AI Insight
This retrospective study analyzed electronic health records from over 1.6 million COVID-19 patients between April 2022 and March 2025 to assess how age and underlying medical conditions affect hospitalization and death rates. The research found that both advancing age and the presence of multiple underlying conditions remained strongly associated with worse outcomes, with hospitalization rates ranging from 4.7% in 20-49 year-olds to 22.6% in those 80+ years old, and mortality rates increasing from 0.11% to 3.6% across the same age groups. Individuals with two or more underlying conditions had substantially higher risks of hospitalization and death across all age categories, even in the era of widespread vaccination and treatment availability.
Why it matters
This study confirms that despite improvements in COVID-19 prevention and treatment since 2022, age and multiple underlying health conditions remain critical risk factors for severe disease outcomes. These findings can inform clinical decision-making, resource allocation, and targeted protection strategies for vulnerable populations during ongoing and future COVID-19 waves.
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⚠️ Preprint – Noch nicht peer-reviewed
Dieser Artikel wurde noch nicht von unabhängigen Experten begutachtet. Die Ergebnisse sind vorläufig und sollten mit Vorsicht interpretiert werden.
Abstract Background: COVID-19 vaccinations, therapeutics, and immunity from infection have reduced COVID-19 severity. It is unknown to what extent previously identified risk factors, age and underlying medical conditions (UC), remain associated with severe COVID-19 incidence. Methods: Using electronic health record (EHR) data from PCORnet, we identified individuals aged [≥]20 years with COVID-19 during April 2022-March 2025. We used Poisson regression with cluster-robust sandwich standard errors to estimate adjusted cumulative incidence (aCI) and aCI ratios (aCIR) for hospitalization within 16 days and mortality within 30 days of COVID-19 diagnosis to estimate the association of UCs and UC categories, comparing those with an UC to those without (adjusted for sociodemographic and health characteristics). We examined aCI and aCIR for cancer, cardiac, hepatic, immunosuppression, metabolic, neurologic, pulmonary, renal, psychiatric, and other conditions by age groups: 20-49, 50-64, 65-79, and 80+ years. Results: Among 1,662,679 patients with COVID-19, the cumulative incidence of hospitalization (4.7%, 6.3%, 10.8%, 22.6%) and mortality (0.11%, 0.42%, 1.0%, 3.6%) increased across the 20-49, 50-64, 65-79, and 80+ year old age groups, respectively. Within each age group, aCI for hospitalization and mortality increased with number of UCs, with the highest aCI among those with 3 or more UCs. aCIR by age group demonstrated that UCs, especially 2 or more, were associated with incidence of both outcomes in all age groups. Conclusion: Since 2022, older age has remained strongly associated with hospitalization and mortality after COVID-19 diagnosis. Adults with two or more UCs generally had higher incidence of both outcomes across age groups.