Mouse Allergen Exposure, Wheeze, and Atopy in the First Seven Years of Life

S214 Abstracts

Asthma and Allergies in Preschool Children: Prevalence and Risk Factors G. W. K. Wong, T. F. Leung, E. K. H. Liu, T. F. Fok; Pediatrics, Chinese University of Hong Kong, Hong Kong SAR, CHINA. RATIONALE: The prevalence of asthma and related allergic disorders has increased in many countries over the past few decades. Epidemiology data in preschool children is limited. This study was designed to determine the prevalence of, and risk factors for asthma in preschool Chinese children from Hong Kong. METHODS: Parents of children aged 2-6 years living in Hong Kong were surveyed by a modified ISAAC questionnaire to ascertain the presence of symptoms of asthma and related atopic conditions and various possible risk factors. RESULTS: A total of 3089 subjects (1506 boys) were studied. The prevalence of wheeze ever and current wheeze were 16.7% and 9.3%. The prevalence of symptoms of rhinoconjunctivitis and flexural eczema within the past 12 months were 11.8% and 5.6%. A total of 234 subjects were born in mainland China and migrated to Hong Kong subsequently. Their median age of migration was 2.7 years. When compared with children born and raised in Hong Kong, they have significantly lower prevalence of current wheeze (3.4% vs. 9.6%, P <0.01) and other allergic symptoms. Multiple logistic regression analyses with adjustment of gender and place of birth revealed 3 environmental factors in the first year of life were associated with wheezing attacks within the past year. They were the use of foam pillow (OR: 1.54; 95%CI: 1.05-2.24), the use of gas as cooking fuel (1.87; 1.17-2.98), and the presence of damp spots, visible moulds or fungus on walls or ceiling (1.43; 1.06-1.96). CONCLUSIONS: Early environmental exposures are important determinants of subsequent development of asthma symptoms in the preschool years. Funding: Research Grant Council of Hong Kong CUHK4165/02M

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The Positive Relationship of Atopy to Obesity in Women is Negatively Correlated to Serum Leptin M. R. Windt1,2, A. R. Tagliaferro3, V. J. Vieira1, A. M. Ronan1; 1Department of Animal & Nutritional Sciences, University of New Hampshire, Durham, NH, 2Center for Asthma Allergy and Respiratory Disease, North Hampton, NH, 3Department of Animal &Nutritional Sciences, University of New Hampshire, Durham, NH. RATIONALE: Epidemiological studies have found BMI to be a positive independent correlate of asthma and atopy in women. We investigated the relationship in asthmatic and non-asthmatic obese(OB) and nonobese(NO) women to atopy, fat mass(FM), insulin resistance(IR), plasma concentrations of 17 beta-estradiol(E), IL-4, and leptin. METHODS: Asthma was diagnosed by history and >20% reduction in FEV1 to methacholine challenge or >12% increase in FEV1 to brochodialator. Atopy was established by a positive serum Phadiatop(Pharmacia Upjohn). FM was measured by air displacement plethsmography(Bod Pod). Blood was obtained for measurements of: glucose, insulin,C-peptide, E, sex hormone binding globulin(SHBG), IL-4, and leptin. Insulin resistance was determined by fasting insulin resistance index(FIRI), and by oral glucose tolerance test. RESULTS: Insulin levels were higher among asthmatic(A) than nonasthmatic(NA) women independent of weight C-peptide was greater among A and OB than respective controls. Atopy was greater among A vs NA(p<0.01). Specific IgE was almost 3 times higher among OB than NO(p=0.008). FM was a positive predictor of atopy(p=0.01). Plasma concentration of leptin correlated closely to fat mass( p<0.0001) but there was a negative correlation to specific IgE(p=0.01). CONCLUSIONS: Findings confirm a direct relationship between obe sity and a Th2 immune response in women.Leptin had a positive correlation with obesity, but a negative correlation to atopy. Leptin therefor may have a regulatory role in atopy. Funding: ALANH, GSK, Scheering-Plough

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J ALLERGY CLIN IMMUNOL FEBRUARY 2006

Demographic and Clinical Characteristics of Children and Adolescents with Severe or Difficult-to-Treat Asthma B. Chipps1, S. J. Szefler2, J. H. Lee3, T. Haselkorn4, D. R. Mink5, Y. Deniz3, F. E. Simons6; 1Capital Allergy and Respiratory Disease Center, Sacramento, CA, 2National Jewish Medical and Research Center, Denver, CO, 3Genentech, Inc., South San Francisco, CA, 4EpiMetrix, Inc., Sunnyvale, CA, 5Ovation Research Group, San Francisco, CA, 6University of Manitoba, Winnipeg, MB, CANADA. RATIONALE: TENOR is an observational study that provides unique insights into severe or difficult-to-treat asthma in children as young as 6 years of age. METHODS: 1,261 patients were stratified by baseline age group (6-8, 911, 12-14, 15-17 years). The chi-square test for categorical variables and ANOVA for continuous variables were used to identify significant differences among age groups, stratified by gender. RESULTS: Most patients had moderate (55%) or severe (41%) asthma by physician assessment. Of those using 3 long-term controllers (62%), in the previous three months 53% of children and 44% of adolescents reported a corticosteroid burst and 25% of children and 19% of adolescents had an emergency department visit. Past intubation was reported by 10% and 15% of children and adolescents, respectively. Medications used were: short-acting beta-agonists 96%, inhaled corticosteroids 95%, longacting beta-agonists 74%, anti-leukotrienes 73%, systemic corticosteroids 15%, anticholinergics 10%, methylxanthines 8%, and cromolyn or nedocromil 9%. In females, weight for age ranged between the 67th-70th percentiles; height for age was between the 42nd-54th percentiles and was different among age groups (p<.01). Loss of lung function with age was seen: pre-bronchodilator FEV1/FVC, males, went from 0.81 (6-8 years) to 0.73 (15-17 years), p<.05; females went from 0.84 (6-8 years) to 0.77 (15-17 years), p<.05. CONCLUSIONS: Children and adolescents in TENOR demonstrated high rates of healthcare utilization and loss of lung function, despite using multiple long-term controllers. Asthma treatments that prevent loss of lung function and reduce healthcare resource use are needed for these patients. Funding: Genentech and Novartis Pharmaceuticals Corp.

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MONDAY

Mouse Allergen Exposure, Wheeze, and Atopy in the First Seven Years of Life W. Phipatanakul1,2, J. C. Celedon3, C. D. Ramsey2, D. L. Sredl4, S. T. Weiss3, D. R. Gold2; 1Pediatric Allergy and Immunology, Children’s Hospital, Boston, Harvard Medical School, Boston, MA, 2Respiratory Epidemiology, Channing Laboratory, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 3Respiratory Epidemiology, Channing Laboratory, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 4Respiratory Epidemiology, Channing Laboratory, Harvard Medical School, Boston, MA. RATIONALE: There are no published studies evaluating the role of early mouse allergen exposure in home environments and the development of wheezing, asthma, and atopy in later life; therefore, our purpose was to examine the relation between mouse allergen exposure in the first year of life and wheezing, atopy, and asthma in the first 7 years of life. METHODS: 440 children in metropolitan Boston with parental history of allergy or asthma in at least 1 parent were followed from birth for 7 years. House dust samples collected at age 2-3 months were analyzed for mouse urinary protein (MUP). Allergy skin testing or specific IgE was obtained at age 7. RESULTS: In multivariate analysis, after adjusting for sex, household income, and other confounders, infants who lived in homes with detectable mouse urinary protein (MUP) in house dust samples collected at age 2-3 months had twice the odds of developing any atopy by age 7 (OR, 2.00; 95% CI, 1.07-3.71; P=0.03). Increased levels of mouse allergen were not associated with an increased risk of developing recurrent wheezing, asthma, allergic rhinitis, or eczema by age 7. Infants with detectable MUP exposure at age 2-3 months also had an increased risk of wheezing in early life, but this effect was not significant by age 7.

828

Abstracts S215

J ALLERGY CLIN IMMUNOL VOLUME 117, NUMBER 2

Household Mouse Allergen Exposure Predicts Asthma Morbidity in Inner-city Pre-School Children E. C. Matsui1, P. A. Eggleston1, J. A. Krishnan2, P. Breysse3, C. Rand2, G. B. Diette2; 1Department of Pediatrics, Johns Hopkins University School Medicine, Baltimore, MD, 2Department of Medicine, Johns Hopkins University School Medicine, Baltimore, MD, 3Department of Environmental Health Sciences, Johns Hopkins University School of Public Health, Baltimore, MD. RATIONALE: Mouse allergen is commonly found in inner-city homes, but there are few data linking it to asthma morbidity. METHODS: Preschool children with asthma (N= 150) were recruited from inner-city Baltimore and underwent allergy skin testing. Bedroom dust samples were collected for analysis of Mus m 1 at baseline, 3, and 6 months. Medication use, symptoms, and health care use were assessed at the same time points. RESULTS: The mean age was 4.4 y, 58% were males, and 92% were African American. 68% were atopic and 17% were sensitized to mouse. All bedrooms had detectable settled dust Mus m 1 (median [IQR]: 2.5 g/g [0.5-8.8]). In longitudinal analyses, mouse-sensitized children exposed to > 0.5 g/g of Mus m 1 were more likely to be hospitalized (OR 4.3; 95% CI 1.0-19.1), visit the emergency department (OR 2.3; 95% CI: 1.1-4.9), and have an unscheduled doctor’s visit (OR 3.9; 95% CI: 1.88.3) for asthma. Exposed and sensitized children were also more likely to report daily beta-agonist use (OR 3.4; 95% CI: 1.6-7.4), more symptom days (IRR 1.8; 95% CI 1.3-2.6), and more nights of symptoms (IRR 1.9; 95% CI: 1.3-2.8) than the others. These findings persisted after adjustment for age, sex, atopy, and cockroach allergen sensitization and exposure. CONCLUSIONS: Among mouse-sensitized children, exposure to higher levels of Mus m 1 predicts poor asthma control and asthma-related health-care utilization. Funding: NIEHS, EPA, NIAID

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Reduction of Endotoxin and Glucan Exposures in The Louisa/Keokuk Environmental Intervention Project (LEIP) for Rural Childhood Asthma P. S. Thorne, E. A. Chrischilles, A. K. W. Kuehl, K. M. Kelly, N. Metwali, L. M. Harris, M. E. O’Neill, A. K. Quella, R. E. Walker; College of Public Health, The University of Iowa, Iowa City, IA. RATIONALE: The LEIP study is a multifaceted in-home environmental intervention designed to reduce exposures of rural children to asthma triggers. Exposures and health outcomes are measured repeatedly over time to determine if exposures are decreased and health status improved. METHODS: Parents of children 6-14 years in 11 rural school districts (n=4618) were sent asthma screening questionnaires and 73.1% (n=3376) returned completed screeners. From these, 299 children were identified as having symptomatic diagnosed asthma. Thus far, 104 have been enrolled in the LEIP study and randomized into extensive or educational intervention groups. Air and surface sampling was performed before and on 3 occasions after home hygiene education and extensive professional cleaning.

830

Health and demographic data were ascertained from baseline questionnaires, asthma diaries, electronic peak flow meters, and bimonthly health questionnaires. RESULTS: Two-thirds of the children had symptoms three or more days during the two-week baseline reporting period. Mean PEF, FEV1, and FEV6 values averaged 60-70% of predicted at enrollment consistent with persistent asthma. These measures improved over time with the intervention. Comparison of airborne endotoxin before and after the first stage of the intervention demonstrated a significant decrease in concentration with the extensive intervention. The percent of homes with lower endotoxin was 80%. Der-p1, Der-f1 and Fel-d1 load in settled dust were decreased an average of 65%, 83% and 89% for the Extensive Intervention group. CONCLUSIONS: Early data from the LEIP study demonstrate that an extensive professional home cleaning intervention can reduce exposures to endotoxin, glucans and allergens with a resulting improvement in asthma symptoms. Funding: NIH R01 ES11392 Sensitization and Asthma Severity in Inner City African Americans (AA) and Latino Americans (LA) in a Large Community Based Cohort R. Kumar1, C. Saltoun2, G. Mosnaim3, L. C. Grammer2, R. DurazoArvizu4, L. Stierman5, J. Shannon6, K. B. Weiss5,7; 1Allergy, Childrens’ Memorial Hospital, Chicago, IL, 2Allergy, Northwestern University, Chicago, IL, 3Allergy, Rush University, Chicago, IL, 4Biostatistics, Loyola University Medical School, Chicago, IL, 5Institute for Healthcare Studies, Northwestern University, Chicago, IL, 6Pulmonary and Critical Care Medicine, John H. Stroger Jr. Hospital of Cook County, Chicago, IL, 7Institute for Healthcare Studies, Hines VA, Chicago, IL. RATIONALE: Little literature on inner-city asthmatic subjects’ patterns of sensitization is from community-based samples. We evaluated sensitization to dust mite and cockroach in a large community-based sample with large numbers of African Americans (AA) and Latinos (LA). METHODS: This is a cross-sectional analysis of sensitization by ethnicity in the Chicago Initiative to Raise Asthma Health Equity cohort, a community-derived asthma cohort of children (aged 8-14, n=398) and unrelated adults (aged 18-43, n=250). Asthma was identified by selfreport and considered active based on current bronchodilator use. Race (self report) and sensitization (ELISA) were determined at baseline. Severity was classified by hospitalization or ED visit in the last year. Analyses compared AA to non-AA and LA to non-LA. RESULTS: For children, AA subjects were more commonly sensitized to roach (OR=1.8, p=0.03). For adults, univariate analysis found LA subjects more commonly sensitized to dust mites (OR=1.9, p<0.05) and AA subjects more commonly sensitized to roach (OR=2.1, p<0.01). These differences were no longer significant when income and household size were included. Secondary multivariate analyses evaluated the correlation of severity to sensitization stratified by ethnicity. Sensitization to dust mite predicted severity only in AA adults (OR=2.7, p<0.009). Roach sensitization was not predictive in any group. CONCLUSIONS: Correlations of ethnicity with patterns of sensitization are modified by SES. The relationship of sensitization and asthma exacerbation is not as prominent in this community-based sample as cohorts recruited in medical settings. This may be due to the fact that this cohort will have less severity and accordingly, less selection bias. Funding: NIH

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MONDAY

CONCLUSIONS: Exposure to mouse allergen in early life is associated with wheezing in early life among children with parental history of atopy. In addition, early mouse allergen exposure is associated with the development of atopy by age 7, independent of other factors. Funding: NIH AI/EHS 35785 and ES 07036. Dr. Phipatanakul is supported by K-23 NIH AI 054972