Coexistence between personality disorders and substance use disorder. Madrid study about prevalence of dual pathology

Personality disorders (PD) and substance use disorders (SUD) have a high prevalence and an important health and socioeconomic impact so, it is interesting to study the relationship between them. The objectives of the study are: to compare the prevalence of SUD between patients with and without diagnosis of PD, to analyze if any PD is related to the SUD, and if a specific PD is associated with a specific SUD.

Cross-sectional study in 837 patients from centers of attention to drug addiction and mental health in Madrid, Spain. The Mini International Neuropsychiatric Interview (MINI) and the Personality Diagnostic Questionnaire-4+ (PDQ4+) are used to detect mental disorder and PD, respectively.

SUD is significantly higher in antisocial PD (p<0.01); sedative (p<0.01) and alcohol (p<0.05) use disorder in borderline PD; cocaine (p<0.05) and alcohol (p<0.01) use disorder in paranoid PD; and alcohol use disorder in histrionic PD (p<0.01). The SUD for cocaine is lower in obsessive- compulsive PD (p<0.05) and depressive PD (p<0.01). There is a positive correlation between the number of PD of a subject and the number of SUD that it presents. The risk of an alcohol [OR of 1,08 CI (1,01-1,16)] or sedatives [OR of 1,08 CI (1,001-1,17)] use disorders increases if an individual presents more than one type of PD.

There is not differences of SUD prevalence between PD and not PD groups. We found an association between SUD and PD of cluster B (antisocial, borderline and histrionic) and also with paranoid PD. The SUD are more common among man with the exception of sedatives.