Hyperventilation Syndrome clinical trials

Dysfunctional Breathing: Characterisation and Assessment

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).