Exams and Tests

Exams and tests may be done to rule out medical (eg, pain caused by arthritis or cancer) and psychiatric causes of insomnia.

The health care provider takes a thorough clinical interview with the person and his or her sleep partner regarding the person’s sleep habits.

The person may be asked to maintain a sleep diary. In this diary, the person describes the previous night’s sleep. Data from the sleep diary may help minimize distortions in sleep information recalled in the health care provider’s office.

Polysomnography (overnight sleep study test)

It is not recommended for the routine evaluation of sleeplessness but may be used in special circumstances (eg, to rule out causes of insomnia).

Psychophysiological insomnia and idiopathic insomnia manifest as increased sleep latency (taking a long time to fall asleep), reduced sleep efficiency, and increased number and duration of awakenings.

Sleep state misperception manifests as normal sleep latency (15-20 minutes), normal number of arousals and awakenings, and normal sleep duration (6.5 hours).

Idiopathic insomnia, previously called childhood-onset insomnia, is defined as a lifelong difficulty in initiating and maintaining sleep and resulting in poor daytime functioning. Psychophysiological insomnia is a chronic insomnia resulting from learned, sleep-preventing associations and increased tension or agitation. People with sleep state misperceptions report insomnia and sleeplessness but do not have objective evidence of a sleep disorder.

Multiple sleep latency test

In this test, the time taken by a person to fall asleep (sleep latency) during the day while lying in a quiet room is measured. In persons with sleep state misperception this test shows normal daytime vigilance. Vigilance in this sense means wakeful or alert state. The test shows that the person does not have increased or decreased sleep latency time (time required to fall asleep).

Sleep state misperception can only be diagnosed in the laboratory because of the need to document that sleep duration and quality are normal when a person describes having poor sleep.