INTRODUCTION Insomnia and depression are highly prevalent disorders and commonly occur together. Cognitive behavioral therapy for insomnia, CBT-I, has been shown to be effective in treating insomnia and also comorbid depression. However, it is unclear whether effects of CBT-I on depression are specific or nonspecific. Also, depressive symptoms often remain too high after CBT-I, indicating a need for improved treatments. The objective was to determine whether combining CBT-I with CBT for depression, without increasing treatment length, reduces both insomnia and depression more than CBT for depression with a placebo insomnia intervention. METHODS A 12-week double-blind randomized controlled trial with a 6-month follow-up in a psychiatric setting using therapist-guided internet-delivered treatments was conducted. Patients (N = 126) were diagnosed with insomnia disorder and major depression by physicians. Primary outcome measures were as follows: self-rating scales Insomnia Severity Index (ISI) and Montgomery-Åsberg Depression Rating Scale (MADRS-S). RESULTS The combined treatment showed specific effects on insomnia severity over the control treatment (p = 0.007) but was not more effective in reducing depression severity. Within-group effects (Cohen's d) at post and at 6 months were as follows: ISI 1.40 and 1.42 (combined treatment), 0.95 and 1.00 (control); MADRS-S 0.97 and 1.12 (combined), 0.88 and 0.89 (control). CONCLUSIONS CBT-I shows large specific effects on insomnia severity and is superior to control in this regard. Both treatments had similar effects on depression severity, i.e., combining CBT-I with CBT for depression did not enhance outcomes on depression compared to control. We suggest CBT-I should always be offered to patients with insomnia and depression comorbidity, possibly as the first-hand choice. Combining it with a psychological treatment for depression could be too burdening and may not be beneficial.

中文翻译：

---

共病失眠和抑郁的心理治疗：双盲随机安慰剂对照试验。


简介 失眠和抑郁症是非常普遍的疾病，并且通常同时发生。失眠认知行为疗法 CBT-I 已被证明可以有效治疗失眠和共病抑郁症。然而，尚不清楚 CBT-I 对抑郁症的影响是特异性的还是非特异性的。此外，CBT-I 后抑郁症状通常仍然过高，表明需要改进治疗。目的是确定在不增加治疗时间的情况下，将 CBT-I 与 CBT 治疗抑郁症相结合，是否比 CBT 治疗抑郁症加安慰剂失眠干预更能减少失眠和抑郁。方法 在精神病学环境中进行了一项为期 12 周的双盲随机对照试验，并使用治疗师指导的互联网提供的治疗进行了 6 个月的随访。患者（N = 126）被医生诊断为失眠症和重度抑郁症。主要结果指标如下：失眠严重程度指数（ISI）自评量表和蒙哥马利-阿斯伯格抑郁量表（MADRS-S）。结果 与对照治疗相比，联合治疗对失眠严重程度显示出特定效果（p = 0.007），但在降低抑郁严重程度方面并没有更有效。术后和 6 个月时的组内效应 (Cohen's d) 如下：ISI 1.40 和 1.42（联合治疗）、0.95 和 1.00（对照）； MADRS-S 0.97 和 1.12（组合）、0.88 和 0.89（对照）。结论 CBT-I 对失眠严重程度显示出巨大的特异性影响，并且在这方面优于对照。两种治疗对抑郁症严重程度有相似的影响，即，与对照组相比，将 CBT-I 与 CBT 结合治疗抑郁症并没有改善抑郁症的结果。 我们建议始终向患有失眠和抑郁症合并症的患者提供 CBT-I，这可能是第一手选择。将其与抑郁症的心理治疗相结合可能会造成太大的负担，而且可能没有什么好处。