Article

Heterogeneity of Stimulant Dependence: A National Drug Abuse Treatment Clinical Trials Network Study

Department of Psychiatry and Behavioral Sciences, Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina, USA.
American Journal on Addictions (Impact Factor: 1.74). 05/2009; 18(3):206-18. DOI: 10.1080/10550490902787031
Source: PubMed

ABSTRACT We investigated the presence of DSM-IV subtyping for dependence on cocaine and amphetamines (with versus without physical dependence) among outpatient stimulant users enrolled in a multisite study of the Clinical Trials Network (CTN). Three mutually exclusive groups were identified: primary cocaine users (n = 287), primary amphetamine users (n = 99), and dual users (cocaine and amphetamines; n = 29). Distinct subtypes were examined with latent class and logistic regression procedures. Cocaine users were distinct from amphetamine users in age and race/ethnicity. There were four distinct classes of primary cocaine users: non-dependence (15%), compulsive use (14%), tolerance and compulsive use (15%), and physiological dependence (tolerance, withdrawal, and compulsive use; 56%). Three distinct classes of primary amphetamine users were identified: non-dependence (11%), intermediate physiological dependence (31%), and physiological dependence (58%). Regardless of stimulants used, most female users were in the most severe or the physiological dependence group. These results lend support for subtyping dependence in the emerging DSM-V.

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