Biomarkers of Relapse in Cocaine Use Disorder: A Narrative Review

COT-TT vaccine attenuates cocaine-seeking and cocaine-conditioned place preference in rats

Vaccination active, promising alternative immunological strategy to treat of CUD. Various models of cocaine vaccines have been evaluated in animals and humans with relative success. In this sense, it is necessary to improve or optimize the cocaine vaccines already evaluated. Our laboratory previously reported the efficacy of the tetanus toxoid-conjugated morphine vaccine (M6-TT). The M6-TT vaccine can generate high titers of antibodies and reduce heroin-induced behavioral effects in rodents. So, it would be plausible to assume that if we modify the M6-TT vaccine by changing the hapten and maintaining the rest of the structural elements of the vaccine, we will maintain the properties of the M6-TT vaccine (high antibody titers). The objective of this study was to determine whether the antibodies generated by a tetanus toxoid-conjugated cocaine vaccine (COC-TT) can recognize and capture cocaine and decrease the cocaine-induced reinforcing effects. Male Wistar rats were immunized with the COC-TT. A solid-phase antibody-capture ELISA was used to monitor antibody titer responses after each booster dose in vaccinated animals. The study used cocaine self-administration and place-preference testing to evaluate the cocaine-reinforcing effects. The COC-TT vaccine could generate high levels of anti-cocaine antibodies. The antibodies reduced the cocaine self-administration and cocaine place preference. In addition, they decreased the cocaine-induced Fos protein expression. These findings suggest that the COC-TT vaccine generates a robust immunogenic response capable of reducing the reinforcing effects of cocaine, which supports its possible future use in clinical trials in patients with CUD.

Predictors of abstinence maintenance after cocaine inpatient detoxification: A prospective study

BACKGROUND AND OBJECTIVES

Cocaine is a highly addictive substance, and with no approved medication for cocaine use disorder (CUD), leading to a heavy burden. Despite validated psychosocial treatments, relapse rates after detoxification are very high in CUD. Few consistent factors can predict abstinence after detoxification. Our study, therefore, aimed at identifying factors predicting abstinence among CUD patients after inpatient detoxification.

METHODS

Eighty-one CUD inpatients were included during detoxification and characterized for clinical and sociodemographic data at baseline and at a follow-up of 3 months after discharge, including a standard measure of their abstinence duration from cocaine. We performed Cox univariate analyzes to determine the factors associated with abstinence maintenance, followed by a multivariate Cox regression to identify independent predictors.

RESULTS

Abstinence maintenance was shorter in patients injecting cocaine (hazard ratio [HR] = 5.16, 95% confidence interval [CI]: 2.01-13.27, p < .001) and using cocaine heavily in the month before inclusion (HR = 1.03, 95% CI: 1.00-1.06, p = .046). Conversely, abstinence maintenance was longer in patients with longer inpatient detoxification stays (HR = 0.96, 95% CI: 0.94-0.99, p = .015) and prescribed with selective serotonin reuptake inhibitors (SSRIs) (HR = 0.30, 95% CI: 0.16-0.56, p < .001).

DISCUSSION AND CONCLUSIONS

Patients with severe CUD may require longer inpatient stays to achieve abstinence. Regarding SSRI prescription, more specific studies are needed to provide stronger recommendations about their use in clinical practice.

SCIENTIFIC SIGNIFICANCE

Our findings suggest several modifiable factors to improve inpatient treatment response in CUD. As there are no specific recommendations about the optimal duration of inpatient stay, our results could pave the way for evidence-based guidelines.

Structural and functional pathology in cocaine use disorder with polysubstance use: A multimodal fusion approach structural-functional pathology in cocaine use disorder

Cocaine use disorder (CUD) is described as a compulsive urge to seek and consume cocaine despite the inimical consequences. MRI studies from different modalities have shown that CUD patients exhibit structural and/or functional connectivity pathology among several brain regions. Nevertheless, both connectivities are commonly studied and analyzed separately, which may potentially obscure its relationship between them, and with the clinical pathology. Here, we compare structural and functional brain networks in CUD patients and healthy controls (HC) using multimodal fusion. The sample consisted of 63 (8 females) CUD patients and 42 (9 females) healthy controls (HC), recruited as part of the SUDMEX CONN database. For this, we computed a battery of graph-based measures from multi-shell diffusion-weighted imaging and resting state fc-fMRI to quantify local and global connectivity. Then we used multimodal canonical component analysis plus joint independent component analysis (mCCA+jICA) to compare between techniques and evaluate group differences and its association with clinical alteration. Unimodal results showed a striatal decrease in the participation coefficient but applied supervised data fusion revealed other regions with cocaine-related alterations in joint functional communication. When performing multimodal fusion analysis, we observed a higher centrality of the interrelationship and a lower participation coefficient in patients with CUD. In contrast to the unimodal approach, the multimodal fusion method was able to reveal latent information about brain regions involved in impairment due to cocaine abuse. The present results could help in understanding the pathology of CUD to develop better pre-treatment/post-treatment intervention designs.

Prelimbic cortex and nucleus accumbens core resting state signaling dynamics as a biomarker for cocaine seeking behaviors

Substance use disorders (SUDs) are characterized by maladaptive signaling in the prefrontal cortex and associated regions, however precisely how these drug-induced abnormalities may be linked to drug seeking/taking behaviors is not well understood. Here, in vivo local field potential (LFP) electrophysiology was used in rats to examine the relationship between overall spontaneous (resting state) activity within the prelimbic cortex (PrL) and nucleus accumbens (NAc) core, and their functional connectivity, to cocaine taking and seeking behaviors. Adult, male Sprague-Dawley rats were trained to self-administer either intravenous cocaine (0.33 mg/inf) or water reinforcement during 6-hour daily sessions over 2 weeks; extinction sessions were completed immediately after self-administration training and following 30 days experimenter-imposed abstinence. Rest LFP recordings were completed during 3 recording periods (15 min each in a chamber different from the self-administration context) conducted (1) prior to self-administration training (rest LFP 1) (2) immediately after 2 weeks of self-administration training (rest LFP 2) and (3) following 1 month abstinence (rest LFP 3). Our findings show that resting state LFP power in the PrL recorded prior to training (Rest LFP 1) was positively correlated with total cocaine intake and escalation of cocaine seeking at the beta frequency range. Immediately after self-administration training (Rest LFP 2) power in the NAc core at gamma frequency was negatively correlated with incubation of cocaine craving. For rats trained to self-administer water, no significant correlations were observed. Together, these findings show that resting state LFP at specific timepoints in the addiction cycle can serve as unique predictors (biomarkers) of cocaine use disorders.

Polysubstance addiction patterns among 7,989 individuals with cocaine use disorder

To characterize polysubstance addiction (PSA) patterns of cocaine use disorder (CoUD), we performed a latent class analysis (LCA) in 7,989 participants with a lifetime DSM-5 diagnosis of CoUD. This analysis identified three PSA subgroups among CoUD participants (i.e., low, 17%; intermediate, 38%; high, 45%). While these subgroups varied by age, sex, and racial-ethnic distribution (p < 0.001), there was no difference with respect to education or income (p > 0.05). After accounting for sex, age, and race-ethnicity, the CoUD subgroup with high PSA had higher odds of antisocial personality disorder (OR = 21.96 vs. 6.39, difference-p = 8.08✕10-6), agoraphobia (OR = 4.58 vs. 2.05, difference-p = 7.04✕10-4), mixed bipolar episode (OR = 10.36 vs. 2.61, difference-p = 7.04✕10-4), posttraumatic stress disorder (OR = 11.54 vs. 5.86, difference-p = 2.67✕10-4), antidepressant medication use (OR = 13.49 vs. 8.02, difference-p = 1.42✕10-4), and sexually transmitted diseases (OR = 5.92 vs. 3.38, difference-p = 1.81✕10-5) than the low-PSA CoUD subgroup. These findings underscore the importance of modeling PSA severity and comorbidities when examining the clinical, molecular, and neuroimaging correlates of CoUD.

Neural basis of the attention bias during addiction stroop task in methamphetamine-dependent patients with and without a history of psychosis: an ERP study

Background

Attentional bias plays an important role in sustaining various types of drug addiction. No prior studies examined methamphetamine (MA)-associated psychosis (MAP) relationships between ERP time course and performance on an addiction Stroop task in MA abusers. The aim of the present study was to determine whether MA abusers with (MAP+) or without (MAP-) psychosis exhibit alterations of the ERP during the addiction Stroop task.

Methods

Thirty-one healthy controls (CTRL), 14 MAP-, and 24 MAP+ participants were recruited and completed the addiction Stroop task during EEG recording using 32 electrodes. Group variations were compared on measures of behavioral task performance and event-related potentials (ERP) of performance monitoring (N200, P300, N450). The Barratt impulsiveness scores were analyzed to investigate correlations with ERP changes.

Results

MA-related word stimulus elicited a more negative N200 amplitude over left-anterior electrodes in MAP- abusers; furthermore, a positive association between the N200 amplitude and Barratt attentional scores and non-planning scores was observed, while no such differences were found in MAP+ abusers. There were no significant differences in reaction time (RT) and error rate between each group.

Conclusion

This is the first study to examine psychosis relationships between ERP time course and performance on an addiction Stroop task in MA abusers with or without psychosis. These findings support the association between attentional bias measured by the MA addiction Stroop task and N200 component as well as indicate the possibility of using this cognitive task in combination with ERP technology to detect psychosis factors among abstinent MA abusers.

A generalizable functional connectivity signature characterizes brain dysfunction and links to rTMS treatment response in cocaine use disorder

Cocaine use disorder (CUD) is a prevalent substance abuse disorder, and repetitive transcranial magnetic stimulation (rTMS) has shown potential in reducing cocaine cravings. However, a robust and replicable biomarker for CUD phenotyping is lacking, and the association between CUD brain phenotypes and treatment response remains unclear. Our study successfully established a cross-validated functional connectivity signature for accurate CUD phenotyping, using resting-state functional magnetic resonance imaging from a discovery cohort, and demonstrated its generalizability in an independent replication cohort. We identified phenotyping FCs involving increased connectivity between the visual network and dorsal attention network, and between the frontoparietal control network and ventral attention network, as well as decreased connectivity between the default mode network and limbic network in CUD patients compared to healthy controls. These abnormal connections correlated significantly with other drug use history and cognitive dysfunctions, e.g., non-planning impulsivity. We further confirmed the prognostic potential of the identified discriminative FCs for rTMS treatment response in CUD patients and found that the treatment-predictive FCs mainly involved the frontoparietal control and default mode networks. Our findings provide new insights into the neurobiological mechanisms of CUD and the association between CUD phenotypes and rTMS treatment response, offering promising targets for future therapeutic development.

Polysubstance addiction and psychiatric, somatic comorbidities among 7,989 individuals with cocaine use disorder: a latent class analysis

Aims

We performed a latent class analysis (LCA) in a sample ascertained for addiction phenotypes to investigate cocaine use disorder (CoUD) subgroups related to polysubstance addiction (PSA) patterns and characterized their differences with respect to psychiatric and somatic comorbidities.

Design

Cross-sectional study.

Setting

United States.

Participants

Adult participants aged 18-76, 39% female, 47% African American, 36% European American with a lifetime DSM-5 diagnosis of CoUD (N=7,989) enrolled in the Yale-Penn cohort. The control group included 2,952 Yale-Penn participants who did not meet for alcohol, cannabis, cocaine, opioid, or tobacco use disorders.

Measurements

Psychiatric disorders and related traits were assessed via the Semi-structured Assessment for Drug Dependence and Alcoholism. These features included substance use disorders (SUD), family history of substance use, sociodemographic information, traumatic events, suicidal behaviors, psychopathology, and medical history. LCA was conducted using diagnoses and diagnostic criteria of alcohol, cannabis, opioid, and tobacco use disorders.

Findings

Our LCA identified three subgroups of PSA (i.e., low, 17%; intermediate, 38%; high, 45%) among 7,989 CoUD participants. While these subgroups varied by age, sex, and racial-ethnic distribution (p<0.001), there was no difference on education or income (p>0.05). After accounting for sex, age, and race-ethnicity, the CoUD subgroup with high PSA had higher odds of antisocial personality disorder (OR=21.96 vs. 6.39, difference-p=8.08×10 -6 ), agoraphobia (OR=4.58 vs. 2.05, difference-p=7.04×10 -4 ), mixed bipolar episode (OR=10.36 vs. 2.61, difference-p=7.04×10 -4 ), posttraumatic stress disorder (OR=11.54 vs. 5.86, difference-p=2.67×10 -4 ), antidepressant medication use (OR=13.49 vs. 8.02, difference-p=1.42×10 -4 ), and sexually transmitted diseases (OR=5.92 vs. 3.38, difference-p=1.81×10 -5 ) than the low-PSA CoUD subgroup.

Conclusions

We found different patterns of PSA in association with psychiatric and somatic comorbidities among CoUD cases within the Yale-Penn cohort. These findings underscore the importance of modeling PSA severity and comorbidities when examining the clinical, molecular, and neuroimaging correlates of CoUD.