In substance – related disorders comorbidity refers to any preexisting or following psychological or psychiatric condition that influence the course and prognosis of a patient.

To determine the extent of comorbid substance use and psychiatric disorders among hospitalized in a General Hospital Psychiatric Unit patients and reveal the implications of treatment in such a unit.

All patients hospitalized during a year, were included in the study. Demographics, final diagnosis, substance of use and means of admission (voluntary or involuntary) were recorded.

7.4% of the total of 339 inpatients met the diagnostic criteria of comorbid substance use disorders. Eleven of them were diagnosed with alcohol use disorder comorbidity, 7 with illicit drug use comorbidity and 7 with both legal and illicit drug use comorbidity. Among inpatients with comorbid use disorders male patients had a significantly higher percentage versus females (x2 p < 0.05). Mean age of inpatients with comorbidity was significantly less than the mean age of the sample (t-test p < 0.05). Duration of hospitalization for inpatients with comorbidity was 15.16 ± 12.4 days versus 21.2 ± 18.4 days for the rest of patients (t-test p < 0.05). Concerning the way of admission, 72% of inpatients with comorbid use disorders were involuntary admitted (x2 p < 0.05).

Concerning age, sex and means of admission patients with a psychiatric disorder and substance use disorder comorbidity seem to vary from the rest of inpatients. These parameters are probably associated with serious difficulties in therapeutic compliance and with increased hazard.