Leveraging meta-regression to test if medication effects on cue-induced craving are associated with clinical efficacy

RATIONALE

The alcohol cue exposure paradigm is a common method for evaluating new treatments for alcohol use disorder (AUD); however, it is unclear if medication-related reductions in cue-induced craving in the human laboratory can predict the clinical success of those medications in reducing alcohol consumption during clinical trials.

OBJECTIVES

To use a novel meta-analytic approach to test whether medication effect sizes on cue-induced alcohol craving are associated with clinical efficacy in clinical trials.

METHOD

We searched the literature for medications tested for AUD treatment using both the alcohol cue-reactivity paradigm and randomized clinical trials (RCTs). For alcohol cue-reactivity studies, we computed medication effect sizes for cue-induced alcohol craving (k = 36 studies, 15 medications). For RCTs, we calculated medication effect sizes for heavy drinking and abstinence (k = 139 studies, 19 medications). Using medication as the unit of analysis, we applied the Williamson-York bivariate weighted least squares estimation to account for errors in both independent and dependent variables. We also conducted leave-one-out cross validation simulations to examine the predictive utility of cue-craving medication effect sizes on RCT heavy drinking and abstinence endpoints.

RESULTS

There was no significant relationship between medication effects on cue-induced alcohol craving in the human laboratory and medication effects on heavy drinking ( β ^ = 0.253, SE = 0.189, p = 0.090) and abstinence ( β ^ = 0.829, SE = 0.747, p = 0.133) in RCTs.

CONCLUSIONS

The preliminary results of the current study challenge the assumption that alcohol cue-reactivity alone can be used as an early efficacy indicator for AUD pharmacotherapy development. These findings suggest that a wider range of early efficacy indicators and experimental paradigms be considered for Phase II testing of novel compounds.

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 (β = -5.63, p < 0.001) and primary cocaine use was also associate with decreased tonic craving compared to primary opioid use (β = -6.14, p < 0.001). Primary cocaine use was also associated with lower cue-induced cravings compared to primary opioid use (β = -0.53, p = 0.037). Opioid-methamphetamine polysubstance use was associated with higher tonic craving (β = 3.81, p = <0.001) and higher cue-induced craving (β = 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.

The transcranial direct current stimulation over prefrontal cortex combined with the cognitive training reduced the cue-induced craving in female individuals with methamphetamine use disorder: A randomized controlled trial

BACKGROUND

Craving and cognitive deficits are potential treatment targets for methamphetamine use disorder (MUD). Previous studies implied that transcranial direct current stimulation (tDCS) and cognitive training respectively improve these symptoms, but the combined effect is unknown. In this study, we investigated the combined effects of tDCS over dorsolateral prefrontal cortex (DLPFC) and computerized cognitive addiction therapy (CCAT) on cue-induced craving and cognitive functions among female individuals with MUD.

METHODS

Seventy-five patients with MUD were randomly assigned to three groups: CCAT + tDCS group, CCAT + sham tDCS group and the control group. The former two groups received 20 sessions of cognitive training combined 1.5 mA active/sham tDCS over DLPFC (20min/session, 5times/week), while the control group received usual care which includes routine medical care, health education, physical exercises and psychological support related to relapse prevention. The cue-induced craving and cognitive functions were tested at the baseline, the end of 2nd week and 4th week.

RESULTS

The CCAT + tDCS group showed a significant reduction in cue-induced craving after 4-week intervention. Moreover, the craving score of the real CCAT + tDCS group was significantly lower than that of the CCAT + sham tDCS group and that of the control group at the end of 4th week. A significant improvement in accuracy of TWOB task was only observed in the CCAT + tDCS group at the end of 4th week when compared to baseline. Unexpectedly, participants who received CCAT plus active or sham tDCS did not change their discounting, whereas those in the control group performed more impulsively over time.

CONCLUSIONS

The study found that the intervention of tDCS over DLPFC combined with CCAT may have potential benefit in improving treatment outcome in patients with MUD. More research is needed to explore the underlying mechanism.

Detection of patients with methamphetamine dependence with cue-elicited heart rate variability in a virtual social environment

In the present study, we developed a methamphetamine (METH)-related virtual social environment to elicit subjective craving and physiological reactivity. Sixty-one male patients who were abstinent from METH use and 45 age-matched healthy males (i.e., normal controls) were recruited. The physiological electrocardiogram (ECG) signals were recorded before (resting-state condition) and during viewing of a METH-cue video in the virtual environment (cue-induced condition). The cue-induced subjective craving was measured with a visual analogue scale (VAS) for patients with METH dependence. The results indicated that the cue-induced condition elicited significant differences in heart rate variability (HRV) between patients with METH dependence and normal controls. The changes of HRV indexes on time domain and non-linear domain from the resting-state condition to the cue-induced condition were positively correlated with the score on VAS of METH craving. Using a supervised machine learning algorithm with the features extracted from HRV changes, our results showed that the discriminant model provided a high predictive power for distinguishing patients with METH dependence from normal controls. Our findings support that immersing subjects with METH dependence in a METH-related virtual social environment can successfully induce physiological reactivity, and cue-induced physiological signal changes may have a potential implication in clinical practice.

Can attitudes about smoking impact cigarette cravings?

Cigarette cravings, especially those in response to environmental stressors and other smoking-related triggers (e.g., passing by a favorite smoking spot), are important contributors to smoking behavior and relapse. Previous studies have demonstrated significant individual differences in such cravings. This study explores the possibility that attitudes about smoking can influence the experience of cigarette craving. Consistent with classical theories of the links between cognition and motivation, we predicted that smokers who exhibit more favorable attitudes towards smoking would have greater cravings. Daily smokers (n=103, mean age=41.8years, 33% female) were instructed to imagine smoking, stress, and neutral scenarios. Cravings were measured prior to and after each exposure. Participants also completed an abridged version of the Smoking Consequence Questionnaire (SCQ) that had them rate the: 1) desirability and 2) likelihood, for eighteen separate negative smoking consequences (e.g., "The more I smoke, the more I risk my health", "People will think less of me if they see me smoking"). Findings revealed that favorable attitudes about the consequences of smoking, as measured by the SCQ-desirability index, significantly predicted cigarette cravings. Findings suggest that individual attitudes toward smoking may play an important role in better understanding cigarette cravings, which may ultimately help identify targets for more efficient and effective cognitive/attitude-based interventions for smoking cessation.

Psychometric evaluation of a Swedish version of the Shortened Desires for Alcohol Questionnaire (Shortened-DAQ)

INTRODUCTION

Craving is a clinically important feature of alcohol use disorders (AUD), representing a diagnostic criterion as well as a target for treatment. The Desire for Alcohol Questionnaire (DAQ) is a widely used scale to measure craving. The aim of the current study was to evaluate the psychometric properties of a Swedish version of the Shortened-DAQ.

METHOD

The English DAQ was translated into Swedish and back translated to English. Individuals with a diagnosis of AUD (n=118) participated in a laboratory experiment comprising presentation of alcohol and non-alcohol cues, as well as consumption of an alcoholic drink, with the aim of exploring changes in the craving responses following pharmacological treatment for AUD. Subjective craving across the experimental conditions was recorded using Shortened-DAQ and a Visual Analogue Scale (VAS). The psychometric analysis of the Shortened-DAQ investigated some important aspects of reliability, validity and the factor solution using principal components analysis.

RESULTS

Cronbach's alphas were above 0.8 across all sessions, the test-retest correlations were statistically significant. In the alcohol cue session the Shortened-DAQ total score was significantly greater compared to the non-alcohol cue session, and correlated significantly with the VAS craving item across all sessions. The principal component analysis resulted in two significant factors comprised of (1) Alcohol desire and reinforcement and (2) Ability to control drinking. No difference in psychometric properties between treatment and placebo groups were found.

CONCLUSION

In future clinical studies on alcohol craving responses in Swedish patients with AUD, we suggest the use of the Swedish Shortened-DAQ, due to its comparably swift administration and overall acceptable psychometric properties.

Cue-induced craving for Internet among Internet addicts

Intense craving is a core feature of addictive disorder, and cue-induced craving is believed to be a key factor in the maintenance and relapse of addictive behaviors. With the rapid development of the Internet, Internet addiction has become a widespread behavioral problem accompanied by many negative effects. This study used the cue-reactivity paradigm to examine cue-induced craving for the Internet among Internet addicts and non-addicts. Participants were exposed to Internet-related words, and asked to report their craving for the Internet. Results indicated that Internet-related words aroused cue-induced craving for the Internet among both Internet addicts and non-addicts; however, the craving was more intense among Internet addicts. These results suggest that craving may not be a unipolar, all or none state found only in addicts, but may also be present among non-addicts. They indicate that Internet-related words may be able to induce craving for the Internet, and that Internet addiction and other addictions may share similar underlying mechanisms. This finding has important implications for designing interventions for Internet addiction.

Assessing craving and its relationship to subsequent prescription opioid use among treatment-seeking prescription opioid dependent patients

BACKGROUND

Craving is viewed as a core feature of substance use disorders and has been shown to predict future drug use, particularly over the short term. Accordingly, craving is often assessed in treatment settings as a marker of risk for subsequent drug use. The identification of the briefest measure that maintains predictive validity is of particular value for both clinical and research settings to minimize assessment burden while maintaining utility for the prediction of use.

METHODS

Data from a multi-site clinical trial of treatment for prescription opioid dependence were examined to evaluate whether a brief, 3-item craving scale administered each week predicted urine-confirmed self report of prescription opioid use in the subsequent week. Logistic regression models examining the association between craving and presence or absence of opioid use in the following week were conducted, controlling for opioid use in the previous week, treatment condition, and lifetime history of heroin use.

RESULTS

Greater craving was associated with a higher odds of prescription opioid use in the following week. For each one-unit increase on this 10-point scale, the odds of using opioids in the subsequent week was 17% higher. In addition to an item assessing urges, items assessing cue-induced craving and perceived likelihood of relapse in an environment where drugs were previously used contributed uniquely to this association.

CONCLUSIONS

A brief measure of prescription opioid craving predicted prescription opioid use among individuals in treatment. This measure offers an efficient strategy to inform the assessment of risk for use in this population.

Visual cortex activation to drug cues: a meta-analysis of functional neuroimaging papers in addiction and substance abuse literature

BACKGROUND

Although the visual cortex does not typically receive much attention in addiction literature, neuroimaging studies often report significant activity in visual areas when drug users are exposed to drug cues. The purpose of this meta-analysis was to investigate the frequency with which occipital cortex activity is observed during drug cue exposure and to determine its spatial distribution.

METHODS

A comprehensive literature search was performed of human functional neuroimaging studies of drug cue-reactivity. Fifty-five studies were used to determine the frequency with which clusters of significant visual cortex activity during visual drug cues versus non-drug cues were reported. The spatial distribution of visual cortex activations was determined via activation likelihood estimation (ALE; FDR corrected, p<0.01) in a subset of these studies (n=24).

RESULTS

Eighty-six percent of studies that reported fMRI results for drug versus neutral visual cues within a substance-dependent group showed significant drug-elicited activity in the visual cortex. ALE revealed clusters in the left secondary visual cortex (BA 19) and clusters in the primary visual cortex (BA 17) that were consistently activated by drug cues.

CONCLUSIONS

These data demonstrate that the visual cortex, often overlooked in our discussions of the neural circuitry of addiction, consistently discriminates drug cues from neutral cues in substance dependent populations. While it remains unclear whether drug cue-elicited activation in occipital cortex is related to the rewarding properties of the drug and/or attentional mechanisms, these data support further exploration.