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

INTRODUCTION: 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.

MATERIAL AND METHODS: 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.

RESULTS: 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.

CONCLUSIONS: 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.