Defining the impact of improved sleep on cognitive function

ISRCTN ISRCTN89237370
DOI https://doi.org/10.1186/ISRCTN89237370
Secondary identifying numbers N/A
Submission date
11/10/2016
Registration date
17/10/2016
Last edited
01/06/2020
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Mental and Behavioural Disorders
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
Insomnia is a type of sleep disorder which involves an inability to initiate and/or maintain sleep with several daytime consequences, such as extreme tiredness (fatigue), mood disturbances, poor concentration and memory problems. This study is looking at a digital Cognitive Behavioural Therapy (a type of therapy that changes behaviour) for insomnia called Sleepio, in order to find out if it can improve cognition (mental processing) and whether any changes are the result of changes in sleep. To find out whether better sleep improves people’s cognition, participants will be offered an online/mobile phone-delivered course, proven (through previous research) to improve sleep. The aim of this study is to see whether those people who receive this course immediately see any changes in their cognition (specifically their concentration and memory) in comparison to those people who do not receive this treatment and are placed on a wait-list to receive the treatment after a period of 24 weeks.

Who can participate?
Men and women aged 25 and over who complain of insomnia and difficulties with concentration or memory.

What does the study involve?
Participants are randomly allocated into one of two groups. Those in the first group receive the CBT course immediately, delivered using the web and/or mobile phones. The CBT course consists of 6 weekly, tailored sessions with a virtual animated therapist, and access to a range of digital tools (such as an online sleep diary and audio help) and an online community of people who are also working through the programme. Those in the second group are placed on a waiting list and so do not receive any treatment. Both groups complete online surveys and computerised tasks at weeks 0 (start of treatment), 10 (after treatment) and 24 weeks (follow-up). At week 25 all participants allocated to the wait-list control group are offered the CBT course as well. The online surveys measure self-reported cognitive impairment, insomnia severity, fatigue, sleepiness, mood, chronotype (behaviour related to biological clock), sleep medication usage and usage of other sleep treatments. The computerised tasks measure cognitive performance by assessing simple attention, episodic memory (memory of events in the order they happen), working memory (ability to hold on to and mentally manipulate information over short periods of time), visual attention and complex processing speed.

What are the possible benefits and risks of participating?
CBT is likely to be both interesting and helpful to participants. Compensation will also be provided via Amazon vouchers. A voucher code will be emailed upon completion of each assessment point. The amounts will be £5 for the 0-week assessment, £10 for the 10-week assessment and £15 for the 24-week assessment. There are no notable risks associated with participating in this study.

Where is the study run from?
The study is run by the University of Oxford and takes place on the internet (UK)

When is the study starting and how long is it expected to run for?
May 2016 to January 2018

Who is funding the study?
National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (UK)

Who is the main contact?
1. Ms Madeleine Hurry (public)
disco@fmrib.ox.ac.uk
2. Dr Claire Sexton (scientific)
3. Dr Simon Kyle (scientific)

Contact information

Dr Claire Sexton
Scientific

Oxford Centre for Functional MRI of the Brain
John Radcliffe Hospital
Oxford
OX3 9DU
United Kingdom

Dr Simon Kyle
Scientific

Sleep and Circadian Neuroscience Institute
Sir William Dunn School of Pathology
South Parks Road
Oxford
OX1 3RE
United Kingdom

ORCiD logoORCID ID 0000-0002-9581-5311
Ms Madeleine Hurry
Public

Sleep and Circadian Neuroscience Institute
Sir William Dunn School of Pathology
South Parks Road
Oxford
OX1 3RE
United Kingdom

ORCiD logoORCID ID 0000-0003-1060-0328
Phone +44 (0)1865 618668
Email disco@fmrib.ox.ac.uk

Study information

Study designSingle-centre parallel group superiority interventional randomised controlled trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Internet/virtual
Study typeTreatment
Participant information sheet Not available in web format, please use the contact details to request a patient information sheet
Scientific titleDefining the Impact of improved Sleep on COgnitive function: a randomised-controlled trial of digital Cognitive Behavioural Therapy for insomnia versus wait-list control
Study acronymDISCO
Study objectivesPrimary hypothesis:
1. Digital CBT-I will reduce self-reported cognitive impairment at the end of treatment (10 weeks) relative to WLC

Secondary hypotheses:
1. Digital CBT-I will reduce self-reported cognitive impairment at follow-up (24 weeks) relative to WLC
2. The digital CBT intervention will result in improvements in simple attention, visual attention, episodic memory, working memory, and complex processing speed, relative to WLC (10 and 24 weeks)
3. Digital CBT-I will reduce insomnia severity and improve sleep efficiency relative to WLC (10 and 24 weeks)
4. Changes in insomnia (severity and sleep efficiency) at week 10 will mediate change in self-reported cognitive impairment and task performance at week 24
5. Digital CBT-I will lead to improvements in fatigue, sleepiness, self-reported cognitive failures, depression and anxiety relative to WLC (week 10 and 24)
6. Advancing age will be positively associated with treatment-related improvements in self-reported cognitive impairment and objective cognitive performance
Ethics approval(s)Medical Sciences Inter-divisional Research Ethics Committee (IDREC), 28/07/2016, ref: R46116/RE001
Health condition(s) or problem(s) studiedInsomnia disorder
InterventionParticipants are randomised to one of two study groups in a 1:1 ratio using an in-built randomisation feature in the survey software.

Treatment group: Participants recieve digital Cognitive Behavioural Therapy (dCBT) delivered via the Sleepio programme. This comprises of six weekly 30 minute sessions delivered by an animated virtual therapist, plus self-monitoring and report of sleep parameters and mood. In addition to this, participants continue to receive their usual treatment.

Control group: Participants are placed on a waiting list and receive only their usual treatment for 24 weeks. At 25 weeks, participants in this group are given the opportunity to receive the dCBT course.

At 10 and 24 weeks, participants in both groups complete a range of online surveys to assess self-reported cognitive impairment, insomnia severity, fatigue, sleepiness, mood, chronotype, sleep medication usage and usage of other sleep treatments, as well as computerised tasks to measure cognitive performance by assessing simple attention, episodic memory, working memory, visual attention and complex processing speed.
Intervention typeBehavioural
Primary outcome measureSelf-reported cognitive impairment is measured using the British Columbia Cognitive Complaints Inventory (BC-CCI) at baseline, post-treatment (10 weeks) and follow-up (24 weeks)
Secondary outcome measures1. Objective cognitive performance is measured using an online battery of tasks developed by UK Biobank Cognitive Psychology Sub-Group for Cognitive Assessments, including measures of simple attention, episodic memory, working memory, visual attention and complex processing speed at baseline, 10 and 24 weeks
2. Insomnia severity is measued using the Insomnia Severity Index (ISI) and four items from Pittsburgh Sleep Quality Index (PSQI) at baseline, 10 and 24 weeks
3. Fatigue is measured using the Multidimensional Fatigue Inventory (MFI) at baseline, 10 and 24 weeks
4. Sleepiness is measured using the Epworth Sleepiness Scale (ESS) at baseline, 10 and 24 weeks
5. Cognitive failures is measured using the Cognitive Failures Questionnaire (CFQ) at baseline, 10 and 24 weeks
6. Emotional distress (depression and anxiety) will be measured using the Patient Health Questionnaire 9 (PHQ-9) and two items from the Generalised Anxiety Disorder 7 questionnaire (GAD-7) at baseline, 10 and 24 weeks
7. Information on the use of sleep medication will be collected by asking how many nights the participant has used prescribed or non-prescribed medication to aid sleep over the past two weeks at baseline, 10 and 24 weeks

In addition:
8. Additional sleep treatment usage is assessed through asking participants during treatment and follow-up phase
9. Profiling of self-reported chronotype is done using one item from the Morningness-Eveningness Questionnaire (MEQ) at baseline
Overall study start date01/05/2016
Completion date28/01/2018

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participants404
Total final enrolment410
Key inclusion criteria1. Positive screen for probable DSM-5 insomnia disorder using items from the Sleep Condition Indicator (SCI)
2. Endorsement of difficulties with concentration or memory
3. Being aged 25 and above
4. Reliable internet access at home or work
5. Being able to read and understand English
6. Currently living in the UK
Key exclusion criteria1. Additional sleep disorder (e.g. possible obstructive sleep apnoea, restless legs syndrome)
2. Diagnosis of mild cognitive impairment or dementia
3. Psychosis or mania
4. Serious physical health concerns necessitating surgery or with prognosis of <6 months
5. Those undergoing a psychological treatment programme for insomnia with a health professional
6. Habitual night, evening, or rotating shift-workers
7. Those taking prescribed sleeping pills on study entry
8. Those with suicidal ideation

Participants will not be omitted for any other physical or mental health problems providing they report their health to be stable.
Date of first enrolment18/10/2016
Date of final enrolment21/03/2017

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

University of Oxford
Oxford
OX1 3RE
United Kingdom

Sponsor information

University of Oxford
University/education

Research Services
University Offices
Wellington Square
Oxford
OX2 2JD
England
United Kingdom

ROR logo "ROR" https://ror.org/052gg0110

Funders

Funder type

Research organisation

National Institute for Health Research (NIHR) Oxford Biomedical Research Centre

No information available

Results and Publications

Intention to publish date31/12/2019
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryData sharing statement to be made available at a later date
Publication and dissemination planPlanned publication of the results of this study, irrespective of magnitude or direction of effect, in peer-reviewed journals. Findings will also be presented at national and international scientific meetings. The results will be made available online wherever possible, if permitted by journal policies.
IPD sharing planThe current data sharing plans for the current study are unknown and will be made available at a later date.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Protocol article protocol 17/06/2017 Yes No
Results article results 14/09/2020 01/06/2020 Yes No

Editorial Notes

01/06/2020: The following changes have been made:
1. Publication reference added.
2. The final enrolment number has been added from the reference.
19/06/2017: Publication reference added.
25/04/2017: The recruitment end date has been changed from 28/07/2017 to 21/03/2017.