Background: There have been few longitudinal investigations of allergic rhinitis (AR) in Chinese children. We previously conducted an investigation of the prevalence of AR in 3- to 6-year old children for the year of 2005-2006. The aim of this study was to observe the natural course of AR in children in the previously investigated population during a cohort study for 5 years.
Methods: A total of 1211 children in the previously investigated population were included in this study. Telephone interviews were conducted three times during the 1st, 3rd, and 5th year from the previous study.(14) Questions including duration, severity of nasal symptoms, asthma, and related problems of allergy were examined. Skin-prick tests (SPTs) were performed again on those children who had done SPTs in the previous study(14) after the last follow-up (i.e., after 5 years).
Results: Of the 1211 children, 870 (71.8%) completed the 5-year observation period. In the 5th year, the prevalence of positive nasal symptoms was 29.4% (256 of the 870 children), including 64/70 (91.4%) of those who were formerly symptom positive and SPT(+), 45/104 (43.3%) of those who were formerly symptom positive and SPT(-), 40/66 (60.6%) of those who were formerly symptom positive with SPTs not performed (SPTs[x]), and 107/630 (17.0%) of those who were formerly symptom negative. SPT results showed that 96.1% (73/76) of previous SPT(+) children remained SPT(+); only 3.9% (6/154) became SPT(+) in previous SPT(-) children.
Conclusion: We concluded that the natural course of AR (symptom positive and SPT(+)) and non-AR (symptom positive and SPT(-)) children were quite different.