Voucher Based Incentives to Treat Pregnant Smokers

Study Overview
=================
Brief Summary
-----------------
The major goal of this project is to examine the efficacy of a voucher-based incentive program for promoting smoking cessation (Study 1) and preventing relapse (Study 2) during pregnancy and postpartum. Identifying efficacious interventions to increase cessation rates and decrease relapse among those who are able to quit is important to improving U.S. public health.

Detailed Description
-----------------
Maternal cigarette smoking is the leading preventable cause of poor pregnancy outcomes and pediatric morbidity and mortality in the U.S. Efficacious interventions have been developed for smoking cessation during pregnancy, but cessation rates are low, typically under 20%. Efficacious interventions to prevent postpartum relapse remain to be developed. This application seeks support for a Stage II behavioral therapies development project to continue examining interventions to increase smoking cessation above the low levels noted above and to decrease postpartum relapse. With regard to cessation, we conducted studies during the prior funding period showing that voucher-based incentives delivered contingent on biochemically-verified abstinence promote smoking cessation in approximately 40% of women who were still smoking at their 1st prenatal visit compared to only 9% in a control condition. Comparable studies on decreasing postpartum relapse among women who were smokers upon learning of their pregnancy but quit by their 1st prenatal visit (spontaneous quitters) supported the efficacy of abstinence-contingent vouchers for preventing antepartum but not postpartum relapse. We also completed secondary studies on appropriate cutpoints for biochemically verifying smoking status in pregnant women, characterizing the quantitative relationship between smoking exposure and fetal growth, the time-course of depressive symptoms during pregnancy in smokers and abstainers, and the incidence and severity of nicotine withdrawal. While the treatment effect on smoking cessation during pregnancy noted above is at least two-fold greater than usual outcomes, the majority of women, especially heavier smokers (> 10 cigs/day), failed to quit. In Study 1 of this application we propose to experimentally examine whether a revised voucher program designed to increase initial abstinence and encourage additional quit attempts among those who initially fail can promote cessation at the end-of-pregnancy assessment in the majority of women treated (> 60%). Considering that nobody has succeeded in decreasing postpartum relapse among spontaneous quitters, we are not surprised that our first effort was unsuccessful. In Study 2 of this application we propose to experimentally test whether a revised voucher-based incentive program designed to more effectively reinforce sustained abstinence will decrease postpartum relapse. We are also proposing to continue secondary studies on biochemical verification of smoking status, fetal growth, and predictors of postpartum relapse. Overall, the proposed studies have the potential to contribute important new information on effective treatments for one of our nation's most daunting drug abuse problems.

Official Title
-----------------
Phase 2 Study of the Efficacy of Voucher-Based Incentives to Treat Pregnant Smokers

Conditions
-----------------
Efficacy of Financial Incentives

Intervention / Treatment
-----------------
* Behavioral: Voucher-based incentives


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Only women will participate in the proposed study, because the overarching aim is to develop efficacious treatments for smoking cessation and relapse prevention during pregnancy and early postpartum. All participants will be currently pregnant and report being smokers at the time of conception. Those in Study 1 will report continuing to smoke upon entering prenatal care. Those in Study 2 will report having already quit smoking upon entering prenatal care. Women must reside in the county in which the clinic is located, plan to reside in this geographical area through 6 months postpartum, be < 25 weeks gestation, not be living in a group residence, English speaking, and not regularly receiving psychotropics other than antidepressants. - Exclusion Criteria: Women receiving opioid substitution therapy will be excluded. In Vermont, minorities comprise 4% of the general population. There will be no exclusion criteria concerning race or ethnicity. In our studies during the prior funding period, approximately 5% of participants were minorities. We anticipate a similar sample in the proposed studies. We shall do all that we can to assure that minorities are included in the research. -

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Original contingent vouchers schedule<br>Women will receive an abstinence-contingent voucher-based incentives intervention (Contingency Management) for smoking cessation and relapse prevention. | Behavioral: Voucher-based incentives<br> <br> * Other names: Contingency Management;|
| Experimental: Revised contingent vouchers schedule<br>Women receive abstinence-contingent voucher-based incentives (Contingency Management) intervention designed to further increase cessation and relapse prevention rates. | Behavioral: Voucher-based incentives<br> <br> * Other names: Contingency Management;|
| Sham Comparator: Non-contingent vouchers schedule<br>This serves as a control condition wherein women earn incentives independent of smoking status. | Behavioral: Voucher-based incentives<br> <br> * Other names: Contingency Management;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Biochemical verification of smoking status. |  | 15 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| birth outcomes | Assessing the impact of smoking cessation on birth outcomes. | 9 months | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
pregnancy, cigarette smoking, incentives, smoking cessation, birth outcomes