Measuring dyspnoea: new multidimensional instruments to match our 21st century understanding

[Effects of gender on pulmonary rehabilitation outcomes in patients with COPD]

INTRODUCTION

COPD has become more prevalent among women, revealing a specific feminine phenotype. Women experience greater dyspnea and a more impaired quality of life. The main objective of this study was to assess the effect of gender on dyspnea during a pulmonary rehabilitation program (PRP).

METHODS

Retrospective study including COPD patients having participated in PRPs. The following data were analyzed according to gender before and after a PRP: dyspnea, quality of life, anxiety and depression, exercise capacity, muscle function (quadriceps and inspiratory muscles).

RESULTS

More than 500 patients (252 men and 252 women) were included. We did not find a significant effect of gender on the evolution of dyspnea, anxiety or depressive disorders, exercise capacity, inspiratory muscle strength, or overall quality of life score. That said, we found a possible effect on the sub-scores of the quality of life questionnaire, and regarding quadriceps strength. All criteria improved during the program in both groups.

CONCLUSIONS

During a PRP, gender does not impact the evolution of dyspnea. While women may nonetheless benefit to a greater extent in terms of quality of life sub-scores (impact, activities, symptoms) and quadriceps strength, these results still require confirmation.

Efficacy and cerebral mechanisms of acupuncture for chronic obstructive pulmonary disease: study protocol for a multicenter, randomized controlled neuroimaging trial

Introduction

Although acupuncture is recommended by chronic obstructive pulmonary disease (COPD) treatment guidelines owing to its effects on dyspnea, the underlying neurobiological mechanisms of these effects remain unclear. This study aims to evaluate the efficacy of acupuncture in patients with stable COPD and explore the possible involvement of specific brain regions.

Methods

This is a prospective, multicenter, single-blind, randomized controlled trial. A total of 90 participants will be recruited from three centers and will be randomly assigned in a 1:1 ratio to undergo acupuncture at acupoints on the disease-affected meridian (DAM) or non-acupoints on the non-affected meridian (NAM), in addition to routine pharmacological treatments. All participants will undergo 30 min of acupuncture three times a week for 8 weeks and will be followed up for 12 months. The primary outcome will be the severity of dyspnea, as measured using the Borg Dyspnea Scale and a visual analog scale at rest and after exercise. The secondary outcomes will include the multidimensional profile of dyspnea using Dyspnea-12, the modified Medical Research Council Dyspnea Scale, and the COPD assessment test; quality of life assessments using St George's Respiratory Questionnaire and the Hospital Anxiety and Depression Scale; and additional measurements of exacerbation frequency, pulmonary function, and the 6-min walking distance. Magnetic resonance imaging (MRI) will be performed before and after exercise to explore the potential neurobiological mechanisms of exertional dyspnea. Anxiety and depression will be measured and analyzed for their correlation with the activation of specific brain areas involved in dyspnea.

Discussion

This randomized controlled trial aims to use a multidimensional evaluation of the efficacy of acupuncture in relieving dyspnea in patients with COPD in terms of emotion and quality of life and explore the neurobiological mechanisms underlying the effects of acupuncture on dyspnea from an imaging perspective. It is expected to provide strong evidence to support the use of acupuncture in relieving dyspnea in patients with COPD and those with aother diseases involving dyspnea. Additionally, it provides novel insights into the central mechanisms of acupuncture intervention and dyspnea.

Trial registration

Chinese Clinical Trial Registry (https://www.chictr.org.cn/): ChiCTR2300071725.

[The role of the physiotherapist in the assessment and management of dyspnea]

The role of the physiotherapist in the assessment and management of dyspnea. Dyspnea is the most common symptom in cardio-respiratory diseases. Recently improved comprehension of dyspnea mechanisms have underlined the need for three-faceted assessment. The three key aspects correspond to the "breathing, thinking, functioning" clinical model, which proposes a multidimensional - respiratory, emotional and functional - approach. Before initiating treatment, it is essential for several reasons to assess each specific case, determining the type of dyspnea affecting the patient, appraising the impact of shortness of breath, and estimating the effectiveness of the treatment applied. The physiotherapist has a major role to assume in the care of dyspneic patients, not only in assessment followed by treatment but also as a major collaborator in a multidisciplinary team, especially with regard to pulmonary rehabilitation. The aim of this review is to inventory the existing assessment tools and the possible physiotherapies for dyspnea, using a holistic approach designed to facilitate the choice of techniques and to improve quality of care by fully addressing the patient's needs.

Qualitative validation of the modified Medical Research Council (mMRC) dyspnoea scale as a patient-reported measure of breathlessness severity

INTRODUCTION

The modified Medical Research Council (mMRC) dyspnoea scale is a measure of breathlessness severity recommended by guidelines and utilised as an inclusion criterion or endpoint for clinical trials. No studies have been conducted to validate the categorical descriptors against the dyspnoea severity grade.

METHODS

This study utilised cognitive interviews (Think Aloud method) to assess the content validity of the mMRC scale among 16 participants (13 with cardiac/respiratory disease). Participants were recruited to achieve representation across a variety of demographic factors. Interviews were conducted remotely via video conferencing and participants were presented with all 5 mMRC descriptors on screen in random order then asked to rank the statements "in order from the best breathing to the worst breathing".

RESULTS

Mean age of participants was 57 years (range 22-84 years). Eleven had multimorbidity (≥2 comorbidities) including COPD, asthma, lung cancer, lung infection, interstitial lung disease, heart failure, depression, and anxiety. Length of time with breathlessness ranged between 2 weeks and >25 years. The median rank of the mMRC grade descriptors was concordant for mMRC grades 0, 1 and 4 but not grades 2 and 3. Even so, substantial heterogeneity was found in the distribution of responses for mMRC grade 0.

CONCLUSION

Our study found substantial heterogeneity in participant grading of the mMRC descriptors, particularly for grades 0, 2 and 3, indicating that mMRC might not be a good discriminator of difference or change in dyspnoea severity. This study demonstrates the importance of content validation even for long-established PROs like mMRC.

Reliability, Validity, and Responsiveness of the DEG, a Three-Item Dyspnea Measure

BACKGROUND

Dyspnea is a common and debilitating symptom that affects many different patient populations. Dyspnea measures should assess multiple domains.

OBJECTIVE

To evaluate the reliability, validity, and responsiveness of an ultra-brief, multi-dimensional dyspnea measure.

DESIGN

We adapted the DEG from the PEG, a valid 3-item pain measure, to assess average dyspnea intensity (D), interference with enjoyment of life (E), and dyspnea burden with general activity (G).

PARTICIPANTS

We used data from a multi-site randomized clinical trial among outpatients with heart failure.

MAIN MEASURES

We evaluated reliability (Cronbach's alpha), concurrent validity with the Memorial-Symptom-Assessment-Scale (MSAS) shortness-of-breath distress-orbothersome item and 7-item Generalized-Anxiety-Disorder (GAD-7) scale, knowngroups validity with New-York-Heart-Association-Functional-Classification (NYHA) 1-2 or 3-4 and presence or absence of comorbid chronic obstructive pulmonary disease (COPD), responsiveness with the MSAS item as an anchor, and calculated a minimal clinically important difference (MCID) using distribution methods.

KEY RESULTS

Among 312 participants, the DEG was reliable (Cronbach's alpha 0.92). The mean (standard deviation) DEG score was 5.26 (2.36) (range 0-10) points. DEG scores correlated strongly with the MSAS shortness of breath distress-or-bothersome item (r=0.66) and moderately with GAD-7 categories (ρ=0.36). DEG scores were statistically significantly lower among patients with NYHA 1-2 compared to 3-4 [mean difference (standard error): 1.22 (0.27) points, p<0.01], and those without compared to with comorbid COPD [0.87 (0.27) points, p<0.01]. The DEG was highly sensitive to change, with MCID of 0.59-1.34 points, or 11-25% change.

CONCLUSIONS

The novel, ultra-brief DEG measure is reliable, valid, and highly responsive. Future studies should evaluate the DEG's sensitivity to interventions, use anchor-based methods to triangulate MCID estimates, and determine its prognostic usefulness among patients with chronic cardiopulmonary and other diseases.

'The body says it': the difficulty of measuring and communicating sensations of breathlessness

Breathlessness is a sensation affecting those living with chronic respiratory disease, obesity, heart disease and anxiety disorders. The Multidimensional Dyspnoea Profile is a respiratory questionnaire which attempts to measure the incommunicable different sensory qualities (and emotional responses) of breathlessness. Drawing on sensorial anthropology we take as our object of study the process of turning sensations into symptoms. We consider how shared cultural templates of 'what counts as a symptom' evolve, mediate and feed into the process of bodily sensations becoming a symptom. Our contribution to the field of sensorial anthropology, as an interdisciplinary collaboration between history, anthropology and the medical humanities, is to provide a critique of how biomedicine and cultures of clinical research have measured the multidimensional sensorial aspects of breathlessness. Using cognitive interviews of respiratory questionnaires with participants from the Breathe Easy groups in the UK, we give examples of how the wording used to describe sensations is often at odds with the language those living with breathlessness understand or use. They struggle to comprehend and map their bodily experience of sensations associated with breathlessness to the words on the respiratory questionnaire. We reflect on the alignment between cognitive interviewing as a method and anthropology as a disciplinary approach. We argue biomedicine brings with it a set of cultural assumptions about what it means to measure (and know) the sensorial breathless body in the context of the respiratory clinic (clinical research). We suggest the mismatch between the descriptions (and confusion) of those responding to the respiratory questionnaire items and those selecting the vocabularies in designing it may be symptomatic of a type of historical testimonial epistemic injustice, founded on the prioritisation of clinical expertise over expertise by experience.

Dificultad respiratoria y COVID-19: Un llamado a la investigación

La dificultad respiratoria, también conocida como disnea, es un síntoma frecuente que causa debilidad. Varios reportes han destacado la ausencia de disnea en un subgrupo de pacientes que padecen COVID-19, en la llamada hipoxemia «silenciosa» o «feliz». Los reportes también han mencionado la falta de una relación clara entre la gravedad clínica de la enfermedad y los niveles de disnea referidos por los pacientes. Se ha demostrado en gran medida que entre las complicaciones cerebrales del COVID-19 hay alta prevalencia de encefalopatía aguda, que podría afectar el procesamiento de las señales aferentes o bien la modulación descendente de las señales de disnea. En esta revisión pretendemos destacar los mecanismos implicados en la disnea y resumir la fisiopatología del COVID-19 y sus efectos en la interacción cerebro-pulmón. Posteriormente, presentamos hipótesis sobre la alteración de la percepción de la disnea en pacientes con COVID-19 y sugerimos formas de investigar más a fondo este fenómeno.

Atemnot und COVID-19: Ein Aufruf zu mehr Forschung

Atemnot, auch als Dyspnoe bezeichnet, ist ein häufiges und lähmendes Symptom. In mehreren Berichten wurde die Abwesenheit von Atemnot bei einer Untergruppe von Patienten mit COVID-19 hervorgehoben, die manchmal als «stille» oder «glückliche Hypoxie» bezeichnet wird. Ebenfalls wurde in Berichten erwähnt, dass es an einem klaren Zusammenhang zwischen dem klinischen Schweregrad der Erkrankung und der von den Patienten berichteten Schwere der Atemnot fehlt. Die zerebralen Komplikationen von COVID-19 sind weitgehend nachgewiesen, mit einer hohen Prävalenz akuter Enzephalopathien, die möglicherweise die Verarbeitung afferenter Signale oder die absteigende Modulation von Atemnotsignalen beeinträchtigen könnte. In dieser Übersichtsarbeit möchten wir die an der Atemnot beteiligten Mechanismen hervorheben und die Pathophysiologie von COVID-19 und den bekannten Auswirkungen der Erkrankung auf die Interaktion von Gehirn und Lunge zusammenfassen. Anschließend stellen wir Hypothesen für die Veränderung der Wahrnehmung von Atemnot bei COVID-19-Patienten auf und schlagen Möglichkeiten vor, mit denen dieses Phänomen weiter erforscht werden könnte.

Feasibility of completing Multidimensional Dyspnea Profile and Dyspnea-12 over the telephone in patients with oxygen-dependent disease

Background

Breathlessness is prevalent in severe disease and consists of different dimensions that can be measured using the Multidimensional Dyspnea Profile (MDP) and Dyspnea-12 (D-12). We aimed to evaluate the feasibility of MDP and D-12 over telephone interviews in oxygen-dependent patients, compared with other patient-reported outcomes (modified Medical Research Council (mMRC) and Chronic Obstructive Pulmonary Disease Assessment Test (CAT)) and with completion by hand.

Methods

Cross-sectional, telephone study of 50 patients with home oxygen therapy. Feasibility was assessed as completion time (self-reported by patients and measured), difficulty (self-reported) and help required to complete the instruments (staff). Completion time was compared with mMRC and CAT, and feasibility was compared with completion by hand in cardiopulmonary outpatients (n=182). Feasibility by age and gender was analysed using logistic regression.

Results

Of 136 patients approached, 50 (37%) participated (mean age: 72±10 years, 66% women). Completion times (in minutes) were relatively short for MDP (self-reported 6 (IQR 5–10), measured 8 (IQR 6–10)) and D-12 (self-reported 5 (IQR 3–8), measured 3 (IQR 3–4)), and slightly longer than mMRC (median 1 (IQR 1–1)) and CAT (median 3 (IQR 2–5)). Even though the majority of patients required no help, more assistance was required by older patients. Compared with patients reporting by hand, completion over the telephone required somewhat longer time and more assistance.

Conclusion

Many patients with severe oxygen-dependent disease were unable or unwilling to assess symptoms over the telephone. However, among those able to participate, MDP and D-12 are feasible to measure multiple dimensions of breathlessness over the telephone.

Breathlessness and COVID-19: A Call for Research

Breathlessness, also known as dyspnoea, is a debilitating and frequent symptom. Several reports have highlighted the lack of dyspnoea in a subgroup of patients suffering from COVID-19, sometimes referred to as “silent” or “happy hyp­oxaemia.” Reports have also mentioned the absence of a clear relationship between the clinical severity of the disease and levels of breathlessness reported by patients. The cerebral complications of COVID-19 have been largely demonstrated with a high prevalence of an acute encephalopathy that could possibly affect the processing of afferent signals or top-down modulation of breathlessness signals. In this review, we aim to highlight the mechanisms involved in breathlessness and summarize the pathophysiology of COVID-19 and its known effects on the brain-lung interaction. We then offer hypotheses for the alteration of breathlessness perception in COVID-19 patients and suggest ways of further researching this phenomenon.

Validity and reliability of the Multidimensional Dyspnoea Profile in older adults

Breathlessness is a common and distressing symptom in older adults and an independent predictor of adverse outcomes and yet its multidimensional assessment has not been validated in older adults. We apply and validate the Multidimensional Dyspnoea Profile (MDP) in a sample of adults 75 years and older in Belgium.

Breathlessness was rated with the MDP, the modified Borg Dyspnoea Scale (mBDS), the Short Physical Performance Battery (SPPB, a numerical rating scale for intensity and unpleasantness both before and after exertion), as well as with the Medical Research Council (MRC) Dyspnoea Scale. The Hospital Anxiety and Depression Scale (HADS) assessed the affective status. Factor structure was analysed with exploratory principal components analysis, internal consistency with Cronbach's alpha and concurrent validity with Spearman's correlation coefficients with other breathlessness scales, HADS and SPPB scores.

In 96 participants (mean age 85 years; 34% men) who rated breathlessness at both assessment points, exploratory principal components analysis identified two components: Immediate Perception (IP) and Emotional Reaction (ER), explaining most of the MDP item variance (65.37% before and 71.32% after exertion). Internal consistency was moderate to high for MDP-IP (Cronbach's alpha = 0.86 before and 0.89 after exertion) and MDP-ER (Cronbach's alpha = 0.89 before and 0.91 after exertion). The correlation patterns of MDP-IP and MDP-ER with other tests confirmed concurrent validity.

The domain structure, reliability and concurrent validity of MDP for breathlessness before and after exertion were confirmed in a sample of adults 75 years and older, supporting its use and further research for the multidimensional profiling of breathlessness in older adults.

Domain structure, reliability and concurrent validity of the MDP were confirmed in a sample of adults aged ≥75 years before and after exertion, supporting its use for the multidimensional assessment of breathlessness in this age grouphttps://bit.ly/3emiNRW

Dyspnea in COPD: New Mechanistic Insights and Management Implications

Dyspnea is the most common symptom experienced by patients with chronic obstructive pulmonary disease (COPD). To avoid exertional dyspnea, many patients adopt a sedentary lifestyle which predictably leads to extensive skeletal muscle deconditioning, social isolation, and its negative psychological sequalae. This "dyspnea spiral" is well documented and it is no surprise that alleviation of this distressing symptom has become a key objective highlighted across COPD guidelines. In reality, this important goal is often difficult to achieve, and successful symptom management awaits a clearer understanding of the underlying mechanisms of dyspnea and how these can be therapeutically manipulated for the patients' benefit. Current theoretical constructs of the origins of activity-related dyspnea generally endorse the classical demand-capacity imbalance theory. Thus, it is believed that disruption of the normally harmonious relationship between inspiratory neural drive (IND) to breathe and the simultaneous dynamic response of the respiratory system fundamentally shapes the expression of respiratory discomfort in COPD. Sadly, the symptom of dyspnea cannot be eliminated in patients with advanced COPD with relatively fixed pathophysiological impairment. However, there is evidence that effective symptom palliation is possible for many. Interventions that reduce IND, without compromising alveolar ventilation (VA), or that improve respiratory mechanics and muscle function, or that address the affective dimension, achieve measurable benefits. A common final pathway of dyspnea relief and improved exercise tolerance across the range of therapeutic interventions (bronchodilators, exercise training, ambulatory oxygen, inspiratory muscle training, and opiate medications) is reduced neuromechanical dissociation of the respiratory system. These interventions, singly and in combination, partially restore more harmonious matching of excessive IND to ventilatory output achieved. In this review we propose, on the basis of a thorough review of the recent literature, that effective dyspnea amelioration requires combined interventions and a structured multidisciplinary approach, carefully tailored to meet the specific needs of the individual.

A Multidimensional Profile of Dyspnea in Hospitalized Patients

BACKGROUND

Dyspnea is prevalent among hospitalized patients but little is known about the experience of dyspnea among inpatients. We sought to characterize the multiple sensations and associated emotions of dyspnea in patients admitted with dyspnea to a tertiary care hospital.

METHODS

We selected patients who reported breathing discomfort of at least 4/10 on admission (10 = unbearable). Research staff recruited 156 patients within 24 hours of admission and evaluated daily patients' current and worst dyspnea with the Multidimensional Dyspnea Profile; patients participated in the study 2.6 days on average. The Multidimensional Dyspnea Profile assesses overall breathing discomfort (A₁), intensity of five sensory qualities of dyspnea, and 5 negative emotional responses to dyspnea. Patients were also asked to rate whether current levels of dyspnea were "acceptable."

RESULTS

At the time of the first research interview, patients reported slight to moderate dyspnea (A₁ median 4); however, most patients reported experiencing severe dyspnea in the 24 hours before the interview (A₁ mean 7.8). A total of 54% of patients with dyspnea ≥4 on day 1 found the symptom unacceptable. The worst dyspnea each day in the prior 24 hours usually occurred at rest. Dyspnea declined but persisted through hospitalization for most patients. "Air hunger" was the dominant sensation, especially when dyspnea was strong (>4). Anxiety and frustration were the dominant emotions associated with dyspnea.

CONCLUSIONS

This first multidimensional portrait of dyspnea in a general inpatient population characterizes the sensations and emotions dyspneic patients endure. The finding that air hunger is the dominant sensation of severe dyspnea has implications for design of laboratory models of these sensations and may have implications for targets of palliation of symptoms.

Prevalence of Dyspnea Among Hospitalized Patients at the Time of Admission

CONTEXT

Dyspnea is an uncomfortable and distressing sensation experienced by hospitalized patients.

OBJECTIVES

There is no large-scale study of the prevalence and intensity of patient-reported dyspnea at the time of admission to the hospital.

METHODS

Between March 2014 and September 2016, we conducted a prospective cohort study among all consecutive hospitalized patients at a single tertiary care center in Boston, MA. During the first 12 hours of admission to medical-surgical and obstetric units, nurses at our institution routinely collect a patient's 1) current level of dyspnea on a 0-10 scale with 10 anchored at "unbearable," 2) worst dyspnea in the past 24 hours before arrival at the hospital on the same 0-10 scale, and 3) activities that were associated with dyspnea before admission. The prevalence of dyspnea was identified, and tests of difference were performed across patient characteristics.

RESULTS

We analyzed 67,362 patients, 12% of whom were obstetric patients. Fifty percent of patients were admitted to a medical-surgical unit after treatment in the emergency department. Among all noncritically ill inpatients, 16% of patients experienced dyspnea in the 24 hours before the admission. Twenty-three percent of patients admitted through the emergency department reported any dyspnea in the past 24 hours. Eleven percent experienced some current dyspnea when interviewed within 12 hours of admission with 4% of patients experiencing dyspnea that was rated 4 or greater. Dyspnea of 4 or more was present in 43% of patients admitted with respiratory diagnoses and 25% of patients with cardiovascular diagnoses. After multivariable adjustment for severity of illness and patient comorbidities, patients admitted on the weekend or during the overnight nursing shift were more likely to report dyspnea on admission.

CONCLUSION

Dyspnea is a common symptom among all hospitalized patients. Routine documentation of dyspnea is feasible in a large tertiary care center.

Translation and Validation of the Multidimensional Dyspnea-12 Questionnaire

INTRODUCTION

Dyspnea is a multidimensional symptom, but this multidimensionality is not considered in most dyspnea questionnaires. The Dyspnea-12 takes a multidimensional approach to the assessment of dyspnea, specifically the sensory and the affective response. The objective of this study was to translate into Spanish and validate the Dyspnea-12 questionnaire.

METHODS

The original English version of the Dyspnea-12 questionnaire was translated into Spanish and backtranslated to analyze its equivalence. Comprehension of the text was verified by analyzing the responses of 10 patients. Reliability and validation of the questionnaire were studied in an independent group of COPD patients attending the pulmonology clinics of Hospital Universitario Marqués de Valdecilla, diagnosed and categorized according to GOLD guidelines.

RESULTS

The mean age of the group (n=51) was 65 years and mean FEV1 was 50%. All patients understood all questions of the translated version of Dyspnea-12. Internal consistency of the questionnaire was α=0.937 and intraclass correlation coefficient was=.969; P<.001. Statistically significant correlations were found with HADS (anxiety r=.608 and depression r=.615), mMRC dyspnea (r=.592), 6MWT (r=-0.445), FEV1 (r=-0.312), all dimensions of CRQ-SAS (dyspnea r=-0.626; fatigue r=-0.718; emotional function r=-0.663; mastery r=-0.740), CAT (r=0.669), and baseline dyspnea index (r=-0.615). Dyspnea-12 scores were 10.32 points higher in symptomatic GOLD groups (B and D) (P<.001).

CONCLUSION

The Spanish version of Dyspnea-12 is a valid and reliable instrument to study the multidimensional nature of dyspnea.