[Epidemiological research on incidence of atopic disease in infants and children in relation to their nutrition in infancy].

Incidence and relative risk of atopic disease (atopic dermatitis; AD, bronchial asthma; BA, allergic rhinitis; AR) in Japanese infants and children in relation to their nutrition in infancy was analyzed from the data of the epidemiological survey which was conducted for 10,000 mothers of infants and children in 1993. A total of 4,610 replies were received: 2,714 from mothers of infants (12 months old) and 1,896 from mothers of children (2 years old). The subjects were allocated to following 3 groups based on their nutrition during first 3 months after birth; the breast-fed group (BF), the formula-fed group (EF), the mixed-fed group (MF). Incidence of atopic disease in BF, FF and MF was 23.5%, 22.2% and 21.8%, respectively and no statistical difference could be found among these 3 groups. AD was developed 17.0%, 14.4% and 13.9%; BA was 4.4%, 8.5% and 5.2%; AR was 4.9%, 6.5% and 5.8% in BF, FF and MF, respectively. Incidence of AD was significantly different between BF and MF (p < 0.01). Incidence of BA was also significantly different between BF and FF (p < 0.01). Risk of onset of BA and AR in FF was higher (adjusted odds ratio 2.2, 95% confidence interval 1.5-3.2 and adjusted odds ratio 1.5, 95% confidence interval 1.0-2.2, respectively) than that of BF controlled by age and family history with Cochran-Mantel-Haenzel test. With multiple logistic regression analysis, relative risk of the onset of BA in FF at the age of one year was 2.1, 95% confidence interval 1.2-3.5 and at the age of two years old was 2.5, 95% confidence interval 1.4-4.4. These results suggest that the breast-fed have certain suppression effects on incidence of bronchial asthma in infants and children.