Sensitization to cat allergen is associated with asthma in older men and predicts new-onset airway hyperresponsiveness. The Normative Aging Study

Am J Respir Crit Care Med. 1997 Jul;156(1):23-7. doi: 10.1164/ajrccm.156.1.9608072.


To explore the relationship between sensitization to inhalant allergens and adult asthma, we performed two nested case-control studies of men being followed in the VA Normative Aging Study. In Study A, 46 subjects (mean age, 61.2 +/- 8.1 yr) with symptoms of asthma and an abnormal methacholine challenge test (cases) were compared with 92 age- and smoking-history-matched subjects, who denied symptoms and had normal methacholine challenge tests (controls). The age of onset of wheezing symptoms for the cases was 49.0 +/- 15.7 yr. Serum IgE reactivity to the aeroallergens Der P 1 and 2, cat, ragweed, and mouse was compared in cases and controls. Cases were more likely to be sensitized to cat allergen (23.9% versus 4.4%, p < 0.001) than were controls. Prevalences of sensitization to Der p 1, Der p 2, ragweed, and mouse were low and similar in the two groups. In Study B, 33 cases who developed new onset airway hyperresponsiveness on methacholine challenge testing were compared with 66 age-matched controls who maintained normal methacholine challenge tests. Cases had a higher prevalence of serum IgE reactivity to cat allergen (18.2% versus 6.1%, p = 0.059) and Der p 2 (21.2% versus 10.6%, p = 0.153) measured in serum obtained 3 yr before the development of airway hyperresponsiveness. These results suggest that in older men, sensitization to cat allergen is associated with asthma and that sensitization predates airway hyperresponsiveness to methacholine.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Allergens / immunology*
  • Animals
  • Asthma / immunology*
  • Bronchial Hyperreactivity / chemically induced
  • Bronchial Hyperreactivity / immunology*
  • Case-Control Studies
  • Cats / immunology*
  • Humans
  • Immunoglobulin E / blood
  • Logistic Models
  • Longitudinal Studies
  • Male
  • Methacholine Chloride
  • Middle Aged


  • Allergens
  • Methacholine Chloride
  • Immunoglobulin E