[Psychiatric symptoms of Lewy body dementia].

Lewy body dementia (LBD) is the second most common neurodegenerative disorder after Alzheimer's disease. Cognitive fluctuations, visual hallucinations, parkinsonian signs, and rapid eye movement sleep behavior disorder (RBD) are diagnostic criteria. However, the diverse clinical presentations complicate diagnosis and management, as the disease may begin with psychiatric symptoms, confusion, sleep disturbances, and/or autonomic dysfunction. Its progression often leads to neuropsychiatric and behavioral symptoms that can overshadow cognitive impairments. Diagnosing LBD is crucial to avoid first iatrogenic effects (e.g., neuroleptics), and then facilitate a personalized approach to address cognitive and neuropsychiatric management, while considering comorbidities.