Generalized and Domain-Specific Episodic Thinking for Smoking Cessation

Cigarette smoking causes more than a dozen cancers, including cancers of the head and neck, colon, bladder, and lung. Although quitting smoking drastically reduces the risk of cancer mortality, rates of cessation are low, particularly in rural areas and other communities. Current evidence-based treatments for smoking cessation have made progress, but substantial room for innovation remains and novel strategies are needed. Successful smoking cessation may be considered, in part, an intertemporal choice between continuing to smoke and achieving the delayed health benefits associated with quitting (e.g., avoidance of lung cancer). Thus, quitting requires one's behavior to be sufficiently motivated by future outcomes. Unfortunately, robust cross-sectional and longitudinal evidence indicates that people who smoke cigarettes show elevated delay discounting, or a bias for immediate gratification. Prior research shows that delay discounting predicts treatment failure and relapse in smoking cessation. These findings suggest that delay discounting often prevents successful quitting because the health benefits of cessation (e.g., avoiding cancer) are too delayed to motivate sustained behavioral change. Thus, delay discounting is a therapeutic target in smoking cessation, where interventions that increase valuation of future outcomes may facilitate quitting. Episodic future thinking (EFT) is one such scalable intervention that is designed to shift time perspective and reduce bias for immediate gratification by promoting vivid and frequent visualization of a broad range of personally significant future events (e.g., weddings, birthdays, spending time with loved ones). In laboratory studies, research has shown that this form of generalized EFT in cigarette smokers reduces delay discounting and motivation to smoke (i.e., cigarette consumption, craving, and valuation). Moreover, strong preliminary evidence suggests that cancer-related EFT, a novel form of the intervention that involves visualizing the future experience of smoking-related lung cancer, may be more efficacious for reducing urges to smoke than the generalized form. The proposed trial will adapt both forms of EFT (generalized and cancer-related) for clinical use in smoking cessation. Remote intervention delivery and outcomes assessment (breath carbon monoxide and number of cigarettes smoked per day) will be used to minimize clinical burden and increase intervention reach and access, including in rural populations who often lack access to evidence-based treatments for smoking cessation. In an eight-week proof-of-concept trial, participants will be prompted to engage in EFT or control episodic thinking multiple times per day and during acute craving episodes. Specific Aims 1 and 2 will examine the feasibility and efficacy, respectively, of generalized and cancer-related EFT to reduce smoking. An Exploratory Aim will investigate the potential moderating role of income, education, sex, and other characteristics (e.g., baseline delay discounting, cigarettes/day) in the effects of EFT on smoking outcomes.

• Episodic Future Thinking (EFT) (Behavioral): Participants will engage in EFT for 8 weeks, three times a day. Participants will receive three daily text messages. Each prompt will link to a custom web interface that guides participants to read and vividly imagine one of their cues, chosen randomly. Visit times and durations will be recorded.
• Episodic Recent Thinking (ERT) (Behavioral): Participants will engage in ERT for 8 weeks, three times a day. Participants will receive three daily text messages. Each prompt will link to a custom web interface that guides participants to read and vividly imagine one of their cues, chosen randomly. Visit times and durations will be recorded.
• Domain-specific episodic thinking (Behavioral): Content of the episodic thinking intervention will experiencing the symptoms of lung cancer during a broad range of personally meaningful, otherwise positive, events (e.g., social events, celebrations, spending times with friends and family).
• Generalized episodic thinking (Behavioral): Content of the episodic thinking intervention will include a broad range of personally meaningful, positive, events (e.g., social events, celebrations, spending times with friends and family).

Primary outcomes

• Cigarettes smoked per day [From Week 0 to the end of treatment at 8 weeks]: A timeline followback questionnaire will be used to assess the number of cigarettes smoked per day. Lower values reflect better outcomes.

Secondary outcomes

• Other tobacco/nicotine product use per day [From Week 0 to the end of treatment at 8 weeks]: A timeline followback questionnaire will be used to assess the number of times participants use other tobacco/nicotine products per day (excluding cigarettes and nicotine patch). Lower values reflect better outcomes.
• 7-day point prevalence cigarette abstinence [Week 8]: A timeline followback questionnaire will be used to assess cigarette abstinence status (binary) over the final seven days of the intervention.

Other outcomes

• Nicotine patch adherence (feasibility outcome) [From Week 1 to the end of treatment at 8 weeks]: A timeline followback questionnaire will be used to assess frequency of use of the study-provided nicotine patches. Higher values reflect better adherence to nicotine replacement therapy.
• Depressive symptoms (feasibility outcome) [From Week 0 to the end of treatment at 8 weeks]: Depression symptoms over the last 2 weeks will be assessed using the Patient Health Questionnaire-8 (PHQ-8). Total scores on this scale range from 0 (no depressive symptoms) to 24 (severe depressive symptoms).
• Anxiety symptoms (feasibility outcome) [From Week 0 to the end of treatment at 8 weeks]: Anxiety symptoms over the last 2 weeks will be assessed using the Generalized Anxiety Disorder-7 (GAD-7) questionnaire. Total scores on this scale range from 0 (no anxiety symptoms) to 21 (severe anxiety symptoms).
• Episodic thinking adherence (feasibility outcome) [From Week 1 to the end of treatment at 8 weeks]: Adherence to the episodic thinking interventions will be measured as the percentage of daily cue prompts that participants access.
• Perceived convenience (feasibility outcome) [From Week 1 to the end of treatment at 8 weeks]: Participants will evaluate perceived convenience of the intervention, both overall and its individual components, using visual analog scales with ratings ranging from 0 to 100. Higher ratings reflect greater convenience
• Perceived helpfulness (feasibility outcome) [From Week 1 to the end of treatment at 8 weeks]: Participants will evaluate perceived helpfulness of the intervention, both overall and its individual components, using visual analog scales with ratings ranging from 0 to 100. Higher ratings reflect greater helpfulness.

Sex: All, ages: 21 Years to any

Inclusion Criteria:

* smoked cigarettes daily for the last 30 days;
* salivary cotinine > 30 ng/mL, consistent with tobacco use;
* plan to quit smoking in the next 30 days

Exclusion Criteria:

* prior diagnosis with a smoking-related illness (e.g., respiratory disease);
* past 30-day use any smoking cessation treatment;
* anxiety or mood disorders; and
* medical contraindications for use of nicotine replacement therapy (e.g. pregnancy).

• Jeffrey Stein, PhD, Principal investigator, Virginia Polytechnic Institute and State University

NIH grants: R21CA294049