Long-term Prognosis in COPD Exacerbation: Role of Biomarkers, Clinical Variables and Exacerbation Type

Global mortality and readmission rates following COPD exacerbation-related hospitalisation: a meta-analysis of 65 945 individual patients

Background

Exacerbations of COPD (ECOPD) have a major impact on patients and healthcare systems across the world. Precise estimates of the global burden of ECOPD on mortality and hospital readmission are needed to inform policy makers and aid preventive strategies to mitigate this burden. The aims of the present study were to explore global in-hospital mortality, post-discharge mortality and hospital readmission rates after ECOPD-related hospitalisation using an individual patient data meta-analysis (IPDMA) design.

Methods

A systematic review was performed identifying studies that reported in-hospital mortality, post-discharge mortality and hospital readmission rates following ECOPD-related hospitalisation. Data analyses were conducted using a one-stage random-effects meta-analysis model. This study was conducted and reported in accordance with the PRISMA-IPD statement.

Results

Data of 65 945 individual patients with COPD were analysed. The pooled in-hospital mortality rate was 6.2%, pooled 30-, 90- and 365-day post-discharge mortality rates were 1.8%, 5.5% and 10.9%, respectively, and pooled 30-, 90- and 365-day hospital readmission rates were 7.1%, 12.6% and 32.1%, respectively, with noticeable variability between studies and countries. Strongest predictors of mortality and hospital readmission included noninvasive mechanical ventilation and a history of two or more ECOPD-related hospitalisations <12 months prior to the index event.

Conclusions

This IPDMA stresses the poor outcomes and high heterogeneity of ECOPD-related hospitalisation across the world. Whilst global standardisation of the management and follow-up of ECOPD-related hospitalisation should be at the heart of future implementation research, policy makers should focus on reimbursing evidence-based therapies that decrease (recurrent) ECOPD.

Novel Applications of Biomarkers in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is an important health problem and an increasing cause of morbidity and mortality worldwide. Currently, COPD is considered a multisystem disease. Although it primarily affects the lungs, structural and functional changes occur in other organs due to systemic inflammation. It is stated that in patients with COPD, airway and systemic inflammatory markers are increased and that these markers are high are associated with a faster decline in lung functions. In recent years, numerous articles have been published on the discovery and evaluation of biomarkers in COPD. Many markers have also been studied to accurately assess COPD exacerbations and provide effective treatment. However, based on the evidence from published studies, a single molecule has not been adequately validated for broad clinical use.

Predicting Mortality in COPD with Validated and Sensitive Biomarkers; Fibrinogen and Mid-Range-Proadrenomedullin (MR-proADM)

Although fibrinogen is a FDA qualified prognostic biomarker in COPD, it still lacks sufficient resolution to be clinically useful. Next to replication of findings in different cohorts also the combination with other validated biomarkers should be investigated. Therefore, the aim of this study was to confirm in a large well-defined population of COPD patients whether fibrinogen can predict mortality and whether a combination with the biomarker MR-proADM can increase prognostic accuracy. From the COMIC cohort study we included COPD patients with a blood sample obtained in stable state (n = 640) and/or at hospitalization for an acute exacerbation of COPD (n = 262). Risk of death during 3 years of follow up for the separate and combined biomarker models was analyzed with Cox regression. Furthermore, logistic regression models for death after one year were constructed. When both fibrinogen and MR-proADM were included in the survival model, a doubling in fibrinogen and MR-proADM levels gave a 2.2 (95% CI 1.3-3.7) and 2.1 (95% CI 1.5-3.0) fold increased risk of dying, respectively. The prediction model for death after 1 year improved significantly when MR-proADM was added to the model with fibrinogen (AUC increased from 0.78 to 0.83; p = 0.02). However, the combined model was not significantly more adequate than the model with solely MR-proADM (AUC 0.83 vs 0.82; p = 0.34). The study suggests that MR-proADM is more promising than fibrinogen in prediciting mortality. Adding fibrinogen to a model containing MR-proADM does not significantly increase the predictive capacity of the model.

2021 Guideline for the Management of COPD Exacerbations: Emergency Medicine Association of Turkey (EMAT) / Turkish Thoracic Society (TTS) Clinical Practice Guideline Task Force

Chronic obstructive pulmonary disease (COPD) is an important public health problem that manifests with exacerbations and causes serious mortality and morbidity in both developed and developing countries. COPD exacerbations usually present to emergency departments, where these patients are diagnosed and treated. Therefore, the Emergency Medicine Association of Turkey and the Turkish Thoracic Society jointly wanted to implement a guideline that evaluates the management of COPD exacerbations according to the current literature and provides evidence-based recommendations. In the management of COPD exacerbations, we aim to support the decision-making process of clinicians dealing with these patients in the emergency setting.

Pneumonia Is Associated with Increased Mortality in Hospitalized COPD Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) are at a heightened risk of pneumonia. Whether coexisting community-acquired pneumonia (CAP) can predict increased mortality in hospitalized COPD patients is still controversial.

OBJECTIVE

This systematic review and meta-analysis aims to assess the association between CAP and mortality and morbidity in COPD patients hospitalized for acute worsening of respiratory symptoms.

METHODS

In this review, cohort studies and case-control studies investigating the impact of CAP in hospitalized COPD patients were retrieved from 4 electronic databases from inception until December 2019. Methodological quality of included studies was assessed using Newcastle-Ottawa Quality Assessment Scale. The primary outcome was mortality. The secondary outcomes included length of hospital stay, need for mechanical ventilation, intensive care unit (ICU) admission, length of ICU stay, and readmission rate. The Mantel-Haenszel method and inverse variance method were used to calculate pooled relative risk (RR) and mean difference (MD), respectively.

RESULTS

A total of 18 studies were included. The presence of CAP was associated with higher mortality (RR = 1.85; 95% CI: 1.50-2.30; p < 0.00001), longer length of hospital stay (MD = 1.89; 95% CI: 1.19-2.59; p < 0.00001), more need for mechanical ventilation (RR = 1.48; 95% CI: 1.32-1.67; p < 0.00001), and more ICU admissions (RR = 1.58; 95% CI: 1.24-2.03; p = 0.0002) in hospitalized COPD patients. CAP was not associated with longer ICU stay (MD = 5.2; 95% CI: -2.35 to 12.74; p = 0.18) or higher readmission rate (RR = 1.02; 95% CI: 0.96-1.09; p = 0.47).

CONCLUSION

Coexisting CAP may be associated with increased mortality and morbidity in hospitalized COPD patients, so radiological confirmation of CAP should be required and more attention should be paid to these patients.

Does mid-regional pro-adrenomedullin (MR-proADM) improve the sequential organ failure assessment-score (SOFA score) for mortality-prediction in patients with acute infections? Results of a prospective observational study

OBJECTIVES

Risk stratification in patients with infection is usually based on the Sequential Organ Failure Assessment-Score (SOFA score). Our aim was to investigate whether the vasoactive peptide mid-regional pro-adrenomedullin (MR-proADM) improves the predictive value of the SOFA score for 30-day mortality in patients with acute infection presenting to the emergency department (ED).

METHODS

This secondary analysis of the prospective observational TRIAGE study included 657 patients with infection. The SOFA score, MR-proADM, and traditional inflammation markers were all measured at time of admission. Associations of admission parameters and 30-day mortality were investigated by measures of logistic regression, discrimination analyses, net reclassification index (NRI), and integrated discrimination index (IDI).

RESULTS

MR-proADM values were higher in non-survivors compared with survivors (4.5±3.5 nmol/L vs. 1.7 ± 1.8 nmol/L) with an adjusted odds ratio of 26.6 (95% CI 3.92 to 180.61, p=0.001) per 1 nmol/L increase in admission MR-proADM levels and an area under the receiver operator curve (AUC) of 0.86. While the SOFA score alone revealed an AUC of 0.81, adding MR-proADM further improved discrimination (AUC 0.87) and classification within predefined risk categories (NRI 0.075, p-value <0.05). An admission MR-proADM threshold of 1.75 nmol/L provided the best prognostic accuracy for 30-day mortality; with a sensitivity of 81% and a specificity of 75%, and a negative predictive value of 98%.

CONCLUSIONS

MR-proADM improved the mortality risk stratification in patients with infection presenting to the ED beyond SOFA score alone and may further improve initial therapeutic site-of-care decisions.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01768494. Registered January 15, 2013.

The vasoactive peptide MR-pro-adrenomedullin in COVID-19 patients: an observational study

OBJECTIVES

Midregional pro-adrenomedullin (MR-proADM) is a vasoactive peptide with key roles in reducing vascular hyperpermeability and thereby improving endothelial stability during infection. While MR-proADM is useful for risk stratification in patients with sepsis, clinical data about prediction accuracy in patients with severe acute respiratory syndrome coronavirus 2 disease (COVID-19) is currently missing.

METHODS

We included consecutively adult patients hospitalized for confirmed COVID-19 at a tertiary care center in Switzerland between February and April 2020. We investigated the association of MR-proADM levels with in-hospital mortality in logistic regression and discrimination analyses.

RESULTS

Of 89 included COVID-19 patients, 19% (n=17) died while in the hospital. Median admission MR-proADM levels (nmol/L) were increased almost 1.5-fold increased in non-survivors compared to survivors (1.3 [interquartile range IQR 1.1-2.3]) vs. 0.8 [IQR 0.7-1.1]) and showed good discrimination (area under the curve 0.78). An increase of 1 nmol/L of admission MR-proADM was independently associated with a more than fivefold increase in in-hospital mortality (adjusted odds ratio of 5.5, 95% confidence interval 1.4-21.4, p=0.015). An admission MR-proADM threshold of 0.93 nmol/L showed the best prognostic accuracy for in-hospital mortality with a sensitivity of 93%, a specificity of 60% and a negative predictive value of 97%. Kinetics of follow-up MR-proADM provided further prognostic information for in-hospital treatment.

CONCLUSIONS

Increased levels of MR-proADM on admission and during hospital stay were independently associated with in-hospital mortality and may allow a better risk stratification, and particularly rule-out of fatal outcome, in COVID-19 patients.

MR-proADM and MR-proANP levels in patients with acute pulmonary embolism

BACKGROUND

The aim of this study was to determine levels of Mid-regional Pro-adrenomedullin (MR-proADM) and Mid-regional Pro-atrial Natriuretic Peptide (MR-proANP) in patients with acute pulmonary embolism (PE), the relationship between these parameters and the risk classification in addition to determining the relationship between 1and 3month mortality.

METHODS

82 PE patients and 50 healthy control subjects were included in the study. Blood samples for Mr-proANP and Mr-proADM were obtained from the subjects prior to the treatment. Risk stratification was determined according to sPESI (Simplified Pulmonary Embolism Severity Index). Following these initial measurements, cases with PE were assessed in terms of all causative and PE related mortalities.

RESULTS

The mean serum Mr-proANP and Mr-proADM levels in acute PE patients were found to be statistically higher compared to the control group (p < 0.001, p < 0.01; respectively) and statistically significantly higher in high-risk patients than low-risk patients (p < 0.01, p < 0.05; respectively). No statistical difference was determined in high-risk patients in case of sPESI compared to low-risk patients while hospital mortality rates were higher. It was determined that the hospital mortality rate in cases with Mr-proANP ≥ 123.30 pmol/L and the total 3-month mortality rate in cases with Mr-proADM ≥ 152.2 pg/mL showed a statistically significant increase.

CONCLUSIONS

This study showed that Mr-proANP and MRproADM may be an important biochemical marker for determining high-risk cases and predicting the mortality in PE patients and we believe that these results should be supported by further and extensive studies.

Procalcitonin for Antibiotic Prescription in Chronic Obstructive Pulmonary Disease Exacerbations: Systematic Review, Meta-Analysis, and Clinical Perspective

The 2020 Global Initiative for Obstructive Lung Disease report indicates that the blood biomarker procalcitonin (PCT) may assist in decision-making regarding the initiation of antibiotics for chronic obstructive pulmonary disease (COPD) exacerbations. PCT is an acute-phase reactant that increases in response to inflammation and infection, and has been studied in various bacterial infections for initiation and de-escalation of antibacterials. The purpose of this systematic review and meta-analysis was to evaluate the strength of the data on the use of PCT to guide antibiotic prescription in COPD exacerbations. Among the randomized clinical trials included in our meta-analysis, almost all of which were conducted exclusively in the hospital setting. PCT was found to decrease overall antibiotic exposure in COPD exacerbations by 2.01 days (p = 0.04), while no apparent effects were found on clinical outcomes (length of hospital stay, p = 0.88; treatment failure p = 0.51; all-cause mortality p = 0.28). However, the majority of blood PCT levels in COPD exacerbations were below the manufacturer-recommended cutoff for antibiotics, and the use of this marker was associated with worse outcomes in the intensive care setting. Further, based on additional sensitivity analysis excluding studies with high risk of bias or with converted outcome value, the effect of PCT on antibiotic duration in RCTs was no longer significant (MD = -1.88 days, 95% CI [-3.95, 0.19] days, p = 0.08, and MD = -1.72 days, 95% CI [-4.28, 0.83] days, p = 0.19, respectively). Our review and analysis does not support the use of PCT to guide antibiotic prescription in COPD exacerbations.

Animal Models Reflecting Chronic Obstructive Pulmonary Disease and Related Respiratory Disorders: Translating Pre-Clinical Data into Clinical Relevance

Chronic obstructive pulmonary disease (COPD) affects the lives of an ever-growing number of people worldwide. The lack of understanding surrounding the pathophysiology of the disease and its progression has led to COPD becoming the third leading cause of death worldwide. COPD is incurable, with current treatments only addressing associated symptoms and sometimes slowing its progression, thus highlighting the need to develop novel treatments. However, this has been limited by the lack of experimental standardization within the respiratory disease research area. A lack of coherent animal models that accurately represent all aspects of COPD clinical presentation makes the translation of promising in vitrodata to human clinical trials exceptionally challenging. Here, we review current knowledge within the COPD research field, with a focus on current COPD animal models. Moreover, we include a set of advantages and disadvantages for the selection of pre-clinical models for the identification of novel COPD treatments.

Plasma levels of C-reactive protein, matrix metalloproteinase-7 and lipopolysaccharide-binding protein distinguish active pulmonary or extrapulmonary tuberculosis from uninfected controls in children

The immune profile associated with distinct clinical forms of tuberculosis (TB) has been extensively described for adult populations. Nevertheless, studies describing immune determinants of pulmonary or extrapulmonary TB (PTB or EPTB, respectively) in children are scarce. Here, we retrospectively assessed plasma levels of several mediators of inflammation in age and sex-matched children from South India presenting with PTB (n = 14) or EPTB (n = 22) as well as uninfected healthy controls (n = 19) to identify biomarkers that could accurately distinguish different TB clinical forms. Furthermore, we performed exploratory analyses testing the influence of sex on the systemic inflammatory profile. The analyses identified a biosignature of 10 biomarkers capable of distinguishing the three clinical groups simultaneously. Machine-learning decision trees indicated that C-reactive protein (CRP), matrix metalloproteinase (MMP)-7 and lipopolysaccharide-binding protein (LBP) were the markers that, when combined, displayed the highest accuracy in identifying the clinical groups. Additional exploratory analyses suggested that the disease signatures were highly influenced by sex. Therefore, sex differentially impacted status of systemic inflammation, immune activation and tissue remodeling in children with distinct clinical forms of TB. Regardless of such nuances related to biological sex, MMP-7, CRP and LBP were strong discriminators of active TB and thus could be considered as biomarkers useful in discrimination different TB clinical forms. These observations have implications on our understanding of the immunopathology of both clinical forms of TB in pediatric patients. If validated by other studies in the future, the combination of identified biomarkers may help development of point-of-care diagnostic or prognostic tools.

Extrafine triple therapy delays COPD clinically important deterioration vs ICS/LABA, LAMA, or LABA/LAMA

Background

Current pharmacological therapies for COPD improve quality of life and symptoms and reduce exacerbations. Given the progressive nature of COPD, it is arguably more important to understand whether the available therapies are able to delay clinical deterioration; the concept of “clinically important deterioration” (CID) has therefore been developed. We evaluated the efficacy of the single-inhaler triple combination beclometasone dipropionate, formoterol fumarate, and glycopyrronium (BDP/FF/G), using data from three large 1-year studies.

Methods

The studies compared BDP/FF/G to BDP/FF (TRILOGY), tiotropium (TRINITY), and indacaterol/glycopyrronium (IND/GLY; TRIBUTE). All studies recruited patients with symptomatic COPD, FEV₁ <50%, and an exacerbation history. We measured the time to first CID and to sustained CID, an endpoint combining FEV₁, St George’s Respiratory Questionnaire (SGRQ), moderate-to-severe exacerbations, and death. The time to first CID was based on the first occurrence of any of the following: a decrease of ≥100 mL from baseline in FEV₁, an increase of ≥4 units from baseline in SGRQ total score, the occurrence of a moderate/severe COPD exacerbation, or death. The time to sustained CID was defined as: a CID in FEV₁ and/or SGRQ total score maintained at all subsequent visits, an exacerbation, or death.

Results

Extrafine BDP/FF/G significantly extended the time to first CID vs BDP/FF (HR 0.61, P<0.001), tiotropium (0.72, P<0.001), and IND/GLY (0.82, P<0.001), and significantly extended the time to sustained CID vs BDP/FF (HR 0.64, P<0.001) and tiotropium (0.80, P<0.001), with a numerical extension vs IND/GLY.

Conclusion

In patients with symptomatic COPD, FEV₁ <50%, and an exacerbation history, extrafine BDP/FF/G delayed disease deterioration compared with BDP/FF, tiotropium, and IND/GLY.

Trial registration

The studies are registered in ClinicalTrials.gov: TRILOGY, NCT01917331; TRINITY, NCT01911364; TRIBUTE, NCT02579850.

Biomarkers and clinical outcomes in COPD: a systematic review and meta-analysis

Background

Conventional measures to evaluate COPD may fail to capture systemic problems, particularly musculoskeletal weakness and cardiovascular disease. Identifying these manifestations and assessing their association with clinical outcomes (ie, mortality, exacerbation and COPD hospital admission) is of increasing clinical importance.

Objective

To assess associations between 6 min walk distance (6MWD), heart rate, fibrinogen, C reactive protein (CRP), white cell count (WCC), interleukins 6 and 8 (IL-6 and IL-8), tumour necrosis factor-alpha, quadriceps maximum voluntary contraction, sniff nasal inspiratory pressure, short physical performance battery, pulse wave velocity, carotid intima-media thickness and augmentation index and clinical outcomes in patients with stable COPD.

Methods

We systematically searched electronic databases (August 2018) and identified 61 studies, which were synthesised, including meta-analyses to estimate pooled HRs, following Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results

Shorter 6MWD and elevated heart rate, fibrinogen, CRP and WCC were associated with higher risk of mortality. Pooled HRs were 0.80 (95% CI 0.73 to 0.89) per 50 m longer 6MWD, 1.10 (95% CI 1.02 to 1.18) per 10 bpm higher heart rate, 3.13 (95% CI 2.14 to 4.57) per twofold increase in fibrinogen, 1.17 (95% CI 1.06 to 1.28) per twofold increase in CRP and 2.07 (95% CI 1.29 to 3.31) per twofold increase in WCC. Shorter 6MWD and elevated fibrinogen and CRP were associated with exacerbation, and shorter 6MWD, higher heart rate, CRP and IL-6 were associated with hospitalisation. Few studies examined associations with musculoskeletal measures.

Conclusion

Findings suggest 6MWD, heart rate, CRP, fibrinogen and WCC are associated with clinical outcomes in patients with stable COPD. Use of musculoskeletal measures to assess outcomes in patients with COPD requires further investigation.

Trial registration number

CRD42016052075.

Relative lymphocyte count as an indicator of 3-year mortality in elderly people with severe COPD

BACKGROUND

Prognostic stratification of elderly patients with chronic obstructive pulmonary disease (COPD) is difficult due to the wide inter-individual variability in the course of the disease. No marker can exactly stratify the evolution and natural history of COPD patients. Studies have shown that leukocyte count is associated with increased risk of mortality in COPD patients. The aim of this study was to evaluate the possible role of relative lymphocyte count as a risk marker for mortality in elderly patients with COPD.

METHODS AND RESULTS

This is a3-year prospective study. A total of 218patients, mean age 75.2±7 years, with moderate to severe COPD and free from conditions affecting lymphocyte count were enrolled. The population was divided into two groups according to the relative lymphocyte count, with a cut-off of 20%. Eighty-five patients (39%) had a relative lymphocyte count ≤20%. Three-year mortality rates from any cause in patients with relative lymphocyte count ≤ or > 20% were 68 and 51%, respectively (p = 0.0012). Survival curve analysis showed higher mortality in patients with relative lymphocyte count ≤20% (p = 0.0005). After adjustment for age and sex, the hazard ratio for mortality risk according to lymphocyte count was 1.79 (95% confidence interval [CI]: 1.26-2.57, p = 0.0013), even in the analysis limited to the 171 patients without congestive heart failure (1.63; 95% CI: 1.03-2.58, p = 0.038).

CONCLUSIONS

Low relative lymphocyte count was associated with higher mortality in elderly patients with severe COPD.

The Use of Serum Procalcitonin as a Diagnostic and Prognostic Biomarker in Chronic Obstructive Pulmonary Disease Exacerbations: A Literature Review Update

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a major complication in COPD patients which can be triggered by bacterial or viral infections, environmental pollutants and other causes. Procalcitonin (PCT), a peptide that markedly increases in cases of bacterial infection, has been extensively investigated as a biomarker in the diagnosis, prognosis and treatment in patients with AECOPD. A number of studies published in the last decade, tried to investigate whether PCT levels can differentiate between bacterial and other causes of exacerbations, if they can be used as a guide for optimal antibiotic therapy and if they can be a tool in the assessment of the severity and the need for further interventions in the management of those patients. This review aims to gather, summarize and critically present all the available data to date.

Evaluation of platelet lymphocyte ratio and 90-day mortality in patients with acute exacerbation of chronic obstructive pulmonary disease

BACKGROUND

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) have high mortality and health care costs. The platelet to lymphocyte ratio (PLR) is a marker of inflammation and has been reported to be elevated in patients with AECOPD compared to stable state. In this study, we sought to evaluate the association of the PLR in patients with AECOPD with 90-day mortality.

METHODS

We conducted a retrospective cohort study of patients admitted to our institution with a primary diagnosis of AECOPD between January 2014 and July 2014. Blood test results on admission were recorded. The primary outcomes were 90-day mortality.

RESULTS

One hundred and eighty-one AECOPD patients were considered for the study. Death had occurred in 16 (9%) patients within 90 days of hospital discharge. Univariable analysis identified age, haemoglobin, neutrophil count, and urea level, neutrophil lymphocyte ratio (NLR) and PLR as being associated with increased 90-day mortality. Multivariable logistic regression analysis variables demonstrated that only PLR (P=0.03) was significantly associated with death at 90 days. Receiver operator characteristic analysis identified PLR ≥235 had a sensitivity of 63% and specificity of 74% in predicting 90-day mortality. PLR was ≥235 was also associated with worse survival (days) [mean ± standard deviation (SD): PLR ≥235 vs. PLR <235: 512±358 vs. 626±346, P=0.004].

CONCLUSIONS

A PLR ≥235 was significantly associated with 90-day mortality, which may provide prognostic guidance to clinicians.

Activation of the Serotonin Pathway is Associated with Poor Outcome in COPD Exacerbation: Results of a Long-Term Cohort Study

BACKGROUND/INTRODUCTION

Indoleamine 2,3-dioxygenase (IDO) metabolizes tryptophan to kynurenine. An increase of its activity is associated with severity in patients with pneumonia. In chronic obstructive pulmonary disease (COPD) patients, an elevation of serotonin has been reported. Experimental models showed that cigarette smoke inhibits monoamine oxidase (MAO) leading to higher levels of serotonin. We investigated the prognostic ability of tryptophan, serotonin, kynurenine, IDO, and tryptophan hydroxylase (TPH) to predict short- and long-term outcomes in patients with a COPD exacerbation.

METHODS

We measured tryptophan, serotonin, and kynurenine on admission plasma samples in patients with a COPD exacerbation from a previous trial by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). IDO and TPH were calculated as ratios of kynurenine over tryptophan, and serotonin over tryptophan, respectively. We studied their association with parameters measured in clinical routine at emergency department admission representing inflammation (C-reactive protein [CRP]), infection (procalcitonin [PCT]), oxygenation (SpO₂), as well as patients' clinical outcome, confirmed by structured phone interviews.

RESULTS

Mortality in the 149 included patients was 53.7% within six years of follow-up. While IDO activity showed strong positive correlations, tryptophan was negatively correlated with CRP and PCT. For 30-day adverse outcome defined as death and/or intensive care unit (ICU) admission, a multivariate regression analysis adjusted for age and comorbidities found strong associations for IDO activity (adjusted odds ratios of 31.4 (95%CI 1.1-857), p = 0.041) and TPH (adjusted odds ratios 27.0 (95%CI 2.2-327), p = 0.010). TPH also showed a significant association with mortality at 18 months, (hazard ratio 2.61 (95%CI 1.2-5.8), p = 0.020).

CONCLUSION

In hospitalized patients with a COPD exacerbation, higher IDO and TPH activities independently predicted adverse short-term outcomes and TPH levels were also predictive of 18-month mortality. Whether therapeutic modulation of the serotonin pathway has positive effects on outcome needs further investigation.

Time-dependent association of glucocorticoids with adverse outcome in community-acquired pneumonia: a 6-year prospective cohort study

Background

The hypothalamic-pituitary-adrenal stress axis plays a crucial role in community-acquired pneumonia (CAP), with high cortisol being associated with disease severity and corticosteroid treatment resulting in earlier time to recovery. Our aim in the present study was to compare different glucocorticoid hormones, including cortisol, 11-deoxycortisol, cortisone, and corticosterone, regarding their association with short- and long-term adverse outcomes in a well-defined CAP cohort.

Methods

We prospectively followed 285 patients with CAP from a previous Swiss multicenter trial for a median of 6.1 years and measured different admission glucocorticoid serum levels by liquid chromatography coupled with tandem mass spectrometry. We used adjusted Cox regression models to investigate associations between admission hormone levels and all-cause mortality at different time points.

Results

Mortality was 5.3% after 30 days and increased to 47.3% after 6 years. High admission cortisol was associated with adverse outcome after 30 days (adjusted OR 3.85, 95% CI 1.10–13.49, p = 0.035). In the long term (i.e.,), however, high admission cortisol was associated with better survival (adjusted HR after 3 years 0.53, 95% CI 0.32–0.89, p = 0.017; adjusted HR after 6 years 0.57, 95% CI 0.36–0.90, p = 0.015). Compared with 11-deoxycortisol, cortisone, and corticosterone, cortisol showed the highest association with mortality.

Conclusions

Among different glucocorticoid hormones, cortisol showed the highest association with mortality in CAP. Whereas a more pronounced glucocorticoid stress response on hospital admission was associated with higher short-term adverse outcome, long-term outcome was favorable in these patients. These data should support the correct interpretation of glucocorticoid blood data.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1656-7) contains supplementary material, which is available to authorized users.

The TRIAGE-ProADM Score for an Early Risk Stratification of Medical Patients in the Emergency Department - Development Based on a Multi-National, Prospective, Observational Study

INTRODUCTION

The inflammatory biomarker pro-adrenomedullin (ProADM) provides additional prognostic information for the risk stratification of general medical emergency department (ED) patients. The aim of this analysis was to develop a triage algorithm for improved prognostication and later use in an interventional trial.

METHODS

We used data from the multi-national, prospective, observational TRIAGE trial including consecutive medical ED patients from Switzerland, France and the United States. We investigated triage effects when adding ProADM at two established cut-offs to a five-level ED triage score with respect to adverse clinical outcome.

RESULTS

Mortality in the 6586 ED patients showed a step-wise, 25-fold increase from 0.6% to 4.5% and 15.4%, respectively, at the two ProADM cut-offs (≤0.75nmol/L, >0.75-1.5nmol/L, >1.5nmol/L, p ANOVA <0.0001). Risk stratification by combining ProADM within cut-off groups and the triage score resulted in the identification of 1662 patients (25.2% of the population) at a very low risk of mortality (0.3%, n = 5) and 425 patients (6.5% of the population) at very high risk of mortality (19.3%, n = 82). Risk estimation by using ProADM and the triage score from a logistic regression model allowed for a more accurate risk estimation in the whole population with a classification of 3255 patients (49.4% of the population) in the low risk group (0.3% mortality, n = 9) and 1673 (25.4% of the population) in the high-risk group (15.1% mortality, n = 252).

CONCLUSIONS

Within this large international multicenter study, a combined triage score based on ProADM and established triage scores allowed a more accurate mortality risk discrimination. The TRIAGE-ProADM score improved identification of both patients at the highest risk of mortality who may benefit from early therapeutic interventions (rule in), and low risk patients where deferred treatment without negatively affecting outcome may be possible (rule out).

Prognostic utility of admission cell-free DNA levels in patients with chronic obstructive pulmonary disease exacerbations

Background

Chronic obstructive pulmonary disease exacerbations (COPDEs) are associated with increased morbidity and mortality. Cell-free DNA (cfDNA) is a novel biomarker associated with clinical outcomes in several disease states but has not been studied in COPD. The objectives of this study were to assess cfDNA levels during a COPDE, to evaluate the association of cfDNA with clinical parameters and to explore the prognostic implications of cfDNA levels on long-term survival.

Methods

This was an observational study that assessed cfDNA levels in patients admitted to hospital for a COPDE. Plasma cfDNA levels of COPDE patients were compared to those of matched stable COPD patients and healthy controls. Multivariable and Cox regression analyses were used to assess the association of cfDNA levels with blood gas parameters and long-term survival.

Results

A total of 62 patients (46 males, forced expiratory volume in 1 second [FEV₁] 38%±13%) were included. The median cfDNA levels on admission for COPDE patients was 1,634 ng/mL (interquartile range [IQR] 1,016–2,319) compared to 781 ng/mL (IQR 523–855) for stable COPD patients, matched for age and disease severity, and 352 ng/mL (IQR 209–636) for healthy controls (P<0.0001, for both comparisons). cfDNA was correlated with partial arterial pressure of carbon dioxide (PaCO₂, r=0.35) and pH (r=−0.35), P=0.01 for both comparisons. In a multivariable analysis, PaCO₂ was the only independent predictor of cfDNA. Using a cfDNA level of 1,924 ng/mL (threshold for abnormal PaCO₂), those with high levels had a trend for increased 5-year mortality risk adjusted for age, sex and FEV₁% (hazard ratio 1.92, 95% confidence interval 0.93–3.95, P=0.08).

Conclusion

Plasma cfDNA might offer a novel technique to identify COPD patients at increased risk of poor outcomes, but the prognostic utility of this measurement requires further study.

Stable State Proadrenomedullin Level in COPD Patients: A Validation Study

In patients with stable COPD, proadrenomedullin (MR-proADM) has been shown to be a good predictor for mortality. This study aims to provide an external validation of earlier observed cut-off values used by Zuur-Telgen et al. and Stolz.et al. in COPD patients in stable state and at hospitalization for an acute exacerbation of COPD (AECOPD). From the COMIC cohort study we included 545 COPD patients with a blood sample obtained in stable state (n = 490) and/or at hospitalization for an AECOPD (n = 101). Time to death was compared between patients with MR-proADM cut-off scores 0.71 and 0.75 nmol/L for stable state or 0.79 and 0.84 nmol/l for AECOPD. The predictive value of MR-proADM for survival was represented by the C statistic. Risk ratios were corrected for sex, age, BMI, presence of heart failure, and GOLD stage. Patients above the cut-off of 0.75 nmol/l had a 2-fold higher risk of dying than patient below this cut-off (95% CI: 1.20-3.41). The cut-off of 0.71 nmol/l showed only a borderline significantly higher risk of 1.67 (95% CI: 0.98-2.85). The corrected odds ratios for one-year mortality were 3.15 (95% CI 1.15-8.64) and 3.70 (95% CI 1.18-11.6) in patients with MR-proADM levels above versus below the cut-off of respectively 0.75 and 0.71 nmol/l measured in stable state. MR-proADM levels in samples at hospitalization for an AECOPD were not predictive for mortality in this validation cohort. MR-proADM in stable state is a powerful predictor for mortality.

Diagnosing sepsis - The role of laboratory medicine

Sepsis is the host response to microbial pathogens resulting in significant morbidity and mortality. An accurate and timely diagnosis of sepsis allows prompt and appropriate treatment. This review discusses laboratory testing for sepsis because differentiating systemic inflammation from infection is challenging. Procalcitonin (PCT) is currently an FDA approved test to aid in the diagnosis of sepsis but with questionable efficacy. However, studies support the use of PCT for antibiotic de-escalation. Serial lactate measurements have been recommended for monitoring treatment efficacy as part of sepsis bundles. The 2016 sepsis consensus definitions include lactate concentrations >2mmol/L (>18mg/dL) as part of the definition of septic shock. Also included in the 2016 definitions are measuring bilirubin and creatinine to determine progression of organ failure indicating worse prognosis. Hematologic parameters, including a simple white blood cell count and differential, are frequently part of the initial sepsis diagnostic protocols. Several new biomarkers have been proposed to diagnose sepsis or to predict mortality, but they currently lack sufficient sensitivity and specificity to be considered as stand-alone testing. If sepsis is suspected, new technologies and microbiologic assays allow rapid and specific identification of pathogens. In 2016 there is no single laboratory test that accurately diagnoses sepsis.

Implications of the inflammatory response for the identification of biomarkers of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by both local and systemic inflammation. Because inflammation plays a critical role in the development, course and severity of COPD, inflammatory markers have the potential to improve the current diagnostic and prognostic approaches. Local inflammation in COPD is characterized by an infiltration of inflammatory cells, with an increased expression of cytokines, chemokines, enzymes, growth factors and adhesion molecules. Systemic low-grade inflammation is another common but nonspecific finding in COPD. Exacerbations of COPD are acute clinical events accompanied by an exaggerated inflammatory response. Future investigations in the field of COPD biomarkers should take into account different study designs and biochemical assays, disease course and duration, variations in symptom severity and timing of measurement.

Systematic review regarding metabolic profiling for improved pathophysiological understanding of disease and outcome prediction in respiratory infections

Metabolic profiling through targeted quantification of a predefined subset of metabolites, performed by mass spectrometric analytical techniques, allows detailed investigation of biological pathways and thus may provide information about the interaction of different organic systems, ultimately improving understanding of disease risk and prognosis in a variety of diseases. Early risk assessment, in turn, may improve patient management in regard to cite-of-care decisions and treatment modalities. Within this review, we focus on the potential of metabolic profiling to improve our pathophysiological understanding of disease and management of patients. We focus thereby on lower respiratory tract infections (LRTI) including community-acquired pneumonia (CAP) and chronic obstructive pulmonary disease (COPD), an important disease responsible for high mortality, morbidity and costs worldwide. Observational data from numerous clinical and experimental studies have provided convincing data linking metabolic blood biomarkers such as lactate, glucose or cortisol to patient outcomes. Also, identified through metabolomic studies, novel innovative metabolic markers such as steroid hormones, biogenic amines, members of the oxidative status, sphingo- and glycerophospholipids, and trimethylamine-N-oxide (TMAO) have shown promising results. Since many uncertainties remain in predicting mortality in these patients, further prospective and retrospective observational studies are needed to uncover metabolic pathways responsible for mortality associated with LRTI. Improved understanding of outcome-specific metabolite signatures in LRTIs may optimize patient management strategies, provide potential new targets for future individual therapy, and thereby improve patients' chances for survival.

Procalcitonin improves the Glasgow Prognostic Score for outcome prediction in emergency patients with cancer: a cohort study

The Glasgow Prognostic Score (GPS) is useful for predicting long-term mortality in cancer patients. Our aim was to validate the GPS in ED patients with different cancer-related urgency and investigate whether biomarkers would improve its accuracy. We followed consecutive medical patients presenting with a cancer-related medical urgency to a tertiary care hospital in Switzerland. Upon admission, we measured procalcitonin (PCT), white blood cell count, urea, 25-hydroxyvitamin D, corrected calcium, C-reactive protein, and albumin and calculated the GPS. Of 341 included patients (median age 68 years, 61% males), 81 (23.8%) died within 30 days after admission. The GPS showed moderate prognostic accuracy (AUC 0.67) for mortality. Among the different biomarkers, PCT provided the highest prognostic accuracy (odds ratio 1.6 (95% confidence interval 1.3 to 1.9), P < 0.001, AUC 0.69) and significantly improved the GPS to a combined AUC of 0.74 (P = 0.007). Considering all investigated biomarkers, the AUC increased to 0.76 (P < 0.001). The GPS performance was significantly improved by the addition of PCT and other biomarkers for risk stratification in ED cancer patients. The benefit of early risk stratification by the GPS in combination with biomarkers from different pathways should be investigated in further interventional trials.