Switching individuals in OUD treatment from cigarettes to the standardized research e-cigarette: A randomized waitlist-controlled cross-over trial.

INTRODUCTION: Most adults with opioid use disorder (OUD) smoke cigarettes, and cessation rates with FDA-approved medications are low. Switching to e-cigarettes (EC) is an effective cigarette reduction method in adults without OUD but has not been rigorously evaluated in adults with OUD. METHODS: Adults (N=41) in OUD treatment who smoked >5 cigarettes/day (CPD), used EC <3 of prior 30days, and did not want to quit smoking, were randomized to receive an 8 week supply of NIDA's standardized research EC immediately (SREC, n=22) or after an 8-week delay (waitlist control; WLC, n=19). Participants reported past 24-hr CPD and EC use in daily texts for 8 weeks and research assessments and biochemical monitoring (e.g., carbon monoxide [CO]) every 2 weeks for 8 weeks. RESULTS: Participants had a mean age of 50, were 76% male, 88% white. From Baseline (BL) to Week 8, the change in CPD differed significantly between groups (p=0.001) with a larger decrease in CPD in SREC vs. WLC (SREC 15.3 at BL to 7.2 CPD at W8, WLC 14.2 to 12.8). There was a significant reduction in breath CO levels within SREC across the 8-weeks (from 22.9 at BL to 12.5 at W8, p<0.001), that was larger than WLC (23.7 vs. 20.3, p=0.042) (group x time p=0.071). No group differences were observed on nicotine dependence, withdrawal, or OUD stability (p's>0.05). CONCLUSIONS: Provision of ECs to people with OUD who smoke, not planning to quit, resulted in reduced combusted tobacco use, exposure and no worsening withdrawal, dependence, or OUD stability.