Diffuse Noxious Inhibitory Controls (DNIC): Nociceptive Modulation and Interaction With Neurocognitive Performance in Chronic Pain

Chronic Pain Clinical Trial

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT01172795
• Other study ID #: B-Cognitive tests
• Status: Recruiting
• Phase: N/A
• First received: July 29, 2010
• Last updated: July 29, 2010
• Start date: July 2010
• Est. completion date: August 2011

Study information

• Verified date: July 2010
• Source: Vrije Universiteit Brussel
• Contact: Mira Meeus, PhD
• Phone: 0032 485 58 21 14
• Email: mmeeus[@]vub.ac.be
• Is FDA regulated: No
• Health authority: Belgium: Ethics Committee
• Study type: Observational

Clinical Trial Summary

Diffuse noxious inhibitory control In order to quantify central sensitization in chronic pain patients, the Diffuse Noxious Inhibitory Control (DNIC) model has been used frequently. DNIC relies on painful conditioning stimulation of one part of the body to inhibit pain in another part, to remove the "noise" and to focus on relevant stimuli.

Earlier studies provided evidence for malfunctioning of DNIC in Fibromyalgia (FM) patients. However, the cause of this impairment is not yet elucidated, and further study is required to unravel the pathophysiology of DNIC in FM.

Hypothalamus-Pituitary-Adrenal (HPA) axis Besides neural mechanisms, also hormonal abnormalities could cause altered pain processing. Cortisol is released in answer to pain to suppress the pain. Given the evidence for hypofunction of the hypothalamic-pituitary-adrenal axis and the lower cortisol release in response to stressors in a proportion of FM patients and in chronic whiplash associated disorders (WAD) patients, the relation between pain and cortisol in these patients may be an interesting topic to consider.

Neurocognitive performance Besides chronic pain, people with chronic WAD and FM suffer from severe concentration difficulties and decreased neurocognitive capabilities (reduced reaction time, short term memory deficits etc. The decreased neurocognitive performance is known to be related to pain severity in various chronic pain populations. It is hypothesized that malfunctioning of descending inhibitory pathways and subsequent chronic pain experience precludes optimal neurocognitive performance.

Objectives The present investigation addresses the (patho)physiological mechanisms of DNIC in chronic pain populations.

1. Firstly, patients with FM, chronic WAD and healthy controls are compared regarding functioning of DNIC, cortisol levels and response and neurocognitive performance (case-control).

2. Secondly, the possible interaction between the functioning of DNIC, cortisol and neurocognitive performance is studied in patients with FM, WAD and healthy control subjects (cross-sectional).

3. Thirdly, to examine whether a fatiguing neurocognitive stressor changes DNIC and cortisol levels in patients with FM, chronic WAD or healthy sedentary control subjects.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 100
• Est. completion date: August 2011
• Est. primary completion date: July 2011
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 65 Years

Eligibility

Inclusion Criteria:

• 30 FM group: comply with the diagnostic criteria for FM as defined by the American College of Rheumatology.

• 30 WAD group: comply with the criteria of the Quebec Task Force (grade I to III)

• 40 healthy pain-free control subjects

• Dutch speaking

• aged between 18 and 65 years.

Exclusion Criteria:

• FM patients reporting a history of a whiplash trauma

• WAD patients fulfilling the diagnostic criteria for FM

• healthy control subjects cannot suffer any pain complaints

• cannot be pregnant or until 1 year postnatal

• asked to stop analgesics 48 hours prior to study participation, not to undertake physical exertion, and to refrain from consuming caffeine, alcohol or nicotine on the day of the experiment.

Study Design

Observational Model: Case-Crossover, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Chronic Pain
• Fibromyalgia
• Whiplash

Intervention

Behavioral:
• Relaxation session
30 minutes relaxation session (audiotape)
• Neurocognitive test battery
the psychomotor vigilance task, span task and the stroop task on computer

Locations

Country	Name	City	State
Belgium	Vrije Universiteit Brussel	Brussels

Sponsors (2)

Lead Sponsor	Collaborator
Vrije Universiteit Brussel	Research Foundation Flanders

Country where clinical trial is conducted

Belgium, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	pain inhibition efficacy	Participants are subjected to pain measurement, preceded and followed by the collection of saliva samples to analyze cortisol concentrations. Afterwards participants are randomly (by lottery) allocated to group 1 or 2. Group 1 performs a battery of neurocognitive tests and group 2 receives a relaxation session. Afterwards pain measurement with cortisol analyses is repeated.; One week later the procedure is repeated, while group 1 receives the relaxation session and group 2 performs the neurocognitive test.	immediately (5 minutes) before and after intervention (relaxation or neurocognitive test battery)	No
Secondary	neurocognitive performance	Participants are subjected to pain measurement, preceded and followed by the collection of saliva samples to analyze cortisol concentrations. Afterwards participants are randomly (by lottery) allocated to group 1 or 2. Group 1 performs a battery of neurocognitive tests and group 2 receives a relaxation session. Afterwards pain measurement with cortisol analyses is repeated.; One week later the procedure is repeated, while group 1 receives the relaxation session and group 2 performs the neurocognitive test.	once in the study design, immediately (5 minutes) preceded and followed by the pain measurements	No
Secondary	cortisol response to pain	Participants are subjected to pain measurement, preceded and followed by the collection of saliva samples to analyze cortisol concentrations. Afterwards participants are randomly (by lottery) allocated to group 1 or 2. Group 1 performs a battery of neurocognitive tests and group 2 receives a relaxation session. Afterwards pain measurement with cortisol analyses is repeated.; One week later the procedure is repeated, while group 1 receives the relaxation session and group 2 performs the neurocognitive test.	immediately (1 minute) before and after pain measurements	No