3.46) having family history of bronchial asthma (adjusted OR = 2.84, 95% CI = 1.57-5.11) and usual exposure to friend's smoke (adjusted OR = 2.16, 95% CI = 1.17-3.97) were significantly associated with bronchial asthma.

Conclusions

The prevalence of bronchial asthma was higher among higher secondary school students of Ernakulam district. Considering high prevalence and its contributions to morbidity and mortality, a comprehensive program to tackle the issue of chronic respiratory diseases may be needed. The issue of active and passive smoking at schools exists and need to be resolved.

Induced Sputum Nitrite Levels Correlate with Clinical Asthma Parameters in Children Aged 7-18 Years with Mild to Moderate Persistent Asthma

PURPOSE

The objective of this study is to measure levels of nitrites in induced sputum in children with asthma and correlate it with clinical asthma parameters.

METHOD

This prospective observational study was done in PGIMER, Dr. Ram Manohar Lohia Hospital, New Delhi, on 91 children aged 7-18 years with mild and moderate persistent asthma. Patients were specifically evaluated for five clinical parameters of asthma (i.e. Days of acute exacerbations, use of salbutamol as rescue medication, emergency visits, nights with cough, days of school absence) and induced sputum nitrite levels was done at the time of enrollment and 3 months after treatment with inhaled budesonide.

RESULTS

The mean age of subjects was 10.79 ± 2.563yrs. Six (6.59%) patients were not able to perform induced sputum, eighty five (93.41%) patients were suitable for data analysis. There was significant reduction in sputum nitrite levels from 33.42 ± 22.04nmol/ml at enrollment to 11.72 ± 5.61 nmol/ml (P < 0.0005) after 3 months of inhaled budesonide therapy. Significant positive correlation was found between reduction in sputum nitrite level and control of asthma symptoms: Days of acute exacerbations(r value = 0.548, P value = 0.0001), Days of salbutamol use as rescue medication (r value = 0.431, P value =< 0.0001), Number of emergency visits(r value = 0.414, P value = 0.0001), Nights with cough (r value = 0.259, P value = 0.0169), Days of school absence(r value = 0.411, P value = 0.0001). Sputum nitrite levels were significantly higher in moderate persistent asthmatics as compared to mild at the time of enrollment (P < 0.0005), which shows that induced sputum nitrite levels correlate with asthma severity.

CONCLUSIONS

This study confirms that nitrites in induced sputum correlate well with clinical asthma parameters and asthma severity in children and is a simple, non invasive, and cheap method which can be used as a parameter for monitoring of asthma.

Medication use in Indian children with asthma: the user's perspective

BACKGROUND AND OBJECTIVE

Despite the high prevalence of asthma in children, there has been limited research into patient perception of medication use, particularly in the developing world. This study therefore aimed to carry out an in-depth exploration of the views of carers and children with asthma on asthma medication use.

METHODS

Grounded theory approach was used to conduct semistructured qualitative interviews in a purposive convenience sample of parents and children with asthma. The participants were recruited from two specialty hospitals in New Delhi, India. Interviews were tape-recorded, transcribed verbatim and thematically analysed.

RESULTS

Twenty children (7-12 years old) with asthma and their parent or carer were interviewed in July 2011. Major reported issues included poor parent and child understanding of disease and medications. Fears, misinformed beliefs and lack of self-management skills were apparent. Child self-image, resistance to medication use and lack of responsibility in medication taking were themes that emerged from child interviews.

CONCLUSIONS

This is one of the first research studies exploring the viewpoint of children with asthma about their medications. Resource constraints dictate a pragmatic paternalistic approach by physicians which, in contrast to patients in westernized nations, seems to be acceptable and satisfactory to Indian patients (carers).

Indoor fungal concentration in the homes of allergic/asthmatic children in Delhi, India

Allergy to fungi has been linked to a wide range of illnesses, including rhinitis and asthma. Therefore, exposure to fungi in home environment is an important factor for fungal allergy. The present study was aimed to investigate types of airborne fungi inside and outside the homes of asthmatic children and control subjects (nonasthmatic children). The dominant fungi were evaluated for their quantitative distribution and seasonal variation. The air samples were collected from indoors and immediate outdoors of 77 selected homes of children suffering from bronchial asthma/allergic rhinitis using Andersen volumetric air sampler. The isolated fungal genera/species were identified using reference literature, and statistical analysis of the dominant fungi was performed to study the difference in fungal concentration between indoor and immediate outdoor sites as well as in between different seasons. A total of 4423 air samples were collected from two indoor and immediate outdoor sites in a 1-year survey of 77 homes. This resulted in the isolation of an average of 110,091 and 107,070 fungal colonies per metric cube of air from indoor and outdoor sites, respectively. A total of 68 different molds were identified. Different species of Aspergillus, Alternaria, Cladosporium, and Penicillium were found to be the most prevalent fungi in Delhi homes, which constituted 88.6% of the total colonies indoors. Highest concentration was registered in autumn and winter months. Total as well as dominant fungi displayed statistically significant differences among the four seasons (p < 0.001). The largest number of isolations were the species of Aspergillus (>40% to total colony-forming units in indoors as well as outdoors) followed by Cladosporium spp. Annual concentration of Aspergillus spp. was significantly higher (p < 0.05) inside the homes when compared with outdoors. Most of the fungi also occurred at a significantly higher (p < 0.001) rate inside the homes when compared with immediate outdoors. Asthmatic children in Delhi are exposed to a substantial concentration of mold inside their homes as well as immediate outdoor air. The considerable seasonal distributions of fungi provide valuable data for investigation of the role of fungal exposure as a risk for respiratory disorders among patients suffering from allergy or asthma in Delhi.

Effect of indoor air pollution from biomass and solid fuel combustion on prevalence of self-reported asthma among adult men and women in India: findings from a nationwide large-scale cross-sectional survey

OBJECTIVES

Increasing prevalence of asthma in developing countries has been a significant challenge for public health in recent decades. A number of studies have suggested that ambient air pollution can trigger asthma attacks. Biomass and solid fuels are a major source of indoor air pollution, but in developing countries the health effects of indoor air pollution are poorly understood. In this study we examined the effect of cooking smoke produced by biomass and solid fuel combustion on the reported prevalence of asthma among adult men and women in India.

METHODS

The analysis is based on 99,574 women and 56,742 men aged between 20 and 49 years included in India's third National Family Health Survey conducted in 2005-2006. Effects of exposure to cooking smoke, determined by the type of fuel used for cooking such as biomass and solid fuels versus cleaner fuels, on the reported prevalence of asthma were estimated using multivariate logistic regression. Since the effects of cooking smoke are likely to be confounded with effects of tobacco smoking, age, and other such factors, the analysis was carried out after statistically controlling for such factors.

RESULTS

The results indicate that adult women living in households using biomass and solid fuels have a significantly higher risk of asthma than those living in households using cleaner fuels (OR: 1.26; 95%CI: 1.06-1.49; p = .010), even after controlling for the effects of a number of potentially confounding factors. Interestingly, this effect was not found among men (OR: 0.98; 95%CI: 0.77-1.24; p = .846). However, tobacco smoking was associated with higher asthma prevalence among both women (OR: 1.72; 95%CI: 1.34-2.21; p < .0001) and men (OR: 1.35; 95%CI: 1.49-2.25; p < .0001). Combined effects of biomass and solid fuel use and tobacco smoke on the risk of asthma were greater and more significant in women (OR: 2.16; 95%CI: 1.58-2.94; p < .0001) than they were in men (OR: 1.34; 95%CI: 1.04-1.72; p = .024).

CONCLUSIONS

The findings have important program and policy implications for countries such as India, where large proportions of the population still rely on polluting biomass fuels for cooking and heating. Decreasing household biomass and solid fuel use and increasing use of improved stove technology may decrease the health effects of indoor air pollution. More epidemiological research with better measures of smoke exposure and clinical measures of asthma is needed to validate the findings.

Asthma in Black African, Black Caribbean and South Asian adolescents in the MRC DASH study: a cross sectional analysis

Background

Ethnic differences in the prevalence of asthma among children in the UK are under-researched. We aimed to determine the ethnic differences in the prevalence of asthma and atopic asthma in children from the main UK ethnic groups, and whether differences are associated with differential distributions in social and psychosocial risk factors.

Methods

6,643 pupils aged 11-13 years, 80% ethnic minorities. Outcomes were asthma/wheeze with (atopic) and without hay fever/eczema. Risk factors examined were family history of asthma, length of residence in the UK, socioeconomic disadvantage, tobacco exposure, psychological well-being, and body mass index (BMI).

Results

There was a pattern of lower prevalence of asthma in Black African boys and girls, and Indian and Bangladeshi girls compared to White UK. The overall prevalence was higher in Mixed Black Caribbean/White boys, with more atopic asthma in Black Caribbean boys and Mixed Black Caribbean/White boys due to more hayfever. Poor psychological well-being and family history of asthma were associated with an increased risk of asthma within each ethnic group. UK residence for ≤ 5 years was protective for Black Caribbeans and Black Africans. Increased BMI was associated with an increased reporting of asthma for Black Africans. Adjustments for all variables did not remove the excess asthma reported by Black Caribbean boys (atopic) or Mixed Black Caribbean/White boys.

Conclusion

The protective effect of being born abroad accounted for ethnic differences in some groups, signalling a role for socio-environmental factors in patterning ethnic differences in asthma in adolescence.

Prevalence of bronchial asthma in Indian children

BACKGROUND

The prevalence of childhood bronchial asthma and allergic disease has increased in developed countries. Studies have identified asthma among Indian children. Still, there is paucity of information on the overall prevalence of childhood asthma in India.

OBJECTIVE

To assess time trends and the overall prevalence rate of bronchial asthma among Indian children.

MATERIALS AND METHODS

Literature search for data sources was done through an extensive search in indexed literatures and website-based population survey reports. Fifteen epidemiological studies were identified on the development of asthma in Indian children from 300 potentially relevant articles. A broad criterion to define both allergic and non-allergic descriptions of asthma in Indian children was formed. Moreover, in the absence of universally accepted criteria by reporting of prevalence by researchers, weighted average data was considered during calculations of prevalence rates, irrespective of the criteria for diagnosis. Statistical analyses used were mean and median.

RESULTS

Wide differences in samples, primary outcome variables, lack of consistency in age category, rural-urban variation, criteria for positive diagnosis, and study instruments confounded the outcome variables. The mean prevalence was 7.24 +/- SD 5.42. The median prevalence was 4.75% [with IQR = 2.65 - 12.35%]. Overall weighted mean prevalence was found to be 2.74. Childhood asthma among children 13 - 14 years of age was lower than the younger children (6 - 7 years of age). Urban and male predominance with wide inter-regional variation in prevalence was observed.

CONCLUSIONS

Our findings indicate that the burden of bronchial asthma in Indian children is higher than was previously understood.

Current immunological approaches for management of allergic rhinitis and bronchial asthma

A large population world over is affected with allergic diseases and asthma. Pharmacotherapy for allergic diseases and asthma is effective in controlling symptoms but on discontinuation of medication, symptoms reoccur. In contrast, immunotherapy modifies and corrects the underlying pathological immune responses in an antigen-specific manner. Immunotherapy shows an increase in IgG (blocking antibody) that competes with IgE for allergen, inhibiting the release of inflammatory mediators. Recent studies suggest that immunotherapy acts by modifying CD4+ T-cell responses either by immune deviation, T-cell anergy and/or both. Current immunological approaches for management of allergies and asthma involve immunization with native allergen, modified allergen, peptides/cDNA of allergen, anti-IgE, adjuvants coupled allergen, including immunostimulatory DNA sequences, cytokines, and bacterial products. These approaches modulate the immune response and are intended to give long-term benefit.

Bronchial asthma: the Indian scene

PURPOSE OF REVIEW

Although asthma is a global disease, there are important differences in epidemiology, clinical spectrum and management practices in India. Some of these issues have been reviewed in this article.

RECENT FINDINGS

The prevalence of 'ever asthma' was reported in 2.4% in a population study on 73,605 individuals conducted simultaneously at four major centres in India with the use of a single definition and uniform methodology employing a validated questionnaire. Of the several risk factors which were found to be significant, exposure to environmental tobacco smoke during childhood alone or both during childhood and adulthood was important in the development of and in increasing morbidity from asthma. Many other triggers and risk factors which include local aeroallergens and air pollutants have been identified. Allergic bronchopulmonary aspergillosis is an important cause of difficult to treat asthma and almost half of these patients receive antitubercular treatment at some stage. Simplified consensus guidelines based on international guidelines and local practices have been developed for use at the primary and secondary levels of healthcare.

SUMMARY

The prevalence of asthma in India is somewhat similar to that seen in other Asian countries. Consensus management guidelines adapted from standard international guidelines adequately address the local concerns and issues.

Sensitization to blackgram in patients with bronchial asthma and rhinitis: clinical evaluation and characterization of allergens

BACKGROUND

Legumes are important causative agents of type I hypersensitivity in south Asia and Europe but such studies are lacking in Indian population. The present study investigates blackgram sensitization in asthma and rhinitis patients and identifies immunoglobulin E (IgE)-binding proteins.

METHODS

Respiratory allergy patients were evaluated using standard questionnaire and skin prick tests (SPT) with common foods and aeroallergens. Blackgram-specific IgE level was estimated by enzyme-linked immunosorbent assay (ELISA) and sensitization was established by a double-blind, placebo-controlled food challenge (DBPCFC). The cross-reactivity of blackgram with other legumes was studied by immunobiochemical methods.

RESULT

Of 816 patients, 35 gave history of blackgram hypersensitivity. From these, 16 patients were SPT positive and 14 showed elevated specific IgE (three times of negative control) to blackgram. DBPCFC established blackgram sensitivity in four of 14 patients. Immunoblotting with individual patient's sera recognized eight most prevalent allergens of 78, 56, 47, 43, 40, 30, 28 and 16 kDa. Roasted blackgram showed six major allergens whereas 47, 43 and 28 kDa proteins retained IgE reactivity upon boiling. Blackgram extract required 14 ng of self protein for 50% ELISA inhibition whereas roasted and boiled blackgram required 16 and 120 ng protein. ELISA and immunoblot inhibition show partial inhibition to blackgram proteins by lentil, limabean and pea.

CONCLUSION

Blackgram induces IgE-mediated reactions in 1.7% of asthma and rhinitis patients and contains eight major IgE-binding components, of which six retained IgE reactivity after roasting. Blackgram shares allergenicity with lentil and limabean.

Prevalence of asthma and asthma-like symptoms in inner-city schoolchildren

This study investigates the prevalence of asthma and asthma-related symptoms in New Orleans inner-city schoolchildren. A cross-sectional survey of 1535 elementary, middle, and high school children (aged 5-18) was conducted by using the International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire. Lifetime prevalence of wheezing was 39.4%, and lifetime prevalence of asthma was 24.4%. Wheezing during the previous 12 months was reported by 25.7% of the sample. Twenty-one percent of respondents reported having one or more attacks of wheezing per year, with 5.6% reporting four or more attacks per year. Many participants reported sleep disturbance (15.4%), with 6.2% reporting sleep disturbance more than once a week. The 12-month rate of speech limitation due to asthma exacerbation was 6.6%. Exercise-induced asthma was reported by 16.9% of the students, and nocturnal cough (not associated with cold) was reported by 27.3%. Overall, boys reported higher rates of symptoms than girls, and younger children (aged 6-7) reported greater symptoms than older children (aged 13-14). These findings show that prevalence of asthma in this population is elevated, and the ISAAC written questionnaire successfully identified inner-city children at risk for asthma in New Orleans.

Family history as a predictor of asthma risk

Asthma, one of the most important chronic diseases of children, disproportionately affects minority and low-income children. Many environmental risk factors for asthma have been identified, including animal, mite, and other allergens; cigarette smoke; and air pollutants. Genetics also play an important causative role, as indicated by familial aggregation and the identification of candidate genes and chromosomal regions linked to asthma risk. Using a positive family history of asthma to identify children at increased risk could provide a basis for targeted prevention efforts, aimed at reducing exposure to environmental risk factors. To assess the predictive value of family history as an indicator of risk for childhood asthma, we reviewed population-based studies that evaluated family history of asthma and atopic disease in children with asthma. Our search identified 33 studies from all geographic regions of the world for review. The studies varied in definitions of positive family history and asthma phenotype and used study populations with asthma prevalence ranging from 2% to 26%. Nevertheless, family history of asthma in one or more first-degree relatives was consistently identified as a risk factor for asthma. In ten studies, sensitivity and predictive value of a positive family history of asthma could be calculated: sensitivity ranged from 4% to 43%, positive predictive value from 11% to 37%, and negative predictive value from 86% to 97%. Although a positive family history predicts an increased risk of asthma, it identifies a minority of children at risk. Positive family history may have utility in targeting some individual prevention efforts, but the low positive predictive value limits its value as a means to direct environmental remediation efforts.

Prevalence of asthma symptoms among the adult population in the city of Mashhad (north-east of Iran)

OBJECTIVE

Although there is evidence of worldwide variation in the prevalence of asthma, the prevalence of asthma in adult populations in Iran is not known.

METHODS

We studied the prevalence of asthma symptoms among the adult population (aged 20 years and over) in the city of Mashhad using a questionnaire. A total of 5579 subjects, comprising 2835 males and 2744 females, were interviewed by trained medical students. The following were used as asthma symptoms in the questionnaire: recurrent wheeze, recurrent cough or tightness at rest, night cough and wheeze or cough during exercise. Subjects with two symptoms or who had been previously diagnosed with asthma were considered as having asthma.

RESULTS

The results showed that 158 subjects (2.8%), comprising 69 males (2.4%) and 89 females (3.2%), had asthma. The proportion of subjects with a family history of asthma (40.5%), a history of allergy (43.7%) and a smoking habit (24.5%) was significantly higher than in normal subjects. Of the subjects determined to have asthma, 120 (76%) had been previously diagnosed as having asthma and were under treatment. However, only 65 subjects (41.1%) were currently under treatment.

CONCLUSION

These results suggested a 2.8% prevalence of asthma among the adult population in the city of Mashhad, most of whom had been previously diagnosed and were under treatment.

Asthmatic children and risk factors at a province in the southeast of Turkey

BACKGROUND

The prevalence of asthma appears to be on the increase and the risk factors are not well established. Environmental and demographic characteristics of asthmatic children were investigated to identify the risk factors accompanying asthma.

METHODS

140 asthmatic children aged at 3-15 years were compared with 96 age-matched control subjects admitted to the paediatric outpatient clinics of Dicle University Hospital. Information about the children were obtained from parents and patients'charts.

RESULTS

Patients with asthma were most frequently admitted in May-June and November-January months. Association of the disease with allergic rhinitis was found in 84 children (60 %), allergic conjunctivitis in 63 (45 %), atopic dermatitis in 29 (21 %) and gastrointestinal symptoms in 18 (13 %). Mean age of the cases was 6.8 3.3 and 6.9 3.2 years (p > 0.05); male to female ratios were 91/49 and 43/53 (p = 0.002) in the study and control groups, respectively. There were significant differences at number of cases stated to have any symptoms induced by air pollution (25.6 %, 3.1 %, p < 0,001), exercise (47.5 %, 4.2 %, p < 0.001) and cold exposure (33 %, 15.6 %, p = 0.03), but not by damp, dust, indoor smoking, foods, drugs, and animal contact (p > 0.05) between the study and the control groups, respectively. Family history of atopy was 66 % and 8.4 %, (p < 0.001) in the study and control groups, respectively. Family crowding index, duration of breast feeding, parental education and number of consanguineous married parents were not different between both groups. History of upper respiratory tract infections were more frequent in asthmatic children than controls. Children with an earlier age of onset (</= 5 years) in the study group was more frequently associated with allergic rhinitis in comparison with the asthmatic children with an age of onset > 5 years.

CONCLUSIONS

Many risk factors, both individual and environmental are associated with asthmatic children in Diyarbakr. Among many risk factors that aggrevating asthma in children in Diyarbakr, air pollution, cold exposure and upper respiratory infections are preventable.

Risk factors for development of bronchial asthma in children in Delhi

BACKGROUND

Information on the magnitude of the problem of childhood asthma in India and the factors influencing its occurrence is inadequate.

OBJECTIVE

To measure the prevalence of asthma in schoolchildren in Delhi and study the factors determining its occurrence.

METHODS

A questionnaire-based study carried out in nine randomly selected schools in Delhi. The age range was 5 to 17 years. The questionnaires were distributed to all the children (n = 21,367) for answering by either parent. The key questions relate to complaints of recurrent wheezing in the past, during the immediate last 1-year, and also wheezing exclusively induced by exercise or colds. In all, 19,456 questionnaires were received back (response rate 91%). Out of these, 18,955 were complete and analyzed.

RESULTS

The prevalence of current asthma was 11.9% while past asthma was reported by 3.4% of children. Exclusive exercise-induced asthma was reported by 2.1% while that associated with colds by 2.4% of children. Boys had a significantly higher prevalence of current asthma as compared with girls (12.8% and 10.7%, respectively). Multiple logistic regression analysis showed that male sex, a positive family history of atopic disorders, and the presence of smokers in the family were significant factors influencing the development of asthma while economic class, air pollution (total suspended particulates), and type of domestic kitchen fuel were not.

CONCLUSIONS

The prevalence of current asthma in children in Delhi is 11.9%. Significant risk factors for its development are male sex, a positive family history of atopic disorders, and the presence of smokers in the family.