Due to the high prevalence of personality disorders, especially borderline and narcissistic personalities in men drug users, the aim of the present study was to investigate clustering of personality disorders based on nature and character dimensions in men drug users.

A sample of 400 men was selected by purposive sampling from men drug users that referred to various specialized psychiatric centers and addiction treatment clinics in Tabriz in 1398. Participants completed the questionnaires on nature and character, narcissistic personality, and the personality assessment - borderline characteristic scale. Data were analyzed using a two-stage cluster analysis test.

The results showed that narcissistic personality traits in men with drug use disorders could be categorized into two clusters based on nature and character dimensions, including grandiose narcissistic (including high innovative characteristic, damage avoidance and self-efficacy and low cooperation) and vulnerable narcissistic (including low innovative characteristic, reward dependency and persistence and high cooperation). Also, borderline personality traits in men with drug use disorders can be categorized into four clusters based on nature and character dimensions in the form of four border clusters self-destructive borderline (including high innovative characteristic and self-direction and low dependence on rewards, persistence and cooperation), impulsive borderline (including high innovative characteristic and damage avoidance, and low reward dependency, persistence and self-sufficiency), discouraged borderline (including low innovative characteristic, damage avoidance and persistence and high self-direction and cooperation) and petulant borderline (including low innovative characteristic, damage avoidance, persistence, reward dependency and cooperation and high self-direction).

The findings of the present study showed that although personality disorders are one of the important companions of drug use disorders, but due to the existence of different types of borderline and narcissistic personality disorders and the combination of various nature and characteristics in each of their subgroups, mental intervention strategies should be applied to prevent recurrence and assist to stop drug abuse should be applied with these characteristics in mind.