Effects of E-cigarettes on Combustible Cigarette Smoking Among Adults With Opioid Use Disorder on Buprenorphine: Single Arm ERASER Pilot Trial

Introduction: People with opioid use disorder (OUD) on buprenorphine smoke at high rates and have low cessation rates, even with evidence-based medications. Electronic cigarettes (EC) are a promising harm reduction strategy for combusted cigarette (CC) smokers unable to quit. Unfortunately, people with OUD are underrepresented in EC research. Aims and Methods: A pilot study assessed the feasibility, acceptability, and preliminary effectiveness of EC as a harm reduction tool among CC smokers with OUD on buprenorphine (N = 30). Participants were provided with an EC and freebase nicotine liquid (6 mg/mL) with a choice of flavor and a brief training session. Research visits were scheduled in person at baseline, week 4, and week 8 (follow-up). Daily diary assessments were completed during the 4-week EC period. Results: Most visits (>74%) and 61.4% of daily diary assessments were completed. During the 4-week study period, 90% of participants used the EC at least one day, 66.7% used the EC for at least 16 days, and 43.3% used the EC every day. Significant reductions were observed between baseline and both weeks 4 and 8 in cigarettes smoked per day (CPD_baseline = 16.2[8.3], CPD_{week4 =} 9.6[9.3], CPD_week8= 8.4[8.3]) carbon monoxide (CO) levels (CO_baseline = 21.5[15.0], CO_{week4 =} 16.9[9.6], CO_{week8 =} 15.7[10.0]), and nicotine dependence measured using the Fagerström Test for Nicotine Dependence (FTND_baseline = 5.4[2.5], FTND_week4 = 4.2[2.6], FTND_week8 = 4.4[2.6]), with all p-values < .05. Conclusions: Implementing an EC protocol in outpatient maintenance treatment programs is feasible and acceptable. Preliminary results suggest that ECs may facilitate reductions in cigarettes per day, CO levels, and nicotine dependence. Future research should explore the effect of prolonged EC use on harm reduction and cessation milestones.