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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    • "Although this subtyping is applied to all substance classes, it has had little psychometric research. Our mixture analyses that provided both latent categories and dimensional estimates, however, did not find support that 'tolerance' or 'withdrawal' assessed a more severe end of opioid use problems than others, suggesting that this subtyping for dependence may need to be evaluated (Wu et al. 2009a). "
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    Psychological Medicine 03/2011; 41(3):653-64. DOI:10.1017/S0033291710000954 · 5.43 Impact Factor
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    • "Nothing could be further from the truth. Quite on the contrary, however, many substance-abusing or substance-dependent individuals are faced with the facts that they do live in social isolation , that social isolation has been found to be associated with an increased risk of, for example, intermediate amphetamine dependence [with odds ratios of 4.1 for 'separated, divorced or widowed' and of 7.8 for 'never married' versus 'married/cohabitating'; (Wu et al. 2009)], and that social isolation has been found to be a negative predictor for substance abuse treatment outcome (Mertens & Weisner 2000; Moos, Nichol & Moos 2002). "
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    Addiction Biology 02/2011; 16(2):273-84. DOI:10.1111/j.1369-1600.2010.00285.x · 5.93 Impact Factor
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    • "LCA can thus help elucidate different sets of nonmedical opioid users by classifying them into subgroups according to drug use patterns. We have demonstrated the use of LCA for enhancing understanding of subtypes of drug dependence (Wu, Blazer et al., 2009) and the extent of heterogeneity in polysubstance use among ecstasy users (Wu, Parrott et al., 2009). "
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