Objectives: Administrative criteria are often used to define COVID-19 outcomes despite challenges in differentiating hospitalization “for” vs “with” COVID-19 and unknown reliability for identifying COVID-related cardiopulmonary complications. We implemented a protocol to adjudicate COVID-related events across 14 studies participating in C4R. Methods: C4R cohorts ascertained COVID-related hospitalizations and deaths via questionnaires or ongoing surveillance. Medical records were reviewed by C4R physicians using a standardized protocol to assign COVID-related diagnoses as definite or probable. C4R diagnoses were compared against ICD codes assigned to the events. This report includes data from events centrally adjudicated by C4R as of September 2022. Results: Among 144 events ascertained across 7 cohorts as potentially COVID-related, SARS-CoV-2 infection was confirmed in 107/117 (91%) non-fatal hospitalizations and 26/27 (96%) deaths. Of confirmed infections, COVID-19 illness was diagnosed as the cause of 101/107 (94%) hospitalizations and 24/26 (92%) deaths ( Table ). Of non-fatal hospitalizations with infection, 72% were diagnosed with severe or critical COVID-19, 78% with COVID-associated pneumonia, and 29% with renal failure; other complications were less common. C4R review did not validate diagnoses indicated by ICD codes for 1 COVID-19 infection, 5 pneumonias, 1 stroke, and 7 renal failure cases. C4R review did identify diagnoses that were not ICD-coded for 13 infections, 31 pneumonias, 6 myocardial infarctions, 5 venous thromboses, and 21 renal failure cases. Conclusions: Protocolized medical records review by C4R confirmed COVID-19 as the cause of hospitalization or death in 87% of events ascertained as potentially COVID-related and 94% of those in which SARS-CoV-2 infection was confirmed. Both false-positive and false-negative misclassification by ICD criteria was observed. Protocolized review may be useful to identify and validate COVID-related events for epidemiologic research.
Abstract P461: Changes in Cigarette Smoking Patterns During the COVID-19 Pandemic: The C4R Study
Rationale: The impact of the COVID-19 pandemic on tobacco use patterns remains incompletely understood. We aimed to examine changes in cigarette smoking patterns over the first 2 years of the COVID-19 pandemic (2020-22) in a large, multiethnic, US community-based sample. Methods: The Collaborative Cohort of Cohorts for COVID-19 Research (C4R) ascertained the impact of the COVID-19 pandemic on participants from 14 longitudinal NIH-funded cohorts via 2 waves of standardized questionnaires conducted 2020-22. The C4R questionnaire collected data on cigarette use patterns for the current and immediate pre-pandemic periods (January-March 2020). These data were used to define pandemic-era smoking initiation, smoking cessation, and changes in smoking intensity. Multivariable logistic regression models were adjusted for centrally harmonized pre-pandemic data on sociodemographic characteristics, remote smoking history, and co-morbidities and pandemic-era psychological health, insomnia, and SARS-CoV-2 infection history ascertained through C4R questionnaires. Multiple imputation by chained equations was used to account for missing covariate data. Results: Of 17179 participants completing C4R questions on pandemic-era smoking behaviors, 1899 (11%) participants reported current smoking in the immediate pre-pandemic period (mean age 70 years, 59% women, 31% African American, 2% Hispanic, 1% Asian, 22% American Indian/Alaskan Native [AIAN]). Of these 181 (10%) self-reported quitting during the pandemic. Among 1718 (90%) who continued smoking, smoking intensity increased in 17% and decreased in 26%. Among 15093 participants who were not smoking prior to March 2020, 135 (0.9%) initiated smoking during the pandemic period, including 120 (89%) with a remote history of smoking and 15 (11%) with no history of smoking. Pandemic-era smoking cessation was associated with older age(80+ years vs <65 years [adjusted odds ratio; 95%CI] 2.1; 1.1-4.0), obesity(vs normal weight 1.6; 1.02-2.6) and history of SARS-CoV-2 infection (2.1; 1.3-3.1). Pandemic-era smoking initiation was associated with concurrent use of cannabis (3.1; 1.9-5.2), e-cigarette (29.6; 14.8-59.2), and/or alcohol (1.8; 1.1-2.9). Compared to non-Hispanic white participants, AIAN participants had lower odds of quitting (0.1; 0.03-0.6) and African American participants had higher odds of increased smoking intensity (2.0; 1.3-3.1). Depressive symptoms were associated with smoking initiation (2.4; 1.3-4.3) and increased smoking intensity (2.6; 1.5-4.5). Conclusion: Greater odds of smoking initiation and/or increased smoking intensity were observed in minoritized groups and participants reporting depressive symptoms. Majority of those who initiated smoking during pandemic-era were relapsers. Smoking cessation programs remain important to improving public health and reducing health disparities.