Passive smoking as a determinant of bronchial responsiveness in children.
The effect of passive smoking on the degree of nonspecific bronchial responsiveness (BR) in children was evaluated. In a cross-sectional survey of primary school children (7 to 11 yr) in Latium (Italy), a total of 1,215 methacholine challenge tests was performed. The children were divided into nonresponders (PC20 FEV1 > 64 mg/ml) and responders (PC20 FEV1 < or = 64 mg/ml), the latter including a subgroup of strong responders (PC20 FEV1 < or = 4.0 mg/ml). The role of passive smoking exposure was analyzed through logistic regression models. Higher odds ratios were found among girls (for strong responders: maternal smoking, OR 2.92; paternal smoking, OR 2.59); moreover, among girls there was a dose-response relationship with the number of cigarettes smoked by the mother. An effect modification was also detected for father's education and household crowding: maternal and paternal smoking were strong predictors of bronchial hyperresponsiveness in families in which the head was less educated and in overcrowded houses. The results were confirmed using a continuous index of BR (slope) and after adjustment for baseline airway caliber. We suggest that the effect of parental smoking on children's bronchial responsiveness is detectable when the conditions for a higher exposure level at home are met; females seem to be more susceptible.
Forastiere
F
F
Epidemiology Unit, Latium Regional Health Authority, Rome, Italy.
Agabiti
N
N
Corbo
G M
GM
Pistelli
R
R
Dell'Orco
V
V
Ciappi
G
G
Perucci
C A
CA
D016535:Bronchial Hyperreactivity / Q000453:epidemiology / Q000209:etiology*; D001985:Bronchial Provocation Tests; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D016210:Methacholine Chloride; D010290:Parents; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology; D012959:Socioeconomic Factors; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
D014028:Tobacco Smoke Pollution; D016210:Methacholine Chloride