Adherence to all asthma treatments was assessed by means of study interviews, corroborated by study physicians, and encouraged by asthma counselors every 3 months. Allergen skin testing consisted of a panel of 14 extracts: mouse and rat epithelia, dog epithelium, dust mites (Dermatophagoides farinae and D. pteronyssinus), cat hair, an American–German cockroach mix, German cockroach, molds (Penicillium notatum, aspergillus species, Alternaria tenuis, and Cladosporium herbarum), timothy grass, and a ragweed mix (Greer Laboratories). A positive test was defined as a wheal that was larger than the negative control by 3 mm or more.
Total serum levels of IgE and allergen-specific IgE levels for dust mites, German cockroach, and A. tenuis were measured. Dust from the participant’s bed and bedroom floor was collected with the use of a validated self-collection procedure12 (link) and assayed for dust mite (Der p 1 and Der f 1), German cockroach (Bla g 1), cat (Fel d 1), dog (Can f 1), and mouse (Mus m 1).
Nasal-secretion samples were collected and frozen at four of the eight research sites at week 48 and within 7 days after the onset of an asthma exacerbation. Total RNA was extracted and analyzed by means of multiplex reverse-transcriptase–polymerase-chain-reaction assay13 (link),14 (link) with the use of primers and probes specific for rhinoviruses, influenza virus, parainfluenza virus, coronavirus, respiratory syncytial virus, meta-pneumovirus, enterovirus, adenovirus, and boca-virus.
Total serum levels of IgE and allergen-specific IgE levels for dust mites, German cockroach, and A. tenuis were measured. Dust from the participant’s bed and bedroom floor was collected with the use of a validated self-collection procedure12 (link) and assayed for dust mite (Der p 1 and Der f 1), German cockroach (Bla g 1), cat (Fel d 1), dog (Can f 1), and mouse (Mus m 1).
Nasal-secretion samples were collected and frozen at four of the eight research sites at week 48 and within 7 days after the onset of an asthma exacerbation. Total RNA was extracted and analyzed by means of multiplex reverse-transcriptase–polymerase-chain-reaction assay13 (link),14 (link) with the use of primers and probes specific for rhinoviruses, influenza virus, parainfluenza virus, coronavirus, respiratory syncytial virus, meta-pneumovirus, enterovirus, adenovirus, and boca-virus.
