Are the binary typology models of alcoholism valid in polydrug abusers?

OBJECTIVE To evaluate the dichotomy of type I/II and type A/B alcoholism typologies in opiate-dependent patients with a comorbid alcohol dependence problem (ODP-AP). METHODS The validity assessment process comprised the information regarding the history of alcohol use (internal validity), cognitive-behavioral variables regarding substance use (external validity), and indicators of treatment during 6-month follow-up (predictive validity). RESULTS ODP-AP subjects classified as type II/B presented an early and much more severe drinking problem and a worse clinical prognosis when considering opiate treatment variables as compared with ODP-AP subjects defined as type I/A. Furthermore, type II/B patients endorse more general positive beliefs and expectancies related to the effect of alcohol and tend to drink heavily across several intra- and interpersonal situations as compared with type I/A patients. CONCLUSIONS These findings confirm two different forms of alcohol dependence, recognized as a low-severity/vulnerability subgroup and a high-severity/vulnerability subgroup, in an opiate-dependent population with a lifetime diagnosis of alcohol dependence.