Sleep Restriction Therapy For Insomnia Research Articles

P058 Dissecting Sleep Restriction: Defining and Empirically testing a two-stage Build-Maintain model of Sleep Restriction Therapy for Insomnia

Abstract Introduction Sleep Restriction Therapy (SRT) is one of the core components of CBT for Insomnia (CBT-I). However, there is little empirical evidence regarding how SRT implementation evolves over the course of therapy. Here, we propose a conceptual model for defining stages of SRT and assess the applicability of the model in a recently completed clinical trial. Methods Our proposed two-stage Build-Maintain model of SRT is: 1) The Build stage starts with SRT implementation. The primary goal is building homeostatic pressure until average weekly sleep efficiency (SE) is high enough to increase time-in-bed (e.g., 85% or 90%). 2) The Maintain stage starts with the first increase of time-in-bed after the target SE is reached. The goal is to maintain sleep pressure sufficiently high that one can maintain SE in the desired range. We assessed the model in 83 adults (age=48.3±14.8 years; 50F) undergoing CBT-I in a RCT. SRT was introduced in week 2. We explored the extent to which age, sex, psychiatric comorbidities, use of hypnotics, and baseline insomnia severity predicted progression through the SRT stages. Results Participants were in the Build stage 2.1±1.3 weeks (41.8% were in Build for only one week; 84% for ≤3 weeks). Higher baseline ISI (r=.238,p=.036) and lower baseline SE (r=-.365,p=.001) predicted spending more weeks in the Build stage before transitioning to the Maintain stage. Discussion The two-stage Build-Maintain model of SRT may inform: a) setting empirically-based expectations for client progress; b) examining adherence to CBT-I; c) evaluating shortened versions of CBT-I.

Clinical and cost-effectiveness of nurse-delivered sleep restriction therapy for insomnia in primary care (HABIT): a pragmatic, superiority, open-label, randomised controlled trial

Insomnia is prevalent and distressing but access to the first-line treatment, cognitive behavioural therapy (CBT), is extremely limited. We aimed to assess the clinical and cost-effectiveness of sleep restriction therapy, a key component of CBT, which has the potential to be widely implemented. We did a pragmatic, superiority, open-label, randomised controlled trial of sleep restriction therapy versus sleep hygiene. Adults with insomnia disorder were recruited from 35 general practices across England and randomly assigned (1:1) using a web-based randomisation programme to either four sessions of nurse-delivered sleep restriction therapy plus a sleep hygiene booklet or a sleep hygiene booklet only. There was no restriction on usual care for either group. Outcomes were assessed at 3 months, 6 months, and 12 months. The primary endpoint was self-reported insomnia severity at 6 months measured with the insomnia severity index (ISI). The primary analysis included participants according to their allocated group and who contributed at least one outcome measurement. Cost-effectiveness was evaluated from the UK National Health Service and personal social services perspective and expressed in terms of incremental cost per quality-adjusted life year (QALY) gained. The trial was prospectively registered (ISRCTN42499563). Between Aug 29, 2018, and March 23, 2020 we randomly assigned 642 participants to sleep restriction therapy (n=321) or sleep hygiene (n=321). Mean age was 55·4 years (range 19-88), with 489 (76·2%) participants being female and 153 (23·8%) being male. 580 (90·3%) participants provided data for at least one outcome measurement. At 6 months, mean ISI score was 10·9 (SD 5·5) for sleep restriction therapy and 13·9 (5·2) for sleep hygiene (adjusted mean difference -3·05, 95% CI -3·83 to -2·28; p<0·0001; Cohen's d -0·74), indicating that participants in the sleep restriction therapy group reported lower insomnia severity than the sleep hygiene group. The incremental cost per QALY gained was £2076, giving a 95·3% probability that treatment was cost-effective at a cost-effectiveness threshold of £20 000. Eight participants in each group had serious adverse events, none of which were judged to be related to intervention. Brief nurse-delivered sleep restriction therapy in primary care reduces insomnia symptoms, is likely to be cost-effective, and has the potential to be widely implemented as a first-line treatment for insomnia disorder. The National Institute for Health and Care Research Health Technology Assessment Programme.

The effect of sleep restriction therapy for insomnia on sleep pressure and arousal: a randomized controlled mechanistic trial.

Sleep restriction therapy (SRT) effectively treats insomnia but mechanisms are poorly understood. Theoretical models suggest that potentiation of sleep pressure and reduction of arousal are key mechanisms of action. To our knowledge, this has never been directly tested. We designed a randomized controlled trial with embedded mechanistic measurement to investigate if SRT causally modifies multidimensional assessments of sleep pressure and arousal. Participants aged 25-55 who met DSM-5 diagnostic criteria for insomnia disorder were randomized to four weeks of SRT or time in bed regularization (TBR), a control intervention that involves prescription of a regular but not reduced time in bed. Sleep pressure was assessed through daily diary appraisal of morning and evening sleepiness, weekly Epworth sleepiness scale (ESS) scores, psychomotor vigilance, and non-rapid eye movement (NREM) delta power (0.75-4.5 Hz) from ambulatory polysomnographic recordings. Arousal was assessed through daily diary appraisal of cognitive arousal, the pre-sleep arousal scale (PSAS), and NREM beta power (15-32 Hz). Outcomes were assessed at baseline (2-week period prior to randomization), during the intervention phase (1-4 weeks post-randomization), and at 12-week follow-up. We performed intention-to-treat analyses using linear mixed models. For continuous daily measures, the treatment period was split into early (weeks 1-2) and late (weeks 3-4) treatment. Fifty-six participants (39 females, mean age = 40.78 ± 9.08) were assigned to SRT (n = 27) or TBR (n = 29). The SRT group showed enhanced sleep pressure relative to TBR, reflected in (1) enhanced sleepiness in the evening during early (d = 1.17) and late treatment (d = 0.92), and in the morning during early treatment (d = 0.47); (2) higher daytime sleepiness on the ESS at weeks-1 and -2 (d = 0.54, d = 0.45); and (3) reduced psychomotor vigilance at week-1 (d = 0.34). The SRT group also showed reduced arousal relative to TBR, reflected in lower levels of daily-monitored cognitive arousal during early treatment (d = 0.53) and decreased PSAS total score at week-4 and week-12 (ds ≥ 0.39). Power spectral analysis of all night NREM sleep revealed an increase in relative, but not absolute, EEG delta power at week-1 and week-4 (ds ≥ 0.52) and a decrease of relative EEG beta power at week-4 (d = 0.11). For the first time, we show that SRT increases sleep pressure and decreases arousal during acute implementation, providing support for mechanism-of-action.

The acute effects of sleep restriction therapy for insomnia on circadian timing and vigilance.

Sleep-restriction therapy (SRT) has been shown to improve insomnia symptoms by restricting sleep opportunity. Curtailment of time in bed affects the duration and consolidation of sleep, but also its timing. While recent work suggests that people with insomnia are characterised by misalignment between circadian and behavioural timing of sleep, no study has investigated if SRT modifies this relationship. The primary aim of the present study was to examine change in phase angle after 2weeks of SRT. As a secondary aim, we also sought to assess the effect of SRT on psychomotor vigilance. Following a 1-week baseline phase, participants implemented SRT for 2 consecutive weeks. Phase angle was derived from the difference between the decimal clock time of dim light melatonin onset (DLMO) and attempted sleep time. Secondary outcomes included vigilance (assessed via hourly measurement during the DLMO laboratory protocol), sleep continuity (assessed via sleep diary and actigraphy), and insomnia severity. Eighteen participants meeting insomnia criteria (mean [SD] age 37.06[8.99]years) took part in the study. Consistent with previous research, participants showed robust improvements in subjective and objective sleep continuity, as well as reductions in insomnia severity. The primary outcome (phase angle) was measurable in 15 participants and revealed an increase of 34.8min (~0.58hr; 95% confidence interval [CI] 0.01-1.15) from baseline to post-treatment (mean [SD] 2.27[0.94] versus 2.85[1.25]hr). DLMO remained relatively stable (20:49 versus 21:01hours), while attempted sleep was 46.8min later (~0.78hr; 95%CI 0.41-1.15; 23:05 versus 23:52hours). For psychomotor vigilance, reaction time was delayed (by 52.71ms, 95% CI 34.44-70.97) and number of lapses increased (by 5.84, 95% CI 3.93-7.75) after SRT. We show that SRT increases phase angle during treatment, principally by delaying the timing of sleep attempt. Future studies are needed to test if an increase in phase angle is linked to clinical improvement. Finally, reduction in vigilance after SRT appears to be of similar magnitude to normal sleepers undergoing experimental sleep restriction, reinforcing the importance of appropriate safety advice during implementation.

Is restriction of time in bed central to the efficacy of sleep restriction therapy for insomnia? results from a randomised, controlled, dismantling trial comparing sleep restriction with bedtime consistency

Is restriction of time in bed central to the efficacy of sleep restriction therapy for insomnia? results from a randomised, controlled, dismantling trial comparing sleep restriction with bedtime consistency

0385 Daytime Impairment during Sleep Restriction Therapy for Insomnia: Results from a Randomised-Controlled Trial

0385 Daytime Impairment during Sleep Restriction Therapy for Insomnia: Results from a Randomised-Controlled Trial

A Drosophila model of sleep restriction therapy for insomnia.

Insomnia is the most common sleep disorder among adults, especially affecting individuals of advanced age or with neurodegenerative disease. Insomnia is also a common comorbidity across psychiatric disorders. Cognitive Behavioral Therapy for Insomnia (CBT-I) is the first-line treatment for insomnia; a key component of this intervention is restriction of sleep opportunity, which optimizes matching of sleep ability and opportunity, leading to enhanced sleep drive. Despite the well-documented efficacy of CBT-I, little is known regarding how CBT-I works at a cellular and molecular level to improve sleep, due in large part to an absence of experimentally-tractable animals models of this intervention. Here, guided by human behavioral sleep therapies, we developed a Drosophila model for Sleep Restriction Therapy (SRT) of insomnia. We demonstrate that restriction of sleep opportunity through manipulation of environmental cues improves sleep efficiency in multiple short-sleeping Drosophila mutants. The response to sleep opportunity restriction requires ongoing environmental inputs, but is independent of the molecular circadian clock. We apply this sleep opportunity restriction paradigm to aging and Alzheimer’s Disease fly models, and find that sleep impairments in these models are reversible with sleep restriction, with associated improvement in reproductive fitness and extended lifespan. This work establishes a model to investigate the neurobiological basis of CBT-I, and provides a platform that can be exploited towards novel treatment targets for insomnia.

Polysomnographical effects of on-line sleep restriction therapy for insomnia

Polysomnographical effects of on-line sleep restriction therapy for insomnia

Exploring a Behavioural Therapy for Insomnia in Shift Workers

About 30% of Canadian workers are on shift work schedules, and 8% to 32% of them suffer from Shift Work Disorder (SWD). Only a few behavioural treatments exist to treat this population. This study explores the efficacy and feasibility of sleep restriction therapy for insomnia in a group of night shift workers. Six participants (3 women) meeting SWD criteria were recruited. Mean age was 45.7 years old (SD=8.2). A multiple baseline design was used. After baseline, each participant received six to eight weekly treatment sessions. They completed several selfreported questionnaires and a daily sleep diary throughout the study. For each sleep period, sleep variables were calculated from the sleep diary. Two participants had a high treatment response and all others participants had a moderate response. Moreover, all participants presented at least two significant clinical improvements. Five participants presented a decreased in both sleepiness scores. The study suggests that sleep restriction therapy is effective, feasible, and reliable. Sleep restriction therapy for insomnia could improve sleep and diminish sleepiness in shift workers suffering from SWD. The present study opens new possibilities of treatment for shift workers that deserve greater attention in the future.

Ecological momentary assessment of daytime symptoms during sleep restriction therapy for insomnia.

This study profiles changes in self-reported daytime functioning during sleep restriction therapy (SRT) for insomnia. Ecological momentary assessment (EMA) captured point-in-time symptomatology to map the time-course of symptoms. We hypothesized a deterioration (week 1) followed by improvements at week 3 of therapy relative to baseline. Nine patients with psychophysiological insomnia completed the Daytime Insomnia Symptom Scale (DISS) at rise-time, 12:00hours, 18:00hours and bedtime for 1week before and 3weeks during SRT. Four validated factors from the DISS were analyzed (alert cognition, positive mood, negative mood and sleepiness/fatigue) across 28days yielding 17170 data points. Factors evaluated week (baseline versus weeks 1 and 3) and time of day symptomatology. Insomnia Severity Index scores decreased significantly pre-to-post treatment (mean 18 versus 7). Reflecting acute effects of SRT, significant differences were found for all factors, except negative mood, between baseline and week 1 of SRT, suggesting adverse effects. By week 3, sleepiness/fatigue and negative mood decreased significantly compared to baseline, and positive mood showed a trend towards improvement (P=0.06). Sleepiness/fatigue displayed a significant week×time of day interaction, explained by a reduction in sleepiness/fatigue at every daytime assessment point (except bedtime, which remained high). A significant interaction for alert cognition was associated with reduction in alertness at bedtime by week 3 and an increase in alertness at rise-time, suggesting that SRT not only improves sleep, but moderates alertness and sleepiness in therapeutic ways. Initial SRT is associated with an increase in sleepiness/fatigue and a decrease in alert cognition.

No pain, no gain: An exploratory within-subjects mixed-methods evaluation of the patient experience of sleep restriction therapy (SRT) for insomnia

To explore the patient experience of Sleep Restriction Therapy (SRT) for insomnia, with particular focus on elucidating possible side-effects, challenges to adherence and implementation and perceptions of benefit/impact. To fully investigate the patient experience of sleep restriction therapy for insomnia we designed a within-subjects mixed-method study, employing sleep and daytime functioning questionnaires, assessments of sleep-restriction-related side-effects, prospective qualitative audio-diaries and post-treatment semi-structured interviews. University of Glasgow Sleep Centre. Eighteen patients with Primary Insomnia (mean age=42; range 18-64). Patients took part in a 4-week brief sleep restriction intervention, involving two group sessions and two subsequent follow-up phone calls in the home environment. Sleep diaries and global measures of insomnia severity and sleep quality, as expected, demonstrated robust improvements at both post-treatment and 3-month follow-up (all large effect sizes). Daytime functioning/health-related quality of life variables similarly evidenced strong treatment effects (moderate to large effect sizes). Reported side-effects were common, with ≥50% of patients reporting impairment in 8 out of 12 listed symptoms as a consequence of initiating treatment. The four most common side-effects were 'fatigue/exhaustion' (100%), 'extreme sleepiness' (94%), 'reduced motivation/energy' (89%) and 'headache/migraine' (72%) [Mean number of symptoms per patient=7.2 (2.4); range 3-11]. Intriguingly, both side-effect frequency and ratings of side-effect interference were associated with baseline to post-treatment improvements in sleep quality. Qualitative real-time audio-diaries during week 1 of treatment and post-treatment interviews provided rich accounts of side-effects associated with acute SRT implementation; general challenges surrounding treatment implementation and adherence/non-adherence; and modifications to sleep parameters, daytime functioning and perceptions of sleep/sleep period. This work has important implications for the delivery of SRT, particularly concerning awareness of possible 'adverse events' and likely implementation/adherence challenges. Findings also pave the way for testable hypotheses concerning possible mechanisms of action involved in sleep restriction treatment.