What is a key feature of Insomnia Disorder?

A key feature of Insomnia Disorder is the difficulty initiating or maintaining sleep. This condition is characterized by one or more of the following symptoms: trouble falling asleep, staying asleep, or waking up too early and not being able to return to sleep. These sleep disturbances can lead to significant distress or impairment in social, occupational, or other important areas of functioning.

The other options relate to different issues or disorders. For instance, excessive sleepiness during the day is more indicative of conditions such as hypersomnolence or narcolepsy. Involuntary bowel movements pertain to gastrointestinal disorders rather than sleep issues. Distress due to gender incongruence relates to gender dysphoria, which is also entirely separate from the symptoms and criteria defining insomnia. Thus, focusing on the specific difficulties with sleep initiation and maintenance helps to pinpoint Insomnia Disorder as defined in the DSM-5.