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.

Relationship between platelet serotonin uptake sites and measures of impulsivity, aggression, and craving among African-American cocaine abusers.

We investigated whether platelet-tritiated paroxetine binding, a measure of serotonin uptake sites, and behavioral measures of impulsivity, aggression, and craving differed between cocaine-dependent subjects and controls and whether paroxetine binding was related to these behavioral measures. One hundred and five African-American cocaine-dependent outpatients and 44 African-American controls were studied. Tritiated paroxetine binding sites on platelets were assayed, and standardized assessments of impulsivity, aggression, and craving were performed. The Bmax values of paroxetine binding were significantly reduced among cocaine patients compared to controls. Cocaine patients showed significantly higher scores on certain measures of sensation seeking, impulsivity, and aggression as compared to controls. Furthermore, paroxetine binding showed a significant negative correlation with most measures of sensation seeking, impulsivity, and aggression--though not craving--among cocaine patients. Our findings indicate that densities of serotonin uptake sites may be reduced among cocaine abusers and related to impulsive-aggressive behavioral dimensions.

High- and low-structure treatments for substance dependence: role of learned helplessness.

We studied whether pretreatment levels of learned helplessness (LH) were related to outcomes for substance-dependent individuals receiving high-structure, behaviorally oriented (HSB) or low-structure, facilitative (LSF) treatment. The subjects were 120 substance-dependent patients randomly assigned to the HSB or the LSF treatment style for up to 12 weeks of weekly individual counseling. The two groups were compared across pretreatment characteristics as well as in-treatment, end-of- treatment, and 9-month postadmission follow-up outcome measures. Outcomes reflected reduction in problem severity, abstinence, retention, dropout rate, and ratings of treatment benefit. Significant and comparable reductions in symptoms occurred for the HSB and LSF patients both during treatment and at follow-up. Comparisons of other outcomes also did not consistently favor either treatment style. However, significant and consistent interactions were observed between LH and treatment styles with respect to several outcome measures, and these effects were independent of pretreatment levels of depression, addiction severity, and readiness for treatment. Specifically, the more "helpless" patients did significantly better in HSB treatment, whereas the less "helpless" patients had better outcomes in LSF treatment. A matching approach that assigns patients to high- and low-structure treatments based on pretreatment levels of LH might improve treatment outcomes for substance-dependent patients.

Nicotine dependence and treatment outcome among African American cocaine-dependent patients.

Despite a close association between tobacco and cocaine use, few studies have systematically examined whether smoking predicts an adverse outcome for cocaine-dependent patients. We investigated whether severity of nicotine dependence was related to treatment outcome for cocaine-dependent individuals. Standardized assessments of nicotine dependence (Fagerström Test for Nicotine Dependence; FTND), cocaine use, and personality were obtained for 105 African American cocaine-dependent outpatients. Outcome measures included negative urine drug screens, days in treatment, dropout, and number of treatment sessions attended. The sample was stratified into cocaine-positive and cocaine-negative groups based on admission urine drug screens, and relationships between nicotine dependence and outcome measures were examined in each group. In the cocaine-negative group, higher FTND scores were negatively correlated with number of negative urine drug screens during treatment even after controlling for other predictors, whereas FTND scores were not correlated to outcome in the cocaine-positive group. It seems that severity of tobacco use predicts poor outcome for cocaine-dependent patients who are cocaine free at the time of admission into outpatient treatment.

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.

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.

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.

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.