Abstract
The prevalence of allergic diseases in school children was examined both in 1992 (46, 718 children) and in 2002 (36, 228 children) in 11 western districts of Japan. Both studies were conducted with the same questionnaire in the same districts.
Results:
1) The study in 2002 established prevalence rate of 20.5% in allergic rhinitis (AR), 13.8% in atopic dermatitis (AD), 9.8% in allergic conjunctivitis (AC), 6.5% in bronchial asthma (BA), 5.7% in Japanese cedar pollinosis (P), 5.3% in wheeze, respectively. These rate were higher than those of 10 years ago except AD.
2) The prevalence rate of allergic diseases was 31.3% in 1992 and 34.1% in 2002. The cumulative rate was 45.5% in 1992 and 56.3% in 2002.
3) Higher prevalence rates were found in children who lived in urban area, but area's differences in 2002 survey were smaller than those in 1992 survey.
Higher prevalence rates of AR, AC and P were found in elder children, and W was found in younger children. No differences were found in AD or BA.
4) There was slight difference among nutrition during infancy, indoor smoking, type of heating or air conditioning.
5) Higher prevalence were found in children who had family history of allergic diseases and early history of lower respiratory infectious diseases.
