Study Population
The TCHS was a population-based prospective study that comprised two
cohorts of children recruited from 14 communities across Taiwan. Cohort
1 was initiated in 2007 and cohort 2 in 2010; children were aged between
9 and 12 years old at the time of enrollment; and were followed until
they turned 18 years old. Data collection includes parent- and
children-filled questionnaires on atopy diseases, adiposity measures,
pulmonary function tests, airway inflammation measures, physical fitness
assessment, pubertal development record, and oral mucosa samples for DNA
extraction. The cross-sectional analysis, involved 3233 children in
cohort 1 and 2732 children in cohort 2, with complete data on adiposity,
asthma outcomes, mediators at the age of 12 years, and genotype data.
Detailed study design and recruitment strategy have been
published15 and described on the online supplementary
file. Informed consent was obtained from all participating parents and
children. This study was approved by the ethics committee of institute
and was conducted according to the Declaration of Helsinki.
After identification of the critical mediators, we further used the
annual follow-up data which assessed the mediators from age 10 to age 12
in TCHS to approve the temporal mediating causality. The analyses herein
involved data beginning from 2010 Survey which contained adiposity
measurement, asthma outcome, puberty stage assessment, physical fitness
measurement, and pulmonary function tests. Detailed study design were
described in the online supplementary material.