Clinical Textbook of Addictive Disorders 3rd ed - R. Frances, S. Miller, A. Mack (Guilford, 2005) WW

11. Polysubstance Use, Abuse, and Dependence 257alcohol, cocaine, marijuana, or opiate abuse or dependence. The authors founda consistent 60:40 ratio of Type A to Type B for each of the drug groups, suggestingclusters of personality characteristics that are independent of drug ofchoice. Similarly, in 370 patients attending treatment for alcoholism, cocaine,or opiate dependence, Ball and colleagues (1998) replicated the A-B classificationand also found a 60:40 Type A to Type B ratio. Type A substance abusershad less multiple drug use, as well as an older age of onset, fewer years of heavyuse, less family history of substance abuse, less impulsivity, and less severe substanceabuse. Type B substance abusers tended to be more severe than type Aabusers, scoring higher on the personality dimensions of neuroticism, noveltyseeking, and harm avoidance. They also had a higher prevalence of multiplesubstance abuse, an earlier age of onset, more childhood psychiatric symptoms,higher incidence of all Cluster B personality disorders, and more frequent familyhistory of substance abuse (Ball et al., 1998). The Type B profile is quitecommon in methadone patients, in whom there is a greater prevalence ofASPD than in the general population (Brooner, King, Kidorf, Schmidt, &Bigelow, 1997; Rounsaville et al., 1991).Compared to drug abusers who are categorized as Type A, Type B is predictiveof having multiple SUDs. This is an important refinement in the assessmentof drug abusers; since multiple SUD does not occur in non-substance-abusingpopulations, this distinction gives some predictive power in the target subpopulationof those with SUD. As described earlier, ASPD in persons with SUDis predictive of multiple SUDs, IDU, and higher severity, and an earlier studyfound that ASPD was one of the best predictors of Type B membership amongcocaine abusers (Ball et al., 1995). However, Ball and colleagues (1998) foundthat the basis for Type A and Type B distinctions in personality dimensions anddisorders among the 370 patients in their study remained much the same whenthe cluster analysis was controlled for presence of ASPD. The typological distinctionis not just of heuristic value—Type B patients have more severe SUDs andrelapse more quickly after addiction treatment as compared with Type A patients(Babor et al., 1992; Ball et al., 1995). In addition, the more frequent family historyof SUD and early onset in Type B patients is consistent with a stronger geneticcomponent compared with late-onset Type A patients.GENETIC AND FAMILY STUDIESVulnerability to substance abuse has general genetic, familial, and nonfamilialenvironmental factors, as well as factors that appear to be specific to a particularclass of substances. A family history of substance abuse is one of the strongestrisk factors for development of a SUD (Merikangas et al., 1998). Studies havedemonstrated that there are genetic influences on the risk for substance abuse(Tsuang et al., 1996) and that, at least among men, abusing one category of