The effect of cigarette smoking on allergic conditions in Maltese children (ISAAC).

Maltese children are frequently exposed to tobacco smoke through passive and personal smoking. In the phase 3 ISAAC study questionnaire, we enquired about passive smoking to the parents of 3816 (80% response rate) 5- to 8-yr-old children and about passive and personal smoking to 4139 (90% response rate) 13- to 15-yr-old participating children. Thirty-one percent of 5- to 8-yr olds were passive smokers with their father more likely to be the smoker (p < 0.0001). Maternal smoking in the first year of the child's life resulted in the children having an increased chance of wheezing 'ever' (p < 0.001), exercise-induced wheezing (p < 0.05) and being diagnosed with asthma (p < 0.0001). Current smoking by the mother also led to the child having current rhinitis (p < 0.001). Fifty-one percent of 13- to 15-yr olds were passive smokers again with the father more likely to be the smoker (p < 0.0001). Maternal (p < 0.0001) and paternal smoking (p < 0.05) resulted in the children having an increased chance of wheezing sometime in their life, exercise-induced wheezing, nocturnal cough, and being diagnosed with asthma. Current smoking by the mother was more common in children having current rhinitis (p < 0.05), while current smoking by both mother and/or father led to itchy/watery eyes accompanying rhinitis (p < 0.05). Recurrent itchy rashes were also more likely in passive smokers (p < 0.001). Personal smoking by the 13- to 15-yr olds (8.15% boys vs. 8.8% girls ns ) resulted in a higher cumulative prevalence of wheezing (p < 0.0001), rhinitis (p < 0.05), and recurrent itchy rash (p < 0.001) but only affected current prevalence of wheezing (p < 0.0001). These smokers were more likely to experience exercise-induced wheezing (p < 0.0001), nocturnal cough (p < 0.0001), and being diagnosed with asthma (p < 0.05) and eczema (p < 0.001). Children smoking more than 10 cigarettes/day persisted with wheezing (p = 0.04) had more frequent episodes of exercise-induced wheeze (p = 0.04), nocturnal cough (p < 0.0001), and rhinoconjunctivitis (p = 0.02) than milder smokers. Smoking seems to be affecting childhood allergies in Maltese children quite significantly.