Evidence shows that the prevalence and severity of mental disorders and the need for psychiatric admission is influenced by socio-demographic and contextual factors.

To characterize the severity of hospital admissions for psychiatric care due to common mental disorders and psychosis in Portugal.

This retrospective study analyses all acute psychiatric admissions for common mental disorders and psychosis in four Portuguese departments of psychiatry in the metropolitan areas of Lisbon and Porto, and investigates the association of their severity with socio-demographic and clinical factors.

Socio-demographic and clinical variables were obtained from the clinical charts of psychiatric admissions in 2002, 2007 and 2012 (n=2621). The number of hospital admissions per year (>1) and the length of hospital stay (31days) were defined as measures of hospital admission severity. Logistic regression analysis was used to assess which socio-demographic and clinical factors were associated with both hospital admission severity outcomes.

Results showed different predictors for each outcome. Being widowed, low level of education, being retired, having psychiatric co-morbidity, and a compulsory admission were statistically associated (P<0.05) with a higher number of hospital admissions. Being single or widowed, being retired, a diagnosis of psychosis, and a compulsory admission were associated with higher length of hospital stay, while having suicidal ideation was associated with a lower length of hospital stay.

Socio-demographic and clinical characteristics of the patients are determinants of hospital admissions for psychiatric care and of their severity.

Funding Fundação para a Ciência e Tecnologia (FCT), Portugal.