The impact of symptom clusters on endocrine therapy adherence in patients with breast cancer.

BACKGROUND: When taken as prescribed, endocrine therapy is effective in reducing risk of recurrence and mortality in the treatment of patients with breast cancer. However, treatment side effects can act as a barrier to medication adherence. Existing research has not identified any specific side effects as consistent predictors of nonadherence. Our aim was to explore the influence of symptom clusters on self-reported adherence in patients with breast cancer. METHODS: A cross-sectional online survey was conducted, including patients with breast cancer currently or previously prescribed endocrine therapy (N = 1051). This included measures of self-reported endocrine therapy adherence and common symptoms among this population (insomnia, depression, anxiety, fatigue, musculoskeletal, and vasomotor symptoms). RESULTS: Unintentional nonadherence was higher than intentional nonadherence (50.8 % vs 31.01 %). The most troublesome symptom was insomnia (73.83 % displayed probable insomnia disorder). K-means cluster analysis identified 2 symptom clusters: overall High symptoms, and overall Low symptoms. Participants in the Low symptoms cluster were significantly more likely to be classed as adherent based on unintentional and intentional items. CONCLUSIONS: Nonadherence was high in the current sample, and significantly more likely in participants reporting overall severe symptoms. Clinicians should be aware of the scale of common side effects and facilitate open conversation about potential barriers to adherence. Follow-up care should include assessment of common symptoms and signpost patients to appropriate support or treatment when required. Future research should explore potential for a central symptom to act as a target for intervention, to relieve overall side effect burden and facilitate better medication adherence.

Insomnia prehabilitation in newly diagnosed breast cancer patients: Protocol for a pilot, multicentre, randomised controlled trial comparing nurse delivered sleep restriction therapy to sleep hygiene education (INVEST trial).

INTRODUCTION: Insomnia is a prevalent sleep disorder that negatively impacts daytime functioning and quality of life. Breast cancer patients report higher rates of insomnia and more circadian disruption than other cancer groups. Approximately 50% of patients experience acute insomnia following breast cancer diagnosis, which often persists during cancer treatment and rehabilitation. Sleep Restriction Therapy (SRT) is a clinically effective and tolerable treatment for persistent insomnia in breast cancer survivors. However, SRT has never been tested on patients with early signs of sleep disturbance who are undergoing cancer treatment. The aim of this pilot randomised controlled trial is to explore the feasibility and preliminary effectiveness of nurse delivered SRT for newly diagnosed breast cancer patients with acute insomnia. The trial has been registered on ClinicalTrials.gov (identifier: NCT06294041). METHODS: The INVEST (INvestigating the Value of Early Sleep Therapy) trial will recruit 50 newly diagnosed breast cancer patients who meet criteria for acute insomnia. Patients will be recruited from breast cancer results clinics within two Scottish health boards (NHS Grampian and NHS Greater Glasgow and Clyde) and will be block randomised (1:1) to receive nurse delivered SRT or Sleep Hygiene Education (SHE). SRT will be delivered over 4 weekly sessions comprising two face-to-face meetings (either in person or online) and two telephone calls, whereas SHE will be administered in booklet form. Outcomes will be collected at baseline, 6 weeks, and 12 weeks post-randomisation. Primary outcomes in this trial relate to the feasibility of SRT for newly diagnosed breast cancer patients with acute insomnia. Specifically, we will explore (i) rates of patient recruitment and retention, (ii) intervention fidelity, (iii) data collection procedures and outcome measure completion, (iv) intervention acceptability. Secondary outcomes will focus on preliminary evaluation of patient responses to SRT, including insomnia severity, rest-activity rhythms, and mental health. DISSEMINATION: Our dissemination plan comprises publishing trial outcomes in high-impact, peer-reviewed journals and on breast cancer charity websites and other patient resources. The outcomes from this pilot trial will also inform the development of a full-scale, multicentre RCT of SRT for acute insomnia in newly diagnosed breast cancer patients. University of Strathclyde is the sponsor (reference: UEC23/52). Protocol version v1.2 4 October 2023. STRENGTHS AND LIMITATIONS OF THIS STUDY: This trial is the first to explore the value of sleep prehabilitation for newly diagnosed breast cancer patients.This will be the first trial to assess the feasibility of delivering SRT during breast cancer treatment, providing valuable insight into its tolerability and preliminary effectiveness.An embedded process evaluation will assess the acceptability of SRT, providing insight into potential optimisation of the intervention and recommendations for enhancing its future scalability and translation within cancer care.Due to the nature of the SRT intervention, nurse therapists and patients cannot be blinded to treatment allocation, increasing the risk of bias.