No association between D3 dopamine receptor (DRD3) alleles and cocaine dependence

Cocaine is thought to act in the brain primarily by blocking dopamine re-uptake. The dopamine D3 receptor (genetic locus DRD3) is localized to brain regions that have been implicated in the reinforcing effects of a number of substances of abuse, including cocaine. The DRD3 coding region contains a polymorphism identifiable as a polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). This polymorphism leads to an amino acid substitution at position 9 in the extracellular N-terminus of the D3 dopamine receptor. We examined alleles of the DRD3 gene in cocaine dependence using a genetic association strategy in samples of 62 white and 62 black cocaine-dependent individuals. Comparisons were made with local (Connecticut) control subjects for both groups, and with a larger sample of literature controls (for the white subjects) and a contrast group of schizophrenic patients (for the black subjects). No association was found between cocaine dependence and DRD3 alleles in either group (Bonferroni corrected). There was a significant difference in allele frequency between whites and blacks. These results are consistent with no role for genetic variation of the D3 dopamine receptor in susceptibility to cocaine dependence.

Influence of retroactive disability payments on recipients' compliance with substance abuse treatment

OBJECTIVE

This study examined whether substance abusers who received large retroactive payments from Social Security disability programs were more likely to terminate residential treatment precipitously than those who did not receive payments.

METHODS

The records of 43 patients of a long-term residential treatment facility who received disability payments at some point during their treatment stay were blindly examined. Twenty-six of these patients received a large one-time retroactive payment representing money that accumulated during processing of the claims. To test the hypothesis that receipt of such a payment would lead to precipitous discharge, a survival regression model was used. A control group of nonrecipient patients was sampled at a comparable point in treatment.

RESULTS

Subjects in the recipient group were significantly more likely to have unplanned discharges than those in the comparison group.

CONCLUSIONS

These preliminary data suggest that large cash infusions can be disruptive to the course of treatment for substance abusers.

Personality disorders and associated features in cocaine-dependent inpatients

Previous research has shown a high prevalence of comorbid personality disorders among individuals seeking treatment for cocaine dependence. We studied axis II disorders (using the Structured Clinical Interview for DSM-III-R Personality Disorders [SCID-II]) in 50 patients admitted for inpatient rehabilitation. All patients met lifetime criteria for cocaine dependence and reported cocaine use during the month before admission. Seventy percent of patients met criteria for at least one axis II diagnosis; the mean number of axis II diagnoses among these patients was 2.54 (range, one to six). The most common axis II diagnosis was borderline (34% of all patients), followed by antisocial and narcissistic (each 28%), avoidant and paranoid (each 22%), obsessive-compulsive (16%), and dependent (10%). To evaluate the relationship between comorbid personality pathology, substance abuse, and other psychiatric symptomatology, patients were divided into two groups based on whether they received an axis II disorder diagnosis. The groups did not differ on substance abuse variables. However, there were significant group differences on a measure of psychosis proneness and in the number of comorbid depressive and anxiety disorder diagnoses. These results are consistent with other studies of personality disorders in substance abuse patients, and suggest that it may be clinically useful to characterize cocaine-dependent patients with respect to comorbid axis II disorders.

Use of imipramine for attention deficit disorder in a borderline patient

A subcategory of patients with borderline personality disorder (BPD) who also meet criteria for attention deficit disorder (ADD) has recently been described. The present case involves a young man with BPD and ADD who failed to respond to methylphenidate but experienced a marked reversal of anxiety, explosiveness, restlessness, and affective lability when treated with imipramine. Tricyclics may prove to be helpful in borderlines who also meet criteria for ADD.