DD represents a common issue in clinical practice, with relevant effects on symptoms, course and treatment of disease. It's often associated with negative outcome as a greater severity of symptoms and resistance to drug treatment.

To assess how the characteristics (sociodemographic, clinical and related to substance abuse) of patients discharged with DD have changed taking into account the FA occurred in three different five-year periods (1990–1994, 2000–2004, 2005–2009). We also compared the characteristics of patients discharged with only psychiatric diagnosis with those of patients with DD to look for possible risk factors for abuse among people with psychiatric illness.

We conducted a retrospective study of medical records of patients at FA to our Institute in three different periods. We divided the patients discharged with DD from those discharged with only psychiatric diagnosis.

Among the FA occurred in the periods examined we noticed an increase of DD cases (12% from 1990 to 1994, 21% 2000–2004, 28% 2005–2009). The incidence of each diagnosis was changed in several years, but each time the diseases more represented remain schizophrenic or affective psychosis and personality disorders. Alcohol is the most widely used psychotropic drug in each period. There is also a progressive increase in the abuse of cannabis, cocaine and in the incidence of multi-drug abusers. Compared with patients discharged with only a psychiatric diagnosis, patients with DD were more frequently:male, younger, unmarried, unemployed, with legal issues, grown up in a family with serious problems, and history of etero-aggressive episodes.

Due to continued increase in cases of DD, we want to highlight the importance of early identification of cases of comorbidity in order to provide adequate treatment and support.