Biostat Student Seminar

Xiao Wu Title: Air Pollution and Mortality among Vulnerable Population Abstract: In a recent study, leveraging 16 years of data—68.5 million Medicare enrollees—we have provided strong evidence of the causal link between long-term air pollution exposure and mortality under a set of causal inference assumptions. Assessing whether long-term exposure to air pollution increases the severity of COVID-19 health outcomes, including death, is an important public health objective. Limitations in COVID-19 data availability and quality remain obstacles to conducting conclusive studies on this topic. At present, publicly available COVID-19 outcomes data for representative populations are available only as area-level counts. We describe these challenges in the context of one of the first preliminary investigations of this question in the US, where we found that higher historical PM2.5 exposures are positively associated with higher county-level COVID-19 mortality rates after accounting for many area-level confounders. Motivated by this study, we lay the groundwork for future research on this important topic, describe the complex challenges, and outline promising directions and opportunities. Research on how modifiable factors may exacerbate COVID-19 symptoms and increase mortality risk is essential to guide policies and behaviors to minimize fatality related to the pandemic. Such research could provide a strong scientific argument for revision of the US national PM2.5 standards and other environmental policies in the midst of a pandemic.