REDD-PAC Cohort Description: Researching Dual Diagnosis - Prognosis and Characteristics

Evidence from real-world integrated dual diagnosis treatment programs is limited. In 2017 we decided to establish the REDD-PAC cohort with the aim to provide more in-depth information regarding the effect of integrated treatment.

The REDD-PAC cohort includes more than 2,500 patients with dual diagnosis that have been treated at an in-patient department specializing in the integrated treatment of both psychiatric illness and substance use disorder in Denmark in the period from 2002 to 2017. The collected data included information on diagnosis as well as patient-completed questionnaires regarding anxiety, depression, self-worth, and use of substances. Data regarding medications prescribed and administered, weight, height, and blood pressure were also included.

The primary diagnosis was psychosis spectrum disorder (37.0%), followed by affective disorders (18.8%). More than two-thirds of the patients were male, and most patients had a weak connection to the labor market and basic schooling. Patients were generally very motivated for treatment.

Further linking the data to Danish national register data makes it possible to follow individual trajectories pre- and post-admission as well as to access complete follow-up data regarding long-term outcomes, e.g., use of health services, mortality, morbidity, crime, and social circumstances. This article describes both the overarching aims of the REDD-PAC cohort and the basic diagnostic and sociodemographic characteristics of the cohort.