Increased prevalence of asthma and allied diseases among active adolescent tobacco smokers after controlling for passive smoking exposure. A cause for concern?

Background Whereas effects on allergic and respiratory health have been established for passive tobacco smoking, contradictory results still exist for active tobacco smoking. Objective Whether adolescents with asthma and allied diseases have higher rates of active smoking compared with adolescents without asthma was assessed after controlling for environmental tobacco smoking exposure. Methods A population-based sample of 14578 adolescents was enrolled in an epidemiological survey on allergies in France. Results After controlling for age, sex, geographic region, familial allergy and passive smoking, current (in the past year) wheezing (12.4%), current asthma (5.6%), lifetime asthma (12.3%), current rhinoconjunctivitis (13.9%), lifetime hayfever (14.4%) and current eczema (9.3%) but not lifetime eczema (22.5%) were all significantly related to active smoking (>1 cigarette/day) (9.3%). A higher risk of current wheezing, current and lifetime asthma or current eczema was seen in smokers exposed to passive smoking compared with smokers not exposed to it using a polychotomous logistic regression model, in which the different modalities of exposure to active and passive smoking constituted the response variable. Passive smoking was significantly associated only with current diseases. Active smoking was also highly related to both severe asthma (OR = 4.02; 95% confidence interval: 1.37, 11.79) and severe rhinoconjunctivitis (OR = 2.95; 1.58, 5.49). The highest rate of adolescents suffering from the co-morbidity of lifetime asthma and hayfever (3.6%) was also seen in active smokers compared with passive and non-smokers (5.5% vs. 3.6% and 3.1%, respectively; P = 0.001). Conclusions Being asthmatic or allergic does not seem to act as a deterrent towards starting active smoking or continuing to smoke in adolescence. Results suggest the need for considering individual allergic status in programming health educational activities aimed at reducing smoking among adolescents.