Treatment of Specific Sleep Disorders

As noted above, both behavioral treatments and pharmacological treatments can be applied to the treatment of almost all sleep disorders. In this section, we describe how the general characteristics of these treatments, described above, are applied to specific sleep disorders.

Primary Sleep Disorders: Dyssomnias

Primary Insomnia
Primary insomnia is a condition involving difficulty initiating or maintaining sleep, or nonrestorative sleep, for at least 1 month. The sleep disturbance (or associated daytime fatigue) must cause significant distress or impairment in social or occupational functioning. In primary insomnia, the sleep disturbance is not due to an underlying mental disorder (e.g., major depression), medical illness (e.g., congestive heart failure), substance abuse disorder, or another sleep disorder (e.g., sleep apnea).

In treatment outcome research, the definition of insomnia is often more operational and typically refers to a latency to sleep onset and/or time awake after sleep onset greater than 30 minutes per night, with a corresponding sleep efficiency of less than 85%, on 3 or more nights per week for at least 6 months.

Several subtypes of primary insomnia have been described. These include psychophysiological insomnia, a conditioned sleep problem that results from learned sleep-preventing associations and somatized tension; idiopathic insomnia, a lifelong inability to obtain adequate sleep, which may represent a defect in neuronal sleep/wake mechanisms; and sleep state misperception, a gross discrepancy between subjective and objective sleep measurements. To date, distinctions among these subtypes have not been strongly supported by empirical research, and many patients with chronic insomnia have some evidence for each subtype (Edinger et al. 1996; Reynolds et al. 1991).

Behavioral/psychotherapeutic treatment Insomnia has received more research attention than any other sleep disorder. The findings of more than 50 treatment studies (involving more than 2,000 patients) of nonpharmacological interventions for insomnia have been summarized in two separate meta-analyses (Morin et al. 1994a; Murtagh and Greenwood 1995) and in a recent practice parameter paper by a task force of the American Academy of Sleep Medicine (Morin et al. 1999b). The data indicate that behavioral treatment (lasting an average of 4-6 weeks) produces reliable and durable changes in several sleep parameters of patients with chronic insomnia. For example, sleep-onset latency is reduced from an average of 60-65 minutes at baseline to about 35 minutes at posttreatment. The duration of awakenings is similarly decreased, from an average of 70 minutes at baseline to about 38 minutes following treatment. Total sleep time is increased by a modest 30 minutes, from 6 hours at baseline to 6 hours after treatment, but perceived sleep quality is significantly enhanced with treatment. Overall, between 70% and 80% of patients benefit from treatment, about one-third become good sleepers, and a small proportion do not benefit from treatment. Sleep improvements achieved with behavioral interventions are well sustained over time, with follow-up evaluations averaging 6 months after treatment completion.