Financial Incentives for Smoking Cessation Among Disadvantaged Pregnant Women

Study Overview
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Brief Summary
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Investigators will examine whether adding financial incentives to current best practices for smoking cessation during pregnancy (i.e., referral to pregnancy-specific counseling using a telephone quit line) increases cessation rates and improves infant health. While more expensive upfront compared to best practices alone, the investigators hypothesize that this treatment approach will be economically justified by the later cost savings associated with more women quitting, having healthier babies, and needing less healthcare. It should also help to reduce the greater risk for health problems often seen among those who less well off economically.

Detailed Description
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Smoking during pregnancy is the leading preventable cause of poor pregnancy outcomes in the U.S. Most pregnant smokers continue smoking through pregnancy producing serious immediate and longer-term adverse health consequences for the infant. Smoking during pregnancy is highly associated with economic disadvantage and a substantive contributor to health disparities. Efficacious interventions are available, but cessation rates are low (<20%) and improvements in birth outcomes often modest or absent. Current treatments usually entail relatively brief, lower-cost interventions (e.g., pregnancy specific quit lines). There is broad consensus that more effective interventions are sorely needed. This team of investigators has developed a novel behavioral economic intervention in which women earn financial incentives contingent on smoking abstinence. In a metaanalysis of treatments for smoking during pregnancy, effect sizes achieved with financial incentives were several fold larger than those achieved with lower intensity approaches or medications. The intervention also appears to improve birth outcomes and increase breastfeeding duration. While highly promising, further research is needed in at least three areas. (1) The evidence on birth outcomes and breastfeeding is from studies that combined data across trials rather than a single prospective trial, (2) whether the intervention produces other postpartum improvements in health has not been investigated, and (3) the overall cost-effectiveness of this approach has not been examined. To examine these unanswered questions, the investigators are proposing a randomized, controlled clinical trial comparing the efficacy and cost effectiveness through one year postpartum of current best practices for smoking cessation during pregnancy vs. best practices plus financial incentives among 230 pregnant, Medicaid recipients. A third condition of 115 pregnant nonsmokers matched to the smokers on sociodemographic and health conditions will be included as well to compare the extent to which the treatments reduce the burden of smoking and to estimate how much more might be accomplished by further improvements in this incentives intervention without exceeding cost-effectiveness. The investigators hypothesize that best practices plus financial incentives will be more effective than usual care practices alone, that the incentives intervention will be cost effective, and that while adding the incentives reduces a greater proportion of the health and economic burden of smoking than best practices alone, more can be done while remaining cost effective. Overall, the proposed study has the potential to substantially advance knowledge on cost-effective smoking cessation for pregnant women. Importantly, because of the strong association between smoking during pregnancy and economic disadvantage, the proposed study also has the potential to contribute new knowledge relevant to reducing the serious challenges of health disparities.

Official Title
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Financial Incentives for Smoking Cessation Among Disadvantaged Pregnant

Conditions
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Cigarette Smoking

Intervention / Treatment
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* Behavioral: Best practices
* Behavioral: financial incentives


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria for two intervention arms: report being smokers at the time that they learned of the current pregnancy; report smoking in the 7 days prior to the first prenatal care visit with biochemical verification; < 25 weeks gestation; English speaking; plan on remaining in the geographical area through 12months postpartum. Inclusion Criteria for never-smoker comparison condition: report being nonsmokers at the time they learned of the current pregnancy; report no smoking in the past 6 month; Biochemical verification of non-smoker status; report smoking < 100 cigarettes in their lifetime; Exclusion criteria: > 25 weeks gestation; unavailable for routine assessments through 1 year postpartum; opioid substitution therapy; untreated/unstable serious mental illness

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Best practices for pregnant smokers<br>Five As plus referral to pregnancy-specific tobacco quit line | Behavioral: Best practices<br> <br> * Other names: Five As plus referral to pregnancy-specific quit line;|
| Experimental: Best practices plus financial incentives<br>Best practices plus providing financial incentives contingent on biochemically verified abstinence. Incentives are in the form of vouchers exchangeable for retail items and available through 12-weeks postpartum. | Behavioral: Best practices<br> <br> * Other names: Five As plus referral to pregnancy-specific quit line;Behavioral: financial incentives<br>* financial incentives provided contingent on biochemically confirmed smoking abstinence<br>* Other names: contingency management;|
| No Intervention: Never-smoker comparison condition<br>We will follow a group of never-smoker pregnant women matched to smokers on key sociodemographic and obstetrical characteristics for purposes of comparisons in birth/health outcomes at delivery and through 1 year postpartum | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 7-day Point Prevalence Abstinence Levels at Final Antepartum Assessment | Abstinence was defined as woman reports that she has not smoked, not even a puff, in the past 7 days and self-report is biochemically verified via urine cotinine testing | collected once per women at approximately 28-weeks gestation in each of the two smoking arms | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 7-day Point Prevalence Abstinence Postpartum | Compare two treatment arms on 7-day point-prevalence abstinence assessed at 2-, 4-, 8-, 12-, 24- and 48-weeks postpartum. Abstinence was defined as self-report of no smoking in past 7 days, not even a puff, with biochemical verification of self-report using urine cotinine testing | Repeated assessments completed at 2-, 4-, 8-, 12-, 24-, and 48-weeks postpartum | 
| Breastfeeding in the Three Trial Arms | Compare the three trial arms on overall percentage of women continuing to breastfeed at repeated postpartum assessments | Repeated assessments completed at 2-, 4-, 8-, 12-, 24-, and 48-weeks postpartum | 
| Breastfeeding While Abstinent From Smoking | We compared the three trial arms on the percent of women who reported breastfeeding and were biochemically confirmed to be abstinent from smoking at each postpartum assessment. | Repeated assessments completed at 2-, 4-, 8-, 12-, 24-, and 48-weeks postpartum | 
| Craving Item From the Minnesota Nicotine Withdrawal Scale (MNWS). | The craving item is on a 0 (none) to 4 (severe) scale. We report mean (SEM) scores. | Outcomes reported for 8 assessments (early pregnancy, late pregnancy, 2, 4, 8, 12, 24, 28 weeks postpartum. | 
| Nicotine Withdrawal Total Scores for the Two Smoking-cessation Trial Conditions. | Reporting mean total scores and SEM from the Minnesota Nicotine Withdrawal Scale (MNWS). Total score is an average of 7 items, with each item on a 0 (none) to 4 (severe) scale. | Outcomes reported for 8 assessments (early pregnancy, late pregnancy, 2, 4, 8, 12, 24, 28 weeks postpartum. | 
| Infant Growth in First Year of Life | Infant growth (length & weight) expressed a Body Mass Index (BMI) percentile score was assessed at delivery, 24- and 48-week postpartum assessments. | delivery, 24-week, and 50-week postpartum assessments | 
| Birth Outcomes (% Small for Gestational Age Deliveries) | Birth outcomes were compared between the three study arms. Small for gestational age was defined as <10th percentile using INTERGROWTH-21st [2021] https://intergrowth21.tghn.org/about/about-us/. | delivery | 
| Birth Outcomes (Percent Preterm [<37 Weeks] Deliveries) | Compared the three trials conditions on preterm deliveries. | at delivery | 
| Birth Outcomes (NICU Admissions) | Compared three trial conditions on percent of NICU admissions | at delivery | 
| Ages & Stages Questionnaire (ASQ) | The ASQ assesses infant development in five areas (communication [Comm], gross motor [GM], fine motor [FM], problem solving [PrbSlv], personal-social [PerSoc]); Each area includes six items, each with a possible value of 0, 5, 10, along with a cutoff to dichotomize infants into typical/normal vs. monitor/potential delay categories for an area. Scores in each area are compared to norms; scores with 1 standard deviation of the norm mean are categorized as typical/normal and those greater than one standard deviation below the norm mean are categorized as monitor/potential delay. We report the dichotomized outcomes for each of the six areas at the 24-week and 48-week assessments noting the number of infants in each treatment condition in the monitor/potential delay category. | 24- and 48-weeks postpartum | 
| Birth Outcome: Gestational Age at Delivery | Birth outcomes were obtained from the birth record. Gestational age was expressed in weeks. | at delivery | 
| Cost Per Participant | Cost per participant for BP+FI and BP interventions. These costs per participant are used in calculation of the Incremental Cost Effectiveness Ratio (ICER). This ICER measure is the added healthcare sector cost per participant for BP+FI compared to BP relative to estimated net health gain per participant (QALY). Maternal net health gains in QALYs from cessation difference between treatment conditions at 24 weeks postpartum were based on Stapleton & West, 2012, Nicotine Tob Res; 14: 463-71. | Trial entry through 24-weeks postpartum (approximately one year following smoking-cessation quit date). | 
| Quality of Life Years Gained (QALYs) | Smoking abstinence at the 24-week assessment was converted into quality of life years gained using standardized tables reported in Stapleton & West, 2012, Nicotine Tob Res; 14: 463-71. | 24 weeks postpartum | 
| Incremental Cost Effectiveness Ratio (ICER) | A summary measure representing the economic value of an intervention (BP+FI) compared with an alternative (BP). The measure type used below is 'number' due to the fact that this measure is simply a ratio of mean dollars divided by mean years gained between the treatment conditions. Thus there was no alternative measure type that could be used or measure of dispersion available. | 24 weeks postpartum | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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smoking, pregnancy, cessation, incentives