Studies have confirmed the detrimental effects of air pollutants on allergic disease patients. However, most vulnerable individuals have not been completely identified.

Two hundred twenty-five children aged 6 to 15 years with allergic rhinitis (AR) were recruited from a Taichung City hospital, Taiwan. Epidemiological study: Records of 9868 children with AR matched for study years, age, and city of the clinical research were obtained from a national database. The air pollutants included sulfur dioxide (SO2), carbon monoxide (CO), ozone (O3), particles <10 μm in diameter (PM10), particles <2.5 μm in diameter (PM2.5), nitric oxide (NO), nitrogen dioxide (NO2), nonmethane hydrocarbon (NMHC), and methane (CH4).

Positive correlations between the PRQLQ score and air pollutants were noted in boys but not in girls. After adjusting for confounders, correlations between CO, PM2.5, and NO2 levels were indicated in boys sensitized to Bt but not in those sensitized to other mites.

The study concluded that boys with AR were more vulnerable to air pollutants than girls. Bt-sensitized boys with AR were more susceptible to air pollutants than girls and those sensitized to other mites.