For most cocaine-dependent individuals, standard treatment approaches have not been effective. Although a substantial percentage of cocaine abusers have other psychiatric conditions, knowledge about these groups and appropriate interventions are inadequate. It has been hypothesized that psychiatrically-impaired cocaine abusers may be self-medicating their psychiatric symptoms with psychoactive substances. More effective treatment medications targeted to treat the co-existing psychiatric disorders might reduce or eliminate cocaine use. In order to adequately assess a targeted medication, specific subpopulations must be clearly identified and appropriately diagnosed. Within this application, three cocaine-abusing subpopulations will be evaluated: those with attention deficit hyperactivity disorder (ADHD), those with schizophrenia, and those with personality disorders. Training is planned in several areas: modification of structured diagnostic assessments; epidemiology; laboratory assessment of drug-drug/medication-drug interactions; methodology of treatment trials; and instruction in statistics and experimental design. A recently funded NIDA grant will provide a large part of the initial research training. First, the prevalence of ADHD in cocaine abusers seeking treatment will be determined. Second, research will be carried in the laboratory to determine if subjective responses to cocaine are differentially altered in subjects diagnosed with ADHD and whether potential treatment medications, e.g., methylphenidate and desipramine, alter cocaine's reinforcing effects. As a direct outgrowth of the prevalence and laboratory studies, outpatient studies will be carried out to assess the efficacy of these medications in treatment-seeking cocaine abusers with ADHD. In addition to this population, other psychiatric subpopulations will be studied. Despite an increased focus on individuals with schizophrenia who abuse cocaine, there are few reported successful treatment strategies for this population. A medication which could effectively treat both disorders would be ideal. Outpatient pilot treatment studies will be conducted to evaluate the effectiveness of flupenthixol and risperidone in cocaine abusers with schizophrenia. Finally, the diagnostic and clinical issues of personality disorders will be investigated in cocaine abusers. It may be that those with persistent personality disorders independent of drug use do worse in treatment. Using a modified personality assessment, prevalence rates of personality disorders in cocaine abusers, as well as treatment outcome, will be determined. Combined, these areas of training will provide a broad expertise such that future studies can be competently designed to effectively match patients to the appropriate treatment interventions.
