Twenty percent of breast cancer survivors have insomnia, which is defined as persistent trouble falling and/or staying asleep that results in difficulty functioning during the day. Sleep difficulties often begin at cancer diagnosis, become worse during cancer treatment, and continue into cancer survivorship. Insomnia interferes with daily activities and may cause other mental and physical health problems. It also makes it more difficult to cope with cancer treatment and makes recovery more challenging. For these reasons, it is important to address early signs of sleep problems in cancer patients by offering interventions that may prevent the development of insomnia.

Sleep Restriction Therapy is one such intervention, which helps improve night-time sleep by stabilising sleep patterns and reducing time spent in bed awake. Sleep Restriction Therapy has been used successfully to treat chronic insomnia in breast cancer survivors who have completed cancer treatment. However, it has never been tested on newly diagnosed breast cancer patients with early signs of sleep disturbance, who are undergoing cancer treatment.

This study will address this knowledge gap by randomly assigning newly diagnosed patients with poor sleep to receive either Sleep Restriction Therapy or a sleep hygiene education (SHE) control intervention. The study will assess sleep and mental health before and after both interventions to determine how feasible and acceptable Sleep Restriction Therapy is to patients and to plan for a future, larger study. Throughout, the investigators will work with patients with lived experience of breast cancer and poor sleep to ensure our study is informed by their expertise.

The primary aim of this project is to assess the feasibility and inform the design of a full-scale RCT of SRT for newly diagnosed breast cancer patients with acute insomnia. Secondary aims of this project are to assess the effects of SRT alongside a sleep hygiene education (SHE) control on sleep, rest-activity rhythms, and mental health.

Participants will be recruited from breast cancer results clinics in two study sites. Our target population is newly diagnosed, non-metastatic patients whose primary cancer treatment is surgery. Participants will go through initial screening and will be sent an online participant information sheet and consent form. Once consent form is signed, marking enrolment in the study, the second stage of screening will commence. It involves assessing current sleep status (based on diagnostic criteria for acute insomnia) current psychiatric symptoms and review of other relevant medical information (diagnosis of other sleep disorders, other medical and psychiatric disorders). This is to confirm the diagnosis of acute insomnia and establish that there are no medical or psychiatric conditions that might preclude someone from taking part in the study. Once eligibility is ascertained, patients will be randomly assigned to SRT or the SHE control group. The investigators aim to randomise 50 patients (n=25 in each trial arm).

After randomisation to SRT or SHE, patients will be sent an email with a link to complete a baseline (pre-intervention) assessment of sleep, fatigue, and mental health. Patients will also be required to complete the consensus sleep diary and wear an actigraphy device for 7 days prior to commencement of SRT/SHE to record sleep and rest/activity rhythms. After completion of the baseline assessment, patients will either be referred to the research nurse for commencement of the SRT protocol or provided with the SHE resource. At 6 weeks, and 3 months post-randomisation, patients will be requested to complete the same battery of questionnaires as during the baseline assessment. Following completion of the final study assessment (3 months post-randomisation), those randomised to the SHE condition will be offered the opportunity to complete the SRT protocol without the requirement to complete any further assessments.

Interventions: Sleep Restriction Therapy (SRT)

SRT is a manualised, adaptive, behavioural insomnia intervention that is a key active ingredient within multi-component CBT-I. Those randomised to the SRT arm will receive two online sessions supported by two telephone calls over a 4-week intervention phase. SRT will be delivered by trained research nurses.

Sleep Hygiene Education (SHE)

SHE will be delivered via a booklet that provides information about lifestyle changes (e.g., reducing exercise in the evening, light snack before bedtime, reducing caffeine) and changes to the bedroom environment (e.g., dark room, comfortable mattress, optimal room temperature). Patients in the SHE condition will be instructed to implement the SHE advice over a 4-week period.

Inclusion Criteria:

Participant is willing and able to give informed consent

Aged 18 years and above

Screen positive for acute insomnia, defined as dissatisfaction with sleep quality or duration, accompanied by other night / daytime symptoms, present for between 2 weeks and 3 months

Newly diagnosed with non-metastatic breast cancer

Primary cancer treatment is surgery

Exclusion Criteria:

• Main study exclusion criteria are limited to conditions contraindicated for SRT or factors that would preclude implementation of SRT.

  1. Pregnancy
  2. Additional sleep disorder diagnosis (e.g., restless legs syndrome, obstructive sleep apnoea, narcolepsy) or screen "positive" for additional sleep disorder at study screening interview
  3. Dementia / Mild Cognitive Impairment
  4. Epilepsy
  5. Psychosis (schizophrenia, bipolar disorder)
  6. Current suicidal ideation with intent or attempted suicide within past 2 months
  7. Night, evening, early morning, or rotating shiftwork
  8. Current / previous psychological treatment for insomnia during the last 12 months
  9. Chemotherapy and / or radiotherapy commenced

Due to the nature of the SRT intervention, the research nurse, patients and most of the study team cannot be blinded to treatment allocation. However, the statistician will be blinded to treatment allocation (i.e., SRT or SHE) until after analysis is complete