Chronic Low Back Pain (CLBP)SY-NAPS-CSNCT06973837
Studying the Neurobiological Mechanisms of Non-specific Chronic Low Back Pain and Chronic Insomnia: a Four-group Cross-sectional Study
An observational study of Chronic Low Back Pain (CLBP) and Chronic Insomnia, run by Vrije Universiteit Brussel at 1 site in Belgium.
Trial summary
This study is a part of a larger project aiming to evaluate the neurobiological mechanisms underlying the relationship between sleep and pain in people with non-specific chronic low back pain. Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Chronic Low Back Pain (CLBP), Chronic Insomnia, Neuroinflammation
- What is being tested?
- Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.
- How many people
- 80 participants
- Where
- 1 siteBelgium
- Study dates
- 3 Oct 2025to Oct 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Study population: Participants across all study groups will be recruited from the broad area around Leuven, Belgium, via local flyers and social media. Participants with non-specific chronic low back pain and/or chronic insomnia will also be recruited from the pain and/or sleep center of UZ Leuven, Belgium, as well as via primary care units and patient support groups targeting people in the Leuven area. Participants will be recruited and stratified according to sex and age to enable matching to the primary group of interest (chronic low back pain and comorbid insomnia), and a majority of females (~two thirds) will be recruited to better represent the sex-distribution within the population representative of this group.
General inclusion criteria (all groups):
- 18-60 years old.
- Ability to speak and understand the Dutch Language.
- Body mass index <30.
- No smoking or nicotine use.
- Low caffeine use (≤3 cups of coffee/day, ≤1 energy drink/day).
- Low alcohol use (≤9 alcoholic units/week).
- No use of neuro- and/or psychopharmacological treatments and/or immunosuppressive agents (including NSAIDs) with a suspected influence on neuroinflammation unless terminated within a sufficient time frame before the start of the study, or unless falling under the Pharmacological exceptions criteria (see below).
- Willing to (try to) adhere to the acute pre-test restrictions, including refraining from analgesics (unless stable use), caffeine, alcohol, and/or strenuous physical activity (>3 METs) in the 24 hours preceding the main test day.
General exclusion criteria (all groups):
- Shift worker.
- Use of blood thinners.
- (History of) Substance dependence/abuse.
- Chronic pain conditions (≥3 months) other than chronic low back pain.
- Severe intrinsic sleep disorders (assessed during a one-night, laboratory-based polysomnography).
- Restless leg syndrome
- Central or peripheral neurological disorder/condition (e.g., epilepsy, multiple sclerosis, peripheral neuropathy).
- History of spinal surgery.
- Major medical (e.g., cardiac disease, cancer) and/or psychiatric disorder/disease (e.g., major depressive disorder, bipolar disorder).
- Claustrophobia.
- Contraindications for magnetic resonance imaging (e.g., metal/cochlear implants, pacemaker).
- Pregnancy or being <12 months post-natal.
Pharmacological exceptions criteria:
- Participants with chronic low back pain and/or (comorbid) insomnia will be allowed to be on a stable low dose of weak pain and/or sleep agents (e.g., Tramadol, Zolpidem) if medically prescribed specifically for their low back pain and/or insomnia, and if approved by the national medicine register of Belgium (FAMHP, Federal Agency for Medicine and Health Products). These participants will also be allowed stable and/or occasional use of low-to-moderate doses of over-the-counter medications for pain and/or sleep that are suspected to have no or minimal impact on neuroinflammation (e.g., paracetamol, melatonin). Habitual use of medications according to the above-stated criteria should be maintained across the entire study period, with the only exception being analgesics taken on an occasional basis. Specifically, because of the extensive battery of pain tests that will be utilized in the study, all analgesics that are only taken occasionally should be refrained from during the 24 hours preceding the main test day (pre-test instructions).
Specific inclusion criteria for "pain-free" groups:
- Currently pain free, defined as having no pain that affects daily living/functioning and/or which has led to a consultation with a healthcare practitioner.
- No episode of low back pain that interfered with daily functioning/living and/or which led to a consultation with a healthcare practitioner within 12 months from the time of inclusion.
- No history of chronic low back pain.
Specific inclusion criteria for "chronic low back pain" groups:
- Low back pain reported on most days (≥50%), every week, for more than 3 months.
- Low back pain-related emotional disress OR functional disability rated as ≥3 out of 10.
Specific inclusion criteria for "good sleeper" groups:
- Stable sleep phase within 10 PM and 10 AM (assessed using the Pittsburgh Sleep Quality Index).
- Average habitual total sleep time between 7 and 9 hours (assessed using the Pittsburgh Sleep Quality Index).
- A Pittsburgh Sleep Quality Index ≤5.
- An Insomnia Severity Index ≤7.
- An Epworth Sleepiness Scale ≤10.
- Sleep efficiency ≥85% during a one-night, laboratory-based polysomnography screening.
- No episode of sleep disturbances that interfered with daily functioning/living and/or which led to a consultation with a healthcare practitioner within the preceding 12 months from the time of inclusion.
- No history of chronic insomnia.
Specific inclusion criteria for "chronic insomnia" groups:
- Chronic insomnia according to the ICSD-3-TR criteria (assessed using an ICSD-3-TR-adapted version of the Pittsburgh Sleep Quality Index).
- An Insomnia Severity Index ≥15.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Belgium1 site, 1 recruiting
- Recruiting
UZ/KU Leuven
Leuven, 3000
Iris Coppieters, PT, PhD, +324 97 92 90 32, iris.coppieters@vub.be
Elin Johansson, PT, PhD, +46 702 05 54 52, elinmarie.johansson@kuleuven.be
About this study
Official title: Unravelling the Neurobiological Mechanisms Underlying the Bidirectional Relationship Between Chronic Sleep Disturbances and Pain Sensitivity in People With Non-specific Chronic Low Back Pain and Chronic Insomnia
This study is a part of a larger project aiming to evaluate the neurobiological mechanisms underlying the relationship between sleep and pain in people with non-specific chronic low back pain. Specifically, this study aims to evaluate the neurobiological mechanisms underlying the relationship between chronic sleep disturbances and pain sensitivity in people with non-specific chronic low back pain and chronic insomnia.
Read the detailed description
Sleep disturbances, and especially insomnia, reflect one of the most common comorbidities in people with chronic pain, including people with chronic low back pain. Previous research has furthermore demonstrated that a lack of sleep is associated with an increased pain sensitivity. The goal of this study is to evaluate the role of brain neuroinflammation in the relationship between chronic sleep disturbances and both clinical and experimental pain sensitivity in people non-specific chronic low back pain and/or chronic insomnia.
A cross-sectional study will be conducted across four age- and sex-matched study groups: healthy controls with good sleep habits (Group 1); people with non-specific chronic low back pain and good sleep habits (Group 2); pain-free individuals with chronic insomnia (Group 3); and people with non-specific chronic low back pain and comorbid chronic insomnia (Group 4). The study will be performed over nine consecutive days. All participants will arrive at the lab at a standardized time, relative to their habitual bedtime, in the afternoon of the first study day. There, they will first fill out a number of baseline questionnaires, after which a battery of quantitative sensory test, utilizing both manual and computerized pressure algometry, will be performed to assess experimental pain sensitivity. After being provided a standardized dinner, the participants will then perform a clinical polysomnography (i.e., sleep study) during an over-night stay at the hospital sleep center (UZ Leuven, Belgium) to acquire data on sleep time, stability, and efficiency, as well as to identify participants with combined sleep-disorder-comorbidity profiles (e.g. insomnia + apnea). Directly upon awakening in the morning of the second day, all participants will first fill in a few additional questionnaires, and then be provided a standardized low-fiber breakfast alongside a bolus of pure fiber. Next, the participants will be escorted to the magnetic resonance imaging facility and perform two blocks of brain scanning separated by an approximate 10-min break. During the first block, magnetic resonance spectroscopy and diffusion-weighted magnetic resonance imaging will be performed to measure markers of neuroinflammation, whereas the second block utilizes functional magnetic resonance imaging during an evoked-low-back-pain task to acquire data on back pain-evoked brain activity. After the two scanning blocks, the second study day ends by the collection of a venous blood sample to assess systemic levels of inflammation (via highly sensitive C-reactive protein) and short chain fatty acids. During the following seven days, all participants will complete a sleep diary once per day, provide momentary ratings of pain, sleepiness, fatigue, and affect eight times per day, and wear an Actigraph at all times (except during heavy water contact). During this seven-day period, the participants will also be instructed to collect a stool sample at a time of their own convenience, but preferably within the first three days, to be used for gut microbiota composition analyses. Continuous dietary intake will therefore also be recorded during the first three days of the seven-day period, while participants who are not able to collect their stool sample during any of these three days will continue to record their dietary intake until a stool sample has been collected.
- Being tested
- Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.
- Keywords
- Pain, Chronic pain, Chronic low back pain, Sleep, Insomnia, Chronic insomnia, Magnetic resonance imaging, Functional magnetic resonance imaging, Magnetic resonance spectroscopy, Diffusion weighted imaging, Quantitative sensory testing, Temporal summation, Conditioned pain modulation, Experience sampling method, Ecological momentary assessment, Microbiota, Gut-Brain axis, Short-chain fatty acids
- Medical subject headings
- Sleep Initiation and Maintenance Disorders, Neuroinflammatory Diseases, Pain, Chronic Pain
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.Other
See detailed study description and outcome measures.
| Study group | Role | What they receive |
|---|---|---|
| Pain-free with good sleep habits (healthy controls) | Meeting all General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "pain-free" and "good sleeper". Receives: Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling. | |
| Non-specific chronic low back pain with good sleep habits | Meeting all General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "chronic low back pain" and "good sleeper". Receives: Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling. | |
| Pain-free with chronic insomnia | Meeting General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "pain-free" and "chronic insomnia". Receives: Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling. | |
| Non-specific chronic low back pain with comorbid chronic insomnia | Meeting all General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "chronic low back pain" and "chronic insomnia". Receives: Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Brain metabolite concentrations
Concentration of brain metabolites measured using single-voxel magnetic resonance spectroscopy in five regions of interest: (1) pregenual anterior cingulate cortex (midline); (2/3) right/left thalamus; (4/5) right/left anterior insula.
Measured: Day 2
Secondary outcomes (20)
Brain-tissue microstructure diffusivity
Diffusivity data (diffusion-weighted signal) from different microstructural compartments within the brain (intra-axonal space, extra-axonal space, and free water) measured using diffusion-weighted magnetic resonance imaging.
Measured: Day 2
Functional brain responses to evoked low back pain
Blood-oxygen-level-dependent (BOLD) signal acquired during an evoked low back pain task performed during functional magnetic resonance imaging sequence.
Measured: Day 2
Manual pressure pain detection thresholds (mPDT)
Gradually increasing pressure (1 kgf/sec) applied using a manual pressure algometer (FPX50, Wagner Instruments, USA) until the first sensation of discomfort (mPDT) is (self-)reported. The measurement is repeated three times across six body sites: (1/2) right/left m. erector spinae; (3/4) right/left m. extensor carpi radialis; (5/6) right/left m. gastrocnemius.
Measured: Day 1
Computerized pressure pain detection thresholds (cPDT)
Gradually increasing pressure (1 kPa/sec) applied via a computer-controlled blood pressure cuff (Nocitech, Aalborg University, Denmark) around the calf (dominant leg) until a first sensation of discomfort (cPDT) is rated.
Measured: Day 1
Computerized pressure pain tolerance thresholds (cPTT)
Gradually increasing pressure (1 kPa/sec) applied via a computer-controlled blood pressure cuff (Nocitech, Aalborg University, Denmark) around the calf (dominant leg) until it is no longer tolerable.
Measured: Day 1
Temporal summation of (pressure) pain
Twelve repeated pressure stimuli (stimulus duration: 1 sec; interstimulus interval: 1 sec) applied via a computer-controlled blood pressure cuff (Nocitech, Aalborg University, Denmark) around the calf (dominant leg) at an intensity corresponding to the cPTT.
Measured: Day 1
Conditioned (pressure) pain modulation
One cPTT assessment via computer-controlled blood pressure cuff algometry (Nocitech, Aalborg University, Denmark) performed immediately before and after a 1-min hot water immersion of the hand contralateral to the stimulated calf (dominant leg).
Measured: Day 1
Daily self-reported pain distribution assessed via experience sampling methodology (m-Path smartphone application)
A list of body regions from which participants select the regions at which they experience pain "right now", assessed at eight block-randomized time points per day.
Measured: Day 3 to 9
Daily self-reported low back pain (fluctuations) assessed via experience sampling methodology (m-Path smartphone application)
Intensity, unpleasantness, and attention to low back pain "right now" rated on a 0-to-100 visual analogue scale at eight block-randomized time points per day.
Measured: Day 3 to 9
Daily self-reported affect (fluctuations) assessed via experience sampling methodology (m-Path smartphone application)
Positive and negative affect "right now" rated on a 0-to-100 visual analogue scale at eight block-randomized time points per day.
Measured: Day 3 to 9
Daily self-reported fatigue (fluctuations) assessed via experience sampling methodology (m-Path smartphone application)
Mental and physical fatigue "right now" rated on a 0-to-100 visual analogue scale at eight block-randomized time points per day.
Measured: Day 3 to 9
Daily self-reported sleepiness (fluctuations) assessed via the Karolinska Sleepiness Scale (KSS) implemented into the experience sampling methodology smartphone application (m-Path)
The KSS is a single-item questionnaire (i.e., scale) that measures subjective sleepiness at a specific moment in time. Scores range from 1 to 9, with higher scores indicating greater sleepiness. The scale was completed at eight block-randomized time points per day.
Measured: Day 3 to 9
Daily sleep-wake cycles assessed by Actigraphy
Wrist-worn actigraphy (GT3X Actigraph, Pensacola, FL, USA) at all times except heavy water contact.
Measured: Day 3 to 9
Daily self-reported perceived sleep duration assessed via sleep diaries
Subjective time points for when getting into and out of bed, and for sleep onset and offset, provided once per day.
Measured: Day 3 to 9
Daily self-reported nighttime pain assessed via sleep diaries
Pain intensity during the preceding night, rated on a 0-to-10 numerical rating scale once per day.
Measured: Day 3 to 9
Daily self-reported subjective sleep quality assessed via sleep diaries
Subjective sleep quality from the preceding night, rated on a 0-to-10 numerical rating scale once per day.
Measured: Day 3 to 9
Daily self-reported subjective wake quality assessed via sleep diaries
Subjective wake quality during the day, rated on a 0-to-10 numerical rating scale once per day.
Measured: Day 3 to 9
Serum short chain fatty acid levels
Levels of short chain fatty acids analysed from serum aliquots derived from venous blood samples.
Measured: Day 2
Microbiota composition
Composition-related outcomes (e.g., diversity, abundance) analysed from stool-sample aliquots.
Measured: At one single occasion at any day between Day 3 to 9
Habitual self-reported macronutrient intake (including fibre) assessed via continuous dietary records (MyFitnessPal smartphone application)
Macronutrient and fibre intake (in grams) estimated (via MyFitnessPal application) from continuous self-reported dietary intake (food diary).
Measured: From Day 3 to at least Day 5, but up to Day 9 depending on the day at which a stool sample is collected
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 May 2025
- Study start3 Oct 2025
- Primary completionOct 2026 (estimated)
- Study completionOct 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Chronic Low Back Pain (CLBP)Studies of the same condition, open and under way.
- More trials run by Vrije Universiteit BrusselThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Vrije Universiteit Brussel
- Sponsor type
- University, hospital or other
- Collaborators
- Research Foundation - Flanders (Fonds Wetenschappelijk Onderzoek), Universitaire Ziekenhuizen KU Leuven
- Responsible party
- Principal investigator, Iris Coppieters, Vrije Universiteit Brussel
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06973837
- Sponsor's protocol ID
- 11PMF24N
- Other IDs
- G080423N, S68780
- Acronym
- SY-NAPS-CS
- Status last verified
- Dec 2025
- First submitted
- 5 May 2025
- Last updated
- 15 Dec 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Individual participant data (IPD) that underlie results in a publication will be made available to other researchers with all identifying information removed.
Study at a glance
From the registry record, last updated by the sponsor on 15 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Unravelling the Neurobiological Mechanisms Underlying the Bidirectional Relationship Between Chronic Sleep Disturbances and Pain Sensitivity in People With Non-specific Chronic Low Back Pain and Chronic Insomnia
- ClinicalTrials.gov ID
- NCT06973837
- Acronym / sponsor ID
- SY-NAPS-CS / 11PMF24N
- Keywords
- Pain, Chronic pain, Chronic low back pain, Sleep, Insomnia, Chronic insomnia, Magnetic resonance imaging, Functional magnetic resonance imaging
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- Vrije Universiteit BrusselUniversity, hospital or other
- Collaborators
- Research Foundation - Flanders (Fonds Wetenschappelijk Onderzoek), Universitaire Ziekenhuizen KU Leuven
- Study start
- 3 Oct 2025 (actual)
- Primary completion
- Oct 2026 (estimated)
- Study completion
- Oct 2026 (estimated)
- First posted
- 15 May 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study is a part of a larger project aiming to evaluate the neurobiological mechanisms underlying the relationship between sleep and pain in people with non-specific chronic low back pain. Specifically, this study aims to evaluate the neurobiological mechanisms underlying the relationship between chronic sleep disturbances and pain sensitivity in people with non-specific chronic low back pain and chronic insomnia.
Detailed description
Sleep disturbances, and especially insomnia, reflect one of the most common comorbidities in people with chronic pain, including people with chronic low back pain. Previous research has furthermore demonstrated that a lack of sleep is associated with an increased pain sensitivity. The goal of this study is to evaluate the role of brain neuroinflammation in the relationship between chronic sleep disturbances and both clinical and experimental pain sensitivity in people non-specific chronic low back pain and/or chronic insomnia.
A cross-sectional study will be conducted across four age- and sex-matched study groups: healthy controls with good sleep habits (Group 1); people with non-specific chronic low back pain and good sleep habits (Group 2); pain-free individuals with chronic insomnia (Group 3); and people with non-specific chronic low back pain and comorbid chronic insomnia (Group 4). The study will be performed over nine consecutive days. All participants will arrive at the lab at a standardized time, relative to their habitual bedtime, in the afternoon of the first study day. There, they will first fill out a number of baseline questionnaires, after which a battery of quantitative sensory test, utilizing both manual and computerized pressure algometry, will be performed to assess experimental pain sensitivity. After being provided a standardized dinner, the participants will then perform a clinical polysomnography (i.e., sleep study) during an over-night stay at the hospital sleep center (UZ Leuven, Belgium) to acquire data on sleep time, stability, and efficiency, as well as to identify participants with combined sleep-disorder-comorbidity profiles (e.g. insomnia + apnea). Directly upon awakening in the morning of the second day, all participants will first fill in a few additional questionnaires, and then be provided a standardized low-fiber breakfast alongside a bolus of pure fiber. Next, the participants will be escorted to the magnetic resonance imaging facility and perform two blocks of brain scanning separated by an approximate 10-min break. During the first block, magnetic resonance spectroscopy and diffusion-weighted magnetic resonance imaging will be performed to measure markers of neuroinflammation, whereas the second block utilizes functional magnetic resonance imaging during an evoked-low-back-pain task to acquire data on back pain-evoked brain activity. After the two scanning blocks, the second study day ends by the collection of a venous blood sample to assess systemic levels of inflammation (via highly sensitive C-reactive protein) and short chain fatty acids. During the following seven days, all participants will complete a sleep diary once per day, provide momentary ratings of pain, sleepiness, fatigue, and affect eight times per day, and wear an Actigraph at all times (except during heavy water contact). During this seven-day period, the participants will also be instructed to collect a stool sample at a time of their own convenience, but preferably within the first three days, to be used for gut microbiota composition analyses. Continuous dietary intake will therefore also be recorded during the first three days of the seven-day period, while participants who are not able to collect their stool sample during any of these three days will continue to record their dietary intake until a stool sample has been collected.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Pain-free with good sleep habits (healthy controls) | – | Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.Meeting all General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "pain-free" and "good sleeper". |
| Non-specific chronic low back pain with good sleep habits | – | Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.Meeting all General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "chronic low back pain" and "good sleeper". |
| Pain-free with chronic insomnia | – | Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.Meeting General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "pain-free" and "chronic insomnia". |
| Non-specific chronic low back pain with comorbid chronic insomnia | – | Other: Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.Meeting all General inclusion/exclusion criteria and Pharmacological exceptions criteria, plus the specific inclusion criteria for "chronic low back pain" and "chronic insomnia". |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- Participants across all study groups will be recruited from the broad area around Leuven, Belgium, via local flyers and social media. Participants with non-specific chronic low back pain and/or chronic insomnia will also be recruited from the pain and/or sleep center of UZ Leuven, Belgium, as well as via primary care units and patient support groups targeting people in the Leuven area. Participants will be recruited and stratified according to sex and age to enable matching to the primary group of interest (chronic low back pain and comorbid insomnia), and a majority of females (~two thirds) will be recruited to better represent the sex-distribution within the population representative of this group.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Real-life monitoring, experimental pain testing, brain imaging, blood and stool sampling.See detailed study description and outcome measures. | Other | Non-specific chronic low back pain with comorbid chronic insomnia, Non-specific chronic low back pain with good sleep habits, Pain-free with chronic insomnia, Pain-free with good sleep habits (healthy controls) |
Primary outcome
Brain metabolite concentrations
Time frame: Day 2
Concentration of brain metabolites measured using single-voxel magnetic resonance spectroscopy in five regions of interest: (1) pregenual anterior cingulate cortex (midline); (2/3) right/left thalamus; (4/5) right/left anterior insula.
20 secondary outcomes
Brain-tissue microstructure diffusivity
Time frame: Day 2
Functional brain responses to evoked low back pain
Time frame: Day 2
Manual pressure pain detection thresholds (mPDT)
Time frame: Day 1
Computerized pressure pain detection thresholds (cPDT)
Time frame: Day 1
Computerized pressure pain tolerance thresholds (cPTT)
Time frame: Day 1
Temporal summation of (pressure) pain
Time frame: Day 1
Conditioned (pressure) pain modulation
Time frame: Day 1
Daily self-reported pain distribution assessed via experience sampling methodology (m-Path smartphone application)
Time frame: Day 3 to 9
Daily self-reported low back pain (fluctuations) assessed via experience sampling methodology (m-Path smartphone application)
Time frame: Day 3 to 9
Daily self-reported affect (fluctuations) assessed via experience sampling methodology (m-Path smartphone application)
Time frame: Day 3 to 9
Daily self-reported fatigue (fluctuations) assessed via experience sampling methodology (m-Path smartphone application)
Time frame: Day 3 to 9
Daily self-reported sleepiness (fluctuations) assessed via the Karolinska Sleepiness Scale (KSS) implemented into the experience sampling methodology smartphone application (m-Path)
Time frame: Day 3 to 9
Daily sleep-wake cycles assessed by Actigraphy
Time frame: Day 3 to 9
Daily self-reported perceived sleep duration assessed via sleep diaries
Time frame: Day 3 to 9
Daily self-reported nighttime pain assessed via sleep diaries
Time frame: Day 3 to 9
Daily self-reported subjective sleep quality assessed via sleep diaries
Time frame: Day 3 to 9
Daily self-reported subjective wake quality assessed via sleep diaries
Time frame: Day 3 to 9
Serum short chain fatty acid levels
Time frame: Day 2
Microbiota composition
Time frame: At one single occasion at any day between Day 3 to 9
Habitual self-reported macronutrient intake (including fibre) assessed via continuous dietary records (MyFitnessPal smartphone application)
Time frame: From Day 3 to at least Day 5, but up to Day 9 depending on the day at which a stool sample is collected
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Dec 2025.
- Individual participant dataSharing planned: Yes. Individual participant data (IPD) that underlie results in a publication will be made available to other researchers with all identifying information removed.
Related trials for Chronic Low Back Pain (CLBP)
Not yet recruiting
Comparing Non-Medicine Strategies for Improving Low Back Pain
Chronic Low-back Pain (cLBP), High-Impact Chronic Pain (HICP)
Not yet recruiting
Spinery Basivertebral Nerve Ablation for Vertebrogenic Chronic Low Back Pain
Low Back Pain, Chronic Low Back Pain (CLBP)
Recruiting
SENECA - Smart Therapies for Chronic Pain
Chronic Low Back Pain (CLBP)
Not yet recruiting
Comparison of Two Patient Education Methods in Women With Chronic Low Back Pain: Online Pain Education vs. AI-Driven Patient Education on Pain Beliefs, Catastrophizing, and Self-Efficacy
Chronic Low Back Pain (CLBP)
Not yet recruiting
Effects of Myofascial Techniques on Chronic Low Back Pain
Chronic Low-back Pain (cLBP)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Chronic Low Back Pain (CLBP) and Chronic Insomnia, run by Vrije Universiteit Brussel at 1 site in Belgium.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 15 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Iris Coppieters, PT, PhD (+32 497 92 90 32, iris.coppieters@vub.be), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Brain metabolite concentrations (time frame: Day 2). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 Dec 2025.