Personality Disorders

Subject of this chapter is the often found combination of personality disorders and ­substance abuse disorders. The serious nature of this comorbidity is shown through the discussion of prevalence and epidemiological data. Literature shows that the comorbidity, hampering the diagnostic process, is seen as complicating for treatment planning. Therefore, etiological models that explain the co-occurrence of both disorders are helpful. Several models, among them the Behavioral Disinhibition Pathway, the Stress Reduction Pathway, and the Reward Sensitivity Pathway are described. Next, treatment programs, focusing on one or on both disorders are described, and research results are shown. Finally, clinical implications are described. The most important conclusion drawn is that treatment of dually diagnosed patients with severe problems needs to include both foci, and because of that conclusion, therapists need to be trained to address a range of symptomatic manifestations of personality pathology in the impulse control spectrum.