Pay for Performance and Treatment Outcome in Agonist Treatment for Opioid Use Disorder.

BACKGROUND AND OBJECTIVES: Pay for performance (P4P) models have become more popular in reimbursement for medical services, including treatment for substance use disorders. However, studies have not examined whether P4P has an impact on treatment outcome in the individual in opioid agonist treatment (OAT). Thus, the present study was conducted at the individual level, rather than the programmatic level, to determine whether meeting the P4P early engagement criteria (four services in the initial 14 days of treatment and/or eight services within the initial 30 days of treatment) resulted in reduced opioid, benzodiazepine, and cocaine use. METHODS: We performed a retrospective study of 63 patients enrolled in OAT for opioid use disorder. χ2 analyses were conducted crossing P4P early engagement criteria status and urine drug screen (UDS) results for opioid, cocaine, and/or benzodiazepine use at 6 and 12 months postadmission. Methadone dosage and treatment retention were also considered. The odds ratio was used to determine the directionality of significant results. RESULTS: Significant relationships were revealed between patients meeting 30-day P4P early engagement criteria and opioid negative UDS, and with retention in treatment at 6 and 12 months. Methadone dosage was significant at a 6-month follow-up. DISCUSSION AND CONCLUSIONS: Since significant associations between opioid use and P4P as well as opioid use and methadone dose were revealed, findings partially supported hypothesis. SCIENTIFIC SIGNIFICANCE: P4P and methadone dosage may have some benefit to individuals in OAT in attaining short-term abstinence from opioids. P4P may be less useful in helping individuals achieve abstinence from other substances of abuse. (Am J Addict 2020;00:00-00).

Alcohol and other drug use in older adults: results from a community needs assessment.

BACKGROUND: With the "Baby Boomer" generation reaching older adulthood, substance abuse treatment providers find themselves needing to address the unique needs of this population. Heavy drinking in adults ages 65 and over is strongly correlated with depression, anxiety, decreased social support, and poor health. However, while alcohol misuse has been shown to be predictive of a lower quality of life in older adults, the generalizability of these findings to urban dwelling, lower socioeconomic status individuals remains unclear. AIMS: To identify potential treatment needs of this population, a city-funded needs assessment was conducted. METHODS: Subjects were 249 individuals (44% male) who voluntarily completed measures of quality of life (QOL), depression, and substance abuse. Measures used included the Psychological General Well-Being Schedule, the Geriatric Depression Scale-15, and the Alcohol Use Disorders Identification Test (AUDIT). RESULTS: Alcohol or substance abuse was reported by over 20% of respondents, with 3.4% of respondents engaged in maladaptive alcohol use. Scores on the AUDIT were predictive of increased depression (r = - .209, p = .01), anxiety (r = - .201, p = .002), lower general well-being (r = - .154, p = .019), and decreased self-control (r = - .157, p = .017). DISCUSSION: A substantial percentage of the sample reported alcohol and substance misuse. Alcohol use was predictive of depression, global psychological distress, and decreased quality of life. CONCLUSIONS: This needs assessment reinforces findings from previous studies and addresses the added dimension of examining this in an urban, lower socioeconomic population.

Impact of cannabis use during stabilization on methadone maintenance treatment.

BACKGROUND AND OBJECTIVES: Illicit drug use, particularly of cannabis, is common among opiate-dependent individuals and has the potential to impact treatment in a negative manner. METHODS: To examine this, patterns of cannabis use prior to and during methadone maintenance treatment (MMT) were examined to assess possible cannabis-related effects on MMT, particularly during methadone stabilization. Retrospective chart analysis was used to examine outpatient records of patients undergoing MMT (n = 91), focusing specifically on past and present cannabis use and its association with opiate abstinence, methadone dose stabilization, and treatment compliance. RESULTS: Objective rates of cannabis use were high during methadone induction, dropping significantly following dose stabilization. History of cannabis use correlated with cannabis use during MMT but did not negatively impact the methadone induction process. Pilot data also suggested that objective ratings of opiate withdrawal decrease in MMT patients using cannabis during stabilization. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: The present findings may point to novel interventions to be employed during treatment for opiate dependence that specifically target cannabinoid-opioid system interactions.

The influence of intake urinalysis, psychopathology measures, and menstrual cycle phase on treatment compliance.

Drug abuse among women is a societal health problem which has received greater attention in recent years. Studies examining sex differences in drug abuse have shown consistent differences between males and females. In the current study, we retrospectively examined 75 treatment-seeking females to determine the relationships between intake measurements of psychopathology, intake urinalysis, menstrual cycle phase at admission, and treatment compliance. Our results support a relationship among these variables and a potential relationship between menstrual cycle phase and anxiety level is discussed. These results support the need for the development of individually tailored treatment programs.

The genetic determinants of smoking.

Dependence on tobacco, like many other drug dependencies, is a complex behavior with both genetic and environmental factors contributing to the variance. The heritability estimates for smoking in twin studies have ranged from 46 to 84%, indicating a substantial genetic component to smoking. Candidate gene studies have detected functional polymorphisms in genes coding for the cytochrome P450 enzymes, and variations in these genes that lead to more rapid nicotine metabolism have been implicated in smoking. Similarly, smoking has been associated with polymorphisms in dopaminergic genes that may influence the dopamine receptor number and/or function. Animal experiments have localized specific subunits of the nicotinic receptors that may mediate the reinforcing properties of nicotine and have investigated their role in nicotine dependence. However, environmental factors have also been found to contribute to the risk of initiation and persistence of smoking. We review the scientific evidence that supports a role for genetic influences on smoking, discuss the specific genetic and neurobiological mechanisms that may mediate susceptibility to nicotine dependence, identify possible gene/environmental interactions that may be important in understanding smoking behavior, and suggest directions for future research. Insights into the genetic contributions to smoking can potentially lead to more effective strategies to reduce smoking.

Differences in platelet serotonin transporter sites between African-American tobacco smokers and non-smokers.

RATIONALE: The serotonin transporter (5HTT) regulates the magnitude and duration of serotonergic neurotransmission. Although nicotine and other constituents of tobacco smoke may influence serotonin turnover among animals, few studies have examined whether smoking is associated with alteration in 5HTT in humans. OBJECTIVE: We investigated whether tobacco smokers and non-smokers differed in platelet tritiated paroxetine binding, a measure of 5HTT sites, and whether severity of nicotine dependence (ND) was related to 5HTT measures. METHODS: Tritiated paroxetine binding sites on platelets were assayed in 26 African-American smokers and 30 non-smokers. Severity of smoking was assessed using the Fagerstrom Test for Nicotine Dependence (FTND). Relationships between FTND scores and maximum number of transporter sites (B(max)) and affinity constant (K(d)) of paroxetine binding were determined. RESULTS: B(max) values showed a significant negative correlation with FTND scores (rho=-0.28, P<0.01). Notably, smokers with higher ND had significantly lower B(max) compared to those with lower ND and non-smokers; the latter two groups did not differ in B(max) ( F=3.92, P<0.05). Smokers scored higher on impulsivity than non-smokers, however, behavioral variables did not influence the relationship of smoking with B(max). Age, gender and K(d) values were not associated with smoking or B(max). CONCLUSIONS: Smoking, in particular higher nicotine dependence, appears to be correlated with decreased density of platelet 5HTT sites in African-Americans. The nature of the relationship and whether similar changes occur in the brain merit further investigation.

No association between polymorphisms in the serotonin transporter gene and susceptibility to cocaine dependence among African-American individuals.

Genetic research of cocaine abuse has been relatively limited among the African-American population. Since the serotonin transporter (5HTT) may be involved in modulating effects of cocaine, we investigated whether allelic variants of the 5HTT gene may confer susceptibility to cocaine dependence among African-American individuals. One hundred and fifty-six cocaine-dependent subjects and 82 controls were studied. Polymerase chain reaction-based genotyping of a variable-number-tandem-repeat (VNTR) marker yielded three alleles designated 12, 10 and 9. Genotype and allele frequencies were compared using chi-square analyses. We found no differences between subjects and controls with respect to genotype distribution (cocaine: 12/12 = 50%, 10/12 = 35.3%, 10/10 = 13.5%, 9/12 = 1.3%; controls: 12/12 = 42.7%, 10/12 = 39.0%, 10/10 = 17.1%, 9/12 = 1.2%). Similarly, allele frequencies of the VNTR marker did not differ between the two groups (cocaine: 12 = 68.3%, 10 = 31.1%, 9 = 0.6%; controls: 12 = 62.8%, 10 = 36.6%, 9 = 0.6%). Our findings do not seem to support a relationship between VNTR polymorphisms and cocaine dependence among African-American patients. Further studies involving larger samples are required to confirm our results.

Serotonin transporter polymorphisms and measures of impulsivity, aggression, and sensation seeking among African-American cocaine-dependent individuals.

Considerable evidence indicates that serotonergic mechanisms, particularly the serotonin transporter (5HTT), may mediate central effects of cocaine and may also be involved in impulsive and aggressive behavior. We investigated whether polymorphisms in the 5HTT gene were related to traits of impulsivity, sensation seeking, and aggression among cocaine abusers. Standardized measures of these personality traits were obtained in a sample of 105 severely affected cocaine-dependent African-American subjects and 44 African-American controls. Two polymorphisms of the 5HTT gene were examined involving the 5' promoter (5HTTLPR) region and a 17 base pair variable-number-tandem-repeat (VNTR) marker among cocaine patients. No significant relationships were observed between polymorphic variants of the 5HTTLPR and VNTR regions and scores on any of the trait measures. Similarly, demographic variables and measures of severity of substance use and depression were unrelated to allele frequencies or genotype distributions of the variants among cocaine patients. As expected, cocaine patients scored significantly higher on total scores of impulsivity, aggression, and sensation seeking compared to controls. The findings do not seem to support an association between these polymorphisms in the 5HTT gene and impulsive-aggressive traits among cocaine-dependent African-American individuals.

Serotonin transporter (5-HTT) gene polymorphisms and susceptibility to cocaine dependence among African-American individuals.

Studies indicate that the serotonin system, particularly the serotonin transporter (5-HTT), may modulate the central effects of cocaine. We investigated whether a polymorphism in the 5' promotor region (5-HTTLPR) of the 5-HTT gene confers susceptibility to cocaine dependence. One hundred and ninety-seven cocaine-dependent African-American subjects and 101 controls were studied. Polymerase chain reaction based genotyping of a biallelic repeat polymorphism in the 5' promotor region yielded 2 alleles containing 484 (S) and 528 bp (L) repeats, respectively. There were no significant differences between controls of European background (n = 40) and African-American controls (n = 61) in distribution of genotypes (European: LL = 32.5%, LS = 40.0%, SS = 27.5%; African-American: LL = 27.9%, LS = 57.4%, SS = 14.7%) (chi(2) = 3.60, df = 2, p = 0.16) or allele frequencies (European: L = 52.5%, S = 47.5%; African-American: L = 56.6%, S = 43.4%) (chi(2) = 2.21, df = 1, p = 0.13). When cocaine patients were compared to an ethnically diverse control group (n = 101), frequencies of the L variant (65.0%) were significantly higher while the S variant (35.0%) was less frequent among cocaine patients compared to controls (L = 53.9%, S = 46.1%) (chi(2) = 6.83, df = 1, p < 0.01). Similarly, there were more cocaine patients with the LL genotype (41.1%) and less with the SS genotype (11.2%) compared to controls (LL = 29.7%, SS = 21.8%) (chi(2) = 7.43, df = 2, p < 0.05). However, after restricting controls to African-American individuals only (n = 61), cocaine subjects and controls did not differ significantly with respect to genotype distribution (chi(2) = 4.24, df = 2, p = 0.12) or allele frequencies (chi(2) = 2.83, df = 1, p = 0.10). In conclusion, although comparisons with a heterogeneous control group indicated a possible association between allelic variants of 5-HTTLPR and cocaine dependence among African-American cocaine subjects, this relationship was not observed when the control group was limited to African-American people only. Our findings need to be confirmed on larger samples of ethnically matched individuals.

Gender differences in cue exposure reactivity and 9-month outcome.

Gender differences have been shown to be related to the course of cocaine dependence and treatment. While previous research has shown cue exposure procedures to be somewhat effective at reducing reactivity of substance dependent individuals to drug related stimuli, the few studies that have examined gender differences in craving and cue-reactivity have yielded equivocal results. We have recently demonstrated that an active cue-exposure procedure that featured cocaine-dependent individuals receiving immediate feedback about their level of physiological arousal following videotaped exposure to cocaine-related stimuli was capable of positively influencing in-treatment (helplessness, abstinence efficacy) as well as 9-month followup outcome (i.e., urinalysis) indices (Sterling, R., Gottheil, E., Murphy, J., & Weinstein, S. (2001). Cue exposure and abstinence efficacy. College on Problems of Drug Dependence, Phoenix, AZ, June 17, 2001). The purpose of the present study was to determine whether differential in-treatment or 9-month followup outcomes were obtained for male and female study participants. Subjects in this study were 81 individuals (47 male/34 female) who met DSM-IV criteria for cocaine dependence and who had consented to be randomly assigned to either the active cue-exposure or control conditions. Participants were compared along a myriad of pre-treatment, in-treatment, and 9-month followup measures. Other than males reporting more recent employment, there was no obvious systematic pattern of differences on pre-treatment indices. No gender differences in treatment retention were observed. With respect to 9-month followup, no gender differences on measures of addiction severity, psychological functioning, or urinalyses were noted. However males were more "cue-reactive" and more successful at establishing control over their reactivity to the cocaine stimuli. Additional research is needed to determine whether these differences in reactivity can be more clearly defined and utilized positively in a treatment setting.

Predicting treatment-outcome in cocaine dependence from admission urine drug screen and peripheral serotonergic measures.

We investigated whether urine drug screens (UDS) at admission and platelet paroxetine binding, a measure of serotonin transporter sites, were related to outcome measures for cocaine patients in treatment. Tritiated paroxetine binding sites on platelets were assayed and UDS were obtained for 105 African American cocaine-dependent outpatients. Outcome measures included number of negative urines, days in treatment, dropouts, and number of treatment sessions attended. A significant association was found between cocaine-positive UDS at admission and negative urines, treatment retention, dropouts, and treatment sessions; while Bmax values of paroxetine binding (density of serotonin transporter sites) were significantly associated with treatment retention and negative urines. Moreover, UDS and paroxetine binding combined to enhance prediction of retention and abstinence. Although both admission UDS and paroxetine binding seem to contribute individually in predicting outcome of cocaine patients, a combination of the two variables seems to have a stronger effect in terms of predicting treatment-outcome.

Pre-treatment measures of impulsivity, aggression and sensation seeking are associated with treatment outcome for African-American cocaine-dependent patients.

We investigated whether measures of impulsivity, aggression and sensation seeking differed between cocaine-dependent subjects and controls, and whether these measures were related to treatment-outcome for cocaine patients. Pre-treatment assessments of impulsivity (Barratt Impulsivity Scale [BIS]), aggression (Buss-Durkee Hostility Inventory [BDHI]) and sensation seeking (Zuckerman Sensation Seeking Scale [SSS]) were obtained for 141 African-American cocaine-dependent patients entering a 12-week, intensive outpatient treatment program and 60 controls. The outcome measures were number of negative urine drug screens, days in treatment, dropout rates and number of treatment sessions. Cocaine patients reported significantly higher scores on the SSS, the BIS and the BDHI than controls. Furthermore, the SSS scores showed a significantly negative correlation with days in treatment and negative urines, and a significant positive correlation with the dropout rate. The BIS and the BDHI scores were significantly associated with days in treatment and dropout rates respectively. A combination of the three variables contributed significantly toward predicting retention and abstinence. Higher levels of pretreatment impulsivity and aggression and sensation seeking seem to associated with poor treatment outcome for cocaine dependent patients receiving intensive outpatient treatment. Combining these behavioral measures with other clinical predictors may help in early identification of 'poor responders' who may benefit from additional or alternative treatment approaches.

Relationship between platelet serotonin uptake sites and treatment outcome among African-American cocaine dependent individuals.

We investigated whether platelet tritiated paroxetine binding, a measure of serotonin uptake sites differed between cocaine-dependent subjects and controls, and whether paroxetine binding was related to treatment-outcome for cocaine patients. One hundred twenty-five African-American cocaine-dependent individuals receiving outpatient treatment and 44 controls were studied. Tritiated paroxetine binding sites on platelets were assayed and standardized assessments of behavior were performed. The outcome measures were number of negative urine drug screens, days in treatment, dropout rates and number of treatment sessions attended. Cocaine patients had significantly lower Bmax values of paroxetine binding compared to controls. Furthermore, Bmax values showed a significant positive correlation with days in treatment and negative urines. A combination of Bmax and Addiction Severity Index (ASI) employment scores improved the prediction of days in treatment and a combination of Bmax and ASI drug scores enhanced the prediction of negative urines. The findings indicate that serotonergic mechanisms may be involved in cocaine dependence and may influence treatment-outcome among cocaine patients.

Comparison of pretreatment characteristics and treatment outcomes for alcohol-, cocaine-, and multisubstance-dependent patients.

We investigated whether pretreatment characteristics and measures of outcome differed for alcohol-, cocaine-, and multisubstance-dependent patients receiving outpatient substance abuse treatment. One hundred and forty substance dependent individuals (32 alcohol, 76 cocaine, and 32 multisubstance) enrolled in a 12-week outpatient treatment program were compared across measures of addiction severity, personality, and treatment-readiness at admission. In-treatment, end-of-treatment and 9-month follow-up assessments of treatment outcome were then compared across the three groups. Outcome measures included reduction in problem severity, abstinence, retention, number of sessions attended, dropout, and counselor and patient ratings of treatment benefit. At admission, the multisubstance group had a higher proportion of positive urines, reported more severe drug, alcohol and psychiatric problems, and displayed higher impulsivity and anxiety scores than one or both of the other groups. However, multisubstance patients were more treatment ready in terms of adopting a total abstinence orientation than alcohol or cocaine patients. While a significant reduction in symptoms occurred for the total sample during treatment as well as at follow-up, comparisons of outcomes did not consistently favor any particular group. The three groups had equivalent improvements in eleven of fourteen during-treatment and five of seven follow-up measures. Despite pretreatment differences, in severity and treatment-readiness, outcomes were more similar than different for alcohol-, cocaine-, and multisubstance-dependent patients. Clinicians should be cautious about forecasting treatment-outcomes for addicted patients based on their primary substances of abuse.

A Comparison of Medical Symptoms Reported by Cocaine-, Opiate-, and Alcohol-Dependent Patients.

Substance abuse is frequently associated with adverse medical consequences. The differences in medical symptoms reported by 101 alcohol-, 113 cocaine-, and 107 opiate-dependent individuals receiving outpatient treatment were studied using a 134-item questionnaire (MILCOM). Data analysis revealed interesting and unexpected findings, with cocaine patients reporting the fewest total symptoms among the three groups. Moreover, cocaine patients reported significantly fewer CNS and musculoskeletal symptoms compared to both alcohol and opiate patients and significantly fewer GI and urinary symptoms than the alcohol but not the opiate patients. In addition, there were sex- and race-related differences in the pattern of symptoms reported. Women reported significantly more CVS, mood, nose/throat, CNS, skin, and GI symptoms than men. Similarly, Caucasians reported significantly more mood, CNS, nose/throat, head/neck, musculoskeletal, and GI symptoms than African-Americans. The study highlights the influence of drug of choice, gender, and race on medical needs of substance-abusing persons.

Tobacco smoking: current concepts in etiology and treatment.

Tobacco smoking is the most important preventable cause of death and disease. Despite an increased awareness of the addictive nature of smoking and availability of effective treatments, smoking continues to be widespread among individuals with psychiatric disorders. Moreover, mental health professionals remain reluctant to address smoking among their patients for a variety of reasons. Recent research has provided a wealth of data that have shaped the concept of tobacco smoking as a chronic addictive disorder and also demonstrated the efficacy of smoking cessation interventions. This paper reviews the important factors that contribute to smoking and the various pharmacological and psychosocial interventions for smoking cessation from a biopsychosocial perspective. It also makes recommendations for the rational use of these interventions to treat nicotine dependence in individuals with psychiatric disorders.

Methadone maintenance treatment.

Preview Substance abuse, particularly injecting drug use, is receiving increased attention because of its role in the spread of AIDS. Methadone maintenance treatment programs help curb the spread by decreasing injecting drug abuse and by offering HIV testing, counseling, and referral for care of infected patients. Drs DeMaria and Weinstein explain how methadone programs work and what primary care physicians need to know to refer their opiate-dependent patients.

Relationship between tobacco smoking and medical symptoms among cocaine-, alcohol-, and opiate-dependent patients.

Despite widespread use of tobacco by alcohol and drug abusers, the medical effects of smoking remain understudied among such individuals. We investigated the relationship between tobacco smoking and medical symptoms among 87 cocaine-, 98 opiate- and 81 alcohol-dependent individuals receiving outpatient treatment. Smoking status was assessed and medical symptoms were recorded using a standardized 134-item self-report instrument (MILCOM). Almost 79% of patients were tobacco smokers. Analysis of variance revealed a main effect of tobacco smoking on medical symptoms. Smokers reported significantly more symptoms on the total scale as well as on the respiratory, cardiovascular, gastrointestinal, and nose/throat subscales compared to non-smokers. Furthermore, we found a significant interaction between tobacco smoking and substance abuse with respect to medical symptoms. While opiate and alcohol patients who smoked reported more symptoms than those who did not, unexpectedly, cocaine users who smoked reported fewer symptoms than those who did not smoke. While the findings support the link between smoking and medical problems among substance abusers, these effects do not seem to be uniform across various substances of abuse. In particular, cocaine patients seem to be affected differently than alcohol and opiate patients.

Changes in mu opioid receptors and rheological properties of erythrocytes among opioid abusers.

Opioids, reported originally to bind to specific receptors in the brain, now also appear to bind to receptors on blood cells. The high prevalence of anemia among chronic opioid users leads us to propose that chronic opiate use results in elevated mu opioid receptor levels on human erythrocytes and that these receptor changes may affect erythrocyte membrane properties. Blood samples from 17 opioid-dependent subjects (based on the Diagnostic and Statistical Manual of Mental Disorders, 4th edition or DSM-IV) and 15 drug-free controls were assayed for mu opioid receptors on erythrocytes using a flow cytometry immunoassay. Deformability and the hydration status of erythrocytes were studied by ektacytometry. Data were analyzed by independent t-tests, tests of correlation, chi square and cluster analyses. As expected, the percentage of erythrocytes from opioid-dependent subjects with opioid receptors (opioid receptor levels) was significantly higher (47.4 +/- 38.3%) than controls (22.8 +/- 30.1%) (t = 2.01, df = 30, p < 0.05). Also, the opioid-dependent patients showed a wide variation in the percentage of erythrocytes bearing opioid receptors and data analyses of these patients showed two strongly defined clusters. One subgroup consisted of nine individuals with very high receptor levels (mean = 81.5%) while the other had eight patients with low receptor levels (mean = 9.1%) that were not significantly different than the receptor levels of controls. Ektacytometry of opioid dependent patients with high opioid receptor levels showed changes in rheological parameters of erythrocytes, such as deformability index and cellular hydration. For example, a positive correlation was observed between opioid receptor levels and deformability indices among opioid-dependent patients (r = 0.74, p < 0.005). Our findings indicate that the mu opioid receptor is present on human erythrocytes, although with considerable variation in receptor levels, and that the levels of this receptor are significantly elevated with chronic opioid exposure. Moreover, erythrocytes with high opioid receptor levels from chronic opiate users seem to have high deformability. This study may offer clues to the biological properties of peripheral blood cells that may be mediated by mu opioid receptors and lead to a better understanding of some of the clinical effects of opioid use.

Serum prolactin and response to treatment among cocaine-dependent individuals.

Considerable evidence indicates that dopaminergic mechanisms may modulate the central effects of cocaine. We investigated whether basal serum prolactin, a measure of central dopamine activity, differed between cocaine-dependent subjects and controls, and whether prolactin levels among cocaine patients were related to their response to treatment. Eighty-six African-American cocaine-dependent outpatients and 35 African-American controls were studied. Prolactin concentrations in fasting blood samples were assayed by radioimmunoassay. The outcome measures were: number of negative urine drug screens, retention in treatment, counselor ratings of improvement and discharge status. Chi-square tests and independent t-tests were used for data analyses. The basal prolactin(ng/ml) among cocaine patients (9.12 +/- 4.12) was significantly higher compared to controls (7.14 +/- 3.36) (t = 2.52, p < 0.02). Furthermore, the higher prolactin subjects (median prolactin = 7.71) had significantly fewer negative urine screens (p < 0.05) and received less favorable ratings of improvement by counselors (p < 0.01) compared to the lower prolactin group. However, the two groups did not differ significantly in treatment retention (p = 0.13) or discharge status (p = 0.08). The higher basal prolactin among cocaine patients relative to controls may reflect changes in DA activity among cocaine patients. Moreover, higher prolactin seems to be related negatively with certain measures of response to treatment among cocaine patients.