Association between parental socioeconomic position and prevalence of asthma, atopic eczema and hay fever in children

Aim: To determine the prevalence of asthma, atopic eczema and hay fever among children in different age groups and examine the associations with parental socioeconomic position. Methods: A cross-sectional health survey of four complete birth-cohorts in the municipality of Copenhagen was conducted. Children aged 11 and 15 years and parents of children aged 3 and 6 years completed questionnaires on symptoms and diseases. Data were linked to national registers on demographics and socioeconomic position measured as education, employment and income. In total, 9720 children/parents responded (50.5%). Results: The prevalence of asthma and hay fever increased with increasing age; asthma: from 3.2% among children aged 3 years to 15.4% among children aged 15 years; hay fever: from 3.1% among children aged 3 years to 21.3% among children aged 15 years. The prevalence of atopic eczema did not vary with age and ranged between 15.5% and 17.8%. Odds Ratios for children of parents with the lowest vs. the highest educational level were 1.50 (95% CI = 1.17-1.91) for asthma; 1.68 (95% CI = 1.35-2.10) for hay fever; and 0.75 (95% CI = 0.64-0.89) for atopic eczema. Unemployment was significantly associated with a decreased risk of atopic eczema and eczema symptoms. There was no independent association between household income and any of the outcomes. Conclusions: The prevalence of asthma and hay fever, but not atopic eczema, increased with increasing age. Atopic eczema was associated with high parental educational level, whereas asthma and hay fever were associated with low educational level. No association with household income was found.