Since our study examined proportions of nicotine and cannabis vaping among adults who currently used EVPs, it is difficult to compare our results directly to other studies that examine nicotine and cannabis vaping separately at the population level. Nevertheless, our results indicate that an association may exist where adults with lower education have lower odds of vaping nicotine and cannabis, relative to vaping nicotine only, compared to adults with higher education, or that adults with higher education vape a mix of nicotine and cannabis relative to adults with lower education. Cannabis smoking is associated with tobacco cessation difficulty, tobacco use relapse, and increased intensity of tobacco use . If cannabis vaping has a similar effect, it may undermine cessation efforts for adults who use EVPs. The reverse gateway theory posits that cannabis use may encourage tobacco use, especially if routes of administration are similar. However, drivers of cannabis vaping initiation among those who vape nicotine might differ from drivers of nicotine vaping initiation among those who vape cannabis . Adults who use both nicotine and cannabis have reported the heightened subjective effects of cannabis from simultaneous nicotine and cannabis vaping as a primary reason behind co-use .
The extent to which simultaneous nicotine and cannabis vaping varies from simultaneous nicotine and cannabis smoking among adults is not fully understood. Further research is needed to better understand the intersection between cannabis vaping and cannabis smoking, including how mode of cannabis consumption might impact tobacco use outcomes . Nevertheless, grow cannabis the neurobiological effects of cannabis vaping or smoking can complicate the advancement of tobacco regulatory science and may promote nicotine vaping. In 2009, the FDA was granted regulatory authority over tobacco products in the US but does not have direct power over cannabis constituents in e-liquids . Understanding nicotine and cannabis vaping patterns is vital to inform tobacco control researchers of the potential implications related to tobacco regulation and cessation efforts. We acknowledge limitations of our study findings. First, due to how the cannabis vaping measures were assessed in the PATH Study , it is possible that we missed additional exclusive cannabis vapers in this analysis. In addition, this pattern of assessment may be prone to having adults contradict themselves, such as indicating that they ever vape cannabis but “never” in terms of how frequently they vape the substance, making it difficult to infer which use groups they belong to. Second, it difficult to measure the frequency and intensity by which specific substances are consumed in the PATH Study .
While respondents were asked about how often they vaped cannabis when using EVPs, we were unable to quantify frequency of cannabis vaping . Third, cannabis vaping was examined in the context of ever use only, and respondents who currently used EVPs endorsed cannabis vaping may have only vaped cannabis in some period that preceded the past 30 days. Fourth, we simplified the nicotine and cannabis vaping groups in terms of how often they vaped both substances . Nevertheless,indoor cannabis grow system our non-nicotine-exclusive vaping categories represent varying vaping use patterns with important regulatory and health implications. Fifth, nicotine/cannabis vaping categories relied on self-reports and did not include biochemical verification for all respondents . Sixth, due to limited sample sizes, we had to aggregate American Indian/Alaska Native, Asian, and multiracial adults into an NH Other category, and lesbian, gay, and bisexual adults into an LGB+ category.
We were additionally unable to disaggregate Hispanic ethnic identity with the present data, which may mask important differences for ethnic subgroups such as Mexican Americans or Puerto Ricans. Finally, data were collected from late 2016 to early 2018, and results from this study may not represent more recent use patterns, particularly in light of the COVID-19 pandemic. Despite these limitations, our findings demonstrate that the proportion of nicotine and cannabis vaping differs across adult socio-demographic groups, calling for additional work that aims to unveil and address these use disparities. With cannabis vaping on the rise among younger populations , efforts aimed at reducing nicotine and cannabis consumption overall and within high-risk groups are needed, especially those that address vaping as an additional route of administration. Our study also examines patterns of nicotine and cannabis vaping, with important variation by how adults vape each substance. These results are presented compared to adults who vape only nicotine to capture differences by use groups that are less of a focus in the substance use literature, particularly the tobacco control literature.