Persistence of atopic effects on airway calibre and bronchial responsiveness in older adults.

BACKGROUND the relationships between atopy and chronic airflow obstruction and bronchial hyperresponsiveness in adults are unclear. We measured airways calibre (FEV1), bronchial responsiveness, eosinophil count and total serum IgE in a random population sample of adults aged 45 years or older. METHODS Caucasian adults (n = 783) were selected from the practice lists of local general practitioners using random number tables. Responders to a postal questionnaire were invited to attend for venous blood sampling and methacholine challenge (Newcastle dosimeter method). FINDINGS the questionnaire response rate was 92.3% (723 subjects); 62.5% of subjects invited to attend did so. Attenders were slightly younger than the whole study population, but otherwise representative. Methacholine challenge was completed by 208 subjects. Geometric mean IgE level was higher in current smokers; both IgE and eosinophils were raised in subjects reporting asthma. Multiple regression showed a negative independent relationship between age- and sex-standardized eosinophils and baseline FEV1 and a positive relationship between standardized IgE score and level of bronchial responsiveness. Separate analysis of subjects aged <65 and > or =65 years showed that these relationships were only significant in older subjects. INTERPRETATION airways calibre and level of bronchial responsiveness are associated with measures of atopy in older adults. Atopy should not be overlooked as a factor in elderly patients with asthma or chronic airflow obstruction.