Smoking Craving Research Articles

Regulation of craving for real-time fMRI neurofeedback based on individual classification.

In previous real-time functional magnetic resonance imaging neurofeedback (rtfMRI-NF) studies on smoking craving, the focus has been on within-region activity or between-region connectivity, neglecting the potential predictive utility of broader network activity. Moreover, there is debate over the use and relative predictive power of individual-specific and group-level classifiers. This study aims to further advance rtfMRI-NF for substance use disorders by using whole-brain rtfMRI-NF to assess smoking craving-related brain patterns, evaluate the performance of group-level or individual-level classification (n = 31) and evaluate the performance of an optimized classifier across repeated NF runs. Using real-time individual-level classifiers derived from whole-brain support vector machines, we found that classification accuracy between crave and no-crave conditions and between repeated NF runs increased across repeated runs at both individual and group levels. In addition, individual-level accuracy was significantly greater than group-level accuracy, highlighting the potential increased utility of an individually trained whole-brain classifier for volitional control over brain patterns to regulate smoking craving. This study provides evidence supporting the feasibility of using whole-brain rtfMRI-NF to modulate smoking craving-related brain responses and the potential for learning individual strategies through optimization across repeated feedback runs. This article is part of the theme issue 'Neurofeedback: new territories and neurocognitive mechanisms of endogenous neuromodulation'.

7625 Functional and structural neuronal changes of dulaglutide compared to placebo during smoking cessation - a randomized placebo-controlled trial

Abstract Disclosure: C.O. Sailer: None. S. Lengsfeld: None. D. Coynel: None. F. Baur: None. K. Bologna: None. T. Vukajlovic: None. N.A. Jeanloz: None. C. Bathelt: None. D. Zanchi: None. M. Christ-Crain: None. B.F. Winzeler: None. Introduction: Nicotine activates reward-related brain regions and chronic cigarette smoking can lead to functional and structural neuronal changes. Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs), known for their anti-obesity effects, have emerged as potential treatments for addictive disorders. A pilot study of exenatide vs placebo revealed increased short-term smoking abstinence rates and reduce smoking craving. We previously reported the results of a clinical trial (n=255) investigating the effect of dulaglutide vs placebo on smoking cessation. Herein, we report the functional magnetic resonance imaging (fMRI) results of a subset of participants. This substudy aimed to investigate the influence of dulaglutide on smoking craving, functional and structural neuronal changes of smokers aiming to quit smoking. Methods: This single-center, randomized, double-blind, placebo-controlled trial enrolled 71 participants with at least a moderate nicotine dependence, all committed to quitting smoking. Of these, 35 participants received 12 weeks dulaglutide 1.5mg, and 36 participants placebo, alongside varenicline treatment and behavioral counselling. An fMRI session was conducted at baseline and 12 weeks. The primary outcomes included smoking craving assessed on a visual analogue scale (VAS, range 0-7), differences in blood oxygen level dependent (BOLD) signal (whole brain and regions of interests, e.g., nucleus accumbens, amygdala, thalamus) and gray matter changes between sessions and groups when exposed to smoking and neutral video cues. Secondary outcomes assessed the above in quitters vs persistent smokers. Results: In line with the primary study findings, abstinence rates at 12 weeks were comparable in the dulaglutide (54%) and placebo (68%) groups (p=0.27). In a mixed effect model, smoking craving significantly decreased at 12 weeks vs baseline (-2.13 (95% CI -2.46, -1.80), p<0.001) and were lower for neutral vs smoking cues (-2.02 (-2.34, 1.70,), p<0.001). However, no significant inter-group difference was observed (-0.09 (-0.53, 0.33), p=0.65). Persistent smokers exhibited higher smoking craving at 12 weeks vs quitters (0.48 (0.06, 0.90), p=0.028), particularly when exposed to smoking cues (2.02 (1.70, 2.34), p<0.001). No significant differences were found in functional or structural analyses between interventions or smoking status. Conclusions: The smoking cessation intervention led to a significant reduction in smoking craving at 12 weeks without in-between group differences in behavioral, functional, or structural outcomes. Our findings challenge the hypothesis that GLP-1 RAs modulates smoking craving and behavior. It is plausible that a potential GLP-1 effect might have been masked by varenicline treatment and the unexpectedly high abstinence rate in the placebo group. Future studies should explore more potent GLP-1 RAs or dual agonists. Presentation: 6/1/2024

Repetitive transcranial magnetic stimulation reshaped the dynamic reconfiguration of the executive and reward networks in individuals with tobacco use disorder

BackgroundStudies have demonstrated the potential of repetitive transcranial magnetic stimulation (rTMS) to decrease smoking cravings in individuals with tobacco use disorder (TUD). However, the neural features underlying the effects of rTMS treatment, especially the dynamic attributes of brain networks associated with the treatment, remain unclear. MethodsUsing dynamic functional connectivity analysis, this study first explored the differences in dynamic functional network features between 60 subjects with TUD and 64 nonsmoking healthy controls (HCs). Then, the left dorsolateral prefrontal cortex (DLPFC) was targeted for a five-day course of rTMS treatment in the 60 subjects with TUD (active rTMS in 42 subjects and sham treatment in 18 subjects). We explored the effect of rTMS on the dynamic network features associated with rTMS by comparing the actively treated group and the sham group. ResultsCompared to nonsmokers, TUD subjects exhibited an increased integration coefficient between the frontoparietal network (FPN) and the basal ganglia network (BGN) and a reduced integration coefficient between the medial frontal network (MFN) and the FPN. Analysis of variance revealed that rTMS treatment reduced the integration coefficient between the FPN and BGN and improved the recruitment coefficient of the FPN. LimitationsThis study involved a limited sample of young male smokers, and the findings may not generalize to older smokers or female smokers with an extensive history of smoking. ConclusionrTMS treatment of the left DLPFC exhibited significant effectiveness in restructuring the neural circuits associated with TUD while significantly mitigating smoking cravings.

The Development and Validation of a Scale to Understand Smoking Cessation Efforts Among Middle-Aged Male Workers

The purpose of this study was to develop and test the reliability and validity of a scale assessing the efforts made by midlife adult male smokers to quit smoking. The draft of the scale, designated the Smoking Cessation Assessment of Progress Scale (SCAPS), was developed a qualitative inductive analysis of the characteristics of successful smoking cessation efforts among midlife adult male workers in a previous study by the authors. The subjects were men in their 30s and 40s who were employed, had quit smoking for at least six months, and who had succeeded in quitting without seeking outpatient smoking cessation treatment. After a preliminary survey, the main survey was conducted. Data was analyzed using the maximum likelihood Promax rotation method. Confirmatory factor analysis was subsequently conducted, resulting in the identification of three factors and 17 items. The factors identified were "response to smoking cravings," "perceived benefits associated with successful smoking cessation," and "positive perception of smoking cessation. Cronbach's alpha coefficients for each subscale ranged from 0.702 to 0.873, which were generally favorable. Construct validity was generally ensured by confirmatory factor analysis and the estimates extracted from the results for each factor. The reliability and validity of SCAPS were generally verified.

RTMS effects on urges and severity of tobacco use disorder operate independently of a retrieval-extinction component and involve frontal-striatal pathways

BackgroundAlthough smoking remains a leading cause of preventable disease, the treatment options for smoking are limited. The present study evaluated the neural features underlying effects of repetitive transcranial magnetic stimulation (rTMS) for reducing smoking cravings. In addition, the efficacy of a simulated retrieval-extinction procedure to augment rTMS efficacy was examined. MethodsSixty-one individuals with tobacco use disorder (TUD) were randomized into three groups: classic rTMS, retrieval rTMS (viewed smoking videos before rTMS), and sham rTMS. rTMS was performed on the left dorsolateral prefrontal cortex (DLPFC) over 5 days using a standard figure-8 coil. Smoking cravings and brain responses to smoking cues were measured before and after rTMS treatment. Changes in functional connectivity (FC) among different brain regions were calculated. ResultsrTMS reduced smoking urges in TUD. Both active-rTMS groups demonstrated greater activations of the DLPFC, caudate, and bilateral insula relative to the sham group. Increased FC was observed between executive and reward network brain regions, and decreased FC was observed within reward network regions. Compared with standard rTMS, retrieval-extinction rTMS demonstrated similar outcomes and was associated with less activation of the medial frontal gyrus. ConclusionsrTMS increased activations in brain regions implicated in executive control and reward processing. Strengthened prefrontal–striatal pathway suggests that rTMS enhanced top-down control over smoking cravings. The retrieval–extinction process, although associated with some different and multiple similar neural correlates as the standard rTMS, did not enhance cessation outcomes.

Foods and beverages associated with smoking craving in heated tobacco product and cigarette smokers: A cross-sectional study.

Certain foods and beverages are associated with smoking craving. However, only few studies have explored the relationship between food or beverage-related and taste-associated smoking craving. In this study, we aimed to identify the types of foods related to smoking craving in Japanese individuals who smoke cigarettes or heated tobacco products (HTPs). A total of 657 individuals (HTP and cigarette smokers and never smokers) participated in this cross-sectional study. Participants were asked what foods/beverages, tastes, seasonings, cooking methods, and cuisine categories, made them want to smoke and what foods they consumed. Alcoholic beverages such as beer, coffee, and fat-rich foods were associated with a higher likelihood of smoking craving. Fruits, dairy products such as milk, and sweet and sour tastes, were associated with a lower likelihood of smoking craving. The daily intake of fruit and dairy products was significantly lower in cigarette and HTP smokers than in non-smokers (median fruit intake: non-smokers, 46.4 g/1000 kcal/day; cigarette smokers, 22.2 g/1000 kcal/day; HTP smokers, 31.4 g/1000 kcal/day; p<0.001; median dairy product intake: non-smokers, 76.3 g/day; cigarette smokers, 48.2 g/day; HTP smokers, 57.6 g/day; p<0.001) as assessed using a food frequency questionnaire (BDHQ). Specific foods and beverages such as alcohol, fruits, and dairy products are related to smoking craving, and their intake differs according to smoking status.

Exploring the therapeutic potential of tDCS, TMS and DBS in overcoming tobacco use disorder: an umbrella review

&lt;p&gt;The purpose of the present study was to investigate the effects of neuromodulation techniques, including transcranial direct current stimulation, transcranial magnetic stimulation, and deep brain stimulation, on the treatments of nicotine dependence. Specifically, our objective was to assess the existing evidence by conducting an umbrella review of systematic reviews. The quality of the included studies was evaluated using the standardized tools designed to evaluate systematic reviews. The PubMed/MEDLINE database was queried for systematic reviews, and yielded 7 systematic reviews with a substantial sample size (N = 4,252), some of which included meta-analyses. A significant finding across these studies was the effectiveness of neuromodulation techniques to reduce nicotine cravings and consumption, through the evidence remains not yet conclusive. A significant efficacy of transcranial direct current stimulation and repetitive transcranial magnetic stimulation that targeted the dorsolateral prefrontal cortex was found, as well as the lateral prefrontal cortex and insula bilaterally, on smoking frequency and craving. Moreover, smoking behaviors may also be positively affected by the use of deep brain stimulation (DBS) targeting the nucleus accumbens. In conclusion, neuromodulation approaches hold promise as effective treatments for tobacco use disorder. Nonetheless, further research is required to comprehensively understand their effectiveness and to determine if combining them with other treatments can aid individuals to successfully quit smoking.&lt;/p&gt;

Modulation of High‐Frequency rTMS on Reward Circuitry in Individuals with Nicotine Dependence: A Preliminary fMRI Study

Although previous studies have shown that repetitive transcranial magnetic stimulation (rTMS) can ameliorate addictive behaviors and cravings, the underlying neural mechanisms remain unclear. This study aimed to investigate the effect of high‐frequency rTMS with the left dorsolateral prefrontal cortex (L‐DLPFC) as a target region on smoking addiction in nicotine‐dependent individuals by detecting the change of spontaneous brain activity in the reward circuitry. We recruited 17 nicotine‐dependence participants, who completed 10 sessions of 10 Hz rTMS over a 2‐week period and underwent evaluation of several dependence‐related scales, and resting‐state fMRI scan before and after the treatment. Functional connectivity (FC) analysis was conducted with reward‐related brain regions as seeds, including ventral tegmental area, bilateral nucleus accumbens (NAc), bilateral DLPFC, and bilateral amygdala. We found that, after the treatment, individuals showed reduced nicotine dependence, alleviated tobacco withdrawal symptoms, and diminished smoking cravings. The right NAc showed increased FC with right fusiform gyrus, inferior temporal gyrus (ITG), calcarine fissure and surrounding cortex, superior occipital gyrus (SOG), lingual gyrus, and bilateral cuneus. No significant FC changes were observed in other seed regions. Moreover, the changes in FC between the right NAc and the right ITG as well as SOG before and after rTMS were negatively correlated with changes in smoking scale scores. Our findings suggest that high‐frequency L‐DLPFC‐rTMS reduces nicotine dependence and improves tobacco withdrawal symptoms, and the dysfunctional connectivity in reward circuitry may be the underlying neural mechanism for nicotine addiction and its therapeutic target.

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

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. 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 (one 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). 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. The present data do not support that smoking reinforcement or craving is related to nicotine metabolism among individuals seeking to quit smoking. 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.

Attentional bias modification in male college smokers: The changes of facilitated attention, difficulty in disengagement and the transfer effects of training

BackgroundAttentional bias modification (ABM) has been used to modify the attentional bias (AB) towards smoking-related cues. Still, the effects of ABM are extensively controversial. The present study aimed to investigate the effects of ABM on AB and its two sub-processes named facilitated attention and difficulty in disengagement at two different stimulus durations, as well as test whether the effects of ABM could transfer to new measures of AB. MethodForty-six male college smokers were allocated to either ABM group using a modified visual probe task (n = 24), or the corresponding placebo training (PT) group (n = 22). Participants performed three sessions of training in one week. The pre- and post-training AB and its sub-processes were measured using visual probe task. Cue-target task and pictorial Stroop task were used for testing the transfer effects of ABM. ResultsThe AB in ABM group was significantly decreased compared with the PT group. Specifically, the facilitated attention was significantly reduced at 200 ms stimulus duration, while the difficulty in disengagement was significantly decreased at 500 ms stimulus duration. The benefit of ABM training could transfer to the cue-target task, but not to the pictorial Stroop task. Meanwhile, no effects of ABM were observed on smoking craving and nicotine dependence. ConclusionsThese findings suggested that the stimulus duration is a crucial factor for the efficacy of ABM on the facilitated attention and the difficulty in disengagement in male college smokers and detected the transfer effects between different measures of AB to some extent. Future studies need to further explore the influence mechanism in distinct stimulus durations.

The changes of intrinsic connectivity contrast in young smokers.

Previous studies demonstrated that reward circuit plays an important role in smoking. The differences of functional and structural connectivity were found among several brain regions such as thalamus and frontal lobe. However, few studies focused on functional connectivity (FC) in whole-brain voxel level of young smokers. In this study, intrinsic connectivity contrast (ICC) was used to perform voxel-based whole-brain analyses in 55 young smokers and 55 matched non-smokers to identify brain regions with significant group differences. ICC results showed that the connectivity of young smokers in medial frontal cortex (MedFC), supramarginal gyrus anterior division left (L_aSMG), central opercular cortex left (L_CO) and middle frontal gyrus left (L_MidFG) showed a significantly lower trend compared with the non-smokers. The seed-based FC analysis about MedFC indicated that young smokers showed reduced connectivity between the MedFC and left hippocampus, left amygdala compared to non-smokers. Correlation analysis showed that the ICC of MedFC in young smokers was significantly negatively correlated with Fagerstrom test for nicotine dependence (FTND) and Questionnaire on Smoking Urges (QSU). The FC between the MedFC and left hippocampus, left amygdala was significantly negatively correlated with Pack_years. The mediation analysis indicated that ICC of MedFC completely mediated FTND and QSU of young smokers. The results suggest that nicotine accumulation may affect the communication of the frontal lobe with the whole brain to some extent, leading to changes in smoking cravings. The above research also provides in-depth insights into the mechanism of adolescent smoking addiction and related intervention treatment.

Modulation of smoker brain activity and functional connectivity by tDCS: A go/no-go task-state fMRI study

BackgroundTranscranial direct current stimulation (tDCS) applied to particular brain areas may reduce a smoker's smoking cravings. Most studies on tDCS mechanisms are performed on brains in the resting state. Therefore, brain activity changes induced by tDCS during tasks need to be further studied. MethodsForty-six male smokers were randomised to receive anodal tDCS of the left/right dorsolateral prefrontal cortex (DLPFC) or sham tDCS. A go/no-go task was performed before and after stimulation, respectively. Brain activity and functional connectivity (FC) changes during the task state before and after tDCS were used for comparison. ResultsThis study revealed that the anodal stimulation over one DLPFC area caused decreased activity in the ipsilateral precuneus during the go task state. Right DLPFC stimulation increased the FC between the bilateral DLPFCs and the right anterior cingulate cortex (ACC), which is closely associated with cognition and inhibition of executive functions. Additionally, the study showed variations in brain activity depending on whether the anode was positioned over the right or left DLPFC (R-DLPFC or L-DLPFC). ConclusionDuring the go task, tDCS might exert a suppressive effect on some brain areas, such as the precuneus. Stimulation on the R-DLPFC might strengthen the FC between the right ACC and the bilateral DLPFCs, which could enhance the ability of behavioural decision-making and inhibition to solve conflicts effectively. Stimulating the L-DLPFC alone could increase the FC of bilateral DLPFCs with some brain regions associated with response inhibition.

평가적 조건화가 흡연자의 담배에 대한 태도에 미치는 영향

This study aimed to investigate the effects of Evaluative Conditioning (EC) intervention techniques on smoking cessation intentions and changes in both implicit and explicit attitudes towards smoking. EC involves repeatedly associating target stimuli with emotional stimuli to induce automatic attitude transformations. Participants (n=52) were randomly assigned to one of three groups: Positive Evaluation Conditioning (PEC), Negative Evaluation Conditioning (NEC), or Neutral Evaluation Conditioning (NC). The treatments involved establishing associations between emotional stimuli and smoking or smoking cessation stimuli. After the interventions, participants completed self-report questionnaires and a single target implicit association task to assess their attitudes. The results demonstrated a significant reduction in smoking cravings and positive attitudes towards smoking among participants who received negative evaluation conditioning training(time x group interaction effect, F=3.19, p&lt;.05; F=3.30, p&lt;.05.). These findings indicate that EC techniques effectively facilitate changes in automatic and implicit attitudes, which are influential factors in smoking behavior.

Menstrual cycle influences on cue-induced smoking cravings and heart rate variability.

Women experience greater difficulties in quitting smoking than men, though the hormonal factors contributing to this sex difference remain to be clarified. The current study aimed to examine menstrual cycle effects on smoking cue-induced cravings as well as examine dynamic reproductive hormone change as a potential mediator underlying any cycle effects observed. Twenty-one women who smoke underwent two laboratory sessions - one in the mid-follicular phase and the other in the late luteal phase - involving an in-vivo smoking cue task, administered before and after exposure to a psychosocial laboratory stressor. Heart rate variability (HRV) and subjective smoking cravings were assessed in response to the cue task. The degree of change in the urinary metabolites of estradiol and progesterone from 2 days before to the day of each laboratory session was measured. Results revealed that both before and following exposure to psychosocial stress, highly nicotine-dependent women exhibited smaller cue-induced increases in HRV relative to the follicular phase. In contrast, less nicotine-dependent women exhibit an increase in HRV in both menstrual cycle phases. Results furthermore suggest that menstrual cycle effects seen in highly nicotine-dependent women are driven by the decline in estradiol and progesterone occurring in the late luteal phase. Though limited by a small sample size, this study suggests that withdrawal from reproductive hormones in the late luteal phase may alter highly nicotine-dependent women's physiological response to smoking cues, which may reflect greater difficulty resisting temptation. These findings may provide some insight regarding women's greater difficulty in maintaining abstinence after quitting smoking.

Efficacy of a novel online integrated treatment for problem gambling and tobacco smoking: Results of a randomized controlled trial.

Problem gambling and tobacco use are highly comorbid among adults. However, there are few treatment frameworks that target both gambling and tobacco use simultaneously (i.e., an integrated approach), while also being accessible and evidence-based. The aim of this two-arm open label RCT was to examine the efficacy of an integrated online treatment for problem gambling and tobacco use. A sample of 209 participants (Mage = 37.66, SD = 13.81; 62.2% female) from North America were randomized into one of two treatment conditions (integrated [n = 91] or gambling only [n = 118]) that lasted for eight weeks and consisted of seven online modules. Participants completed assessments at baseline, after treatment completion, and at 24-week follow-up. While a priori planned generalized linear mixed models showed no condition differences on primary (gambling days, money spent, time spent) and secondary outcomes, both conditions did appear to significantly reduce problem gambling and smoking behaviours over time. Post hoc analyses showed that reductions in smoking and gambling craving were correlated with reductions in days spent gambling, as well as with gambling disorder symptoms. Relatively high (versus low) nicotine replacement therapy use was associated with greater reductions in gambling behaviours in the integrated treatment condition. While our open label RCT does not support a clear benefit of integrated treatment, findings suggest that changes in smoking and gambling were correlated over time, regardless of treatment condition, suggesting that more research on mechanisms of smoking outcomes in the context of gambling treatment may be relevant.

Effects of psychoeducation combined with transcranial direct current stimulation on reducing cigarette craving and consumption in male smokers

Psychoeducation (PE) has been widely used in smoking interventions, but its long-term effects are limited. Recent studies have reported that, in some fields, a combination of transcranial direct current stimulation (tDCS) and cognitive training (e.g., working memory tasks) may improve cognitive outcomes; thus, we aimed to investigate whether such a combined intervention has a better effect than a PE intervention for reducing smoking cravings and cigarette consumption. In Exp. 1, 19 male smokers received four types of interventions at one-week intervals. In each session, participants were presented with audio PE (or control) while receiving 2-mA active (or sham) tDCS of the dorsolateral prefrontal cortex (DLPFC). In Exp. 2, 48 male smokers were randomized into four experimental groups (PE + Active, Control + Active, PE + Sham, or Control + Sham). Each participant received one type of five-day intervention (i.e., watching a five-minute PE/Control video twice while receiving 2-mA active/sham tDCS) and was followed up for one week. The results showed (a) an enhancement effect of tDCS on PE’s ability to reduce cigarette consumption; (b) that repeated PE has a cumulative effect on reducing both craving and cigarette consumption during the intervention period; and (c) that, compared with PE alone, PE combined with tDCS is capable of helping participants maintain a low intake of cigarettes over one week. These findings suggest that repeated interventions of PE combined with tDCS may be effective in reducing smoking consumption and that further studies are warranted to confirm its application.

Nicotine Use and Metabotropic Glutamate Receptor 5 in Individuals With Major Depressive and Posttraumatic Stress Disorders

Metabotropic glutamate receptor 5 (mGluR5) dysregulation has been implicated in the pathophysiology of many psychiatric disorders, as well as nicotine use and dependence. We used positron emission tomography with [18F]FPEB to measure mGluR5 availability in vivo in 6 groups: (1) nicotine users (NUs) without other psychiatric comorbidities (n = 23); (2) comparison controls (CCs) without nicotine use or psychiatric comorbidities (n = 38); (3) major depressive disorder subjects with concurrent nicotine use (MDD-NU; n = 19); (4) MDD subjects without concurrent nicotine use (MDD-CC; n = 20); (5) posttraumatic stress disorder subjects with concurrent nicotine use (PTSD-NU; n = 17); and (6) PTSD subjects without concurrent nicotine use (PTSD-CC; n = 16). The goal of the study was to test the hypothesis that mGluR5 availability in key corticolimbic regions of interest (ROIs) is different in NU with versus without comorbid psychiatric disorders (ROI: dorsolateral prefrontal cortex [dlPFC], orbitofrontal cortex [OFC], ventromedial prefrontal cortex [vmPFC], anterior cingulate cortex [ACC], amygdala, hippocampus). We found that NU had 11%–13% lower mGluR5 availability in OFC, vmPFC, dlPFC, and ACC as compared with CC, while PTSD-NU had 9%–11% higher mGluR5 availability in OFC, dlPFC, and ACC compared with PTSD. Furthermore, relationships between mGluR5 availability and psychiatric symptoms varied as a function of psychiatric diagnosis among NUs. NU showed a negative correlation between mGluR5 and smoking cravings and urges (r's = –0.58 to –0.70, p's = 0.011 – 0.047), while PTSD-NU had the reverse relationship (r's = 0.60–0.71, p's = 0.013–0.035 in ACC, vmPFC, and dlPFC). These findings have substantial implications for our understanding of glutamate homeostasis in psychiatric subgroups and for identifying key neural phenotypes among NU. mGluR5 is a potential treatment target for precision medicine in individuals with nicotine use.

Attitudes about Cigarette Smoking, Perceived Consequences of Smoking, and Seeking Assistance with Cessation among Black and White Cigarette Smokers: A Qualitative Study.

Research has identified significant racial differences in cigarette smoking behavior, associated disease risk, likelihood of cessation, and mortality from smoking-related diseases. The current study assessed, via qualitative narrative analysis, racial differences in participants' motivations for smoking, perceived consequences of smoking, and how participants deal with cravings/withdrawal, as well as thoughts and feelings about quitting, seeking assistance with quitting, and the importance of social support in quitting. Semistructured interviews were conducted with 11 Black and 11 White cigarette smokers. Data were analyzed using the Thematic Networks Analysis process, which entailed coding the data and constructing thematic networks by identifying basic and organizing themes. While there were no descriptive racial differences identified in participants' motivation for smoking or perceived consequences of smoking, differences existed between Blacks and Whites in terms of approaches in dealing with smoking cravings and withdrawal, perceived self-efficacy in controlling cravings, preferred methods of learning about and receiving smoking cessation assistance, and overall preference for receiving cessation-related support. Further investigation is needed into racial differences in methods to deal with cigarette cravings and withdrawal, preferences for receiving cessation information, and social support for cessation. This research will further develop our understanding of and ability to address factors underlying racial disparities in smoking behavior and cessation, as well as inform the development of future smoking cessation interventions.

Momentary associations between affect and craving as a function of perceived smoking opportunity in young adults smoking 1–5 cigarettes per day: An ecological momentary assessment study

BackgroundVery light daily smoking (1–5 cigarettes/day) is associated with adverse consequences and is prevalent among young adults. Evidence suggests that perceived smoking opportunity modulates links between affect and craving in adults with heavier smoking patterns (e.g., > 10 cigarettes per day), but there is a lack of similar data in young adults with very light daily smoking patterns. This study addresses this gap by investigating the associations between affect and craving as a function of perceived smoking opportunity under naturalistic conditions. MethodsForty-one young adults aged 18–25 (M=21.03, SD=1.75) who reported smoking 1–5 cigarettes per day (M=3.2, SD=1.2) completed intermittent ratings of momentary affective valence and arousal, smoking craving, and perceived smoking opportunity on smartphones five times per day for seven days. ResultsMultilevel analyses suggested that when participants felt more pleasant or unpleasant, they were likely to report more intense craving. When smoking opportunity was perceived as high, affective arousal was positively associated with craving; this association was not observed when opportunity to smoke was perceived as low. ConclusionsThese findings indicate that higher momentary intensity of affective valence (both negative and positive) is linked to stronger momentary craving in young adults who report very light daily smoking. Anticipating an opportunity to satisfy craving by smoking may strengthen the association between reported affective arousal and craving in this population. These results highlight the potential benefits of coping with craving (e.g., by regulating affect) for those who engage in light tobacco use, especially in environments with high cigarette availability.

Validity of the DSM-5 tobacco use disorder diagnostics in adults with problematic substance use

BackgroundDSM-5 tobacco use disorder (TUD) nosology differs from DSM-IV nicotine dependence (ND) by including craving and DSM-IV abuse criteria, a lower threshold (≥ 2 criteria), and severity levels (mild; moderate; severe). We assessed concurrent and prospective validity of the DSM-5 TUD diagnosis and severity and compared validity with DSM-IV ND diagnosis. MethodsThe sample included U.S. adults with current problematic substance use and past year cigarette smoking (N = 396). Baseline assessment collected information on DSM-IV ND and DSM-5 TUD criteria, smoking-related variables, and psychopathology. Over the following 90 days, electronic daily assessments queried smoking and cigarette craving. Variables expected to be related to TUD were validators: cigarette consumption, cigarette craving scale, Fagerström Test for Nicotine Dependence, and psychiatric disorders. Regression models estimated the association of each validator with DSM-5 TUD and severity levels, and differential association between DSM-5 TUD and DSM-IV ND diagnoses. ResultsDSM-5 TUD and DSM-IV ND were associated with most baseline validators (p-values < 0.05), with significantly stronger associations with DSM-5 TUD for number of days smoked (p = 0.023) and cigarette craving scale (p = 0.007). Baseline DSM-5 TUD and DSM-IV ND predicted smoking and craving on any given day during follow-up, with stronger associations for DSM-5 TUD (association difference [95% CI%]: any smoking, 0.53 [0.27, 0.77]; number of cigarettes smoked, 1.36 [0.89, 1.78]; craving scale, 0.19 [0.09, 0.28]). Validators were associated with TUD severity in a dose-dependent manner. ConclusionDSM-5 TUD diagnostic measures as operationalized here demonstrated concurrent and prospective validity. Inclusion of new criteria, particularly craving, improved validity and clinical relevance.