Contingency management is efficacious and improves outcomes in cocaine patients with pretreatment marijuana use

Background

Marijuana use is common in patients seeking treatment for cocaine use. Nevertheless, few studies have examined effects of marijuana use on treatment outcomes in general, and even fewer with respect to contingency management (CM) treatment, which has been criticized for potentially increasing non-reinforced drug use.

Methods

Data from three randomized clinical trials of CM versus standard treatment (ST) in cocaine-abusing patients were examined ( [Petry et al., 2004], [Petry et al., 2005a] and [Petry et al., 2006a]; N = 393) to assess effects of pretreatment marijuana use on outcomes. Patients were divided into two groups: (1) no self-reported marijuana use (No Pre-M; n = 315) and (2) any self-reported marijuana use (Pre-M; n = 78) in the 30 days pretreatment.

Results

CM was especially efficacious in enhancing retention in Pre-M patients such that retention nearly doubled among Pre-M patients assigned to CM versus those assigned to ST. In contrast, CM exerted only modest benefits on retention in No Pre-M patients. Pretreatment marijuana use was not related to during-treatment abstinence from cocaine, opioids, and alcohol, or abstinence at a Month 9 follow-up. However, CM treatment and longest duration of abstinence achieved during treatment were significant predictors of Month 9 abstinence. Pre-M patients also evidenced more improvements in drug problems over time when randomized to CM.

Conclusions

CM was especially efficacious in facilitating retention and improving severity of drug-related problems in those who used marijuana in the month before initiating treatment.     

Early adolescent cocaine use as determined by hair analysis in a prenatal cocaine exposure cohort

Background

Preclinical and other research suggest that youth with prenatal cocaine exposure (PCE) may be at high risk for cocaine use due to both altered brain development and exposure to unhealthy environments.

Methods

Participants are early adolescents who were prospectively enrolled in a longitudinal study of PCE prior to or at birth. Hair samples were collected from the youth at ages 10½ and 12½ (N = 263). Samples were analyzed for cocaine and its metabolites using ELISA screening with gas chromatography/mass spectroscopy (GC/MS) confirmation of positive samples. Statistical analyses included comparisons between the hair-positive and hair-negative groups on risk and protective factors chosen a priori as well as hierarchical logistical regression analyses to predict membership in the hair-positive group.

Results

Hair samples were positive for cocaine use for 14% (n = 36) of the tested cohort. Exactly half of the hair-positive preteens had a history of PCE. Group comparisons revealed that hair-negative youth had significantly higher IQ scores at age 10½; the hair-positive youth had greater availability of cigarettes, alcohol, and other drugs in the home; caregivers with more alcohol problems and depressive symptoms; less nurturing home environments; and less positive attachment to their primary caregivers and peers. The caregivers of the hair-positive preteens reported that the youth displayed more externalizing and social problems, and the hair-positive youth endorsed more experimentation with cigarettes, alcohol, and/or other drugs. Mental health problems, peer drug use, exposure to violence, and neighborhood characteristics did not differ between the groups. Regression analyses showed that the availability of drugs in the home had the greatest predictive value for hair-positive group membership while higher IQ, more nurturing home environments, and positive attachment to caregivers or peers exerted some protective effect.

Conclusion

The results do not support a direct relationship between PCE and early adolescent experimentation with cocaine. Proximal risk and protective factors—those associated with the home environment and preteens' caregivers—were more closely related to early cocaine use than more distal factors such as neighborhood characteristics. Consistent with theories of adolescent problem behavior, the data demonstrate the complexity of predicting pre-adolescent drug use and identify a number of individual and contextual factors that could serve as important foci for intervention.     

Prenatal and postnatal cocaine exposure predict teen cocaine use

Preclinical studies have identified alterations in cocaine and alcohol self-administration and behavioral responses to pharmacological challenges in adolescent offspring following prenatal exposure. To date, no published human studies have evaluated the relation between prenatal cocaine exposure and postnatal adolescent cocaine use. Human studies of prenatal cocaine-exposed children have also noted an increase in behaviors previously associated with substance use/abuse in teens and young adults, specifically childhood and teen externalizing behaviors, impulsivity, and attention problems. Despite these findings, human research has not addressed prior prenatal exposure as a potential predictor of teen drug use behavior. The purpose of this study was to evaluate the relations between prenatal cocaine exposure and teen cocaine use in a prospective longitudinal cohort (n = 316) that permitted extensive control for child, parent and community risk factors. Logistic regression analyses and Structural Equation Modeling revealed that both prenatal exposure and postnatal parent/caregiver cocaine use were uniquely related to teen use of cocaine at age 14 years. Teen cocaine use was also directly predicted by teen community violence exposure and caregiver negativity, and was indirectly related to teen community drug exposure. These data provide further evidence of the importance of prenatal exposure, family and community factors in the intergenerational transmission of teen/young adult substance abuse/use.     

Beliefs and attitudes regarding drug treatment: Application of the Theory of Planned Behavior in African-American cocaine users

Background

The Theory of Planned Behavior (TPB) can provide insights into perceived need for cocaine treatment among African American cocaine users.

Methods

A cross-sectional community sample of 400 (50% rural) not-in-treatment African-American cocaine users was identified through respondent-driven sampling in one urban and two rural counties in Arkansas. Measures included self-reports of attitudes and beliefs about cocaine treatment, perceived need and perceived effectiveness of treatment, and positive and negative cocaine expectancies. Normative beliefs were measured by perceived stigma and consequences of stigma regarding drug use and drug treatment. Perceived control was measured by readiness for treatment, prior drug treatment, and perceived ability to cut down on cocaine use without treatment.

Findings

Multiple regression analysis found that older age (standardized regression coefficient β = 0.15, P < 0.001), rural residence (β = − 0.09, P = 0.025), effectiveness of treatment (β = 0.39, P < 0.001), negative cocaine expectancies (β = 0.138, P = 0.003), experiences of rejection (β = 0.18, P < 0.001), need for secrecy (β = 0.12, P = 0.002), and readiness for treatment (β = 0.15, P < 0.001) were independently associated with perceived need for cocaine treatment.

Conclusions

TPB is a relevant model for understanding perceived need for treatment among African-American cocaine users. Research has shown perceived need to be a major correlate of treatment participation. Study results should be applicable for designing interventions to encourage treatment participation.     

Enhancing brief cognitive-behavioral therapy with motivational enhancement techniques in cocaine users

Background

We investigated the impact of enhancing brief cognitive-behavioral therapy with motivational interviewing techniques for cocaine abuse or dependence, using a focused intervention paradigm.

Methods

Participants (n = 74) who met current criteria for cocaine abuse or dependence were randomized to three-session cognitive-behavioral therapy (CBT) or three-session enhanced CBT (MET + CBT), which included an initial session of motivational enhancement therapy (MET). Outcome measures included treatment retention, process measures (e.g., commitment to abstinence, satisfaction with treatment), and cocaine use.

Results

Participants who received the MET + CBT intervention attended more drug treatment sessions following the study interventions, reported significantly greater desire for abstinence and expectation of success, and they expected greater difficulty in maintaining abstinence compared to the CBT condition. There were no differences across treatment conditions on cocaine use.

Conclusions

These findings offer mixed support for the addition of MET as an adjunctive approach to CBT for cocaine users. In addition, the study provides evidence for the feasibility of using short-term studies to test the effects of specific treatment components or refinements on measures of therapy process and outcome.     

Preliminary evidence for normalization of risk taking by modafinil in chronic cocaine users

Modafinil, a wake-promoting agent used to treat sleep disorders, is thought to enhance cognition. Although modafinil has shown promise as a pharmacotherapy for the treatment of cocaine dependence, it is unknown to what extent cognitive effects may play a role in such treatment. We examined the effect of modafinil on the Balloon Analogue Risk Task (BART), a behavioral measure in which higher scores are purported to reflect a greater propensity for risk-taking. Thirty cocaine dependent individuals, enrolled in a randomized clinical trial of modafinil 400 mg (n = 12) versus placebo (n = 18), were administered the BART during the second week of inpatient treatment for cocaine dependence. A comparison cohort of healthy participants (n = 19) performed the BART under similar conditions. Modafinil treatment was associated with significantly higher BART scores (p = 0.01), which were comparable to scores in healthy persons. BART scores in placebo treated participants were much lower than previously reported in healthy participants, and lower than those observed in the comparison cohort. As propensity toward risk taking is typically associated with higher BART scores as well as increased risk for substance use, our findings may reflect a novel aspect of cognitive impairment related to chronic cocaine use. Notably, the low BART scores reflect highly suboptimal performance on the task, and the observed effect of modafinil may indicate a normalization of this impairment and have implications for treatment outcome.     

Early-onset drug use and risk for drug dependence problems

There is substantial evidence that alcohol, tobacco, and cannabis dependence problems surface more quickly when use of these drugs starts before adulthood, but the evidence based on other internationally regulated drugs (e.g., cocaine) is meager. With focus on an interval of up to 24 months following first drug use, we examine drug-specific and age-specific variation in profiles of early-emerging clinical features associated with drug dependence. Based upon the United States National Surveys on Drug Use and Health (NSDUH) conducted in 2000–2002, the risk of experiencing drug dependence problems was robustly greater for adolescent recent-onset users of cocaine, psychostimulant drugs other than cocaine, analgesics, anxiolytic medicines, inhalants drugs, and cannabis, as compared to adult recent-onset users (odds ratio = 1.5–4.3, p < 0.05). This was not the case for the NSDUH hallucinogens group (e.g., LSD). The adolescent onset associated excess risk was not constant across all clinical features. Our evidence suggests promoting earlier detection and interventions, as well as greater parent and peer awareness of drug dependence clinical features that may develop early among young people who have just started using drugs.     

Concurrent validity of cocaine and sedative dependence diagnoses in opioid-dependent outpatients

The present study evaluated the relationship between diagnoses of cocaine and sedative dependence and drug use early in treatment among opioid-dependent patients in methadone substitution therapy. New admissions (n = 138) were assessed via the Structured Clinical Interview for the DSM III-R (SCID) for presence of Axis I and Axis II disorders and followed for five weeks on standard methadone maintenance. Patients submitted urines three times per week tested for opioids, cocaine, and benzodiazepines. Patients diagnosed with current cocaine dependence (n = 90) submitted a higher proportion of cocaine-positive urines (M = 0.84) than patients diagnosed with past cocaine dependence (n = 32; M =0.28) and those diagnosed with no cocaine use disorder (n = 14; M = 0.12), P < 0.001. Current cocaine dependence diagnosis accounted for 52% of the cocaine use variance. Patients exhibiting current sedative dependence (n = 25) submitted a higher proportion of benzodiazepine-positive urines (M = 0.60) than patients with past sedative dependence (n = 44; M = 0.20) and those with no sedative use disorder (n = 60; M = 0.05), P < 0.001. Current sedative dependence diagnosis accounted for 37% of the benzodiazepine use variance. Lifetime major depression (12%) and antisocial personality disorder (39%) were the most common nonsubstance use comorbid diagnoses. Axis I nonsubstance use disorder was associated with benzodiazepine use, while Axis II disorder was associated with both benzodiazepine and cocaine use early in treatment (P < 0.05). These data demonstrate the concurrent validity of DSM-III-R cocaine and benzodiazepine use diagnoses, and support the potentially important relationship between drug use and other psychiatric disorders.     

A comparison of motivations for use among users of crack cocaine and cocaine powder in a sample of simultaneous cocaine and alcohol users

This study examined the motivations for using cocaine and alcohol comparing those who primarily smoked crack and those who primarily used cocaine powder when using simultaneously with alcohol. Motivations examined included: 1) to cope with a negative affect, 2) enhancement, 3) to be social and 4) to conform. The research design was a cross-sectional study in which clients in treatment for cocaine and alcohol problems completed a self-administered questionnaire about their substance use. Among those who primarily smoked crack or snorted cocaine when also using alcohol (n = 153), there were 93 participants who reported primarily snorting cocaine and 60 participants who primarily reported smoking crack. Bivariate analyses found that those who primarily smoked crack reported lower social motivations to use alcohol and cocaine. When adjusting for other covariates in a multivariate analysis, social motivation was still significantly different between groups. Additionally, those who primarily smoked crack were more likely to be older, report higher cocaine dependence severity, be unemployed and were less likely to have completed some post-secondary education, than those who primarily snorted cocaine. No differences were found in enhancement, coping or conformity motivations between the two groups. These results suggest that simultaneous cocaine and alcohol use may have social importance to those who primarily snort cocaine, but that this importance is less evident to those who smoke crack. Consequently, future studies examining motivations for simultaneous cocaine and alcohol use should distinguish between different routes of cocaine administration.     

Estimated effect of prenatal cocaine exposure on examiner-rated behavior at age 7 years

Prenatal cocaine exposure has been linked to increased child behavior difficulties in some studies but not others.

Objective

The primary aim was to estimate the relationship between in utero cocaine exposure and child behavioral functioning at age 7 years with ratings made by blinded examiners during a structured testing session. A second aim was to examine whether caregiver drug use and psychological problems might mediate suspected relationships between prenatal cocaine exposure and aspects of examiner-rated behavior.

Methods

407 children (212 cocaine-exposed, 195 non-exposed) participating in the longitudinal Miami Prenatal Cocaine Study (MPCS) were rated with regard to their behavior during a neuropsychological assessment conducted at age 7 years. Raters were trained research psychometricians blinded to drug exposure status. Individual behavioral items were summarized and the cocaine-behavior relationship was estimated within the context of latent variable modeling, using Mplus software.

Results

Two latent variables, Behavioral Regulation and Sociability, were derived via exploratory latent structure analysis with promax rotation. Prenatal cocaine exposure, statistically controlling for child sex, test age, and prenatal exposure to alcohol, tobacco, and marijuana, was associated with Behavioral Regulation (estimated slope ß = − 0.25; 95% CI = − 0.48, − 0.02; p = 0.04) but not Sociability (estimated slope ß = − 0.03; 95% CI = − 0.26, 0.20; p = 0.79). Neither postnatal drug use by caregivers nor the severity of their psychological problems at age 5 follow-up predicted levels of child Behavioral Regulation or Sociability at age 7 years (p > 0.10).

Conclusions

Examiner ratings of child behavior at age 7 revealed less optimal behavioral regulation for prenatally cocaine-exposed compared to non-exposed children, in contrast with what had been previously found from parent-report data. This evidence highlights the potential value of trained observers in assessing behavioral outcomes of children exposed in utero to drugs and other toxicants.     

Psychosocial treatments for cocaine dependence: the role of depressive symptoms

Background

The association between cocaine use and depression has been frequently observed. However, less is known about the significance of depression in the treatment of cocaine use disorders. This study examined possible interrelations between drug use and depression severity among cocaine-dependent patients in psychosocial treatments for cocaine dependence.

Methods

Monthly assessed drug use and depression severity scores of N = 487 patients during 6-month psychosocial treatments for cocaine dependence were analyzed using hybrid latent growth models.

Results

Results indicated a moderate but statistically significant (z = 3.13, p < .01) influence of depression severity on increased drug use in the upcoming month, whereas drug use did not affect future depression severity.

Conclusions

Findings suggest that depression symptoms are an important predictor of drug use outcomes during psychosocial treatments for cocaine dependence and, hence, underline the importance of adequately addressing depression symptoms to improve treatment outcomes.     

Sex differences in sleep and sleep-dependent learning in abstinent cocaine users

Sleep and sleep-dependent learning are impaired in male cocaine users during abstinence, but for female users little is known. Cocaine dependent men (n = 12) and women (n = 14), and control participants (n = 19) participated in this study of sleep and sleep-dependent learning. Cocaine users were assessed at 3, 10 and 20 days of abstinence and controls were studied over one night. Total sleep time, sleep efficiency and overnight motor learning were the main outcome measures. Cocaine dependent men compared to women exhibited deteriorations in sleep time, sleep efficiency, and overnight learning as abstinence progressed from 3 to 20 days. At abstinence day 3, cocaine dependent men and women were no different than control participants in the main outcomes. However, there were significant differences between cocaine men at abstinence day 20 and controls in sleep time and sleep-dependent learning, but no differences between controls and cocaine dependent women. There is growing evidence that sleep disturbances are associated with cocaine abuse and abstinence and have functional consequences that may be relevant to the development of effective treatments. The absence of sleep disturbances in women suggests a need to understand the mechanisms underlying these differences, as such knowledge could lead to novel therapies in cocaine dependence.     

Risk factors for progression to regular injection drug use among street-involved youth in a Canadian setting

Background

Street-involved youth are at high risk for experimenting with injection drug use; however, little attention has been given to identifying the factors that predict progression to on-going injecting.

Methods

Logistic regression was used to identify factors associated with progression to injecting weekly on a regular basis among a Canadian cohort of street-involved youth.

Results

Among our sample of 405 youth who had initiated injecting at baseline or during study observation, the median age was 22 years (interquartile range [IQR] = 21–24), and 72% (293) reported becoming a regular injector at some point after their first injection experience. Of these, the majority (n = 186, 63%) reported doing so within a month of initiating injection drug use. In multivariate analysis, the drug used at the first injection initiation event (opiates vs. cocaine vs. methamphetamine vs. other; all p > 0.05) was not associated with progression; however, younger age at first injection (adjusted odds ratio [AOR] = 1.13), a history of childhood physical abuse (AOR = 1.81), prior regular use of the drug first injected (AOR = 1.77), and having a sexual partner present at the first injection event (AOR = 2.65) independently predicted progression to regular injecting.

Conclusion

These data highlight how quickly youth progress to become regular injectors after experimentation. Findings indicate that addressing childhood trauma and interventions such as evidence-based youth focused addiction treatment that could prevent or delay regular non-injection drug use, may reduce progression to regular injection drug use among this population.     

Patterns of substance use among Argentinean adolescents and analysis of the effect of age at first alcohol use on substance use behaviors

Objective

The present study used an empirically based method to characterize substance use in a sample of Argentinean adolescents and analyzed the association between age at drinking onset and substance use behaviors. Differences in alcohol expectancies and personality traits as a function of different patterns of substance use were also explored.

Method

Data were obtained from 583 adolescents aged 13–18 years (M = 15.01 years; SD = 1.5 years; 59.5% female) from the city of Cordoba, Argentina. Alcohol, tobacco, and drug use and age at first alcohol use were measured. Personality traits, including extroversion, conscientiousness, impulsivity, and aggression, and positive and negative alcohol expectancies were assessed. Latent Class Analysis was applied to examine the structure of five co-occurring substance use behaviors: frequency of alcohol use, quantity of alcohol use, prevalence of drunkenness episodes, tobacco use, and drug use.

Results

Latent Class Analysis revealed five distinct patterns of substance use. The classes differed in substance use behaviors, personality traits, and alcohol expectancies. Adolescents with early drinking onset were more likely to show heavier alcohol use, more drunkenness episodes, and more drug use than adolescents with late drinking onset.

Conclusions

Latent Class Analysis allowed the detection of groups of adolescents with distinct patterns of substance use. These groups exhibited significantly different personality and alcohol expectancy profiles, likely representing subgroups who are at greater risk for developing alcohol-related problems.     

The effects of prenatal cocaine on language development at 10 years of age

Objective

To examine the long term effects of prenatal cocaine exposure (PCE) on the language development of 10-year-old children utilizing a prospective design, controlling for confounding drug and environmental factors.

Participants

Children exposed to cocaine in utero (PCE; n = 175) and non-exposed children (NCE; n = 175) were followed prospectively to 10 years of age and were compared on language subscales of the Test of Language Development-Intermediate 3rd Edition (TOLD-I:3) and phonological processing as measured by the Comprehensive Test of Phonological Processing (CTOPP).

Methods

Multivariate analysis of covariance (MANCOVA), linear regression, and logistic regressions were used to evaluate the relationship of prenatal cocaine exposure to language development, while controlling for confounders.

Results

After controlling for confounding variables, prenatal cocaine effects were observed for specific aspects of language including syntax (Sentence Combining subtest of the TOLD-I:3, p = 0.001), semantics (Malopropism subtest of the TOLD-I:3, p = 0.05) and phonological processing (Phonological Awareness subscale, p = 0.01). The caregiver factors of vocabulary, HOME, and psychological symptoms also had consistent effects on language subtests and phonological processing scores. Children with PCE who experienced foster or adoptive care had enhanced language development compared to those living with birth mothers or in relative care. Cocaine exposed girls had lower scores on the phonological awareness subscale of the CTOPP than non-exposed girls.

Conclusions

PCE has subtle effects on specific aspects of language development and phonological processing at age 10, even after controlling for confounding variables. Environmental factors (i.e., postnatal lead exposure, home environment, and caregiver vocabulary and psychological symptoms) also impact language skills at 10 years. Adoptive or foster care appears to enrich PCE children's linguistic environment and protects children against language delay in the PCE sample.     

Differences in self-reported and behavioral measures of impulsivity in recreational and dependent cocaine users

Background

Dependent cocaine users consistently display increased trait impulsivity on self-report questionnaires and less consistently exhibit elevated motor impulsivity in some behavioral tasks. However, trait and behavioral impulsivity measures have rarely been investigated in recreational users. Therefore, we examined self-reported trait and motor impulsivities in recreational and dependent cocaine users to clarify the role of impulse control in cocaine addiction and non-dependent cocaine use.

Methods

We investigated relatively pure recreational (n = 68) and dependent (n = 30) cocaine users, as well as psychostimulant-naïve controls (n = 68), with self-report questionnaires (Barratt Impulsiveness Scale 11; Temperament and Character Inventory) and behavioral tasks (Rapid Visual Information Processing Task; Stop-Signal Task).

Results

Compared with controls, recreational and dependent cocaine users displayed higher trait impulsivity and novelty seeking scores on self-report questionnaires. Trait impulsivity scores were strongly associated with an increased number of symptoms of depression and attention deficit hyperactivity disorder and correlated significantly with long-term cocaine intake parameters. By contrast, none of the behavioral motor impulsivity measures showed significant group effects or correlated with cocaine use parameters. The correlations among the self-report measures were high, but self-reports were scarcely correlated with behavioral task measures.

Conclusions

These findings suggest that relatively pure cocaine users already display increased trait impulsivity at a recreational level of use. However, the results do not indicate any cocaine-related elevation of behavioral impulsivity in terms of motor or response inhibition. In summary, our data imply that elevated trait impulsivity is not a specific feature of dependent cocaine use.     

Effects of 14-day treatment with the schedule III anorectic phendimetrazine on choice between cocaine and food in rhesus monkeys

Background

The clinical utility of monoamine releasers such as phenmetrazine or d-amphetamine as candidate agonist medications for cocaine dependence is hindered by their high abuse liability. Phendimetrazine is a clinically available schedule III anorectic that functions as a prodrug for phenmetrazine and thus may have lower abuse liability. This study determined the effects of continuous 14-day treatment with phendimetrazine on cocaine vs. food choice in rhesus monkeys (N = 4).

Methods

Responding was maintained under a concurrent schedule of food delivery (1-g pellets, fixed-ratio 100 schedule) and cocaine injections (0–0.1 mg/kg/injection, fixed-ratio 10 schedule). Cocaine choice dose–effect curves were determined daily before and during 14-day periods of continuous intravenous treatment with saline or (+)-phendimetrazine (0.32–1.0 mg/kg/h). Effects of 14-day treatment with (+)-phenmetrazine (0.1–0.32 mg/kg/h; N = 5) and d-amphetamine (0.032–0.1 mg/kg/h; N = 6) were also examined for comparison.

Results

During saline treatment, food was primarily chosen during availability of low cocaine doses (0, 0.0032, and 0.01 mg/kg/injection), and cocaine was primarily chosen during availability of higher cocaine doses (0.032 and 0.1 mg/kg/injection). Phendimetrazine initially decreased overall responding without significantly altering cocaine choice. Over the course of 14 days, tolerance developed to rate decreasing effects, and phendimetrazine dose-dependently decreased cocaine choice (significant at 0.032 mg/kg/injection cocaine). Phenmetrazine and d-amphetamine produced qualitatively similar effects.

Conclusions

These results demonstrate that phendimetrazine can produce significant, though modest, reductions in cocaine choice in rhesus monkeys. Phendimetrazine may be especially suitable as a candidate medication for human studies because of its schedule III clinical availability.     

Cocaine abuse versus cocaine dependence: Cocaine self-administration and pharmacodynamic response in the human laboratory

Cocaine has high abuse liability but only a subset of individuals who experiment with it develop dependence. The DSM-IV (APA. Diagnostic and Statistical Manual of Mental Disorders DSM-IV-R. American Psychiatric Association, Washington, DC, 2000) provides criteria for diagnosing cocaine abuse and cocaine dependence as distinct disorders- the latter characterized by additional symptoms related to loss of control over drug use. In this study, two groups of cocaine users (n = 8/group), matched on demographic factors and length of cocaine use history and meeting criteria for either cocaine abuse (CocAb) or cocaine dependence (CocDep), were compared on (1) measures related to impulsivity and sensation seeking, (2) response to experimenter-administered cocaine (0, 12.5, 25 and 50 mg/70 kg, i.v.), and (3) cocaine self-administration using a Relapse Choice and a Progressive Ratio Procedure (0, 12.5 and 25 mg/70 kg, i.v.). Groups did not differ on impulsivity or sensation seeking scores. After experimenter-administered cocaine, the CocAb group reported feeling more suspicious and observers rated them significantly higher on unpleasant effects (e.g., irritability, difficulty concentrating). In contrast, the CocDep group reported significantly greater desire for cocaine, which was sustained over the course of the study, and gave higher street value estimates for cocaine (p < 0.05). While cocaine self-administration was dose-related and generally comparable across the two procedures, the CocDep users chose to take significantly more cocaine than the CocAb users. These data suggest that, while regular long-term users of cocaine with cocaine abuse or dependence diagnoses cannot be distinguished by trait measures related to impulsivity, they do exhibit significant differences with regard to cocaine-directed behavior and response to cocaine administration.     

A comparison of treatment outcomes for adolescent community reinforcement approach participants with and without co-occurring problems

This study examined the relationship between Adolescent Community Reinforcement Approach (A-CRA) participation with treatment engagement, retention, and satisfaction, and with substance use and emotional problem outcomes. Participants had substance use disorders (SUD) only or co-occurring substance use and psychiatric problems. Those with co-occurring problems reported more days of substance use and emotional problems at intake to treatment than those with SUD only. All groups received equivalent exposure to A-CRA during treatment implementation. At the 12-month follow-up, adolescents classified as externalizers (n = 468) or those with both externalizing and internalizing problems (n = 674) had significantly greater improvement in their days of abstinence and substance problems relative to adolescents with substance use disorders only (n = 666). Additionally, adolescents reporting symptoms of internalizing (n = 154), externalizing, or both externalizing and internalizing disorders had significantly greater improvements in days of emotional problems relative to adolescents with SUD only.