# Short and long-term prognosis of hospitalization for dyspnoea based on aetiology and hospitalization ward: insights from the PARADISE cohort

Guillaume Baudry, Claire Lacomblez, Emmanuel Bresso, Luca Monzo, Alexandre Mebazaa, Kevin Duarte, Déborah Jaeger, Adrien Bassand, Aurélien Buessler, Gaetan Giacomin, et al.

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## ► To cite this version:

Guillaume Baudry, Claire Lacomblez, Emmanuel Bresso, Luca Monzo, Alexandre Mebazaa, et al. Short and long-term prognosis of hospitalization for dyspnoea based on aetiology and hospitalization ward: insights from the PARADISE cohort. European Journal of Heart Failure, 2026, Online ahead of print. 10.1093/ejhf/xuaf027. hal-05536979

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Submitted on 4 Mar 2026

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# Short and long-term prognosis of hospitalization for dyspnoea based on aetiology and hospitalization ward: insights from the PARADISE cohort

Guillaume Baudry ID 1,2,3, Claire Lacomblez 1,2, Emmanuel Bresso ID 1,2, Luca Monzo ID 1,2, Alexandre Mebazaa ID 4,5,6, Kevin Duarte 1,2, Déborah Jaeger 7,8,9, Adrien Bassand 8,9, Aurélien Buessler 8,9, Gaetan Giacomin 8,9, Charlène Duchanois 8,9, Torgny Wessman 10,11, Faiez Zannad ID 1,2, Tahar Chouihed 1,2,8,9, and Nicolas Girerd ID 1,2,*

Received 10 June 2025; revised 4 November 2025; accepted 25 November 2025; online publish-ahead-of-print 22 January 2026

## Abstract

### Aims

Dyspnoea accounts for nearly 5% of emergency department (ED) visits. Our aim was to describe the in-hospital and long-term outcomes of patients admitted to the ED for dyspnoea, based on their underlying aetiology, and to determine if prognosis varies according to the hospitalization setting.

### Methods

We analyzed 18 903 consecutive patients (48% male, average age 73 years) hospitalized after an ED visit for dyspnoea from January 2010 to December 2019, as part of the PARADISE cohort (PAthwAy of Dyspneic patient in Emergency—NCT02800122). Dyspnoea causes were classified as acute heart failure (AHF), respiratory infection (RI), chronic obstructive pulmonary disease (COPD), pulmonary embolism (PE), or asthma.

### Results

RI (30%), AHF (28%), and COPD (13%) were the predominant discharge diagnoses. In-hospital mortality stood at 12% overall, ranging from 1.1% in asthma to 15% in AHF and RI. Five-year all-cause mortality for patients discharged alive was 75% in AHF, 66% in RI, 62% in COPD, 37% in PE, and 26% in asthma. Hospitalization in specialized wards was associated with significantly reduced in-hospital mortality across all aetiologies, and with a decreased long-term mortality for RI and AHF (adjusted-HR 0.90, 95% CI 0.82–0.99, P = 0.02 for RI and adjusted-HR 0.90, 95% CI 0.82–0.99, P = 0.03 for AHF).

### Conclusion

Patients hospitalized for dyspnoea face a high-risk of mortality both in-hospital and post-discharge. In view of the strikingly high mortality in dyspneic patients and the potential benefits of specialized management, our study calls for rapidly setting up personalized in-hospital and post-discharge dyspnoea pathways.

<footnote n="1">¹Université de Lorraine, INSERM, Centre d'Investigation Clinique Plurithématique 1433, Inserm U1116, CHRU de Nancy, Nancy, France; ²INI-CRCT (Cardiovascular and Renal Clinical Trialists) F-CRIN Network, Nancy, France; ³REICATRA, Recherche et Enseignement en IC Avancée, Transplantation, Assistance, Vandœuvre-lès-Nancy, France; ⁴University of Paris Cité, Paris, France; ⁵Inserm UMR-S 942, Cardiovascular Markers in Stress Conditions (MASCOT), Paris, France; ⁶Department of Anaesthesiology, Critical Care, Lariboisière—Saint-Louis Hospitals, DMU Parabol, AP-HP Nord, Paris, France; ⁷INSERM U1116, Défaillance Cardiovasculaire Aiguë et Chronique, University of Lorraine, Vandœuvre-lès-Nancy 54500, France; ⁸Emergency Department, University Hospital of Nancy, France; ⁹INSERM U1116, University of Lorraine, Nancy, France; ¹⁰Department of Clinical Sciences Malmö, Lund University, Sweden; and ¹¹Department of Emergency Medicine, Skane University Hospital, Malmö, Sweden</footnote>

<footnote>* Corresponding author. Email: n.girerd@chru-nancy.fr</footnote>

<footnote>© The Author(s) 2026. Published by Oxford University Press on behalf of the European Society of Cardiology.</footnote>

<footnote>This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.</footnote>
## Graphical Abstract

### Short and Long-Term Prognosis of Hospitalization for Dyspnea Based on Etiology and Hospitalization Ward: Insights from the PARADISE Cohort

All-cause mortality stratified by dyspnea etiology in patients surviving to discharge following emergency department visits

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18903 consecutive patients hospitalized after an emergency department admission for dyspnea

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January 2010 to December 2019

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52%

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73 years

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PARADISE cohort NCT02800122

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<table><thead><tr><th>Diagnoses</th><th>1 year mortality</th><th>3 years mortality</th><th>5 years mortality</th></tr></thead><tbody><tr><td>Acute heart failure</td><td>42%</td><td>63%</td><td>75%</td></tr><tr><td>Respiratory infection</td><td>39%</td><td>57%</td><td>66%</td></tr><tr><td>Chronic obstructive pulmonary disease</td><td>27%</td><td>49%</td><td>62%</td></tr><tr><td>Asthma</td><td>7.7%</td><td>19%</td><td>26%</td></tr><tr><td>Pulmonary embolism</td><td>19%</td><td>28%</td><td>37%</td></tr><tr><td>All other discharge diagnoses</td><td>33%</td><td>46%</td><td>54%</td></tr></tbody></table>

Risk of in-hospital mortality and post-discharge mortality according to dyspnea etiology and hospitalization units of care

<table><thead><tr><th>Diagnosis</th><th>Units</th><th>In hospital mortality</th><th>OR (95% CI)</th><th>p-value</th></tr></thead><tbody><tr><td rowspan="2">Acute heart failure</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>0.25 (0.19, 0.33)</td><td>&lt;0.01</td></tr><tr><td rowspan="2">Respiratory infection</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>0.71 (0.59, 0.87)</td><td>&lt;0.01</td></tr><tr><td rowspan="2">Chronic obstructive pulmonary disease</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>0.47 (0.28, 0.78)</td><td>&lt;0.01</td></tr><tr><td rowspan="2">Asthma</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>Reference</td><td></td></tr><tr><td rowspan="2">Pulmonary embolism</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>0.07 (0.01, 0.81)</td><td>0.03</td></tr></tbody></table>

<table><thead><tr><th>Diagnosis</th><th>Units</th><th>Post discharge mortality</th><th>HR (95% CI)</th><th>p-value</th></tr></thead><tbody><tr><td rowspan="2">Acute heart failure</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>0.9 (0.82, 0.99)</td><td>0.03</td></tr><tr><td rowspan="2">Respiratory infection</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>0.9 (0.82, 0.99)</td><td>0.02</td></tr><tr><td rowspan="2">Chronic obstructive pulmonary disease</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>0.96 (0.83, 1.12)</td><td>0.63</td></tr><tr><td rowspan="2">Asthma</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>2.05 (1.04, 4.05)</td><td>0.04</td></tr><tr><td rowspan="2">Pulmonary embolism</td><td>General care</td><td></td><td>Reference</td><td></td></tr><tr><td>Specialized care</td><td></td><td>1.09 (0.70, 1.70)</td><td>0.69</td></tr></tbody></table>

* The five-year mortality rate exceeds 60% for patients with acute heart failure, respiratory infections, and chronic obstructive pulmonary disease.

* Patients hospitalized for dyspnea face a high risk of mortality, both during hospitalization and after discharge.

* Admission to a specialized care unit is associated with lower in-hospital mortality across multiple etiologies and a reduced long-term mortality risk for conditions such as acute heart failure and respiratory infections.

In-hospital and post-discharge prognosis of patients hospitalized for dyspnoea after emergency department admission, based on aetiology and hospitalization ward. Among 18 903 patients from the PARADISE cohort, acute heart failure, respiratory infection, and chronic obstructive pulmonary disease were associated with the highest in-hospital and 5-year mortality rates. Admission to specialized care units, compared with general care wards, was associated with a significantly lower risk of in-hospital mortality across most aetiologies and with reduced long-term mortality for acute heart failure and respiratory infections. COPD, Chronic obstructive pulmonary disease.

## Keywords

Dyspnoea • Emergency department • Heart failure • Respiratory infection • COPD

## Evidence Before This Study

Prior research has mainly focused on the in-hospital prognosis of patients with specific dyspnoea causes, such as acute heart failure (AHF), respiratory infection (RI), and chronic obstructive pulmonary disease (COPD) decompensation, who were admitted to the emergency department (ED). However, not all of these patients necessarily presented with dyspnoea. Additionally, these studies often did not examine patients admitted primarily for dyspnoea, irrespective of their underlying condition. There is a notable lack of comprehensive data on both in-hospital and long-term mortality associated with various causes of dyspnoea. Many of these studies exhibit a moderate risk of bias and fail to analyze long-term outcomes. This situation underscores a significant gap in our understanding of the short- and long-term prognoses following hospital admissions for dyspnoea, especially in relation to the type of hospitalization (specialized vs not specialized management). This gap highlights the need for more inclusive and extensive research in this area.

## Added Value of This Study

This study, using data from the PARADISE cohort, provides a unique perspective by evaluating both in-hospital and long-term mortality across a range of dyspnoea causes. It offers an exhaustive and comprehensive view of the prognosis for patients hospitalized for dyspnoea, considering both the aetiology and the context of hospitalization. This study was able to investigate the association of specialized ward hospitalization on outcomes, providing new insights into optimal patient management strategies.

## Implications of All the Available Evidence

Our findings underscore the substantial risk of both in-hospital and post-discharge mortality among patients hospitalized with dyspnoea, regardless of its underlying cause. The study indicates a significant enhancement in outcomes when patients receive care in specialized units. These insights advocate for a paradigm shift in dyspnoea management within emergency settings, emphasizing the need for personalized in-hospital and post-discharge dyspnoea pathways to optimize ward placement. Similar to the establishment of 'chest pain units,' there is a pressing need to develop and evaluate 'dyspnoea units' to improve management and prognosis.
# Introduction

Described initially as 'an uncomfortable sensation of breathing',¹ dyspnoea was recently defined by the American Thoracic Society as 'a subjective experience of breathing discomfort that comprises qualitatively distinct sensations that vary in intensity, in their unpleasantness and in their emotional and behavioural significance'.² Dyspnoea accounts for more than 5% of all consultations in the emergency departments³,⁴ and is observed in half of all patients consulting for an acute condition in tertiary hospitals.² The main causes of acute dyspnoea are cardiopulmonary, namely acute heart failure (AHF), pulmonary embolism (PE), respiratory infection (RI), decompensation of chronic obstructive pulmonary disease (COPD), and asthma. These underlying diseases are major public health issues, accounting for a substantial number of hospitalizations and in-hospital deaths. In addition, following the index hospitalization, patients discharged from an AHF-, RI- and COPD- related hospitalizations are often readmitted within 30 days.⁵,⁶

Dyspnoea is an independent predictor of mortality in COPD and patients with heart disease.⁷ Given that dyspnoea represents a heterogeneous cause of emergency department (ED) visits, epidemiological data and information on its overall prognosis are scarce.⁸ In addition, current data are often limited to the index hospitalization whereas the long-term prognosis of patients admitted for dyspnoea has been poorly studied. Most epidemiological studies actually reported the in-hospital prognosis of 'individual' aetiologies of dyspnoea rather than the overall (short and long-term) prognosis of the broad spectrum of patients admitted for dyspnoea.⁹,¹⁰

The objective of the present study was to characterize the clinical profile of the broad spectrum of patients admitted for dyspnoea in the ED, both overall and according to the main underlying aetiologies. We also aimed to assess in-hospital and long-term mortality following an admission for dyspnoea, according to age and hospitalization setting (hospital ward, acute care or specialized ward) after the emergency room visit.

# Methods

## Participants

The study population included all patients hospitalized after a visit to the ED of the Nancy University Hospital with signs of dyspnoea from 1 January 2010, to 31 December 2019, and corresponding to a pre-COVID period. Among the 27 606 patients admitted during this period, 8703 (31.5%) were not hospitalized or did not have a discharge diagnosis and were thus excluded from the study. The final cohort included 18 903 patients.

## Data collection and validation

Clinical data, cardiovascular and non-cardiovascular comorbidities, usual treatment, treatment received before hospital admission and laboratory results were extracted from institutional medical records. A combination of an ontology-driven method and deep learning natural language processing was used to translate the information from institutional medical records into variables that could be analyzed (Supplementary Materials). Variables extracted with this automatic method which had an F-score of 0.75 or higher in a validation dataset were retained for the analysis. Discharge diagnosis was derived from the inpatients coding (primary and secondary diagnoses) of the index hospitalization. The main diagnosis was retained as aetiology of dyspnoea if it corresponded to one of the 5 following aetiologies: AHF, respiratory infections, COPD, PE, or asthma. If the cause of dyspnoea was not classified following this first step, secondary diagnoses were investigated, with aetiology determined according to the following hierarchical order: AHF > COPD > asthma > respiratory infections > PE. Following this second step, patients not classified into one of these five categories were grouped into the

'all other discharge diagnoses' (AODD) category (see Supplementary data online, Figure S1).

The study was approved by the Commission nationale de l'informatique et des libertés (CNIL) and Comité d'Expertise pour les Recherches, les Etudes et les Evaluations dans le domaine de la Santé (CERESS).

## Outcomes

The primary outcome was in-hospital mortality. Death status and date of death were obtained from hospital data for in-hospital deaths and from the French National Institute of Statistics and Economic Studies (INSEE) for post-discharge death.

Secondary outcome was five-year mortality for patients discharged alive from the index hospitalization.

## Classification of hospital departments

The departments in which patients were hospitalized were classified according to the following hierarchical order:

1. Intensive care unit (at least one stay in intensive or critical care unit).

2. Specialized care unit (at least one stay in a department specialized in the management of the index disease).

3. General care unit (patients hospitalized in other departments).

The specialized units comprised the pulmonology and infectious diseases departments for RI, the cardiology department for AHF, the cardiology and pulmonology departments for PE, the pulmonology department for COPD, and the pulmonology and allergy and immunology departments for asthma.

Patients hospitalized in intensive care units were excluded from the in-hospital and long-term mortality analyses, due to their severity profiles compared with patients in conventional wards.

## Statistical analyses

Categorical variables were presented as frequencies (%) and percentages while numerical variables were expressed as mean (standard deviation). To investigate differences in between-group characteristics and prognosis according to dyspnoea aetiology, categorical variables were compared using the $\chi^2$ test and continuous variables with Mann-Whitney non-parametric tests.

Kaplan-Meier curves were plotted to describe the occurrence of all-cause mortality in the whole population and in patients discharged alive and compared using the log-rank test.

Associations between the main diagnoses at discharge and in-hospital mortality were assessed by multivariable logistic regression analyses. Variables ($N = 62$) with less than 10% missing values were used as candidate covariates including demographics, medical history, medications or treatment and medical characteristics at baseline and discharge (see Supplementary data online, Table S1). Adjusted odds ratio and 95% confidence intervals (CI) for the binary outcome of in-hospital all-cause mortality were estimated.

The associations between the main diagnoses at discharge and long-term all-cause mortality were assessed using Cox proportional hazards regression models adjusted on 62 previously described variables. Backward selection was performed using the Akaike information criterion (AIC). Hazard ratios (HRs) and 95% CI were estimated.

A sensitivity analysis was conducted to assess the association between hospitalization in specialized care or intensive care units and mortality, while accounting for patients' medical history. This analysis aimed to evaluate the effect of hospitalization in specialized care units independently of care pathways or referral patterns. Patients with a medical history were defined as those having at least one of the following conditions: atrial fibrillation, heart disease, heart failure, pulmonary embolism, asthma, or COPD. In addition, a propensity score for the probability of hospitalization in a specialized versus a general unit was calculated, and inverse probability of treatment weighting (IPTW) was applied to further adjust for potential differences in baseline characteristics. To limit the influence of extreme values, weights were truncated at the 1st and 99th percentiles.

In order to assess the homogeneity of associations according to age, the population was divided into 3 age tertiles, namely less under 60 years old, between 60 and 80 years old and over 80 years old. In-hospital and long-
term mortality was also assessed according to hospital department hospitalization after the emergency visit.

Statistical analyses of this study were carried out using the R program version 4.2.1.

# Results

## Characteristics according to dyspnoea aetiology

Among the 18 903 patients hospitalized with dyspnoea, more than half were diagnosed with RI (N = 5585, 30%) or AHF (N = 5305, 28%) (Table 1). COPD (N = 2477, 13%), PE (N = 678, 4%), and asthma (N = 453, 2%) were less frequent. The cause of dyspnoea did not fall under any of the five previously mentioned diagnoses (categorized as AODD) in 4405 patients (23.3%).

Patients were predominantly elderly (mean age 73 ± 17 years) particularly those with AHF (80 ± 12 years). Overall, half of the patients were male (48%) with a male predominance for COPD (64%) and a female predominance for asthma (70%). Cardiovascular comorbidities (hypertension, diabetes mellitus, dyslipidemia) differed between groups (P < 0.0001 for all), with asthma patients having the fewest comorbidities and patients with AHF having the most.

Creatinine, bilirubin, transaminases, and BNP were higher and haemoglobin, haematocrit, and proteins lower in AHF (P < 0.0001 for all). Leukocytes and C-reactive protein (CRP) were higher in RI compared with other groups (P < 0.001).

## Hospitalization units according to dyspnoea aetiology

Around one patient out of four was hospitalized in an intensive care unit for AHF, PE and COPD after being treated in the ED whereas the rate was around 15% for RI and asthma. Less than one patient out of 2 was hospitalized in a specialized unit irrespective of the disease and this proportion decreased to 26% for AHF. Patients hospitalized in general care units had a median length of stay of 5 days (Q1: 1, Q3: 11), whereas those admitted to specialized care units stayed a median of 8 days (Q1: 5, Q3: 12; P < 0.001, Wilcoxon rank-sum test).

## In-hospital mortality according to dyspnoea aetiology and age

A total of 2354 patients died during their hospital stay, representing 12% in-hospital mortality. In-hospital deaths were higher in the AHF and RI groups (15% for both) comparatively to the COPD, PE and asthma groups (6.2%, 5.5% and 1.1%, respectively, P < 0.001, Figure 1A). A sex-stratified analysis is presented in Supplementary data online, Figure S2.

Using RI as reference, the risk of in-hospital mortality was not significantly different (adjusted OR: 1.03 [0.91–1.17], P = 0.61) for AHF whereas it was lower for PE (adjusted OR: 0.57 [0.39–0.80], P = 0.002), COPD (adjusted OR: 0.47 [0.38–0.57], P < 0.001), and asthma (adjusted OR: 0.19 [0.07–0.42], P < 0.001; Figure 2A).

In-hospital mortality increased gradually with age for all dyspnoea aetiologies except in AHF patients in whom mortality was similar across all age groups (~15%, Figure 1B).

## Long-term mortality according to dyspnoea aetiology and age

With regard to long-term mortality, 11 205 patients (59%) died during a mean follow-up of 2.5 years (±2.6). At 5-years, over 50% of patients discharged alive with AHF, RI or COPD had died (respectively 71%, 60%, 59%). Five-year all-cause mortality was lower after PE or

asthma (respectively 33% and 25%, P across groups < 0.001, Figures 1A, 3A and 3B).

Using RI as reference, the risk of long-term mortality did not significantly differ in patients discharged alive following AHF (adjusted HR: 1.01 [0.95–1.08], P = 0.66). In contrast, long-term mortality was lower for COPD (adjusted HR: 0.88 [0.81–0.95], P < 0.01), PE (adjusted HR: 0.60 [0.52–0.70], P < 0.01) and asthma (adjusted HR: 0.65 [0.53–0.81], P < 0.01).

Long-term all-cause mortality increased gradually with increasing age irrespective of dyspnoea aetiology (P < 0.0001 for all, Figure 3B). Of note, 5-year mortality exceeded 35% following discharge for AHF in patients 60 years or younger.

## Mortality according to hospitalization units

Using hospitalization in a general care unit as reference, hospitalization in a specialized care unit was associated with a significant decreased risk of in-hospital mortality for AHF (adjusted OR: 0.25 [0.19–0.33], P < 0.01), RI (adjusted OR: 0.71 [0.59–0.87], P < 0.01), PE (adjusted OR: 0.07 [0.01–0.61], P = 0.03) and COPD (adjusted OR: 0.47 [0.28–0.78], P = 0.01) illustrated in Figure 2B. Results from the IPTW sensitivity analysis were consistent with those obtained in the main model (see Supplementary data online, Figure S3).

The long-term mortality risk of patients admitted in a specialized care ward (vs. general care) was associated with a 10% reduction of long-term mortality for AHF (adjusted HR: 0.90 [0.82–0.99], P = 0.03) and RI (adjusted HR: 0.90 [0.82–0.99], P = 0.02) whereas patients with asthma experienced a doubling of their risk (adjusted HR: 2.05 [1.04–4.05], P = 0.04; Figure 2B).

In a sensitivity analysis examining the overall association between hospitalization in specialized care units and prognosis, there was a 58% reduction in in-hospital mortality (adjusted OR: 0.42 [0.37–0.48], P < 0.001). This reduction was consistently observed in both patients without a medical history (adjusted OR: 0.44 [0.35–0.55], P < 0.001) and those with a medical history (adjusted OR: 0.44 [0.38–0.52], P < 0.001). These results are detailed in Supplementary data online, Table S2. Similarly, there was a 16% reduction in 1 year mortality risk (adjusted HR: 0.84 [0.78–0.91], P < 0.001). This reduction was consistently observed in both patients without a medical history (adjusted HR: 0.71 [0.62–0.83], P < 0.001) and those with a medical history (adjusted HR: 0.91 [0.83–0.99], P = 0.024).

# Discussion

Dyspnoea as a symptom upon admission to the ED is common and may indicate various underlying diseases. Our data points to the dire short and long-term prognosis of this condition. RI, AHF, and COPD diagnoses are particularly concerning, with mortality rates exceeding 12% during the initial hospitalization and 60% at 5 years. Notably, long-term mortality was exceptionally high (35% at 5 years) in patients aged 60 or younger discharged after an AHF diagnoses. Patients admitted to specialized units demonstrated a significantly improved in-hospital prognosis, even after adjusting for confounders. These results support a shift in patient management strategy, highlighting the importance of specialized unit admissions in significantly reducing mortality, regardless of the underlying disease. Moreover, conditions such as AHF and RI also benefit from this approach in terms of long-term mortality reduction.

## Epidemiology of dyspnoea

According to previous data, the average age in our study population was relatively advanced, at 73 years. Older patients have the highest rate of ED visits,¹¹ and most conditions causing dyspnoea are more prevalent with increasing age. The overall sex ratio was balanced, though the proportion of women was higher in cases of asthma and
<table><caption>**Table 1** Patient characteristics according to dyspnoea aetiology</caption><thead><tr><th rowspan="2"></th><th colspan="2">Global (n = 18 903)</th><th colspan="2">Acute heart failure (n = 5305)</th><th colspan="2">Respiratory infections (n = 5585)</th><th colspan="2">COPD (n = 2477)</th><th colspan="2">Pulmonary embolism (n = 678)</th><th colspan="2">Asthma (n = 453)</th><th colspan="2">All other diagnoses (n = 4405)</th></tr><tr><th>N</th><th>Mean ± SD/ n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/ n (%)</th><th>Mean ± SD/ n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/n (%)</th><th>Mean ± SD/n (%)</th><th>P-value</th></tr></thead><tbody><tr><td>Clinical data</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Age</td><td>18</td><td>73.39 ± 17.19</td><td>79.82 ± 11.99</td><td>74.97 ± 16.98</td><td>71.46 ± 12.61</td><td>68.20 ± 18.46</td><td>54.79 ± 22.54</td><td>67.45 ± 20.15</td><td>2080 (47.2%)</td><td>134 (29.6%)</td><td>136.73 ± 5.23</td><td>10.0001</td><td>10.0001</td><td>10.0001</td></tr><tr><td>Sex (male)</td><td>903</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Laboratory data</td><td>903</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Sodium</td><td>15</td><td>137.02 ± 5.37</td><td>137.33 ± 5.03</td><td>137.04 ± 6.03</td><td>136.49 ± 5.12</td><td>137.65 ± 3.97</td><td>137.37 ± 4.29</td><td>136.73 ± 5.23</td><td>10.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Urea</td><td>691</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>ASAT</td><td>14</td><td>0.60 ± 0.41</td><td>0.74 ± 0.48</td><td>0.59 ± 0.38</td><td>0.50 ± 0.33</td><td>0.47 ± 0.28</td><td>0.37 ± 0.22</td><td>0.53 ± 0.39</td><td>0.044</td><td>0.041</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>ALAT</td><td>508</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Bilirubin Total</td><td>5145</td><td>76.6 ± 391.6</td><td>96.6 ± 425.9</td><td>78.2 ± 471.7</td><td>54.5 ± 243.9</td><td>94.5 ± 655.8</td><td>37.1 ± 52.1</td><td>52.7 ± 109.1</td><td>0.044</td><td>0.041</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>BNP</td><td>5121</td><td>51.4 ± 227.8</td><td>63.5 ± 276.9</td><td>50.0 ± 232.7</td><td>44.6 ± 215.6</td><td>66.5 ± 314.1</td><td>31.4 ± 53.4</td><td>36.0 ± 67.2</td><td>0.041</td><td>0.041</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Creatinine</td><td>4781</td><td>14.4 ± 18.6</td><td>16.3 ± 21.3</td><td>12.7 ± 10.5</td><td>11.22 ± 9.5</td><td>12.3 ± 9.5</td><td>9.3 ± 5.2</td><td>16.8 ± 27.1</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Haemoglobin</td><td>6215</td><td>665 ± 896</td><td>1016 ± 1061</td><td>460 ± 706</td><td>263 ± 448</td><td>368 ± 570</td><td>177 ± 191</td><td>381 ± 551</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Leukocytes</td><td>13</td><td>12.4 ± 2.2</td><td>11.9 ± 2.1</td><td>12.6 ± 2.0</td><td>13.0 ± 2.1</td><td>13.1 ± 1.9</td><td>13.4 ± 1.8</td><td>12.3 ± 2.5</td><td>10.7 ± 9.6</td><td>10.5 ± 3.8</td><td>10.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Cardiovascular comorbidities</td><td>972</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Stroke</td><td>10</td><td>79.8 ± 93.8</td><td>53.2 ± 73.4</td><td>118.1 ± 107.0</td><td>71.1 ± 85.5</td><td>59.9 ± 62.5</td><td>30.2 ± 41.9</td><td>62.7 ± 83.7</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>ICD</td><td>868</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Diabetes mellitus</td><td>7737</td><td>71.5 ± 7.3</td><td>70.5 ± 7.5</td><td>71.7 ± 7.6</td><td>72.4 ± 6.6</td><td>72.1 ± 6.5</td><td>73.9 ± 5.9</td><td>71.7 ± 7.2</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Haematocrit</td><td>14</td><td>38.4 ± 6.6</td><td>37.3 ± 6.6</td><td>38.7 ± 6.1</td><td>40.5 ± 6.3</td><td>40.1 ± 5.6</td><td>40.6 ± 5.5</td><td>37.8 ± 7.3</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Haemoglobin</td><td>733</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Leukocytes</td><td>13</td><td>11.3 ± 8.4</td><td>10.5 ± 7.2</td><td>12.6 ± 9.8</td><td>11.4 ± 5.2</td><td>10.6 ± 6.2</td><td>10.5 ± 3.8</td><td>10.7 ± 9.6</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Cardiovascular comorbidities</td><td>971</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Stroke</td><td>18</td><td>3156 (16.7%)</td><td>1107 (20.9%)</td><td>1006 (18.0%)</td><td>344 (13.9%)</td><td>63 (9.3%)</td><td>35 (7.7%)</td><td>601 (13.6%)</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>ICD</td><td>903</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Diabetes mellitus</td><td>18</td><td>4555 (24.1%)</td><td>1778 (33.5%)</td><td>1173 (21.0%)</td><td>562 (22.7%)</td><td>100 (14.7%)</td><td>52 (11.5%)</td><td>890 (20.2%)</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td><td>0.0001</td></tr><tr><td>Continued</td><td>903</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>
<table><caption>**Table 1** Continued</caption><thead><tr><th></th><th>N</th><th>Global (n = 18 903)<br>Mean ± SD/<br>n (%)</th><th>Acute heart failure<br>(n = 5305)<br>Mean ± SD/n (%)</th><th>Respiratory infections<br>(n = 5585)<br>Mean ± SD/n (%)</th><th>COPD (n =<br>2477)<br>Mean ± SD/<br>n (%)</th><th>Pulmonary embolism<br>(n = 678)<br>Mean ± SD/n (%)</th><th>Asthma (n =<br>453)<br>Mean ± SD/n<br>(%)</th><th>All other discharge<br>diagnoses (n = 4405)<br>Mean ± SD/n (%)</th><th>P-value</th></tr></thead><tbody><tr><td>Dyslipidemia</td><td>18<br>903</td><td>5214 (27.6%)</td><td>1873 (35.3%)</td><td>1347 (24.1%)</td><td>711 (28.7%)</td><td>143 (21.1%)</td><td>69 (15.2%)</td><td>1071 (24.3%)</td><td>&lt;0.0001</td></tr><tr><td>Atrial<br>fibrillation</td><td>18<br>903</td><td>4429 (23.4%)</td><td>2055 (38.7%)</td><td>1117 (20.0%)</td><td>438 (17.7%)</td><td>56 (8.3%)</td><td>35 (7.7%)</td><td>728 (16.5%)</td><td>&lt;0.0001</td></tr><tr><td>Hypertension</td><td>18<br>903</td><td>9866 (52.2%)</td><td>3417 (64.4%)</td><td>2875 (51.5%)</td><td>1145 (46.2%)</td><td>305 (45.0%)</td><td>155 (34.2%)</td><td>1969 (44.7%)</td><td>&lt;0.0001</td></tr><tr><td>Pacemaker</td><td>18<br>903</td><td>1456 (7.7%)</td><td>701 (13.2%)</td><td>376 (6.7%)</td><td>136 (5.5%)</td><td>14 (2.1%)</td><td>5 (1.1%)</td><td>224 (5.1%)</td><td>&lt;0.0001</td></tr><tr><td>Heart diseases</td><td>18<br>903</td><td>5009 (26.5%)</td><td>2034 (38.3%)</td><td>1243 (22.3%)</td><td>635 (25.6%)</td><td>103 (15.2%)</td><td>47 (10.4%)</td><td>947 (21.5%)</td><td>&lt;0.0001</td></tr><tr><td>Prior HF</td><td>18<br>903</td><td>7321 (38.7%)</td><td>3497 (65.9%)</td><td>1677 (30.0%)</td><td>839 (33.9%)</td><td>101 (14.9%)</td><td>78 (17.2%)</td><td>1129 (25.6%)</td><td>&lt;0.0001</td></tr><tr><td>Non-cardiovascular comorbidities</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Asthma</td><td>18<br>903</td><td>1754 (9.3%)</td><td>310 (5.8%)</td><td>394 (7.1%)</td><td>339 (13.7%)</td><td>35 (5.2%)</td><td>403 (89.0%)</td><td>273 (6.2%)</td><td>&lt;0.0001</td></tr><tr><td>COPD</td><td>18<br>903</td><td>4876 (25.8%)</td><td>1025 (19.3%)</td><td>1157 (20.7%)</td><td>2006 (81.0%)</td><td>72 (10.6%)</td><td>86 (19.0%)</td><td>530 (12.0%)</td><td>&lt;0.0001</td></tr><tr><td>Hospitalization units</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Intensive care</td><td>—</td><td>—</td><td>1337 (25%)</td><td>845 (15%)</td><td>727 (29%)</td><td>189 (28%)</td><td>77 (17%)</td><td>—</td><td>&lt;0.0001</td></tr><tr><td>Specialized care</td><td>—</td><td>—</td><td>1381 (26%)</td><td>1868 (33%)</td><td>875 (35%)</td><td>263 (39%)</td><td>198 (44%)</td><td>—</td><td>—</td></tr><tr><td>General care</td><td>—</td><td>—</td><td>2587 (49%)</td><td>2872 (51%)</td><td>875 (35%)</td><td>226 (33%)</td><td>178 (39%)</td><td>—</td><td>—</td></tr></tbody></table>

ASAT, aspartate aminotransferase; ALAT, alanine aminotransferase; BNP, brain natriuretic peptides; COPD, chronic obstructive pulmonary disease; CRP, C-reactive protein; HF, heart failure; ICD, Implantable cardioverter defibrillators.
<figure><img src="image_9.png" /><figcaption>**Figure 1** Proportion of in-hospital and long-term mortality according to dyspnoea aetiology (A) and in-hospital mortality according to dyspnoea aetiology and age subgroups (B). \*\*\*P ≤0.001, \*\*P ≤0.01, \*P ≤0.05, NS, not significant</figcaption></figure>

PE, and lower in COPD. The five main diagnoses commonly associated with acute dyspnoea (RI, AHF, COPD, PE, and asthma) accounted for 77% of patients in this cohort. RI and acute HF were the most frequent diagnoses, each representing nearly 30% of all ED visits, followed by COPD decompensations, which were half as common. PE and asthma decompensations were rarer. This distribution aligns with previous publications focused on individual diseases.³,¹² Notably, 23% of patients were categorized under ‘all other discharge diagnoses.’ Within this group,

one in four patients had evolving cancer, a subgroup that likely includes surgical and abdominal diseases often associated with dyspnoea.

The baseline characteristics of patients presenting with dyspnoea underscore the difficulty in diagnosing based on clinical phenotype, including past or concurrent diseases. Except for younger asthma patients with fewer comorbidities, other patients typically were around 70 years old with multiple cardiovascular risk factors and comorbidities such as stroke, arteritis, atrial fibrillation, cancer, chronic heart failure,
<figure><img src="image_10.png" /></figure>

<figure><img src="image_11.png" /><figcaption>**Figure 2** Risk of in-hospital mortality and post-discharge mortality according to dyspnoea aetiology (A) and hospitalization unit of care (B). COPD, Chronic obstructive pulmonary disease</figcaption></figure>

and COPD. Neither laboratory nor physical examination findings at admission distinctly pointed to a specific diagnosis. Notably, all subgroups had an average BNP level over 100 pg/mL, exceeding the threshold for ruling out heart failure as per guidelines.¹³ Similarly, the average CRP was above the threshold for inflammation in most groups, and no clinical parameters were uniquely indicative of any single disease. The atypical presentations in elderly patients complicate diagnosis, often leading to delayed treatment, extended ED stays, and increased short-term mortality.¹⁴ Therefore, more diagnostic tests are typically needed in the elderly to confirm a diagnosis compared with younger patients.¹⁵

## Admission severity and in-hospital mortality

In-hospital mortality in our cohort (overall 12%) was higher compared with previously published cohorts with AHF (5%),¹⁶ COPD exacerbation (3%),¹⁷ or RI (10%).¹⁸ This reflects the specific severity of patients hospitalized following ED visits for dyspnoea. Dyspnoea as an admission symptom represents a more severe manifestation of underlying diseases like AHF, COPD, and RI, compared with other symptoms like peripheral oedema, cough, or fever. The in-hospital mortality rate was mainly driven by AHF, RI, COPD decompensations, and non-cardiorespiratory causes. Interestingly, in-hospital mortality increased with age across all aetiologies, except for heart failure, which often shows a U-shaped mortality curve.¹⁹

## Long-term prognosis

Regardless of the underlying disease, 5-year mortality exceeded 25% in our study, with rates surpassing 60% for AHF, RI, and COPD. Both HF and COPD are characterized by progressive clinical deterioration and acute decompensation episodes, increasing the mortality rate during initial hospitalization and the months following, despite clinical improvement. Post-discharge is often a 'vulnerable phase'.²⁰ Surprisingly, despite being considered as an acute condition, RI mirrored HF's risk profile, with a 40% mortality rate within a year and 50% at 2 years post-discharge. For comparison, 5-year mortality rates are ~40% for colon cancer, 15% for breast cancer, and < 30% for prostate cancer.²¹ Similarly, 3-year mortality stands at 35% following acute coronary syndrome in patients over 65,²² and 5-year mortality is 50% after a stroke.²³ Therefore, a hospitalization for dyspnoea, particularly following an ED admission, should be seen as a significant indicator of high long-term mortality risk. Considering these findings, systematic post-discharge follow-up, including specialist consultation, should be recommended to optimize management of the underlying cardiorespiratory disease.

## Mortality according to hospitalization units

Patients hospitalized in specialized wards (as opposed to general units) exhibited significantly lower in-hospital mortality. Several factors might
A

<figure><img src="image_12.png" /></figure>

B

<figure><img src="image_13.png" /><figcaption>**Figure 3** Kaplan Meier curves in patients alive at discharge for all-cause mortality according to dyspnoea aetiology (A) and dyspnoea aetiology and age subgroups (B). COPD, Chronic obstructive pulmonary disease</figcaption></figure>

explain this difference in prognosis. Firstly, the characteristics of pa-
tients admitted to specialized care may differ. It is noteworthy that
these prognostic disparities consider variables like age and comorbid-
ities, typically assessed when deciding where the patients will be hospi-
talized. Another hypothesis is that patient management varies by ward

type, potentially influencing outcomes. Management in specialized units
is often more protocolized and aggressive. Moreover, early initiation of
effective treatments for cardiopulmonary aetiologies of dyspnoea,
such as diuretics or vasodilators for acute HF,¹³,²⁴ bronchodilators
for asthma and COPD decompensations,²⁵,²⁶ antibiotics for RI,²⁷ and
anticoagulation for PE,²⁸,²⁹ is crucial. The particularly noticeable outcome difference in AHF supports this, considering the complexities in managing AHF, like achieving decongestion and implementing HF treatment during hospitalization. Remarkably, only a quarter of AHF patients in our study were hospitalized in cardiology wards, suggesting only a minority of patients benefited from the specialized care and the significantly reduced mortality risk. Interestingly, the benefit of hospitalization in specialized care units was identical for patients with a prior medical history and those without, suggesting that the observed advantage of specialized care was not solely attributable to better patient referral pathways or care co-ordination.

## New perspectives for clinical practice

The current study is the first to underscore the severe in-hospital and long-term prognosis of a wide range of dyspnoea cases necessitating hospitalization in a non-selected population. The mortality rates are notably higher compared with other medical records. Apart from asthma and PE, 5-year mortality surpassed 60%, exceeding rates in myocardial infarction³⁰ (18%), stroke³¹ (39%), and most cancers, including breast³² (5%), colon³³ (<40%), and prostate³⁴ (10%). This suggests the need for a paradigm shift, treating hospitalized dyspnoea as a serious condition requiring meticulous management during and after hospitalization. Timely and precise diagnoses are essential for initiating early therapeutic interventions, which play a critical role in enhancing outcomes. Such strategy has indeed been shown to effectively reduce morbimortality in other acute conditions such severe sepsis,³⁵ stroke³⁶ and acute coronary syndrome.³⁷

The markedly better outcomes associated with specialized unit hospitalizations versus general wards underscore the importance of appropriate unit selection after ED admission for dyspnoea. In cases like RI or AHF, where in-hospital mortality exceeds 15%, efficient triage is essential to direct high-risk patients to specialized care, potentially significantly improving in-hospital and long-term survival rates. Like the establishment of 'chest pain units', there should be a strategy to develop and assess 'dyspnoea units' in order to improve both management and prognosis.

## Limitations

This study has several limitations inherent to its design. As an observational study, causal relationships cannot be firmly established. First, as a single-center study, it is subject to selection bias, although the hospital's public mission and large patient volume may enhance the generalizability of the findings. Differences in healthcare systems or geographic contexts may, however, result in variations in care pathways and outcomes. Second, survival analyses were based solely on the primary discharge diagnosis, which may oversimplify cases with multiple dyspnoea causes. Third, the study focused exclusively on patients hospitalized after an ED visit, excluding ambulatory patients presenting with dyspnoea. Fourth, information on time to treatment initiation, detailed in-hospital management, or previous ED admissions was not available, which may have provided additional insights into the observed differences in outcomes between care units and patient subgroups. Fifth, rheumatologic and oncological causes of dyspnoea were included in the 'Other' category, as these diagnoses encompass a broad spectrum of conditions and severities that may interact with dyspnoea, and could not be easily isolated in the current dataset. Finally, despite comprehensive variable adjustment, factors such as admission priority, dyspnoea severity, and socioeconomic status were not included, leaving room for potential residual confounding.

## Conclusions

Hospitalizations following ED visits for dyspnoea were linked to a 12% in-hospital mortality rate. The 5-year mortality rate for patients

discharged alive exceeded 25% across all underlying diseases, soaring above 60% for RI, heart failure, and COPD cases. Admissions to specialized units were associated with better in-hospital survival across all conditions and improved long-term survival for both RI and AHF.

## Supplementary data

Supplementary data are available at *European Journal of Heart Failure* online.

## Declarations

### Disclosure of Interest

G.B. has received personal fees from Abbott, AstraZeneca, Boehringer-Ingelheim and Novartis, NovoNordisk, outside the submitted work. C.L. has no conflicts of interest related to the submitted work. E.B. has no conflicts of interest related to the submitted work. L.M. has received personal fees from AstraZeneca and Vifor, outside the submitted work. A.M. has received grants from Roche Diagnostics, Abbott Laboratories, 4TEEN4, and Windtree Therapeutics; honoraria for lectures from Roche Diagnostics, Bayer, and MSD; is a consultant for Corteria Pharmaceuticals, S-form Pharma, FIRE-1, Implicit, 4TEEN4, and Adrenomed; and is coinventor of a patent on combination therapy for patients having acute or persistent dyspnoea. K.D. has no conflicts of interest related to the submitted work. D.J. has no conflicts of interest related to the submitted work. A.B. has no conflicts of interest related to the submitted work. A.B. has no conflicts of interest related to the submitted work. G.G. has no conflicts of interest related to the submitted work. C.D. has no conflicts of interest related to the submitted work. T.W. has no conflicts of interest related to the submitted work. F.Z. has received personal fees from 89Bio, Abbott, Acceleron, Applied Therapeutics, Bayer, Betagenon, Boehringer, BMS, CVRx, Cambrian, Cardior, Cereno pharmaceutical, Cellprothera, CEVA, Inventiva, KBP, Merck, NovoNordisk, Owkin, Otsuka, Roche Diagnostics, Northsea, USA2, having stock options at G3Pharmaceutical and equities at Cereno, Cardiorenal, Eshmoun Clinical research and being the founder of Cardiovascular ClinicalTrialists outside the submitted work. T.C. has no conflicts of interest related to the submitted work. N.G. has received personal fees from AstraZeneca, Bayer, Boehringer, Novartis and Vifor outside the submitted work.

### Data Availability

The data supporting the findings of this study are available from the corresponding author upon reasonable request.

### Funding

Nicolas Girerd is supported by government funding managed by the National Research Agency under France 2030 via the ENACT AI Cluster (ANR-23-IACL-0004).

### Ethical Approval

Ethical approval was not required.

### Pre-registered Clinical Trial Number

None supplied.

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