The presence of psychiatric comorbidity significantly impacts the quality of life for patients and often goes unnoticed within the realm of neurology.

This study’s objective was to elucidate and characterize psychiatric comorbidity among patients hospitalized for neurological disorders in mainland Portugal.

This retrospective observational study analyzed hospitalizations categorized with a primary diagnosis of neurological disorders, defined by Clinical Classification Software (CSS) for ICD-9-CM codes 76, 77, 79-85, 95, and 109, occurring in adult patients (≥18 years) between 2008 and 2015. Psychiatric comorbidity was determined by the presence of secondary diagnoses falling under CCS categories 650-670.

A total of 294,806 hospitalization episodes were documented with a primary diagnosis of neurological disorders in adult patients between 2008 and 2015 in Portuguese public hospitals. Approximately 26.9% (n=79,442) of these episodes were associated with documented psychiatric comorbidity (22.1% for female hospitalizations and 32.2% for male hospitalizations). Patients with recorded psychiatric comorbidity were younger (66.2±16.2 vs. 68.6±17.2 for those without psychiatric comorbidity, p<0.001), exhibited a lower overall in-hospital mortality rate, and experienced significantly longer mean hospital stays. Among these comorbidities, ‘Delirium, dementia, amnestic, and other cognitive disorders’ were documented in 7.4% (n=21,965) of hospitalizations, followed by alcohol-related disorders in 6.5% (n=19,302) and mood disorders in 6.1% (n=18,079). Epilepsy/seizures had the highest recorded psychiatric comorbidity rate among neurological disorders (39.9%).

Psychiatric comorbidity is present in more than a quarter of hospitalizations with a primary diagnosis of neurological disorders. The prevalence of psychiatric comorbidity varies across different neurological disorders and is associated with distinct demographic and clinical characteristics.

None Declared