Comparative study of effectiveness of cognitive-behavior therapy and zopiclone for chronic insomnia

Abstract

Chronic insomnia is a widespread and therapy resistant sleep disorder associated with multiple diseases and worsening of its course. Cognitive-behavior therapy of insomnia (CBT-I) is a pathogenetically based method of chronic insomnia treatment. 42 patients (male 14, female 28, age from 29 to 80) matched ICSD-3 criteria of chronic insomnia participated in the crossover study including 2-week courses of treatment by CBT-I and Zopiclone. All participants underwent polysomnography. Effectiveness of treatment was evaluated by questionnaires: Insomnia severity index (ISI), Pittsburgh sleep quality index, Beck depression inventory, Disfunctional beliefs about sleep, Sleep hygiene index. Treatment with CBT-I and zopiclone produced simular improvement of sleep quality with Insomnia severity index decreased to 3,6 (from 17,7±5,3 to 12,8±5,1) and 4,9 (from 16,5±5,8 to 12,9±6,2) respectively (р<0,05) while after two weeks of stopping treatment the significant difference remained only for CBT-I comparing with zopiclone treatment (12,9±6,2 and 15,5±4,6 points by ISI respectively) (p<0,05). The use of CBT-I leads to decrease of level of depression from 11,8±6,9 to 8,5±7, Sleep hygiene index decreases from 26,9±7,5 to 23,9±5,7 and disfunctional beliefs about sleep level drops from 104,9±29,7 to 84,4±34,2 (all these differences were significant at p<0,05). Analysis of the characteristics of responders and nonresponders has shown that the mean age of the first ones was younger comparing with nonresponders (40,5±12,9 and 57,2±11,7, p<0,05 respectively) that allows us to consider young age as predictor of CBT-I effectiveness. Treatment of chronic insomnia by CBT-I has simular efficacy as pharmacotherapy, but additionally it leads to the emprovement of emotional state and its therapeutistic effects after discontinuation lasts longer.