Table 1 Definitions of bipolar disorder according to the literature

Mason [12]

Spectrum that emphasizes two conditions: the lowest, melancholia; and the highest, mania

Koenders et al. [29]

BD is a chronic and highly disabling disease that is characterized by the constant risk of recurrence

Kerner [30]

Bipolar disorder is a complex genetic disorder; however, it has not been discovered how it is transmitted yet. Many investigators believe that common genomic variants present a risk of disease manifestation

APA [31]

It consists in one or more maniac or mixed episodes, with frequent presentation of one or more depressive episodes. If it is BAD I, there is at least one hypomania episode associated and, at least, one longer depressive episode, if it is BAD II

Meier et al. [32]

Severe psychiatric condition characterized by fundamental and distinctive distortions of emotion and perception regulation

Alvarez [33]

The BAD is characterized by humor alterations, alternating between maniac and depressive episodes, which can have different intensity and duration according to personal and situational characteristics

Lee [34]

Although there are still some disagreements regarding the clinical characteristics and doubts on which would be the cardinal symptoms of the disorder in children and adolescents, the world testified an amazing increase of BD incidence in this population during the last decade. Some studies suggest that the phenomenology of humor disorders can vary based on the cognitive functioning, social ability, and degree of psychological development of each subject

Department of Health and Human Services [35]

Disorder that causes non-usual alterations of humor and that can cause damage at school or even in interpersonal relationships

Abreu et al. [36]

Disorder that is strongly associated with suicidal ideation, suicide attempts, and suicide itself

Miasso [37]

Chronic disorder characterized by the existence of acute and recurrent episodes of humor pathological alteration

Costa [11]

Recurrent, chronic, and severe disease with significant impact on patients’ quality of life, and it is also a great burden to the family and society in general

OMS [38]

Disorder characterized by two or more episodes, in which the subject’s humor and level of activity are deeply disturbed. And such disturbance consists in some occasions of a humor rise and increase of energy and activity (hypomania or mania) and, in other times, a decrease of humor and energy and activity (depression)

Rocca and Lafer [39]

One of the most severe kinds of mental disease characterized by the presence of alternating episodes of humor (mania/hypomania and depression), which vary in intensity, duration, and frequency. Besides the classical episodes of mania, hypomania, and depression, mixed episodes, i.e., episodes with mania/hypomania phases and depression are also present

Vieira et al. [40]

The BHD is a severe, incurable, and cosmopolite disease. It is considered a complex disease that presents different clinical pictures and many neurobiological and etiological models that aim at explaining the appearance and manifestation of the disease

Moreno et al. [41]

Long-term, episodic, and potentially severe humor disorder that many times can have psychotic symptoms too. A continuous medical condition, for the entire lifecycle, with recurrent episodes that have great impact on the patient’s life, thus decreasing its functioning and quality of life