Late‐life mood disorder as the initial presentation of progressive supranuclear palsy: A case series

Progressive supranuclear palsy (PSP) is a rapidly progressive neurodegenerative disorder characterized by Parkinsonism, supranuclear ophthalmoplegia, postural instability, and cognitive impairment.This case series describes three patients initially diagnosed with late‐life mood disorders (depression and bipolar disorder) who were later diagnosed with PSP because of the development of typical neurological symptoms.The diagnostic challenge of PSP is highlighted in this case report, particularly in the early stages, when characteristic symptoms may not be present. The importance of considering PSP in the differential diagnosis of late‐life mood disorders, especially in the absence of response to standard antidepressant therapy, is also emphasized. The heterogeneity of PSP is described, with various subtypes and atypical variants presenting with different clinical features. The psychiatric symptoms of PSP include apathy, disinhibition, depression, and anxiety, whereas hallucinations and delusions are less frequent. Tau positron emission tomography imaging is discussed as a potential biomarker for atypical PSP.Early diagnosis and intervention are crucial for improved outcomes in PSP, necessitating further research to enhance the diagnostic and treatment strategies for PSP and other neurodegenerative diseases.