Pulmonary function among children and young adults with sickle cell disease: the potential role of air pollution

Abstract Objectives Pulmonary complications heavily contribute to poor health outcomes among children with sickle cell disease (SCD). Air pollution is strongly associated with poor pulmonary health, including abnormal pulmonary function, but is understudied in SCD. This study aimed to test the hypothesis that higher ambient air pollution exposures would be associated with increased odds of abnormal lung function among children with SCD. Methods Monthly average ambient air pollution concentrations and pulmonary function tests (PFTs) were analyzed for 65 children with SCD that resided in Jefferson County, Alabama between 2010 and 2019. Logistic regressions were employed to assess the association between ambient air pollution levels and abnormal PFTs, both unadjusted and adjusted for sex, age, SCD genotype, asthma, and SCD-modifying therapies. Results Among all criteria air pollutants, elevated concentrations of nitrogen dioxide (NO2) were significantly associated with PFT abnormality. Specifically, a 1 ppb increase in monthly average NO2 concentrations was associated with a higher odds of lower function in the large/medium airways (odds ratio 1.53; 95% CI: 1.01-2.33; P = .047). Conclusion This is the first study to date demonstrating a connection between NO2 exposure and abnormal pulmonary function among children with SCD. These findings are an important contribution to the growing body of SCD-pollution literature. Given that impaired lung function is a key driver of SCD-related morbidity and mortality, this study lays the groundwork for future investigations into modifiable environmental risk factors for poor SCD-lung health.