Gender analysis in acute bronchiolitis due to respiratory syncytial virus

It is reasonable to compare immune reactions between boys and girls because many infections in the early stages are predominant in males. A relationship between immunomodulatory effects of sex hormone surge in boys at early months and infectious diseases is still unclear. We compared clinical features between boys and girls who suffered from wheezing that was initially triggered by acute respiratory syncytial virus (RSV) bronchiolitis. For systemic immune response evaluation, white blood cell (WBC) count, blood eosinophil count, and serum C-reactive protein (CRP) were measured. For local inflammation evaluation, scores for eosinophils and neutrophils in sputum were evaluated microscopically. Patients consisted of 90 boys and 51 girls. Most children were under 6 months of age. WBC counts and serum CRP levels were significantly increased in girls compared with boys. Blood eosinophilia at the acute stage was rarely observed in children after 6 months of age. For local response evaluation, sputum specimens obtained from 42 boys and 29 girls were microscopically examined. Sputum eosinophil score of 2+ and more was observed in boys (6/42) exclusively. In contrast, sputum neutrophilia was commonly observed in boys and girls. From a follow-up study, we confirmed that 28 children with RSV bronchiolitis showed wheezing episodes afterwards. However, their blood and sputum eosinophilia during RSV bronchiolitis did not reflect their subsequent wheezing. We speculated that gender-specific responses to RSV infection might account for male susceptibility. Differences in RSV pathogenicity between boys and girls should be further investigated in terms of asthma progression.     

Age and sex as factors of response to RSV infections among those with previous history of wheezing

Although enhanced immune reaction caused by the respiratory syncytial virus (RSV) in allergen-sensitized animal model has been reported, RSV illnesses in children already sensitized or having recurrent wheezing episodes have not been completely studied. In addition, the reason for male dominances in RSV infection at young ages was also inconclusive. Therefore, gender analysis in recurrent wheezing children with RSV infection can shed light on asthma pathogenesis. We studied the clinical features and the laboratory data of RSV infections in children who had recurrent wheezing histories. The subjects with RSV infection consisted of 98 boys and 58 girls. The children under 4 yr of age were 123 (78.8%) in number. Children with pneumonia were 78 and those with febrile episode were 119. Children above 1 yr of age were highly sensitized with mite antigen (75/96, 78.1%). The clinical symptoms and signs differed according to their ages. Children in each age group behaved differently in their immune reaction to RSV. Above all, 3-yr-old children deteriorated clinically during acute RSV infection, accompanied by transient elevated C-reactive protein (CRP) and suppressed blood eosinophil counts. Clinical features differed in several points between boys and girls. In general, the white blood cell count and the CRP levels were higher in girls in every age group. Blood eosinophil counts at the acute illness were significantly higher in boys than girls aged 2 and 3< yr. Age and gender comparison in already sensitized children might suggest a clue to asthma pathogenesis.     

Development of specific immunoglobulin E in coughing toddlers: A medical records review of symptoms in general practice

The aim of this study was to study whether young children, originally immunoglobulin E (IgE) negative and who became sensitized to specific inhalation allergens, presented more frequently to their general practi‐tioner (GP) with other allergy‐ and asthma‐related symptoms than children who remained IgE negative. It was also investigated whether asthma was diagnosed more often in children who developed IgE to inhalant allergens. Coughing children, 1–5 years of age, visiting the participating GPs, were tested for IgE antibodies to mites, dogs, and cats by using radioallergosorbent testing (RAST). All IgE‐negative (RAST < 0.2 IU/ml) children were re‐tested after 2 years. The medical records of 162 children were reviewed on asthma‐ and allergy‐related symptoms and on prescribed medication. After 30 months, 27 of the 162 children (17%) had become IgE positive for one or more allergens. Most children (93%) had visited their GP for treatment of respiratory symptoms during this period. However, the children who had become IgE positive had visited their GP more often than the children who remained IgE negative. Differences in visits were seen for: shortness of breath (52% IgE‐positive vs. 19% IgE‐negative children, respectively), wheeze (37% vs. 17%), allergic rhinitis (33% vs. 16%), and pneumonia (22% vs. 8%), but not for coughing (89% vs. 88%). The IgE‐positive children were more frequently diagnosed by their GP as having asthma (48%) than were the IgE‐negative children (23%). In a multivariate analysis, indicators of becoming IgE positive were: a visit for shortness of breath (odds ratio [OR] = 6.9; 95% confidence interval [CI] = 2.1–23.1) and two or more visits for wheeze (OR = 6.0; 95% CI = 1.9–19.2), adjusted for breast‐feeding, age, and asthma or allergy in the family. The positive predictive value (PPV) of being IgE positive with a diagnosis of asthma was 90% (whereas the negative predictive value was 48.0%) for a child attending their GP for treatment of wheeze. For recurrent coughing (six or more visits) and shortness of breath, the PPVs were 73% and 71%, respectively. The development of sensitization to common inhalant allergens is associated with specific allergy and asthma‐related symptoms in young children. IgE‐positive children were more frequently diagnosed as having asthma by their GP. This implies that in general practice it is possible to detect children at high risk for developing allergic asthma early in life by their respiratory symptoms and by subsequent testing for specific IgE to inhalant allergens.     

Wheezing requiring hospitalization in early childhood: Predictive factors for asthma in a six-year follow-up

Although asthma is common after wheezing in early childhood, the risk factors for and the prevention of later asthma are poorly understood. During the present follow-up study, a range of possible predictive factors for school-age asthma was evaluated. The study group consisted of 82 children hospitalized for wheezing at age < 2 years in 1992–93. The baseline data were collected on entry to the study. In 1999, the children were re-examined at the median age of 7.2 years. A structured questionnaire was applied to chart the symptoms suggestive of asthma, and the children were examined clinically. An exercise challenge test, as well as skin prick tests (SPT) to common inhalant allergens, was performed. Asthma was present in 33 (40%) children, 30 (91%) having continuous medication for asthma. The significant asthma-predictive factors, present on entry to the study, were blood eosinophilia (p = 0.0008), atopic dermatitis (p = 0.0089), elevated total serum immunoglobulin E (IgE) (p = 0.0452), and a history of earlier episodes of wheezing in infancy (p = 0.0468). SPT positivity in early childhood was also associated with school-age asthma (p = 0.002). In contrast, respiratory syncytial virus (RSV) identification during the index episode of wheezing played a minor role as a predictive factor for asthma. In conclusion, if hospitalization for wheezing occurs in infancy, more than every third child will suffer from asthma at early school age; the risk is significantly increased with recurrent wheezing in infancy and the development of allergic manifestations.     

Persistent nocturnal cough in childhood: a population based study.

A cross sectional epidemiological study was carried out to investigate the validity of persistent nocturnal cough (PNC) as an independent marker of childhood asthma. A screening questionnaire on respiratory symptoms was applied to 4003 children attending primary schools in Aberdeen, after which 799 symptomatic children and a random selection of 229 asymptomatic children were invited to attend for a diagnostic interview. Six hundred and seven (359 boys and 248 girls) symptomatic children and 135 asymptomatic children (57 boys and 78 girls) were selected from the screening questionnaires. Of 607 children with respiratory symptoms when interviewed, 27 (nine boys and 18 girls) had isolated PNC, and 97 (51 boys and 46 girls) had multiple symptoms (polysymptomatic asthma). The incidence of prematurity was highest in the group with PNC (19%). The prevalence of hay fever in children with PNC (11%) was similar to that of the asymptomatic group (15%) and less than that in the group with polysymptomatic asthma (41%). Eczema was twice as common in the PNC (19%) as in the asymptomatic children (10%) but only half as common in the polysymptomatic asthma group (35%). The prevalence of a parental history of hay fever was similar in all three groups. The prevalence of a parental history of eczema was similar in the PNC (7%) and asymptomatic (7%) groups but higher in the polysymptomatic asthma group (22%). The prevalence of a history of parental asthma was 30% in children with PNC, 13% in the asymptomatic group, and 42% in those with polysymptomatic asthma. The parents of three (11%) children with PNC were aware of a diagnosis of asthma; two of these children (7%) were on inhaled bronchodilator treatment and one (4%) was on a slow release theophylline preparation. Using a stepwise discriminant analysis procedure, in 18 (67%) children with PNC predicted membership was in the asymptomatic group and only nine (33%) children with PNC were grouped into the polysymptomatic asthma category. It is concluded that the clinical features of children with PNC resembled those of the asymptomatic population more closely than those of the polysymptomatic asthmatic population. In this age group PNC, in the absence of wheeze, shortness of breath or tightness in the chest, is likely to be a manifestation of atypical or hidden asthma in only a minority of cases.     

Prevalence and severity of asthma,rhinitis, and atopic eczema: the north east study

Using the international study of asthma and allergies in childhood (ISAAC) questionnaire, 3000 children aged 6-7 years from various schools in the north east of England were studied. In this population, the lifetime prevalence rates of various symptoms and diagnoses were: wheezing, 29.6%; atopic eczema, 27.8%; rhinitis, 23.1%; and self reported asthma, 22.7%. Rhinitis was reported by 44% and 40% of boys and girls with asthma, respectively. Atopic eczema was reported by 46% of both boys and girls with asthma. The prevalence rates of reported asthma, and of symptoms suggestive of asthma, were higher than those reported from studies conducted on UK children in 1992.     

Prevalence and severity of asthma, rhinitis, and atopic eczema: the north east study.

Using the international study of asthma and allergies in childhood (ISAAC) questionnaire, 3000 children aged 6-7 years from various schools in the north east of England were studied. In this population, the lifetime prevalence rates of various symptoms and diagnoses were: wheezing, 29.6%; atopic eczema, 27.8%; rhinitis, 23. 1%; and self reported asthma, 22.7%. Rhinitis was reported by 44% and 40% of boys and girls with asthma, respectively. Atopic eczema was reported by 46% of both boys and girls with asthma. The prevalence rates of reported asthma, and of symptoms suggestive of asthma, were higher than those reported from studies conducted on UK children in 1992.     

Computer game for inner-city children does not improve asthma outcomes.

INTRODUCTION: The purpose of this randomized control trial was to evaluate the effects of a computer-assisted instructional (CAI) game on asthma symptoms (eg, coughing, wheezing, shortness of breath, and nighttime awakenings) in 7- to 12-year-old inner-city children over 12 weeks. METHOD: A CAI that focused on reducing environmental irritants/allergens and the correct use of prescribed medications to prevent asthma symptoms was used with 101 children (56 in the intervention group and 45 in the control group). The primary outcome evaluated a change in children's asthma symptoms as measured by responses to nine symptom questions in Juniper's Pediatric Asthma Quality of Life Questionnaire (PAQOL) and measurements of lung function. RESULTS: No significant changes in asthma symptoms occurred between the two groups before and after the intervention. No significant changes were noted in PAQOL scores for activities, emotions, and total PAQOL score, lung function measurements, and asthma severity between the two groups. Asthma knowledge of both groups was high before intervention, but there were no significant changes between groups after the intervention. DISCUSSION: Findings indicate that this CAI game was not effective in improving asthma symptoms in this group of children.     

Time trend for the prevalence of asthma among school children in a Swedish district in 1985–2005

Aim: To assess the temporal trend for asthma and asthma-like symptoms over a period of 20 years.
Method: Repeated cross-sectional surveys with identical study design were carried out among all school children (7–16 years) in a well-defined area in Sweden in 1985, 1995 and 2005.
Results: In 2005, the parents of 1110 out of 7825 children (14.2%) answered yes to a screening question on asthmatic symptoms. Of these, 783 out of 1110 (70.5%) replied to a postal questionnaire with detailed questions concerning symptoms and asthma management. The rate of affirmative response to the screening question was unchanged between 1995 and 2005. However, the percentage of children with wheezing or three or more asthma-like symptoms decreased, whereas the percentage of children with physician-diagnosed asthma increased steadily since 1985. The number of reported symptoms was closely associated with the number of days with physical restriction. The annual sale of inhaled steroids from local pharmacies was stable between 1995 and 2005.
Conclusion: The increase in asthmatic symptoms in school children has peaked. Reduced severity of symptoms and divergent trends for wheezing and physician-diagnosed asthma suggest an increased awareness of asthma with improved management of the symptoms. However, differences in trends between allergic and nonallergic asthma could not be excluded.     

Bacterial colonization in respiratory secretions from acute and recurrent wheezing infants and children

Lower respiratory tract infection in childhood often results in airway obstruction, characterized by wheezing. However, contribution of bacterial colonization to the wheezy state in children remains unclear. Wheezing and non-wheezing children requiring hospitalization were classified into three groups: (i) wheezing children having a past history of recurrent wheezing; (ii) wheezing children without such history; and (iii) non-wheezing children as control subjects. Respiratory secretions as sputum were analyzed microscopically, and cultured. Cultured pathogenic bacterial species in sputum were categorized into two subgroups according to their amounts, i.e., dominant and non-dominant amounts of colonies. Incidence of bacterial colonization and wheezing were assessed. Hospitalized children were mainly 1- to 2-yr old, and rapidly decreased in number for older ages. Children in the three groups belonged to different clinical entities. Children in the recurrent wheezing group were highly sensitized to mite allergens, and still required hospitalization after 2 yr of age. Incidence of bacterial colonization was similar between the three groups. Dominant and non-dominant amounts of bacterial colonization were 170/997 (17.1%) and 170/997 (17.1%), respectively, in the recurrent wheezing group; 28/146 (19.2%) and 35/146 (24.0%), respectively, in the acute wheezing group; and 15/56 (26.8%) and 7/56 (12.5%), respectively, in the non-wheezing group. Regardless of the presence of wheezing, bacterial colonization commonly occurred at a young age in the three groups. In recurrent wheezing children, boys (122/611, 20.0%) carried non-dominant amounts of bacteria more frequently than girls (48/386, 12.4%) (p < 0.01). Boys showed predominant wheezing and susceptibility to bacterial colonization. Assessment of bacterial colonization allowed us to characterize asthma onset and outgrowth in childhood.     

Bottle feeding and exposure to Toxocara as risk factors for wheezing illness among under-five Amazonian children: a population-based cross-sectional study

We investigated the prevalence and risk factors for wheezing and asthma in young Amazonian children. A population-based cross-sectional survey of 606 children aged 6-59 months was performed in two small towns in Acre State, Northwestern Brazil. Information on outcome variables (recent wheezing and medical diagnosis of asthma) and demographic, socioeconomic, environmental, maternal and nutritional variables was obtained by interviewing children's mothers or guardians. Infections with intestinal parasites and antibodies to the zoonotic nematode Toxocara were diagnosed using standard laboratory techniques. Multiple unconditional logistic regression models were used to describe associations between independent variables and outcomes. The prevalence of recent wheezing (one or more reported episodes in the past 12 months) was 42.6%, but only 19.8% of wheezing children were also reported to have a medical diagnosis of asthma (prevalence, 8.5%); 21.5% of the children examined had antibodies to Toxocara. Increased risk of asthma was independently associated with early introduction of bottle feeding, defined as <4 months of exclusive breastfeeding [adjusted odds ratio (aOR) = 2.21, 95% confidence interval (95% CI), 1.07-4.59, P = 0.033], and seropositivity to Toxocara (aOR = 2.37, 95% CI 1.17-4.77, P = 0.016), suggesting two potential targets for public health interventions.     

Time trend for the prevalence of asthma among school children in a Swedish district in 1985-2005.

AIM: To assess the temporal trend for asthma and asthma-like symptoms over a period of 20 years. METHOD: Repeated cross-sectional surveys with identical study design were carried out among all school children (7-16 years) in a well-defined area in Sweden in 1985, 1995 and 2005. RESULTS: In 2005, the parents of 1110 out of 7825 children (14.2%) answered yes to a screening question on asthmatic symptoms. Of these, 783 out of 1110 (70.5%) replied to a postal questionnaire with detailed questions concerning symptoms and asthma management. The rate of affirmative response to the screening question was unchanged between 1995 and 2005. However, the percentage of children with wheezing or three or more asthma-like symptoms decreased, whereas the percentage of children with physician-diagnosed asthma increased steadily since 1985. The number of reported symptoms was closely associated with the number of days with physical restriction. The annual sale of inhaled steroids from local pharmacies was stable between 1995 and 2005. CONCLUSION: The increase in asthmatic symptoms in school children has peaked. Reduced severity of symptoms and divergent trends for wheezing and physician-diagnosed asthma suggest an increased awareness of asthma with improved management of the symptoms. However, differences in trends between allergic and nonallergic asthma could not be excluded.     

儿童血清过敏原与哮喘发生关系的探讨

目的探讨儿童血清特异性Ig E(s Ig E)过敏原与哮喘发生的关系。方法采用免疫印迹法对2004年12月至2013年4月就诊的2 239例1~14岁单纯哮喘患儿(n=1 415)和非过敏性疾病患儿(n=824)的血清s Ig E过敏原进行检测,分别建立所有样本、不同年龄及不同性别单纯哮喘与非过敏性疾病的病例对照模型,采用多因素logistic回归分析探讨过敏原与哮喘发生的关系。结果 2 239例患儿中,血清s Ig E阳性者1 028例(45.91%),过敏原阳性率居于前三位的为户尘螨(15.68%)、屋尘(14.29%)和霉菌类(13.40%)。病例对照研究结果显示,户尘螨、霉菌类、屋尘、腰果/花生/黄豆是哮喘发病的危险因素(P0.05);不同年龄组与哮喘发生相关的过敏原有所不同,1岁~组儿童仅屋尘与哮喘的发生有关,户尘螨和屋尘是3~14岁儿童哮喘发生的危险因素,而霉菌类是6~14岁儿童哮喘发生的危险因素(P0.05);户尘螨和屋尘是男、女儿童哮喘发生的危险因素(P0.05),而腰果/花生/黄豆和霉菌类仅是男性儿童哮喘发生的危险因素(P0.05)。结论户尘螨、屋尘、霉菌类为哮喘患儿最常见过敏原,且与哮喘发生关系极为密切。     

High body mass index, asthma and allergy in Swedish schoolchildren participating in the International Study of Asthma and Allergies in Childhood: Phase II

AIM: To assess the relationship between high body mass index (BMI) and asthma and atopic manifestations in 12-y-old children. METHODS: The relationship between high BMI and asthma symptoms was studied in 457 sixth-grade children, with (n = 161) and without (n = 296) current wheeze. High BMI was defined as > or = 75th percentile of gender-specific BMI reference values for Swedish children at 12 y of age; overweight as a subgroup of high BMI was defined as > or = 95th percentile. Children with a BMI < 75th percentile served as controls. Questionnaires were used to assess asthmatic and allergic symptoms, and bronchial hyperresponsiveness was assessed by hypertonic saline provocation tests. RESULTS: Current wheeze was associated with high BMI after adjustment for confounding factors (adjusted OR 1.7, 95% CI 1.0-2.5) and overweight had an even more pronounced effect (adjusted OR 1.9, 95% CI 1.0-3.6). In addition, asthma severity was associated with high BMI, as evaluated by the number of wheezing episodes during the previous 12 mo among the wheezing children (adjusted OR 2.0, 95% CI 1.0-4.0). There was also an association between high BMI and the presence of eczema in wheezing children (adjusted OR 2.2, 95% CI 1.0-4.6). However, high BMI was not significantly associated with hay fever, positive skin prick tests or bronchial hyperresponsiveness. CONCLUSION: The study confirms and extends a previously observed relationship between BMI and the presence of wheezing and asthma.     

Under-recognition of childhood asthma in Singapore: evidence from a questionnaire survey

In a recent study on the prevalence of childhood asthma and allergies using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires, 6238 Singapore school children in two age-groups, 6-7 years (n = 2030) and 12-15 years (n = 4208), were evaluated. Of the 1856 children who reported asthma-like symptoms (wheezing, exercise-wheezing, persistent nocturnal cough), 919 (49%) had not been diagnosed asthmatic. Of these undiagnosed children, 731 (39%) reported current symptoms of asthma. Under-recognition of asthma was more prevalent among those with persistent nocturnal cough and mild symptoms. In addition, the discordance between wheezing in the last 12 months and a diagnosis of asthma was significantly higher among the younger age-group (6-7 years), but exercise-induced wheezing was less recognized as a symptom of asthma among the older age-group (12-15 years). This study has shown that there is a substantial degree of under-recognition of asthma among school children in Singapore.     

Hypertonic saline challenge tests in the diagnosis of bronchial hyperresponsiveness and asthma in children

The hypertonic saline challenge test is the recommended method to assess bronchial hyperresponsiveness in the International Study of Asthma and Allergies in Childhood (ISAAC). The sensitivity of this procedure to assess asthma symptoms, however, has been reported to vary among study centers. The purpose of our study was to evaluate the value of this provocation test in an epidemiological survey in children, and to relate the degree of bronchial hyperresponsiveness to the severity of asthma symptoms. All 11–13‐year‐old children from 16 randomly selected schools in Linköping, Sweden received a questionnaire regarding respiratory symptoms and allergic disease. Skin prick tests with eight inhalant allergens were performed. In addition, all children with wheeze over the past 12 months (current wheeze) and a random sample of children without current wheeze were invited to perform hypertonic saline provocation tests. A complete data set was available for 170 children, including 50 with and 120 without current wheeze. Bronchial hyperresponsiveness (BHR) was defined as at least 15% decline in FEV₁. The degree of BHR was represented by the response/dose ratio, i.e. the fall in FEV₁ divided by total dose of inhaled saline. The severity of asthma symptoms was classified by the number of wheezing episodes over the past 12 months. ‘Asthma ever’ was defined by a combination of symptoms in the questionnaires. Children with ‘asthma ever’ and current wheeze were considered as having current asthma. Current atopic asthma was defined as current asthma with at least one positive skin prick test. The sensitivity of the procedure to detect ‘asthma ever’, current asthma and current atopic asthma was 62, 61 and 83%, and the specificity 83, 81 and 60%, respectively. The positive challenge rate was 52, 34, 13 and 7% among current wheezers, previous wheezers, non‐wheezers with a history of allergy and healthy children. The degree of bronchial hyperresponsiveness increased with the number of wheezing episodes. Thus, the median and range of the response/dose ratio were 4.8%/ml (2.1–14.8), 2.6%/ml (0.7–8.6) and 1.3%/ml (0.8–2.7), respectively, for children with ≥ 4 episodes, 1–3 episodes and no wheezing episodes over the past 12 months (p<0.001). In conclusion, hypertonic saline provocation test is useful as a tool to detect asthma in epidemiological studies in children. The degree of bronchial hyperresponsiveness, as represented by the response/dose ratio, reflects the severity of asthma symptoms.     

呼出气一氧化氮联合体外过敏原检测对识别反复喘息患儿中哮喘高危患儿的意义

目的探讨体外过敏原、呼出气一氧化氮(FeNO)联合检测对识别反复喘息患儿中哮喘高危患儿的临床价值。方法选取反复喘息患儿148例(0.5~6岁)为研究对象,80例门诊健康体检儿童为对照组。采用Pharmacia UniCAP免疫检测分析仪测定特异性免疫球蛋白(sIgE),纳库仑一氧化氮分析仪检测FeNO,并评估哮喘预测指数(API)。结果 148例反复喘息患儿中,sIgE阳性102例,阳性率为68.9%,明显高于对照组(11.3%,9/80)(P0.05)。喘息组患儿FeNO检测值及阳性率均明显高于对照组(P0.05)。喘息患儿的API总阳性率为32.4%,而API阳性患儿FeNO检测值为51±6 ppb,明显高于API阴性患儿(13±5 ppb)(P0.05)。sIgE阳性患儿中API阳性检出率为40.2%(41/102),FeNO阳性患儿中API阳性检出率为50.1%(38/73),二者阳性率比较差异无统计学意义。sIgE阳性+FeNO阳性组患儿中API阳性检出率为81.4%,明显高于sIgE、FeNO二者单独阳性组(P0.05)。结论 FeNO、体外过敏原联合检测对反复喘息患儿中哮喘高危患儿的检出率明显优于二者单独检测,二者联合检测为儿童哮喘的早期识别诊断、干预提供了良好的手段。     

Prevalence of respiratory symptoms among 7 and 11 year old schoolchildren and association with asthma.

A new self administered questionnaire completed by parents was used to study the prevalences of wheeze, shortness of breath, and cough in 2503 Southampton schoolchildren aged 7 and 11 together with exacerbating factors and background information including treatment and diagnosis. The questionnaire had a response rate of 84% and was found to be highly repeatable with respect to current symptoms. The overall prevalences of wheeze and shortness of breath in the current year (1986) were 12.1% and 8.5% respectively. Social class, home ownership, parental smoking, and presence of a family pet were unrelated to symptom prevalence. According to the parents the overall diagnosis rate for asthma was 9.5%. In common with other studies, however, we found considerable evidence for undertreatment. The symptoms of wheeze and nocturnal and morning breathlessness occurred more commonly in boys, but this sex ratio decreased with increasing age. The prevalences of wheeze and shortness of breath were similar in the two age groups. In contrast, there were only small differences between the sexes with respect to cough whereas, among children without wheeze or shortness of breath, there was a fall in the prevalence of cough from 18.9% at 7 years to 8.7% at 11 years. When controlling for the other respiratory symptoms, wheeze was the only symptom significantly related to parental asthma. The fall in the prevalence of cough between the two age groups is unlikely to be related to changes in asthma prevalence and, when not associated with wheeze, may be an indicator of separate pathology.     

Variability in Diagnosed Asthma in Young Children in a Large Pediatric Primary Care Network

ObjectiveOur objectives were to 1) quantify the frequency of wheezing episodes and asthma diagnosis in young children in a large pediatric primary care network and 2) assess the variability in practice-level asthma diagnosis, accounting for common asthma risk factors and comorbidities. We hypothesized that significant variability in practice-level asthma diagnosis rates would remain after adjusting for associated predictors.MethodsWe generated a retrospective longitudinal birth cohort of children who visited 1 of 31 pediatric primary care practices within the first 6 months of life from 1/2005 to 12/2016. Children were observed for up to 8 years or until the end of the observation window. We used multivariable discrete time survival models to evaluate predictors of asthma diagnosis by 3-month age intervals. We compared unadjusted and adjusted proportions of children diagnosed with asthma by practice.ResultsOf the 161,502 children in the cohort, 34,578 children (21%) received at least 1 asthma diagnosis. In multivariable modeling, male gender, minority race/ethnicity, gestational age <34 weeks, allergic rhinitis, food allergy, and prior wheezing episodes were associated with asthma diagnosis. After adjusting for variation in these predictors across practices, the cumulative incidence of asthma diagnosis by practice by age 6 years ranged from 11% to 47% (interquartile range: 24%–29%).ConclusionsAcross pediatric primary care practices, adjusted incidence of asthma diagnosis by age 6 years ranged widely, though variation gauged by the interquartile range was more modest. Potential sources of practice-level variation, such as differing diagnosis thresholds and labeling of different wheezing phenotypes as “asthma,” should be further investigated.     

Under diagnosis of asthma in school children and its related factors

A cross-sectional study was carried out on one thousand school children studying in three public schools of Delhi and Haryana between 10 to 17 year age group over the period of one year (2001-02). It aimed in studying under diagnosis of asthma in school children and its related factors. Questionnaires including details of medical, social, environmental factors precipitating asthma were filled by the parents and class teachers. Pulmonary function test (PFT) was performed. Based on questionnaires and PFT results, children were grouped as labeled and unlabeled asthmatics. Cough was found to be equally prevalent in both the groups while wheezing and shortness of breath were independent and significant factors associated with getting a physician diagnosis.