Predicting risk for early infantile atopic dermatitis by hereditary and environmental factors

Background Hereditary and environmental factors contribute to the occurrence of atopic dermatitis (AD). However, the interaction of these two factors is not totally understood. Objectives To evaluate the early risk factors for infantile AD at the age of 6 months and to develop a predictive model for the development of AD. Methods In 2005, a representative sample of mother and newborn pairs was obtained by multistage, stratified systematic sampling from the Taiwan national birth register. Information on hereditary and environmental risk factors was collected by home interview when babies were 6 months old. Multivariate regression analysis was applied to determine the risk factors for AD in the infants. Results A total of 20 687 pairs completed the study satisfactorily. AD was diagnosed in 7.0% of 6-month-old infants by physicians. Parental asthma, atopic dermatitis and allergic rhinitis, and maternal education levels were risk factors for AD in infants. Among environmental factors, fungus on walls at home and renovation/painting in the house during pregnancy were significantly associated with early infantile AD. Using these factors, the probability of having infantile AD was estimated and grouped into low, high and very high. With five runs of tests in mutually exclusive subsets of this population, the likelihood of AD for 6-month-old infants was consistent in all the groups with the predictive model. The highest predicted probability of AD was 70.1%, among boys with maternal education levels > 12 years, both parents with AD, renovation and painting of the house during pregnancy and fungus on walls at home. The lowest probability was 3.1%, among girls with none of the above factors. Conclusions This investigation provides a technique for predicting the risk of infantile AD based on hereditary and environmental factors, which could be used for developing a preventive strategy against AD, especially among those children with a family history of atopy.