Tobacco Smoking
Conditions
Keywords
Smoking Cessation, Homelessness, Financial Incentives
Brief summary
This community-based randomized controlled trial will test the effect of contingent financial rewards on smoking abstinence among homeless-experienced adult cigarette smokers. Participants will be recruited from 3 Boston Health Care for the Homeless Program locations: a shelter clinic, a day center clinic, and a medical center clinic. All participants will be offered a varenicline prescription and tobacco coaching. Incentive arm participants will receive escalating financial rewards for saliva cotinine levels \<30 ng/ml, assessed 10 times over 12 weeks. Embedded qualitative interviews will explore the mechanisms of on-treatment and post-treatment effects of financial incentives on smoking abstinence in the context of homelessness.
Detailed description
People experiencing homelessness have a 3.5-fold higher prevalence of cigarette smoking in comparison to non-homeless people, contributing to 2-fold higher rates of lung cancer and 3- to 5-fold higher rates of tobacco-attributable death. Homeless smokers want to quit, but studies have not yet uncovered the optimal approach to help them do so. In an 8-week pilot randomized controlled trial (RCT) at Boston Health Care for the Homeless Program (BHCHP), we found that financial incentives for smoking abstinence were associated with 7-fold higher odds of brief smoking abstinence in comparison to a non-incentivized control condition. These results suggest that financial incentives are a promising approach for reducing smoking in this vulnerable population, but further investigation in a larger sample is needed to improve the duration of on-treatment abstinence, assess post-treatment effects, and better understand mechanisms of action and contextual factors that may influence treatment response. To address the above gaps in evidence, we will conduct a community-based RCT of financial incentives for smoking abstinence among adult smokers at BHCHP. Recognized as a leader in homeless health care, BHCHP serves 12,000 currently and formerly homeless patients annually throughout greater Boston. We will randomize 180 participants recruited from 3 BHCHP sites: a shelter clinic, a day center clinic, and a medical center clinic. All participants will be offered 12 weeks of varenicline, 5 sessions of tobacco coaching, and 10 cotinine monitoring visits over a 12-week period. Participants randomized to the financial incentives arm (n=90) will receive escalating debit card payments (range $25-$70) at each monitoring visit for saliva cotinine levels \<30 ng/ml. Control arm participants (n=90) will receive a fixed payment ($10) at each monitoring visit regardless of their saliva cotinine level. We will use an embedded-experiment mixed methods design, where qualitative ('qual') data collection is embedded within a larger quantitative ('QUAN') RCT with the following specific aims: Aim 1. (QUAN) To determine the effect of the financial incentives intervention on cotinine-verified 7-day smoking abstinence at A) the end of treatment (12 weeks) and B) 12 weeks after treatment (24 weeks). Hypotheses: Incentive arm participants will have significantly greater cotinine-verified 7-day smoking abstinence than control arm participants at A) 12 weeks and B) 24 weeks. Aim 2. (qual) To assess why, how, and under what circumstances homeless smokers A) achieve abstinence in response to financial incentives and B) maintain abstinence after incentives are stopped. Interviews with participants at A) 12 weeks (N=30) and B) 24 weeks (N=20) will examine cognitive ('why?'), procedural ('how?'), and contextual ('under what circumstances?') dimensions of their response to financial incentives to generate hypotheses about potential mechanisms for on-treatment and post-treatment effects and to inform modifications of the intervention for future use.
Interventions
Escalating financial rewards for saliva cotinine levels \<30 ng/mL, assessed 10 times over 12 weeks
* Day 1 - 3: 0.5 mg daily * Day 4 - 7: 0.5 mg twice daily * Day 8 - Week 12: 1 mg twice daily * Dose/schedule may be adjusted based on medical history and clinician judgement
5 one-on-one tobacco cessation coaching sessions over 12 weeks
Sponsors
Study design
Eligibility
Inclusion criteria
* Age ≥18 years old * Lifetime smoker of ≥100 cigarettes with current daily smoking of ≥5 cigarettes per day, verified by a saliva cotinine level of ≥30 ng/mL * Ready to try quitting smoking within the next 3 months * Proficient in English * Currently or formerly homeless * Have a primary care provider within BHCHP system
Exclusion criteria
* Unable to provide informed consent * History of allergic reaction to varenicline * Currently pregnant, planning to become pregnant, or breastfeeding * Past-month suicidal ideation with plan or intent, or past 12-month history of suicidal behaviors or attempts * Psychiatric hospitalization in the past 3 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cotinine-verified 7-day Smoking Abstinence at 12 Weeks | 12 weeks | Point-prevalent smoking abstinence, defined as self-report of not smoking in the past 7 days and verified by a salivary cotinine level \<10 ng/ml. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Cotinine-verified 7-day Smoking Abstinence at 24 Weeks | 24 weeks | Point-prevalent smoking abstinence, defined as self-report of not smoking in the past 7 days and verified by a salivary cotinine level \<10 ng/ml. |
Countries
United States
Participant flow
Recruitment details
Recruitment took place between 2021-2024 at Boston Health Care for the Homeless Program (BHCHP), a federally funded Health Care for the Homeless (HCH) organization. Participants were recruited via in-person outreach at BHCHP clinic sites, telephone outreach to BHCHP patients with a past-year clinical encounter and electronic health record (EHR) documentation of current smoking, self-referrals in response to flyers or word of mouth, and referrals from BHCHP clinicians.
Pre-assignment details
Enrolled participants provided written informed consent and completed a staff-administered baseline survey. To be assigned a study arm, enrolled participants were asked to attend a randomization appointment within 4 weeks of enrollment.
Participants by arm
| Arm | Count |
|---|---|
| Control (n=68) * Varenicline
* Tobacco coaching
* Saliva cotinine monitoring with fixed payments ($10) regardless of results
Varenicline: - Day 1 - 3: 0.5 mg daily
* Day 4 - 7: 0.5 mg twice daily
* Day 8 - Week 12: 1 mg twice daily
* Dose/schedule may be adjusted based on medical history and clinician judgement
Tobacco coaching: 5 one-on-one tobacco cessation coaching sessions over 12 weeks | 68 |
| Financial incentives (n=69) * Varenicline
* Tobacco coaching
* Saliva cotinine monitoring with escalating payments ($25-70) for levels \<30 ng/ml
Financial incentives: Escalating financial rewards for saliva cotinine levels \<30 ng/mL, assessed 10 times over 12 weeks
Varenicline: - Day 1 - 3: 0.5 mg daily
* Day 4 - 7: 0.5 mg twice daily
* Day 8 - Week 12: 1 mg twice daily
* Dose/schedule may be adjusted based on medical history and clinician judgement
Tobacco coaching: 5 one-on-one tobacco cessation coaching sessions over 12 weeks | 69 |
| Total | 137 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| On treatment (0-12 weeks) | Deemed ineligible after randomization due to non-smoking status | 1 | 0 |
| On treatment (0-12 weeks) | Withdrawal by Subject | 2 | 5 |
| On treatment (0-12 weeks) | Withdrawn by PI due to behavioral concerns | 1 | 0 |
| Post-treatment (12-24 weeks) | Death | 1 | 0 |
Baseline characteristics
| Characteristic | Control (n=68) | Total | Financial incentives (n=69) |
|---|---|---|---|
| Age, Continuous | 51.2 years STANDARD_DEVIATION 10.3 | 50.1 years STANDARD_DEVIATION 10.2 | 49.0 years STANDARD_DEVIATION 10.1 |
| Alcohol use disorder | 18 Participants | 27 Participants | 9 Participants |
| Cigarettes per day | 14.3 cigarettes STANDARD_DEVIATION 6.8 | 14.2 cigarettes STANDARD_DEVIATION 7 | 14.1 cigarettes STANDARD_DEVIATION 7.3 |
| Drug use disorder | 40 Participants | 79 Participants | 39 Participants |
| Homelessness status Currently homeless | 36 Participants | 71 Participants | 35 Participants |
| Homelessness status Formerly homeless | 32 Participants | 66 Participants | 34 Participants |
| Moderate/severe anxiety | 28 Participants | 52 Participants | 24 Participants |
| Moderate/severe depression | 25 Participants | 52 Participants | 27 Participants |
| Race/Ethnicity, Customized Race/Ethnicity Hispanic/Latine | 6 Participants | 23 Participants | 17 Participants |
| Race/Ethnicity, Customized Race/Ethnicity Non-Hispanic Black | 17 Participants | 31 Participants | 14 Participants |
| Race/Ethnicity, Customized Race/Ethnicity Non-Hispanic Other | 11 Participants | 21 Participants | 10 Participants |
| Race/Ethnicity, Customized Race/Ethnicity Non-Hispanic White | 34 Participants | 60 Participants | 26 Participants |
| Race/Ethnicity, Customized Race/Ethnicity Unknown | 0 Participants | 2 Participants | 2 Participants |
| Sex/Gender, Customized Gender Female | 24 Participants | 35 Participants | 11 Participants |
| Sex/Gender, Customized Gender Male | 44 Participants | 100 Participants | 56 Participants |
| Sex/Gender, Customized Gender Other | 0 Participants | 2 Participants | 2 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 1 / 69 | 0 / 69 |
| other Total, other adverse events | 43 / 69 | 37 / 69 |
| serious Total, serious adverse events | 3 / 69 | 2 / 69 |
Outcome results
Cotinine-verified 7-day Smoking Abstinence at 12 Weeks
Point-prevalent smoking abstinence, defined as self-report of not smoking in the past 7 days and verified by a salivary cotinine level \<10 ng/ml.
Time frame: 12 weeks
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Control (n=68) | Cotinine-verified 7-day Smoking Abstinence at 12 Weeks | 3 Participants |
| Financial incentives (n=69) | Cotinine-verified 7-day Smoking Abstinence at 12 Weeks | 4 Participants |
Cotinine-verified 7-day Smoking Abstinence at 24 Weeks
Point-prevalent smoking abstinence, defined as self-report of not smoking in the past 7 days and verified by a salivary cotinine level \<10 ng/ml.
Time frame: 24 weeks
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Control (n=68) | Cotinine-verified 7-day Smoking Abstinence at 24 Weeks | 3 Participants |
| Financial incentives (n=69) | Cotinine-verified 7-day Smoking Abstinence at 24 Weeks | 5 Participants |