Background: The prevalence of eczema in infants has increased in western societies. It has been suggested that environmental factors and the introduction of food affect the risk of eczema.
Aims: To investigate the current prevalence of eczema among infants in western Sweden, to describe current patterns of food introduction and to assess risk factors for eczema at one year of age.
Methods: Data were obtained from a prospective, longitudinal study of a cohort of infants born in the region of western Sweden in 2003; 8176 families (50% of the birth cohort) were randomly selected and, at six months of age, they received an invitation to participate, together with a questionnaire. The families that agreed received another questionnaire when the infants were twelve months old. Answers to both questionnaires and Medical birth register data were obtained for 4921 infants, i.e. 60.2% of the originally selected population.
Results: At one year of age, 20.9% of the infants had previous or current eczema. The median age at onset was four months. In the multivariable analysis, a familial occurrence of eczema, especially in siblings (OR 1.87; 95% confidence interval 1.50-2.33) or the mother (OR 1.4; 95% CI 1.30-1.84), remained as an independent risk factor. Beneficial effects of introducing fish before nine months of age (OR 0.76; 95% CI 0.62-0.94) and having a bird in the home (OR 0.35; 95% CI 0.17-0.75) were seen. We found no effects from short-term breast-feeding, the age at which milk or eggs were introduced, a cat or dog in the home or parental smoking.
Conclusions: One in five infants suffer from eczema during its first year of life. A familial occurrence of eczema increased the risk. Beneficial effects were seen from introducing fish before nine months of age or having a bird in the home. The duration of breast-feeding or the age at which milk or eggs were introduced did not affect the risk of eczema.