Timing of smoking cessation treatment integrated into outpatient treatment with medications for opioid use disorder: Feasibility trial

Introduction: Cigarette smoking rates among individuals with opioid use disorder (OUD) are notoriously high and may be improved by considering the timing of treatment integration for these two substances. The current study examined the feasibility of a method for assessing the timing of integrating smoking cessation pharmacotherapy within three different phases of outpatient treatment with medication for OUD (MOUD). Methods: Seventy-four buprenorphine-maintained smokers were enrolled in a quasi-experimental study across three MOUD treatment phases: 0–90 (Phase 1), 91–365 (Phase 2), and > 365 days of MOUD treatment (Phase 3). During a 12-week varenicline-based intervention, the study assessed outcomes daily via text messages (cigarette smoking, varenicline adherence, side effects) or monthly at in-person visits (quit motivation and carbon monoxide levels). Results: Thirty-five participants completed the study, with a lower retention rate in Phase 1 (37.5%) relative to Phases 2 (53.5%) or 3 (57.1%). A trend occurred for Phase 1 participants to report aversive side effects (e.g., abnormal dreams, gastrointestinal distress) on more study days. Among completers, adherence to text messaging and varenicline use was high and independent of MOUD treatment phase. Participants in all phases reported declines in cigarette smoking and increases in quit motivation over time; the study observed biochemically verified tobacco abstinence among only a few participants from Phases 2 or 3. Conclusions: This feasibility study demonstrates a method to evaluate the timing of treatment integration for cigarette smoking and MOUD. Method strengths include a study schedule that coincided with the MOUD clinic schedule and use of text messaging to encourage varenicline adherence and evaluate outcomes regularly.