Impulse Oscillometry for Prognostication in Idiopathic Pulmonary Fibrosis

Study Overview
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Brief Summary
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A 5-point decline of forced vital capacity expressed as % predicted, over 6 months, is the current definition of disease progression (fast decline in lung function) in idiopathic pulmonary fibrosis. There is a need for techniques allowing to characterize disease progression earlier, so that treatment may be adapted as early as possible in the lack of a response. Hypothesis. Our hypothesis is that 3-month changes of lung function parameters measured by a novel technique, impulse oscillometry, predicts 6-month changes in forced vital capacity in idiopathic pulmonary fibrosis.

Detailed Description
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A 5-point decline of forced vital capacity expressed as % predicted, over 6 months, is the current definition of disease progression (fast decline in lung function) in idiopathic pulmonary fibrosis. There is a need for techniques allowing to characterize disease progression earlier, so that treatment may be adapted as early as possible in the lack of a response. Hypothesis. Our hypothesis is that 3-month changes of lung function parameters measured by a novel technique, impulse oscillometry, predicts 6-month changes in forced vital capacity in idiopathic pulmonary fibrosis.

Official Title
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Impulse Oscillometry for Prognostication in Idiopathic Pulmonary Fibrosis

Conditions
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Idiopathic Pulmonary Fibrosis

Intervention / Treatment
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* Diagnostic Test: Impulse Oscillometry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 45 years. Idiopathic Pulmonary Fibrosis defined Interstitial Lung Diseases with 1) lack of any known cause for Interstitial Lung Diseases and 2) either the definite usual interstitial pneumonia pattern at CT scan, or the usual interstitial pneumonia (definite, probable or possible) pattern at lung biopsy, according to the Lung Function Group of the French Pulmonology Society criteria. Exclusion Criteria: History of chronic obstructive airway disease. History of congestive heart failure. Emphysema-fibrosis syndrome, defined as emphysematous lesions involving >15% of the lung area at the level of the aortic arch (upper lobes). History of lower respiratory infection or acute respiratory failure of any cause less than 90 days before inclusion. Opposition to data processing.

Ages Eligible for Study
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Minimum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Impulse Oscillometry<br>Patients with Idiopathic Pulmonary Fibrosis. The objective is to determine whether another lung function technique, impulse oscillometry, is of interest to identify disease progression before changes in forced vital capacity can be ascertained. | Diagnostic Test: Impulse Oscillometry<br>* Impulse Oscillometry will be performed in addition to usual care<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Performance of the 5-Hz reactance of the respiratory system (Xsr5) variation at 3 months, for the diagnosis of rapid decline in lung function. | Receiver operating characteristics curves will be used to determine diagnostic performance. | Baseline, 3 months, 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Performance of the 3-month variation in additional impulse oscillometry parameters for the diagnosis of rapid decline in lung function | Receiver operating characteristics curves will be used to determine diagnostic performance. | Baseline, 3 months, 6 months | 
| Performance of baseline impulse oscillometry parameters for the diagnosis of rapid decline in lung function | Receiver operating characteristics curves will be used to determine diagnostic performance. | Baseline, 3 months, 6 months | 
| Assess correlations between impulse oscillometry parameters and forced vital capacity | Forced vital capacity is the total amount of air exhaled during the Forced expiratory volume test (how much air a person can exhale during a forced breath) | Baseline, 3 months, 6 months | 
| Assess correlations between impulse oscillometry parameters and exertional dyspnea | Dyspnea is assessed by the baseline dyspnea questionnaire and the transitional dyspnea questionnaire | Baseline, 3 months, 6 months | 
| Assess correlations between impulse oscillometry parameters and the extent of either fibrosis or emphysema lesions on CT scans | Lesions are scored by trained observers. | Baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Idiopathic Pulmonary Fibrosis, Impulse Oscillometry, Forced Vital Capacity