Polymorphisms in the A118G SNP of the OPRM1 gene produce different experiences of opioids: A human laboratory phenotype-genotype assessment.

Allelic variations in the A118G SNP of the OPRM1 gene change opioid signaling; however, evaluations of how allelic differences may influence opioid effects are lacking. This human laboratory paradigm examined whether the AA versus AG/GG genotypes determined opioid response profiles. Individuals with limited opioid exposure (N = 100) completed a five-day within-subject, double-blind, placebo-controlled, residential study. Participants were admitted (Day 1), received 4 mg hydromorphone (Day 2) and 0 mg, 2 mg and 8 mg hydromorphone in randomized order (Days 3-5) and completed self-reported visual analog scale (VAS) ratings and Likert scales, observed VAS, and physiological responses at baseline and for 6.5 h post-dose. Outcomes were analysed as peak/nadir effects over time as a function of genotype (available for N = 96 individuals; AG/GG = 13.5%, AA = 86.4%). Participants with AG/GG rated low and moderate doses of hydromorphone as significantly more positive (e.g., Good Effects VAS, coasting, drive, friendly, talkative, stimulation) with fewer negative effects (e.g., itchy skin, nausea, sleepiness), and were also observed as being more talkative and energetic relative to persons with AA. Persons with AG/GG were less physiologically reactive as determined by diastolic blood pressure and heart rate, but had more changes in core temperature compared with those with AA. Persons with AA also demonstrated more prototypic agonist effects across doses; persons with AG/GG showed limited response to 2 mg and 4 mg. Data suggest persons with AG/GG genotype experienced more pleasant and fewer unpleasant responses to hydromorphone relative to persons with AA. Future studies should replicate these laboratory findings in clinical populations to support a precision medicine approach to opioid prescribing.

Relating individual differences in the reinforcing value of smoking and dependence severity to nicotine exposure levels in vulnerable populations.

Cigarette smoking is overrepresented in populations with psychiatric conditions and socioeconomic disadvantage. Greater understanding of the role of reinforcement and nicotine dependence in smoking among vulnerable populations may facilitate development of better targeted interventions to reduce smoking. Prior research demonstrated that individual differences in the reinforcing value of smoking and nicotine-dependence severity predicted total nicotine-exposure in vulnerable populations. The present study uses multivariate regression to address two aims: (1) Quantify the degree to which the reinforcing value of smoking, assessed using the Cigarette Purchase Task (CPT), and dependence severity assessed using the Fagerström Test of Nicotine Dependence and Brief Wisconsin Inventory of Smoking Dependence Motives (B-WISDM) each account for individual differences in cotinine-plus-3'-hydroxycotinine (COT+3HC) levels. (2) Explore whether there is overlap in the variance accounted for by the CTP, FTND, and B-WISDM. Participants were 628 adults with co-morbid psychiatric conditions or socioeconomic disadvantage who smoked daily. The CPT, FTND, and B-WISDM models accounted for 23.76%, 32.45%, and 29.61% of the variance in COT+3HC levels, respectively. Adding CPT to the FTND model failed to increase the variance accounted for and adding it to the B-WISDM model did so by only 1.2% demonstrating considerable overlap in the variance in nicotine exposure levels accounted for by these three instruments. These results provide new knowledge on the relationship between individual differences in the reinforcing value of smoking and nicotine-exposure levels and suggest differences in reinforcing value may underpin a considerable portion of the variance in nicotine exposure accounted for by dependence severity.

Abuse liability of cigarettes with very low nicotine content in pregnant cigarette smokers.

The U.S. Food and Drug Administration has proposed reducing the nicotine content of cigarettes to a minimally-addictive level. To our knowledge, this study is the first to examine how pregnant smokers respond to very low nicotine content (VLNC) cigarettes. In Phase 1, participants blindly sampled two VLNC cigarettes (0.4 and 2.4 mg/g of tobacco) and their usual brand (UB) cigarette in separate sessions, then completed a behavioral economic simulation task and measures of subjective effects, craving/withdrawal, and smoking topography. Phase 2 directly compared the relative reinforcing effects of the cigarettes using concurrent choice testing. All possible dose-pair combinations were tested in separate sessions where puffs were earned ad libitum by clicking the code associated with their preferred cigarette 10 times. Phase 3 tested the 0.4 mg/g-UB dose-pair where UB puffs could be earned with a progressively incremented number of clicks (maximum 8400). Ten pregnant smokers in Burlington, VT and Baltimore, MD participated in 2017-2018. Regarding abuse liability, participants chose the 0.4-mg/g dose less than UB (22% vs. 78%) during concurrent choice testing and the 0.4-mg/g dose sustained less demand than the 2.4-mg/g and UB doses on the simulation task. Positive subjective effects were also lower for both VLNC cigarettes vs. UB. Each cigarette reduced nicotine craving/withdrawal and no significant changes indicative of compensatory smoking were noted. Reducing the nicotine content of cigarettes may decrease their abuse liability in pregnant smokers without causing untoward craving/withdrawal or compensatory smoking. Studies of extended exposure to VLNCs in pregnant women are warranted.

Potential Moderating Effects of Sex/Gender on the Acute Relative Reinforcing and Subjective Effects of Reduced Nicotine Content Cigarettes in Vulnerable Populations.

INTRODUCTION: Reports in relatively healthy smokers suggest men are more sensitive than women to the subjective effects of reduced nicotine content cigarettes (RNCCs). We know of no reports examining sex differences in the relative reinforcing effects of RNCCs, an important outcome in assessing smoking's addiction potential. The aim of the present study is to address this gap by examining sex/gender differences on reinforcing effects while examining whether sex differences in subjective effects are discernible in vulnerable populations. METHODS: Secondary analysis of a within-subject, double-blinded experiment examining acute effects of cigarettes varying in nicotine content (0.4, 2.4, 5.2, 15.8 mg/g) among 169 adult smokers with psychiatric conditions or socioeconomic disadvantage. Effects of dose, sex, and their interaction were examined on reinforcing (concurrent-choice and Cigarette Purchase Task [CPT] testing), and subjective effects (Cigarette Evaluation Questionnaire [CEQ] and craving/withdrawal ratings). RESULTS: Reducing nicotine content decreased the relative reinforcing effects of smoking in concurrent-choice and CPT testing (p's < .05) with no significant effects of sex nor dose × sex/gender interactions. Reducing nicotine content decreased CEQ ratings with only a single significant effect of sex (higher Psychological Reward scores among women than men, p = .02) and no significant dose × sex/gender interactions. Results on craving/withdrawal paralleled those on the CEQ. CONCLUSIONS: Reducing nicotine content decreases the addiction potential of smoking independent of sex in populations highly vulnerable to smoking and addiction, with no indication that women are less sensitive to subjective effects of RNCCs or would benefit less from a policy reducing the nicotine content of cigarettes. IMPLICATIONS: A policy reducing the nicotine content of cigarettes has the potential to reduce the addiction potential of smoking across men and women who are especially vulnerable to smoking, addiction, and tobacco-related adverse health impacts.

Non-Opioid Neurotransmitter Systems that Contribute to the Opioid Withdrawal Syndrome: A Review of Preclinical and Human Evidence.

Opioid misuse and abuse is a major international public health issue. Opioid use disorder (OUD) is largely maintained by a desire to suppress aversive opioid withdrawal symptoms. Opioid withdrawal in patients seeking abstinence from illicit or prescribed opioids is often managed by provision of a µ-opioid agonist/partial agonist in combination with concomitant medications. Concomitant medications are administered based on their ability to treat specific symptoms rather than a mechanistic understanding of the opioid withdrawal syndrome; however, their use has not been statistically associated with improved treatment outcomes. Understanding the central and/or peripheral mechanisms that underlie individual withdrawal symptom expression in humans will help promote medication development for opioid withdrawal management. To support focused examination of mechanistically supported concomitant medications, this review summarizes evidence from preclinical (N = 68) and human (N = 30) studies that administered drugs acting on the dopamine, serotonin, cannabinoid, orexin/hypocretin, and glutamate systems and reported outcomes related to opioid withdrawal. These studies provide evidence that each of these systems contribute to opioid withdrawal severity. The Food and Drug Administration has approved medications acting on these respective systems for other indications and research in this area could support the repurposing of these medications to enhance opioid withdrawal treatment. These data support a focused examination of mechanistically informed concomitant medications to help reduce opioid withdrawal severity and enhance the continuum of care available for persons with OUD.

Randomized comparison of two web-based interventions on immediate and 30-day opioid overdose knowledge in three unique risk groups.

BACKGROUND: In response to the opioid overdose epidemic, scalable interventions that instruct at-risk populations how to prevent and respond to overdose scenarios are needed. METHOD: The following groups of at-risk individuals were recruited online: (1) Acute Pain patients with an opioid prescription, (2) Chronic Pain patients with an opioid prescription, and (3) persons without pain who use Illicit Opioids. Participants were tested on their opioid overdose knowledge using the Brief Opioid Overdose Knowledge (BOOK) questionnaire and randomized to one of two web-based interventions that contained 25 educational content slides. One intervention consisted of embedded questions with corrective feedback (Presentation + Mastery, n = 58), the other did not (Presentation, n = 61). Participants completed the BOOK again at the end of the intervention and 30 days later. Overdose risk behaviors were assessed at baseline and 30-days. RESULTS: Relative to baseline, both Presentation and Presentation + Mastery interventions increased total BOOK scores immediately and 30 days later. There was a significant effect of Group on BOOK Knowledge, whereby those with Acute Pain had lower scores across time, regardless of intervention, relative to those with Chronic Pain and Illicit Opioid Use. Compared to baseline, all three groups reported fewer instances of using opioids alone or concurrently with alcohol at the 30-day follow-up. CONCLUSIONS: A web-based intervention increased opioid overdose knowledge and decreased overdose risk behavior immediately and at a one-month follow-up, suggesting that this brief, practical, and scalable program could have utility in several populations who are at-risk of opioid overdose.

Examining effects of unit price on preference for reduced nicotine content cigarettes and smoking rate.

Cigarette preference increases as a function of greater nicotine content, but manipulating cost can shift preference. The aims of the present study are to model whether (1) the behavioral-economic metric unit price (cost/reinforcer magnitude) accounts for preference shifts and (2) whether preference shifts toward reduced nicotine content are associated with smoking reductions. In a multisite study between 2015 and 2016, 169 daily smokers from vulnerable populations completed two concurrent-choice conditions examining preference for smoking normal (15.8 mg/g) and reduced (0.4 mg/g) nicotine content cigarettes. In Condition 1, both products were available at 10 responses/choice. In Condition 2, availability of the 0.4 mg/g dose remained at 10 responses/choice while the 15.8 mg/g dose was available on a progressive-ratio (PR) schedule wherein response cost increased following each choice. Unit prices were calculated by dividing dose by response requirement. Results were analyzed using ANOVA and binomial tests (p < .05). Participants preferred the 15.8 over 0.4 mg/g dose in Condition 1, but shifted preference to the 0.4 mg/g dose in Condition 2 (p < .001) immediately before the point in the PR progression where unit price for 15.8 dose exceeded unit price for the 0.4 dose (p < .001). This shift was associated with a reduction in smoking (p < .001). The unit price of nicotine appears to underpin cigarette product preference and may provide a metric for predicting preference and potentially impacting it through tobacco regulations. These results also demonstrate that reduced compared to normal nicotine content cigarettes sustain lower smoking rates discernible even under acute laboratory conditions and in vulnerable populations.

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.

Comparing Smoking Topography and Subjective Measures of Usual Brand Cigarettes Between Pregnant and Non-Pregnant Smokers.

Introduction: Most pregnant smokers report abruptly reducing their cigarettes per day (CPD) by ~50% after learning of pregnancy and making further smaller reductions over the remainder of their pregnancy. Laboratory and naturalistic studies with non-pregnant smokers have found that these types of reductions often lead to changes in smoking topography (i.e., changes in smoking intensity to maintain a desired blood-nicotine level). If pregnant women smoke more intensely, they may expose themselves and their offspring to similar levels of toxicants despite reporting reductions in CPD. Methods: Pregnant and non-pregnant female smokers (n = 20 and 89, respectively) participated. At the experimental session, after biochemical confirmation of acute abstinence, participants smoked one usual brand cigarette ad lib through a Borgwaldt CReSS Desktop Smoking Topography device. Carbon monoxide (CO) and measures of nicotine withdrawal, craving, and reinforcement derived from smoking were also collected. Results: The two groups did not differ on demographic or smoking characteristics at screening, except nicotine metabolism rate, which as expected, was faster in pregnant smokers. Analyses suggest that none of the smoking topography parameters differed between pregnant and non-pregnant smokers, although pregnant smokers had a significantly smaller CO boost. Both groups reported similar levels of relief of withdrawal and craving after smoking, but other subjective effects suggest that pregnant smokers find smoking less reinforcing than non-pregnant smokers. Conclusions: Pregnant smokers do not smoke cigarettes differently than non-pregnant women, but appear to find smoking comparatively less pleasurable. Implications: This is the first study to assess smoking topography in pregnant women. Pregnant women appear to be at increased risk for smoking cigarettes with more intensity because of (1) their tendency to make significant abrupt reductions in the number of cigarettes they smoke each day after learning of pregnancy and (2) an increase in nicotine metabolism induced by pregnancy. Despite these changes, the present results suggest that pregnant women do not smoke cigarettes more intensely or in a way that causes more toxicant exposure, perhaps due to a reportedly less pleasurable smoking experience.

Physical activity and cannabis cessation.

BACKGROUND AND OBJECTIVES: Based on recent empirical and theoretical work suggesting that physical activity (PA) activates many of the same physiological systems as cannabis, the present study sought to investigate the impact of PA level (ie, low [including none] vs. moderate/high) on a cannabis cessation attempt during the first 7 days post-quit. METHODS: The present study was a 2 time-point prospective study of 84 cannabis dependent military veterans (3 female) who responded to study flyers, within a Veterans Affairs Medical Center, seeking individuals interested in engaging in a self-guided cessation attempt. All study measures were self-report. RESULTS: Though no baseline differences between those with low and those with moderate/high levels of physical activity were observed, results revealed that participants who reported low levels of physical activity, versus moderate/high levels, were significantly more likely to report a cannabis lapse during the week following a quit attempt, particularly within the first 4 days of the cessation period. Further, individuals with low levels of PA were also more likely to report greater mean cannabis use during the first 4 days of the cessation period. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: Findings suggest that early interventions aimed at increasing physical activity may be useful among individuals with cannabis dependence who are engaged in a cessation attempt.

Opioid craving does not incubate over time in inpatient or outpatient treatment studies: Is the preclinical incubation of craving model lost in translation?

Within addiction science, incubation of craving is an operational label used to describe time-dependent increases in drug seeking during periods of drug deprivation. The purpose of this systematic review was to describe the preclinical literature on incubation of craving and the clinical literature on craving measured over extended periods of abstinence to document this translational homology and factors impacting correspondence. Across the 44 preclinical studies that met inclusion criteria, 31 reported evidence of greater lever pressing, nose pokes, spout licks, or time spent in drug-paired compartments (i.e., drug seeking) relative to neutral compartments after longer periods of abstinence relative to shorter periods of abstinence, labelled as "incubation of craving." In contrast, no clinical studies (n = 20) identified an increase in opioid craving during longer abstinence periods. The lack of clinical evidence for increases in craving in clinical populations weakens the translational utility of operationalizing the time-dependent increase in drug-seeking behavior observed in preclinical models as models of incubation of "craving".

Virtual focus groups among individuals with use disorders: assessing feasibility and acceptability in an underserved clinical population.

Objective: There are substantial barriers to conducting research among individuals with stigmatized and complicated health conditions like substance use disorders. These barriers slow progress when developing, refining, and assessing interventions to better treat underserved populations. Virtual focus groups are an innovative method for collecting data from individuals via a discreet and accessible platform which can inform novel as well as existing treatment approaches. This article reports on the feasibility and acceptability of virtual focus groups as a mechanism to recruit and engage geographically and demographically diverse samples of participants with substance use disorders that are otherwise logistically difficult to assess. Method: Participants were assessed for eligibility for a virtual focus group study based on demographic features, drug use history, and psychiatric history via a remote, interview-based screening. Focus groups were completed anonymously without video or name-sharing. Discussion contributions, quantified with number of times speaking and total number of words spoken, were compared across gender, and treatment status. Participants provided quantitative and qualitative feedback on the focus group experience in a follow-up survey. Results: Focus groups (N=26) based in geographical areas throughout the United States were conducted with 88 individuals with opioid use disorder or stimulant use disorder. Discussion contributions were comparable between genders and among individuals in treatment versus those seeking treatment. A follow-up survey (n=50, 57% of focus group participants) reflected high levels of enjoyment, comfort, and honesty during focus group discussions. Discussion: Findings suggest virtual focus groups can be an effective and efficient tool for substance use research.

The subjective value of social context in people who use cannabis.

Disordered cannabis use is linked to social problems, which could be explained by a subjective devaluation of nondrug social contexts and/or an overvaluation of cannabis-paired options relative to nondrug alternatives. To examine these hypotheses, measures to assess the subjective value of social- and/or cannabis-paired contexts were collected in people who use cannabis (n = 85) and controls (n = 98) using crowdsourcing methods. Measures included a cued concurrent choice task that presented two images (cannabis, social, social cannabis, and neutral images) paired with monetary options, hypothetical purchase tasks that included access to social parties with and without a cannabis "open bar," and the Social Anhedonia Scale (SAS). Little evidence was found to suggest that the cannabis group undervalued social contexts. People who used cannabis demonstrated a preference for social- versus neutral-cued options, and no preference for cannabis- versus social cannabis-cued options on the choice task. In addition, social party demand and SAS scores did not differ between groups. In contrast, we observed evidence for an overvaluation of cannabis context in people who use cannabis, including preference for social cannabis- versus social-cued options, and more disadvantageous choices for cannabis-cued options on the choice task, as well as more intense and inelastic demand for the social cannabis party compared to the social party. These results suggest that social problems associated with cannabis use could be at least partially explained by an overvaluation of cannabis-paired options, rather than devaluation of nondrug social-paired options, in the value calculations underlying drug use decisions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Changes in weight among individuals with psychiatric conditions or socioeconomic disadvantage assigned to smoke very low nicotine content cigarettes.

Nicotine abstinence leads to weight gain, which could be an unintended consequence of a nicotine reduction policy. This secondary analysis used weekly assessments of weight and ratings of "increased appetite/hunger/weight gain" collected in three 12-week, randomized controlled trials evaluating the effects of cigarettes differing in nicotine dose (15.8, 2.4, or 0.4 mg/g) among individuals with affective disorders, opioid use disorder (OUD), and socioeconomically disadvantaged women. Linear mixed models tested differences by dose and time. Analyses first collapsed across populations and then separated out individuals with OUD because biomarkers suggested they used substantially more noncombusted nicotine. Across populations, weight increased significantly over time, averaging 1.03 kg (p < .001), but did not vary by dose nor was there any interaction of dose/time. "Increased appetite/hunger/weight gain" ratings increased significantly as a function of dose, with differences between low and high doses (1.95 and 1.73, respectively, p = .01), but not by time nor any interaction. In the combined group of individuals with affective disorders and socioeconomically disadvantaged women, weight and "increased appetite/hunger/weight gain" ratings increased significantly by dose, with differences between low and high doses (1.43 vs. 0.73 kg, p = .003 and 2.00 vs. 1.76, p = .02, respectively). Among individuals with OUD, there were no significant effects of any kind on either outcome. Individuals with affective disorders and socioeconomically disadvantaged women gained weight and reported more subjective appetite/weight gain when given 0.4, but not 2.4 mg/g cigarettes, despite comparable decreases in nicotine exposure. However, neither change was clinically significant, suggesting minimal short-term adverse consequences of a nicotine reduction policy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Within subject, double blind, examination of opioid sensitivity in participant-reported, observed, physiologic, and analgesic outcomes.

Background: Inter-individual differences in opioid sensitivity may underlie different opioid risk profiles but have often been researched in persons who have current or past opioid use disorder or physical dependence. This study examined how opioid sensitivity manifests across various assessments of opioid effects in a primarily opioid-naïve population. Procedures: Data were harmonized from two within-subject, double-blind trials wherein healthy participants (N = 123) received placebo and 4 mg oral hydromorphone. Demographics, self-report ratings, observer ratings, physiological, and cold pressor measures were collected. Participants were categorized as being responsive or nonresponsive to the opioid dose tested and compared using mixed-models, Pearson product correlations, and paired t-tests. Findings: Participants were 49.6% female, mean 33.0 (SD=9.3) years old, and 44.7% Black/African American and 41.5% White, with 89.4% reporting no prior exposure to opioids. Within-subject sensitivity to opioids varied depending on the measure. One in five participants did not respond subjectively to the 4 mg hydromorphone dose based on their "Drug Effects" rating. Persons who were responsive showed more evidence of drug-dependent effects than did persons who were not responsive on ratings of Bad Effects (p= .03), feeling High (p= .01), Nausea (p= .03), pupil diameter (p< 0.01), and on the circular lights task (p< 0.001). Conclusions: This study provides initial evidence that the experience of opioids may be domain specific. Data suggest potentially clinically meaningful differences exist regarding opioid response patterns, evident following one dose among opioid inexperienced individuals.

A double-blind, randomized, placebo-controlled, pilot clinical trial examining buspirone as an adjunctive medication during buprenorphine-assisted supervised opioid withdrawal.

Successful management of opioid withdrawal improves long-term treatment outcomes and reduces opioid use-related morbidity and mortality. Mechanistically supported pharmacotherapeutic approaches are needed to effectively manage acute and protracted opioid withdrawal. Buspirone is a D2 antagonist and 5-HT1a agonist that may decrease opioid withdrawal. Individuals (n = 15) admitted to a residential treatment center for opioid use disorder (OUD) were enrolled into a double-blind randomized clinical trial to assess the efficacy and acceptability of buspirone (45 mg/day) as an adjunctive medication to buprenorphine-assisted, supervised opioid withdrawal. Participants completed daily questionnaires which consisted of the Subjective Opiate Withdrawal Scale (SOWS) and a consensus sleep diary, which assessed total sleep time, time to sleep onset, and sleep quality. Total SOWS scores, individual opioid withdrawal symptoms and sleep outcomes were assessed between treatment groups (Placebo and Buspirone) and over time in a repeated measures linear mixed model. Total SOWS scores significantly decreased across study phases for both groups but decreased to a greater extent among individuals assigned to buspirone during both the first and second week of stable buspirone. Greater decreases in withdrawal were observed during Week 2 of stable buspirone relative to Week 1 of stable buspirone. Participants also reported significant increases in sleep duration and significant decreases in latency to sleep onset. This study provides further support that buspirone can help mitigate opioid withdrawal during a supervised opioid taper. Buspirone may confer unique benefits during protracted withdrawal periods. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Can initial experiences with drugs predict future drug abuse risks?

Initial experiences with drugs may influence an individual's motivations for continued use. This study evaluated the relationship between subjective effects elicited by an individual's first use of alcohol or cannabis, Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) alcohol use disorder (AUD) or cannabis use disorder (CUD) severity, and behavioral economic demand for alcohol or cannabis. Self-reports of initial subjective effects associated with drugs were analyzed for N = 463 participants whose first substance use was either alcohol or cannabis. The likelihood that a particular subjective effect at the time of first use was associated with current AUD/CUD was assessed using ordinal logistic regression with subjective effects as predictors of DSM-5 severity. Behavioral economic demand was assessed using a hypothetical purchase task in which participants indicated their hypothetical consumption of alcohol or cannabis as a function of price. Significant associations were observed for initial subjective effects elicited by alcohol or cannabis and increased DSM-5 severity: (alcohol) relief (OR = 2.52 [95% CI 1.51-4.25], p = .0005) and (cannabis) energetic (OR = 2.31 [95% CI 3.27-55.5], p = .0004). The mean (± SEM) Pmax value for the alcohol subgroup endorsing relief ($96.22 ± $26.48) was significantly greater than the Pmax value for the alcohol subgroup not endorsing relief ($33.81 ± $12.93), t(237) = 2.276, p = .0237. These results suggest that the initial subjective effects associated with a given substance may predict the development and/or severity of substance misuse and substance use disorders (SUDs). These findings are consistent with anecdotal reports that persons with SUD feel energized by the use of substances whereas persons without SUD do not report experiencing such subjective effects upon first use. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Operational definition of precipitated opioid withdrawal.

Background: Opioid withdrawal can be expressed as both a spontaneous and precipitated syndrome. Although spontaneous withdrawal is well-characterized, there is no operational definition of precipitated opioid withdrawal. Methods: People (N = 106) with opioid use disorder maintained on morphine received 0.4 mg intramuscular naloxone and completed self-report (Subjective Opiate Withdrawal Scale, SOWS), visual analog scale (VAS), Bad Effects and Sick, and observer ratings (Clinical Opiate Withdrawal Scale, COWS). Time to peak severity and minimal clinically important difference (MCID) in withdrawal severity were calculated. Principal component analysis (PCA) during peak severity were conducted and analyzed with repeated measures analyses of variance (ANOVA). Results: Within 60 min, 89% of people reported peak SOWS ratings and 90% of people had peak COWS scores as made by raters. Self-reported signs of eyes tearing, yawning, nose running, perspiring, hot flashes, and observed changes in pupil diameter and rhinorrhea/lacrimation were uniquely associated with precipitated withdrawal. VAS ratings of Bad Effect and Sick served as statistically significant severity categories (0, 1-40, 41-80, and 81-100) for MCID evaluations and revealed participants' identification with an increase of 10 [SOWS; 15% maximum percent effect (MPE)] and 6 (COWS; 12% MPE) points as meaningful shifts in withdrawal severity indicative of precipitated withdrawal. Conclusion: Data suggested that a change of 10 (15% MPE) and 6 (12% MPE) points on the SOWS and COWS, respectively, that occurred within 60 min of antagonist administration was identified by participants as a clinically meaningful increase in symptom severity. These data provide a method to begin examining precipitated opioid withdrawal.

The impact of opioid-stimulant co-use on tonic and cue-induced craving.

The twin opioid-stimulant epidemics have led to increased overdose deaths and present unique challenges for individuals entering treatment with opioid-stimulant polysubstance use. This study examined tonic and cue-induced craving as a primary outcome among persons in substance use treatment who reported primary substances of opioids, methamphetamine, or cocaine. The sample consisted of 1974 individuals in 55 residential substance-use treatment centers in the United States in 2021. Weekly surveys were delivered via a third-party outcomes tracking system, including measures of tonic and cue-induced craving. Initial comparisons on tonic and cue-induced craving were made among those who primarily used opioids, cocaine, or methamphetamine. Further, the effect of opioid/stimulant polysubstance use on tonic and cue-induced craving was evaluated using marginal effect regression models. Primary methamphetamine use was associated with decreased tonic craving compared to primary opioid use (ß = -5.63, p < 0.001) and primary cocaine use was also associate with decreased tonic craving compared to primary opioid use (ß = -6.14, p < 0.001). Primary cocaine use was also associated with lower cue-induced cravings compared to primary opioid use (ß = -0.53, p = 0.037). Opioid-methamphetamine polysubstance use was associated with higher tonic craving (ß = 3.81, p = <0.001) and higher cue-induced craving (ß = 1.55, p = 0.001); however, this was not the case for opioid-cocaine polysubstance use. The results of this study indicate that individuals who primarily use opioids and have secondary methamphetamine use experience higher cue-induced and tonic-induced craving, suggesting that these individuals may benefit from additional interventions that target craving and mitigate relapse risk and other negative sequelae.

Within-subject, double-blind, randomized, placebo-controlled evaluation of combining the cannabinoid dronabinol and the opioid hydromorphone in adults with chronic pain.

The potential synergistic effects of combining cannabinoids and opioids for analgesia has received considerable attention. No studies to date have evaluated this combination in patients with chronic pain. The present study aimed to evaluate the combined analgesic and drug effects of oral opioid (hydromorphone) and delta-9-tetrahydrocannabinol (dronabinol), as well as their effects on physical and cognitive functioning, and human abuse potential (HAP) outcomes among individuals with knee osteoarthritis (KOA). This was a within-subject, double-blind, randomized, placebo-controlled study. Participants (N = 37; 65% women; mean age = 62) diagnosed with knee osteoarthritis of ≥3/10 average pain intensity were included. Participants received (1) placebo-placebo, (2) hydromorphone (4 mg)-placebo; (3) dronabinol (10 mg)-placebo, and (4) hydromorphone (4 mg)-dronabinol (10 mg). Clinical and experimentally-induced pain, physical and cognitive function, subjective drug effects, HAP, adverse events, and pharmacokinetics were evaluated. No significant analgesic effects were observed for clinical pain severity or physical functioning across all drug conditions. Little enhancement of hydromorphone analgesia by dronabinol was observed on evoked pain indices. While subjective drug effects and some HAP ratings were increased in the combined drug condition, these were not significantly increased over the dronabinol alone condition. No serious adverse events were reported; hydromorphone produced more mild adverse events than placebo, but hydromorphone + dronabinol produced more moderate adverse events than both placebo and hydromorphone alone. Only hydromorphone impaired cognitive performance. Consistent with laboratory studies on healthy adults, the present study shows minimal benefit of combining dronabinol (10 mg) and hydromorphone (4 mg) for analgesia and improving physical functioning in adults with KOA.