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Published on: November 5, 2021
COVID-19-Associated Mortality in US Veterans with and without SARS-CoV-2 Infection
Ayako Suzuki1,2, Jimmy T Efird3, Thomas S Redding3
1Division of Gastroenterology, Duke University, Durham, NC 27710, USA.
Insights
Risk factors like age and obesity increase mortality for SARS-CoV-2 (COVID-19) patients compared to uninfected individuals. However, current smoking and alcohol use disorder were linked to lower mortality in infected men.
Area of Science:
- Public Health
- Epidemiology
- Infectious Disease Research
Background:
- Risk factors for coronavirus disease 2019 (COVID-19) are well-documented.
- Few studies have compared these risk factors in infected individuals against uninfected populations.
Purpose of the Study:
- To assess how risk factors influence 30-day mortality in SARS-CoV-2-infected subjects relative to uninfected subjects.
- To compare the differential impact of risk factors on mortality between infected and uninfected individuals.
Main Methods:
- Observational Veterans Health Administration cohort analysis of 341,166 male veterans tested for SARS-CoV-2.
- Relative risk of 30-day mortality computed for age, race, ethnicity, BMI, smoking status, and alcohol use disorder.
- Difference in relative risk evaluated between infected and uninfected subjects, adjusting for clinical confounders.
Main Results:
- 7% of the cohort tested positive for SARS-CoV-2.
- Advanced age (>60) and overweight/obesity correlated with increased mortality risk in infected individuals.
- Current smoking and alcohol use disorder were associated with decreased mortality risk in infected individuals compared to uninfected.
Conclusions:
- Age, BMI, smoking, and alcohol use disorder differentially affect 30-day mortality in SARS-CoV-2-infected versus uninfected individuals.
- Infected men experienced increased mortality with advanced age and obesity, but decreased mortality with current smoking and alcohol use disorder.
- Findings highlight unique mortality risk profiles associated with COVID-19 infection.
Background:
We performed an observational Veterans Health Administration cohort analysis to assess how risk factors affect 30-day mortality in SARS-CoV-2-infected subjects relative to those uninfected. While the risk factors for coronavirus disease 2019 (COVID-19) have been extensively studied, these have been seldom compared with uninfected referents.
Methods:
We analyzed 341,166 White/Black male veterans tested for SARS-CoV-2 from March 1 to September 10, 2020. The relative risk of 30-day mortality was computed for age, race, ethnicity, BMI, smoking status, and alcohol use disorder in infected and uninfected subjects separately. The difference in relative risk was then evaluated between infected and uninfected subjects. All the analyses were performed considering clinical confounders.
Results:
In this cohort, 7% were SARS-CoV-2-positive. Age >60 and overweight/obesity were associated with a dose-related increased mortality risk among infected patients relative to those uninfected. In contrast, relative to never smoking, current smoking was associated with a decreased mortality among infected and an increased mortality in uninfected, yielding a reduced mortality risk among infected relative to uninfected. Alcohol use disorder was also associated with decreased mortality risk in infected relative to the uninfected.
Conclusions:
Age, BMI, smoking, and alcohol use disorder affect 30-day mortality in SARS-CoV-2-infected subjects differently from uninfected referents. Advanced age and overweight/obesity were associated with increased mortality risk among infected men, while current smoking and alcohol use disorder were associated with lower mortality risk among infected men, when compared with those uninfected.
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