Danielle R. Davis

A review of the literature on contingency management in the treatment of substance use disorders, 2009-2014.

This report describes a systematic literature review of voucher and related monetary-based contingency management (CM) interventions for substance use disorders (SUDs) over 5.2years (November 2009 through December 2014). Reports were identified using the search engine PubMed, expert consultations, and published bibliographies. For inclusion, reports had to (a) involve monetary-based CM; (b) appear in a peer-reviewed journal; (c) include an experimental comparison condition; (d) describe an original study; (e) assess efficacy using inferential statistics; (f) use a research design allowing treatment effects to be attributed to CM. Sixty-nine reports met inclusion criteria and were categorized into 7 research trends: (1) extending CM to special populations, (2) parametric studies, (3) extending CM to community clinics, (4) combining CM with pharmacotherapies, (5) incorporating technology into CM, (6) investigating longer-term outcomes, (7) using CM as a research tool. The vast majority (59/69, 86%) of studies reported significant (p<0.05) during-treatment effects. Twenty-eight (28/59, 47%) of those studies included at least one follow-up visit after CM was discontinued, with eight (8/28, 29%) reporting significant (p<0.05) effects. Average effect size (Cohens d) during treatment was 0.62 (95% CI: 0.54, 0.70) and post-treatment it was 0.26 (95% CI: 0.11, 0.41). Overall, the literature on voucher-based CM over the past 5years documents sustained growth, high treatment efficacy, moderate to large effect sizes during treatment that weaken but remain evident following treatment termination, and breadth across a diverse set of SUDs, populations, and settings consistent with and extending results from prior reviews.

Addiction Potential of Cigarettes With Reduced Nicotine Content in Populations With Psychiatric Disorders and Other Vulnerabilities to Tobacco Addiction.

Importance A national policy is under consideration to reduce the nicotine content of cigarettes to lower nicotine addiction potential in the United States. Objective To examine how smokers with psychiatric disorders and other vulnerabilities to tobacco addiction respond to cigarettes with reduced nicotine content. Design, Setting, and Participants A multisite, double-blind, within-participant assessment of acute response to research cigarettes with nicotine content ranging from levels below a hypothesized addiction threshold to those representative of commercial cigarettes (0.4, 2.3, 5.2, and 15.8 mg/g of tobacco) at 3 academic sites included 169 daily smokers from the following 3 vulnerable populations: individuals with affective disorders (n = 56) or opioid dependence (n = 60) and socioeconomically disadvantaged women (n = 53). Data were collected from March 23, 2015, through April 25, 2016. Interventions After a brief smoking abstinence, participants were exposed to the cigarettes with varying nicotine doses across fourteen 2- to 4-hour outpatient sessions. Main Outcomes and Measures Addiction potential of the cigarettes was assessed using concurrent choice testing, the Cigarette Purchase Task (CPT), and validated measures of subjective effects, such as the Minnesota Nicotine Withdrawal Scale. Results Among the 169 daily smokers included in the analysis (120 women [71.0%] and 49 men [29.0%]; mean [SD] age, 35.6 [11.4] years), reducing the nicotine content of cigarettes decreased the relative reinforcing effects of smoking in all 3 populations. Across populations, the 0.4-mg/g dose was chosen significantly less than the 15.8-mg/g dose in concurrent choice testing (mean [SEM] 30% [0.04%] vs 70% [0.04%]; Cohen d = 0.40; P < .001) and generated lower demand in the CPT (&agr; = .027 [95% CI, 0.023-0.031] vs &agr; = .019 [95% CI, 0.016-0.022]; Cohen d = 1.17; P < .001). Preference for higher over lower nicotine content cigarettes could be reversed by increasing the response cost necessary to obtain the higher dose (mean [SEM], 61% [0.02%] vs 39% [0.02%]; Cohen d = 0.40; P < .001). All doses reduced Minnesota Nicotine Withdrawal Scale total scores (range of mean decreases, 0.10-0.50; Cohen d range, 0.21-1.05; P < .001 for all), although duration of withdrawal symptoms was greater at higher doses (&eegr;2 = 0.008; dose-by-time interaction, P = .002). Conclusions and Relevance Reducing the nicotine content of cigarettes may decrease their addiction potential in populations that are highly vulnerable to tobacco addiction. Smokers with psychiatric conditions and socioeconomic disadvantage are more addicted and less likely to quit and experience greater adverse health impacts. Policies to reduce these disparities are needed; reducing the nicotine content in cigarettes should be a policy focus.

Comparison of nicotine dependence indicators in predicting quitting among pregnant smokers.

Research in the general population of smokers indicates that across various measures of nicotine dependence, time to first cigarette (TTFC) is the strongest single-item predictor of quitting success. Whether those findings generalize to pregnant smokers is unclear. To investigate this matter, we compared TTFC with cigarettes per day (CPD) and the Heaviness of Smoking Index (HSI; Kozlowski, Porter, Orleans, Pope, & Heatherton, 1994) in predicting late-pregnancy abstinence among 289 pregnant women enrolled in 4 smoking-cessation trials assessing the efficacy of financial incentives. Logistic regression was used to compare predictors, with model fit measured using the c statistic (range = 0.5, poor prediction to 1.0, perfect prediction). In simple regressions, model fit was comparable across the 3 measures although strongest for CPD alone (c = 0.70, 0.68, 0.66 for CPD, HSI, and TTFC, respectively). In a stepwise multiple regression, treatment was entered first (c = 0.67), then CPD (c = 0.77), quit attempts prepregnancy (c = .81), TTFC (c = .82), and quit attempts during pregnancy (c = .83). We saw no evidence supporting TTFC as the optimal predictor of quitting among pregnant smokers. Instead, the evidence supported using CPD and TTFC together or CPD alone if using only a single predictor.

Preventing relapse after incentivized choice treatment: A laboratory model☆

Two experiments with rats examined relapse of an operant behavior that occurred after the behavior was suppressed by reinforcing (incentivizing) an alternative behavior. In the first phase, a target response (R1) was reinforced. In a treatment phase, R1 was still reinforced, but a new response (R2) was introduced and associated with a larger reinforcer. As in human contingency management treatments, incentivizing R2 this way was effective at suppressing R1. However, when R2s reinforcement was discontinued, there was a robust and immediate relapse to R1. Experiment 1 found that the strength of R1 during relapse testing was not different from that seen in a no treatment control. Experiment 2 found that relapse could nevertheless be reduced by presenting reinforcers not contingent on responding during the test. Either the reinforcer for R1 or the reinforcer for R2 (which were qualitatively different types of food pellets) were effective. The experiments introduce a laboratory method for studying relapse and how to prevent it after contingency management treatments, and suggest at least one treatment that discourages relapse. The incentivized choice paradigm differs from other models of relapse of operant behavior (e.g., resurgence, renewal, reinstatement) in that it does not focus on the return of behaviors that are inhibited by extinction.

A review of the effects of very low nicotine content cigarettes on behavioral and cognitive performance

The present systematic review examines whether very low nicotine content (VLNC) cigarettes ameliorate withdrawal-induced impairments in behavioral/cognitive performance. PubMed, PsycInfo, and Web of Science were searched for performance effects of VLNC cigarettes. For inclusion, reports had to be in English, published in a peer-reviewed journal through June 2017, examine VLNC cigarettes (<0.2mg nicotine yield), include ≥2hour smoking abstinence or reduced nicotine exposure, and examine performance. 19 of 1243 articles reviewed met inclusion criteria. Poorer performance after smoking VLNC versus normal nicotine content (NNC) cigarettes was observed across 7 of 10 domains, including reaction time (8/11), short-term memory (3/10), sustained attention (4/6), inhibitory control (1/4), long-term memory (3/3 studies), and response variability (2/2). In two studies, combining VLNC smoking with nicotine replacement therapy (NRT) resulted in performance that was comparable to performance after NNC smoking. VLNC versus NNC differences were not discerned in motor control/functioning (0/2), visuospatial processing (0/2), learning (0/1), or verbal fluency (0/1). Eleven of nineteen (58%) studies were rated of Good or Excellent quality. Overall, VLNC cigarettes may not fully ameliorate withdrawal-induced disruptions in performance, although this varies by domain, with the strongest evidence for reaction time. Importantly, combining VLNC cigarettes with NRT appears to ameliorate withdrawal that is not reduced by VLNC cigarettes alone. As only 19 studies were identified, many domains are under-investigated. A more thorough evaluation of the extent to which VLNC cigarettes affect withdrawal-impaired performance may be warranted.

Financial Incentives for Reducing Smoking and Promoting Other Health-Related Behavior Change in Vulnerable Populations:

Substantial reductions in U.S. cigarette smoking and associated chronic diseases over the past 50 years have benefited health. Unfortunately, those reductions have distributed unevenly throughout the population. Smoking remains prevalent and even increasing among certain vulnerable populations: economically disadvantaged groups, those with other substance-use disorders or mental illness, certain ethnic and racial minorities, and gender and sexual minorities. Moreover, other unhealthy behavior patterns (physical inactivity, unhealthy food choices, risky sexual behavior, poor adherence to medical preventive regimens) and associated chronic diseases are also overrepresented in many of these same populations. Disparities in unhealthy behavior patterns contribute to health disparities and escalating health care costs, underscoring the need for more effective behavior-change strategies. This report reviews research on the efficacy of financial incentives for reducing smoking in vulnerable populations, while also touching on applications of that behavior-change strategy for promoting other health-related behavior changes in vulnerable populations.

Response to reduced nicotine content cigarettes among smokers with chronic health conditions

Individuals with chronic health conditions persist in smoking despite the presence of smoking-related illness. The aim of this study was to examine whether chronic health conditions moderate response to reduced nicotine content cigarettes (0.4, 2.4, 5.2, 15.8 mg/g of tobacco). This is a secondary analysis of a controlled clinical laboratory study that examined the acute effects of cigarettes varying in nicotine content among individuals especially vulnerable to smoking and tobacco dependence. Participants in the present study were categorized as having 0, 1–2, or ≥3 smoking-related chronic health conditions (i.e., chronic condition severity, CCS). Repeated-measures analysis of variance was used to examine whether CCS moderated response to cigarettes across measures of addiction potential (i.e., concurrent choice testing between nicotine dose pairs, Cigarette Purchase Task (CPT) performance, positive subjective effects), tobacco withdrawal, cigarette craving, and smoking topography. No main effects of CCS or interactions of CCS and nicotine dose were observed for concurrent choice testing, positive subjective effects, tobacco withdrawal, or smoking topography. Main effects of CCS were noted on the CPT with greater CCS being associated with less persistent demand. There was an interaction of CCS and nicotine dose on Factor 1 of the Questionnaire on Smoking Urges with the effects of dose significant only among those with 1–2 chronic conditions. Overall, we see minimal evidence that chronic condition severity affects response to reduced nicotine content cigarettes. A policy that reduces the nicotine content of cigarettes to minimally addictive levels may benefit smokers already experiencing smoking-related chronic conditions.

Response to reduced nicotine content cigarettes among smokers differing in tobacco dependence severity

This study examines whether tobacco dependence severity moderates the acute effects of reducing nicotine content in cigarettes on the addiction potential of smoking, craving/withdrawal, or smoking topography. Participants (N = 169) were daily smokers with mild, moderate, or high tobacco-dependence severity using the Heaviness of Smoking Index. Following brief abstinence, participants smoked research cigarettes varying in nicotine content (0.4, 2.4, 5.2, 15.8 mg nicotine/g tobacco) in a within-subject design. Results were analyzed using repeated measures analysis of co-variance. No main effects of dependence severity or interactions with nicotine dose were noted in relative reinforcing effects in concurrent choice testing or subjective effects on the modified Cigarette Evaluation Questionnaire. Demand for smoking in the Cigarette Purchase Task was greater among more dependent smokers, but reducing nicotine content decreased demand independent of dependence severity. Dependence severity did not significantly alter response to reduced nicotine content cigarettes on the Minnesota Tobacco Withdrawal Scale nor Questionnaire of Smoking Urges-brief (QSU) Factor-2 scale; dependence severity and dose interacted significantly on the QSU-brief Factor-1 scale, with reductions dependent on dose among highly but not mildly or moderately dependent smokers. Dependence severity and dose interacted significantly on only one of six measures of smoking topography (i.e., maximum flow rate), which increased as dose increased among mildly and moderately but not highly dependent smokers. These results suggest that dependence severity has no moderating influence on the ability of reduced nicotine content cigarettes to lower the addiction potential of smoking, and minimal effects on relief from craving/withdrawal or smoking topography.

Modeling nicotine regulation: A review of studies in smokers with mental health conditions

Smokers with mental health conditions (MHCs) lose approximately 15 years of life relative to non-smokers without MHCs, of which two-thirds are attributable to smoking. The Food and Drug Administration (FDA) recently announced a new regulatory strategy for tobacco that includes a reduction in the nicotine content of cigarettes sold in the US to a minimally-addictive level. This action could improve cessation rates in smokers with MHCs by reducing their dependence on nicotine. However, nicotine reduction also could have unintended negative consequences in smokers with MHCs. Thus, it is important to conduct randomized controlled trials to investigate the potential effects of nicotine reduction in smokers with MHCs. Several studies of the acute or extended effects of nicotine reduction in smokers with emotional disorders or serious mental illness have been recently completed or are underway. Studies to date indicate that when smokers with MHCs are switched, under randomized, double-blind conditions, to cigarettes with very low nicotine content, they reduce their cigarette intake, with minimal or no effects on withdrawal, psychiatric symptoms, or compensatory smoking. However, some deleterious effects of nicotine reduction on cognitive performance measures in smokers with schizophrenia have been observed, which are offset by providing concurrent nicotine replacement. We review these studies and provide suggestions for potentially increasing the effectiveness of a nicotine reduction strategy for reducing smoking in people with MHCs. The research described was conducted in the United States in 2010-2018.

Changing Drug Use and Other Health-Related Behavior in Vulnerable Populations

The USA lags far behind other industrial countries on major markers of population health. When population health experts assess this situation, they identify unhealthy behavior patterns (e.g., cigarette smoking, other substance use disorders, physical inactivity and poor food choices, and nonadherence with the recommended medical regimens) as the largest contributor to the status quo. These behavior patterns increase risk for chronic diseases (e.g., cardiovascular disease, site-specific cancers, and type-2 diabetes) and associated premature death. Hence, identifying strategies to promote and sustain behavior change is critical to resolving this national problem. Because these risk behaviors are overrepresented in socioeconomically disadvantaged and other vulnerable populations, they also drive health disparities. In this report, we review research that focuses on identifying effective behavior-change strategies for reducing drug use and other risk behaviors in vulnerable populations. An extensive body of experimental preclinical and clinical research demonstrates that the reinforcement process plays a fundamental role in the acquisition and maintenance of drug use and other unhealthy behavior patterns. The research discussed here illustrates how that same reinforcement process can be leveraged in the form of incentives and other strategies to promote and sustain behavior change. The overarching focus is on drug use, but we also review research with other types of health problems, illustrating the trans-disease influence of reinforcement and the broad generality of behavior-change strategies that leverage that process.