Shared clinical associations between obesity and impulsivity in rapid cycling bipolar disorder: a systematic review

Obesity seems to show a two-way relationship with bipolar disorder (BD), representing not only a possible vulnerability factor but also a consequence of chronic mood dysregulation associated with an overall poor prognosis. Increased impulsivity has been described across all stages and phases of BD as being also associated with a worse prognosis. Although obesity and impulsivity are common features among rapid cycling bipolar disorder (RC-BD) patients, there is a lack of understanding about the clinical implications of these conditions combined in BD.

To explore and integrate available evidence on shared clinical associations between obesity and impulsivity in RC-BD a systematic search of the literature in the electronic database of the National Library of Medicine (PubMed) has been conducted.

One hundred and fourteen articles were included in our systematic review. Among RC-BD patients, substance abuse disorders (SUDs), anxiety disorders (ADs), predominantly depressive polarity, chronic exposure to antidepressants, psychotic symptoms, suicidality, and comorbid medical conditions are strongly associated with both obesity and impulsivity.

Heterogeneity of published data, inconsistent measurements of both obesity and impulsivity in RC-BD and an absence of control for RC-BD in epidemiological surveys. Consequently, their combined impact on the severity of RC-BD is yet to be recognized and remains to be poorly understood.

In RC-BD patients the co-occurrence of obesity and impulsivity is associated with an unfavorable course of illness, specific shared clinical correlates, negative psychosocial impact, and overall worse prognosis. There is a need to examine obesity and impulsivity as modulating factors and markers of severity in RC-BD.