Allergen Sensitivity and Asthma Severity at an Inner City Asthma Center

Abstract

The objective of this study was to examine the relationship of allergen sensitivity to asthma symptoms among inner-city asthmatics seen at our Brooklyn, NY, asthma center. We hypothesized that asthma severity would increase for adults and children with increased cockroach and dust mite allergen sensitivity. Data were gathered from retrospective chart review for all patients who were treated at the center with a diagnosis of asthma and had undergone skin-prick testing (SPT) for allergen sensitivity during 1998 (pediatric, n = 79; adult, n = 29). Asthma severity (determined by National Heart, Lung and Blood Institute [NHLBI] asthma severity class) was examined in relation to allergen sensitivity. Allergen sensitivity was measured by percent positive to skin-prick testing as well as by relative mean diameter of skin prick test wheals. For adults, mite sensitivity prevalence was 61% and cockroach sensitivity prevalence was 41%. For children, mite sensitivity prevalence was 49%; cockroach sensitivity prevalence was 42%. For adults, asthma severity correlated significantly with sensitivity to Cladosporium, tree, and grass as measured by percent positive skin tests and by increasing mean diameter of skin test wheals. There was a significant correlation with severity for adult dust mite sensitivity only as measured by increasing mean wheal diameter. Ragweed sensitivity showed a significant correlation with severity only as measured by percent positive skin tests. There was a significant positive association for adults between increasing asthma severity and total number of allergen sensitivities per subject. There was no significant correlation for children between asthma severity and total number of allergen sensitivities per subject. Among children, no specific allergen sensitization showed a significant positive association with asthma severity. By both measures of allergen sensitization, there was a significant negative association for children between Cladosporium and asthma severity. Among our inner-city asthmatic population significant correlation between mite sensitivity and asthma severity was found only in adults. No significant association was seen with cockroach. However, outdoor allergen sensitivity (Cladosporidium, tree, ragweed, and grass) significantly correlated with asthma for adults in this inner city population.

Sensitization to Common Allergens in Adults with Asthma

“…The investigations that have been reported were at single sites and tended to have small sample sizes. 5,6,9 In a study of patients being evaluated by radioallergosorbent testing in New York City, asthmatics were more likely than non-asthmatics to be hypersensitized to cat dander or dust mites (D. farinae) and to Deuteromycetes molds (Alternaria tenuis, Aspergillus fumigatus, and Cladosporium herbarum), whereas pollen (tree, grass, ragweed) hypersensitivity was not independently associated with asthma. 9 Although cat dander was excluded from another New York City study of allergic sensitization, 6 most (83%) of the 29 adults with asthma had a positive skin prick test to at least one of 7 common allergens or allergen mixtures: ragweed, grasses, dust mite (Dermatophagoides pteronyssinus and D. farinae), and trees.…”

“…9 Although cat dander was excluded from another New York City study of allergic sensitization, 6 most (83%) of the 29 adults with asthma had a positive skin prick test to at least one of 7 common allergens or allergen mixtures: ragweed, grasses, dust mite (Dermatophagoides pteronyssinus and D. farinae), and trees. 6 At the Portland, OR, site in the European Community respiratory health survey (ECRHS) studies, 74% of the 39 participants with asthma were sensitized to at least one of 9 common allergens, the most frequent sensitizations being to timothy grass, D. pteronyssinus, birch, A. alternata, and cat. 5 Thus, studies in the United States have consistently observed a high prevalence of atopy among adult asthmatics, with the distribution of specific allergen sensitivities varying between sites.…”

“…Updated National Asthma Education and Prevention Program (NAEPP) guidelines recommend allergy testing for persons with persistent asthma and, after sensitivity is determined, avoidance of the trigger and allergen abatement. 8 Few studies done in the United States, however, have provided information about atopy and adult asthma 5,6,9 or investigated the extent to which measurement of atopy might influence medical decisions. Because more than 4 million visits per year by asthma patients are to family practitioners and other generalists, 10 awareness of the prevalence of atopy among asthma patients may help to improve asthma patient management by these physicians.…”

“…3,4 Evidence suggests that sensitization to common allergens, including molds and dust mites, correlates with greater asthma severity. [5][6][7] Knowledge of sensitivity to specific allergens is an important guide to asthma management, through allergen avoidance, immunotherapy, and pharmacological treatment of allergies. Updated National Asthma Education and Prevention Program (NAEPP) guidelines recommend allergy testing for persons with persistent asthma and, after sensitivity is determined, avoidance of the trigger and allergen abatement.…”

Sensitization to indoor allergens and frequency of asthma exacerbations in children

“…Few studies have focused on the most common indoor allergens in children living in tropical climates, which contributes to respiratory infections as they are suspected triggers of asthma exacerbations. 5,9,[11][12][13][14] Therefore, we conducted a study to examine the correlation between sensitization to common indoor allergens and the frequency of asthma exacerbations. We also investigated the correlation between mean wheal diameters of each allergen and the frequency of asthma exacerbations.…”