PARENTAL HISTORY AND THE RISK FOR CHILDHOOD ASTHMA - DOES MOTHER CONFER MORE RISK THAN FATHER

Although heredity plays a major role in asthma and in other allergic d iseases, mechanisms underlying the inheritance of these disorders are poorly understood, as is the relative contribution of maternal and pat ernal conditions to risk of disease. We investigated doctor-diagnosed maternal and paternal asthma, eczema, and hay fever as cross-sectional predictors of childhood asthma and allergic disease in 306 children w ith a median age of 3.5 yr from families in which at least one parent had a history of either asthma or other allergic conditions. For both childhood asthma and eczema, the strongest parental predictors were th e same conditions in the parents. For asthma in particular, maternal a sthma was most strongly associated with asthma in the child over all a ges in both univariate (OR = 3.2, 95% CI = 1.5 to 6.7) and multivariab le (OR = 41, 95% CI = 1.7 to 10.1) models. Paternal asthma was weakly associated with childhood asthma in the univariate model (OR = 1.4 95% CI = 0.6 to 3.2), but this association increased in magnitude in the multivariable model (OR = 2.7, 95% CI = 1.0 to 7.2). Among the childre n < 5 yr of age, the risk for childhood asthma associated with materna l asthma (OR = 5.0, 95% CI = 1.7 to 14.9) was greater than the risk as sociated with paternal asthma (OR = 1.6, 95% CI = 0.5 to 5.9), whereas both maternal asthma and paternal asthma were associated with similar risks among children greater than or equal to 5 yr of age (OR = 4.6, 95% CI = 1.1 to 19.0 and OR = 4.1, 95% CI = 1.0 to 16.0, respectively) . The odds of having a child with asthma were three times greater in f amilies with one asthmatic parent and six times greater in families wi th two asthmatic parents than in families where only one parent had in halant allergy without asthma; furthermore, inhalant allergy in one pa rent also conferred additional risk in the presence of asthma in the o ther parent. Further investigation is needed into the relative importa nce of genetic factors and in utero and postnatal exposures in determi ning the differential effects of maternal and paternal asthma on the d evelopment of childhood asthma.