Supplementary Material for: Telephone-guided sleep restriction for insomnia: A randomized sleep diary-controlled trial

Introduction: Insomnia is common, but access to its first-line treatment, Cognitive Behavioral Therapy for Insomnia (CBT-I), is limited. To explore a scalable alternative, we investigated the efficacy of Sleep Restriction Therapy (SRT), a core component of CBT-I, delivered via telephone.
Methods: In a randomized controlled trial, 147 adults with insomnia were allocated to 6 weeks of telephone-guided SRT (n = 76) or a sleep diary control group (n = 71). The SRT group received weekly supporting phone calls lasting 10 to 15 minutes. At baseline and post-test, we measured insomnia severity (primary outcome), sleep diary measures, anxiety symptoms, depressive symptoms, pre-sleep arousal, sleep-safety behaviors, daytime sleepiness, and dysfunctional sleep-related cognitions (secondary outcomes). The SRT group repeated these measures at 3- and 6-month follow-up.
Results: Telephone-guided SRT showed large between-group effects on insomnia severity at post-test relative to the sleep diary control group (d = 1.52; p < .001). Based on intention-to-treat, 36 (47%) participants randomized to SRT achieved clinical improvement, and 23 (30%) achieved insomnia remission. We found medium-to-large between-group effects at post-test (d = 0.53 to 1.18) for all secondary outcomes except daytime sleepiness and total sleep time. At 3- and 6-month follow-up, the primary and all secondary outcomes, including daytime sleepiness and total sleep time, improved relative to baseline within the SRT group (d = 0.50 to 1.93).
Conclusion: This trial shows that telephone-guided SRT is an effective insomnia treatment requiring minimal therapist guidance. If direct comparisons with CBT-I corroborate these findings, SRT could be an interesting scalable alternative to CBT-I as a first-line insomnia treatment. Trial registry: NCT05548907

引言：失眠症具有较高的发病率，但其一线治疗方案——失眠认知行为疗法（Cognitive Behavioral Therapy for Insomnia, CBT-I）的可及性却较为有限。为探索可规模化推广的替代治疗方案，本研究针对失眠认知行为疗法的核心组分——睡眠限制疗法（Sleep Restriction Therapy, SRT），评估了其通过电话方式实施的临床疗效。
方法：本研究为一项随机对照试验，共纳入147名成年失眠患者，将其随机分为两组：电话指导睡眠限制疗法组（n=76）与睡眠日记对照组（n=71），两组干预周期均为6周。睡眠限制疗法组患者每周接受时长10至15分钟的支持性电话随访。于基线及干预结束时，本研究对以下指标进行评估：失眠严重程度（主要结局指标）、睡眠日记相关参数、焦虑症状、抑郁症状、睡眠前唤醒水平、睡眠安全行为、日间嗜睡程度以及功能失调性睡眠相关认知（次要结局指标）。此外，睡眠限制疗法组患者还在干预后3个月与6个月随访时重复完成上述指标的测评。
结果：相较于睡眠日记对照组，电话指导下的睡眠限制疗法在干预结束时对失眠严重程度展现出显著的组间大效应量（d=1.52；p<0.001）。基于意向性治疗分析，随机分配至睡眠限制疗法组的受试者中，共有36例（47%）实现临床症状改善，23例（30%）达到失眠临床缓解。除日间嗜睡程度与总睡眠时间外，其余所有次要结局指标在干预结束时均展现出中等至较大的组间效应量（d=0.53至1.18）。在干预后3个月与6个月随访时，睡眠限制疗法组的主要结局指标及所有次要结局指标（包括日间嗜睡程度与总睡眠时间）均较基线水平得到显著改善，效应量范围为0.50至1.93。
结论：本试验证实，电话指导下的睡眠限制疗法是一种仅需极少治疗师指导的高效失眠治疗手段。若后续与失眠认知行为疗法的直接对照研究能够验证本研究结果，则睡眠限制疗法有望成为失眠一线治疗中颇具应用前景的可规模化推广替代方案。试验注册编号：NCT05548907