COVID-19 Hospitalizations in Five California Hospitals

Importance: Characterization of a diverse cohort hospitalized with COVID-19 in a health care system in California is needed to further understand the impact of SARS-CoV-2 and improve patient outcomes. Objectives: To investigate the characteristics of patients hospitalized with COVID-19 and assess factors associated with poor outcomes. Design: Patient-level retrospective cohort study Setting: University of California five academic hospitals. Participants: Patients [≥]18 years old with a confirmed test result for SAR-CoV-2 virus hospitalized at five UC hospitals. Exposure: Confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by positive results on polymerase chain reaction testing of a nasopharyngeal sample among patients requiring hospital admission. Main Outcomes and Measures: Admission to the intensive care unit, death during hospitalization, and the composite of both outcomes. Results: Outcomes were assessed for 4,730 patients who were discharged or died during a hospitalization. A total of 846 patients were treated at UC Davis, 1,564 UC Irvine, 1,283 UC Los Angeles, 471 UC San Diego, and 566 UC San Francisco. More than 20% of patients were [≥]75 years of age (75-84: 12.3%, [≥]85: 10.5%), male (56.5%), Hispanic/Latino (45.7%), and Asian (10.3%). The most common comorbidities were hypertension (35.2%), cardiac disease (33.3%), and diabetes (24.0%). The ICU admission rate was 25.2% (1194/4730), with 7.0% (329/4730) in-hospital mortality. Among patients admitted to the ICU, 18.8% (225/1194) died; 2.9% (104/3536) died without ICU admission. The rate of the composite outcome (ICU admission and/or death) was 27.4% (1,298/4,730). While controlling for comorbidities, patients of age 75-84 (OR 1.47, 95% CI: 1.11-1.93) and 85-59 (OR 1.39, 95% CI: 1.04-1.87) were more likely to experience a composite outcome than 18-34 year-olds. Males (OR 1.39, 95% CI: 1.21-1.59), and patients identifying as Hispanic/Latino (OR 1.35, 95% CI: 1.14-1.61), and Asian (OR 1.43, 95% CI: 1.23-1.82), were also more likely to experience a composite outcome than White. Patients with 5 or more comorbidities were exceedingly likely to experience a composite outcome (OR 2.74, 95% CI: 2.32-3.25). Conclusions: Males, older patients, those with pre-existing comorbidities, and those identifying as Hispanic/Latino or Asian experienced an increased risk of ICU admission and/or death.