Contingency Management for Smoking Cessation

Randomized Trial of a Contingency Management Smoking Cessation Intervention for Homeless Adults

The prevalence of smoking in the homeless population (70%) is over 4 times that of the general population (15%). Homeless adults have not experienced similar declines in tobacco use as the general population has over the past three decades. Homeless adults are interested in smoking cessation and make quit attempts, but are less successful in quitting smoking than the general population. Trials of group behavioral counseling and pharmacotherapy for smoking cessation have not led to substantial long-term abstinence (i.e., abstinence for 6 months or more), suggesting that these interventions alone are insufficient to improve quit rates among homeless adults. Many homeless adults seek health care in safety net clinics; these clinics could bring cessation interventions to scale. Contingency management is a powerful behavior change intervention that reinforces positive health behaviors through the provision of modest incentives (e.g., cash). In this pilot randomized controlled trial, the investigator will test the feasibility and acceptability of a contingency management intervention that provides incentives for smoking cessation for people experiencing homelessness.

Study Overview

• Status: Completed
• Conditions: Smoking Cessation; Smoking Reduction; Smoking, Tobacco
• Intervention / Treatment: Behavioral: Contingency Management - Increasing; Behavioral: Fixed payments

Detailed Description

In this pilot randomized controlled trial (RCT), the investigator will (1) adapt a known-efficacious extended CM cessation intervention to a novel population and setting, with the ultimate goal of increasing long-term abstinence among homeless adults seeking care in safety net health clinics, (2) develop a corresponding RCT protocol, and (3) conduct a pilot RCT to assess the feasibility and acceptability of the RCT. If the pilot RCT is feasible and acceptable, the investigator will test the adapted intervention in a subsequently-funded, full-scale RCT.

Primary Objectives:

Assess feasibility and acceptability of a CM intervention through:

1. Measuring biochemically-verified point prevalence abstinence at 6 months follow-up.
2. Measuring participant adherence to the protocol.
3. Gathering information on the number of visits attended.
4. Assessing the retention protocol.

Secondary Objectives

Assess feasibility and acceptability of a CM intervention through:

1. Biochemically-verified 7-day point months follow-up at 3 months.
2. Prolonged abstinence at 3 months and 6 months follow-up.
3. Point-prevalent abstinence at 12 months

• Study Type: Interventional
• Enrollment (Actual): 83
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94143
      • University of California, San Francisco
    • San Francisco, California, United States, 94110
      • The Richard H. Fine's People's Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Are 18 years or older
2. Engaged in care at the Tom Waddell Urban Health Center (TWUHC)
3. Meet criteria for homelessness as defined by the Homeless Emergency Assistance and Rapid Transition to Housing Act
4. Are current smokers (smoked at least 100 cigarettes in lifetime, smoked daily in the past 7 days and at least 5 cigarettes per day, verified by expired Carbon Monoxide (CO) >= 8 parts per million (ppm))
5. Have an intention to quit smoking within the next six months
6. Are attending on-site smoking cessation counseling provided by the behavioral counselors
7. Are English proficient
8. Are able to provide informed consent. Patients who are interested in participating but not enrolled in counseling services will be encouraged to engage in counseling sessions at the time of enrollment.

Exclusion Criteria:

1. Are unable to take nicotine replacement therapy (e.g., pregnancy or myocardial infarction (MI) within the past 2 weeks)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Contingency Management (CM); In addition to receiving usual cessation care at the Tom Waddell Urban Health Center (TWUHC), CM intervention participants with CO-verified abstinence will obtain a CM incentive payment, via gift cards and/or cash redeemable in national retail chains.	Behavioral: Contingency Management - Increasing; Increasing incentive payment for abstinent participant
Other: Control Group; Participants who choose to attend smoking cessation in the usual care setting at TWUHC will receive a basic $5 payment for attending each study visit.	Behavioral: Fixed payments; Fixed payments for attending study visits

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants who achieve point prevalence abstinence	The proportion of participants who achieve biochemically-verified 7-day point prevalence abstinence defined as participants (1) reporting not smoking a single cigarette in the past seven days, not even a puff; (2) having carbon monoxide (CO) levels <=5 parts per million (ppm), and (3) urinary anatabine/anabasine assay levels < 2 nanograms per milliliter (ng/ml).	6 months
Median number of carbon monoxide (CO) negative samples	The total number of negative CO specimen samples collected throughout the first 6 months of the program will be reported with 24 maximum possible number of samples per person.	6 months
Median total number of counseling sessions attended	The number of counseling sessions attended per person will will recorded with a maximum of 5 sessions total.	6 months
Proportion of the sample retained as a result of retention procedures over time	The proportion of participants who choose to attend cessation sessions visits at 2 weeks, 1 month, 3 months, 6 months, and 12 months. A participant will be considered lost to follow-up and censored on their last visits if the participants have failed to return for a scheduled visit and the study staff are unable to contact the participant after at least 3 attempts.	Up to 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants who achieve point prevalence abstinence	The proportion of participants who achieve biochemically-verified 7-day point prevalence abstinence defined as participants (1) reporting not smoking a single cigarette in the past seven days, not even a puff; (2) having carbon monoxide (CO) levels <=5 parts per million (ppm)	3 months
Proportion of participants who achieve point prevalence abstinence	The proportion of participants who achieve biochemically-verified 7-day point prevalence abstinence defined as participants (1) reporting not smoking a single cigarette in the past seven days, not even a puff; (2) having carbon monoxide (CO) levels <=5 parts per million (ppm)	12 months
Proportion of participants who achieve prolonged abstinence over time	Prolonged abstinence is defined as participants (1) not smoking a single cigarette since the last visit; (2) having CO levels <=5 ppm	Up to 6 months

Collaborators and Investigators

• Sponsor: University of California, San Francisco
• Collaborators: Tobacco Related Disease Research Program
• Investigators: Principal Investigator: Maya Vijayaraghavan, MD, MAS, University of California, San Francisco

Study record dates

Study Major Dates

• Study Start (Actual): November 9, 2021
• Primary Completion (Actual): June 30, 2024
• Study Completion (Actual): June 30, 2024

Study Registration Dates

• First Submitted: July 23, 2021
• First Submitted That Met QC Criteria: July 23, 2021
• First Posted (Actual): July 29, 2021

Study Record Updates

• Last Update Posted (Estimated): December 5, 2024
• Last Update Submitted That Met QC Criteria: December 3, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: Contingency Management
• Other Study ID Numbers: 21632; NCI-2021-08359 (Registry Identifier: NCI Clinical Trials Reporting Program (CTRP))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No