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.