Description

Breathlessness is a debilitating symptom that results in poorer quality of life, increased hospitalisations, and increased mortality. Breathlessness is a complex multi-dimensional sensation with established bio-psycho-social influences (Hayen et al., 2013) that are likely to interact, though the mechanisms or relative contributions of these interactions are unknown (Oxley \& Macnaughton, 2016). Breathlessness is a hallmark feature of respiratory disease and is the primary reason for seeking healthcare advice and treatments. Though currently breathlessness management follows a one-size fits all approach and does not pay consideration to the unique and individual experience of breathlessness.

The breathing thinking functioning (BTF) model of breathlessness is a theoretical framework that attempts to explain this complex and multifactorial symptom, however it lacks scientific premise. Highlighting that physiology, psychology and function will all play a role in determining breathlessness for the individual. An additional complication, that is seldom explored is disordered breathing patterns. This is potentially bi-directional where by severe breathlessness could contribute to disordered breathing and/or disordered breathing could lead to severe breathlessness. There is currently no objective marker of disordered breathing pattern however, use of optoelectronic plethysmography (OEP) has shown promise in quantifying this phenomenon (Smyth, 2021). OEP is a novel technique, utilising 3-dimensional motion capture, and can be measured during exercise, using a cardiopulmonary exercise testing, which allows for monitoring of breathlessness and breathing pattern during exercise, commonly reported as troublesome by patients. OEP has been used in Chronic Obstructive Pulmonary Disease to assess hyperinflation, though evidence within respiratory disease is at its infancy, and has not been explored alongside other factors to understand the contribution of multiple factors of breathlessness. Therefore, there is a current gap in the literature exploring the interaction(s) of factors contributing to breathlessness severity, including the objective analysis of breathing pattern. Further understanding the breathlessness in this way could lead to personalisation or treatments increasing their effectiveness, and improving health and quality of life. The project will quantitatively measure breathlessness perception, alongside objective cardiorespiratory measures and background health and well-being data as well as OEP breathing pattern data (such as compartment contribution and inter-compartment asynchrony). This will allow an understanding of how each of these factors may affect interventions and differences in breathlessness experience and presentation, and subsequently the acceptability of breathlessness.