It's known that adherence to treatment is a key factor in the treatment of addictions. The presence of comorbid substance dependence disorder and other psychiatric disorder is very high. Comorbid psychiatric disorders interfere with adherence to drug treatment and detoxification.

To analyze the percentage of patients who had a voluntary discharge to Hospital Detoxification Unit and to describe sociodemographic, clinical and diagnostic test characteristics.

We descriptively studied drug dependents patients admitted to our Detoxification Unit from June 2008 to August 2012. Data was gathered at admission on demographic (age), clinical (main abused drug, psychiatric comorbidities, polydrug users, binge consumption previous intake) and alcoholtest and/or urinalysis. Results from patients with and without voluntary discharge were compared.

The study sample included 469 patients (77.7% men, average age 38.3 ± 9). 10.7% of the patients had voluntary discharge. We found significant differences between voluntary discharge and the non-voluntary discharge group on younger people (37,6 vs 40,42,p < 0,05), on heroine as main drug of abuse (40% vs 13,4%, p < 0,0001) and psychiatric comorbidities (60,8% vs 39,2%,p = 0,02), being psychotic disorders (26% vs 13,6%,p < 0,02) and borderline personality disorder (56% vs 29,4%,p < 0,0001) the most significant. Also patients who had binge consumption previous intake (84% vs 56.6%,p < 0.0001) and patients with positive urinalysis(84% vs 58.2%,p < 0.0001) had more voluntary discharge. Patients with comorbid depressive disorders had non-voluntary discharge(6% vs 18.4%,p < 0.02).

Few patients had a voluntary discharge. Younger people, opiate dependence, having psychotic and borderline personality co morbidity, binge consumption previous intake and positive urinalysis might be considered as risk factors for voluntary discharge.