Older Age is Strongest Risk Factor Associated with Mechanical Ventilation and Death among Veterans with COVID-19

BACKGROUND:
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a very broad spectrum of clinical severity that ranges from asymptomatic infection to life-threatening illness. It remains unclear why some patients infected with SARS-CoV-2 develop the severe complications of coronavirus disease 2019 (COVID-19), which can result in death. Multiple risk factors for developing severe COVID-19 disease have been reported, however, most prior studies, particularly those published earlier in the pandemic, did not include multivariable adjustment to identify independent risk factors, and few studies examined a range of different disease outcomes, including hospitalization, mechanical ventilation, and death. Thus, this retrospective cohort study sought to identify risk factors associated with hospitalization, mechanical ventilation, and death among patients with COVID-19 infection. Using VA data, investigators identified 88,747 Veterans who were tested within VA for COVID-19 between February 28 and May 14, 2020,11% of whom (10,131) tested positive.

FINDINGS:

• Veterans who tested positive were more likely to be Black (42% vs 25%), obese (45% vs 40%), and to live in states with a high burden of COVID-19 compared to Veterans who tested negative.
• Veterans who tested positive for COVID-19 had a 4.2-fold risk of mechanical ventilation and a 4.4-fold risk of death compared with Veterans who tested negative.
• Most COVID-19 deaths among Veterans in this study were attributed to age 50 and older (64%), male sex (12%), and greater comorbidity burden (11%). Many factors previously reported to be associated with mortality in smaller studies were not confirmed, including Black race, Hispanic ethnicity, COPD, hypertension, and smoking.
• Other risk factors for mortality among Veterans with COVID-19 included select pre-existing comorbid conditions, such as heart failure, chronic kidney disease, and cirrhosis.

IMPLICATIONS:

• Some risk factors may be reversible or modifiable, thereby reducing the mortality rate of SARS-CoV-2, or they may provide clues as to the pathogenesis of severe, life-threatening SARS-CoV-2.

LIMITATIONS:

• Hospitalizations or mechanical ventilations that occurred outside VA and were not paid for by VA were not included in this analysis. Also, these results are limited to Veterans who were tested for COVID-19 with the VA healthcare system.

AUTHOR/FUNDING INFORMATION:
This study was partly funded by CSR&D. Drs. Ioannou, O’Hare, Dominitz, and Fan are with HSR&D’s Center of Innovation for Veteran-Centered & Value-Driven Care in Seattle, WA and Denver CO, and all authors are part of the VA Puget Sound Health Care System.

Ioannou G, Locke E, Green P, Berry K, O’Hare A, Shah J, Crothers K, Eastment M, Dominitz J, and Fan V. Risk Factors for Hospitalization, Mechanical Ventilation, or Death among 10,131 Veterans with SARS-CoV-2 Infection. JAMA Network Open. September 23, 2020;3(9):e2022310.