Perinatal and environmental risk factors for allergic sensitisation at the age of one

In 1997 the Prospective study on the Influence of Perinatal factors on the Occurrence of asthma and allergies (the PIPO-study) started in Antwerp. Objective: To determine perinatal and environmental risk factors for allergic sensitisation in children at the age of one. Methods: This population based cohort study included women in Antwerp and surrounding at 5 months of pregnancy. After 5-6 months of pregnancy a dust sample was taken from the mattress of the mother to determine exposure to house dust mite. A questionnaire documented possible indoor environmental risk factors for allergic sensitisation. Three months after the child was born, a dust sample was taken from the child's mattress and a second questionnaire documented in- and outdoor environmental factors. During the first year of life possible allergic symptoms were documented by weekly diaries and standardised questionnaires filled in by parents and medical services. At the age of one blood samples were taken of the child and both the parents to determine total and specific IgE-values of most common allergens. Results: Analysis of the first 260 included children revealed that 20.8% of children, 38.5% of mothers and 43.5% of fathers had at least one elevated specific IgE-value. At the age of one food allergens are the most common allergens whereas aeroallergens are the main allergens in parents. The Table shows adjusted risk factors for allergic sensitisation at the age of one. Conclusion: Allergic sensitisation in the first year of life is a complex process in which (paternal) genetic and environmental factors seem to play a part. table 141 Adjusted risk factors Odds Ratios (95% CI) p-value Male sex 2.5(1.1-5.0) 0.03 Paternal allergic sensitisation 3.5(1.3-9.8) 0.02 Maternal allergic sensitisation 0.8 (0.3-2.0) NS Breastfeeding in first 3 months 3.4(1.2-9.5) 0.02 Exposure to truck traffic 3.4 (1.2-9.5) 0.03 NS = non significant, CI = confidence interval.