Epidemiological characterization and risk factors of rhinitis and rhinoconjunctivitis among preschool children in Shanghai, China.

BACKGROUND

Previous studies have reported an increasing prevalence of childhood allergic rhinitis in developing countries. There is still a lack of the recent epidemiology of allergic rhinitis among Chinese preschool children. Therefore, this study explored the prevalence of rhinitis symptoms and identified their associations with potential risk factors among children at the age of 3-6 in Shanghai, China.

METHODS

Validated International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was adopted to collect information about rhinitis symptoms and potential risk factors. Univariate and multivariate logistic regression analyses were used to assess associations between risk factors and allergic rhinitis and rhinoconjunctivitis.

RESULTS

A total of 6183 questionnaires were included in our study. The prevalence of rhinitis ever, current rhinitis, and physician-diagnosed rhinitis were 32.6%, 29.2%, and 14.3%, respectively, while the prevalence of current rhinoconjunctivitis was 11.3%. The higher prevalence was observed in boys than in girls in terms of rhinitis ever, current rhinitis, current rhinoconjunctivitis and doctor-diagnosed rhinitis. Autumn had the highest prevalence among four seasons. In our multivariate logistic regression analyses, history of allergic diseases and paracetamol use in the last year showed positive associations with the increased risk of both current rhinitis and rhinoconjunctivitis, and antibiotic use was an independent significant risk factor only for current rhinitis. Genetic factors, including maternal and paternal rhinitis, asthma, and eczema, were significantly associated with the prevalence of current rhinitis. Similar associations were seen between these factors and current rhinoconjunctivitis, except for paternal eczema. Among environmental factors, smoking exposure at home, heavy truck traffic in home's street, floor heating system were independent risk factors for both current rhinitis and rhinoconjunctivitis in the adjusted model, while cleaning the house less than once a week was only associated with current rhinitis.

CONCLUSION

The prevalence of current rhinitis was 29.2% among children aged 3-6 in Shanghai, China. Sex differences and seasonal variations were observed in the prevalence of rhinitis symptoms. The identified risk factors would provide a basis for policy makers and medical experts to take intervention measures to prevent allergic rhinitis and rhinoconjunctivitis.