Cognitive impairment in bipolar disorder Neuroprogression or behavioral variant frontotemporal dementia?

Patients with Bipolar Disorder (BD) usually display cognitive deficits with aging. However, the correlation between BD and dementia syndromes is inconclusive, despite the similarity with behavioral variant frontotemporal dementia. We report a 78-year-old female patient who had bipolar type 1 disorder since adolescence. Her symptoms ranged from apathy to psychotic mania. She had had three hospitalizations, and since her last stay 10 years ago, her symptoms had remained stable. However, in the past 2 years, she displayed different symptoms, such as irritability manifested as verbal and physical aggression, cognitive impairment, repetitive pattern of behavior, perambulation, persecutory delusions, disorientation, and hyporexia. Treatment with anticholinesterases or mood stabilizers promoted no improvement. She scored 17/30 points on the Mini-Mental State Examination. Neuropsychological assessment suggested deficits in executive function, attention, and memory. Neuroimaging tests revealed frontotemporal degeneration and hypoperfusion. Diagnostic and therapeutic approaches for this type of patient represent a significant challenge for clinicians.