Changes in the public health burden of tobacco use during the COVID-19 pandemic: the C4R Study

Summary/Abstract Tobacco product use has been well established as a major cause of death and disease, yet the public health burden of tobacco in the context of the COVID-19 pandemic - which has already killed more than 700,000 Americans and radically altered behaviors and health in populations across the world - remains incompletely understood. Emerging evidence suggests that the personal and societal disruption of the COVID-19 pandemic has led to changes in tobacco use patterns. Reports from early in the COVID-19 pandemic provided inconsistent estimates of associations between tobacco use and risk of severe COVID-19, with some studies suggesting that smokers were at lower relative risk. This application will characterize the impact of the COVID-19 pandemic on tobacco use patterns and the association between pre-COVID tobacco use and the risk and severity of COVID- 19 illness. We will test these hypotheses in the Collaborative Cohort of Cohorts for COVID-19 Research (C4R), a nationwide study of 14 population-based multi-ethnic NIH funded cohorts, which is assessing self-reported cigarette and e-cigarette use using standardized questionnaires in over 45,000 cohort participants in whom extensive prior harmonization of pre-pandemic tobacco use patterns, socio-demographics, psychosocial factors, and comorbidities over >1 million person-years of follow-up are available. C4R is also ascertaining COVID-19 cases via questionnaires, with active surveillance in a subset, and validating cases via SARS-CoV-2 serology and protocolized events adjudication. C4R has already collected over 45,000 COVID questionnaires, over 10,000 dried blood spots for SARS-CoV-2 serology, and over 1,000 COVID-related events that are undergoing adjudication. In Aim 1, we will identify and examine changes in cigarette and e-cigarette status, intensity of use, and product mix use during the pandemic period (2020-22) compared to pre-pandemic tobacco use trajectories (1971-2019). These changes will be assessed in association with socio-demographics, psychosocial factors, comorbidities, COVID risk mitigation behavior (including vaccination), and history of COVID-19 illness. In Aim 2, we will assess whether COVID-19 outcomes, including post-acute sequelae of SARS-CoV-2 infection (PASC), are associated with pre-COVID non-cigarette tobacco use patterns (pipe, cigar, and e-cigarette), with comparison to cigarette use and never tobacco-use. Accomplishment of the Aims will support targeted public health interventions to promote smoking avoidance and cessation among groups at high risk of tobacco initiation or relapse. It will also provide valid information on whether tobacco use increases the relative risk of adverse pandemic-era health outcomes, severe COVID-19 or PASC, which will be suitable to inform public health policy and regulation.