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Mental health
Protocol
Effectiveness of digital Cognitive-Behavioural Therapy for Insomnia in patients with musculoskeletal complaints and insomnia in primary care physiotherapy: study protocol for a randomised controlled trial
  1. Eivind Schjelderup Skarpsno1,2,
  2. Jonas Grevle Hofmo1,
  3. Maria Hrozanova1,
  4. Øystein Vedaa3,4,
  5. Astrid Woodhouse5,6,
  6. Tormod Landmark5,6,
  7. Lennart Bentsen7,
  8. Jonas Bloch Thorlund8,9,
  9. Anne Lovise Nordstoga7,
  10. Ingebrigt Meisingset1,10
  1. 1Department of Public Health and Nursing, Norwegian University of Science and Technology, Trondheim, Norway
  2. 2Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim, Norway
  3. 3Department of Health Promotion, Norwegian Institute of Public Health, Bergen, Norway
  4. 4Department of Psychosocial Science, University of Bergen, Bergen, Norway
  5. 5Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
  6. 6Department of Pain and Complex Disorders, St. Olavs Hospital, Trondheim, Norway
  7. 7Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
  8. 8Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
  9. 9Research Unit for General Practice, Department of Public Health, University of Southern Denmark, Odense, Denmark
  10. 10Unit for Physiotherapy Services, Trondheim Municipality, Trondheim, Norway
  1. Correspondence to Dr Eivind Schjelderup Skarpsno; eivind.s.skarpsno{at}ntnu.no

Abstract

Introduction Insomnia is prevalent among patients visiting physiotherapists due to musculoskeletal complaints and associated with poorer pain prognosis. Cognitive-Behavioural Therapy for Insomnia (CBT-I) may be effective for improving sleep quality and pain-related outcomes in these patients, but its availability and utility are limited in daily physiotherapy practice. The aim of this randomised controlled trial (RCT) is to evaluate the effectiveness of digital CBT-I in addition to usual treatment in patients with chronic musculoskeletal complaints and insomnia, compared with usual treatment only.

Methods and analysis In this RCT, eligible and consenting participants will be randomised (1:1 ratio) to one of two interventions: (1) digital CBT-I adjunct to physiotherapy treatment or (2) usual physiotherapy treatment. Patients with musculoskeletal complaints and insomnia visiting a physiotherapist in Norway will be invited to participate in the study. We aim to include 188 participants to detect a difference in the primary outcome. Outcome variables will be assessed at baseline (prior to randomisation) and at 6-week, 3-month, 6-month and 12-month follow-up. The primary outcome is between-group difference in insomnia severity, assessed with the Insomnia Severity Index (0–28 points) at 3 months. Secondary outcomes include between-group differences in pain intensity, physical function, work ability, health-related quality of life, mental distress, and self-reported use of sleep and pain medication. Exploratory analyses will identify patient characteristics influencing the effect of the digital intervention.

Ethics and dissemination This trial is approved by the Regional Committee for Medical and Health Research Ethics in Central Norway (Ref. 2023/533381). The results of the trial will be published in peer-review journals and disseminated at national and international conferences.

Trial registration number ISRCTN91221906.

  • chronic pain
  • sleep medicine
  • musculoskeletal disorders
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https://doi.org/10.1136/bmjopen-2023-083592

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    STRENGTHS AND LIMITATIONS OF THIS STUDY

    • This study includes a wide range of subjective measures, an extended follow-up period and linkage to national registers (sick leave, healthcare utilisation, medication).

    • The effectiveness of digital sleep therapy is limited to patients who have a smartphone and adequate digital literacy skills to engage with the intervention.

    • The effect might also be limited by low adherence to the main components of the therapy (ie, sleep restriction and stimulus control) or by lack of tailored digital support.

    • Due to the nature of the intervention patients will not be blinded to treatment allocation.

    Introduction

    More than half of the patients with musculoskeletal complaints seeking physical therapy services report insomnia symptoms.1 Insomnia in patients with chronic pain is associated with greater pain intensity,2 lower pain tolerance3 and lower probability of pain relief,4 5 indicating that improving sleep quality should be a therapeutic target in patients with comorbid musculoskeletal complaints and insomnia. Cognitive Behavioural Therapy for Insomnia (CBT-I) is the recommended treatment for insomnia due to its long-term effectiveness.6 An increasing number of randomised controlled trials (RCTs) have shown that CBT-I in patients with comorbid chronic pain and insomnia is effective in reducing insomnia symptoms, but with inconsistent findings for other health outcomes such as pain, depression and fatigue.7

    Although CBT-I is a promising treatment option for patients with musculoskeletal complaints and insomnia, constraints in resources and lack of training in cognitive therapy prevent CBT-I from being regularly offered by physiotherapists. A viable alternative is to use a self-guided and fully automated digital version of the CBT-I intervention delivered via mobile app as an adjunct to usual care.8 9 Digital CBT-I (dCBT-I) is effective for people with insomnia8 9 but only a few studies have assessed the effectiveness of web-based CBT-I among patients with comorbid insomnia and chronic pain with promising results.10 11 Although promising results, we need sufficiently powered trials to give any recommendations of using dCBT-I as an add-on for patients with pain and insomnia in primary care. Moreover, it is still unclear where in the healthcare system digital interventions ought to be implemented. Understanding the effectiveness and utility of dCBT-I in this patient group could therefore have the potential to aid the clinician in improving the treatment outcomes of their patients.

    In addition to studying the effectiveness of dCBT-I, there is lack of empirical evidence that inform clinicians in primary care about who would benefit from dCBT-I. The multidimensional array of individual characteristics and prognostic factors among patients in primary care makes it challenging to optimise management.12 Insomnia and pain often co-occur with symptoms of depression and anxiety,13 14 and the presence and number of comorbid conditions appear to distinguish between people with different insomnia severity.15 Moreover, patients with insomnia with unhelpful beliefs about sleep may have a lower response to CBT-I.16 17 Knowledge about whether such patient characteristics influence the therapeutic response of dCBT-I can help to better identify patients who are likely to benefit from the treatment, and potentially better tailor the therapy to people with common characteristics that are associated with poor prognosis.

    Aim and objectives

    The primary aim of the RCT is to evaluate the effectiveness of dCBT-I on insomnia severity in patients with musculoskeletal complaints and insomnia in primary care physiotherapy in Norway. The primary outcome measure is insomnia severity at 3-month follow-up. The secondary outcome measures are physical function, pain intensity, health-related quality of life, mental distress, work ability, and self-reported use of sleep and pain medication.

    In an additional publication, we will also assess primary and secondary outcomes up to 12 months after baseline assessment to test if there are any long-term effects of using dCBT-I. This study will also compare sick leave days, use of prescribed medication (eg, psychotropics, sedatives) and healthcare resource utilisation, using national registry data at 12-month post-treatment between the intervention and control group.

    If the sample size allows it, we will also conduct exploratory analyses to identify individual traits that influence the effectiveness of dCBT-I (eg, psychological distress, pain phenotypes, number of pain sites, patient’s beliefs about the treatment, insomnia severity, duration of pain and insomnia, reactivity to stress, chronotype, digital literacy skills). Additionally, it might be relevant to conduct exploratory mediation analyses to identify possible mechanisms behind change in the primary and secondary outcomes, focusing on pain-related beliefs and attitudes about sleep as potential mediators.

    Methods and analyses

    This RCT protocol follows the SPIRIT guidelines (Standard Protocol Item for Randomised Trials)18 (see online supplemental appendix 1) and the study will be carried out according to relevant guidelines and regulations. Figure 1 shows the flow chart for the recruitment and assessments during the trial. The RCT started the recruitment on 1 May 2023. The recruitment phase is planned to last until 31 March 2025. Data analyses will take place once the RCT is finalised, and the primary paper is expected to be completed within 31 December 2026. According to ethical guidelines, the data will be stored for documentation and control purposes for 5 years thereafter, until 31 December 2031.

    Figure 1
    Figure 1

    Participants’ flow chart. dCBT-I, digital Cognitive Behavioural Therapy for Insomnia; ISI, Insomnia Severity Index.

    Study population and trial design

    The trial is designed as a block-RCT with two arms. The setting is private practice physiotherapy in primary care in Norway. The trial is prospectively registered in Open Science Frameworks and a database for clinical studies (ISRCTN Registry (REF. ISRCTN91221906)). Assessments will be carried out at five different time points during the RCT: at baseline before randomisation with follow-up at 6 weeks, 3 months (primary outcome), and long-term follow-up at 6 and 12 months.

    Inclusion and exclusion criteria

    Inclusion criteria for the RCT are patients in working age (18–67 years) with persistent musculoskeletal complaints (≥3 months) as the primary reason for seeking physiotherapy. Patients with different musculoskeletal disorders (eg, low back pain, neck pain, shoulder pain, osteoarthritis, widespread pain, sciatica, tendonitis) can be study participants. In addition, the patients must report having insomnia, defined as an Insomnia Severity Index (ISI) score of 12 points or higher, indicating insomnia symptoms with a significant impact on the individual.19 Moreover, the insomnia symptoms must have been present for ≥3 months. Exclusion criteria were reduced cognitive function (dementia, etc), specific diagnosis such as fractures, neurological conditions (ie, stroke, multiple sclerosis, etc), untreated sleep apnoea, terminal or progressive illness (eg, receiving treatment for cancer), planned surgery, postoperative patients who underwent surgery in the last 6 months, pregnant or pregnancy-related disorders, not having access to a smartphone or tablet, inadequate opportunity to have regular sleep or living circumstances that prevent modification of sleep patterns such as night shifts, currently receiving psychological treatment for insomnia, a medical history of contraindicated use of CBT-I such as epilepsy and recent cardiac surgery.

    Recruitment and randomization

    Physiotherapists working in private practice physiotherapy clinics in Norway will recruit patients to the study by asking patients the following question: ‘Do you have sleep problems (eg, difficulty initiating sleep, trouble maintaining sleep or early morning awakenings) that influence important aspects of your life?’. If they respond ‘yes’, they will receive a leaflet with information about the study. Interested participants will enter a secure online screening portal by scanning a QR code uniquely created for this project. In the screening portal, participants will be asked to complete a series of self-rating questions to ensure that they meet eligibility criteria. Eligible participants will be sent a digital consent form. After consenting to participate in the study, participants will complete a web-based questionnaire for the baseline assessment, and thereafter be randomised to the intervention or control group (1:1 allocation ratio). We will use block randomization to ensure a balance in sample size across groups over time.

    Blinding is impossible since the participants will know whether they receive dCBT-I. The randomisation procedure will be performed in the secure digital platform for multicentre clinical studies, eForsk. In eForsk, a third-party user from the Clinical Research Unit (Klinforsk) at The Faculty of Medicine and Health Sciences at the Norwegian University of Science and Technology (NTNU) will set up the randomisation procedure blinded to the researchers. After randomisation, the patient will receive information about how to download the app. The patients will also be contacted by our research team to secure that they download the app and to clarify questions the patients might have before starting the intervention.

    Interventions

    Usual physiotherapy care

    Participants in the control group will receive usual treatment as deemed appropriate by their physiotherapist. This includes any diagnostic procedure, treatment or referral the physiotherapist finds relevant based on the medical history, clinical findings and pragmatic, daily clinical practices to address musculoskeletal complaints. Participants are allowed to seek care and treatment elsewhere as they find relevant. After the completion of the long-term follow-up at 12 months, participants in the control group will be offered to use the app given to the intervention group.

    dCBT-I in addition to usual physiotherapy care

    Participants randomised to dCBT-I will receive the sleep intervention delivered via a smartphone app. The trial will use a Norwegian dCBT-I programme named Assistert Selvhjelp (In English: ‘Assisted Self-Help’, website: https://assistertselvhjelp.no/). The app consists of six interactive sessions and requires no contact with the physiotherapist (table 1). The sleep intervention consists of a self-managing dCBT-I programme based on the principles from face-to-face CBT-I including sleep hygiene, stimulus control (pairing the bed with sleep), sleep restriction (reducing time in bed to increase sleep pressure), cognitive therapy (challenging dysfunctional thoughts about sleep loss) and relaxation training. The modules also consist of learning material (eg, quizzes and materials explaining and educating the patients about important aspects about sleep). Patients will be recommended to use the app during the first 6 weeks (one module per week) after starting the physiotherapy treatment but are allowed to use the app in their own pace and during the whole project period. Patients will receive tasks in the modules (eg, write sleep diary, practice sleep restriction and change lifestyle behaviour) that facilitates self-management and focuses on an active role to reduce insomnia symptoms. They will receive weekly notifications in the app during follow-up to encourage adherence to the modules. The physiotherapist will not have specific knowledge of the patients' progress in the dCBT-I intervention and will also not address this in the physiotherapy treatment, unless this is a topic raised by the patient.

    View this table:
    Table 1

    Description of digital CBT-I sessions during the intervention period

    Assessments

    The primary outcome will be insomnia severity assessed by the ISI20 at 3 months after the baseline assessment. Three months was chosen as the timepoint for the primary analysis to allow sufficient time to complete the digital intervention. Secondary outcomes include physical function, pain intensity, health-related quality of life and work ability. Health information that will be obtained in this study includes the screening questionnaire and the questionnaire battery. Additionally, we will use the participants’ social security numbers to link the collected data to national health registries on rates of sick leave, as well as medication and health resource utilisation. Self-reported health information will be collected using the eForsk platform, which offers secure solutions for participant-filled forms distributed through Helsenorge.no or a secure digital mailbox (Digipost or e-Boks). Once the self-reported data collection is complete, an anonymised database will be exported from eForsk, sufficiently encrypted and stored within the NTNU file system. The participant identification key will be confidential and stored separately from the database, only accessible to the project leaders.

    Questionnaires and variables

    Tables 2 and 3 show all patient-reported information and outcomes collected by questionnaires at the different measurement timepoints of data collection. The questionnaires are a combination of validated questionnaires and single items, and single items developed by the research group in the absence of established questionnaires. In addition to demographic characteristics, the baseline questionnaire assesses domains related to lifestyle and health-related parameters, sleep and circadian rhythms, pain, psychological factors related to sleep and pain, other physical and mental health problems, and patient’s beliefs/expectations to physiotherapy treatment and sleep treatment via app. The follow-up questionnaires contain repeated measures of some of the baseline questionnaires used to evaluate outcome measures, specific questions regarding the physiotherapy treatment and use of the app (tables 2 and 3).

    View this table:
    Table 2

    The questionnaires or wording of sociodemographic, lifestyle-related and health-related variables, and schedule of assessment

    View this table:
    Table 3

    The questionnaires or wording of sleep-related, pain-related and app-related variables, and schedule of assessment

    Primary outcome measure

    The primary outcome is self-reported insomnia severity assessed by ISI,20 consisting of seven items assessing symptoms of insomnia such as difficulty falling or staying asleep, satisfaction with sleep and degree of impairment with daytime functioning. The total score of ISI ranges from 0 to 28 points, where a higher score indicates more insomnia severity. The ISI has been validated extensively and has proven sensitive to therapeutic changes.20

    Secondary outcomes

    The secondary outcomes in the study include pain intensity, function, health-related quality of life, work ability and self-reported use of sleep and pain medication (see tables 2 and 3). In an additional paper, we will assess the long-term effects of dCBT-I on secondary outcomes as well as sick leave, healthcare resource utilisation and use of both self-reported and prescribed pain and sleep medication.

    Statistical analyses

    A detailed statistical analysis plan will be published before unblinding of study data. Analysis and interpretation of the study results will be performed by researchers blinded to group allocation.

    Descriptive statistics

    Descriptive statistics will be presented stratified by group allocation. Categorical and binary variables will be presented as counts and percentages, continuous variables will be presented as means and SD or medians and IQR, as appropriate.

    Analysis of primary and secondary outcomes

    Analyses of primary and secondary outcomes will be performed according to the intention-to-treat principle. The primary analysis will estimate mean differences with 95% CIs in ISI between the two groups at 3-month follow-up using a linear mixed model. We plan to use linear mixed-model analysis to examine the change between baseline and postintervention on the primary and secondary outcome with continuous variables (ie, insomnia severity, health-related quality of life, pain intensity, work ability). The model will include time, time–group interaction and potentially important predictors of the outcome including baseline score.21 For binary secondary outcomes (eg, clinically relevant change in ISI, use of sleep and pain medication), logistic mixed-model analysis will be used. Planned sensitivity analyses of the primary outcome include complete case analysis including participants with data at all time points and per-protocol analyses for individuals who complete the four first dCBT-I modules (including sleep restriction and stimulus control). We will also explore the effect of level of adherence to specific components of the CBT-I (sleep hygiene, sleep restriction, relaxation techniques on the primary outcome in those who received dCBT-I).

    Moderator and mediation analyses

    In additional publications, we plan to conduct exploratory analyses to identify moderators of the effectiveness of the dCBT-I (eg, psychological distress, pain phenotypes,22 number of pain sites, patient’s beliefs about the treatment, insomnia severity, duration of pain and insomnia, reactivity to stress, chronotype, digital literacy skills). Likewise, we will conduct exploratory mediation analyses to identify mechanisms behind change in the primary and secondary outcomes, focusing on pain-related beliefs and attitudes about sleep as potential mediators. We will follow the international, consensus-based guidance for the reporting of mediation analyses of randomised trials.23

    Sample size

    The study will be powered to detect a difference of 3 points between the dCBT-I group and the control group in the primary outcome (ISI) at 3 months follow-up. Some recent and comparable RCTs were used as a basis to define the effect size and expected SD for the current project.8 24 These studies show that the intervention effect in ISI from baseline to after intervention was 2.8–4.7 points in the intervention group compared with the control group.8 11 We therefore estimated that a sample size of 144 (72 in each group) was necessary to detect a 3-point difference with 90% power and a 2-sided alpha level of .05. Previous RCTs of dCBT-I report sample attrition rates between 12% and 50%.8 25 To allow for a 30% dropout rate at 3 months follow-up, we aim to include 188 participants (94 participants in each arm) to answer our primary aim.

    Stopping rule

    If the intended sample size is not reached during the intended recruitment period, the inclusion of participants will stop at 140 participants (70 participants in each arm), which will ensure adequate statistical power to detect a 3-point difference with 80% power, anticipating a 30% dropout rate during the follow-up.

    Ethics and dissemination

    The protocol has been approved by the Regional Committee for Medical and Health Research Ethics in Central Norway, REK (ref: 533381, see online supplemental appendix 2). All participants will be informed about the study and sign a consent before study entry (see Participant Consent Form in online supplemental appendix 3). They will be informed that they can withdraw from the study at any time without any consequences for their future rehabilitation. Some important ethical considerations involve the imposed participant burden of time and effort necessary to fill out the questionnaires. The burden is especially relevant for the control group, which do not get any additional sleep therapy. However, the control group will be offered to use the app after 12 months.

    We have conducted a feasibility study including five patients to determine the likelihood of it succeeding and to test the burden associated with use of the app and the baseline questionnaires. No considerable participant burden is expected. To increase the response rates from the participants, three randomly selected participants will get a tablet after they have completed all the measurement points. A success criterion and important risk mitigation for the project is that the physiotherapists have minimal additional work in the recruitment and follow-up of patients, since the dCBT-I intervention is an add-on to usual treatment given by the physiotherapist.

    It will not be possible to identify individual participants from the information provided in the disseminated results. The research topics will provide information on outcomes for potentially vulnerable patient groups with chronic pain and insomnia accompanied by poor mental health, and the dissemination of results will be discussed with user groups to reduce possible stigma related to results. Data storage and analysis will be conducted according to NTNU’s regulation and follow the General Data Protection Regulation. Results of the RCT will be disseminated to the scientific community in peer-reviewed publications and conference presentations and presented to relevant clinicians and user groups through workshops. We will also share a newsletter with relevant patient organisations, web-based new channels and blogs. The first publication will focus on the effectiveness of the dCBT-I intervention on primary and secondary outcomes. Further publications will explore the effectiveness of relevant patient-related and sleep-related characteristics on the primary and secondary outcomes. We do not expect to use any of the data or results for commercial purposes.

    Data monitoring

    On a weekly basis, the principal investigator and members of the research team will review the recruitment, enrolment, data collection and conduct of the intervention. If needed, the team will discuss appropriate actions to any inconsistencies or unexpected events. If needed, we will involve clinical representatives from participating clinics, statistical advisors and administrative leaders. The trial sponsor requires yearly updates of the project, ensuring that trial protocols and ethical standards are followed. If any important protocol amendments are necessary, these must be evaluated and approved by the ethics committee.

    Adverse events

    We acknowledge that dCBT-I is not without potential for adverse events. Sleep restriction may cause increased sleepiness, reduced daytime functioning and reductions in alert cognition.26 Therefore, to monitor and report adverse events, the trial includes questions about whether the participants experienced more sleep problems, pain, anxiety, unpleasant feelings due to the app, or if they visited their general practitioner or were admitted to hospital during the study period.

    Patient and public involvement

    A trained user representative has been involved in the planning of this study by giving feedback on the aims of the trial, the assessments included in the protocol, the questionnaires and the recruitment strategy. The user representative will also recruit other users who will participate in user panel meetings where the user representatives will provide important input to the scientific approaches, the results, and the dissemination process.

    Ethics statements

    Patient consent for publication

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    Supplementary materials

    Footnotes

    • X @E_Skarpsno, @Maria_Hrozanova, @jbthorlund, @meisingsinge

    • Contributors ESS and IM conceived the idea for the study. ESS and IM designed the trial with input from JGH, MH, OV, AW, TL, LB, JBT, ALN. ESS and IM designed the planned analyses. ESS, JGH and IM drafted the first version of the manuscript with input from all authors. All authors have approved the final version of the manuscript. ESS is the guarantor of this manuscript and accepts full responsibility for the conduct of the study.

    • Funding This trial received a PhD grant to Jonas Grevle Hofmo from the Norwegian Fund for Postgraduate Training in Physiotherapy (ID: 2022/164401) in December 2022. Eivind Schjelderup Skarpsno is supported by a grant from the Liaison Committee between the Central Norway Regional Health Authority (RHA) and the Norwegian University of Science and Technology (NTNU). Ingebrigt Meisingset is funded by a grant from the Norwegian Research Council (grant number 303331).

    • Competing interests None declared.

    • Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting or dissemination plans of this research. Refer to the Methods section for further details.

    • Provenance and peer review Not commissioned; externally peer reviewed.

    • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.