Troubles bipolaires du sujet âgé : pièges diagnostiques à éviter

Bipolar disorder involves several issues in clinical practice due to its underestimated incidence and its misleading appearance, especially due to the presence of sometimes impressive cognitive defects. Moreover, the classical etiological work-up for a late-onset depressive disorder or a state of a complex delirium where thymic symptoms predominate, one of the main issues is to analyze the mnemonic complaint with its cohort of cognitive defects within a history of depression, but also the issue of developing dementia in a patient with a psychiatric history. Many points thus remain to be clarified for a better featuring of these disorders. First: the clinical context must be carefully described by studying the other vulnerability factors of cognitive decline. Secondly: in a neuropsychological context, the duration, pattern and outcome of these disorders must be specified in order to identify differences with other types of dementia. Clinical examples illustrate the diagnostic differences with Alzheimer disease but above all with frontotemporal degeneration and Lewy bodies dementia. Through these clinical examples emerges a clinical and neuropsychological profile opening up new avenues for clinical and therapeutic research.