Substance-use disorders in DSM-III-R. Evidence for the dependence syndrome across different psychoactive substances.

Using the newly revised DSM-III-R criteria for substance-abuse diagnoses, we examined dependence syndrome elements among 83 psychiatric patients. The sample included 14 with no history of substance abuse. The remainder abused alcohol (52), sedatives (31), hallucinogens (12), stimulants (33), cannabis (44), cocaine (52), or opiates (47). Many patients (52) had abused more than one type of drug. Ten items assessing the proposed dependence symptoms for each type of drug were factor-analysed. The dependence syndrome items formed a single factor for opiates, cocaine, and alcohol, but not for other drugs. When the items were combined into cumulative scales, they had excellent internal consistency. Furthermore, they formed good approximations of unidimensional Guttman scales on which higher scores indicated greater syndrome severity. The items associated with higher scores differed across drugs, with opiates having the most striking differences from the other substances. Medical-psychosocial consequences were relatively independent of the dependence syndrome, although alcohol and cocaine dependence had some association with other problem areas. These findings support the utility of a common dependence syndrome concept for drugs of abuse as well as alcohol, and provide empirical support for the current revision of the DSM-III diagnostic criteria.