DO DAIRY-PRODUCTS INDUCE BRONCHOCONSTRICTION IN ADULTS WITH ASTHMA

Citation
Rk. Woods et al., DO DAIRY-PRODUCTS INDUCE BRONCHOCONSTRICTION IN ADULTS WITH ASTHMA, Journal of allergy and clinical immunology, 101(1), 1998, pp. 45-50
Citations number
25
Categorie Soggetti
Immunology,Allergy
ISSN journal
00916749
Volume
101
Issue
1
Year of publication
1998
Part
1
Pages
45 - 50
Database
ISI
SICI code
0091-6749(1998)101:1<45:DDIBIA>2.0.ZU;2-O
Abstract
Background: Dairy products have often been implicated as a cause of ex acerbation of asthma, but there is little scientific evidence to suppo rt this hypothesis. Objective: We sought to determine whether dairy pr oducts induce bronchoconstriction in a group of adults with asthma. Me thods: Twenty subjects with asthma (13 women and 7 men) were recruited from respondents who had previously completed a food and asthma quest ionnaire. Ten subjects perceived that their asthma became worse with i ngestion of dairy products (positive perceivers), whereas ten were neg ative perceivers. None of the subjects had positive skin prick test re sults with cow's milk The study was a randomized, cross-over, double-b lind, placebo-controlled trial. Subjects complied with a dairy-free di et throughout the study. The active challenge was a single-dose drink equivalent to 300 ml of cow's milk. A positive reaction was defined as a 15% reduction in both FEV1 and peak expiratory dow (PEF) on the act ive challenge day compared with results obtained at the same time on t he placebo day. Results: For both FEV1 and PEF there were no statistic ally significantly differences in group means between active challenge and placebo challenge, between sequence of administration, or between perceptions. Nine subjects showed FEV1 or PEF changes that were great er than 15% of baseline values: four patients shelved changes after bo th active and placebo treatment; two after treatment with placebo only ; and three after active treatment alone. Of the latter group, two sub jects showed changes only in PEF, and when one of these subjects under went a further detailed study, no asthmatic reaction could be demonstr ated. Conclusion: It is unlikely that dairy products have a specific b ronchoconstrictor effect in most patients with asthma, regardless of t heir perception.