Role of Gender and Hormone-related Events on IgE, Atopy, and Eosinophils in the Epidemiological Study on the Genetics and Environment of Asthma, Bronchial Hyperresponsiveness and Atopy

Background: The pattern of asthma over the lifespan is different in male and female patients, but etiologic differences according to gender are only partially understood. In women, information regarding factors explaining perimenstrual asthma and the role of hormone-related aspects on asthma-related phenotypes is scanty.

Objective: To assess the relationships of eosinophils, IgE, and atopy with (1) asthma according to gender and age of onset and (2) hormone-related events.

Methods: Using data from the Epidemiological study on the Genetics and Environment of Asthma, Bronchial Hyperresponsiveness and Atopy, adults and children with asthma recruited in chest clinics (n=313) and first-degree relatives of patients with asthma (n=214) were compared with nonasthmatic controls (n=334) and first-degree relatives without asthma (n=595).

Results: Among asthmatic women, eosinophilia was significantly associated with perimenstrual asthma independently from age, smoking, and asthma severity (eosinophils/mm(3) 330 vs 194; P=.01). In nonasthmatic women, IgE level was significantly decreased (by half) and atopy decreased with menopause, and IgE increased with oral contraceptive use, independently from age and smoking. Considering both genders, the increase of eosinophil counts with asthma was significantly greater in women with childhood-onset asthma than in women with adulthood-onset or in men in general. No interaction between gender and asthma was observed for eosinophils in children and for IgE level and atopy in children and adults.

Conclusion: Results suggest a role of hormone-related events on asthma-related traits and support the hypothesis of the role of eosinophils in the persistence and severity of asthma.