Which of the following is a common sign of depression in bipolar disorder?

Sleep disturbance is a common sign of depression in bipolar disorder. Individuals experiencing a depressive episode may struggle with insomnia, hypersomnia, or altered sleep patterns, which can significantly impact their daily functioning and overall well-being. These disturbances occur because the depressive phase is associated with feelings of sadness, hopelessness, and a lack of energy, often leading to difficulties in maintaining a regular sleep schedule.

In bipolar disorder, the mood fluctuations between depressive episodes and manic or hypomanic episodes can cause various symptoms. While joyful moods and euphoria are characteristic of the manic state, they do not pertain to the depressive phase. Increased energy is also associated with mania rather than depression. Therefore, sleep disturbances serve as a critical indicator of the depressive aspect of bipolar disorder, helping healthcare providers identify and manage the condition more effectively.