Dual diagnosis (substance used disorders (SUD) and mental illness) represents 3% of general population. Among United States population, 42.3% of SUD patients have psychiatric troubles (without tobacco). Moreover, SUD can concern all psychoactive substances (PAS) or illicit PAS only named “dual disorder with drugs” (DDD).

A quantitative analysis of DDD data from January 2013 to July 2014 of two epidemiological tools has been performed: PMSI database (Programme Médicalisé des Systeme d’Information) hospital discharge data is made up of data providing medical information for all patients discharged in Paris public hospital system (AP–HP) and NOT'S is a vigilance database of spontaneous NOTifications of drug abuse and dependence. We propose a descriptive analysis of DDD in Paris metropolitan area.

With PMSI, 9.2% of SUD inpatients (n = 617) have DDD, with mean age of 46 years (62% of men). In comparison, NOT'S reports 36% of SUD with DDD (n = 302) with mean age of 39.5 years (68% of men). Suicide attempt is also listed and reach 23% of cases.

These two databases (Fig. 1) show the difficulty of DDD diagnosis with the discordance in results. DDD miss in PMSI database since addictovigilance database shows a first prevalence of DDD. Despite the high rates of DDD, the problem is often under diagnosed by clinicians practising. It is also important to promote the collaboration among health care workers (addictologist and psychiatrist) because these patients require intensive mental and substance abuse care.

The authors have not supplied their declaration of competing interest.