Participant CESD scores were not associated with frequency of marijuana use or cigarette use

Two hundred adolescents were consented into the study and completed the baseline visit. Of those, 28 denied smoking cigarettes in the past 30 days and 7 declined to answer the question about marijuana use and were thus excluded from the analysis. The resulting sample had a mean age of 16.1 years and was racially diverse, with 28% participants identifying as White, 19% African American, 19% Hispanic and 34% other. Participants averaged 3.01 CPD for a duration of 1.98 years . Fifty-one participants reported daily cigarette smoking and 111 reported non-daily smoking . Mean scores were 2.56 on the mFTQ , 4.52 on the HONC , -1.75 on the NDSS , and 10.13 on the ICD-10 . Most participants reported marijuana use in the past 30 days with 43 using weekly, and 62 reporting daily use. Frequency of marijuana use was correlated with CPD , but not with the frequency of alcohol use .In general linear models controlling for age, years of smoking, and daily versus non-daily smoking, frequency of marijuana use was significantly and positively associated with nicotine addiction . The findings were consistent across all four measures of dependence and remained significant for the mFTQ after removing the question on CPD. When examining the NDSS sub-scales, only the drive and priority sub-scales were significantly associated with marijuana frequency. Older age, more years smoking, and daily smoking were associated with greater nicotine dependence in all models. The total percent of variance predicted ranged from 25% for the HONC to 44% for the mFTQ and NDSS. Illicit drug use may co-occur across substances,cannabis growing equipment and follow-up analyses sought to examine whether the finding of an association with nicotine dependence was specific to marijuana.

Therefore, we also assessed co-use with other illicit substances. In the past 3 months, 40 participants reported ecstasy use. A small number of participants reported use of cocaine/crack , methamphetamine , mushrooms/ mescaline , heroin , Percocet/Vicodin , or LSD , preventing inclusion in analyses. Ecstasy, included as a covariate in the fully adjusted general linear models, was not a significant contributor with p-values ranging from .24-.99 and the effects for marijuana remained largely unchanged. Marijuana smoking was prevalent in this adolescent sample of tobacco smokers: 80% reported past month marijuana use and more than a third smoked marijuana daily. Notably, among adolescent tobacco smokers who also smoked marijuana, the frequency of marijuana use was associated with greater levels of nicotine addiction on all three major scales used in studies with adolescents plus the ICD-10. Moreover, models incorporating age, frequency and years of tobacco smoking with marijuana accounted for 25-44% of variance in adolescent nicotine dependence. Interestingly, CPD was only minimally associated with the frequency of marijuana use and made minimal contribution to the model since associations with the mFTQ were similar after removing the question about CPD.The finding that with the exception of drive and priority, the other sub-scales of the NDSS were not significantly associated with marijuana frequency was not surprising since most of these adolescent smokers were light and intermittent tobacco users and dimensions of dependence such as stereotypy and tolerance become more prominent as teens develop more regular and established patterns of smoking . However, despite relatively light tobacco use, the drive sub-scale, which measures the compulsion to smoke, and the priority sub-scale, which measures the preference of smoking over other reinforcers, were associated with marijuana use. It is possible that since both marijuana and tobacco share common pathways of use, smoking cues for one substance may trigger craving for the other, and thus reinforce patterns of use. As such, tobacco and marijuana may serve as reciprocal reinforcers.

Some limitations of this brief include the relatively small sample size and the lack of detailed information on the timing of the initiation of marijuana use with regard to cigarette smoking. Future studies will need to examine how the proximity of marijuana use to cigarette smoking affects the degree of nicotine addiction. For example, examining whether concomitant use impacts the level of nicotine addiction more than smoking marijuana separately from tobacco. The sample largely consisted of light smokers, which reflects adolescent smoking in the US. That we found such a strong association between marijuana use and nicotine addiction in this group of relatively light tobacco smokers is notable, and reinforces the relevance of the association. Recreational marijuana commercialization is gaining momentum in the US. Among the 11 states and Washington DC that have legalized recreational marijuana since 2012, retail markets have been opened or anticipated in 10 states, where over a quarter of the US population live. The presence of recreational marijuana dispensaries increased rapidly following the commercialization. Children are at a high risk of initiating marijuana use and developing adverse consequences related to marijuana. The rapidly evolving environment poses considerable concerns about children’s exposure to marijuana and related marketing and creates significant challenges for pediatricians preventing, treating, and educating about marijuana related harms among children. As stated in its most recent policy statement about marijuana commercialization, the American Academy of Pediatrics “strongly recommends strict enforcement of rules and regulations that limit access and marketing and advertising to youth”. The presence of RMDs in neighborhoods and point-of-sale marketing such as advertising and promotional activities in RMDs might increase the visibility and awareness of marijuana products among children, whose perceptions and behaviors may be influenced. A study in Oregon found that dispensary storefront was the most common source of advertising seen after commercialization. 

Self-reported exposure to medical marijuana advertising was found to be related to higher levels of use and intentions of future use among children in California schools. Products, packages, and advertisements that are designed to be appealing to children are particularly concerning. Tobacco and alcohol literature repeatedly suggested that children are common targets of marketing. Despite the fact that all the states with marijuana commercialization have some form of prohibitions on child-appealing products and marketing, it remains undocumented as to what extent the marijuana industry is complying. This study is the first to comprehensively assess point-of-sale marketing practices in RMDs with a focus on those relevant to children. Unlike previous marijuana research relying on individual self-reported exposure measures, we adopted the direct and objective observation approach that has been commonly used in tobacco and alcohol studies on retail outlets. We audited RMDs near a representative and large sample of schools in California, the largest legal retail market in the US where over 10 million children can be potentially influenced. We identified product and packaging characteristics, advertising and promotional activities,cannabis grow table and access restrictions in these dispensaries. Six trained field workers audited retail environments in RMDs in closest proximity to the 333 schools . We first identified dispensaries using crowd sourced online websites, including Weedmaps, Wheresweed, Leafly, and Yelp. State licensing records were not used because they could not provide a complete list of dispensaries at the time of data collection. Specifically, 1) Marijuana commercialization in California took effect in January 2018. During the study period, California was in a transition stage when annual licenses were just issued, and most were not approved. 2) The licensing policy in California was not enforced, with a large portion of dispensaries operating without licenses. 3) For licensed dispensaries, the registered and actual business name and address often mismatched. Alternatively, we utilized crowd sourced databases, which were considered as reliable, up-to date, and comprehensive sources of dispensary directories. To identify the dispensary closest to a school, field workers entered school zip code in the online searchable databases. The street addresses of all the dispensaries with the school zip code were geocoded and mapped in ArcGIS to compute their distances to the school. Field workers then called the dispensary with the shortest distance to verify its address and operational status. These procedures were repeated if a dispensary was permanently closed or not verifiable via multiple calls until an active dispensary was identified. The primary focus was RMDs. Yet, medical marijuana dispensaries that require a doctors’ recommendation or state patient ID cards coexisted in California in 2018. During call verifications, if dispensary staff indicated that a doctors’ recommendation or a patient ID was required to enter the dispensary and make purchase, the dispensary was categorized as a MMD.i Fieldworkers also verified dispensary classification during the subsequent auditing. For those verified as MMDs, we repeated the aforementioned procedures until an active RMD was identified.

The six trained workers in teams of two audited verified RMDs.ii On average, each RMD visit took 10-15 minutes. The 103 RMDs had unique RMD-school pairs and the 60 RMDs were the closest ones to two or more schools out of the remaining 230 schools. In the main analysis, we reported observations in the unique RMDs . In the secondary analysis, we reported observations on RMDs using school as the unit of analysis . The 60 RMDs shared by two or more schools were counted multiple times or over-weighted in the secondary analysis, reflecting their potential to influence children in multiple schools. The Human Research Protections Program at the University of California San Diego deemed this research non-human-subject and required no review. We validated SMDA-CF through a pilot test on 18 RMDs in California. To calculate inter-rater reliability, two workers in a team independently audited the same dispensaries. Reliability analysis indicated moderate to high reliability for SMDA-CF as a whole . Because of the concerns about some low-reliability items, in the formal field work of auditing 163 RMDs, the two workers in a team audited dispensaries together and discussed to resolve discrepancies before submitting observations. This study demonstrated that, in the early stage of marijuana commercialization in California, point-of-sale marketing practices that are appealing to children were minimal on the exterior of the RMDs around schools. However, such practices were abundant on the interior. Marketing practices not specifically appealing to children were common on both the interior and exterior of the RMDs. Given the age limit, RMDs’ exterior marketing might be the most concerning source of exposure for children. It is reassuring that child-appealing marketing was rarely observed on the exterior of the RMDs around schools. Yet, three quarters of the RMDs had some form of child appealing marketing on the interior, which violated the California laws. Although children should have little direct access to the interior, child-appealing items may be available to children through indirect pathways and should not be overlooked. For instance, children’s social networks such as older relatives, peers, or caregivers are their important sources of drugs. A study reported that almost three quarters of underage users obtained marijuana from friends, relatives, or family members. Child-appealing products, paraphernalia, or promotional materials could then be made available to children through these adults who are eligible for marijuana purchase. Particularly, about 30% RMDs violated the California law to offer free samples, which could be taken out of the dispensaries and given away to children. These child-appealing items in RMDs could be also resold to children in illicit markets by street dealers. Research on tobacco and alcohol have suggested that children are exposed to and influenced by tobacco and alcohol products and point-of-sale marketing despite the age limit for purchase . Whether and how the marketing activities inside of RMDs impact children’s perceptions and behaviors should be examined in future research. Meanwhile, exterior retail environments not specifically relevant to children still warrant further attention. For instance, 63% RMDs had image or wording indicative of marijuana on the exterior. One third of the RMDs had generic advertisements, and some advertisements were of a relatively big size. Marijuana could be smelled outside of 25% RMDs. All of these might potentially increase perceived presence of RMDs in the neighborhoods and shape children’s social norms. Approximately half of schools had RMDs located within a 3-mile distance that is reachable to children by walking, cycling, or driving. Some RMDs were located further away, especially in suburban or rural areas. Nonetheless, children are not free from exposure to RMDs even if RMDs are located more than 3 miles away from schools. In 2009, the average travel distance from home to school among all school children was 4.4 miles; among high school students, the average distance was even longer .