Sleep as an additional painkiller

Background
Chronic pain is a pervasive experience that significantly impacts daytime functioning and disrupts sleep. Sleeplessness (insomnia) exacerbates patients’ chronic pain and diminishes overall well-being and functioning. Moreover, the interplay between chronic pain and insomnia can escalate into a vicious cycle, hindering pain treatments' effectiveness, increasing the risk of a new pain problem after successful treatment, and therefore unnecessarily prolonging patient suffering as well as increases costs of pain healthcare.

The hypothesis of this study is that enhancing standard pain treatment by adding an internet-based, guided Cognitive Behavioural Therapy for Insomnia (i-CBT-I) at the start of pain treatment may alleviate patient suffering and reduce
healthcare costs associated with pain healthcare.

Objectives
The objective of the study is to investigate whether adding i-CBT-I at the start of standard pain treatment can enhance pain healthcare by reducing patient suffering and costs compared to Treatment As Usual (TAU). Our analyses will examine whether patient characteristics (such as having comorbid mental health problems) influence this effect. Additionally, we seek to evaluate whether providing a brief neuroscience educational film prior to i-CBT-I explaining the vicious cycle between sleep and pain improves the effectiveness and implementation of i-CBT-I. Lastly, we aim to identify factors that facilitate or hinder i-CBT-I implementation in the daily practice of a Pain Medicine outpatient clinic.

Design
The study is a monocentric, pragmatic, randomised single-blind controlled trial, enrolling 182 patients. Patients will be randomised on a 1:1:1 basis to receive either i-CBT-I, i-CBT-I preceded by a brief neuroscientific educational film (i-CBT-I+) or TAU. Assessments will be conducted at baseline, upon completion the i-CBT-I or control condition and six months after completion of the i-CBT-I or control condition.

Study population
The study population are Dutch-speaking, chronic pain patients with insomnia aged 18 years and older, who have been newly referred to a Pain Medicine outpatient clinic.

Intervention
The i-CBT-I utilised in our study, referred to as i-Sleep, consists of five online sessions covering the following topics: sleep psychoeducation, sleep hygiene, sleep habits/lifestyle, sleep rhythm, cognitive strategies and relaxation. To customize i- Sleep while minimizing costs, therapists and patients communicate via text messages within the i-Sleep application.

Primary outcome
The primary outcome measure is the difference in insomnia severity between the intervention group (with and without the educational film) and the control group, as measured by the 7-item Insomnia Severity Index.

Secondary outcome
Secondary outcome measures include the differences in level of physical, emotional and social well-being and functioning, standard pain treatment duration, complexity, and costs.
To identify the facilitating and hindering factors for implementing i-CBT-I in the daily practice, we will evaluate the effect of the educational film on adherence to the i-CBT-I and we will conduct semi-structured interviews with key stakeholders.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness
Participating in the study entails completing assessments and, if randomised to i-CBT-I, adhering to the treatment, bothvof which require time and energy from patients. To minimize nocturnal discomfort, we utilise a sleep monitoring system
positioned under the mattress rather than physically attached to the patient, ensuring minimal disruption to sleep and adherence to the research protocol.

Patients undergoing i-CBT-I may experience a reduction in insomnia, potentially improving physiological, psychological, and social well-being and functioning. However, i-CBT-I may also lead to temporary side effects, including sleep
disturbances, fatigue, daytime sleepiness, loss of motivation/energy, and headaches. Patients will be informed in advance about these potential side effects.