Journal of Smoking Cessation

Review Article

The Impact of Tobacco Use on COVID-19 Outcomes: A Systematic Review

Table 2

Study characteristics and results.
AuthorMonth and yearLocationStudy designParticipantsSmokersMortalityHospitalizationICU admissionMechanical ventilationSeverity
Parra-Bracamonte, G.M. et al.Dec 2020MexicoRetrospective cohort331,29824,484 (7.4%),
Ioannou, G.N. et al.Sept 2020USALongitudinal multicenter cohort10,1315,212 (51.4%)NSNSNS
Ho, K.S. et al.Dec 2020USARetrospective multicenter cohort9,9912,212 (22.1%); 1,279 (26.1%) hospitalizedNSNSNSNS
Bello-Chavolla, O.Y. et al.June 2020MexicoRetrospective cohort20,8041,815 (8.7%)NS, NS
Pérez-Sastré, M.A. et al.July 2020MexicoRetrospective cohort16,7521,340 (8%)NSNS,
Lowe, K.E. et al.Jan 2021USARetrospective multicenter cohort7,1021,082 (15.2%), (>30 pkyr), NS for less (10-30 pkyr) & 2.25 (+30 pkyr), (10-30) and 1.69 (+30),
Lohia, P. et al.Feb 2021USARetrospective multicenter cohort1,871704 (37.6%), ; aOR NS, NS
Hamer, M. et al.July 2020UKProspective cohort387,109 (760 with COVID-19)406 (53.4%) (37k/9.7% current smokers in whole cohort),
Vilches-Moraga, A. et al.Dec 2020UK & ItalyMulticenter observational cohort831361 (43.4%)
Kim, D. et al.Sept 2020USARetrospective observational multicenter cohort867354 (40.7%), (current smokers), NS for formerNS
Adrish, M. et al.Oct 2020USARetrospective cohort1,173336 (28.6%)NS47% smoke vs. 37% nonsmoke, 47% smoke vs. 37% nonsmoke,
Di Castelnuovo, A. et al.Oct 2020ItalyRetrospective observational multicenter cohort3,894319 (8.2%)NS
Raines, A.M. et al.Feb 2021USARetrospective cohort440250 (56.8%),
Islam, M.Z. et al.Oct 2020BangladeshRetrospective single center cohort1,016185 (18.2%); 40 smokeless tobacco (3.9%), , ;
aOR for smokeless NS		NS
Saurabh, S. et al.Jan 2021IndiaProspective unmatched case-control study91180 (8.8%); 139 (15.3%) smokeless tobaccoNSNS
Soares, R.C.M. et al.Sept 2020BrazilRetrospective multicenter cohort10,713209 (1.95%)NS,
Alharthy, A. et al.Oct 2020Saudi ArabiaRetrospective single center cohort352174 (49.4%),
Abohamr, S.I. et al.Nov 2020Saudi ArabiaRetrospective case series768160 (20.8%), ,
Garassino, M.C. et al.July 20208 countriesCross-sectional & longitudinal multicenter observational cohort196159 (81.1%),
Abbas, H.M. et al.Sept 2020IraqCross-sectional observational follow-up284141 (49.6%), (smoke only); , (smoke + diabetes)NS
Ullah, A.D. et al.Oct 2020UKRetrospective single-center cohort212126 (59.4%)NS
Ragab, E. et al.Nov 2020EgyptRetrospective cohort240116 (48.3%),
Chen, L. et al.Aug 2020ChinaRetrospective multicenter cohort1,859111 (6%),
Killerby, M.E. et al.June 2020USARetrospective cohort53191 (17.1%),
Chetboun, M. et al.Sept 20206 countriesRetrospective multicenter cohort1,46183 (6.5%) (data for 1,275)NSNS
Chand, S. et al.Oct 2020USARetrospective case series30067 (22.3%),
Palaiodimos, L. et al.July 2020USARetrospective cohort20065 (32.5%)NS,
Badr, O. et al.Feb 2021Saudi ArabiaRetrospective case-control15961 (38.4%)NS
Sapienza, L,G. et al.Jan 2021USARetrospective cohort (2 sites)15456 (36.4%),
Bellan, M. et al.Nov 2020ItalyRetrospective multicenter cohort1,697 (407 assessed for predictors of mortality)54 (17%),
Almazeedi, S. et al.July 2020KuwaitRetrospective cohort109644 (4%), ,
Ferrari, B.L. et al.Jan 2021BrazilLongitudinal multicenter cohort19841 (21%),
Wallis, T. et al.Jan 2021UKProspective single center cohort10135 (35%)
Preprints
Wang, A. et al.June 2020USARetrospective multicenter cohort7,5921,572 (20.7%), (former); NS for current
Israel, A. et al.June 2020IsraelCase-control24,906 (4,151 cases)889 (21.4%) (cases)NSNS
Khawaja, A. et al.May 2020UKProspective cohort406,793 (605 with COVID-19)331 (54%) (40k/10% current smokers in whole cohort),
Romero, G.F. et al.Nov 2020USARetrospective cohort577268 (46.4%), (former); NS for currentNSFormer: 15.5% (), current: 19.8% ()
Mendy, A. et al.June 2020USARetrospective multicenter cohort689170 (24.7%)NS, , NS
Hasan, M. et al.Jan 2021BangladeshProspective observational cohort600106 (17.6%)
OR: odds ratio; aOR: adjusted odds ratio; HR: hazard ratio; RR: relative risk; NS: not significant; pkyr: pack years. Not assessed.