Schizophrenia Related Hospitalizations - a Big Data Analysis of a National Hospitalization Database.

Schizophrenia is a mental disorder characterized by long hospitalizations and frequent need for chronic/acute psychiatric care. Hospitalizations represent a valuable quality of care indicator in schizophrenia patients. The aim of this study was to describe a nationwide perspective of schizophrenia related hospitalizations. We performed a retrospective observational study using a nationwide hospitalization database containing all hospitalizations registered in Portuguese public hospitals from 2008 to 2015. Hospitalizations with a primary diagnosis of schizophrenia were selected based on the definition by CCS - Clinical Classification Software diagnostic single-level 659. Schizophrenia subtypes were identified based on International Classification of Diseases version 9, Clinical Modification (ICD-9-CM) codes of diagnosis 295.xx. A total of 25,385 hospitalizations were registered belonging to 14,279 patients. 68.0% of the hospitalizations occurred in male patients and the median length of stay was 18.0 days. In male patients' hospitalizations, the most frequent age group was 31-50 years followed by the age group of 18-30 years (55.9 and 24.0% respectively). For female patients, the most frequent age group was 31-50 years followed by 51-70 years (54.1 and 22.6%, respectively). There were 73 hospitalization with a deadly outcome (0.29%). Paranoid type was the most frequent subtype of schizophrenia (50.5%). The mean hospitalization charges were 3509.7€ per episode, with a total charge of 89.1 M€ in the 8-year period. This is a nationwide study using Big Data analysis giving a broad perspective of schizophrenia hospitalization panorama at a nationwide level. We found differences in hospitalization characteristics according to patients' gender, age and primary diagnosis.