The Effects of Outdoor Air Pollution on Health Among People Living with Sickle Cell Disease: A Scoping Review

People with sickle cell disease (SCD) may be uniquely vulnerable and susceptible to serious health exacerbations associated with outdoor air pollution exposure. In this scoping review, we summarize evidence about impacts of outdoor air pollution exposure on health among people with SCD. Four databases were queried for peer-reviewed, primary research articles published before December 31, 2024. We identified 2246 articles, screened 1454 abstracts, and reviewed 30 full-texts. 12 studies met the inclusion criteria, and all included children in the study population. Half of the included studies were set in the United States. Further, half of the studies were published during or after 2020. Across study designs, associations were consistently positive for CO, NO 2 , PM 2.5 , and PM 10 exposures and all-cause ED visits among adults and children, yet few were statistically significant ( n = 3). This review identified a small body of literature supporting positive associations between ambient exposure to CO, NO 2 , PM 2.5 , and PM 10 and all-cause ED visits among adults and children living with SCD, and findings were consistent with prior research among other potentially susceptible groups. However, marked methodological heterogeneity across studies limited broader inferences.