Abstract
PURPOSE OF REVIEW: This paper explores Predominant Polarity (PP) in Bipolar Disorder (BD), defined as the predominance of either manic or depressive episodes over a patient's course of illness. We examine its clinical relevance, neurobiological foundations, and potential for guiding personalized treatment strategies. The review seeks to determine whether PP is a reliable course specifier and how it can be utilized to improve clinical outcomes. RECENT FINDINGS: PP has a significant impact on prognosis and treatment planning in BD. Manic and depressive PP are associated with distinct clinical and neurobiological profiles of BD, while individuals without a clear predominance of either episode type represent a more severe to-treat subgroup of patients. The development of the Polarity Index (PI) facilitates treatment decisions based on PP. PP offers a valuable framework for refining BD treatment and understanding its complexity. Future research should focus on refining PP definitions, validating neurobiological markers, and integrating these insights into comprehensive treatment models to improve patient outcomes.