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Diaphragmatic Function as a Biomarker

Recruiting
Conditions
Fibrosis
Dyspnea; Asthmatic
Pulmonary Hypertension
Dyspnea
COPD
Asthma
Interventions
Diagnostic Test: Diaphragm Ultrasound
Diagnostic Test: Intercostal Muscle Ultrasound
Diagnostic Test: Borg scale
Diagnostic Test: MRC Breathlessness Scale
Diagnostic Test: Respiratory Questionaire
Diagnostic Test: GINA classification of Asthma
Diagnostic Test: Measurement of respiratory mouth pressure
Diagnostic Test: SNIP
Diagnostic Test: 6-minute walking distance
Diagnostic Test: Electromyography
Diagnostic Test: 60 seconds sit-to-stand test
Diagnostic Test: Lung Function
Diagnostic Test: CAT-Questionnaire
Diagnostic Test: European Society of Cardiology (ESC)/ European Respiratory Society (ERS) risk group
Registration Number
NCT05903001
Lead Sponsor
RWTH Aachen University
Brief Summary

Dyspnea is among the most common symptoms in patients with respiratory diseases such as Asthma, chronic obstructive pulmonary disease (COPD), Fibrosis, and Pulmonary Hypertension. However, the pathophysiology and underlying mechanisms of dyspnea in patients with respiratory diseases are still poorly understood. Diaphragm dysfunction might be highly prevalent in patients with dyspnea and respiratory diseases. The association of diaphragm function and potential prognostic significance in patients with respiratory diseases has not yet been investigated.

Detailed Description

The aim of the present project is to comprehensively measure respiratory muscle function and strength in patients with respiratory diseases. The investigators attempt to recruit 800 patients across four disease groups (Asthma, COPD, Fibrosis, and Pulmonary Hypertension) and the investigators intend to measure diaphragm and accessory respiratory muscle function and strength, lung function, and exercise tolerance, as well as the participants' symptom burden during one day at baseline in the investigators' lab. Thereafter, the investigators will follow up on patients by phone 3 months, 6 months, 12 months and 18 months after the investigators have seen them in the investigators' lab. Based on these results, not only the association between dyspnea exercise tolerance and diaphragm function in patients with respiratory diseases can be assessed, but also the prognostic significance of diaphragm dysfunction in these patients can be determined. As such, hospitalization and exacerbation requiring the intake of steroids will be assessed and followed up on by phone, and therefore the prognostic significance of diaphragm dysfunction in predicting hospitalization and the intake of steroids can be determined.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
800
Inclusion Criteria
  • patient has one of the following lung diseases: COPD, bronchial asthma, pulmonary fibrosis, pulmonary hypertension
  • is 18 years or older
  • is mentally and physically able to understand the study and to follow instructions
  • are legally competent
  • signed declaration of consent
Exclusion Criteria
  • BMI > 35
  • current or treatments or diseases in the past which could influence the evaluation of the study
  • Expected lack of willingness to actively participate in study-related measures
  • alcohol or drug abuse
  • disc herniation/prolapse
  • epilepsy
  • wheelchair bound
  • in custody due to an official or court order
  • in a dependent relationship or employment relationship with investigating physician or one of their deputy
  • emergency inpatient hospital stay within 4 weeks before study-specific examinations

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Patients with FibrosisBorg scale-
Patients with FibrosisLung Function-
Patients with AsthmaGINA classification of Asthma-
Patients with COPDDiaphragm Ultrasound-
Patients with COPDIntercostal Muscle Ultrasound-
Patients with FibrosisIntercostal Muscle Ultrasound-
Patients with FibrosisMRC Breathlessness Scale-
Patients with FibrosisElectromyography-
Patients with Pulmonary HypertensionBorg scale-
Patients with Pulmonary HypertensionMRC Breathlessness Scale-
Patients with AsthmaDiaphragm Ultrasound-
Patients with AsthmaBorg scale-
Patients with Asthma6-minute walking distance-
Patients with COPD6-minute walking distance-
Patients with COPDCAT-Questionnaire-
Patients with AsthmaRespiratory Questionaire-
Patients with AsthmaMeasurement of respiratory mouth pressure-
Patients with AsthmaSNIP-
Patients with Asthma60 seconds sit-to-stand test-
Patients with AsthmaElectromyography-
Patients with AsthmaLung Function-
Patients with COPDLung Function-
Patients with FibrosisRespiratory Questionaire-
Patients with FibrosisSNIP-
Patients with AsthmaIntercostal Muscle Ultrasound-
Patients with AsthmaMRC Breathlessness Scale-
Patients with COPDBorg scale-
Patients with COPDMRC Breathlessness Scale-
Patients with COPDMeasurement of respiratory mouth pressure-
Patients with COPD60 seconds sit-to-stand test-
Patients with Pulmonary HypertensionIntercostal Muscle Ultrasound-
Patients with Pulmonary HypertensionSNIP-
Patients with Fibrosis6-minute walking distance-
Patients with COPDElectromyography-
Patients with FibrosisDiaphragm Ultrasound-
Patients with Pulmonary HypertensionRespiratory Questionaire-
Patients with Pulmonary Hypertension6-minute walking distance-
Patients with Pulmonary HypertensionElectromyography-
Patients with COPDRespiratory Questionaire-
Patients with COPDSNIP-
Patients with FibrosisMeasurement of respiratory mouth pressure-
Patients with Fibrosis60 seconds sit-to-stand test-
Patients with Pulmonary HypertensionLung Function-
Patients with Pulmonary HypertensionDiaphragm Ultrasound-
Patients with Pulmonary HypertensionMeasurement of respiratory mouth pressure-
Patients with Pulmonary HypertensionEuropean Society of Cardiology (ESC)/ European Respiratory Society (ERS) risk group-
Patients with Pulmonary Hypertension60 seconds sit-to-stand test-
Primary Outcome Measures
NameTimeMethod
Dyspnea Borg scale 1 to 10follow up 18 months after recruitment

Borg scale before and after "6 minute walking distance" test. Lower scores show fewer dyspnea, higher scores indicate more dyspnea.

Secondary Outcome Measures
NameTimeMethod
Blood Gas Analysis6 months recruiting

pH scale

Sit-to stand-test (60 seconds)6 months recruiting

Measurement of achieved repetitions of standing up and sitting down from an initial seated position in 60 seconds.

New York Heart Association (NYHA) classification scale 1 to 46 months recruiting, follow up up to 18 months after last recruitment

Patients are linked to a NYHA degree. Lower scores show fewer dyspnea, higher scores indicate more dyspnea.

Modified Medical Research Council (MRC) Breathlessness Scale 1 to 56 months recruiting, follow up up to 18 months after last recruitment

Patients are assessed and grouped according to their MRC Breathlessness Scale. Lower scores show fewer dyspnea, higher scores indicate more dyspnea.

COPD Assessment Test (CAT-Questionnaire) from 0 to 40 points.6 months recruiting, follow up up to 18 months after last recruitment

Patients are evaluated and placed into the corresponding groups. Lower scores show fewer dyspnea, higher scores indicate more dyspnea.

Diaphragm Thickening Ratio (DTR) in percent6 months recruiting

Via ultrasound, the diaphragm thickening ratio (DTR) was calculated as thickness at total lung capacity (TLC) divided by thickness at functional residual capacity (FRC).

Diaphragm ultrasound sniff velocity in cm/s6 months recruiting

Via ultrasound, the diaphragm sniff velocity was assessed during tidal breathing and following a maximum sniff.

Blood Gas Analysis in cmH2O6 months recruiting

carbon dioxide partial pressure (pCO2)

6 minute walking distance in m6 months recruiting

Measurement of achieved walking distance in 6 minutes

Chronic Respiratory Questionnaire (CRQ)6 months recruiting, follow up up to 18 months after last recruitment

Assessments of different domains (Emotional Domain, Dyspnea Domain, Mastery Domain, Fatigue Domain) in a standardized questionnaire on a scale from 1 to 7. The scores for each question of each dimension are added together and divided by the number of completed questions in each domain. In general, higher scores mean a worse outcome and lower scores mean a better outcome.

For the dyspnea domain for example, a high score means that patients have less dyspnea, and a low score means that patients have more dyspnea.

Body Plethysmography6 months recruiting

TLC (Total lung capacity) in percent predicted.

Diaphragm thickness at functional capacity (FRC)6 months recruiting

Via ultrasound, the diaphragm thickness at FRC is measured after a normal expiration.

Global Initiative for Asthma (GINA) classification6 months recruiting, follow up up to 18 months after last recruitment

Patients are assessed and grouped as mild, moderate, or severe according to the GINA classification.

Diaphragm thickness at Total lung capacity (TLC)6 months recruiting

Via ultrasound, the diaphragm thickness at TLC is measured at the maximum point of inspiration.

Intercostal Muscle ultrasound thickness at Total lung capacity (TLC) in cm6 months recruiting

Via ultrasound, the intercostal thickness at TLC is measured at the maximum point of inspiration.

Intercostal Muscle ultrasound thickness at functional capacity (FRC) in cm6 months recruiting

Via ultrasound, the intercostal thickness at FRC is measured after a normal expiration.

Intercostal Muscle Thickening Ratio in percent6 months recruiting

Via ultrasound, the intercostal muscle thickening ratio was calculated as thickness at total lung capacity (TLC) divided by thickness at functional residual capacity (FRC).

Maximum Inspiratory Pressure (MIP) in percent predicted6 months recruiting

Measurement of Maximum Inspiratory Pressure

Maximum Expiratory Pressure (MEP) in percent predicted6 months recruiting

Measurement of Maximum Expiratory Pressure

Sniff Nasal Inspiratory Pressure (SNIP) in percent predicted6 months recruiting

Measurement of Sniff Nasal Inspiratory Pressure

Blood Gas Analysis in mmol/l6 months recruiting

Base Excess

Electromyography (EMG)6 months recruiting

Measurement of electrical activity during different breathing maneuvers (Sniff, Cough, Valsalva, Mueller) via superficial electrodes placed on the diaphragm and accessory respiratory muscles (Sternocleidomastoideus muscle, intercostal muscles).

Blood Gas Analysis in (I1/s) percent6 months recruiting

Base Excess

Trial Locations

Locations (1)

RWTH Aachen University Hospital

🇩🇪

Aachen, North Rhine-westphalia, Germany

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