Bipolar disorder.

The hallmark of bipolar disorder is hypomania or mania, and the predominant phase of illness is depression. Affecting approximately 40 million individuals worldwide, bipolar disorder is associated with a substantial psychosocial, medical, and financial burden and increased mortality from suicide and other causes. Diagnosis can be challenging due to symptom overlap with attention-deficit hyperactivity disorder, major depressive disorder, psychotic spectrum disorders, and personality disorders, which often leads to a delay in diagnosis. Recent advancements in understanding disease risk and pathophysiology have identified multigene risk and possible infectious and mitochondrial causes. Treatment approaches include pharmacotherapy, psychotherapy, and lifestyle modifications, which should always be patient-centred and aligned with individual goals and priorities. Future directions for bipolar disorder care include increasing the availability of psychosocial interventions aimed at self-management, addressing treatment-resistant bipolar depression, deepening the understanding of pathophysiology, and exploring novel interventions, such as ketamine, esketamine, other rapid-acting antidepressants, and various neuromodulation approaches.