Abstract
Background:
Tobacco use is high among marijuana and tobacco users, compared to tobacco-only users. This study examined the relative ranking (based on prevalence) of past 30-day tobacco product use separately across young adult and older adult past 30-day marijuana and tobacco co-users and tobacco-only users.
Method:
Prevalence and relative ranking of past 30-day use of eight different tobacco products and blunts were examined in young adult (ages 18–24) and adults (ages 25+) tobacco users who did and did not report past 30-day marijuana use (unweighted n=33,644) from Wave 4 of the Population Assessment of Tobacco and Health study. Multiple logistic regressions examined increased odds of using each product in the past 30-days by marijuana and tobacco co-use.
Results:
Nearly half (47.9%) of past 30-day young adult tobacco users reported past 30-day marijuana use (e.g., co-use); 27.7% of adult tobacco users reported past 30-day co-use. Cigarettes were the most popular product used in the past 30-days across tobacco-only and co-users of both age groups. Rankings of all other tobacco products differed between the age groups. Among young adult co-users, blunts were ranked the second most popular product used in the past 30-days, followed by e-cigarettes, and then cigarillos/filtered cigars. Among adult co-users, blunts were ranked the fourth most popular product used in the past 30-days. Adult co-users reported significantly higher prevalence of past 30-day use of all combustible products compared to tobacco only users.
Conclusions:
Co-users may be at increased risk of health consequences given high rates of combustible tobacco use.
Keywords: marijuana, co-use, tobacco, blunts, e-cigarettes, cigars, combustible tobacco, young adults
1. Introduction
The co-use of marijuana with tobacco has increased in the last decade, and is common among young adults (ages 18 to 24) relative to any other age group (Azofeifa, 2016; Cohn, Abudayyeh, Perreras, & Peters, 2019; Schauer, Berg, Kegler, Donovan, & Windle, 2015a). Tobacco use is particularly high among marijuana and tobacco co-users. Data from the 2003 to 2012 National Survey of Drug Use and Health (NSDUH) showed that 68% of past month marijuana users reported past month tobacco use, compared to just 25% of non-past month marijuana users (Schauer et al., 2015a). The co-use of marijuana with tobacco is associated with a variety of negative consequences, including greater marijuana and nicotine dependence (Patton et al., 2002; Ream, Benoit, Johnson, & Dunlap, 2008; Strong et al., 2018; Weinberger et al., 2018), poor tobacco cessation and marijuana outcomes (Botchway & Deshpande, 2015; Moore & Budney, 2001; Strong et al., 2018), co-occurring alcohol and other drug use, and depression and anxiety (Crane, Langenecker, & Mermelstein, 2015; Gage et al., 2015; J. S. Tucker et al., 2019). Co-use has also been linked to a variety of physical health harms, including firsthand and secondhand smoke or vape exposure (American NonSmokers’ Rights Foundation, 2020; Schauer, Tynan, & Marynak, 2020), increased exposure to toxicants and potential cancer-causing agents that arise from combusted product use (Klupinski et al., 2016; Klupinski et al., 2020; Moir et al., 2008; Sheehan, Hamnett, Beasley, & Fitzmaurice, 2019; Wei et al., 2016), and e-cigarette and vaping related lung injury (EVALI) largely driven by vitamin e acetate in THC oils being used in vaping devices (Blount et al., 2020).
The prevalence of alternative tobacco products in the U.S., like hookah, e-cigarettes, and little cigars/cigarillos has been on the rise (Cornelius, Wang, Jamal, Loretan, & Neff, 2020; Kasza et al., 2017). This is concerning, as many of these products can be used as vehicles to consume marijuana (Cooper & Haney, 2009; Hughes et al., 2014; Malouff, Rooke, & Copeland, 2014; Rabin & George, 2015; Ream et al., 2008; Seaman, Stanton, Edwards, & Halenar, 2020; J. Tucker, Vuchinich, Black, & Rippens, 2006). Cigarettes are one of the most commonly used tobacco products among marijuana users. For example, data from the NSDUH show that 60% of past-month marijuana users report current cigarette smoking (Schauer, Berg, Kegler, Donovan, & Windle, 2015b), and results from Wave 1 of the Population Assessment of Tobacco and Health (PATH) study show that 30% of current cigarette smokers report past year marijuana use (Conway et al., 2017). Of note, a recent study using 10 years of data from the National Health and Nutrition Examination Survey (NHANES), but focused only on young adults, found that the co-use of marijuana with cigarettes in this age group remained stable over time, despite overall declines in cigarette smoking in the general population (Jamal et al., 2015). Combining marijuana and tobacco together in a cigar product, known as blunt smoking, is also increasingly popular, particularly among young adults and is associated with mental health problems, greater nicotine dependence, and substance use problems (Cohn, Johnson, Ehlke, & Villanti, 2016; Schauer et al., 2015b; Seaman et al., 2020). Marijuana concentrates such as THC liquids, oils, or waxes can be vaporized in devices that are similar to electronic nicotine delivery systems (ENDS or e-cigarettes), wherein the concentrate or flower is heated but not burned or combusted (e.g., marijuana vaping). Recent estimates from the Monitoring the Future Study show that the prevalence of marijuana vaping has increased significantly from 2017 to 2019 among young adults, with 22% of young adults reporting past year marijuana vaping in 2019, a 6% increase from 2017 (Schulenberg et al., 2020). Lastly, the co-use of marijuana with hookah/shisha/waterpipe has received growing attention in surveillance studies, but less is known about this form of co-use. One study from Wave 1 of the PATH survey (collected 2013 and 2014), found that 51.7% of adult (ages 18 and older) past year hookah users reported past year marijuana use, compared to just 10% of non-hookah users (Conway et al., 2017). Using Wave 2 of the PATH study, Cohn et al found that 32% of young adult marijuana and tobacco co-users reported using hookah in the past 30-days. Taken together, heterogeneity exists in the prevalence of individual tobacco product use with marijuana use.
The literature has predominantly examined differences between co-users and non-users or co-users and tobacco-only users on combustible tobacco use as a broad combined category, or focused on co-use with cigarettes or cigars (e.g., in the form of blunts). However, given the evolving tobacco marketplace, additional descriptive epidemiologic data on the prevalence of individual tobacco product use (such as e-cigarette, hookah, and noncombustible tobacco products) is warranted across tobacco users who do and do not engage in marijuana use. Using U.S. national data from Wave 4 of the PATH study, this study examined, in young adult (ages 18–24) and adult (ages 25+) past 30-day tobacco-only users and past 30-day marijuana and tobacco co-users: 1) the prevalence of individual tobacco product use (e.g., cigarettes, e-cigarettes, large cigars, little cigars, etc.) in the past 30-days; the 2) relative ranking (based on prevalence of use) of individual tobacco product use across past 30-days across tobacco-only and co-users; and 3) the association of marijuana and tobacco co-use (vs tobacco-only use) with increased odds of reporting past 30-day use of each individual tobacco product. Because past month marijuana use is two times higher in young adults than the national average among adults (23% vs 11.9%, respectively) (Substance Abuse and Mental Health Services Administration & Center for Behavioral Health Statistics and Quality, 2019), and given the high rates of marijuana and tobacco co-use in young adults, we used an approach similar to several other published studies using PATH data (Cohn et al., 2018; Villanti et al., 2017), wherein we examined differences across young adults (ages 18–24) and adults (ages 25). Information about tobacco product prevalence rankings would help determine which tobacco products are most popular and could be targeted in public health messaging campaigns.
2. Materials and Methods
2.1. Sample
Data are from the adult Wave 4 (2017 to 2018) Public Use File (PUF) of the PATH Study, a nationally representative, longitudinal cohort study of US adults 18 years and older. PATH Wave 4 included n = 11,195 young adults ages 18 to 24 and 22,444 adults ages 25 and older. Recruitment involved address-based, area-probability sampling using an in-person household screener. African Americans, adult tobacco users, and individuals aged 18–24 were oversampled. The weighting procedures adjusted for oversampling and nonresponse, yielding representative estimates of the non-institutionalized, civilian U.S. population. Details regarding the PATH Study design and methods have been published (Hyland et al., 2016) and can be found at https://www.icpsr.umich.edu/icpsrweb/ICPSR/studies/36498
The analytic sample for the present study consisted of n = 15,185 (unweighted) adults ages 18 and older who reported using at least one tobacco product in the past 30-days (cigarettes, e-cigarettes, traditional cigars, cigarillos/filtered cigars, hookah, pipe tobacco, smokeless tobacco, snus). The PATH survey included detailed descriptions and photos of traditional cigars, cigarillos, and filtered cigars to aid in responding. Traditional cigars were described as “contain[ing] tightly rolled tobacco that is wrapped in a tobacco leaf. Some common brands of cigars include Macanudo, Romeo y Julieta, Arturo Fuente, and Cohiba, but there are many others.” Cigarillos and filtered cigars were described as: “Cigarillos and filtered cigars are smaller than traditional cigars. They are usually brown. Some are the same size as cigarettes, and some come with tips or filters. Some common brands are Black & Mild, Swisher Sweet, Dutch Masters, Phillies Blunts, and Winchester.”
2.2. Measures
Demographic variables included age (18–24, 25–34, 35–44, 45–54, 55–64, 65+), gender, race/ethnicity (White, non-Hispanic; Black, non-Hispanic; Other, non-Hispanic; Hispanic), education (less than high school, high school graduate or GED, some college or higher), and income (less than $10k, $10k–$24,999, $25k–$49,999, $50k–$99,999, $100k+). A continuous variable for age is not included in the PUF data file; it is coded as categorical.
Past 30-day marijuana use (yes/no) was queried as use of “marijuana, marijuana concentrates, marijuana waxes, THC, or hash oils”. Dichotomous (yes/no) assessment of past 30-day use of each of eight different tobacco products (cigarettes, e-cigarettes, traditional cigars, cigarillos/filtered cigars, hookah, pipe tobacco, smokeless tobacco, snus), as well as past 30-day blunt use was included in analyses. While blunt use is a specific form of marijuana and tobacco co-use, a cigar is used for blunt smoking and thus it was included in our definition of a tobacco product. Further, published work indicates that misclassification of blunts (e.g., not reporting blunt smoking as marijuana use, or not reporting blunt smoking as tobacco use) can occur (Cohn et al., 2016; Delnevo, Bover-Manderski, & Hrywna, 2011; Delnevo & Hrywna, 2007; Delnevo, Hrywna, Giovenco, Lo, & O’connor, 2017). Thus, it may be possible that individuals who endorse no past 30-day use of marijuana may endorse past 30-day use of blunts. Past 30-day marijuana vaping (e.g., electronic nicotine product use with marijuana) and past 30-day hookah smoking with marijuana were not queried in Wave 4 of PATH. Number of days consumed marijuana or each of the individual tobacco products in the past 30-days are not included in the PUF.
2.3. Statistical Analyses
Weighted cross-tabulations examined the prevalence and demographic correlates in the full sample of past 30-day tobacco users and differences across co-users and tobacco-only users. Co-use was defined as reporting use of marijuana in the past 30-days and use of at least one of the eight tobacco products in the past 30-days. Next weighted cross-tabulations examined the relative ranking and differences in the prevalence of each of the different tobacco products, as well as blunts (total of nine products assessed), across co-users and tobacco-only users, separately for each age group (young adults ages 18–24 and older adults ages 25+). A relative ranking for each tobacco product was obtained by first sorting the prevalence of past 30-day use for each tobacco product and blunts in descending order (from highest to lowest), separately for the co-users and tobacco-only users, and then assigning a numeric value (e.g., 1–9) to each product based on its use prevalence relative to the other products. Thus, the product with the highest prevalence in a group was ranked as 1, the product with the second highest prevalence in a group was ranked 2, etc. Rao Scott chi-square tests were used to estimate significant differences in individual tobacco product prevalence between groups with significance at p<0.05.
Next, separate weighted multiple logistic regression models examined the associations between past 30-day marijuana and tobacco co-use (compared to past 30-day tobacco-only use) with increased odds using of each of the eight tobacco products and blunts in the past 30-days (reference: no past 30-day use of that product), controlling for demographics. Tobacco products were not mutually exclusive.
For all study variables, responses of “don’t know” and “refused” were treated as missing. Analyses were conducted using SVY procedures in Stata/MP version 14.1 and Surveyfreq and Surveylogistic procedures in SAS version 9.4 to account for weighting. Confidence intervals were estimated using the balanced repeated replication method.
3. Results
3.1. Sample Characteristics: Overall and by co-use group
Table 1 shows sample characteristics among past 30-day tobacco users overall and separately across past 30-day marijuana and tobacco co-users and past 30-day tobacco-only users. Overall, about half of the analytic sample of past 30-day tobacco users were aged 18 to 34; and the majority were male, White, endorsed some college education or higher, and had an income of less than $50,000 per year. One third of the total sample of past 30-day tobacco users reported marijuana use in the past 30-days (33.09%). Co-users and tobacco-only users differed significantly by age, race/ethnicity, education, and household income. Specifically, compared to tobacco-only users, co-users had a higher proportion of respondents who were young adults (ages 18–24), Black (non-Hispanic), reporting some college education or higher, and income of $24,999 or less.
Table 1.
Demographic characteristics of adult tobacco-only users and marijuana and tobacco co-users from Wave 4 of the PATH survey
| Past 30-day Tobacco Users | ||||
|---|---|---|---|---|
| Total Sample of past 30-day tobacco user Weighted % = 46.44 (45.46, 47.42) | Past 30-day co-users* Weighted % = 33.09 (31.81, 34.38) | Past 30-day tobacco- only users Weighted % = 66.91 (65.61, 68.18) | p-value | |
| Unweighted n | 15185 | 5025 | 10160 | |
| Weighted % (95% CI) | Weighted % (95% CI) | Weighted % (95% CI) | ||
| Age | <.0001 | |||
| 18–24 | 28.93 (27.73, 30.16) | 41.95 (39.97, 43.96) | 22.49 (21.22, 23.81) | |
| 25–34 | 23.48 (22.40, 24.60) | 26.05 (24.22, 27.96) | 22.21 (20.92, 23.57) | |
| 35–44 | 15.03 (13.90, 16.24) | 13.46 (11.75, 15.37) | 15.81 (14.52, 17.19) | |
| 45–54 | 13.90 (13.10, 14.73) | 9.87 (8.59, 11.32) | 15.89 (14.86, 16.98) | |
| 55–64 | 12.30 (11.51, 13.13) | 7.01 (6.00, 8.18) | 14.91 (13.92, 15.95) | |
| 65+ | 6.36 (5.77, 6.96) | 1.66 (1.04, 2.56) | 8.69 (7.89, 9.51) | |
| Gender | 0.1249 | |||
| Male | 54.84 (53.62, 56.05) | 56.27 (53.96, 58.56) | 54.13 (52.68, 55.57) | |
| Female | 45.16 (43.94, 46.37) | 43.73 (41.43, 46.03) | 45.87 (44.42, 47.31) | |
| Race/Ethnicity | <.0001 | |||
| White (non-Hispanic) | 60.35 (59.10, 61.59) | 56.67 (54.51, 58.80) | 62.18 (60.62, 63.71) | |
| Black (non-Hispanic) | 15.18 (14.38, 16.02) | 17.96 (16.54, 19.47) | 13.81 (12.96, 14.70) | |
| Other (non-Hispanic) | 7.87 (7.24, 8.55) | 8.65 (7.57, 9.87) | 7.49 (6.73, 8.33) | |
| Hispanic | 16.60 (15.52, 17.68) | 16.72 (15.12, 18.41) | 16.52 (15.20, 17.91) | |
| Education | 0.0045 | |||
| < High school | 15.63 (14.74, 16.57) | 13.88 (12.47, 15.42) | 16.50 (15.33, 17.74) | |
| High school graduate or GED | 34.43 (33.42, 35.45) | 33.72 (31.94, 35.55) | 34.78 (33.47, 36.12) | |
| Some college or higher | 49.94 (48.60, 51.25) | 52.40 (50.19, 54.58) | 48.72 (47.20, 50.21) | |
| Household income | <.0001 | |||
| < $10k | 21.52 (20.49, 22.58) | 23.53 (21.80, 25.36) | 20.51 (19.39, 21.67) | |
| $10,000 to $24,999 | 24.57 (23.49, 25.69) | 27.64 (25.66, 29.71) | 23.04 (21.79, 24.35) | |
| $25,000 to $49,999 | 23.14 (22.00, 24.33) | 21.49 (19.77, 23.33) | 23.97 (22.59, 25.40) | |
| $50,000 to $99,999 | 19.66 (18.71, 20.66) | 16.16 (14.93 17.48) | 21.41 (20.03, 22.86) | |
| > $100k | 11.08 (10.27, 11.94) | 11.18 (9.89, 12.53) | 11.07 (10.14, 12.02) | |
Note. P-value based on Rao-Scott Chi-Square Test.
Co-use was defined as reporting use of marijuana in the past 30-days and use of at least one nicotine/tobacco product in the past 30-days.
3.2. Prevalence and rankings of past 30-day use of individual tobacco products among young adults
Table 2 shows the prevalence and relative ranking of past 30-day use of eight different tobacco products and blunts among young adult past 30-day co-users and tobacco-only users. Nearly half (47.97%) of young adult current tobacco users report co-use of tobacco with marijuana in the past 30-days. In terms of product popularity, cigarettes emerged as the most popular product compared to all other tobacco products and blunts. Further, the prevalence of past 30-day cigarette was equal across co-users and tobacco only users (59.27% for co-users vs 57.08% for tobacco-only users, ns). Blunts were the second most commonly used product in the past 30-days among the co-users, endorsed by 42% of co-users, followed by e-cigarettes (ranked #3), cigarillos/filtered cigars (ranked #4), and hookah (ranked #5). Among tobacco-only users, blunts were ranked as the eighth most commonly used tobacco product in the past 30-days. A small percent of tobacco-only users reported past 30-day blunt use (3.15%), even though they did not report past 30-day marijuana use. E-cigarettes were the second most popular product used by tobacco-only users, followed by cigarillos/filtered cigars (ranked #3), and then hookah (ranked #4).
Table 2.
Weighted population prevalence of individual tobacco product use among young adult past 30-day marijuana and tobacco co-users and past 30-day tobacco-only users, PATH Wave 4.
| Young Adults (ages 18–24) | |||||
|---|---|---|---|---|---|
| Pattern Popularity | Past 30-day Tobacco Users | ||||
| Co-Users | Tobacco-Only Users | Co-Users* 47.97% (weighted) | Tobacco-Only Users 52.03% (weighted) | P-Value | |
| Tobacco Product | |||||
| Cigarettes | 1 | 1 | 59.27% | 57.08% | 0.3230 |
| Blunt | 2 | 8 | 42.70% | 3.15% | <.0001 |
| E-cigarettes | 3 | 2 | 34.37% | 37.18% | 0.1744 |
| Cigarillos/Filtered cigars | 4 | 3 | 33.14% | 24.57% | <.0001 |
| Hookah | 5 | 4 | 13.07% | 15.62% | 0.1137 |
| Large/traditional cigars | 6 | 6 | 11.29% | 11.58% | 0.8644 |
| Smokeless | 7 | 5 | 8.46% | 13.80% | 0.0011 |
| Pipe | 8 | 9 | 3.10% | 2.76% | 0.6659 |
| Snus | 9 | 7 | 3.07% | 5.41% | 0.0147 |
Note. Items in bold are significantly different at p < .05. Pattern ranking based on weighted prevalence not on unweighted count.
Co-users defined as reporting use of marijuana in the past 30-days and use of at least one nicotine/tobacco product in the past 30-days (excluding blunts). Tobacco-only users defined as those who report using at least one nicotine/tobacco product (excluding blunts) in the past 30-days but who do not report using marijuana in the past 30-days.
Rao-Scott Chi-square tests showed that, relative to tobacco-only users, co-users reported significantly higher prevalence of past 30-day use of blunt (42.70% versus 3.15%) and past 30-day cigarillo/filtered cigar use (33.15% versus 24.57%), and significantly lower prevalence of smokeless (8.46% versus 13.80%) and snus tobacco use (3.07% versus 5.41%).
3.3. Prevalence and rankings of past 30-day use of individual tobacco products among adults ages 25 and older
Table 3 shows the prevalence and relative rankings of past 30-day use of eight different tobacco products and blunts among older adult (ages 25+) past 30-day co-users and tobacco-only users. Just under a third (27.07%) of adult past 30-day tobacco users reported co-use in the past 30-days. Tobacco product rankings differed across tobacco-only and co-users, with the exception of cigarettes. Cigarettes emerged as the most popular tobacco product across both groups (ranked #1), and the prevalence of past 30-day use was equivalent across co-users and tobacco-only users (79.73% for co-users versus 79.59% for tobacco-only users, ns). Cigarillos/filtered cigarettes were ranked second most popular product used in the past 30-days among co-users, followed by e-cigarettes (ranked #3), blunts (ranked #4), and then large cigars (ranked #5). Among tobacco-only users, e-cigarettes were ranked the second most popular product used in the past 30-days, followed by cigarillos/filtered cigars (ranked #3), smokeless tobacco (ranked #4), and then traditional/large cigars (ranked #5). Blunts were ranked as the ninth most popular tobacco product among tobacco-only users used in the past 30-days, endorsed by <1% of tobacco only-users. With the exception of cigarettes and snus, co-users reported significantly higher prevalence of past 30-day use of all tobacco products and blunts assessed compared to the tobacco-only users (all p’s <. 001).
Table 3.
Weighted population prevalence and ranking of individual tobacco product use among adult (25+ years old) past 30-day marijuana and tobacco co-users and past 30-day tobacco-only users, PATH Wave 4.
| Adults (ages 25+) | |||||
|---|---|---|---|---|---|
| Pattern Popularity | Past 30-day Tobacco Users | ||||
| Co-Users | Tobacco-Only Users | Co-Users* 27.02% | Tobacco-Only Users 72.98% | P-Value | |
| Tobacco Product | |||||
| Cigarettes | 1 | 1 | 79.73% | 79.59% | 0.9266 |
| Cigarillos/Filtered cigars | 2 | 3 | 25.35% | 12.17% | <.0001 |
| E-cigarettes | 3 | 2 | 23.83% | 16.32% | <.0001 |
| Blunts | 4 | 9 | 22.44% | 0.43% | <.0001 |
| Large/traditional cigars | 5 | 5 | 13.50% | 9.33% | <.0001 |
| Hookah | 6 | 6 | 6.30% | 3.01% | <.0001 |
| Smokeless | 7 | 4 | 5.12% | 10.35% | <.0001 |
| Pipe | 8 | 8 | 4.05% | 1.83% | <.0001 |
| Snus | 9 | 7 | 2.59% | 2.94% | 0.5583 |
Note. Items in bold are significantly different at p < .05. Pattern ranking based on weighted prevalence not on unweighted count.
Co-users defined as reporting use of marijuana in the past 30-days and use of at least one nicotine/tobacco product in the past 30-days (excluding blunts). Tobacco-only users defined as those who report using at least one nicotine/tobacco product (excluding blunts) in the past 30-days but who do not report using marijuana in the past 30-days.
3.4. Multiple logistic regression models of the association of past 30-day marijuana and tobacco co-use with individual tobacco product use
In adjusted models controlling for demographics, past 30-day marijuana and tobacco co-use (versus tobacco-only use) was associated with increased odds of reporting past 30-day use of cigarillos/filtered cigars (AOR = 1.93, 95% CI: 1.68, 1.44), e-cigarettes (AOR = 1.24, 95% CI: 1.03, 1.44), blunts (AOR = 38.25, 95% CI: 26.88, 54.45), large cigars (AOR = 1.25, 95% CI: 1.07, 1.46), and pipe (AOR = 1.62, 95% CI: 1.13, 2.31); and decreased odds of reporting past 30-day use of smokeless tobacco (AOR = 0.50, 95% CI: 0.39, 0.64) (all p’s < 0.05). There were no significant associations of past 30-day co-use (versus tobacco-only use) on past 30-day use of cigarettes, hookah, or snus. See Table 4.
Table 4.
Adjusted logistic regression models of the association of past 30-day cannabis and tobacco co-use with the odds of past 30-day use of each individual tobacco product, PATH Wave 4.
| Cigarettes (vs no past 30-day use) |
Cigarillos/ Filtered cigars (vs no past 30-day use) |
E-cigarettes (vs no past 30-day use) |
Blunts (vs no past 30-day use) |
Large cigars (vs no past 30-day use) |
Hookah (vs no past 30-day use) |
Smokeless (vs no past 30-day use) |
Pipe (vs no past 30-day use) |
Snus (vs no past 30-day use) |
|
|---|---|---|---|---|---|---|---|---|---|
| AOR [95% CI] |
AOR [95% CI] |
AOR [95% CI] |
AOR [95% CI] |
AOR [95% CI] |
AOR [95% CI] |
AOR [95% CI] |
AOR [95% CI] |
AOR [95% CI] |
|
| Cannabis and tobacco co-use status | |||||||||
| Co-User (n=4789) | 1.07 (0.93, 1.23) |
1.93
(1.68,2.21) |
1.24
(1.08,1.44) |
38.25
(26.88,54.45) |
1.25
(1.07,1.46) |
1.14 (0.93, 1.40) |
0.50
(0.39,0.64) |
1.62
(1.13,2.31) |
0.73 (0.53, 1.01) |
| Tobacco-only User (n=9572) | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Age | |||||||||
| 18–24 (n=4005) |
0.33
(0.29,0.37) |
1.94
(1.69,.21) |
2.31
(2.03,2.62) |
2.90
(2.35,3.57) |
1.04 (0.84, 1.29) |
3.83
(3.12,4.71) |
1.53
(1.22,1.92) |
1.01 (0.68, 1.51) |
1.56
(1.10,2.23) |
| 25+ (n=10356) | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Gender | |||||||||
| Female (n=6554) |
1.76
(1.56,1.99) |
0.66
(0.56,0.77) |
0.94 (0.84, 1.06) |
1.334
(1.07,1.67) |
0.27
(0.22,0.33) |
1.26
(1.01,1.58) |
0.08
(0.06,0.10) |
0.27
(0.18,0.42) |
0.15
(0.09,0.26) |
| Male (n=7807) | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Race/Ethnicity | |||||||||
| NH White (n=8578) | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| NH Black (n=2331) |
0.63
(0.54,0.77) |
3.05
(2.55,3.64) |
0.57
(0.47,0.70) |
2.91
(2.25,3.76) |
1.61
(1.31,1.98) |
2.83
(2.17,3.69) |
0.22
(0.17,0.30) |
0.48
(0.24,0.95) |
0.25 (0.14,0.46) |
| NH Other (n=1102) | 0.89 (0.72, 1.11) |
1.35
(1.04,1.75) |
1.07 (0.85, 1.36) |
1.54
(1.09,2.19) |
0.95 (0.68, 1.33) |
2.32
(1.60,3.35) |
0.71 (0.49, 1.02) |
1.11 (0.62, 1.98) |
0.48
(0.25,0.92) |
| Hispanic (n=2350) |
0.80
(0.67,0.96) |
1.32
(1.06,1.66) |
1.03 (0.87, 1.22) |
1.99
(1.52,2.61) |
0.98 (0.74, 1.30) |
3.64
(2.78,4.78) |
0.23
(0.17,0.33) |
0.95 (0.56, 1.61) |
0.40 (0.27,0.58) |
| Education | |||||||||
| < High school (n=2170) |
2.28
(1.88,2.76) |
1.14 (0.92,1.42) |
0.77
(0.63,0.94) |
0.91 (0.67,1.24) |
0.62
(0.45,0.85) |
0.42
(0.30,0.58) |
1.16 (0.84, 1.62) |
0.63 (0.37, 1.09) |
1.38 (0.89, 2.13) |
| High school graduate or GED (n=5036) |
1.62
(1.39,1.90) |
1.07 (0.92, 1.25) |
0.79
(0.69,0.90) |
0.95 (0.77, 1.18) |
0.65
(0.51,0.82) |
0.61
(0.48,0.77) |
1.42
(1.14,1.77) |
0.68 (0.46, 1.02) |
1.50
(1.09,2.07) |
| Some college or higher (n=7155) | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Household income | |||||||||
| < $10k (n=3106) |
2.64
(2.07,3.38) |
1.96
(1.51,2.56) |
0.86 (0.66, 1.13) |
0.94 (0.64, 1.40) |
0.65
(0.47,0.90) |
1.28 (0.84, 1.96) |
0.64
(0.45,0.92) |
2.84
(1.50,5.37) |
0.67 (0.41, 1.10) |
| $10,000 to $24,999 (n=3579) |
2.51
(2.05,3.09) |
1.50
(1.18,.90) |
0.90 (0.72, 1.13) |
1.03 (0.73, 1.45) |
0.52
(0.39,0.685 |
1.14 (0.75, 1.72) |
0.52
(0.37,0.72) |
1.58 (0.88, 2.83) |
0.48
(0.28,0.81) |
| $25,000 to $49,999 (n=3371) |
1.91
(1.56,2.33) |
1.307
(1.01,1.70) |
0.85 (0.69, 1.04) |
1.05 (0.773, 1.414) |
0.54
(0.42,0.70) |
1.05 (0.71, 1.54) |
0.71
(0.56,0.91) |
1.15 (0.66, 1.99) |
0.61
(0.38,0.99) |
| $50,000 to $99,999 (n=2785) | 1.15 (0.93, 1.43) |
0.97 (0.72, 1.30) |
0.91 (0.72, 1.17) |
1.15 (0.80, 1.65) |
0.59
(0.47,0.75) |
1.12 (0.78, 1.61 |
0.934 (0.68, 1.29) |
1.04 (0.54, 1.99) |
0.65 (0.42, 1.01) |
| > $100k (n=1520) | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
Note. Items in bold are significantly different at p < .05. Pattern ranking based on weighted prevalence not on unweighted count.
Co-users defined as reporting past 30-day marijuana use and at least one nicotine/tobacco product in the past 30-days (excluding blunts). Tobacco-only users defined as those who report using at least one nicotine/tobacco product (excluding blunts) in the past 30-days but who do not report using marijuana in the past 30-days. Reference category for each tobacco product was no use in the past 30-days.
4. Discussion
A third of past 30-day adult tobacco users report past 30-day marijuana use (e.g., co-use). Co-users were more likely to be Black, younger, and have lower income, similar to previously published U.S. population-based studies (Cohn et al., 2019; Schauer et al., 2015a; Seaman, Green, Wang, Quinn, & Fryer, 2019; Strong et al., 2018). Schauer and colleagues, who examined the overlap between tobacco use and marijuana use in 2003–2012 data from the National Survey of Drug Use and Health (NSDUH) reported that 17.8% of tobacco users reported past month marijuana use (Schauer et al., 2015a), and an analysis of Wave 1 PATH data (collected in 2013–2014) found that rates of current marijuana use varied by tobacco product use, ranging from 16.2% among cigarette-only users up to 33% among dual and poly-tobacco users (Strong et al., 2018). While it may seem that rates of co-use have increased over time in comparison to the NSDUH data, we caution such an interpretation as the NSDUH queried about fewer tobacco products than the PATH survey; and specifically did not ask about e-cigarette use. Finally, there were age group differences in the prevalence of co-use among tobacco users in our study. Nearly half of the young adult past 30-day tobacco users reported marijuana use the past 30-days, and while slightly less than a third of adult (ages 25+) past 30-day tobacco users reported past 30-day marijuana use.
In terms of product rankings, cigarettes were the most popular (based on prevalence of use) tobacco product used in the past 30-day among co-users of both age groups, endorsed by just over half of young adult co-users and nearly 80% of adult co-users. Beyond cigarettes, product rankings differed across age groups and co-use group. Consistent with previous work (Cohn et al., 2016; Schauer, Rosenberry, & Peters, 2017), blunts were popular among young adults and less popular among older adults. They were ranked the second most commonly used tobacco product in the past 30-days among young adult past 30-day tobacco and marijuana users, but only the fourth most popular product among older adult co-users. Relatedly, cigarillos/filtered cigars were the third most commonly used product among young adult co-users and second most commonly used among older adult co-users. It is possible that the relatively high prevalence of cigarillos/filtered cigars among co-users of both age groups (compared to other tobacco products) is because these products are being used to consume marijuana, such as in the form of a blunt, even though respondents do not perceive them as such. Relatedly, our findings showed that a small proportion of past 30-day tobacco-only users, across both age groups, reported past 30-day blunt use – a form of marijuana smoking - highlighting the issue of misclassification of cigars and blunts that has been cited in previous literature (Cohn et al., 2016; Delnevo et al., 2011; Nasim, Blank, Berry, & Eissenberg, 2012; Yerger, Pearson, & Malone, 2001). Lastly, e-cigarettes had a lower ranking (e.g., were less prevalent) than blunt smoking among young adult co-users, further reinforcing the need to focus attention on blunt smoking in this sub-group of adults.
Beyond rankings, the prevalence of past 30-day tobacco product use also differed between co-users and tobacco-only users, and by age group. Young adult co-users reported a significantly higher prevalence of past 30-day blunt smoking and cigarillo/filtered cigar use compared to young adult tobacco-only users, and a significantly lower prevalence of non-combustible tobacco product use (e.g., snus and smokeless tobacco use). In contrast, all types of combustible tobacco product use were more prevalent in adult co-users (ages 25+) compared to tobacco-only users, except for cigarettes. Furthermore, the prevalence of past 30-day e-cigarette use was significantly higher in adult co-users than adult tobacco-only users, while, in contrast, the prevalence of past-30-day e-cigarette use did not differ significantly across young adult co-users and tobacco-only users. This latter finding only further emphasizes the overall popularity of e-cigarette products among younger users, regardless of their marijuana use behavior.
Finally, in multiple logistic regression models controlling for demographics, co-users were significantly more likely to report past 30-day use of cigar products (cigarillos/filtered cigars and large cigars), blunts, e-cigarettes, and pipe relative to tobacco-only users; and significantly less likely to report smokeless tobacco use. Co-users compared to tobacco-only users were equally likely to report past 30-day use of cigarettes, hookah, and snus. The association of demographic factors with specific tobacco products showed substantial heterogeneity, underscoring the value of examining individual products separately, rather than in aggregate.
Our study has several strengths and implications that can be gleaned. First, our results add to the literature by examining the most recently available national data with a complete list of tobacco products; and then investigating the relative use rankings of these products by age group. Ranking was used as a metric to determine product popularity, wherein products with a higher past 30-day prevalence were considered more popular than others. This information can be used to help improve the targeting of messaging campaigns, but pinpointing tobacco products with the greatest use and thus importance. Second, a notable pattern emerged wherein adult co-users reported significantly higher rates of combustible tobacco use relative to adult tobacco-only users, raising concerns that the health consequences of co-using combusted tobacco with combusted marijuana could be amplified in this particular age group. Young adults did not show this same effect across co-users and tobacco-only users. Combustion of both a tobacco product and marijuana together may increase exposure to cancer-causing carcinogens and other toxicants than use of either product alone (Ream et al., 2008). This is particularly alarming because smoking marijuana use remains the preferred route of administration (Johnson et al., 2016; Russell, Rueda, Room, Tyndall, & Fischer, 2018), and cigarette smoking remains the most popular tobacco product used among marijuana users (Conway et al., 2017; Schauer et al., 2015b). Third, the relative popularity of blunt and cigar/cigarillo use among young adults observed in the data is quite concerning, as cigar smoking is associated with the similar negative health outcomes as cigarette smoking (Boffetta et al., 1999; Henningfield, Fant, Radzius, & Frost, 1999; Iribarren, Tekawa, Sidney, & Friedman, 1999). Results from our study can be used by stakeholders to design messaging strategies targeting different age groups of co-users and the harms associated with the tobacco products that are most prevalent among those groups. For example, messaging campaigns about the harms associated with co-use should consider targeting older adults, given the high rates of combustible tobacco use in this age group of co-users.
There are several limitations of this study. First, we were unable to examine past 30-day combined use of marijuana with e-cigarettes (e.g., marijuana vaping) or with hookah/shisha, as these questions were not asked in Wave 4 survey. Similarly, because the PATH public use survey data were used, age was only available as a categorical variable to protect possible disclosure of data. Second, we did not examine associations of product rankings with other indices of tobacco dependence or problematic use. Third, our analyses were cross-sectional and focused on only one period in time; not changes over time. Given the rapidly evolving tobacco and marijuana landscape, future work should examine how product rankings change over time, as more marijuana products become available to consumers, or as access to tobacco and marijuana products changes in response to new policies. Fourth, different modes of marijuana administration (e.g., edibles, lotions, waxes) were not assessed in the PATH survey. It would be important to examine the extent to which these newer, potentially less harmful forms of marijuana are correlated with individual tobacco product use. Finally, despite the oversampling strategies employed, certain vulnerable sub-groups (e.g., persons experiencing homelessness, active duty military, justice-involved persons) were excluded from the survey design.
5. Conclusions
Increases in the use of alternative tobacco products that are frequently co-used with marijuana is a public health concern. No study has captured the variation that exists in current tobacco product use among co-users and tobacco-only users by different age group and product type. Our analyses show a clear difference in tobacco product prevalence and preferences between co-users and tobacco-only users and by age group; with older adult co-users favoring combustible products, overall, and younger adult co-users favoring blunts and cigar products. Even after controlling for other factors, co-users were at increased odds of past 30-day use of most tobacco products available on the market. This information can be used to enhance the effectiveness of messaging programs at the local, state, and national level, targeting specific products and age groups.
Highlights.
A third of past 30-day tobacco users reported past 30-day marijuana use (co-use)
Nearly half of past 30-day young adult tobacco users reported past 30-day marijuana use
Cigarettes were the most popular tobacco product among co-users of marijuana and tobacco
Blunts were the second most popular product among young adult co-users
Combustible tobacco use was higher in adult co-users than tobacco-only users
Role of funding source:
This work was supported by the University of Oklahoma Health Sciences Center, Oklahoma Tobacco Settlement Endowment Trust (TSET) grant 092-016-0002 and NCI grant P30CA2255520 awarded to the Stephenson Cancer Center. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Footnotes
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CONFLICT OF INTEREST
No conflict declared.
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