Association of Indoor Allergens and Mold with Asthma Development in Children

Abstract

WM1-O-04 Introduction: Exposure to indoor allergens has been associated with increased symptoms among asthmatic children. Exposure in the first year of life to indoor allergens might also be associated with the development of asthma. We enrolled a cohort of infants with an asthmatic sibling to investigate this association. Methods: A cohort of 695 children at risk for asthma was enrolled at birth and followed until age 6. Mothers were visited in their homes (age 2–3 months) to obtain baseline information and collect samples to measure indoor allergens (Der p, Der f, Can f, Fel d) and mold (total mold count, Cladosporium count, Penicillium count). Follow-up interviews were conducted quarterly to age 3 and annually to age 6 to determine asthma symptoms, use of asthma medication, and physician diagnosis of asthma, and to update information on observed mold, pet ownership, and smoking in the home. Logistic regression models were used to assess the relationship of early exposure to indoor allergens and mold with 2 outcomes: asthma symptoms at age 6 (wheeze, persistent cough, chest tightness, and shortness of breath); and physician diagnosed asthma with symptoms or medication use at age 6. Results: At age 6, 258 children had asthma symptoms, 206 were using asthma medication, and 166 had physician diagnosed asthma with current symptoms. Controlling for child's gender, ethnicity, mother's education, parental history of asthma, and smoking in the home, early exposure to measured allergens was not associated with asthma symptoms or asthma diagnosis at age 6. Mother's report of observed mold at the home interview was associated with asthma diagnosis at age 6 (odds ratio [OR] = 1.80; 95% CI, 1.17–2.76) Asthma symptoms at age 6 were associated with both reported mold at the home interview (OR = 1.60; CI, 1.13–2.26) and reported mold at age 5 (OR = 1.70; CI, 1.09–2.64). Substituting measured mold counts at the home interview for reported mold in the analysis, neither total mold count nor Cladosporium count was associated with increased risk of asthma diagnosis or symptoms. However, increasing levels of Penicillium (1–499 CFU/m3, 500–999 CFU/m3, ≥1000 CFU/m3) measured at the home interview were associated with increasing risk of asthma symptoms at age 6 (OR = 1.13; CI, 0.78–1.64; OR = 2.28; CI, 0.79–6.61; OR = 2.71; CI, 1.04–7.08). Conclusion: Exposure to mold, especially Penicillium early in life may be associated with increased risk of asthma development by age 6.