Prenatal tobacco and tobacco-cannabis co-exposure: Relationship with attention and memory in middle childhood.

We examined associations between prenatal tobacco exposure (with and without cannabis exposure) and children's performance on laboratory measures of sustained attention, attentional set shifting, and working memory in middle childhood (9-12 years of child age). Participants were recruited in the first trimester of pregnancy and oversampled for prenatal tobacco exposure; with a smaller sample (n = 133; n = 34 non-substance exposed, n = 37 exposed to tobacco only, n = 62 co-exposed) invited (oversampled for co-exposure) to participate in the middle-childhood assessment (M age = 10.6, SD = 0.77; 68% Black, 20% Hispanic). Results for sustained attention indicated lower attention (percent hits) at the first epoch for tobacco only exposed compared to non-exposed and co-exposed; a trend (p = .07) towards increases in impulsive responding across time (a total of 8 epochs) for tobacco exposed (with and without cannabis) compared to non-exposed children; and a significant association between higher number of cigarettes in the first trimester and greater increases in impulsive responding across epochs. However, children prenatally exposed to tobacco (with and without cannabis) demonstrated greater short-term memory compared to children not prenatally exposed, and this difference was driven by higher scores for children prenatally co-exposed to tobacco and cannabis compared to those who were non-exposed. Overall, results suggest that prenatal tobacco exposure, especially in the first trimester, may increase risk for impulsive responding on tasks requiring sustained attention, and that co-use of cannabis did not exacerbate these associations. The higher short-term memory scores among children who were co-exposed compared to non-exposed are perplexing and need replication, particularly in studies with larger sample sizes and samples exposed only to cannabis to examine this more closely.

Genetic Prediction of Smoking Cessation Medication Side Effects: A Genome-Wide Investigation of Abnormal Dreams on Varenicline.

Varenicline, the most efficacious smoking cessation monotherapy, produces abnormal dreams. Although genetic contributions to varenicline-associated nausea and cessation have been identified, the role of genetics in abnormal dreams is unknown. We conducted a genomewide association study (GWAS) of abnormal dreams in 188 European ancestry smokers treated with varenicline (NCT01314001). Additive genetic models examined the likelihood of experiencing abnormal dreams 2 weeks following varenicline initiation. For the top locus, we tested for selectivity to varenicline, effects on cessation, replication, and generalizability to African ancestry (AA) individuals. The top GWAS variant associated with abnormal dreams was rs901886, mapping to intron 2 of ICAM5 on chromosome 19. The prevalence of abnormal dreams in those with rs901886 CC, CT, and TT genotypes was 15%, 36%, and 62%, respectively (odds ratio = 2.94 for T vs. C, 95% confidence interval = 1.92-4.55, P = 2.03e-7; T allele frequency = 52%). This rs901886 association was selective to varenicline (P values > 0.05 on nicotine patch and placebo). There were also positive associations for rs901886 T (vs. C allele, P = 0.03) and for abnormal dreams (P = 0.06) with varenicline-aided cessation. Neither rs901886 (P = 0.40) nor abnormal dreams (P = 0.24) were associated with adherence. A similar direction of effect of rs901886 on abnormal dreams was observed in a second varenicline trial (NCT01836276). In AA individuals (n = 137), rs901886 was not associated with abnormal dreams (P = 0.41), but there was an association for a variant located ~ 74.4 kb 5' of ICAM5 (P = 2.56e-3). Variation in ICAM5 may influence abnormal dreams and cessation on varenicline. These findings provide additional support for genetically optimized smoking cessation approaches.

A preliminary randomized trial of reinforcement contingencies to improve compliance with ecological momentary assessment.

Ecological Momentary Assessment (EMA) methods are increasingly used by translational scientists to study real-world behavior and experience. The ability to draw meaningful conclusions from EMA research depends upon participant compliance with assessment completion. Most EMA studies provide financial compensation for compliance, but little empirical evidence addresses the impact of reinforcement parameters on the level of compliance. The purpose of this study-within-a-trial was to determine the effects of varying the amount and frequency of reinforcement on EMA compliance in a clinical sample of individuals seeking treatment for cigarette smoking. In the parent clinical trial, participants were asked to complete 9 weeks of EMA (1 daily Morning Assessment and 4 daily Random Assessments). Following a 5-week Standard Payment phase for EMA compliance, 61 individuals seeking treatment for cigarette smoking enrolled in the larger clinical trial were randomized to receive Standard ($1 per assessment, paid biweekly), Frequent ($1 per assessment, paid 3 times per week), or Large ($2 per assessment, paid biweekly) payments for EMA compliance during a 4-week Payment Manipulation Phase. Overall, receiving Frequent or Large payments did not improve EMA compliance compared to Standard payments, Ps > .30. Varying frequency and amount of remuneration for EMA compliance did not generally improve compliance in an ongoing clinical trial, raising further questions about the importance of reinforcement parameters in promoting EMA compliance.

Previous studies have addressed the idea that monetary compensation for participation in research is an effective way to encourage individuals to complete the studies. However, there has been limited exploration as whether the amount and frequency of compensation has an influence on participant adherence. We recruited adults who were seeking cigarette smoking treatment and asked them to complete multiple assessments each day on a smartphone app for 9 weeks. Following completion of the assessments, participants were given monetary compensation. A change after 5 weeks led to some persons receiving $1 per assessment paid three times a week (Frequent Payment Group), while others received $2 per assessment paid biweekly (Large Payment Group), and some continued to receive $1 per assessment paid biweekly (Standard Payment Group) for the next 4 weeks. We found that the experimental payment variations did not significantly change compliance with the assessments. These preliminary findings serve as a benchmark for further research.

Relationships Between the Nicotine Metabolite Ratio (NMR) and Laboratory Assessments of Smoking Reinforcement and Craving Among Adults in a Smoking Cessation Trial.

INTRODUCTION: People who metabolize nicotine more quickly are generally less successful at quitting smoking. However, the mechanisms that link individual differences in the nicotine metabolite ratio (NMR), a phenotypic biomarker of the rate of nicotine clearance, to smoking outcomes are unclear. We tested the hypotheses that higher NMR is associated with greater smoking reinforcement, general craving, and cue-induced cigarette craving in a treatment-seeking sample. METHODS: Participants were 252 adults who smoke cigarettes enrolled in a randomized controlled smoking cessation trial (NCT03262662) conducted in Buffalo, New York, USA. Participants completed the Choice Behavior Under Cued Conditions (CBUCC) paradigm, a laboratory choice procedure, ~1 week before the first cessation treatment visit, at which time a saliva sample was collected for NMR assessment. On each CBUCC trial, participants reported cigarette craving during cue presentation (cigarette, water) and spent $0.01-0.25 for a chance (5%-95%) to sample the cue (1 puff, sip), providing measures of smoking reinforcement (spending for cigarettes vs. water), general cigarette craving (averaged across cigarette and water cues), and cue-specific craving (cigarette craving during cigarette vs. water cues). RESULTS: As observed in prior work, the NMR was significantly higher among white and female participants. As expected, both spending and cigarette craving were significantly greater on cigarette compared to water trials. However, contrary to our hypotheses, higher NMR was not associated with greater smoking reinforcement, general craving, or cue-specific craving. CONCLUSIONS: The present data do not support that smoking reinforcement or craving are related to nicotine metabolism among individuals seeking to quit smoking. IMPLICATIONS: Though greater smoking reinforcement, general craving, and cue-specific craving are hypothesized to be linked to faster nicotine metabolism, there was no evidence of such relationships in the present sample of adults seeking to quit smoking. Further research, including replication and consideration of alternate hypotheses, is warranted to elucidate the mechanisms by which the NMR is related to smoking cessation.

Evaluating Declines in Compliance With Ecological Momentary Assessment in Longitudinal Health Behavior Research: Analyses From a Clinical Trial.

BACKGROUND: Ecological momentary assessment (EMA) is increasingly used to evaluate behavioral health processes over extended time periods. The validity of EMA for providing representative, real-world data with high temporal precision is threatened to the extent that EMA compliance drops over time. OBJECTIVE: This research builds on prior short-term studies by evaluating the time course of EMA compliance over 9 weeks and examines predictors of weekly compliance rates among cigarette-using adults. METHODS: A total of 257 daily cigarette-using adults participating in a randomized controlled trial for smoking cessation completed daily smartphone EMA assessments, including 1 scheduled morning assessment and 4 random assessments per day. Weekly EMA compliance was calculated and multilevel modeling assessed the rate of change in compliance over the 9-week assessment period. Participant and study characteristics were examined as predictors of overall compliance and changes in compliance rates over time. RESULTS: Compliance was higher for scheduled morning assessments (86%) than for random assessments (58%) at the beginning of the EMA period (P<.001). EMA compliance declined linearly across weeks, and the rate of decline was greater for morning assessments (2% per week) than for random assessments (1% per week; P<.001). Declines in compliance were stronger for younger participants (P<.001), participants who were employed full-time (P=.03), and participants who subsequently dropped out of the study (P<.001). Overall compliance was higher among White participants compared to Black or African American participants (P=.001). CONCLUSIONS: This study suggests that EMA compliance declines linearly but modestly across lengthy EMA protocols. In general, these data support the validity of EMA for tracking health behavior and hypothesized treatment mechanisms over the course of several months. Future work should target improving compliance among subgroups of participants and investigate the extent to which rapid declines in EMA compliance might prove useful for triggering interventions to prevent study dropout. TRIAL REGISTRATION: ClinicalTrials.gov NCT03262662; https://clinicaltrials.gov/ct2/show/NCT03262662.

Effect of Extending the Duration of Prequit Treatment With Varenicline on Smoking Abstinence: A Randomized Clinical Trial.

Importance: Even with varenicline, the leading monotherapy for tobacco dependence, smoking abstinence rates remain low. Preliminary evidence suggests that extending the duration of varenicline treatment before quitting may increase abstinence. Objective: To test the hypotheses that, compared with standard run-in varenicline treatment (1 week before quitting), extended run-in varenicline treatment (4 weeks before quitting) reduces smoking exposure before the target quit date (TQD) and enhances abstinence, particularly among women. Design, Setting, and Participants: This double-blind, randomized, placebo-controlled clinical trial enrolled participants from October 2, 2017, to December 9, 2020, at a single-site research clinic in Buffalo, New York. Of 1385 people screened, 320 adults reporting smoking 5 or more cigarettes per day (CPD) were randomized and followed up for 28 weeks. Data were analyzed from August 2021 to June 2022. Interventions: In the pre-TQD period (weeks 1-4), the extended run-in group received 4 weeks of varenicline; the standard run-in group received 3 weeks of placebo followed by 1 week of varenicline. Both groups received open-label varenicline during weeks 5 to 15 and brief quit counseling at 6 clinic visits. Main Outcomes and Measures: The primary outcome consisted of cotinine-verified (at end of treatment [EOT]) self-reported continuous abstinence from smoking (in CPD) during the last 4 weeks of treatment. Secondary outcomes included bioverified self-report of continuous abstinence at the 6-month follow-up and percentage of reduction in self-reported smoking rate during the prequit period (week 1 vs week 4). Results: A total of 320 participants were randomized, including 179 women (55.9%) and 141 men (44.1%), with a mean (SD) age of 53.7 (10.1) years. Continuous abstinence during the final 4 weeks of treatment (weeks 12-15; EOT) was not greater in the extended run-in group (64 of 163 [39.3%]) compared with the standard run-in group (57 of 157 [36.3%]; odds ratio [OR], 1.13 [95% CI, 0.72-1.78]), nor was the hypothesized group × sex interaction significant (OR, 0.52 [95% CI, 0.21-1.28]). Similar nonsignificant results were obtained for continuous abstinence at the 6-month follow-up. The mean (SE) decrease in self-reported smoking rate during the prequit period was greater in the extended run-in group (-38.8% [2.8%]) compared with the standard run-in group (-17.5% [2.7%]). Conclusions and Relevance: Among adult daily smokers, extending the duration of prequit varenicline treatment beyond the standard 1-week run-in period reduced prequit smoking exposure but, more importantly, did not significantly improve continuous abstinence rates. Trial Registration: ClinicalTrials.gov Identifier: NCT03262662.

A Psychometric Evaluation of the Stanford Expectations of Treatment Scale (SETS) in the Context of a Smoking Cessation Trial.

INTRODUCTION: Although treatment outcome expectancies (TOEs) may influence clinical outcomes, TOEs are rarely reported in the smoking cessation literature, in part because of the lack of validated measures. Therefore, we conducted a psychometric evaluation of TOEs scores with the Stanford Expectations of Treatment Scale (SETS) in the context of a smoking cessation clinical trial. METHODS: Participants were 320 adults enrolled in a randomized controlled trial of extended versus standard pre-quit varenicline treatment for smoking cessation (clinicaltrials.gov ID: NCT03262662). Across an 8-week treatment period, we examined the nature and stability of the factor structure using confirmatory factor analysis (CFA), evaluated discriminant validity by examining correlations with abstinence self-efficacy and positive/negative affect (PA/NA), and assessed internal consistency and test-retest reliability of SETS scores. RESULTS: CFAs supported a 2-factor structure that was stable (ie, invariant) across weeks. Positive and negative TOEs were each reflected in three-item subscales that exhibited acceptable to excellent internal consistency (Cronbach's alphas ≥ .77). Positive and negative TOEs were modestly correlated with PA and NA (all |rs| <.27, p < .05). Positive TOEs, but not negative TOEs, were moderately correlated with abstinence self-efficacy (rs = .45 to .61, p < .01). Both positive and negative TOEs scores demonstrated moderate test-retest reliability between assessments (rs = .54 to .72). CONCLUSIONS: SETS scores generally reflect a valid and reliable assessment of positive and negative TOEs in a sample of adults enrolled in a smoking cessation trial. The SETS appears to be a reasonable option for assessing TOEs in future smoking treatment studies. IMPLICATIONS: Assessments of treatment outcome expectancies are rarely reported in the smoking cessation literature. The present results support the validity and reliability of the SETS scores among adults seeking treatment for their smoking behavior.

Evaluating Treatment Mechanisms of Varenicline: Mediation by Affect and Craving.

INTRODUCTION: Negative reinforcement models posit that relapse to cigarette smoking is driven in part by changes in affect and craving during the quit attempt. Varenicline may aid cessation by attenuating these changes; however, this mediational pathway has not been formally evaluated in placebo-controlled trials. Thus, trajectories of negative affect (NA), positive affect (PA), and craving were tested as mediators of the effect of varenicline on smoking cessation. AIMS AND METHODS: Secondary data analysis was conducted on 828 adults assigned to either varenicline or placebo in a randomized controlled trial for smoking cessation (NCT01314001). Self-reported NA, PA, and craving were assessed 1-week pre-quit, on the target quit day (TQD), and 1 and 4 weeks post-TQD. RESULTS: Across time, NA peaked 1-week post-quit, PA did not change, and craving declined. Less steep rises in NA (indirect effect 95% CI: .01 to .30) and lower mean craving at 1-week post-quit (CI: .06 to .50) were mediators of the relationship between varenicline and higher cessation rates at the end of treatment. PA was associated with cessation but was not a significant mediator. CONCLUSIONS: These results partially support the hypothesis that varenicline improves smoking cessation rates by attenuating changes in specific psychological processes and supported NA and craving as plausible treatment mechanisms of varenicline. IMPLICATIONS: The present research provides the first evidence from a placebo-controlled randomized clinical trial that varenicline's efficacy is due, in part, to post-quit attenuation of NA and craving. Reducing NA across the quit attempt and craving early into the attempt may be important treatment mechanisms for effective interventions. Furthermore, post-quit NA, PA, and craving were all associated with relapse and represent treatment targets for future intervention development.

Stability of Varenicline Concentration in Saliva Over 21 Days at Three Storage Temperatures.

INTRODUCTION: Varenicline is the most efficacious drug for smoking cessation; saliva varenicline concentrations can be useful for the evaluation of adherence in smoking cessation trials. Saliva is a useful noninvasive matrix for mail-in specimen collection, if stable. We investigated the stability of varenicline in saliva at different storage temperatures simulating the time it takes to mail in a sample. METHODS: We evaluated the concentrations of varenicline, nicotine, cotinine, 3'-hydroxycotinine, and 3'-hydroxycotinine/cotinine (3HC/COT) ratio in quality control saliva samples (and after repeated freezing and thawing), and in smokers' saliva samples, stored for up to 21 days at room temperature (~25°C), 4°C, and -80°C. RESULTS: In saliva quality control samples, concentrations of varenicline, nicotine, cotinine, 3'-hydroxycotinine, and 3HC/COT remained unchanged and showed little within-sample variation (CV ≤ 5.5%) for up to 21 days at the three storage temperatures; they were also not altered after three thaw-freeze cycles. In smokers' saliva, a significant main effect of storage duration, but not temperature, was observed for varenicline, cotinine, and 3'-hydroxycotinine, but not for nicotine or the 3HC/COT ratio. However, these changes were within analytical (i.e., equipment) variation resulting in little within-sample variation (CV ≤ 5.8%) for all analytes in smokers' saliva. CONCLUSIONS: Varenicline, the other analytes, and the 3HC/COT ratio remained stable in saliva during storage for 21 days at all temperatures tested and after repeated freezing and thawing with only minor changes in concentration over time. These findings support the potential use of mail-in approach for saliva samples in varenicline smoking cessation clinical trials. IMPLICATIONS: Assessing saliva varenicline concentrations can be useful for the evaluation of adherence in smoking cessation trials. Saliva is a noninvasive matrix suitable for mail-in specimen collection. This is the first investigation of stability of varenicline in saliva. Varenicline, nicotine, cotinine, 3'-hydroxycotinine, and 3HC/COT were stable in saliva for up to 21 days at room temperature (~25°C), 4°C, and -80°C, supporting the use of a mail-in approach for saliva specimen in smoking cessation trials.

Transitioning to Remote Clinic Visits in a Smoking Cessation Trial During the COVID-19 Pandemic: Mixed Methods Evaluation.

BACKGROUND: The pandemic of SARS-CoV-2, which causes COVID-19, has caused disruptions in ongoing clinical trials and is expected to accelerate interest in conducting research studies remotely. OBJECTIVE: A quasi-experimental, mixed methods approach was used to examine the rates of visit completion as well as the opinions and experiences of participants enrolled in an ongoing clinical trial of smoking cessation who were required to change from in-person clinic visits to remote visits using video or telephone conferencing due to the COVID-19 pandemic. METHODS: For quantitative comparisons, we used a quasi-experimental design, comparing a cohort of participants followed during the pandemic (n=23, COVID-19 cohort) to a comparable cohort of participants followed over a similar time period in the calendar years 2018 and 2019 (n=51, pre-COVID-19 cohort) to examine the rates of completion of scheduled visits and biospecimen collection. For the qualitative component, interviews were conducted with participants who experienced the transition from in-person to remote visits. RESULTS: Participants in the COVID-19 cohort completed an average of 83.6% of remote clinic visits (95% CI 73.1%-91.2%), which was not significantly different than the in-person completion rate of 89.8% in the pre-COVID-19 cohort. Participants in the COVID-19 cohort returned an average of 93.2% (95% CI 83.5%-98.1%) of saliva specimens for remote clinic visits completed, which was not significantly different than the in-person saliva specimen completion rate of 100% in the pre-COVID-19 cohort. Two broad themes emerged from the qualitative data: (1) the benefits of remote visits and (2) the challenges of remote counseling compared to in-person counseling. Despite limited experience with telehealth prior to this transition, most participants expressed a willingness to engage in remote visits in the future. CONCLUSIONS: Even in the context of a rapid transition from in-person to remote visits necessitated by the COVID-19 pandemic, rates of visit completion and return of biospecimens remained high. Participants were generally accepting of the transition. Further research is needed to identify the optimal mix of in-person and remote visits beyond the pandemic context and to better understand how these changes may impact study outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT03262662; https://clinicaltrials.gov/ct2/show/study/NCT03262662.

The impact of three weeks of pre-quit varenicline on reinforcing value and craving for cigarettes in a laboratory choice procedure.

RATIONALE: Varenicline, a partial nicotinic agonist, is theorized to attenuate pre-quit smoking reinforcement and post-quit withdrawal and craving. However, the mechanisms of action have not been fully characterized, as most studies employ only retrospective self-report measures, hypothetical indices of reinforcing value, and/or nontreatment-seeking samples. OBJECTIVES: The current research examined the impact of pre-quit varenicline (vs. placebo) on laboratory measures of smoking and food (vs. water) reinforcement and craving. METHODS: Participants were 162 treatment-seeking smokers enrolled in a randomized controlled trial of smoking cessation ( clinicaltrials.gov ID: NCT03262662). Participants completed two laboratory sessions: a pre-treatment session, ~ 1 week prior to beginning varenicline or placebo, and an active treatment session, after ~ 3 weeks of treatment. At each session, participants completed a laboratory choice procedure; on each of 36 trials, a lit cigarette, food item, or cup of water was randomly presented. Participants reported level of craving and spent $0.01-0.25 to have a corresponding 5-95% chance to sample the cue. RESULTS: As predicted, spending was significantly higher on cigarette trials than water trials, and varenicline resulted in a greater between-session decline in spending on cigarette trials (but not water) than did placebo. Cigarette craving was enhanced in the presence of smoking cues compared to water, but neither average (tonic) cigarette craving nor cue-specific cigarette craving was significantly influenced by varenicline. Food spending and craving were generally unaffected by varenicline treatment. CONCLUSIONS: These laboratory data from treatment-seeking smokers provide the strongest evidence to date that varenicline selectively attenuates smoking reinforcement prior to quitting.

Patterns of lapses and recoveries during a quit attempt using varenicline and behavioral counseling among smokers with and without HIV.

Addressing tobacco use among HIV+ smokers is a priority. Lack of knowledge about how HIV+ smokers respond to tobacco use treatments limits our ability to effectively treat this population of smokers. Using data from 2 clinical trials that provided 12 weeks of varenicline and behavioral counseling, 1 with smokers with HIV (n = 89) and 1 with smokers without HIV (n = 179), we used mixed logistic regression modeling to compare point-prevalence abstinence rates and adherence to the initial target quit date (TQD) and Cox regression for repeated outcomes to evaluate lapse and recovery dynamics between the groups. Sixty percent of HIV- smokers refrained from smoking at the TQD while only 33% of HIV+ smokers did (odds ratio [OR] = 0.32, 95% CI [0.18, 0.56], p < .001). The point-prevalence abstinence rates at Week 12 were 31% (HIV-) and 28% (HIV+; OR = 0.7, 95% CI [0.42, 1.16], p = .16) and the point prevalence abstinence rates at Week 24 were 22% (HIV-) and 15% (HIV+; OR = 0.87, 95% CI [0.49, 1.57], p = .65). Although there was no interaction between HIV status and lapse risk, χ2(3) < 1, there was a significant interaction for the recovery model, (χ2(3) = 20.4, p < 0.001): as the number of events increased, the time to the next recovery became longer among smokers with HIV, compared to smokers without HIV. Although HIV+ smokers were treated effectively with varenicline, compared to HIV- smokers, they showed significantly lower initial cessation at the TQD and took increasingly longer to recover following lapses. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Making lemonade from SARS coronavirus-2 lemons: Transitioning a smoking cessation trial to a virtual platform.

Clinical trials represent an essential component of improving treatment for substance use disorders (SUD). The SARS coronavirus-2 pandemic disrupted our ongoing clinical trial of smoking cessation and forced us to rapidly implement changes to assure participants access to ongoing counseling and monitoring via telephone calls and/or video chat sessions. Our experiences suggest that this pandemic will lead to changes for both future clinical trial participants and project staff. While challenges remain, it will be important to assessing the impact of these changes with regard to participant experiences and treatment outcomes.

Evaluation of nicotine patch adherence measurement using self-report and saliva cotinine among abstainers in a smoking cessation trial.

BACKGROUND: Adherence to nicotine patches relates to cessation. This is the first study to examine the validity of self-reported nicotine patch adherence relative to saliva cotinine. METHODS: We used data from 198 clinical trial participants who received 11 weeks of nicotine patches, self-reported patch use, had saliva cotinine 1-week after the start of treatment assessed, and were not smoking when saliva was collected (CO < 6). Self-reported patch adherence was defined as: 3-day (before saliva collection), 7-day (before saliva collection), 3-week use (7 days before, and 14 days after, saliva collection), and 11-week use (7 days before, and 10 weeks after, saliva collection). Analyses, including receiver operating characteristic curves, considered differences in nicotine metabolism. Sensitivity, specificity and positive (PPV) and negative predictive value (NPV) assessed optimal cotinine cut-point for adherence. RESULTS: Self-reported 7-day (r = 0.13) and 3-week (r = 0.13) patch use marginally correlated with week 1 cotinine (p's = 0.08) but not 3-day or 11-week. Significant area under the curve (AUC) values of 0.67 (95 %CI: 0.55-0.79) and 0.72 (95 %CI: 0.57-0.88) were found using 7-day self-report for the overall sample and for slow metabolizers (p's<0.01), but not for normal metabolizers. Optimal 1-week cotinine cut-points using 7-day self-report were 170 ng/mL (overall) and 184 ng/mL (slow), with sensitivity = 0.56-0.62, specificity = 0.69-0.78, PPV = 0.96-0.97, and NPV = 0.13-0.14. CONCLUSIONS: Among CO-confirmed abstainers, self-reported patch use and saliva cotinine assessed 1-week into treatment, were modestly correlated and optimal cotinine cut-point differed by rate of nicotine metabolism. Seven-day patch use may be a more valid self-report measure of patch adherence based on cotinine than 3-day, 3-week, or 11-week. Rate of nicotine metabolism may affect this relationship.

Withdrawal Symptom, Treatment Mechanism, and/or Side Effect? Developing an Explicit Measurement Model for Smoking Cessation Research.

INTRODUCTION: Assessment of withdrawal symptoms, treatment mechanisms, and side effects is central to understanding and improving smoking cessation interventions. Though each domain is typically assessed separately with widely used questionnaires to separately assess each domain (eg, Minnesota Nicotine Withdrawal Scale = withdrawal; Questionnaire of Smoking Urges-Brief = craving; Positive and Negative Affect Schedule = affect; symptom checklist = side effects), there are substantial problems with this implicit "one questionnaire equals one construct" measurement model, including item overlap across questionnaires. This study sought to clarify the number and nature of constructs assessed during smoking cessation by developing an explicit measurement model. METHODS: Two subsamples were randomly created from 1246 smokers in a clinical trial. Exploratory and confirmatory factor analyses were conducted to identify and select a model that best represented the data. Measurement invariance was assessed to determine if the factors and their content were consistent prior to and during the quit. Improvement in construct overlap within this model was compared against the implicit measurement model using correlational analyses. RESULTS: A 5-factor measurement model composed of negative affect, somatic symptoms, sleep problems, positive affect, and craving fits the data well prior to and during quitting. All factor content except somatic symptoms was consistent over time. Correlational analyses indicated that the 5-factor model attenuated construct overlap compared to the implicit model. CONCLUSIONS: The models generated from data-driven approaches (eg, the 5-factor model) reduced overlap and better represented the constructs underlying these measures. This approach created distinct, stable constructs that span over measures of side effects and potential treatment mechanisms. IMPLICATIONS: This study demonstrated that measures assessing treatment mechanisms, withdrawal symptoms, and side effects contain problematic overlap that reduces the clarity of these key constructs. The use of data-driven approaches showed that these measures do not map on to their posited latent constructs (eg, the Minnesota Nicotine Withdrawal Scale does not yield a withdrawal factor). Rather, these measures form distinct, basic processes that may represent more meaningful constructs for future research on cessation and treatment. Assessments designed to individually examine these processes may improve the study of treatment mechanisms.

Evaluating the temporal relationships between withdrawal symptoms and smoking relapse.

Smokers attempting to quit often attribute smoking relapse to negative affect, craving, and other nicotine withdrawal symptoms. In addition, there is evidence that smoking relapse can increase these symptoms, particularly negative affect. To address this issue, we analyzed data from an 11-week smoking cessation clinical trial in which smokers (n = 1,246) were randomized to receive either nicotine replacement therapy (NRT), varenicline, or placebo, combined with behavioral counseling. Using cross-lagged analyses, we examined the temporal bidirectional relationships between self-reported measures of affect, craving, and composite withdrawal symptoms and biochemically verified smoking abstinence. The relative strength of these temporal relationships was examined by comparing the explained variances of the models. The results showed that higher negative affect, craving, and composite withdrawal symptoms increased the likelihood of subsequent smoking relapse, and that smoking relapse led to subsequent increases in these same symptoms. A comparison of the explained variances found symptom predicting subsequent relapse models to be stronger than those where relapse predicted subsequent symptoms. Although the explained variance findings generally support a negative reinforcement conceptualization of nicotine dependence, the bidirectional relationship between symptoms and smoking relapse suggests that struggling with quitting smoking leads to significant negative affect, craving, and other withdrawal symptoms that do not quickly resolve. These findings highlight the importance of addressing specific symptoms within the context of smoking cessation. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Predicting smoking abstinence with biological and self-report measures of adherence to varenicline: Impact on pharmacogenetic trial outcomes.

INTRODUCTION: Adherence to pharmacotherapies for tobacco dependence, such as varenicline, is necessary for effective treatment. The relationship between varenicline adherence, determined by commonly used indirect (i.e., self-reported pill counts) and infrequently used direct (i.e., varenicline levels) methods, and abstinence outcomes have not been previously examined, nor has their impact on the outcomes of a genetically randomized clinical trial been assessed. METHODS: At Week 1 following target quit date, self-reported pill count and salivary varenicline levels were obtained from participants (N = 376) in a smoking cessation clinical trial (NCT01314001). Point-prevalence abstinence was biochemically-verified by salivary cotinine at Week 1 and by exhaled carbon monoxide at Week 1, end-of-treatment, 6 and 12 months following treatment. Blood nicotine metabolite ratio (NMR) was obtained at baseline. RESULTS: Adherent individuals based on varenicline levels were significantly more likely to be abstinent than non-adherent individuals at Week 1 (odds ratios [ORs] 1.92-3.16, p's≤0.006), end-of-treatment (OR = 2.53, p = .004), and six months following treatment (OR = 2.30, p = .03). In contrast, pill counts did not consistently predict abstinence. Including direct measures of adherence enhanced the association between rate of nicotine metabolism (NMR) and end-of-treatment abstinence; normal metabolizers (NMR ≥ 0.31) were significantly more likely than slow metabolizers (NMR < 0.31) to be abstinent at end-of-treatment (OR = 2.00, p = .005). CONCLUSION: Adherence based on salivary varenicline, rather than on pill counts, is predictive of Week 1 abstinence, irrespective of the biomarker of abstinence assessed, and of long-term abstinence. Direct measures of adherence enhance the ability to assess the impact of a biomarker or genetic marker on abstinence outcomes.

Social reinforcement as alternative to sucrose reinforcement is increased by nicotine and methylphenidate in male Fischer-344 rats.

BACKGROUND: Stimulant drugs such as nicotine (NIC) and methylphenidate (MPH) are hypothesized to increase the reinforcing value of sensory stimuli, thus increasing the effectiveness of such reinforcers as alternatives to sucrose reinforcers. METHODS: Inbred Fischer-344 rats (n = 30) were assigned to three groups: saline (SAL; n = 10), nicotine (NIC; n = 10), or methylphenidate (MPH; n = 10). Testing was done in three phases: sucrose only, (SUC), sucrose and drug (SUC/DRUG), and sucrose, drug, and social reinforcement (SUC/DRUG/SOC). During the SUC phase, rats were trained on a progressive ratio 5 (PR5) reinforcement schedule for sucrose (20% solution). In the SUC/DRUG phase, animals were treated with SAL, NIC (0.4 mg/kg, n = 10 SC), or MPH (2.0 mg/kg, n = 10 IP) 30 min prior to testing. In the SUC/DRUG/SOC phase, animals continued receiving drug treatment, and social reinforcement was introduced concurrently with the sucrose reinforcer. The progressive ratio for each reinforcer ran independently of the others. Reinforcing value was measured as break point (BP), the highest number of responses resulting in a reinforcer. RESULTS: SAL-treated animals showed no significant change in sucrose BP. MPH-treated animals showed decreased sucrose BP in the SUC/DRUG phase, with a further reduction in the SUC/DRUG/SOC phase. NIC-treated animals decreased sucrose BP only when a social alternative was offered. CONCLUSION: Both NIC and MPH reduce the sucrose BP in the presence of a social alternative. The decrease in sucrose responding, coupled with increased social responding, suggests that the social alternative acted as an effective alternative reinforcer to sucrose. From a translational perspective, these results suggest that stimulant drugs such as NIC and MPH may increase the effectiveness of treatments that use alternative social reinforcers to decrease eating.

Genome-wide association study of a nicotine metabolism biomarker in African American smokers: impact of chromosome 19 genetic influences.

BACKGROUND AND AIMS: The activity of CYP2A6, the major nicotine-inactivating enzyme, is measurable in smokers using the nicotine metabolite ratio (NMR; 3'hydroxycotinine/cotinine). Due to its role in nicotine clearance, the NMR is associated with smoking behaviours and response to pharmacotherapies. The NMR is highly heritable (~80%), and on average lower in African Americans (AA) versus whites. We previously identified several reduce and loss-of-function CYP2A6 variants common in individuals of African descent. Our current aim was to identify novel genetic influences on the NMR in AA smokers using genome-wide approaches. DESIGN: Genome-wide association study (GWAS). SETTING: Multiple sites within Canada and the United States. PARTICIPANTS: AA smokers from two clinical trials: Pharmacogenetics of Nicotine Addiction Treatment (PNAT)-2 (NCT01314001; n = 504) and Kick-it-at-Swope (KIS)-3 (NCT00666978; n = 450). MEASUREMENTS: Genome-wide SNP genotyping, the NMR (phenotype) and population substructure and NMR covariates. FINDINGS: Meta-analysis revealed three independent chromosome 19 signals (rs12459249, rs111645190 and rs185430475) associated with the NMR. The top overall hit, rs12459249 (P = 1.47e-39; beta = 0.59 per C (versus T) allele, SE = 0.045), located ~9.5 kb 3' of CYP2A6, remained genome-wide significant after controlling for the common (~10% in AA) non-functional CYP2A6*17 allele. In contrast, rs111645190 and rs185430475 were not genome-wide significant when controlling for CYP2A6*17. In total, 96 signals associated with the NMR were identified; many were not found in prior NMR GWASs in individuals of European descent. The top hits were also associated with the NMR in a third cohort of AA (KIS2; n = 480). None of the hits were in UGT or OCT2 genes. CONCLUSIONS: Three independent chromosome 19 signals account for ~20% of the variability in the nicotine metabolite ratio in African American smokers. The hits identified may contribute to inter-ethnic variability in nicotine metabolism, smoking behaviours and tobacco-related disease risk.