ABSTRACT
A recent large survey examining over 11,000 children aged 8 to 11 years in 24 communities throughout the United States and Canada (185) found evidence for effects of ETS exposure on wheezing with colds, medical therapy for wheezing, going to a hospital emergency room for wheeze, and having persistent wheeze, the relative odds increasing with exposure level. In contrast, active doctor-diagnosed asthma and use of asthma medication were not significantly related to passive smoke exposure, possibly reflecting underdiagnosis of asthma, reporting bias, or smoking cessation by parents whose child is labeled asthmatic. Likewise, Weiss and co-workers reported a relation between persistent wheeze but not doctor-diagnosed asthma and parental smoking in 5-to 9-year-old children in East Boston ( 186). Only 34% of persistent wheezers were diagnosed as asthmatics, indicating that in this study the nonspecific symptom of wheeze may have followed noxious irritation of the airways rather than being the expression of an underlying asthmatic disease. Other cross-sectional studies failed to show an association between childhood asthma and ETS exposure ( 187-189). However, there were no reports of efforts to assess the relationship between asthma and the number of cigarettes smoked by parents or to determine the possible role of factors known to modify exposure to ETS, such as parental socioeconomic status ( 190).
