Effect of trazodone versus cognitive‐behavioural treatment on high‐ and slow‐frequency activity during non‐rapid eye movement sleep in chronic insomnia: A pilot, randomized clinical trial

Trazodone and cognitive-behavioural treatment for insomnia (CBT-I) are widely used to treat patients with chronic insomnia. Although both treatments improve sleep continuity, no study has compared their comparative effectiveness in modifying spectral electroencephalographic (EEG) activity during sleep in humans. In this study, participants included 19 men and women with chronic insomnia who were randomized to either trazodone (n = 8) or CBT-I (n = 11) treatment for 3 months. We examined delta (0.39-3.91 Hz), theta (4.30-7.81 Hz), alpha (8.20-11.72 Hz), sigma (12.11-14.84 Hz), beta (15.23-35.16 Hz) and gamma (35.55-49.61 Hz) relative power during non-rapid eye movement (NREM) sleep at pre-treatment, 3- month post-treatment and 6-month follow-up. This study was registered in Clinical Trials (NCT01348542). We found trazodone but not CBT-I significantly decreased sigma (p = .041, d = 0.88; time × group p = .009) and beta (p = .005, d = 1.41; time × group p = .016) power during NREM sleep at post-treatment. Compared to CBT-I, trazodone increased delta (p = .018) and decreased sigma (p = .013) and beta (p = .023) power during NREM sleep at post-treatment. At follow-up, we did not observe significant changes in relative EEG power during NREM sleep in either the CBT-I or trazodone group compared to pre-treatment. Compared to CBT-I, trazodone decreased alpha (p = .039) and sigma (p = .009) power during NREM sleep at follow-up. In conclusion, trazodone, but not CBT-I, decreased fast-frequency EEG activity during NREM sleep. Compared to CBT-I, trazodone appears to have a stronger impact on cortical and physiological hyperarousal in patients with chronic insomnia.