Abstract
Background
Marijuana and tobacco co-use is highly prevalent among African American young adults. In an effort to inform prevention and treatment interventions, the current study examined the expectancies around the co-use of marijuana and cigarettes among African American young adults.
Methods
An anonymous online survey recruited African American adults (N = 111) age 18 to 29 who reported past-month marijuana and cigarette co-use. Participants completed the 14-item Nicotine and Marijuana Interaction Expectancy (NAMIE) Questionnaire, with three scales: (1) marijuana use increases tobacco use and urges, (2) tobacco use increases marijuana use and urges and (3) smoking to cope with marijuana urges. Participants also answered questions about marijuana and tobacco initiation and use. Analyses were conducted separately for blunt co-users (i.e., blunt and cigarette use) and non-blunt co-users (i.e., non-blunt marijuana and cigarette use).
Results
A majority of co-users (66%) used blunts as a form of co-use. Non-blunt co-users had higher expectancy scores on NAMIE scales 2 and 3 than blunt co-users. However, only blunt co-users showed a positive association between severity of marijuana use and NAMIE scales 2 (p <.01) and 3 (p <.01).
Conclusions
Findings provide further evidence for the use of the NAMIE and suggest a need to assess and address expectations regarding marijuana and tobacco co-use in prevention and treatment interventions, especially among young African American adults who co-use blunts and cigarettes.
Keywords: marijuana, tobacco, marijuana and tobacco co-use, African Americans, young adults, expectancies
Co-occurring marijuana and tobacco use have been associated with increased rates of psychiatric disorders and psychosocial problems (Peters et al., 2014). Further, co-use has been linked to more days of past month marijuana use and higher rates of marijuana dependence relative to marijuana only smokers (Peters et al., 2012; Ream et al., 2008; Timberlake, 2009). Despite the negative health related consequences of tobacco and marijuana co-use, a recent review found only three studies focusing on co-use prevention and two studies on treatment (Ramo et al., 2012). Since that review, a few treatment studies for marijuana and tobacco co-use have been published (Becker et al., 2014; Lee et al., 2015). However, additional research is needed to inform the effective development of prevention and treatment interventions for tobacco and marijuana co-users.
Identifying interaction expectancies (i.e., the effects that an individual anticipates from their use of two substances) might help identify barriers and strategies that should be used in the development of prevention and treatment interventions for co-users (Rohsenow et al., 2005). High expectations may pose barriers to cessation of either substance, therefore underlying low motivation to quit. The Nicotine and Other Substance Use Interaction Expectancies Questionnaire (NOSIE) was developed by Rohsenow et al. (2005) to investigate expectations regarding the relationship between smoking and other substance use held by treatment-seeking substance users. Participants reported that substance use almost always increased their smoking or urges to smoke, but smoking only increased their substance use or urges about half of the time (Rohsenow et al). More recently, Ramo et al. (2013) adapted the NOSIE to examine cigarette and marijuana interaction expectancies (Nicotine and Marijuana Interaction Expectancy [NAMIE] questionnaire). In a non-treatment seeking sample of young adult marijuana and tobacco co-users, Ramo et al. found that young adults who used more tobacco and marijuana held higher expectancies regarding the interaction of the two substances. In addition, days of past month marijuana use and thoughts about abstinence, significantly predicted responses to the NAMIE scales.
The current study examines presence and predictors of tobacco and marijuana interaction expectancies among African American young adults participating in an anonymous online survey. African Americans were chosen as the population of interest, as co-use is considerably high among this population of young adults (Montgomery, 2015) and they experience higher rates of negative drug-related consequences of substance use comparable to other racial/ethnic groups (Boyd et al., 2006; Zapolski et al., 2014). Further, African Americans are more likely to smoke blunts (i.e., hollowed out cigars or cigarillos that are filled with marijuana) than other racial/ethnic groups (Koopman Gonzalez, Cofie, & Trapl, 2015; Montgomery, 2015; Sinclair, Foushee, Pevear et al., 2012), and little is known about whether this form of co-use may be associated with unique patterns of interaction expectancies compared to other forms of co-use. The purpose of the current study was to (1) determine if there are differences in tobacco and marijuana co-use expectations among blunt and cigarette co-users [hereafter referred to as blunt co-users] and non-blunt and cigarette co-users [non-blunt co-users] and (2) determine if expectancies among blunt co-users and non-blunt co-users were associated with variables that have been linked with expectations about drug use in previous studies (Harty et al., 2015; Hendricks et al., 2011; Ramo et al., 2012; Skenderian et al., 2008), including age at first tobacco use, age at first marijuana use, days of past month marijuana use, and days of past month tobacco use.
2. Materials and Methods
2.1 Participants and Procedures
Participants were African American young adults who completed an anonymous online survey. The survey was designed to assess patterns of and factors associated with marijuana and tobacco co-use among non-treatment seeking young adults. Participants were recruited via flyers distributed in predominately African American communities (e.g., businesses, churches, barbershops, and community health resources centers), word of mouth, and a free campaign on Craigslist in a Midwestern city in the United States. The survey link, along with a Quick Response (QR) code, was included on the flyer, which directed participants to the consent form, screening questions, and a secure survey within Qualtrics.
Participants who met the following criteria were eligible to participate in the survey: (1) were between the ages of 18–29, (2) self-reported as being a non-Hispanic African American or Black woman or man, (3) self-reported smoking marijuana (e.g., blunts, joints) at least four times in the past month, (4) self-reported smoking tobacco (e.g., cigarettes, cigars) at least 20 of the past 30 days, (5) were not enrolled in outpatient or residential substance abuse treatment for marijuana or not engaged in formal smoking cessation treatment (e.g., medication, counseling) in the past year and (6) had a personal email account to receive an electronic gift card. Eligible participants were invited to complete a brief (approximately 15 minutes) survey, and received a $20 online gift card for their time and effort.
Of the 185 participants who completed the survey screener, 162 participants (87.6%) met eligibility criteria to complete the survey. Of those, 144 (88.9%) completed the survey. For the current study, we used data from participants who reported past month marijuana and cigarette use (N = 111). Computer IP addresses were tracked in the study. If the respondent’s computer indicated that the survey had already been completed, the Qualtrics system would not allow the participant to regain access to the survey. Participants’ contact information (e.g., email addresses) was stored in a separate file unlinked to survey responses and destroyed immediately following the study. Identifiable research information was protected by a Certificate of Confidentiality from the National Institutes of Health. All materials and procedures were approved by the Institutional Review Board at the University of Cincinnati.
2.2 Measures
The Nicotine and Marijuana Interaction Expectancy (NAIME) questionnaire is a 14-item measure (Ramo et al., 2012) designed to examine client’s perceptions of the interaction between cigarettes and marijuana. Participants rated each of the items on a Likert scale ranging from 1 (never) to 5 (always). The NAMIE includes three scales: (1) the effects of marijuana use on cigarette smoking (e.g., “I need a cigarette while I am using marijuana”); (2) the effects of cigarette use on marijuana smoking (e.g., “Smoking gives me more desire for marijuana”); and (3) smoking cigarettes to cope with urges to use marijuana (e.g., “I smoke to take the edge off when I am feeling a desire for marijuana”). Participants’ tobacco and marijuana history and use were assessed using items from the National Survey on Drug Use and Health (NSDUH, 2012). Tobacco use measures included age of first tobacco use, days of past month tobacco use, type of cigarettes smoked (i.e., menthol vs. non-menthol) and use of other tobacco products (e.g., hookah, e-cigarettes). Marijuana use measures included age of first use, days of past month marijuana use and days of past month blunt use. Participants who reported past month blunt use and cigarette use were categorized as “blunt co-users”, while participants who reported cigarette use but no past month blunt use were categorized as “non-blunt co-users.” The survey also assessed past month use of other drugs, including cocaine, opioids, and alcohol.
2.3 Data Analysis
Descriptive statistics and Cronbach’s alpha coefficients were estimated to characterize the sample and examine the reliability of the NAMIE subscales among African American young adults. Six multiple regression models examined the relationship between each of three NAMIE subscales and marijuana use and initiation (i.e., days of past month marijuana use and age at first use) and tobacco use and initiation (i.e., days of past month tobacco use and age at first use) To control for multiple comparisons but allow for meaningful patterns to emerge from the data, significance level was set at .01.
3. Results
3.1 Sample Characteristics
The sample was mostly male (86.5%) and had an average age of 23.7 (SD = 2.1). Most participants were college graduates (61%) and had full-time jobs (78%). Approximately 49% of the sample reported legal trouble. Cigars, cigarillos, and little cigars (68%) were the second most popular tobacco product used in the past month following cigarettes (100%). Participants also reported smoking menthol cigarettes (87.2%) and drinking alcohol (31%) in the past month. The majority of the sample also reported smoking blunts in the past year (95%), and in the past month (66%). In the month preceding the study, participants reported smoking marijuana for an average of 12.6 (SD = 11.1) days and tobacco for an average of 20.4 (SD = 5.8) days. As shown in Table 1, relative to non-blunt co-users, blunt co-users were more likely to have some college experience or be a college graduate and reported drinking alcohol in the past month. Subsequent analyses controlled for education level and other past month alcohol/drug use.
Table 1.
Demographic and substance use characteristics of African American young adult marijuana and cigarette co-usesrs (N = 111)
| Non-blunt and cigarette co-users (n = 34) | Blunt and cigarette co-users (n = 77) | Analyses | ||
|---|---|---|---|---|
|
| ||||
| Characteristic | % | % | X 2 | p |
| Gender | 4.68 | 0.04 | ||
| Female | 97.1 | 81.8 | ||
| Male | 2.9 | 18.2 | ||
| Education Level | 14.44 | <.01 | ||
| Did not graduate high school | 0 | 3.9 | ||
| High school graduate or GED | 0 | 15.6 | ||
| Some college | 11.8 | 28.6 | ||
| College graduate | 85.3 | 50.6 | ||
| Postgraduate degree | 26.1 | 1.3 | ||
| Employment | 4.33 | 0.36 | ||
| Full-time | 85.3 | 75.3 | ||
| Part-time | 14.7 | 13 | ||
| Student | 0 | 5.2 | ||
| Unemployed | 0 | 5.2 | ||
| Other | 0 | 1.3 | ||
| Legal Trouble (Ever) | 0.05 | 0.84 | ||
| Yes | 47.1 | 49.4 | ||
| No | 52.9 | 50.6 | ||
| Cigarette Brand | 0.07 | 0.72 | ||
| Menthol | 87.3 | 88.9 | ||
| Non-Menthol | 12.7 | 11.1 | ||
| Other past month drug use | ||||
| Cocaine | 11.7 | 11.7 | 20.24 | <.01 |
| Opioids | 7.2 | 4.5 | ||
| Alcohol | 3.6 | 32.4 | ||
| Other past month tobacco use | ||||
| Cigars, cigarillos and little cigars | 55.9 | 73.2 | 5.67 | 0.03 |
| Smokeless tobacco (chew, dip, snuff) | 1.2 | 4.2 | ||
| Pipe | 5.2 | 7.8 | ||
| Electronic cigarettes | 41.3 | 39.6 | ||
| Hookah | 9.2 | 10.3 | ||
|
| ||||
| M (SD) | M (SD) | F | p | |
|
| ||||
| Age | 23.1 (2.5) | 24.2 (2.3) | 2.94 | 0.12 |
| Days of past month tobacco use | 20.5 (4.1) | 20.3 (6.5) | 0.01 | 0.93 |
| Age at first tobacco use | 17.6 (2.0) | 16.7 (2.5) | 3.27 | 0.07 |
| Days of past month marijuana use | 8.26 (7.9) | 14.5 (11.8) | 7.82 | <.01 |
| Age at first marijuana use | 16.9 (1.7) | 17.1 (2.4) | 0.17 | 0.68 |
3.2 NAMIE Scale Scores and Predictors
The NAMIE subscales scores were internally consistent, with coefficient alphas of .91, .77 and .93 on scales 1 (marijuana increases tobacco use and urges), 2 (tobacco increases marijuana use and urges) and 3 (smoking to cope with marijuana urges), respectively. The interscale correlations between the three subscales were moderate (ranged from .46 to .63). The average scores for all African American young adults in the sample was 3.21 (SD = 0.63), 3.03 (SD = 0.64) and 3.05 (SD = 0.71) on NAMIE scales 1, 2 and 3, respectively. Blunt co-users (M = 3.28, SD = 0.73) and non-blunt co-users (M = 3.19, SD = 0.28) had similar scores on scale 1 of the NAMIE, F(1,110) = 2.44, p = 0.12. Compared to blunt co-users, non-blunt co-users had higher scores on scale 2 (M = 3.27 [0.41] vs. 2.92 [0.71]; F(1, 110) = 7.47, p < .01) and scale 3 (M = 3.31 [0.32] vs. 2.94 [0.80]; F(1,110) = 6.83, p < .01).
Among non-blunt co-users, age of first marijuana use, age at first tobacco use, marijuana use and tobacco use were not significantly associated with co-use expectations (Table 2). However, days of past month marijuana use were positively associated with co-use expectations on NAMIE scale 2 (B = 0.02, p < .01) and 3 (B = 0.04, p < .01) among blunt co-users. Age of first marijuana use, age at first tobacco use and past month tobacco use were not associated with co-use expectations among blunt co-users.
Table 2.
Predictors of Nicotine and Marijuana Interaction Expectancy Questionnaire Scales among African American Young Adult Marijuana and Cigarette Co-Users (N = 111)
| Non-Blunt Marijuana and Cigarette Co-Users | Blunt and Cigarette Co-Users | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| ||||||||||||
| NAMIE Scales | B | SE(B) | β | p | Model R2 | Model p | B | SE(B) | β | p | Model R2 | Model p |
| (1) Marijuana increases tobacco use and urges | 0.13 | 0.41 | 0.02 | 0.23 | ||||||||
| Days of past month marijuana use | −0.01 | 0.00 | −0.06 | 0.73 | −0.17 | 0.01 | −0.28 | 0.04 | ||||
| Days of past month tobacco use | −0.01 | 0.01 | −0.01 | 0.95 | 0.03 | 0.02 | 0.03 | 0.85 | ||||
| Age at first marijuana use | −0.09 | 0.05 | −0.55 | 0.06 | −0.03 | 0.04 | −0.09 | 0.39 | ||||
| Age at first tobacco use use | 0.05 | 0.04 | 0.34 | 0.24 | 0.01 | 0.03 | 0.03 | 0.82 | ||||
| (2) Tobacco increases marijuana use and urges | 0.10 | 0.53 | 0.09 | <.01 | ||||||||
| Days of past month marijuana use | −0.01 | 0.01 | −0.28 | 0.13 | 0.02 | 0.01 | −0.36 | <.01 | ||||
| Days of past month tobacco use | −0.02 | 0.02 | −0.16 | 0.38 | −0.02 | 0.14 | −0.03 | 0.89 | ||||
| Age at first marijuana use | 0.00 | 0.07 | −0.01 | 0.99 | −0.01 | 0.03 | −0.02 | 0.83 | ||||
| Age at first tobacco use | −0.01 | 0.06 | −0.06 | 0.83 | 0.03 | 0.03 | 0.12 | 0.27 | ||||
| (3) Smoking to cope with marijuana urges | 0.45 | 0.04 | 0.32 | <.01 | ||||||||
| Days of past month marijuana use | −0.02 | 0.01 | −0.59 | 0.05 | −0.04 | 0.01 | −0.59 | <.01 | ||||
| Days of past month tobacco use | −0.02 | 0.01 | −0.19 | 0.18 | 0.02 | 0.01 | 0.12 | 0.27 | ||||
| Age at first marijuana use | 0.04 | 0.04 | 0.19 | 0.40 | 0.03 | 0.03 | 0.1 | 0.30 | ||||
| Age at first tobacco use | 0.04 | 0.04 | 0.03 | 0.91 | 0.04 | 0.03 | 0.11 | 0.27 | ||||
4. Discussion
The current study examined the interaction expectancies of African American young adults who reported marijuana (blunt and non-blunt) and cigarette use in the past month. Expectations regarding the interaction of marijuana and tobacco as measured by the NAMIE showed strong internal consistency, supporting use of this measure in the African-American population. Reliability compares to that among a predominately White sample of marijuana and tobacco co-users participating in a national online survey (Ramo et al., 2012); however mean scores were relatively higher in the current study compared to the Ramo et al study on all three NAMIE scales. It is unclear whether the scores are statistically different across groups. This could not have been accounted for solely by the extent of blunt use in this African-American sample, as scores were higher for non-blunt co-users in the current study as well. More work is needed to clarify ethnic differences in interactions expectancies more fully.
African American young adults reported the highest rating on scale 1 (marijuana use increases tobacco use and urges), which might partially explain why tobacco initiation often follows marijuana use among African American young adults (reverse gateway; Guerra et al., 2000; White et al., 2007). Longitudinal research is needed to examine the relationship between co-use expectations and marijuana and tobacco initiation among African American young adults.
Relative to blunt co-users, non-blunt co-users were more likely to report that smoking cigarettes increased their marijuana use and urges and that smoking cigarettes helps them to cope with their marijuana use and urges. Blunt smokers are exposed to nicotine when preparing blunts with the outer wraps of cigars and cigarillos (Peters, Schauer, Rosenberry, & Pickworth, 2016), while non-blunt marijuana users (e.g., joint smokers) are not exposed to nicotine in the same way. Non-blunt co-users might lean more heavily on cigarettes for exposure to nicotine and therefore may be more likely to believe that cigarettes have a more powerful role in the interaction between marijuana and tobacco. It might follow that non-blunt co-users would smoke more cigarettes than blunt co-users, however, findings here do not support that notion. It is important to note that all of the participants in this sample reported 20 or more days of past month tobacco use, and 87.2% reported smoking menthol cigarettes in the past month, consistent with other African-American smoking samples (Alexander, Trinidad, Sakuma et al., 2016). Additional research with a wide range of light and heavy menthol and non-menthol cigarette smokers is needed.
Notably, we found that days of past-month marijuana use were associated with co-use expectations among blunt co-users but not among other co-users. This could indicate that the NAMIE is a better assessment tool for blunt co-users than non-blunt co-users, or that substituting tobacco for marijuana and vice-versa is equally common among non-blunt co-users of all levels. Research with larger samples is needed to clarify this further.
In addition to a small sample size, there are a few other limitations that should be noted. First, the cross-sectional design of the study prevents causal interpretation of the findings. Second, the sample is mostly male and may not be generalizable to a more diverse sample of African American young adults. The study relied on self-reported, anonymous data; however, the targeted recruitment method (e.g., posting flyers in predominately African American communities, discussing the inclusion/exclusion criteria with potential participants in the community) increases the validity of the data. Despite these limitations, the current findings highlight preliminary evidence for the significant relationship between drug use outcomes and co-use expectancies among African American young adults that has important research and clinical implications.
Our findings highlight the extent to which tobacco and marijuana use can perpetuate use of the other substance, and the importance of treatments targeting thoughts and expectations about the interaction of these two substances. Understanding the relationship between marijuana and tobacco will increase the effectiveness of existing interventions and facilitate the development of new interventions that target cognitions related to co-use among African American young adults, especially among individuals who co-use cigarettes and blunts.
Acknowledgments
Research reported in this publication was supported by the National Institute on Drug Abuse of the National Institutes of Health (NIH) under Award Number R25DA035163. The writing of this article was supported by K23DA032578. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
Contributor Information
LaTrice Montgomery, Assistant Professor, Addiction Sciences Division, University of Cincinnati College of Medicine, Department of Psychiatry & Behavioral Neuroscience, 3131 Harvey Avenue, Suite 104, Cincinnati, OH 45229
Danielle Ramo, Assistant Professor in Residence, University of California, San Francisco, Department of Psychiatry & Langley Porter Psychiatric Institute, Weill Institute for Neurosciences, Helen Diller Comprehensive Cancer Center, 530 Parnassus Avenue, San Francisco, CA 94143
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