Risk Factors Associated With In-Hospital Mortality in a US National Sample of Patients With COVID-19

This cohort study characterizes patients with coronavirus disease 2019 (COVID-19) who were treated in US hospitals and examines risks factors associated with in-hospital mortality. Importance Coronavirus disease 2019 (COVID-19) has infected more than 8.1 million US residents and killed more than 221 000. There is a dearth of research on epidemiology and clinical outcomes in US patients with COVID-19. Objectives To characterize patients with COVID-19 treated in US hospitals and to examine risk factors associated with in-hospital mortality. Design, Setting, and Participants This cohort study was conducted using Premier Healthcare Database, a large geographically diverse all-payer hospital administrative database including 592 acute care hospitals in the United States. Inpatient and hospital-based outpatient visits with a principal or secondary discharge diagnosis of COVID-19 (International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis code, U07.1) between April 1 and May 31, 2020, were included. Exposures Characteristics of patients were reported by inpatient/outpatient and survival status. Risk factors associated with death examined included patient characteristics, acute complications, comorbidities, and medications. Main Outcomes and Measures In-hospital mortality, intensive care unit (ICU) admission, use of invasive mechanical ventilation, total hospital length of stay (LOS), ICU LOS, acute complications, and treatment patterns. Results Overall, 64 781 patients with COVID-19 (29 479 [45.5%] outpatients; 35 302 [54.5%] inpatients) were analyzed. The median (interquartile range [IQR]) age was 46 (33-59) years for outpatients and 65 (52-77) years for inpatients; 31 968 (49.3%) were men, 25 841 (39.9%) were White US residents, and 14 340 (22.1%) were Black US residents. In-hospital mortality was 20.3% among inpatients (7164 patients). A total of 5625 inpatients (15.9%) received invasive mechanical ventilation, and 6849 (19.4%) were admitted to the ICU. Median (IQR) inpatient LOS was 6 (3-10) days. Median (IQR) ICU LOS was 5 (2-10) days. Common acute complications among inpatients included acute respiratory failure (19 706 [55.8%]), acute kidney failure (11 971 [33.9%]), and sepsis (11 910 [33.7%]). Older age was the risk factor most strongly associated with death (eg, age >= 80 years vs 18-34 years: odds ratio [OR], 16.20; 95% CI, 11.58-22.67; P < .001). Receipt of statins (OR, 0.60; 95% CI, 0.56-0.65; P < .001), angiotensin-converting enzyme inhibitors (OR, 0.53; 95% CI, 0.46-0.60; P < .001), and calcium channel blockers (OR, 0.73; 95% CI, 0.68-0.79; P < .001) was associated with decreased odds of death. Compared with patients with no hydroxychloroquine or azithromycin, patients with both azithromycin and hydroxychloroquine had increased odds of death (OR, 1.21; 95% CI, 1.11-1.31; P < .001). Conclusions and Relevance In this cohort study of patients with COVID-19 infection in US acute care hospitals, COVID-19 was associated with high ICU admission and in-hospital mortality rates. Use of statins, angiotensin-converting enzyme inhibitors, and calcium channel blockers were associated with decreased odds of death. Understanding the potential benefits of unproven treatments will require future randomized trials. Question What are the epidemiologic characteristics of patients with coronavirus disease 2019 (COVID-19) treated in US hospitals, and what risk factors are associated with mortality? Findings In this cohort study of 64 781 patients with COVID-19 treated in 592 US hospitals during April and May 2020, the in-hospital mortality rate was 20.3% among inpatients, and severe complications were common. Receipt of statin, angiotensin-converting enzyme inhibitors, and calcium channel blockers were associated with decreased odds of mortality, but the combination use of hydroxychloroquine and azithromycin was associated with increased odds of mortality. Meaning In this study, COVID-19 was associated with severe complications and deaths among patients hospitalized in the United States; certain medications may be associated with decreased odds of mortality.