EPP154 - Psychiatric Morbidity and Mortality-Survival Among Homeless People: Evidence from a Two-Decade Portuguese 333 Patient Cohort

EPP154

Psychiatric Morbidity and Mortality-Survival Among Homeless People: Evidence from a Two-Decade Portuguese 333 Patient Cohort

J. Gama-Marques¹²³, J. Henriques-Calado^3,*

¹Consulta de Esquizofrenia Resistente, Hospital Júlio de Matos, Unidade Local de Saúde São José, Centro Clínico Académico de Lisboa, Lisboa, Portugal, ²Clínica Universitária de Psiquiatria e Psicologia Médica, Faculdade de Medicina, Universidade de Lisboa, Centro Académico de Medicina de Lisboa, Lisboa, Portugal, ³Centro de Investigação em Ciência Psicológica (CICPSI), Faculdade de Psicologia, Universidade de Lisboa, Lisboa, Portugal

Introduction: Homelessness represents a critical determinant of mental disorders, closely linked to psychiatric morbidity, substance use, and premature mortality. However, longitudinal evidence on homeless psychiatric populations in Southern Europe is still limited.

Objectives: This study aimed to characterize the socio-demographic, clinical, and mortality/survival outcomes of homeless psychiatric patients, with an emphasis on diagnostic patterns associations over a 20-year follow-up.

Methods: A retrospective analysis was conducted on 333 homeless psychiatric patients monitored over two decades, based on electronic clinical records. Data included socio-demographic information, ICD-10 psychiatric diagnoses at baseline and last contact, lifetime comorbidities, utilization of psychiatric services, and mortality outcomes. Mortality distribution and diagnostic associations were examined using descriptive, cox regression, and inferential analyses.

Results: The cohort was predominantly male (87.7%), with a mean age of 47 years at baseline and 56 years at final contact. Mean psychiatric follow-up extended for nine years, with limited-service utilization (M=1.5 hospitalizations; M=51 inpatient days). Overall mortality reached 31.2%, with a mean age at death of 61 years, considerably lower than national life expectancy. Alcohol abuse was present in 57.7% of deceased patients. Diagnoses most strongly associated with mortality included alcohol-related disorders (ICD-10 F10; χ²=20.53, p<.001), organic psychosis (ICD-10 F06; χ²=14.38, p<.001), and unspecified psychosis (ICD-10 F29; χ²=8.47, p<.05). Intellectual disability (χ²=9.36, p<.01) and comorbid substance use were also significant predictors. Survival analyses highlighted alcohol use disorders and organic psychosis as major negative prognostic factors, whereas patients with long-standing psychosis and intellectual disability demonstrated greater variability in survival outcomes.

Conclusions: This 20-year study reveals a substantial mortality burden among homeless psychiatric patients, strongly linked to alcohol-related disorders and organic psychosis. The findings underscore the critical need for integrated and diagnosis-specific interventions to mitigate premature mortality in this vulnerable homeless psychiatric population.

Disclosure of Interest: None Declared