Abstract
Background
Risk factors for COVID-19-associated hospitalizations were identified early in the pandemic. Since then, population immunity to SARS-CoV-2 has increased substantially and hospitalizations for COVID-19 have decreased. Identifying populations at greatest risk of COVID-19–associated hospitalization can help guide prevention and treatment efforts. We aimed to update information on chronic conditions as risk factors for COVID-19-associated hospitalization.
Figure.
Flow diagram of participant selection into analytic population, Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET), 2 October 2022–30 September 2023.
Methods
We compared hospitalization rates in adults aged ≥ 18 years with vs without 9 chronic conditions during 2 October 2022–30 September 2023. Rate numerators were COVID-19–associated hospitalization counts from the COVID-19–Associated Hospitalization Surveillance Network, a population-based active surveillance system with a 98-county catchment area in 13 states. Rate denominators were counts of adults with and without chronic conditions in the catchment area, estimated with US census county-level population data and state-level estimates of the adult population with and without select chronic conditions from the 2022 Behavioral Risk Factor Surveillance System. Rate ratios and 95% confidence intervals were estimated using Poisson regression with Monte Carlo simulation, adjusting for age group, sex, and race/ethnicity.
Results
Among 3,500 hospitalized adults, 74% had ≥ 1 chronic condition (Figure, Table 1). Hospitalization rates were higher among those with ≥ 1 chronic condition (vs none); adjusted rate ratios (aRR) ranged from 2.2 in adults aged ≥ 75 years to 4.6 in adults aged 18-49 years (Table 2). Among adults overall, chronic kidney disease was associated with the greatest risk of COVID-19–associated hospitalization (aRR: 4.5), followed by diabetes (2.2), history of stroke (2.0), severe obesity (2.0), coronary artery disease (1.9), COPD (1.9), smoking (1.6), and asthma (1.5); results varied by age and generally attenuated with older age (Table 2). Adjusting for number of chronic conditions, hospitalization rates were higher for adults aged ≥ 75 years relative to 18–49 years (18.5) (Table 3).
Conclusion
Of 9 chronic conditions, 8 were associated with increased risk of COVID-19–associated hospitalization with risk varying by condition and age group. Older age remains the strongest risk factor.
Disclosures
Sue Kim, MPH, Council of State and Territorial Epidemiologists: Grant/Research Support