CHANGE in Cigarette, other tobacco product, and cannabis use among individuals who used or did not use CANNABIS during a smoking cessation trial.

Abstract

Introduction: As many as 40% of adults who smoke (AWS) use cannabis, yet little is known about how cigarette-cannabis (CIG-CAN) use impacts change in cigarette and other tobacco product (OTP) use during a quit attempt.

Methods: Secondary data analysis of a smoking cessation randomized clinical trial (RCT) that enrolled 392 Black adults who wanted to quit cigarettes and were provided 18 weeks of standard or adapted pharmacotherapy. Participants self-reported cigarettes, cannabis, and OTP at W0,2,6,12,18, and 26. Longitudinal modeling of group, time, and group by time effects compared change in cigarettes, cannabis, and OTP between those who did and did not use cannabis.

Results: Nearly half (47.2%,185/392) were CIG-CAN users. Cannabis types were joints (78.4%) and blunts (51.9%). Significant reduction in CPD over time (p=0.02) did not differ by group (p=0.18). OTP had significant group, group by time interaction and time effect (p<0.001), however, OTP use is small and had minimal effect on consumption. CIG-CAN increased cannabis use through week 26 (p<0.001). When CPD decreased, there was a compensatory effect on OTP (<.0001), but not cannabis (p=0.37).

Conclusion: Prevalence of cannabis use was high among Black adults attempting to quit cigarette smoking in an RCT. OTP use was minimal, but CIG-CAN maintained higher OTP and increased consumption of cannabis while having similar reductions in CPD. Findings require replication in a prospectively designed study but suggest a pattern of compensation, primarily with cannabis, among CIG-CAN that may limit potential health benefit of cigarette reduction and could compromise future attempts at cessation.

Implications: This study's findings suggest a large percentage of cannabis use (47%) and within those users an increase of other tobacco products. At the same time, participants reduced cigarettes per day in both those who did and did not use cannabis. These findings reinforce the need for targeted treatment of all combustible products. Clinical practice guidelines and empirically informed interventions to address CIG-CAN co-use are absent in the field and urgently needed. In addition, better assessment of CIG-CAN in clinical studies is needed to aid in understanding the health impact of co-use.