The association of smoking with sensitization to common environmental allergens: Results from the European Community Respiratory Health Survey

Background: Smoking is a risk factor for sensitization to some occupational allergens, but its association with sensitization to common environmental allergens remains unclear, Objective: We sought to determine the association of smoking with total IgE levels and with sensitization to 3 common environmental allergens in data from the European Community Respiratory Health Survey Methods: A detailed smoking history and blood sample far determination of s erum total IgE and specific IgE levels to house dust mite, grass, and cat a llergens was obtained from 13,002 randomly selected young adults Living in the areas served by 34 centers in 14 countries. Associations with smoking s tatus and amount smoked sere determined. Because there was evidence of hete rogeneity between centers in the association of age, sex, and smoking with sensitization, odds ratios (ORs) were determined for each center and combin ed by using random-effects meta-analysis. Results: Compared with lifetime nonsmokers, current smokers were at an incr eased risk of sensitization to house dust mite allergen (OR, 1.13; 95% conf idence interval [CI], 1.02-1.26) but a decreased risk of sensitization to g rass (OR, 0.76; 95% CI, 0.67-0.88) and cat allergens (OR, 0.69; 95% CI, 0.5 9-0.80), Exclusion of those with symptoms suggestive of current asthma stre ngthened the association of smoking with sensitization to house dust mite a llergen (OR, 1.29; 95% CI, 1.11-1.50). The geometric mean total IgE level w as higher in smokers and was higher among those who currently smoked the mo st compared with those who smoked less than 5 cigarettes per day, Conclusion: The association between smoking and sensitization to common env ironmental allergens is different For different allergens.