The
risk of
asthma has been increasing in parallel with use of
acetaminophen, which is a potential source of
oxidative stress.
Toll-like receptor 4 (TLR4)
plays a critical
role not only in
innate immunity, but also in
mediating reactive oxygen species induced
inflammation. Therefore, we investigated
associations between
acetaminophen usage and TLR4 polymorphism on
asthma and bronchial hyperresponsiveness (BHR). The number of 2,428
elementary school children in
Seoul and Jeongeup cities was recruited. Subjects
who used
acetaminophen with a
family history of
asthma had an increased
risk of both
asthma diagnosis ever and current
asthma. Individuals with CT+TT
genotypes at the TLR4 polymorphism, in combination with
acetaminophen usage, also demonstrated an increased
risk of
asthma diagnosis ever (aOR, 2.08; 95%
confidence interval [CI], 1.10-3.92).
Family history of
asthma and
acetaminophen usage were
risk factors for BHR. Although TLR4 was not an independent
risk factor for BHR, individuals with CT+TT
genotypes at the TLR4 polymorphism had an increased
risk of BHR when combined with
acetaminophen usage (aOR, 1.74; 95% CI, 1.03-2.94). In conclusion,
acetaminophen usage may be associated with
asthma and BHR in genetically susceptible subjects. This effect may be modified by polymorphism at TLR4.