A growing international scientific literature demonstrates the existence of sleep abnormalities and sleep/wake (or circadian) rhythms in bipolar disorder. These abnormalities exist during the acute phases of the disease, with the classic presentation of insomnia or hypersomnia during depressive episodes and a reduced need for sleep without feeling tired during manic episodes. But these disturbances can also appear or persist during phases of mood stability. However, it has now been clearly demonstrated that these disturbances can precipitate a new depressive or manic episode.

Anxiety disorders are among the main comorbidities encountered in patients with bipolar disease. Numerous clinical and epidemiological studies show an increased prevalence of anxiety pathologies (generalized anxiety disorder, social anxiety disorder, obsessive-compulsive disorder, panic disorder, and post-traumatic stress disorder) in bipolar subjects compared to the frequencies in the general population. Anxiety disorders are not without consequences on the evolutionary course of the mood disorder, including a significant reduction in euthymia time and less sensitivity to conventional medicinal therapies.

Bipolar disorder is a chronic illness, defined by a succession of depressive and/or manic periods separated by free intervals. Its evolution with aging is marked by a high suicide mortality rate. Bipolar disorders raise the question of their evolution when the age of the subject, in particular with regard to their frequency, their clinical characteristics, their prognosis and their management. The evolution of bipolar disorder with aging poses several difficulties in clinical practice due to its underestimated frequency and its misleading presentation and in particular by the presence of sometimes significant cognitive alterations leading sometimes to dementia.