Breathlessness despite optimal pathophysiological treatment: on the relevance of being chronic

To the Editor:

In the May 2017 issue of the European Respiratory Journal (ERJ), Johnson et al. [1] proposed the term “chronic breathlessness syndrome” to describe the clinical situation in which “breathlessness that persists despite optimal treatment of the underlying pathophysiology and results in disability for the patient”. The term “disability” in this definition corresponds to “physical limitations and/or a variety of adverse psychosocial, spiritual or other consequences”, which very closely matches the World Health Organization definition of the word [2]. The relationship between breathlessness and disability was well captured in the foreword of a document published in 2013 by the Forum of International Respiratory Societies [3], which begins: “When we are healthy, we take our breathing for granted […]. But when our lung health is impaired, nothing else but our breathing really matters”. This has become the “catch phrase” of the French lung health foundation (“Fondation du Souffle”, www.lesouffle.org). The explicit definition of “chronic breathlessness” as proposed by Johnson et al. [1] differs very little from the implicit definition of “refractory breathlessness”, the term previously used in many studies, and which was proposed as a distinct entity by some of the authors of a previously published ERJ article [4]. Johnson et al. [1] submit that defining and naming this new syndrome will improve the visibility of a distressing and debilitating condition that is too often overlooked and neglected [5]. They postulate that this enhanced visibility will result in improved care and organisation of care, stronger research [6], and greater empowerment for patients and their caregivers. The Editorial by Başoğlu [7] published in the May 2017 issue of the ERJ throws new light on this notion of empowerment. Making a daring but fascinating parallel between untreated dyspnoea and torture, Başoğlu [7] reminds us how and why addressing dyspnoea in general (and probably “chronic breathlessness” in particular) is a fundamental issue not only from the point of view of medicine per se, but also from the point of view of human rights (on this, see also [8]). He also makes a very convincing case for the importance of empowerment in the management of dyspnoea. Still in the same issue of the ERJ, Calverley [9] comments on the new syndrome and, like us, concurs with Johnson et al. [1] about the relevance of making breathlessness a foremost concern of every clinician.

In order to contribute to the discussion called for in the article by Johnson et al. [1], we (a French speaking group of physicians with a special interest in dyspnoea) would like to make a few comments about this article and the accompanying Editorial by Calverley [9]. These comments mostly pertain to the choice of words that has been made to name the new syndrome. In no way should they be interpreted as an expression of disagreement with the proposed approach and its aims; some of the authors of the present letter (C. Morélot-Panzini, D. Adler, E. Allard, C. Chenivesse, P. Laveneziana, L. Laviolette, C. Peiffer and T. Similowski) participated in the “Dyspnea 2016” symposium during which the “chronic breathlessness” discussion was finalised; one of the authors of the article by Johnson et al. [1] is also a co-author of this letter (T. Similowski). Our letter should be taken as a mere illustration of the fact that differences of opinions always exist within consensus, and also as a substantiation of the dynamic nature of the syndrome-naming process that is put forward by Johnson et al. [1].

Our first comment concerns using “breathlessness” rather than “dyspnoea” in the name of the syndrome. As “dyspnoea” is widely used in the medical literature and in medical practice, it would be useful to clarify whether “chronic breathlessness syndrome” and “chronic dyspnoea syndrome” can be used interchangeably, and if not, to explain why. This is an important issue, particularly for non-native English speakers. The answer to this question can have a significant impact on translations of the name of the new syndrome in other languages.

Our second comment pertains to the use of the term “optimal treatment” in the definition of the syndrome, which can be ambiguous. We understand that, in this context, “optimal” means “maximal”, or “state-of-the art”, but this may not be exactly the same thing: in some conditions characterised by a marked irreversible component, such as chronic obstructive pulmonary disease (COPD) or pulmonary fibrosis, maximal therapy can fail to provide optimal results both physiologically and, obviously, symptomatically. Beyond semantics, we feel that it is extremely important not to label a patient as suffering from “chronic breathlessness” before being sure that everything has been done to correct the underlying pathophysiological condition, as failure to do so would be associated with a risk of depriving the patient of effective interventions at that time or in the future. For example, if “optimal” treatment of an underlying condition exists but is not available for a given patient at a given time, or if the patient refuses this treatment for any reason, the use of nonspecific symptomatic treatment to alleviate dyspnoea would be valid and in fact essential (as the Editorial by Başoğlu [7] clearly reminds us). And yet, the definition of “chronic breathlessness” would not be met, and placing such patients under the “chronic breathlessness” umbrella would carry the risk of forgetting that optimal treatment has not been applied and should be undertaken as soon as it becomes possible.

Our third comment pertains to the choice of the term “syndrome” itself. In his Editorial, Calverley [9] challenges this choice and seems to suggest that “syndrome” should only be used to identify “consistent groups of patients” with a “likely primary condition”. Another reason to challenge the term “syndrome” is related to its very definition as “a group of signs and symptoms that occur together and characterise a particular abnormality or condition” (https://www.merriam-webster.com/dictionary/syndrome). This definition is directly derived from the Greek etymology of the word, which means “running together” and thereby implies a combination of items. Since “chronic breathlessness syndrome” apparently comprises only one symptom (dyspnoea), use of the term “syndrome” may be deemed inappropriate. However, the clinical situations covered by “chronic breathlessness syndrome” actually share much more than dyspnoea, as they also have the multiple deleterious consequences of this symptom (e.g. psychological, social, etc.) in common. The term “syndrome” may therefore be very appropriate, particularly to attribute a consistency to otherwise inconsistent groups of patients. This seems to be exactly what has been achieved with “chronic pain syndrome”. “Chronic breathlessness syndrome” has the advantage of defining a common basis for the care of patients with a variety of diseases and disorders who are, however, “unified” (as should their caregivers be) by breathlessness, or, more generally, “respiratory suffering”. It suggests that all respiratory physicians (and beyond that, all physicians caring for patients with dyspnogenic diseases, and there are many of them) should be familiar with the principles of dyspnoea management in addition to the management of the underlying disease (of note, this is explicitly stated in the 2017 edition of the GOLD statement, which indicates that “all clinicians managing patients with COPD should be aware of the effectiveness of palliative approaches to symptom control and use these in their practice” (see table 4.9 in [10])). Using “symptom” instead of “syndrome” (or omitting “syndrome”), as suggested by Calverley [9], would carry the risk of neglecting the multidimensional and pervasive nature of dyspnoea [11–15]. The process initiated by Johnson et al. [1] is designed to convince caregivers, and others, that the care of dyspnoea cannot be limited to the treatment of the symptom, but should address its behavioural and socio-psychological consequences. Consequently, we believe that “syndrome” is an appropriate term, as it gives a holistic dimension to the management of dyspnoea.

Our fourth comment, and in fact the most important comment, concerns the term “chronic” in the name of the new syndrome. This choice emerged from a Delphi process, which gives it validity. If one of the goals of creating the new syndrome is to give consistency and visibility to inconsistent and invisible groups of patients (see above), we believe that the word “chronic” could well be counterproductive in a number of cases, as it would deprive many patients of significant conceptual progress. Indeed, all of the concepts used to define “chronic breathlessness” in the article by Johnson et al. [1] can apply, word for word, to many clinical situations involving acute rather than chronic dyspnoea. For example, all patients hospitalised with severe acute exacerbations of COPD remain dyspnoeic at rest despite oxygen, bronchodilators and corticosteroids, with the corresponding lack of control emphasised by Başoğlu [7] and with shrunken lives. This description exactly fits the definition of the syndrome proposed by Johnson et al. [1], with the exception of the time frame. Although this is not standard practice at the moment, these patients could, or more precisely should, be considered for dyspnoea-oriented treatment in addition to pathophysiology-oriented treatment. Even more striking in terms of the temporal dynamics of dyspnoea, is the fact that critically ill patients receiving mechanical ventilation often complain of breathlessness [16]. After dealing with the various technical aspects involved, including optimisation of inappropriate ventilator settings, many of these patients remain breathless [16], a situation strongly suspected to contribute to the development of post-traumatic stress syndrome [17]. It will be impossible to convince the intensivists in charge of such patients that they suffer from “chronic breathlessness”, even though relief of dyspnoea in this setting is a fundamental clinical mission [18, 19]. We believe that persistence of dyspnoea despite maximal pathophysiological treatment of an acute condition is not a fatality and is not more acceptable than it is in the context of a chronic condition. We therefore also believe that the principles governing the therapeutic approach to acute breathlessness should be exactly the same as the those governing the therapeutic approach to chronic breathlessness. Following are examples of clinical questions that can be formulated to support this contention: “Should noninvasive ventilation be considered in COPD patients during severe acute exacerbations despite complete normalisation of blood gases in response to conventional treatment, in order to alleviate dyspnoea?”; “Should we design trials of short-term, low-dose opioids in addition to pathophysiological treatment in severe exacerbations of COPD?”; “Should we re-think the management of opioids during mechanical ventilation with a dyspnoea paradigm in mind?”; “Should the concept of ‘integrated breathlessness service’, as developed in supportive care [20, 21], be transposed to the intensive care unit?”; “Is there any reason to think that empathy, education and cognitive therapies would not be effective if ‘breathlessness that persists despite treatment’ is acute rather than chronic”?; and so on. With this in mind, we are afraid that “chronic breathlessness syndrome” could be a misnomer because it would “miss” many “non-chronic” but nonetheless clinically relevant situations. Johnson et al. [1] and Calverley [9] briefly refer to this issue, but perhaps do not attribute sufficient importance to what could possibly be seen as a major gap by many practitioners. The name “persistent breathlessness” would have avoided this problem, because it would have covered all acute and chronic situations. “Persistent breathlessness” (or “resistant breathlessness”, or any other “time neutral” term) would also have had the advantage of clarifying the discourse in certain cases, possibly with some added teaching value. Let's take an example: “Dear colleague, I am referring this COPD patient to you. She has been treated with dual bronchodilation and inhaled corticosteroids since last year, and presents with chronic breathlessness.” It could take quite a long time for this statement to be readily understood by the majority of practitioners. In contrast, “Dear colleague, I am referring this COPD patient to you, who has been treated with dual bronchodilation and inhaled corticosteroids since last year because she complains of persistent breathlessness” can probably more readily understood and is more “teachable” (and “persistent” does not have the negative connotation of “refractory”, which for this reason has become “chronic” during the Delphi process elaborated by Johnson et al. [1]).

All physicians dealing with dyspnoeic patients must have the same objective, namely to alleviate dyspnoea by all means, combining “pathophysiological” and “syndrome-based” strategies, irrespective of the time-frame involved. We suggest that this general goal would be more effectively promoted by the term “persistent breathlessness syndrome” than by “chronic breathlessness syndrome” and we therefore advocate an evolution in this direction. Polling the ERJ readership could perhaps provide useful information on this subject.

Disclosures