Huntington's Disease and Psychiatric Comorbidities: A Retrospective Study in Portugal

Huntington's disease is a progressive neurodegenerative disorder characterized by motor, cognitive, and behavioral symptoms. While psychiatric comorbidity is common and may influence disease outcomes, there is a lack of data on its prevalence and impact in Portugal. This study aimed to analyze the frequency and impact of a diagnosis of psychiatric comorbidities among Huntington's disease hospitalized patients in Portugal.

A retrospective observational study was conducted using administrative data from Portuguese public hospitals within the National Health Service between 2000 and 2016. All hospitalization episodes of patients with a diagnosis of Huntington's disease (International Classification of Diseases, Ninth Revision, Clinical Modification code 333.4) were analyzed. Comorbid psychiatric diagnoses registered as primary or secondary diagnoses were identified and defined using the Clinical Classification Software codes 650-670. Age at admission, length of hospital stay, admission type, in-hospital mortality, and estimated hospital charges were analyzed according to psychiatric comorbidity categories and adjusting for age and sex.

A total of 1667 hospitalizations with a diagnosis of Huntington's disease occurred between 2000 and 2016, of which 28.97% had a psychiatric comorbidity. These patients were more likely to be younger (adjusted odds ratio = 1.32, 95% confidence interval 1.07 - 1.64; p = 0.011) and to have longer hospitalizations (adjusted odds ratio = 1.88, 95% confidence interval 1.52 - 2.34; p < 0.001) than those with no psychiatric comorbidity. No association was found between psychiatric comorbidity in general and in-hospital mortality, admission type or hospitalization costs. An upward trend was observed in Huntington's disease admissions and the percentage of those with psychiatric comorbidity over the study period.

Psychiatric comorbidity in Huntington's disease was associated with younger age at admission and longer hospitalizations. These results highlight the importance of psychiatric care in the management of these patients. Early screening and intervention could improve outcomes and optimize healthcare resource allocation.