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. 2024 Aug;28(36):1–107. doi: 10.3310/RJYT4275

Nurse-delivered sleep restriction therapy to improve insomnia disorder in primary care: the HABIT RCT.

Simon D Kyle, Peter Bower, Ly-Mee Yu, Aloysius Niroshan Siriwardena, Yaling Yang, Stavros Petrou, Emma Ogburn, Nargis Begum, Leonie Maurer, Barbara Robinson, Caroline Gardner, Stephanie Armstrong, Julie Pattinson, Colin A Espie, Paul Aveyard
PMCID: PMC11367301  PMID: 39185919

Abstract

BACKGROUND

Insomnia is a prevalent and distressing sleep disorder. Multicomponent cognitive-behavioural therapy is the recommended first-line treatment, but access remains extremely limited, particularly in primary care where insomnia is managed. One principal component of cognitive-behavioural therapy is a behavioural treatment called sleep restriction therapy, which could potentially be delivered as a brief single-component intervention by generalists in primary care.

OBJECTIVES

The primary objective of the Health-professional Administered Brief Insomnia Therapy trial was to establish whether nurse-delivered sleep restriction therapy in primary care improves insomnia relative to sleep hygiene. Secondary objectives were to establish whether nurse-delivered sleep restriction therapy was cost-effective, and to undertake a process evaluation to understand intervention delivery, fidelity and acceptability.

DESIGN

Pragmatic, multicentre, individually randomised, parallel-group, superiority trial with embedded process evaluation.

SETTING

National Health Service general practice in three regions of England.

PARTICIPANTS

Adults aged ≥ 18 years with insomnia disorder were randomised using a validated web-based randomisation programme.

INTERVENTIONS

Participants in the intervention group were offered a brief four-session nurse-delivered behavioural treatment involving two in-person sessions and two by phone. Participants were supported to follow a prescribed sleep schedule with the aim of restricting and standardising time in bed. Participants were also provided with a sleep hygiene leaflet. The control group received the same sleep hygiene leaflet by e-mail or post. There was no restriction on usual care.

MAIN OUTCOME MEASURES

Outcomes were assessed at 3, 6 and 12 months. Participants were included in the primary analysis if they contributed at least one post-randomisation outcome. The primary end point was self-reported insomnia severity with the Insomnia Severity Index at 6 months. Secondary outcomes were health-related and sleep-related quality of life, depressive symptoms, work productivity and activity impairment, self-reported and actigraphy-defined sleep, and hypnotic medication use. Cost-effectiveness was evaluated using the incremental cost per quality-adjusted life-year. For the process evaluation, semistructured interviews were carried out with participants, nurses and practice managers or general practitioners. Due to the nature of the intervention, both participants and nurses were aware of group allocation.

RESULTS

We recruited 642 participants (n = 321 for sleep restriction therapy; n = 321 for sleep hygiene) between 29 August 2018 and 23 March 2020. Five hundred and eighty participants (90.3%) provided data at a minimum of one follow-up time point; 257 (80.1%) participants in the sleep restriction therapy arm and 291 (90.7%) participants in the sleep hygiene arm provided primary outcome data at 6 months. The estimated adjusted mean difference on the Insomnia Severity Index was -3.05 (95% confidence interval -3.83 to -2.28; p < 0.001, Cohen's d = -0.74), indicating that participants in the sleep restriction therapy arm [mean (standard deviation) Insomnia Severity Index = 10.9 (5.5)] reported lower insomnia severity compared to sleep hygiene [mean (standard deviation) Insomnia Severity Index = 13.9 (5.2)]. Large treatment effects were also found at 3 (d = -0.95) and 12 months (d = -0.72). Superiority of sleep restriction therapy over sleep hygiene was evident at 3, 6 and 12 months for self-reported sleep, mental health-related quality of life, depressive symptoms, work productivity impairment and sleep-related quality of life. Eight participants in each group experienced serious adverse events but none were judged to be related to the intervention. The incremental cost per quality-adjusted life-year gained was £2075.71, giving a 95.3% probability that the intervention is cost-effective at a cost-effectiveness threshold of £20,000. The process evaluation found that sleep restriction therapy was acceptable to both nurses and patients, and delivered with high fidelity.

LIMITATIONS

While we recruited a clinical sample, 97% were of white ethnic background and 50% had a university degree, which may limit generalisability to the insomnia population in England.

CONCLUSIONS

Brief nurse-delivered sleep restriction therapy in primary care is clinically effective for insomnia disorder, safe, and likely to be cost-effective.

FUTURE WORK

Future work should examine the place of sleep restriction therapy in the insomnia treatment pathway, assess generalisability across diverse primary care patients with insomnia, and consider additional methods to enhance patient engagement with treatment.

TRIAL REGISTRATION

This trial is registered as ISRCTN42499563.

FUNDING

The award was funded by the National Institute of Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 16/84/01) and is published in full in Health Technology Assessment; Vol. 28, No. 36. See the NIHR Funding and Awards website for further award information.

Plain language summary

Insomnia refers to problems with falling asleep or staying asleep, which affects 10% of the adult population. The recommended treatment for insomnia is a psychological treatment called cognitive–behavioural therapy. Research shows this to be a very effective and long-lasting treatment, but there are not enough trained therapists to support the large number of poor sleepers in the United Kingdom. We have developed a brief version of cognitive–behavioural therapy, called sleep restriction therapy, which involves supporting the patient to follow a new sleep–wake pattern. We carried out this study to see if sleep restriction therapy, given by nurses working in general practice, can improve insomnia and quality of life. We searched general practice records and invited people with insomnia to take part. Six hundred and forty-two participants were assigned, by chance, to either sleep restriction therapy or a comparison treatment, called sleep hygiene. Sleep restriction therapy involved meeting with a nurse on four occasions and following a prescribed sleep schedule. Sleep hygiene involved receiving a leaflet of sleep ‘do’s and dont’s’. Those receiving sleep restriction therapy were also provided with the same sleep hygiene leaflet so that the difference between the two groups was whether or not they received nurse treatment. We measured sleep, quality of life, daytime functioning and use of sleep medication through questionnaires, before and after treatment. We calculated the cost to deliver the treatment, as well as the cost of other National Health Service treatments that participants accessed during the study. We also interviewed participants and nurses to understand their views of the treatment. We found that participants in the sleep restriction therapy group experienced greater reduction in their insomnia symptoms compared to sleep hygiene. They also experienced improved sleep, mental health, quality of life and work productivity. The two groups did not differ in their use of prescribed sleep medication. Our results suggest that the treatment is likely to represent good value for money for the National Health Service. Both nurses and participants considered the treatment to be acceptable and beneficial, and they suggested some potential refinements. The study shows that nurse-delivered sleep restriction therapy is likely to be a clinically effective approach to the treatment of insomnia, and good value for money for the National Health Service.

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