Homeless people and mental health: an observational study in an Emergency Shelter in Lisbon

Background
Lisbon municipality implemented several Emergency Shelters (Centros de Alojamento de Emergência Municipal – CAEM) to provide an answer to homeless people, namely following the COVID-19 pandemic. Such is the case of CAEM Sta Bárbara (CAEM-SB), an emergency shelter that opened on Sept 21, 2022.
The CAEM operates under the framework of a harm reduction intervention. Two NGOs manage the shelter (Ares do Pinhal and VITAE), sponsored and monitored by Lisbon Municipality. The available framework is supported by an interdisciplinary intervention in mental health., through screening and diagnosis, referral, and management in psychiatric community services Recently, mental health issues have become more evident among users, and a new research line has started. The present study reports on the preliminary analysis of a mental health screening performed at the CAEM-SB. It aims to provide the results of the intervention concerning healthcare resources utilization, and management of direct observation therapy (DOT), while providing insights on the link to hospital psychiatric appointments, treatment teams (ET), and therapeutic communities.  
Methods
All the users provided written signed informed consent forms and authorization namely to access epidemiological data and substance use records.
Results
Between January 2022 and December 2023, 491 people were monitored, of which 63% had monitoring in medication management -DOT-, and 87% had internal monitoring in General Medicine. Of these, 52% were linked to a psychiatry consultation, resulting in the following psychiatric diagnoses: Depression (34%), Anxiety (15%), Schizophrenia (14%), Bipolar Disorder (10%) and Cognitive Impairment (4%).
History of addictive behaviors and dependencies was identified in 88%, where 26% were linked to the mobile outreach program (MOP) and 18% were part of the medication protocol linked to the Lisbon Alcohol Unit (UAL), with 9% referred to ET. Of the people linked to ET and UAL, 20% joined the therapeutic community.
Conclusion
The landscape of the current homeless context in Lisbon shows increasing challenges. Addressing these challenges in a holistic approach and recognizing mental health issues in this population is essential to improve outcomes. 
The current harm reduction program and its positive outcomes in place at the CAEM provide a proof of concept for future initiatives in Portugal.