Tobacco hypersensitivity and environmental tobacco smoke exposure in a pediatric population.

BACKGROUND

Skin testing and RAST have verified the existence of tobacco-specific IgE. However, published studies report conflicting results concerning the clinical significance of tobacco IgE. Previous studies have not focused on the role of environmental tobacco smoke (ETS) as it relates to tobacco hypersensitivity (TH) in nonsmoking children.

OBJECTIVE

We used nonsmoking pediatric patients to investigate the relationship between ETS and TH.

METHODS

Children, ages 4 to 10 years, were prospectively enrolled. ETS exposure and smoke-triggered symptoms were recorded by questionnaire and physician history. Patients were given a skin test (ST) with a panel of aeroallergens plus tobacco extract. A ST reaction to at least one aeroallergen classified a patient as atopic; a ST reaction to tobacco classified a patient as TH.

RESULTS

We enrolled 170 patients, mean age 7.2 years. We found 58 (34%) patients reported routine exposure to ETS and 78 (46%) patients reported ETS-induced symptoms. We found 121 (71%) atopic patients and 61 (36%) TH patients. TH was more common in atopic patients (P < .0001) and those routinely exposed to ETS (P < .05). However, TH failed to predict ETS-induced symptoms in either atopic or non-atopic patients (PPV = 0.40, NPV = 0.69).

CONCLUSIONS

We evaluated the clinical significance of TH in a nonsmoking patient population related to ETS exposure. We concluded that although TH is statistically related to atopy and ETS exposure, the low predictive values of skin testing for TH limit its clinical usefulness.