【正确答案】正确答案： Insomnia is more than just being unable to fall asleep. It is a subjective condition of insufficient or nonrestorative sleep despite an adequate opportunity to sleep. Insomnia represents a symptom of an underlying problem and is not in itself a disease entity. A consensus seems to support dividing insomnia into transient, short-term, and long-term or chronic. A pertinent history for insomnia would include: 1. Restlessness, irritability, daytime somnolence, can leads to difficulties with initiation of sleep and early awakenings. 2. Use of caffeine or other stimulants. Late evening exercise can also be a stimulant. 3. Affect changes, sadness, hopelessness, and vegetative signs such as weight loss should suggest depression, the most common psychiatric disorder associated with insomnia. 4. some medical problems have been implicated in insomnia. 5. Loud snoring, daytime somnolence, forgetfulness, difficulty concentrating, and a history from the bed partner of periods of discontinuation of breathing during sleep of 10 seconds or more should suggest a more thorough evaluation for obstructive sleep apnea. The key to diagnosing insomnia and other sleep disorders is history and sleep laboratory monitoring. Short-term problems related to difficulty with initiating sleep may be situational or environmental. Long-term problems with sleep may be more psychophysiologic. A good sleep study often confirms the diagnosis and leads to specific interventions.