Patterns of sensitisation to common food and inhalant allergens and allergic symptoms in pre-school children.

AIM: Sensitisation to allergens and allergy symptoms depends on age, but this relationship is poorly understood. We therefore investigated the effect of age on allergen sensitisation and allergy symptoms in pre-school children.

METHODS

A cross-sectional study was conducted on 629 Korean children (age 3 to 6 years). Current allergic symptoms were assessed by the Korean version of the International Study of Asthma and Allergies in Childhood questionnaire that was adapted for pre-school children. Sensitisation to five airborne and three food allergens was evaluated by a skin prick test. χ(2) test was used to analyse differences in age trend. Multiple logistic regression analysis was performed to obtain the adjusted odds ratios (aOR) for allergic disease.

RESULTS

As age increased, the prevalence of current rhinitis (P < 0.001), the sensitisation to pollen allergens (P < 0.001) and polysensitised children (P = 0.002) increased, but the prevalence of current asthma (P = 0.010) and the sensitisation to food allergens (P = 0.009) decreased. There was no effect of age on the prevalence of current eczema (P = 0.685), monosensitised children (P = 0.282) and atopy (P = 0.160). The agreement between sensitisation to dust mites and atopy increased with age, and was 93% at age 6 years (P = 0.05). The polysensitisation (aOR = 3.0 (95% CI, 1.4-5.0), P < 0.005) and the presence of eczema in the first 2 years of life (aOR = 4.1 (95% CI, 2.2-7.6), P < 0.001) were significant independent risk factors for current rhinoconjunctivitis.

CONCLUSION

The type and number of allergen sensitisations and allergic symptoms changed from age 3 to 6 years. Careful follow-up of changes in sensitisation patterns may provide a better understanding of the pathogenesis of the allergic march.