Hyperventilation in Patients With Chronic Low Back Pain

Study Overview
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Brief Summary
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Low back pain (LBP) is the leading cause of disability worldwide. Impaired postural control is a key factor in the development and maintenance of LBP. Moreover, the prevalence of LBP is associated with impairments in diaphragm function, symptoms of dyspnea, and dysfunctional breathing. However, the association between LBP (and more specifically postural control) and hyperventilation remains unknown. The main objective of this project is to investigate whether the presence of recurrent non-specific LBP is related to the presence of hyperventilation, when classified either objectively by decreased carbon dioxide values (demonstrating hypocapnia) or by symptoms while showing normal carbon dioxide values. Moreover, the investigators will explore whether psychosocial factors play a role in this relation. Subsequently, the investigators will examine whether hyperventilation in LBP patients is related to impaired postural control, and more specifically to a decreased postural contribution of the diaphragm.

Official Title
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Hyperventilation in Patients With Chronic Low Back Pain

Conditions
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Low Back Pain, Recurrent, Hyperventilation Syndrome

Intervention / Treatment
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* Behavioral: assessment of hyperventilation, postural control and psychological behavior


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Patients: Chronic primary low back pain (>12 weeks) as diagnosed by a medical doctor Inclusion Criteria Healthy controls: No low back pain Exclusion Criteria: Insufficient understanding of Dutch language Previous spinal surgery Chronic Obstructive Lung Disease, Interstitial Lung Disease, pulmonary vascular disease, asthma except for exertional asthma Acute cardiovascular or gastrointestinal disorders Neuromuscular disease interfering with normal lower limb or trunk functioning Acute pain or secondary chronic pain Pregnant and lactating women Major psychiatric conditions Acute lower limb problems Vestibular disorders

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Patients with low back pain are compared to patients without low back pain (healthy controls).
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Patients with low back pain<br> | Behavioral: assessment of hyperventilation, postural control and psychological behavior<br>* assessment of hyperventilation, postural control and psychological behavior<br>|
| Sham Comparator: Healthy controls<br> | Behavioral: assessment of hyperventilation, postural control and psychological behavior<br>* assessment of hyperventilation, postural control and psychological behavior<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Nijmegen questionnaire | Questionnaire evaluating hyperventilation symptoms, 16 items, total score range 0-64 | Day 1 | 
| Nijmegen questionnaire | Questionnaire evaluating hyperventilation symptoms, 16 items, total score range 0-64 | Day 4 | 
| PetCO2 | End-tidal carbon dioxide pressure measured with a capnograph | Day 1 | 
| Postural control | upright standing balance measured by center of pressure by force plate | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Breathing frequency | amount of breaths per minute, inspiratory and expiratory time | Day 1 | 
| Breathing pattern (abominal and thoracic) | abdominal or thoracic contribution to one breath measured by respiratory inductance plethysmography | Day 1 | 
| Numerical Rating Scale for low back pain (NRS) | 11 point Likert scale evaluating severity/intensity of back pain, ranging from 0 (no pain) to 11 (worst pain imaginable) | Day 1 | 
| Oswestry Disability Index version 2.1a (ODI-2.1a) | Questionnaire evaluating disability. 10 items Total score range from 0-100 | Day 1 | 
| 12-item Short form Health Survey (SF-12) | Questionnaire evaluating physical and mental components of health related quality of life. 12 items. Total score range 12-56. | Day 1 | 
| Fear Avoidance Component Scale (FACS) | Questionnaire evaluating fear-avoidance related to pain. 20 items Total score range from 0-100 | Day 1 | 
| Tampa Scale for Kinesiophobia (TSK) | Questionnaire evaluating kinesiophobia related to pain. 17 items. Total score range from 17-68 | Day 1 | 
| Pain Catastrophizing Scale (PCS) | Questionnaire evaluating catastrophizing. 13 items, 5 point Likert scale. Total score 0-52 | Day 1 | 
| Need for Controllability and Predictability Questionnaire (NCP-Q) | Questionnaire evaluating the need for being able to control and predict situations. 15 items, 5 point Likert scale. Total score range 15 - 75 | Day 1 | 
| Positive And Negative Affect Schedule (PANAS) | Questionnaire evaluating positive and negative affect. 10 items positive affect, 10 items negative affect, 5 point Likert scale. Total score range per affect: 10 - 50 | Day 1 | 
| Pain Solutions Questionnaire (PaSoL) | Questionnaire evaluating assimilative and accommodative responses to problems associated with pain. 14 items, 7 point Likert scale. Total score range 0 - 84 | Day 1 | 
| Toronto Alexithymia Scale 20 (TAS-20) | Questionnaire evaluating characteristics linked to alexithymia. 20 items, 3 factors. Total score range 20 - 100 | Day 1 | 
| Interoceptive Awareness Questionnaire (IAQ) | Questionnaire evaluating adaptive and maladaptive body awareness. 19 items, 5 point Likert scale. | Day 1 | 
| Fremantle Back Awareness Questionnaire (FreBAQ) | Questionnaire evaluating back specific perceptual awareness. 9 items, 5 point Likert scale. Total score range 0-36 | Day 1 | 
| Vragenlijst belastende ervaringen (VBE) - short version | Questionnaire evaluating aversive experiences in adult life. 11 items should be scored with yes or no. If yes a score on a 5 point Likert scale should be given. | Day 1 | 
| Multidimensional Perfectionism Scale (MPS) | Questionnaire evaluating adaptive and maladaptive perfectionism. 35 items, 5 point Likert scale. Total score range 35 - 175 | Day 1 | 
| International Physical Activity Questionnaire - Short Form (IPAQ-SF) | Questionnaire evaluating subjective level of physical activity. 7 questions regarding amount of time spent on certain activities. | Day 1 |