Chronic Conditions as Risk Factors for COVID-19-Associated Hospitalization Among Adults, 2020-2023

Chronic conditions associated with COVID-19 hospitalization were identified early in the pandemic when underlying population immunity was low. Updated information on risk factors for COVID-19 hospitalization is needed.

Surveillance and cross-sectional survey data were combined to compare COVID-19 hospitalization rates in adults aged ≥18 years with and without 9 chronic conditions in 98 counties across 13 states. Hospitalization counts were obtained from the COVID-19-associated Hospitalization Surveillance Network. The adult population with and without chronic conditions was estimated from U.S. Census data and the Behavioral Risk Factor Surveillance System. Adjusted rate ratios were estimated using Poisson regression with Monte Carlo simulation, adjusting for age group, sex, and race and ethnicity.

From October 2022 through September 2023 (2022-2023), COVID-19 hospitalization rates were greater among adults with chronic kidney disease (adjusted rate ratio [95% uncertainty interval]=4.5 [3.4-5.9]), diabetes (2.2 [1.7-2.8]), stroke (2.1 [1.5-2.9]), severe obesity (2.0 [1.5-2.8]), coronary artery disease (2.0 [1.5-2.5]), chronic obstructive pulmonary disease (1.9 [1.5-2.5]), smoking (1.5 [1.2-2.0]), and asthma (1.5 [1.1-2.0]) than among adults without a given condition. Nonsevere obesity was not associated with increased risk. Hospitalization rates were 18.0 times higher among adults aged ≥75 years than among those aged 18-49 years. Hospitalized adults in 2022-2023 were more likely to be aged ≥75 years or to have ≥3 chronic conditions than in earlier seasons (2020-2022).

Of 9 chronic conditions assessed, 8 were associated with increased risk of COVID-19 hospitalization; risk varied by condition and age. Older age was the strongest risk factor. Findings can guide prevention and treatment by identifying populations at greatest risk of COVID-19 hospitalization.