Home exposures, parental atopy, and occurrence of asthma symptoms in adulthood in southern Taiwan.
OBJECTIVE
Parental atopy and environmental exposures at home have been recognized risk factors for adulthood asthma. However, the relative contributions of specific risk factors and the overall contributions of heredity or home exposure remain unexplored. The purpose of this study was to identify predictors and estimate the population attributable risk (PAR) of each exposure for typical asthma symptoms among 26- to 50-year-old Taiwanese. We also investigated whether an interactive effect existed between parental atopy and home exposures on the occurrence of asthma symptoms in adulthood.


METHODS
A cross-sectional study with retrospective components.


METHODS
Elementary and middle schools in Southern Taiwan.


METHODS
Between March and October 2004, we conducted a cross-sectional survey among schoolchildren's parents from 94 elementary and middle schools in Southern Taiwan. The main outcome measure was typical asthma-like symptoms occurring within the preceding 5 years. Information on hereditary and home exposures was collected by using a self-administered questionnaire.


RESULTS
After excluding unqualified questionnaires, data from 24,784 subjects were left for analysis. New-onset asthma was reported for 0.83% of male (n = 80 of 9,662) and 1.36% of female subjects (n = 206 of 15,122). Besides parental atopic factors, environmental tobacco smoke or pet avoidance and visible mold on walls at home were independently associated with the occurrence of asthma symptoms. Mutually adjusted models produced statistically significant associations between any home exposure (odds ratio [OR], 1.80; 95% confidence interval [CI], 1.08 to 3.23; PAR, 28.04%), parental atopy (OR, 4.47; 95% CI, 3.47 to 5.75; PAR, 31.38%), and new-onset asthma. However, there was no interaction between parental atopy and home exposures.


CONCLUSIONS
Home exposures and parental atopy both increased the risks of new-onset asthma in adulthood but did not show an interactive effect. These two exposure categories approximately contributed equally to the adulthood asthma.
Department of Occupational and Environmental Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Yung-Ling
YL
Lee
Department of Internal Medicine, National Cheng Kung University, Tainan, Taiwan.
Tzuen-Ren
TR
Hsiue
Department of Internal Medicine, National Cheng Kung University, Tainan, Taiwan.
Cheng-Hung
CH
Lee
Graduate Institute of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Huey-Jen Jenny
HJ
Su
Department of Occupational and Environmental Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan. Electronic address: leonguo@mail.ncku.edu.tw.
Yueliang
Y
Leon Guo
D000328:Adult; D016902:Air Pollution, Indoor; D000485:Allergens; D001249:Asthma / Q000453:epidemiology / Q000209:etiology / Q000235:genetics*; D002648:Child; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012111:Residence Characteristics; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D014028:Tobacco Smoke Pollution
D000485:Allergens; D014028:Tobacco Smoke Pollution