key: cord-0987131-kivmqfqy
authors: Merianos, Ashley L.; Russell, Alex M.; Mahabee-Gittens, E. Melinda; Barry, Adam E.; Yang, Meng; Lin, Hsien-Chang
title: Assessment of Exclusive, Dual, and Polytobacco E-Cigarette Use and COVID-19 Outcomes Among College Students
date: 2022-03-03
journal: Am J Health Promot
DOI: 10.1177/08901171211055904
sha: 5da550d2c08e636d81d0e01a565558ba0e246162
doc_id: 987131
cord_uid: kivmqfqy

PURPOSE: This study examined current (past 30-day) dual- and polytobacco use patterns and COVID-19 symptomatology, testing, and diagnosis status among college student electronic cigarette (e-cigarette) users. DESIGN: Cross-sectional online questionnaire administered during October–December 2020. SETTING: Four large, U.S. public universities in geographically diverse locations. SAMPLE: College students (N=756) ages 18–24 who reported current e-cigarette use. MEASURES: Current use of e-cigarettes, combustible cigarettes, and cigars, and self-reported COVID-19 symptomatology, testing, and diagnosis status were measured. ANALYSIS: Multivariable logistic regression models accounting for students’ demographics, university site, fraternity/sorority membership, and current residence. RESULTS: Over half (53.6%) of students were exclusive e-cigarette users, 20.4% were dual e-cigarette and combustible cigarette users, 4.6% were dual e-cigarette and cigar users, and 21.4% were poly users of e-cigarettes, combustible cigarettes, and cigars. Compared to exclusive e-cigarette users, dual users of e-cigarettes and combustible cigarettes (AOR=2.12, 95%CI=1.05–4.27) and poly users of e-cigarettes, combustible cigarettes, and cigars (AOR=3.70, 95%CI=1.78–7.70) had increased odds of COVID-19 symptomatology, even when accounting for covariates. While current tobacco use groups did not differ based on COVID-19 testing, polytobacco users had significantly increased odds (AOR=2.16, 95%CI=1.11–4.20) of having received a positive COVID-19 diagnosis. CONCLUSION: Given use of two or more tobacco products increased COVID-19-related risks, results underscore the need to prevent dual- and polytobacco use behaviors in college student e-cigarette users.

"In Brief"

The study objective was to examine the associations between current (past 30-day) dual-and polytobacco use patterns and COVID-19 symptomatology, testing, and diagnosis status among college student electronic cigarette (e-cigarette) users. Dual e-cigarette and combustible cigarette users and poly users of e-cigarettes, combustible cigarettes, and cigars were at increased odds of having current COVID-19 symptomatology, compared to exclusive e-cigarette users. While no differences were found between tobacco use groups based on COVID-19 testing, when compared with exclusive e-cigarette users, polytobacco users were at increased odds of having a positive COVID-19 diagnosis. The current study provides information on COVID-19-related risks associated with dual-and polytobacco use of e-cigarettes with combustible tobacco products among young adults. Prevention efforts are urgently needed to prevent and reduce dual-and polytobacco use behaviors in college student e-cigarette users, especially during the current COVID-19 pandemic.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing coronavirus disease 2019 (COVID- 19) , has caused a pandemic resulting in nearly 200 million cases and over four million deaths. 1 Tobacco users are at increased risk for respiratory viruses, and tobacco smoking and potentially electronic cigarette (e-cigarette) use can upregulate the known SARS-CoV-2 receptor. 2 Recently published meta-analyses suggest a direct association between combustible cigarette smoking and COVID-19 disease progression, 3 severity, and death. 4 Specifically, COVID-19 patients who were current smokers were at nearly two-fold odds of COVID-19 disease progression, 3 and about 1.5-fold odds of COVID-19 severity and risk of death compared to patients who were never smokers. 4 While past 30-day (current) combustible cigarette smoking continues to decline significantly among U.S. college students, with a 2019 prevalence of about 8%, vaping nicotine has increased to 22% among this population. 5 Associations between current dual use of combustible cigarettes and ecigarettes and COVID-19 symptomatology, testing, and diagnosis have been reported among youth and young adults. 6 When compared to never users, current dual-users of e-cigarettes and combustible cigarettes were at nearly five-fold odds of reporting COVID-19-related symptoms, nine-fold odds of reporting COVID-19 testing, and nearly seven-fold odds of reporting a positive COVID-19 diagnosis. However, a research gap remains on polytobacco use and COVID-19 outcomes among the college student population. Given concerns about the potential endemic nature of COVID-19, 7 and high e-cigarette use among college students, 5 there is a need to gain a better understanding of the link between polytobacco use and COVID-19-related outcomes among this high-risk population. Consequently, the current study examined dual-and polytobacco use patterns and COVID-19 symptomatology, testing, and diagnosis status among a sample of college student ecigarette users in the U.S.

College students reporting past 30-day e-cigarette use from four large, geographically diverse U.S. universities were recruited to participate in an online survey between October 2020 and December 2020. Located in Arkansas, Indiana, Ohio, and Texas, each of the four participating universities are public, 4-year doctoral institutions with very high research activity and have a student population ranging from 28,000-68,000. 8 Data collection at each university was planned to begin in the middle of fall semester of 2020 due to the overall study's objective of measuring past 30-day tobacco product use behavior among students on campus during the academic year. Due to the COVID-19 pandemic, all four universities offered similar course format options to students for them to complete their coursework in an online format, in-person format, or hybrid format. Despite the COVID-19 pandemic, each campus remained open to students and allowed students to live in on-campus housing during data collection in the fall semester. COVID-19 testing programs were similar among the four campuses, which required selected students to participate in random testing.

Institutional review boards at each institution vetted and approved study procedures by November 2020. Upon receiving IRB approval, data collection began at each respective school, occurring between October 2020 and December 2020. Potential participants were recruited at each respective university by disseminating email invitations widely using undergraduate and graduate course listservs as well as campus-wide listservs. The email invitation described the study's purpose, which also included a link to a research information sheet and Qualtrics survey. 9 Students who clicked the website link had to first acknowledge reading the research information sheet and then proceed to the initial survey questions that confirmed they were eligible for participation. Students who met these eligibility criteria were then asked the main survey questions, which took approximately 10 min to complete. Three universities provided $10 incentives to students for survey completion. The university in Ohio was unable to offer monetary incentives to students for participation at the time of survey completion due to a student financial aid policy.

College students eligible for participation in the overall study were between the ages of 18-26 years, used an e-cigarette or vaping device in the past 30 days, and were currently on campus. For the purpose of the current study, we excluded student e-cigarette users who were ages 25-26 years due to differing age trends of tobacco product use among older age groups. 5,10 A total of 756 student current (past 30-day) ecigarette users who were ages 18-24 years were included in the current study. Participants provided written informed consent by acknowledging the research information sheet before proceeding to the survey. Due to the nature of sending participation invitations via campus listservs, response rates could not be calculated. We calculated the needed sample size with a 95% confidence interval based on a 100,000-population size and a conservative 50-50 split where the population is assumed to be relatively varied. 11 Based on this calculation, we estimated we needed a minimum of 383 completed surveys for the current study's final sample size in order to have sufficient power for the statistical analysis.

Current tobacco use. Participants were asked the following question to confirm current e-cigarette use: "During the past 30 days, on how many days did you use an electronic vapor product?" Response options ranged from 0-30 days. Electronic vapor products were defined as e-cigarettes, vapes, vape pens, e-cigars, e-hookahs, hookah pens, and mods, and brand examples were provided (eg, JUUL). All participants reported current use on ≥1 day in the past 30 days. To determine current dual-and polytobacco use, current e-cigarette users were asked two questions about their past 30-day combustible tobacco product use. Specifically, respondents were asked the following: 1) "During the past 30 days, on how many days did you smoke cigarettes? " and 2) "During the past 30 days, on how many days did you smoke cigars, cigarillos, or little cigars?" Response options for the two questions ranged from 0-30 days. Due to the highly skewed nature of the frequency of use variables, respondents were categorized into four mutually exclusive use groups: 1) exclusive e-cigarette users (ie, did not smoke combustible cigarettes or cigars in the past 30 days); 2) dual e-cigarette and cigarette users (ie, smoked combustible cigarettes, but not cigars in the past 30 days); 3) dual e-cigarette and cigar users (ie, smoked cigars, but not combustible cigarettes in the past 30 days); and 4) poly users of e-cigarettes, cigarettes, and cigars (ie, smoked combustible cigarettes and cigars in the past 30 days).

It is important to assess dualtobacco use of e-cigarettes and cigars separately from dualtobacco use of e-cigarettes and combustible cigarettes due to differences in the sizes, fillers, flavors, constituents (eg, nicotine and carcinogens), and topography patterns of combustible cigars compared to combustible cigarettes. [12] [13] [14] However, the sample size of the dual e-cigarette and cigar use group in the current study was relatively small (n=35), which was anticipated due to the relatively lower cigar smoking prevalence of about 4% compared to the combustible cigarette smoking prevalence of about 8% among U.S. 18-24-year-olds. 10 In order to test if statistical results were sensitive to the grouping of participants, a sensitivity analysis was performed combining the dualtobacco use groups into one group, resulting in three mutually exclusive use groups: 1) exclusive e-cigarette users (ie, did not smoke combustible cigarettes or cigars in the past 30 days); 2) dual ecigarette and combustible cigarette or cigar users (ie, smoked either combustible cigarettes or cigars, but did not smoke both combustible cigarettes and cigars in the past 30 days); and 3) poly users of e-cigarettes, combustible cigarettes, and cigars (ie, smoked combustible cigarettes and cigars in the past 30 days).

COVID-19 outcomes. Respondents reported whether they were currently experiencing COVID-19 symptoms (eg, cough, fever or chills, difficulty breathing, fatigue, muscle ache, headache, new loss of taste or smell, nasal congestion, sore throat, nausea or vomiting, and diarrhea). Symptoms were those outlined specifically by the Centers for Disease Control and Prevention. 15 Students endorsing ≥1 symptom were categorized as having COVID-19 symptomatology. Students also reported whether they had been tested for COVID-19. Those tested were subsequently asked whether they had positive or negative diagnoses. Student demographics and other information-including age, sex, race/ethnicity (non-Hispanic White, Black, Other/Multiracial, and Hispanic), sexual orientation (heterosexual, lesbian, gay, bisexual, transgender, and questioning (LGBTQ)), university site, current fraternity/sorority membership status, and current residence (off-campus housing, campus residence hall, other university housing, and parent's home)-were also assessed.

Multivariable logistic regression models compared differences in the likelihood of reporting COVID-19 symptomatology, testing, and prior positive diagnosis by the four mutually exclusive polytobacco use groups. All models controlled for student age, sex, race/ethnicity, sexual orientation, university site, fraternity/sorority membership status, and residence. We tested the sensitivity of our main models' results by combining the two dualtobacco product use groups to assess three mutually exclusive groups (ie, exclusive e-cigarette use, dualtobacco use, and polytobacco use) and the covariates as the independent variables in three refitted multivariable logistic regression models for each of the three outcome variables of COVID-19 symptomatology, testing, and diagnosis. We report model fit statistics (ie, Hosmer and Lemeshow goodness-of-fit tests) and adjusted odds ratios (AORs) and 95% confidence intervals (CIs). Participants with missing data on COVID-19 symptoms (n=41, 5.1%), past 30-day tobacco use (n=5, 0.7%), and student covariates (n=5, 0.7%) were removed prior to analysis. Statistical analyses conducted using Stata SE version 16, 16 indicated no significance differences between those providing complete and missing data.

Among the 756 current e-cigarette users, the mean student age was 20.3 (SD=1.5) years; 49.6% (n=375) were female; 20.0% (n=151) were LGBTQ; and 61.6% (n=466) were non-Hispanic White, 15.5% (n=117) were Hispanic, 14.8% (n=112) were non-Hispanic Other/Multiracial, and 8.1% (n=61) were non-Hispanic Black (Table 1) . Approximately 25% (n=187) of students were current fraternity/sorority members, and the majority (57.9%; n=438) lived in offcampus housing.

Concerning current dual-and polytobacco use patterns among the four exclusive groups, 53.6% (n=405) were exclusive e-cigarette users, 20.4% (n=154) were dual e-cigarette LGBTQ includes asexual, bisexual, gay, lesbian, pansexual, queer, questioning, and same gender loving. and combustible cigarette users, 4.6% (n=35) were dual ecigarette and cigar users, and 21.4% (n=162) were poly users of e-cigarettes, combustible cigarettes, and cigars (see Table  1 ). Concerning the current dual-and polytobacco use patterns among the three exclusive groups for the sensitivity analysis, 53.6% (n=405) were exclusive e-cigarette users, 25.0% (n=189) were dual e-cigarette and combustible cigarette or cigar users, and 21.4% (n=162) were poly users of ecigarettes, combustible cigarettes, and cigars (Table 2 ).

Overall, 12.6% (n=95) of students reported currently experiencing COVID-19 symptomatology, with the top three symptoms being nasal congestion (34.7%, n=33), cough (30.5% n=29), and sore throat (29.5%, n=28). Respondents with current symptomatology reported an average of 2.3 (SD=1.5) symptoms. Most students (85.5%, n=646) reported COVID-19 testing, and of those, 16.7% (n=108) reported a positive COVID-19 diagnosis.

The main multivariable logistic regression model results are presented in Table 1 . The Hosmer and Lemeshow goodness-of-fit tests for the main models with COVID-19 symptomatology (P=0.359), testing (P=0.818), and diagnosis (P=0.549) as the outcomes were not significant, indicating good fit for all three models. Additionally, for all models, variance inflation factors (VIFs) ranged from 1.06-2.81 with mean VIFs of 1.34-1.37, indicating no multicollinearity in the models. The sensitivity multivariable logistic regression model results are presented in Table 2 . The Hosmer and Lemeshow goodness-of-fit tests for the sensitivity models with COVID-19 symptomatology (P=0.410), testing (P=0.781), and diagnosis (P=0.737) as the outcomes were also not significant, indicating good fit for all three models. Additionally, for all sensitivity models, variance inflation factors (VIFs) ranged from 1.09-2.81 with mean VIFs of 1.36-1.39, indicating no multicollinearity in the models.

For the main model findings, dual e-cigarette and combustible cigarette users (AOR=2.12, 95%CI=1.05-4.27) and poly users of e-cigarettes, combustible cigarettes, and cigars (AOR=3.70, 95%CI=1.78-7.70) were more likely to have current COVID-19 symptomatology, compared to exclusive ecigarette users (see Table 1 ). Older students, female students, those attending the university in Arkansas and Ohio, and who lived in on-campus housing other than a campus residence hall were significantly more likely to have COVID-19 symptomatology than younger students, male students, those attending the university in Texas, and who lived in off-campus housing, respectively. For the sensitivity model findings, dualtobacco users of e-cigarettes and combustible cigarettes or cigars were 2.19 times more likely (95%CI =1. 13-4.23) to report current COVID-19 symptomatology compared to exclusive e-cigarette users after covariate adjustment (see Table  2 ). Polytobacco users of e-cigarettes, combustible cigarettes, and cigars were 3.71 times more likely (95%CI =1.78-7.71) to report COVID-19 symptomatology than exclusive e-cigarette users. Similar to the main model covariate findings, older students (AOR=1.31, 95%CI=1.11-1.53, P=0.001), female students (AOR=1.85, 95%CI=1.09-3.13, P=0.023), those attending the universities in Arkansas (AOR=2.64, 95% CI=1.06-6.55, P=0.036) and Ohio (AOR=2.71, 95% CI=1.07-6.86, P=0.036), and who lived in on-campus housing other than a campus residence hall (AOR=2.29, 95%CI=1.05-5.03, P=0.038) were significantly more likely to have COVID-19 symptomatology than younger students, male students, those attending the university in Texas, and who lived in off-campus housing, respectively. While no differences were found between the four tobacco use groups based on COVID-19 testing in the main model, significant covariates included university site and residence location; students attending the universities in Arkansas and Indiana were at increased odds of being tested for COVID-19 than students attending the university in Texas, whereas those who lived with their parents were at reduced odds of being tested than students who lived in off-campus housing (see Table 1 ). No differences were found between the three tobacco use groups based on COVID-19 testing in the sensitivity model (see Table 2 ). Similar to the main model findings, participants attending the universities in Arkansas (AOR=6.40, 95%CI=2.31-17.74, P<0.001) and Indiana (AOR=5.71, 95%CI=2.82-11.57, P<0.001) were at increased odds of being tested for COVID-19, and participants who lived with their parents (AOR=0.43, 95%CI=0.20-0.93, P=0.031) were at reduced odds of being tested than students attending the university in Texas and who lived in off-campus housing, respectively.

When compared with exclusive e-cigarette users, polytobacco users were 2.16 times more likely (95%CI=1. 11-4.20) to have a positive COVID-19 diagnosis. Concerning significant covariates, students who were female, non-Hispanic Other/Multiracial, and attending the university in Arkansas were at reduced odds of having a prior positive COVID-19 diagnosis than students who were male, non-Hispanic White, and attending the university in Texas (see Table 1 ). Additionally, fraternity/sorority members were at increased odds of having a prior positive COVID-19 diagnosis than students who were not fraternity/sorority members. Similarly, in the sensitivity model, polytobacco users were significantly more likely (AOR=2. 16, to have a prior positive COVID-19 diagnosis than exclusive e-cigarette users (see Table 2 ). Similar to the main model findings, students who were female (AOR=0.54, 95%CI=0.34-0.86, P=0.010), non-Hispanic Other/Multiracial (AOR=0.40, 95%CI=0.19-0.84, P=0.015), and attending the university in Arkansas (AOR=0.22, 95%CI=0.09-0.56, P=0.002) were at reduced odds of having a COVID-19 diagnosis compared to students who were male, non-Hispanic White, and attending the university in Texas. Fraternity/sorority members (AOR=1.90, 95%CI=1.15-3.14, P=0.012) were at increased odds of having a COVID-19 diagnosis compared to students who were not fraternity/sorority members (see Table 1 ).

Overall, findings from this investigation assert that compared to college student exclusive e-cigarette users, college student e-cigarette users who concurrently engage in polytobacco use with combustible cigarettes and cigars were at increased risk of having COVID-19 symptomatology and having received a prior positive diagnosis. No differences were found between current tobacco use groups and COVID-19 testing, which was expected due to similar random COVID-19 testing programs at all four universities during the fall academic semester. Further, dual e-cigarette and combustible cigarette users exhibited more than two times the odds of reporting current COVID-19 symptomatology compared to exclusive ecigarette users. Our findings align with prior research among a U.S. sample of adults documenting current exclusive e-cigarette users had reduced odds of reporting respiratory symptoms compared to dual users. 17 It is noteworthy that dual e-cigarette and cigar users were also at over two-fold increased odds of having COVID-19 symptomatology and diagnosis, although not statistically significant likely due to the small group size. Thus, sensitivity results combining dualtobacco use groups revealed that dualtobacco users of e-cigarettes and combustible cigarettes or cigars were at significantly two-fold odds of reporting COVID-19 symptomatology. A prior review reports tobacco use may increase COVID-19 infection risk via alteration of the immune and oxidative stress responses and adverse respiratory and cardiovascular effects. 18 Additionally, e-cigarette use and combustible tobacco use impair endothelial function, which is an early marker of cardiovascular disease and may contribute to increased COVID-19 symptomatology and severe health consequences. 19 Thus, tobacco use can lead to increased cardiopulmonary risk due to increased risk of both infection and more severe COVID-19 outcomes. 20 Due to the increased risk of nicotine dependence, it is concerning that about 1-in-5 college student e-cigarette users in the current study were polytobacco users, though this is consistent with prior national estimates noting a 21% prevalence rate of polytobacco use. 21 Longitudinal evidence suggests the majority of e-cigarette users are also polytobacco users, and that polytobacco users are at decreased likelihood of quitting tobacco use 2-3 years later compared with exclusive e-cigarette users. 22 Moreover, polytobacco users may be at higher risk of having a prior positive COVID-19 diagnosis due to vaping/smoking behavior involving higher finger-to-lip contact and sharing devices, as these behaviors can increase the modes of transmission of SARS-CoV-2 (ie, contact or droplet, fomite). 23 Future research should consider measuring these behavioral aspects of tobacco product use that may place polytobacco users at increased susceptibility of COVID-19 diagnosis. Additionally, we found female students were more likely to report COVID-19 symptomatology, but less likely to report a prior positive COVID-19 diagnosis when compared to male students. This parallels documented sex-based disparities in which males have higher COVID-19 incidence and severity than females, likely due to varying genetics and sex hormones, as well as a higher prevalence of comorbidities and poor health behaviors including tobacco use among males. 24 Specifically, polytobacco use risk is higher in male young adults than that of female young adults. 21 

The findings of this investigation should be considered in unison with several limitations. First, although we included students at four geographically diverse U.S. locations, the data are not nationally generalizable. Second, while COVID-19 testing programs and course format offerings were similar at each of the four university campuses, we did not collect data on whether students were completing their courses in-person, online, or via a hybrid format during the fall semester. We did not have information available on COVID-19 testing rates at each campus. Specifically, university sites may have differed based on students' likelihood of being tested for COVID-19, irrespective of tobacco use, due to the number of tests randomly administered during the fall semester, which may have varied based on test availability and accessibility both on-campus and off-campus (eg, pharmacy). Third, we were unable to quantify tobacco product use behaviors (eg, number of hand-to-mouth instances) or other preventive health behaviors (eg, handwashing) that may place college student e-cigarette users at greater risk for COVID-19 infection risk. Fourth, we were unable to assess biochemically measured tobacco use (eg, cotinine) or confirm COVID-19 outcomes via medical record review due to the anonymous survey nature. Fifth, since all participants currently used e-cigarettes, we did not have a nontobacco use comparison group. Finally, we administered the survey crosssectionally and were unable to assess relationships over time.

Notwithstanding the limitations noted, this investigation suggests polytobacco use could increase the risk of COVID-19 symptomatology and diagnosis among college student e-cigarette users. Since the concurrent use of two or more tobacco products increased COVID-19-related risks, our results underscore the need to strengthen programming geared to prevent and combat college student e-cigarette and polytobacco use.

What is already known on this topic?

Tobacco use is a potential risk factor for COVID-19 symptoms and infection among youth and young adults. A research gap remains on dual-and polytobacco use and COVID-19 outcomes among college student electronic cigarette (e-cigarette) users.

College student polytobacco users of e-cigarettes, combustible cigarettes, and cigars are at increased risk of COVID-19 symptomatology and diagnosis compared to college student exclusive e-cigarette users. College student dualtobacco users are also at increased risk of COVID-19 symptomatology compared to exclusive e-cigarette users.

What are the implications for health promotion practice or research?

Implementing university-based programming to reduce dualand polytobacco use of e-cigarettes with combustible tobacco products may have the potential to reduce COVID-19 symptomatology and infection.

Dr. Merianos conceptualized and designed the study, carried out the analysis and interpretation of the data, drafted the manuscript, and approved the final manuscript as submitted. Dr. Russell conceptualized and designed the study, revised the manuscript for important intellectual content, and approved the final manuscript as submitted. Dr. Mahabee-Gittens conceptualized and designed the study, drafted the manuscript, and approved the final manuscript as submitted. Dr. Barry conceptualized and designed the study, revised the manuscript for important intellectual content, and approved the final manuscript as submitted.

Meng Yang conceptualized and designed the study, revised the manuscript for important intellectual content, and approved the final manuscript as submitted. Dr. Lin conceptualized and designed the study, interpreted the data, revised the manuscript for important intellectual content, and approved the final manuscript as submitted.

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported in part by the National Institute on Drug Abuse (Grant Number K01DA044313) and National Institute of Environmental Health Sciences (Grants Number R21ES032161, R01ES030743, R01ES027815) of the National Institutes of Health. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

The University of Cincinnati (IRB#: 2020-0717), University of Arkansas (IRB#: #2007273054), Texas A&M University (IRB#: 2020-0160), and Indiana University (IRB#: 2004149119) provided approval for all study procedures. Participants provided written informed consent by acknowledging the research information sheet before proceeding to the survey.

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