ISEE 2007 CONFERENCE ABSTRACTS SUPPLEMENT: Abstracts
The prevalence of atopic eczema in adolescents has recently been reported as increasing in many countries, a phenomenon yet to be fully explained. This study compared the prevalence of atopic eczema among Taiwanese adolescents with individual-level risk factors and community-level data of temperature, relative humidity, and air pollutants to determine whether changes in these factors could explain the observed change in prevalence.
Material and Methods:
We conducted 2 nationwide, cross-sectional surveys of atopic illness and symptoms among 12- to 15-year-old Taiwanese schoolchildren in 1995 to 1996 and 2001. The effects of personal and environmental factors were assessed and temporal changes of outdoor monitoring data were also compared with prevalence difference of atopic eczema.
A total of 42,919 adolescents from the 1995 to1996 survey and 10,215 adolescents from the 2001 survey attended schools located within 1 km of 22 monitoring stations. The 12-month prevalence of atopic eczema increased significantly during this period [adjusted prevalence ratio (PR) = 1.43, 95% confidence interval (CI) 1.21–1.70 in boys; PR = 1.77, 95% CI 1.49–2.10 in girls]. After adjustment for potential risk factors, the prevalence differences were statistically unchanged. Although parental education level contributed the most, changes in personal and environmental factors might not explain the observed prevalence increases of atopic eczema. Temporal change in relative humidity was significantly associated with prevalence increase among boys but its contribution was also small.
Correlates of the investigated risk factors that have changed over time still underlie the prevalence increases of atopic eczema in Taiwanese adolescents. The exact reasons for the rising trends remain to be elucidated.