Smoking Status and Factors associated with COVID-19 In-Hospital Mortality among US Veterans
Ph.D Javad Razjouyan, MD Drew A Helmer, Kristine E Lynch, MD Nicola A Hanania, MD Paul E Klotman, MD Amir Sharafkhaneh, PhD Christopher I Amos
Nicotine & Tobacco Research, doi:10.1093/ntr/ntab223
Introduction: The role of smoking in risk of death among patients with COVID-19 remains unclear. We examined the association between in-hospital mortality from COVID-19 and smoking status and other factors in the United States Veterans Health Administration (VHA). Methods: This is an observational, retrospective cohort study using the VHA COVID-19 shared data resources for February 1 to September 11, 2020. Veterans admitted to the hospital who tested positive for SARS-CoV-2 and hospitalized by VHA were grouped into Never (as reference, NS), Former (FS), and Current smokers (CS). The main outcome was in-hospital mortality. Control factors were the most important variables (among all available) determined through a cascade of machine learning. We reported adjusted odds ratios (aOR) and 95% confidence intervals (95%CI) from logistic regression models, imputing missing smoking status in our primary analysis. Results: Out of 8 667 996 VHA enrollees, 505 143 were tested for SARS-CoV-2 (NS = 191 143; FS = 240 336; CS = 117 706; Unknown = 45 533). The aOR of in-hospital mortality was 1.16 (95%CI 1.01, 1.32) for FS vs. NS and 0.97 (95%CI 0.78, 1.22; p > .05) for CS vs. NS with imputed smoking status. Among other factors, famotidine and nonsteroidal anti-inflammatory drugs (NSAID) use before hospitalization were associated with lower risk while diabetes with complications, kidney disease, obesity, and advanced age were associated with higher risk of in-hospital mortality. Conclusions: In patients admitted to the hospital with SARS-CoV-2 infection, our data demonstrate that FS are at higher risk of in-hospital mortality than NS. However, this pattern was not seen Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco 2021. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Supplementary Material A Contributorship Form detailing each author's specific involvement with this content, as well as any supplementary data, are available online at https:// academic.oup.com/ntr.
Declaration of Interests The authors do not have any competing interest.
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'abstract': '<jats:title>Abstract</jats:title>\n'
' <jats:sec>\n'
' <jats:title>Introduction</jats:title>\n'
' <jats:p>The role of smoking in risk of death among patients with COVID-19 '
'remains unclear. We examined the association between in-hospital mortality from COVID-19 and '
'smoking status and other factors in the United States Veterans Health Administration '
'(VHA).</jats:p>\n'
' </jats:sec>\n'
' <jats:sec>\n'
' <jats:title>Methods</jats:title>\n'
' <jats:p>This is an observational, retrospective cohort study using the VHA '
'COVID-19 shared data resources for February 1 to September 11, 2020. Veterans admitted to the '
'hospital who tested positive for SARS-CoV-2 and hospitalized by VHA were grouped into Never '
'(as reference, NS), Former (FS), and Current smokers (CS). The main outcome was in-hospital '
'mortality. Control factors were the most important variables (among all available) determined '
'through a cascade of machine learning. We reported adjusted odds ratios (aOR) and 95% '
'confidence intervals (95%CI) from logistic regression models, imputing missing smoking status '
'in our primary analysis.</jats:p>\n'
' </jats:sec>\n'
' <jats:sec>\n'
' <jats:title>Results</jats:title>\n'
' <jats:p>Out of 8 667 996 VHA enrollees, 505 143 were tested for SARS-CoV-2 '
'(NS = 191 143; FS = 240 336; CS = 117 706; Unknown = 45 533). The aOR of in-hospital '
'mortality was 1.16 (95%CI 1.01, 1.32) for FS vs. NS and 0.97 (95%CI 0.78, 1.22; p &gt; '
'.05) for CS vs. NS with imputed smoking status. Among other factors, famotidine and '
'nonsteroidal anti-inflammatory drugs (NSAID) use before hospitalization were associated with '
'lower risk while diabetes with complications, kidney disease, obesity, and advanced age were '
'associated with higher risk of in-hospital mortality.</jats:p>\n'
' </jats:sec>\n'
' <jats:sec>\n'
' <jats:title>Conclusions</jats:title>\n'
' <jats:p>In patients admitted to the hospital with SARS-CoV-2 infection, our '
'data demonstrate that FS are at higher risk of in-hospital mortality than NS. However, this '
'pattern was not seen among CS highlighting the need for more granular analysis with '
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'with increased risk of in-hospital mortality.</jats:p>\n'
' </jats:sec>\n'
' <jats:sec>\n'
' <jats:title>Implications</jats:title>\n'
' <jats:p>Veterans who were former smokers were at higher risk of in-hospital '
'mortality compared to never smokers. Current smokers and never smokers were at similar risk '
'of in-hospital mortality. The use of famotidine and nonsteroidal anti-inflammatory drugs '
'(NSAIDs) before hospitalization were associated with lower risk while uncontrolled diabetes '
'mellitus, advanced age, kidney disease, and obesity were associated with higher risk of '
'in-hospital mortality.</jats:p>\n'
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