Disturbo bipolare e abuso di sostanze. Una doppia diagnosi con un substrato comune

Summary Objective The aim of this paper is to define and test the hypothesis that emotional insta- bility, in its various expressions within the bipolar spectrum, shares with drug addiction a common substrate. This type of dual diagnosis would come to costi- tute the most probable association under an epidemiological standpoint, due to the presence of a converging risk, i.e., the clinical form where impulsive and dysphoric symptomatology are most prominent. Methods This view was adopted with a series of logical observations supported by data in literature. Drug addiction is a mental disorder acquired through the repeated expo- sure to specific substances and expressed with an uncontrolled desire for the same drugs. Addictive psychopathology refers to elements which were already defined in general psychiatry and which pertain to instinctuality and impulsiveness. Dual diagnosis reflects the probability of a combined course of two psychiatric disor- ders, hence a longitudinal association which suggests a common structure. The syndromes belonging to the bipolar spectrum present psychopathological features consistent with the drive to use substances and with vulnerability to continuous abuse. Clinical attention to the attenuated forms of the disorder, with particular reference to hypomania, to temperament and to psychopathy assimilated to cyclothymia, is crucial for assessing the impact and prevalence of the combina- tion between bipolarity and substance use. Regarding the two poles of affectivity, it is the expansive-exploratory setting rather than the inhibited-depressive one to found an input risk on the pathogenic course leading from recreational use to drug addiction. The good response to anti-addiction treatment correlates with emotional improvement, whereas persistent dysphoria is a relapse predictor. Surprisingly, but consistently with our hypothesis, drugs which provide for addic- tion control (opiate agonists) appear also to be independently efficacious on emotional instability. Hence, dual diagnosis bipolar individuals may draw an amplified benefit from methadone monotherapy, which is specular with respect to the amplified damage that the association between the two disorders entails in the absence of treatment.