Approximately 1-10% of the general adult population suffers with recurrent problems with either falling asleep or being able to stay asleep through the night. The incidence of insomnia in the elderly increases to as much as 25%. The course of primary insomnia is variable. It may last as little as a few months. However, according to the DSM-IV TR, 50-75% of individuals with insomnia complaints have chronic symptoms lasting for more than one year. and previous insomnia is the strongest single risk factor for current insomnia. The diagnostic criteria for primary insomnia, according to the DSM-IV TR are as follows:

Criteria A: The predominant complaint is difficulty initiating or maintaining sleep or nonrestorative sleep for at least one month.

Criteria B: Sleep disturbance (or associated daytime fatigue) causes clinically significant distress or impairment in social, occupational, or other important areas of functioning.

Criteria C: The sleep disturbance does not occur exclusively during the course of narcolepsy, breathing-related sleep disorders, circadian rhythm sleep disorder, or parasomnia.

Criteria D: The disturbance does not occur exclusively during the course of another mental disorder (for example, major depressive disorder, generalized anxiety disorder, delirium).

Criteria E: The disturbance is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition.

Community Clinical Research frequently is involved in conducting trials of investigational medications for the treatment of primary insomnia.