BACKGROUND: Persistent primary insomnia is common (affecting up to 5% of the general population) and predicts both depression and increased health care use. Common treatments include sedative hypnotics and antidepressants, both of which have numerous side effects and often lead to a relapse once they are stopped. Behavioral treatments have shown more durable improvements but only address sleep onset problems. It is not known whether CBT, by addressing both sleep onset and sleep maintenance problems, can provide a better outcome.
POPULATION STUDIED: The study included 75 adults (aged 40-80 years) with a mean duration of symptoms of 14 years who were recruited by a single academic medical center primarily through newspaper ads. Multiple exclusion criteria included anyone meeting criteria for an Axis I psychiatric disorder (including major depression).
STUDY DESIGN AND VALIDITY: Patients were randomly assigned (uncertain allocation concealment) to a therapist offering CBT, relaxation training (RT), or placebo treatment (PT) on a weekly basis for 6 weeks (3-6 hours of total contact). Those in the CBT arm were educated to misconceptions about sleep requirements and the effects of aging, circadian rhythms, and sleep loss on sleep/wake functioning, followed by instructions to: (1) establish a standard wake-up time; (2) get out of bed during extended awakenings; (3) avoid sleep-incompatible behaviors in bed; and (4) eliminate daytime napping. They also received sleep prescriptions with weekly adjustments based on sleep efficiency. RT recipients received progressive muscle relaxation training and were encouraged to use these skills to help return to sleep on awakening. PT recipients received “quasi-desensitization treatment” involving imagined scenes of neutral activities to eliminate conditioned arousals. The subjects completed pretreatment assessment, 6 weeks of therapy, 2 weeks of post-treatment assessment, and a 6-month follow-up assessment.
OUTCOME MEASURED: The outcomes measured included objective (polysomnography) and subjective (sleep logs) evaluations of total sleep time, wake time after sleep onset (WASO), and sleep efficiency. Questionnaires were used to assess subjective insomnia symptoms, changes in perceived control over sleep, and mood disturbances.
RESULTS: Overall, CBT was superior to both RT and PT in treating chronic insomnia. CBT recipients reported a 54% reduction in WASO compared with 16% and 12% for RT and PT patients, respectively (P=.02). CBT also produced greater improvements in sleep efficiency and improved subjective insomnia symptoms. An objective increase in total sleep time measured by polysomnography in the CBT group (approximately 12 minutes) persisted through the 6-month follow-up period. The PT group showed a decrease in objective sleep time (approximately 9 minutes). Objective (polysomnographic) differences were less dramatic than those derived from the sleep log, although both favored CBT.
CBT is an effective method for treating chronic insomnia. Given the cost, side effects, and temporary benefits of pharmacologic interventions, these CBT methods deserve consideration as first-line therapy for chronic insomnia. Although chronic insomnia is predictive of depression and increased medical use, these endpoints were not specifically addressed. Since those patients were excluded, using CBT to improve insomnia in depressed patients may not be appropriate. Symptoms that might be a consequence of insomnia, such as daytime fatigue and poor job performance, were not studied. Although improvement of these symptoms with increased sleep might be expected, this remains to be proved.