Validation of the Swedish Multidimensional Dyspnea Profile (MDP) in outpatients with cardiorespiratory disease

Which breathlessness dimensions associate most strongly with fatigue?-The population-based VASCOL study of elderly men

BACKGROUND

Breathlessness and fatigue are common symptoms in older people. We aimed to evaluate how different breathlessness dimensions (overall intensity, unpleasantness, sensory descriptors, emotional responses) were associated with fatigue in elderly men.

METHODS

This was a cross-sectional analysis of the population-based VAScular disease and Chronic Obstructive Lung Disease (VASCOL) study of 73-year old men. Breathlessness dimensions were assessed using the Dyspnoea-12 (D-12), Multidimensional Dyspnoea Profile (MDP), and the modified Medical Research Council (mMRC) scale. Fatigue was assessed using the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) questionnaire. Clinically relevant fatigue was defined as FACIT-F≤ 30 units. Scores were compared standardized as z-scores and analysed using linear regression, adjusted for body mass index, smoking, depression, cancer, sleep apnoea, prior cardiac surgery, respiratory and cardiovascular disease.

RESULTS

Of 677 participants, 11.7% had clinically relevant fatigue. Higher breathlessness scores were associated with having worse fatigue; for D-12 total, -0.35 ([95% CI] -0.41 to -0.30) and for MDP A1, -0.24 (-0.30 to -0.18). Associations were similar across all the evaluated breathlessness dimensions even when adjusting for the potential confounders.

CONCLUSION

Breathlessness assessed using D-12 and MDP was associated with worse fatigue in elderly men, similarly across different breathlessness dimensions.

Automated Oxygen Administration Alleviates Dyspnea in Patients Admitted with Acute Exacerbation of COPD: A Randomized Controlled Trial

Objective

Devices for Automated Oxygen Administration (AOA) have been developed to optimize the therapeutic benefit of oxygen supplementation. We aimed to investigate the effect of AOA on multidimensional aspects of dyspnea and as-needed consumption of opioids and benzodiazepines, as opposed to conventional oxygen therapy, in hospitalized patients with Acute Exacerbation of COPD (AECOPD).

Method and Patients

A multicenter randomized controlled trial across five respiratory wards in the Capital Region of Denmark. Patients admitted with AECOPD (n=157) were allocated 1:1 to either AOA (O2matic Ltd), a closed loop device automatically delivering oxygen according to the patient's peripheral oxygen saturation (SpO₂), or conventional nurse-administered oxygen therapy. Oxygen flows and SpO₂ levels were measured by the O2matic device in both groups, while dyspnea, anxiety, depression, and COPD symptoms were accessed by Patient Reported Outcomes.

Results

Of the 157 randomized patients, 127 had complete data for the intervention. The AOA reduced patients' perception of overall unpleasantness significantly on the Multidimensional Dyspnea Profile (MDP) with a difference in medians of -3 (p=0.003) between the intervention group (n=64) and the control group (n=63). The AOA also provided a significant between group difference in all single items within the sensory domain of the MDP (all p-values≤0.05) as well as in the Visual Analogue Scale - Dyspnea (VAS-D) within the past three days (p=0.013). All between group differences exceeded the Minimal Clinical Important Difference of the MDP and VAS-D, respectively. AOA did not seem to have an impact on the emotional response domain of the MDP, the COPD Assessment Test, the Hospital Anxiety and Depression Scale, or use of as-needed opioids and/or benzodiazepines (all p-values>0.05).

Conclusion

AOA reduces both breathing discomfort and physical perception of dyspnea in patients admitted with AECOPD but did not seem to impact the emotional status or other COPD symptoms.

Associations in Perceived Health and Persistent Breathlessness: A Cross-Sectional Study

Background

Persistent breathlessness is debilitating and increases in prevalence with advanced age and at end of life. This study aimed to evaluate any relationship between self-reported global impressions of change (GIC) in perceived health and breathlessness in older men.

Design

Cross-sectional study of 73-year-old Swedish men in the VAScular and Chronic Obstructive Lung disease study. A postal survey included items on perceived changes in health and breathlessness (GIC scales) and breathlessness (assessed using the modified Medical Research Council [mMRC] breathlessness scale, Dyspnea-12 and Multidimensional Dyspnea Scale) since age 65.

Results

Of 801 respondents, breathlessness (mMRC ≥2) was reported by 17.9%, worsening breathlessness by 29.1%, and worsening perceived health by 51.3%. Worsening breathlessness was strongly correlated with worsening perceived health (Pearson's correlation coefficient of 0.68 [p < 0.001] and Kendall's τ of 0.56 [p < 0.001]) and associated with more limited function (47.2% vs. 29.7%; p < 0.0001) and increased rates of anxiety/depression.

Conclusion

The strong correlation between perceived changes in health and persistent breathlessness helps delineate a more comprehensive picture of the challenges faced by older adults living with this disabling symptom.

Validation of the Dyspnoea-12 and Multidimensional Dyspnea profile among older Swedish men in the population

Background

The Dyspnoea-12 (D12) and Multidimensional dyspnea profile (MDP) are commonly used instruments for assessing multiple dimensions of breathlessness but have not been validated in older people in the population. The aim of this study was to validate the D12 and MDP in 73-years old men in terms of the instruments’ underlying factor structures, internal consistency, and validity.

Methods

A postal survey was sent out to a population sample of 73-years old men (n = 1,193) in southern Sweden. The two-factor structures were evaluated with confirmatory factor analysis, internal consistency with Cronbach's alpha, and validity using Pearson´s correlations with validated scales of breathlessness, anxiety, depression, fatigue, physical/mental quality of life, body mass index (BMI), and cardiorespiratory disease.

Results

A total 684 men were included. Respiratory and cardiovascular disease were reported by 17% and 38%, respectively. For D12 and MDP, the proposed two-factor structure was not fully confirmed in this population. Internal consistency was excellent for all D12 and MDP domain scores (Cronbach's alpha scores > 0.92), and the instruments’ domains showed concurrent validity with other breathlessness scales, and discriminant validity with anxiety, depression, physical/mental quality of life, BMI, and cardiorespiratory disease.

Conclusions

In a population sample of 73-years old men, the D12 and MDP had good psychometrical properties in terms of reliability and validity, which supports that the instruments are valid for use in population studies of older men.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03166-5.

Patients' lived experiences of breathlessness prior to prehospital care - A phenomenological study

Aims and objectives

The study aimed to describe how breathlessness is experienced by patients prior to prehospital care.

Design

A qualitative phenomenological design.

Methods

Lifeworld interviews were conducted with 14 participants. The analysis was carried out within the descriptive phenomenological framework.

Results

The essential meaning of the breathlessness phenomenon is described as an existential fear in terms of losing control over one’s body and dying, which involves a battle to try to regain control. This is further described by four constituents: being in an unknown body, striving to handle the situation, the ambiguity of having loved ones close and reaching the utmost border.

Conclusions

Patients describe a battling for survival. It is at the extreme limit of endurance that patients finally choose to call the emergency number. It is a challenge for the ambulance clinician (AC) to support these patients in the most optimal fashion.

Persisting breathlessness and activities reduced or ceased: a population study in older men

Introduction

Breathlessness is debilitating and increases in prevalence with age, with people progressively reducing their everyday activities to ‘self-manage’ it. This study aimed to evaluate the impact of breathlessness on function in terms of activities that have been reduced or ceased (‘compromised’) in older men.

Methods

A cross-sectional postal survey of Swedish 73-year-old man in the VAScular and Chronic Obstructive Lung disease study self-reporting on demographics, breathlessness (modified Medical Research Council (mMRC) scale, Dyspnoea-12, Multidimensional Dyspnea Scale) and its duration, anxiety/depression (Hospital Anxiety and Depression Scale), performance status (WHO Performance Status), everyday activities reduced/ceased and exertion.

Results

148/828 (17.9%) respondents reported breathlessness (mMRC >2), of whom 51.9% had reduced/ceased activities compared with 9.6% who did not. Physical activity was the most common activity reduced/ceased (48.0%) followed by sexual activity (41.2%) and social activities (37.8%). Of 16.0% of respondents with mMRC 3–4 talking on the phone was affected compared with only 2.9% of respondents with mMRC 2. Worsening breathlessness was associated with increasingly sedentary lifestyles and more limited function, those reporting reduced/ceased activities had an associated increase in reporting anxiety and depression. In adjusted analyses, breathlessness was associated with increased likelihood of activities being ceased overall as well as physical and sexual activities being affected separately.

Conclusion

Worsening breathlessness was associated with decreasing levels of self-reported physical activity, sexual activity and function. Overall, the study showed that people with persisting breathlessness modify their lifestyle to avoid it by reducing or ceasing a range of activities, seeking to minimise their exposure to the symptom.

Dyspnoea-12 and Multidimensional Dyspnea Profile: Systematic Review of Use and Properties

CONTEXT

The Dyspnoea-12 (D-12) and Multidimensional Dyspnea Profile (MDP) were specifically developed for assessment of multiple sensations of breathlessness.

OBJECTIVES

This systematic review aimed to identify the use and measurement properties of the D-12 and MDP across populations, settings and languages.

METHODS

Electronic databases were searched for primary studies (2008-2020) reporting use of the D-12 or MDP in adults. Two independent reviewers completed screening and data extraction. Study and participant characteristics, instrument use, reported scores and minimal clinical important differences (MCID) were evaluated. Data on internal consistency (Cronbach's α) and test-retest reliability (intraclass correlation coefficient, ICC) were pooled using random effects models between settings and languages.

RESULTS

A total 75 publications reported use of D-12 (n = 35), MDP (n = 37) or both (n = 3), reflecting 16 chronic conditions. Synthesis confirmed two factor structure, internal consistency (Cronbach's α mean, 95% CI: D-12 Total = 0.93, 0.91-0.94; MDP Immediate Perception [IP] = 0.88, 0.85-0.90; MDP Emotional Response [ER] = 0.86, 0.82-0.89) and 14 day test-rest reliability (ICC: D-12 Total = 0.91, 0.88-0.94; MDP IP = 0.85, 0.70-0.93; MDP ER = 0.84, 0.73-0.90) across settings and languages. MCID estimates for clinical interventions ranged between -3 and -6 points (D-12 Total) with small variability in scores over 2 weeks (D-12 Total 2.8 (95% CI: 2.0 to 3.7), MDP-A1 0.8 (0.6 to 1.1) and six months (D-12 Total 2.9 (2.0 to 3.7), MDP-A1 0.8 (0.6 to 1.1)).

CONCLUSION

D-12 and MDP are widely used, reliable, valid and responsive across various chronic conditions, settings and languages, and could be considered standard instruments for measuring dimensions of breathlessness in international trials.

Multi-Dimensional Dyspnea-Related Scales Validated in Individuals With Cardio-Respiratory and Cancer Diseases. A Systematic Review of Psychometric Properties

CONTEXT

In order to examine the multi-dimensional nature of dyspnea and its impact on the activities of daily living (ADLs) in patients with cardio-respiratory and cancer diseases, validated measures are needed.

OBJECTIVES

Our aim was to identify all the multi-dimensional clinical scales assessing dyspnea and its impact on ADLs in patients with cardio-respiratory and cancer diseases, and to critically appraise their psychometric properties.

METHODS

Five databases were systematically searched up to July 2020. Eligible criteria were: the examination of at least one psychometric property, and the recruitment of adults with a cardio-respiratory or cancer disease in non-emergency settings. The characteristics and psychometric properties of the studies included were presented through a narrative synthesis. The methodological quality of the studies and evidence synthesis were rated using the "COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN)" criteria.

RESULTS

Forty-three studies, for which eight assessment scales had been identified, were included in the review. At the time of the review, three multi-dimensional assessment scales were available for assessing dyspnea symptoms, and five multi-dimensional scales were available to examine the impact of dyspnea on ADLs. Although the use of these scales has rapidly grown, evidence of psychometric properties has been reported as limited in most of the scales.

CONCLUSION

Despite the potential of the identified scales, further studies are needed to strength evidence on the validity and reliability of the multi-dimensional dyspnea scales. Furthermore, more studies appraising the content validity and responsiveness of the scales are specifically recommended.

Prevalence and severity of differing dimensions of breathlessness among elderly males in the population

Breathlessness is common in the general population. Existing data were obtained primarily with the uni-dimensional modified Medical Research Council breathlessness scale (mMRC) that does not assess intensities of unpleasantness nor physical, emotional and affective dimensions. The aim of this research was to determine the prevalence and intensity of these dimensions of breathlessness in elderly males and any associations with their duration, change over time and mMRC grade.

We conducted a population-based, cross-sectional study of 73-year-old males in a county in southern Sweden. Breathlessness was self-reported at one time point using a postal survey including the Dyspnea-12 (D-12), the Multidimensional Dyspnea Profile (MDP) and the mMRC. Presence of an increased dimension score was defined as a score ≥minimal clinically important difference for each dimension scale. Association with the mMRC, recalled change since age 65, and duration of breathlessness were analysed with linear regression.

Among 907 men, an increased dimension score was present in 17% (D-12 total score), 33% (MDP A1 unpleasantness), 19% (D-12 physical), 17% (MDP immediate perception), 10% (D-12 affective) and 17% (MDP emotional response). The unpleasantness and affective dimensions were strongly associated with mMRC≥3. Higher MDP and D-12 scores were associated with worsening of breathlessness since age 65, and higher MDP A1 unpleasantness was associated with breathlessness of less than 1 year duration.

Increased scores of several dimensions of breathlessness are prevalent in 73-year-old males and are positively correlated with mMRC scores, worsening of breathlessness after age 65, and duration of less than 1 year.

This first epidemiological study of multidimensional breathlessness shows that unpleasant, physical, affective and emotional experiences of breathlessness are common among elderly males, and are strongly associated with mMRC ≥3https://bit.ly/3EThp5a

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 dimensions association with physical and mental quality of life: the population based VASCOL study of elderly men

Background

Breathlessness is a multidimensional symptom prevalent in elderly affecting many aspects of life. We aimed to determine how different dimensions of breathlessness are associated with physical and mental quality of life (QoL) in elderly men.

Methods

This was a cross-sectional, population-based analysis of 672 men aged 73 years in a Swedish county. Breathlessness was assessed using Dyspnoea-12 (D-12) and Multidimensional Dyspnoea Profile (MDP), and QoL using the Short Form 12 physical and mental scores. Scores were compared as z-scores across scales and analysed using multivariable linear regression, adjusted for smoking, body mass index and the presence of respiratory and cardiovascular disease.

Results

Worse breathlessness was related to worse physical and mental QoL across all the D-12 and MDP dimension scores. Physical QoL was most strongly associated with perceptional breathlessness scores, D-12 total and physical scores (95% CI −0.45 to −0.30). Mental QoL was more strongly influenced by affective responses, MDP emotional response score (95% CI −0.61 to −0.48). Head-to-head comparison of the instruments confirmed that D-12 total and physical scores most influenced physical QoL, while mental QoL was mostly influenced by the emotional responses captured by the MDP.

Conclusion

Breathlessness dimensions and QoL measures are associated differently. Physical QoL was most closely associated with sensory and perceptual breathlessness dimensions, while emotional responses were most strongly associated with mental QoL in elderly men. D-12 and MDP contribute complimentary information, where affective and emotional responses may be related to function, deconditioning and QoL.

Reliability and validity of the multidimensional dyspnea profile in hospitalized Chinese patients with respiratory diseases

Background:

Dyspnea is a multidimensional experience similar to pain and is one of the most common clinical presentations in patients with respiratory diseases. Accurately evaluating the experience of dyspnea allows nurses and physicians to deliver better medical services to patients. The multidimensional dyspnea profile emphasizes the psychosocial factors of dyspnea and assesses immediate discomfort, sensory qualities, and the emotional responses of patients with dyspnea. At present, the validity, reliability, and test–retest reliability of the multidimensional dyspnea profile in patients with respiratory diseases in China are unclear.

Objectives:

The aim of this study was to investigate the validity, reliability, and test–retest reliability of the Chinese version of the multidimensional dyspnea profile and to assess the convergent validity between the Chinese version of the multidimensional dyspnea profile and the modified Medical Research Council Dyspnea Scale.

Methods:

The factorial construct, intraclass correlations, internal consistency, and convergent validity of the Chinese version of the multidimensional dyspnea profile was evaluated using data from 231 inpatients with dyspnea from the respiratory department of a hospital. In the principal component analysis stage, 131 inpatients were evaluated. In the test–retest reliability analysis stage, 50 out of the 131 patients responded to the questionnaire again. In the confirmatory factor analysis, 100 inpatients from an independent sample were assessed.

Results:

The principal component analysis showed that the Chinese version of the multidimensional dyspnea profile had a two-factor structure: the immediate perceptual-related problem factor (6 items) and the emotional response-related problem factor (5 items). The convergent validity between the Chinese version of the multidimensional dyspnea profile and the modified Medical Research Council Dyspnea Scale was significant and acceptable based on the average variance extracted (r = .56, p < .001). The confirmatory factor analysis revealed a good model fit and provided support for the construct validity of the Chinese version of the multidimensional dyspnea profile. Overall, the internal consistency and intraclass correlation coefficient of the Chinese version of the multidimensional dyspnea profile were good.

Conclusion:

The 11-item Chinese version of the multidimensional dyspnea profile has acceptable validity and reliability in patients with respiratory diseases in China. In the future, more studies should be performed to further explore its clinical application.

VAScular and Chronic Obstructive Lung disease (VASCOL): a longitudinal study on morbidity, symptoms and quality of life among older men in Blekinge county, Sweden

PURPOSE

Despite data showing breathlessness to be more prevalent in older adults, we have little detail about the severity or multidimensional characteristics of breathlessness and other self-reported measures (such as quality of life and other cardiorespiratory-related symptoms) in this group at the population level. We also know little about the relationship between multidimensional breathlessness, other symptoms, comorbidities and future clinical outcomes such as quality of life, hospitalisation and mortality. This paper reports the design and descriptive findings from the first two waves of a longitudinal prospective cohort study in older adults.

PARTICIPANTS

Between 2010 and 2011, 1900 men in a region in southern Sweden aged 65 years were invited to attend for VAScular and Chronic Obstructive Lung disease (VASCOL) baseline (Wave 1) assessments which included physiological measurements, blood sampling and a self-report survey of lifestyle and previous medical conditions. In 2019, follow-up postal survey data (Wave 2) were collected with additional self-report measures for breathlessness, other symptoms and quality of life. At each wave, data are cross-linked with nationwide Swedish registry data of diseases, treatment, hospitalisation and cause of death.

FINDINGS TO DATE

1302/1900 (68%) of invited men participated in Wave 1, which include 56% of all 65-year-old men in the region. 5% reported asthma, 2% chronic obstructive pulmonary disease, 56% hypertension, 10% diabetes and 19% had airflow limitation. The VASCOL cohort had comparable characteristics to those of similarly aged men in Sweden. By 2019, 109/1302 (8.4%) had died. 907/1193 (76%) of the remainder participated in Wave 2. Internal data completeness of 95% or more was achieved for most Wave 2 measures.

FUTURE PLANS

A third wave will be conducted within 4 years, and the cohort will be followed through repeated follow-ups planned every fourth year, as well as national registry data of diagnosis, treatments and cause of death.

How to Assess Breathlessness in Chronic Obstructive Pulmonary Disease

Activity-related breathlessness is the most problematic symptom of chronic obstructive pulmonary disease (COPD), arising from complex interactions between peripheral pathophysiology (both pulmonary and non-pulmonary) and central perceptual processing. To capture information on the breathlessness experienced by people with COPD, many different instruments exist, which vary in applicability depending on the purpose and context of assessment. We reviewed common breathlessness assessment instruments, providing recommendations around how to assess the severity of, or change in, breathlessness in people with COPD in daily life or in response to exercise provocation. A summary of 14 instruments for the assessment of breathlessness severity in daily life is presented, with 11/14 (79%) instruments having established minimal clinically importance differences (MCIDs) to assess and interpret breathlessness change. Instruments varied in their scope of assessment (functional impact of breathlessness or the severity of breathlessness during different activities, focal periods, or alongside other common COPD symptoms), dimensions of breathlessness assessed (uni-/multidimensional), rating scale properties and intended method of administration (self-administered versus interviewer led). Assessing breathlessness in response to an acute exercise provocation overcomes some limitations of daily life assessment, such as recall bias and lack of standardized exertional stimulus. To assess the severity of breathlessness in response to an acute exercise provocation, unidimensional or multidimensional instruments are available. Borg's 0-10 category rating scale is the most widely used instrument and has estimates for a MCID during exercise. When assessing the severity of breathlessness during exercise, measures should be taken at a standardized submaximal point, whether during laboratory-based tests like cardiopulmonary exercise testing or field-based tests, such as the 3-min constant rate stair stepping or shuttle walking tests. Recommendations are provided around which instruments to use for breathlessness assessment in daily life and in relation to exertion in people with COPD.

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

A common model for the breathlessness experience across cardiorespiratory disease

Chronic breathlessness occurs across many different conditions, often independently of disease severity. Yet, despite being strongly linked to adverse outcomes, the consideration of chronic breathlessness as a stand-alone therapeutic target remains limited. Here we use data-driven techniques to identify and confirm the stability of underlying features (factors) driving breathlessness across different cardiorespiratory diseases. Questionnaire data on 182 participants with main diagnoses of asthma (21.4%), COPD (24.7%), heart failure (19.2%), idiopathic pulmonary fibrosis (18.7%), other interstitial lung disease (2.7%), and "other diagnoses" (13.2%) were entered into an exploratory factor analysis (EFA). Participants were stratified based on their EFA factor scores. We then examined model stability using 6-month follow-up data and established the most compact set of measures describing the breathlessness experience. In this dataset, we have identified four stable factors that underlie the experience of breathlessness. These factors were assigned the following descriptive labels: 1) body burden, 2) affect/mood, 3) breathing burden and 4) anger/frustration. Stratifying patients by their scores across the four factors revealed two groups corresponding to high and low burden. These two groups were not related to the primary disease diagnosis and remained stable after 6 months. In this work, we identified and confirmed the stability of underlying features of breathlessness. Previous work in this domain has been largely limited to single-diagnosis patient groups without subsequent re-testing of model stability. This work provides further evidence supporting disease independent approaches to assess breathlessness.

Validity and reliability of the Turkish version of the Multidimensional Dyspnea Profile in outpatients with respiratory disease

Background/aim

Dyspnea is the subjective feeling of breathing discomfort, which is a significant problem for patients with heart and respiratory disease and also an important determinant of exercise tolerance, quality of life, and mortality in various diseases. Most of the scales are not enough to investigate the multidimensional effects of dyspnea; therefore, the Multidimensional Dyspnea Profile (MDP) was developed and validated in many languages. This study aimed to translate and culturally adapt the MDP into Turkish and investigate the psychometric properties of this adapted version in outpatients with respiratory disease.

Materials and methods

The MDP was translated and culturally adapted into Turkish following published guidelines. A total of 170 outpatients with respiratory disease were included to assess psychometric properties. The factorial structure was investigated using a principal component analysis. Two situations were used in this study evaluating dyspnea in activity-related and resting conditions. We formulated 17 hypotheses for each MDP domain (in total 68) to assess construct validity, and correlations were investigated between the MDP and measures of body mass index, pulmonary function test, other dyspnea assessments, anxiety, depression, and health-related quality of life. To investigate the test-retest reliability, the MDP was administered again after 1-h and 1 week.

Results

Internal consistency of the MDP was excellent (Cronbach’s alpha coefficients ranged from 0.89 to 0.93). The exploratory factor analysis revealed 2 components explaining a 70% and 76% variance. Overall, 64 of the 68 predetermined hypotheses (94%) were confirmed to test construct validity. The MDP showed excellent test-retest reliability for a 1-hperiod (intraclass correlation coefficient values ranged from 0.98 to 0.99). However, test-retest reliability decreased moderate-to-high after 1 week (0.53–0.80).

Conclusion

The MDP was successfully translated and culturally adapted into Turkish and this version showed good psychometric properties including the factorial structure, internal consistency, test-retest reliability, and construct validity to assess multidimensional aspects of dyspnea.

Minimal Clinically Important Differences and Feasibility of Dyspnea-12 and the Multidimensional Dyspnea Profile in Cardiorespiratory Disease

CONTEXT

Breathlessness is a cardinal symptom in cardiorespiratory disease and consists of multiple dimensions that can be measured using the instruments Dyspnea-12 (D12) and the Multidimensional Dyspnea Profile (MDP).

OBJECTIVES

The objective of the study is to determine the minimal clinically important differences (MCIDs) of all D12 and MDP summary and subdomain scores as well as the instruments' feasibility in patients with cardiorespiratory disease.

METHODS

Prospective multicenter cohort study of outpatients with diagnosed cardiorespiratory disease and breathlessness in daily life. D12 and MDP were assessed at baseline, after 30-90 minutes and two weeks. MCIDs were calculated using anchor-based and distributional methods for summary and subdomain scores. Feasibility was assessed as rate of missing data, help required, self-reported difficulty, and completion time.

RESULTS

A total 182 outpatients (53.3% women) were included; main diagnoses were chronic obstructive pulmonary disease (COPD; 25%), asthma (21%), heart failure (19%), and idiopathic pulmonary fibrosis (19%). Anchor-based MCIDs were for D12 total score 2.83 (95% CI 1.99-3.66); D12 physical 1.81 (1.29-2.34); D12 affective 1.07 (0.64-1.49); MDP A1 unpleasantness 0.82 (0.56-1.08); MDP perception 4.63 (3.21-6.05), and MDP emotional score 2.37 (1.10-3.64). The estimates were consistent with small-to-moderate effect sizes using distributional analysis, and MCIDs were similar between COPD and non-COPD patients. The instruments were generally feasible and quick to use.

CONCLUSION

D12 and MDP are responsive to change and feasible for use for assessing multidimensional breathlessness in outpatients with cardiorespiratory disease. MCIDs were determined for use as endpoints in clinical trials.

A physiological approach to understand the role of respiratory effort in the progression of lung injury in SARS-CoV-2 infection

Deterioration of lung function during the first week of COVID-19 has been observed when patients remain with insufficient respiratory support. Patient self-inflicted lung injury (P-SILI) is theorized as the responsible, but there is not robust experimental and clinical data to support it. Given the limited understanding of P-SILI, we describe the physiological basis of P-SILI and we show experimental data to comprehend the role of regional strain and heterogeneity in lung injury due to increased work of breathing.

In addition, we discuss the current approach to respiratory support for COVID-19 under this point of view.

Episodic Breathlessness with and without Background Dyspnea in Advanced Cancer Patients Admitted to an Acute Supportive Care Unit

Aim: To characterize episodic breathlessness (EB) in patients with advanced cancer, and to determine factors influencing its clinical appearance. Methods: A consecutive sample of advanced cancer patients admitted to an acute palliative care unit was surveyed. Continuous dyspnea and EB were measured by a numerical scale. The use of drugs used for continuous dyspnea and EB was recorded. Patients were asked about the characteristics of EB (frequency, intensity, duration and triggers). The Multidimensional dyspnea profile (MDP), the Brief dyspnea inventory (BDI), the Athens sleep scale (AIS) and the Hospital Anxiety and Depression Scale (HADS) were also administered. Results: From 439 advanced cancer patients surveyed, 34 and 27 patients had EB, without and with background dyspnea, respectively. The mean intensity and the number of episodes were higher in patients with background dyspnea (p < 0.0005 and p = 0.05, respectively). No differences in duration were observed. Most episodes lasted <10 min. A recognizable cause triggering EB was often found. The presence of both background dyspnea and EB was associated with higher values of MDP and BDI. EB was independently associated with frequency and intensity of background dyspnea (OR = 20.9, 95% CI (Confidence interval) 9.1–48.0; p < 0.0005 and OR = 1.97, 95% CI 1.09–3.58; p = 0.025, respectively) and a lower Karnofsky level (OR = 0.96, 95%CI 0.92–0.98, p = 0.05). Discussion: EB may occur in patients with and without continuous dyspnea, and is often induced by physical and psychological factors. EB intensity is higher in patients with continuous dyspnea. The duration was often so short that the use of drugs, as needed, may be too late, unless administered pre-emptively when the trigger was predictable.