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.