Dutch workers have proposed that people with asthma and those smokers who develop chronic airflow obstruction share a common allergic constitution. To study whether smoking itself is associated with indicators of allergy, we have examined 237 men aged [51][52][53][54][55][56][57][58][59][60][61] years (120 smokers, 73 ex-smokers, and 44 non-smokers) who were recruited to a long term study of lung function in 1974, at which time men with a clinical diagnosis of asthma were excluded. Smokers, ex-smokers, and non-smokers did not differ in personal or family history of allergic disease, but the prevalence of positive responses to skinprick tests was greater in exsmokers (59%) than in the other two groups (33% and 34%). In men with negative responses to skinprick tests total serum IgE was greater in smokers (log,0 mean 1-41 IU/ml) and in ex-smokers (log10 mean 1-53 IU/ml) than in non-smokers (log10 mean 1 12 IU/ml). In men with positive skin test responses serum IgE was similar in the three groups (log10 mean ranging from 1-68 to 1-78 IU/ml). Geometric mean total white cell counts in the peripheral blood were higher in smokers (7.34 x 109/l) than in non-smokers (5.82 x 109/l); the value in ex-smokers (6-16 x 109/l) was intermediate. Absolute blood eosinophil counts were increased in smokers disproportionately to the increase in total white cell count. Thus smoking is associated with small increases in some markers of allergy. These changes are probably acquired after the onset of smoking but sequential studies are required to amplify these cross sectional observations. Smokers whose skin test responses are positive appear more likely to give up smoking.In 1960 Dutch workers' proposed that individuals with asthma and smokers with chronic and mainly irreversible airflow obstruction shared a common allergic constitution and increased non-specific bronchial reactivity. It was not clear whether the increased reactivity followed or preceded the development of airway narrowing.2 In an earlier study from this department Fletcher and coworkers3 found little evidence that allergy contributed to the development of chronic airflow obstruction in smokers; more recently we re-examined some of the younger men in this original study, and in contrast found that the rate of decline of lung function was more rapid in smokers who had some evidence of an allergic constitution than in those who did not.4 Furthermore, a series of reports from Tucson5-7 has investigated the interrelations between atopy, Address for reprint requests: Dr NB Pride, Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London W12 OHS.
Accepted 8 October 1984eosinophilia, and airflow obstruction and found that blood eosinophilia was associated with impairment of ventilatory function regardless of smoking habit. Smokers have also been shown to have a higher total serum immunoglobulin E (IgE) level than nonsmokers-'4 and a raised white cell count in the peripheral blood. '5-23 These findings have renewed interest in the Dutc...