Dysfunctional Breathing: Characterisation and Assessment

Summary

Dysfunctional breathing (DB) is a respiratory condition characterised by an abnormal breathing pattern, among other complaints, that can occur either in the absence of other pathophysiology (primary DB), e.g. anxiety-related factors, or secondary to cardiopulmonary disease (secondary DB), e.g. asthma. As a consequence, patients may experience breathlessness and present with periods of increased ventilation or erratic breathing, interspersed with episodes of breath holding or deep sighs. In addition to respiratory symptoms, DB also generates non- respiratory symptoms (e.g. dizziness and increased heart rate). It is estimated 1 in 10 people in the United Kingdom (UK) have DB. However, DB remains poorly understood, with no standardised approach to diagnosis and assessment.

The purposes of this study are:

Study 1) To identify physiological, functional and psychological characteristics of participants with DB compared to healthy participants.

Firstly, symptoms, lung function, respiratory gas analysis, exercise capacity, respiratory muscle function, respiratory motion, level of physical activity, quality of life and anxiety \& depression scores will be assessed in 20 participants with primary DB, 20 with secondary DB and compared to 20 healthy participants.

Study 2) To develop an assessment tool based on physiological, functional or psychological variables found to be different between any of the 3 groups in Study 1.

In order to do that, 54 people with DB (between primary and secondary) and 27 people presenting with breathlessness secondary to restrictive lung disease will be assessed. Analysis of these data will determine whether these variables can be used as a diagnostic tool capable of distinguishing DB from restrictive lung diseases characterised by breathlessness.

The recruitment period will be 1-2 years, with an individual participation of 9 days; 1-day on site testing, plus 7-day home activity monitoring, and 1 day to return the activity monitor (which will happen whenever the participant needs to return to the site).

Conditions

• Respiration Disorder
• Hyperventilation Syndrome
• Breathlessness
• Breath Shortness

Interventions

OTHER

Short-form survey instrument

Questionnaire with questions about quality of life. Takes about 5 minutes to be completed.

OTHER

Demographic data

height, weight, age, gender, list of comorbidities, health history, level of physical activity, medicines in use. Takes about 10 minutes to be completed.

OTHER

Hospital Anxiety and Depression Scale

Questionnaire with questions about anxiety and depression. Takes about 5 minutes to be completed.

OTHER

Nijmegen questionnaire

Answering questions about symptoms related to breathing. Takes about 5 minutes to be completed.

OTHER

The Self-evaluation of breathing questionnaire

Answering questions about self-evaluation of breathing. Takes about 5 minutes to be completed

OTHER

six-minute exercise test

Cycling against certain load in a bicycle for 6 minutes. Takes about 16 minutes to be completed together with indirect calorimetry, oxygen saturation monitoring, heart rate variability analysis and continuous monitoring of arterial blood pressure).

OTHER

Indirect calorimetry

Breathing through a mask that measures levels of oxygen, carbon dioxide, breathing frequency and others (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.

OTHER

Oxygen saturation monitoring

The measurement of the amount of oxygen which is attached to haemoglobin molecules (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.

OTHER

Heart rate variability analysis

Measurement of the variation in the beat-to-beat interval (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.

OTHER

Continuous measurement of arterial blood pressure

Measurement of blood pressure based on the peripheral pulse using a finger cuff (non-invasively). Takes about 16 minutes to be completed, together with the 6-minute exercise test.

DIAGNOSTIC_TEST

Lung function test

Breathing through a mouth-piece in many different ways in order to measure the function of the lungs (non-invasively).

OTHER

Respiratory muscle function

Breathing through a mouth-piece in many different ways in order to measure the function of the respiratory muscles (non-invasively).

OTHER

Manual assessment of respiratory motion

Measure of the movements of the thorax while the participant is breathing (non-invasively).

OTHER

Breath-hold test

Holding the breath a few times for as long as possible.

OTHER

Physical Activity monitoring

Wearing a light-weight activity monitor to be wore on the hip for 7 consecutive days during, at least, 8 hours per day.

OTHER

Asthma Control Questionnaire

Only for asthmatics: answering questions about the control the participant has over this respiratory condition/symptoms.

Sponsors & Collaborators

• University of Sao Paulo

  collaborator OTHER

• Brunel University

  lead OTHER

Principal Investigators

• Panagiota Smyrni, Dr · Brunel University London

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2020-08-08

Primary Completion

2021-04-30

Completion

2021-05-30

Countries

• United Kingdom

Study Locations