Predictors of cocaine use disorder treatment outcomes: a systematic review

BACKGROUND

Psychosocial approaches are the first-line treatments for cocaine dependence, although they still present high dropout and relapse rates. Thus, there is a pressing need to understand which variables influence treatment outcomes to improve current treatments and prevent dropout and relapse rates. The aim of this study is to explore predictors of treatment retention and abstinence in CUD.

METHODS

This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched three databases-PubMed, PsychINFO and Web of Science-for randomized clinical trials (RCTs) published in English and Spanish from database inception through April 1, 2023. We selected all studies that met the inclusion criteria (adults aged ≥ 18, outpatient treatment, CUD as main addiction, and no severe mental illness) to obtain data for the narrative synthesis addressing cocaine abstinence and treatment retention as main outcome variables. After data extraction was completed, risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials (RoB-2).

RESULTS

A total of 566 studies were screened, and, of those, 32 RCTs were included in the synthesis. Younger age, more years of cocaine use, and craving levels were significant predictors of relapse and treatment dropout. Fewer withdrawal symptoms, greater baseline abstinence, greater treatment engagement, and more self-efficacy were all predictors of longer duration of abstinence. The role of impulsivity as a predictor of CUD is unclear due to conflicting data, although the evidence generally suggests that higher impulsivity scores can predict more severe addiction and withdrawal symptoms, and earlier discontinuation of treatment.

CONCLUSION

Current evidence indicates which variables have a direct influence on treatment outcomes, including well-studied cocaine use-related variables. However, additional variables, such as genetic markers, appear to have a high impact on treatment outcomes and need further study.

SYSTEMATIC REVIEW REGISTRATION

This systematic review is registered at PROSPERO (ID: CRD42021271847). This study was funded by the Spanish Ministry of Science, Innovation and Universities, Instituto Carlos III (ISCIII) (FIS PI20/00929) and FEDER funds and Fundació Privada Hospital de la Santa Creu i Sant Pau (Pla d'acció social 2020).

CBT4CBT web-based add-on treatment for cocaine use disorder: Study protocol for a randomized controlled trial

Background

Cocaine use disorder (CUD) is a chronic condition that presents high relapse rates and treatment dropouts. Web-based interventions have proven to be effective when optimizing face-to-face treatments in different mental health conditions and have the potential to optimize current CUD treatments. However, web-based interventions in addictive behaviors are still limited. The aim of this study is to evaluate whether adding a web-based cognitive behavioral therapy (i.e., CBT4CBT) to standard CUD treatment, improves treatment outcomes in a Spanish sample of patients with severe CUD (which requires inpatient treatment). Additionally, we aim to explore predictive factors of treatment response and treatment gender-related differences.

Methods

All individuals coming for inpatient cocaine detoxification who meet the inclusion criteria will have the possibility to be part of the study. The participants of this open-label randomized controlled clinical trial (RCT) will be allocated to treatment as usual (TAU) or TAU+CBT4CBT after the hospitalization for cocaine detoxification. During the inpatient treatment they will all receive an individualized psychological intervention. There will be six time point assessments: at 48-72 h of starting inpatient treatment, at the end of inpatient treatment and before starting day care and outpatient treatment, at the end of the 8 weeks CTB4CBT / TAU arm treatment and at three follow-up time points (1-, 3-, and 6-months post-treatment).

Discussion

To the best of our knowledge, this is the first RCT that explores the efficacy of adding a web-based cognitive behavioral therapy to usual CUD treatment with patients of a clinical sample in Europe.

Trial registration

IIBSP-CTB-2020-116, NCT05207228. Submitted 8^th of April 2021, posted 26 ^st of January 2022. https://clinicaltrials.gov/ct2/show/NCT05207228?cond=Cocaine+Use+Disorder&draw=2&rank=1.

Factors associated with the absence of cocaine craving in treatment-seeking individuals during inpatient cocaine detoxification

BACKGROUND

Anecdotal evidence suggests a substantial proportion of individuals with cocaine use disorder do not report craving during inpatient detoxification.

OBJECTIVE

To examine prevalence and clinical correlates of consistent absence of cocaine craving among inpatients during detoxification. We hypothesized that craving absence would be associated with less severity of cocaine use, depression, and anxiety. Alternative explanations were also explored.

METHODS

Craving absence (i.e., non-cravers) was defined as a daily score of zero across two separate craving visual analogue scales in each of the inpatient days. Participants scoring ≥1 on ≥1 day were considered cravers. Severity of cocaine use disorder as well as in-treatment depression and anxiety were assessed. Alternative contributors included presence of cocaine and other substances in urine at admission, in-treatment prescription of psychotropic medications, treatment motivation, executive function, interoception, and social desirability.

RESULTS

Eighty-seven participants (78.2% males) met criteria as either non-cravers (n = 29; 33.3%) or cravers (n = 58; 66.7%). Mean length of admission in non-cravers and cravers was, respectively, 10.83 and 13.16 days. Binary logistic regression model showed that non-cravers scored significantly lower than cravers on cocaine use during last month before treatment (OR, 95% CI; 0.902, 0.839-0.970), in-treatment depression (OR, 95% CI; 0.794, 0.659-0.956), and in-treatment prescribing of antipsychotics (OR, 95% CI; 0.109, 0.014-0.823). Model prediction accuracy was 88.9%.

CONCLUSIONS

One in three patients undergoing inpatient detoxification experienced absence of craving, linked to less pretreatment cocaine use, better mood, and decreased administration of antipsychotics. Findings may inform pretreatment strategies and improve treatment cost-effectiveness.

Cocaine addiction is associated with abnormal prefrontal function, increased striatal connectivity and sensitivity to monetary incentives, and decreased connectivity outside the human reward circuit

Cocaine addiction has been associated with increased sensitivity of the human reward circuit to drug-related stimuli. However, the capacity of non-drug incentives to engage this network is poorly understood. Here, we characterized the functional sensitivity to monetary incentives and the structural integrity of the human reward circuit in abstinent cocaine-dependent (CD) patients and their matched controls. We assessed the BOLD response to monetary gains and losses in 30 CD patients and 30 healthy controls performing a lottery task in a magnetic resonance imaging scanner. We measured brain gray matter volume (GMV) using voxel-based morphometry and white matter microstructure using voxel-based fractional anisotropy (FA). Functional data showed that, after monetary incentives, CD patients exhibited higher activation in the ventral striatum than controls. Furthermore, we observed an inverted BOLD response pattern in the prefrontal cortex, with activity being highest after unexpected high gains and lowest after losses. Patients showed increased GMV in the caudate and the orbitofrontal cortex, increased white matter FA in the orbito-striatal pathway but decreased FA in antero-posterior association bundles. Abnormal activation in the prefrontal cortex correlated with GMV and FA increases in the orbitofrontal cortex. While functional abnormalities in the ventral striatum were inversely correlated with abstinence duration, structural alterations were not. In conclusion, results suggest abnormal incentive processing in CD patients with high salience for rewards and punishments in subcortical structures but diminished prefrontal control after adverse outcomes. They further suggest that hypertrophy and hyper-connectivity within the reward circuit, to the expense of connectivity outside this network, characterize cocaine addiction.

Patient perception of methadone dose adequacy in methadone maintenance treatment: The role of perceived participation in dosage decisions

OBJECTIVE

In clinical practice, methadone maintenance treatment (MMT) entails tailoring the methadone dose to the patient's specific needs, thereby individualizing treatment. The aim of this study was to identify the independent factors that may significantly explain methadone dose adequacy from the patient's perspective.

METHOD

Secondary analysis of data collected in a treatment satisfaction survey carried out among a representative sample of MMT patients (n=122) from the region of La Rioja (Spain). As part of the original study protocol, participants completed a comprehensive battery to assess satisfaction with MMT, psychological distress, opinion of methadone as a medication, participation in dosage decisions, and perception of dose adequacy.

RESULTS

Multivariate binary logistic regression showed that the only variable independently associated with the likelihood of a patient perceiving methadone dose as inadequate was the variable perceived-participation in methadone dosage decisions (OR=0.538, 95% CI=0.349-0.828).

CONCLUSION

Patient participation in methadone dosage decisions was predictive of perceived adequacy of methadone dose beyond the contribution of other socio-demographic, clinical, and MMT variables.

PRACTICE IMPLICATIONS

Patient participation in methadone dosage decision-making is valuable for developing a genuinely patient-centred MMT.

Development and validation of the scale to assess satisfaction with medications for addiction treatment-methadone for heroin addiction (SASMAT-METHER)

OBJECTIVE

To develop and examine the psychometric properties of a scale to specifically assess satisfaction with methadone in heroin-dependent patients.

METHODS

The 44-item preliminary version of the scale to assess satisfaction with medications for addiction treatment-methadone for heroin addiction (SASMAT-METHER) was obtained from a pool of items designed to assess satisfaction with any medication-addiction combination. Theoretical domains of the initial SASMAT-METHER were overall satisfaction, pharmacotherapy, initiation, anti-addictive effect on heroin, mental state, physical state, personal functioning, acceptability, and anti-addictive effect on secondary substances. The Treatment Satisfaction Questionnaire for Medication 1.4 version (TSQM 1.4) and the Verona Service Satisfaction Scale for Methadone Treatment (VSSS-MT) were used for concurrent validation. Participants included heroin-dependent patients receiving methadone treatment for at least the last 3 months.

RESULTS

The preliminary version of the SASMAT-METHER scale was completed by 241 patients, with 180 surveys considered suitable for factor analysis. Principal component analysis of these SASMAT-METHER surveys revealed a 3-factor structure that accounted for 40.4% of total variance. Based on similarities between empirically-obtained factors and theoretical domains, factors 1 through 3 were named 'Personal Functioning and Well-Being' (7 items), 'Anti-Addictive Effect on Heroin' (5 items), and 'Anti-Addictive Effect on Other Substances' (5 items). All factors showed good to excellent internal consistency (Cronbach's α: 0.83-0.92) and test-retest reliability (intraclass correlation coefficients: 0.66-0.89). Correlations between overall SASMAT-METHER and TSQM 1.4 scores were stronger (Pearson r=0.69) than correlations between overall SASMAT-METHER and VSSS-MT scores (Pearson r=0.26).

CONCLUSION

These results present evidence for the validity and reliability of SASMAT-METHER.

Psychometric properties of the Spanish version of the Cocaine Selective Severity Assessment to evaluate cocaine withdrawal in treatment-seeking individuals

Reliable and valid assessment of cocaine withdrawal is relevant for treating cocaine-dependent patients. This study examined the psychometric properties of the Spanish version of the Cocaine Selective Severity Assessment (CSSA), an instrument that measures cocaine withdrawal. Participants were 170 cocaine-dependent inpatients receiving detoxification treatment. Principal component analysis revealed a 4-factor structure for CSSA that included the following components: 'Cocaine Craving and Psychological Distress', 'Lethargy', 'Carbohydrate Craving and Irritability', and 'Somatic Depressive Symptoms'. These 4 components accounted for 56.0% of total variance. Internal reliability for these components ranged from unacceptable to good (Chronbach's alpha: 0.87, 0.65, 0.55, and 0.22, respectively). All components except Somatic Depressive Symptoms presented concurrent validity with cocaine use. In summary, while some properties of the Spanish version of the CSSA are satisfactory, such as interpretability of factor structure and test-retest reliability, other properties, such as internal reliability and concurrent validity of some factors, are inadequate.

A hybrid method for quasi-three-dimensional slope stability analysis in a municipal solid waste landfill

Limited space for accommodating the ever increasing mounds of municipal solid waste (MSW) demands the capacity of MSW landfill be maximized by building landfills to greater heights with steeper slopes. This situation has raised concerns regarding the stability of high MSW landfills. A hybrid method for quasi-three-dimensional slope stability analysis based on the finite element stress analysis was applied in a case study at a MSW landfill in north-east Spain. Potential slides can be assumed to be located within the waste mass due to the lack of weak foundation soils and geosynthetic membranes at the landfill base. The only triggering factor of deep-seated slope failure is the higher leachate level and the relatively high and steep slope in the front. The valley-shaped geometry and layered construction procedure at the site make three-dimensional slope stability analyses necessary for this landfill. In the finite element stress analysis, variations of leachate level during construction and continuous settlement of the landfill were taken into account. The "equivalent" three-dimensional factor of safety (FoS) was computed from the individual result of the two-dimensional analysis for a series of evenly spaced cross sections within the potential sliding body. Results indicate that the hybrid method for quasi-three-dimensional slope stability analysis adopted in this paper is capable of locating roughly the spatial position of the potential sliding mass. This easy to manipulate method can serve as an engineering tool in the preliminary estimate of the FoS as well as the approximate position and extent of the potential sliding mass. The result that FoS obtained from three-dimensional analysis increases as much as 50% compared to that from two-dimensional analysis implies the significance of the three-dimensional effect for this study-case. Influences of shear parameters, time elapse after landfill closure, leachate level as well as unit weight of waste on FoS were also investigated in this paper. These sensitivity analyses serve as the guidelines of construction practices and operating procedures for the MSW landfill under study.

Improvements in the production of doubled haploids in durum wheat (Triticum turgidum L.) through isolated microspore culture

The objective of this study was to produce durum wheat doubled haploid (DH) plants through the induction of microspore embryogenesis. The microspore culture technique was improved to maximize production of green plants per spike using three commercial cultivars. Studies on factors such as induction media composition, induction media support and the stage and growth of donor plants were carried out in order to develop an efficient protocol to regenerate green and fertile DH plants. Microspores were plated on a C(17) induction culture medium with ovary co-culture and a supplement of glutathione plus glutamine; 300 g/l Ficoll Type-400 was incorporated to the induction medium support. Donor plants were fertilized with a combination of macro and microelements. With the cultivars 'Ciccio' and 'Claudio' an average of 36.5 and 148.5 fertile plants were produced, respectively, from 1,000 anthers inoculated. This technique was then used to produce fertile DH plants of potential agronomic interest from a collection of ten F(1) crosses involving cultivars of high breeding value. From these crosses 849 green plants were obtained and seed was harvested from 702 plants indicating that 83% of green plants were fertile and therefore were spontaneously DHs. No aneuploid plant was obtained. The 702 plants yielded enough seeds to be field tested. One of the DH lines obtained by microspore embryogenesis, named 'Lanuza', has been sent to the Spanish Plant Variety Office for Registration by the Batlle Seed Company. This protocol can be used instead of the labor-intensive inter-generic crossing with maize as an economically feasible method to obtain DHs for most crosses involving the durum wheat cultivars grown in Spain.

[Cognitive-behavioral therapy for the treatment of cocaine dependence]

The past two decades have been characterized by marked progress in the development of effective cognitive- behavioral therapies for cocaine dependence, for which no generally effective pharmacotherapies have been identified. The increasing literature on the efficacy of several types of cognitive-behavioral therapies (community reinforcement approach plus vouchers, cue exposure treatment, relapse prevention therapy and motivational interviewing) for cocaine use disorders is reviewed, followed by discussion of a number of issues that arise when integrating these cognitive-behavioral interventions into clinical practice. Overall, this review describes a vigorous area of research that has much to contribute to the treatment of cocaine use disorders.

Methadone tapering plus amantadine to detoxify heroin-dependent inpatients with or without an active cocaine use disorder: two randomised controlled trials

The efficacy of methadone tapering plus amantadine to detoxify heroin-dependent patients with or without an active cocaine use disorder was studied in a closed unit with two successive double-blind, placebo-controlled, 14-day trials. In the first trial, 40 heroin-dependent inpatients with an active cocaine use disorder were treated using methadone tapering, as well as amantadine (200-300 mg per day) or placebo. In the second trial, 40 heroin-dependent inpatients without an active cocaine use disorder received the same treatment. In both the trials, amantadine did not have a statistically significant effect on treatment completion, nor did it contribute, in completers, to a more rapid reduction in craving and opiate withdrawal. In the first trial, women were six times more likely than men to be non-completers, and on the last day of treatment, the first trial's completers and non-completers presented a comparable clinical state.

A controlled trial of daily versus thrice-weekly buprenorphine administration for the treatment of opioid dependence

This study was aimed at determining whether thrice-weekly administration of buprenorphine is as effective as daily administration for treating opioid dependence. A total of 60 treatment-seeking opioid addicts were randomly assigned to take buprenorphine tablets sublingually either every day (8 mg) or thrice-weekly (16 mg on Mondays and Wednesdays and 24 mg on Fridays) over the course of a 12-week, double-blind, parallel trial. The buprenorphine dosing schedule had no significant effect on treatment retention. The rates of opioid-positive urine tests were significantly higher among those subjects who were given buprenorphine thrice weekly (58.5%) than among those who took it daily (46.6%). An analysis of the completers did not detect a significant effect of buprenorphine dosing schedule. The results obtained in our clinical trials indicate the advisability of daily doses of buprenorphine, at least at the beginning of a maintenance programme.

Striatal dopaminergic D(2) receptor density measured by [(123)I]iodobenzamide SPECT in the prediction of treatment outcome of alcohol-dependent patients

OBJECTIVE

The authors' goal was to study striatal dopaminergic dopamine 2 (D(2)) receptors as a biological marker of early relapse in detoxified alcoholic patients by using [(123)I]iodobenzamide ([123I]IBZM) single photon emission computed tomography (SPECT).

METHOD

The authors performed [(123)I]IBZM SPECT on 21 alcohol-dependent inpatients during detoxification and on nine healthy volunteers, using the ratios of basal ganglia to occipital lobes for SPECT quantification. Depending on treatment outcome 3 months after hospital discharge, patients were determined to be relapsers or nonrelapsers.

RESULTS

Alcohol-dependent subjects with early relapse (within 3 months after hospital discharge) showed a higher uptake of [(123)I]IBZM in the basal ganglia during detoxification (mean ratio=1.83, SD=0.9) than patients who did not have early relapse (mean ratio=1.69, SD=0.11).

CONCLUSIONS

These results suggest that low levels of dopamine, or an increased density of free striatal dopaminergic D(2) receptors, could be related to early relapse in alcohol-dependent patients. Therefore, [(123)I]IBZM SPECT could become a biological marker of vulnerability to relapse for alcoholic patients in recovery.

[Proposal for improving the integration of drug dependencies in psychiatric nosology]

The classic model of the substance induced psychotic disorder is applicable to the substance dependence. The drugs of abuse produces an organic disorder over basal forebrain systems, which are the biological substrate of desire and impulse control. As a result emerge the specific substance dependence psychopathology.