Predicting mortality for patients with exacerbations of COPD and Asthma in the COPD and Asthma Outcome Study (CAOS)

Criteria for Enrollment of Patients With COPD in Palliative Care Trials: A Systematic Review

CONTEXT

Use of palliative care interventions in chronic obstructive pulmonary disease (COPD) has increased in recent years and inclusion criteria used to identify patients with COPD appropriate for palliative care vary widely. We evaluated the inclusion criteria to identify ways to improve enrollment opportunities for patients with COPD.

OBJECTIVES

To determine inclusion criteria used to select patients with COPD for palliative care trials.

METHODS

A systematic review was conducted to determine criteria used to select patients with COPD for palliative care randomized controlled trials. A narrative synthesis was conducted for all trials.

RESULTS

Inclusion criteria were highly heterogeneous. Most studies (n = 11, 79%) used a combination of criteria to identify patients with COPD. Commonly used criteria included hospitalization for an acute exacerbation of COPD (n = 8, 57%), home supplemental oxygen use (n = 8, 57%), and spirometry values confirming COPD (n = 6, 43%). Three studies (21.4%) used Modified Medical Research Council score and two studies (21%) used physician prognosis or a performance scale.

CONCLUSION

The most common criteria, a hospitalization for acute exacerbation of COPD or supplemental oxygen use at home, both have the benefit of selecting patients who have a higher symptom burden or higher healthcare utilization who might therefore benefit more from palliative care. By describing the landscape and variability of previously used inclusion criteria, this article serves as a resource for clinicians and researchers. Developing a consistent set of inclusion criteria in the future would help generate generalizable results that can be translated into clinical practice to improve the lives of patients with COPD.

PROSPERO REGISTRATION NUMBER

CRD42022306752.

Predictors of Length of Stay, Mortality and Rehospitalization in COPD Patients: A Retrospective Cohort Study

Chronic obstructive pulmonary disease (COPD) is a highly prevalent chronic lung disease that has a significant impact on individuals and healthcare systems worldwide. This study aimed to identify factors that predict the length of a hospital stay (LOHS), one-year mortality, and rehospitalization within 6 months in patients admitted for acute exacerbation of COPD (AECOPD). A retrospective cohort study was conducted using data from 170 patients admitted to a district general hospital in Switzerland between January 2019 and February 2020. Sociodemographic and health-related variables measured at admission were analyzed as potential predictors. Multivariable zero-truncated negative binomial and logistic regression analyses were performed to assess the risk factors for LOHS (primary endpoint), mortality, and rehospitalization. The results show that an indication for oxygen supplementation was the only significant predictor of LOHS. In the logistic regression analysis, older age, COPD severity stages GOLD III and IV, active cancer and arrhythmias were associated with higher mortality, whereas rehabilitation after discharge was associated with lower mortality. There were no significant associations regarding rehospitalization. This study identified routinely available predictors for LOHS and mortality, which may further advance our understanding of AECOPD and thereby improve patient management, discharge planning, and hospital costs. The protective effect of rehabilitation after hospitalization regarding lower mortality warrants further confirmation and may improve the comprehensive management of patients with AECOPD.

State of the Art of Machine Learning-Enabled Clinical Decision Support in Intensive Care Units: Literature Review

Background

Modern clinical care in intensive care units is full of rich data, and machine learning has great potential to support clinical decision-making. The development of intelligent machine learning–based clinical decision support systems is facing great opportunities and challenges. Clinical decision support systems may directly help clinicians accurately diagnose, predict outcomes, identify risk events, or decide treatments at the point of care.

Objective

We aimed to review the research and application of machine learning–enabled clinical decision support studies in intensive care units to help clinicians, researchers, developers, and policy makers better understand the advantages and limitations of machine learning–supported diagnosis, outcome prediction, risk event identification, and intensive care unit point-of-care recommendations.

Methods

We searched papers published in the PubMed database between January 1980 and October 2020. We defined selection criteria to identify papers that focused on machine learning–enabled clinical decision support studies in intensive care units and reviewed the following aspects: research topics, study cohorts, machine learning models, analysis variables, and evaluation metrics.

Results

A total of 643 papers were collected, and using our selection criteria, 97 studies were found. Studies were categorized into 4 topics—monitoring, detection, and diagnosis (13/97, 13.4%), early identification of clinical events (32/97, 33.0%), outcome prediction and prognosis assessment (46/97, 47.6%), and treatment decision (6/97, 6.2%). Of the 97 papers, 82 (84.5%) studies used data from adult patients, 9 (9.3%) studies used data from pediatric patients, and 6 (6.2%) studies used data from neonates. We found that 65 (67.0%) studies used data from a single center, and 32 (33.0%) studies used a multicenter data set; 88 (90.7%) studies used supervised learning, 3 (3.1%) studies used unsupervised learning, and 6 (6.2%) studies used reinforcement learning. Clinical variable categories, starting with the most frequently used, were demographic (n=74), laboratory values (n=59), vital signs (n=55), scores (n=48), ventilation parameters (n=43), comorbidities (n=27), medications (n=18), outcome (n=14), fluid balance (n=13), nonmedicine therapy (n=10), symptoms (n=7), and medical history (n=4). The most frequently adopted evaluation metrics for clinical data modeling studies included area under the receiver operating characteristic curve (n=61), sensitivity (n=51), specificity (n=41), accuracy (n=29), and positive predictive value (n=23).

Conclusions

Early identification of clinical and outcome prediction and prognosis assessment contributed to approximately 80% of studies included in this review. Using new algorithms to solve intensive care unit clinical problems by developing reinforcement learning, active learning, and time-series analysis methods for clinical decision support will be greater development prospects in the future.

The MAGENTA model for individual prediction of in-hospital mortality in chronic obstructive pulmonary disease with acute exacerbation in resource-limited countries: A development study

BACKGROUND

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a common undesirable event associated with significant morbidity and mortality. Several clinical prediction tools for predicting in-hospital mortality in patients with AECOPD have been developed in the past decades. However, some issues concerning the validity and availability of some predictors in the existing models may undermine their clinical applicability in resource-limited clinical settings.

METHODS

We developed a multivariable model for predicting in-hospitality from a retrospective cohort of patients admitted with AECOPD to one tertiary care center in Thailand from October 2015 to September 2017. Multivariable logistic regression with fractional polynomial algorithms and cluster variance correction was used for model derivation.

RESULTS

During the study period, 923 admissions from 600 patients with AECOPD were included. The in-hospital mortality rate was 1.68 per 100 admission-day. Eleven potential predictors from the univariable analysis were included in the multivariable logistic regression. The reduced model, named MAGENTA, incorporated seven final predictors: age, body temperature, mean arterial pressure, the requirement of endotracheal intubation, serum sodium, blood urea nitrogen, and serum albumin. The model discriminative ability based on the area under the receiver operating characteristic curve (AuROC) was excellent at 0.82 (95% confidence interval 0.77, 0.86), and the calibration was good.

CONCLUSION

The MAGENTA model consists of seven routinely available clinical predictors upon patient admissions. The model can be used as an assisting tool to aid clinicians in accurate risk stratification and making appropriate decisions to admit patients for intensive care.

DECAF score as a mortality predictor for acute exacerbation of chronic obstructive pulmonary disease: a systematic review and meta-analysis

OBJECTIVES

This study was conducted to assess the association between the Dyspnea, Eosinopenia, Consolidation, Acidemia and Atrial Fibrillation (DECAF) scores and the prognosis of patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD), to evaluate the specific predictive and prognostic value of DECAF scores and to explore the effectiveness of different cut-off values in risk stratification of patients with AECOPD.

DESIGN

Systematic review and meta-analysis.

PARTICIPANTS

Adult patients diagnosed with AECOPD (over 18 years of age).

PRIMARY AND SECONDARY OUTCOME MEASURES

Electronic databases, including the Cochrane Library, PubMed, the Embase and the WOS, and the reference lists in related articles were searched for studies published up to September 2019. The identified studies reported the prognostic value of DECAF scores in patients with AECOPD.

RESULTS

Seventeen studies involving 8329 participants were included in the study. Quantitative analysis demonstrated that elevated DECAF scores were associated with high mortality risk (weighted mean difference=1.87; 95% CI 1.19 to 2.56). In the accuracy analysis, DECAF scores showed good prognostic accuracy for both in-hospital and 30-day mortality (area under the receiver operating characteristic curve: 0.83 (0.79-0.86) and 0.79 (0.76-0.83), respectively). When the prognostic value was compared with that of other scoring systems, DECAF scores showed better prognostic accuracy and stable clinical values than the modified DECAF; COPD and Asthma Physiology Score; BUN, Altered mental status, Pulse and age >65; Confusion, Urea, Respiratory Rate, Blood pressure and age >65; or Acute Physiology and Chronic Health Evaluation II scores.

CONCLUSION

The DECAF score is an effective and feasible predictor for short-term mortality. As a specific and easily scored predictor for patients with AECOPD, DECAF score is superior to other prognostic scores. The DECAF score can correctly identify most patients with AECOPD as low risk, and with the increase of cut-off value, the risk stratification of DECAF score in high-risk population increases significantly.

Predictors of NIV Treatment in Patients with COPD Exacerbation Complicated by Respiratory Acidaemia

Non-invasive ventilation (NIV) treatment decisions are poorly understood for patients with COPD exacerbation complicated by acute hypercapnic respiratory failure and respiratory acidaemia (ECOPD-RA). We identified 420 NIV-eligible patients from the DECAF study cohorts admitted with an ECOPD-RA. Using bivariate and multivariate analyses, we examined which indices were associated with clinicians' decisions to start NIV, including whether the presence of pneumonia was a deterrent. Admitting hospital, admission from institutional care, partial pressure of oxygen, cerebrovascular disease, pH, systolic blood pressure and white cell count were all associated with the provision of NIV. Of these indices, only pH was also a predictor of inpatient death. Those not treated with NIV included those with milder acidaemia and higher (and sometimes excessive) oxygen levels, and a frailer population with higher Extended Medical Research Council Dyspnoea scores, presumably deemed not suitable for NIV. Pneumonia was not associated with NIV treatment; 34 of 111 (30.6%) NIV-untreated patients had pneumonia, whilst 107 of 309 (34.6%) NIV-treated patients had pneumonia (p = 0.483). In our study, one in four NIV-eligible patients were not treated with NIV. Clinicians' NIV treatment decisions are not based on those indices most strongly associated with mortality risk. One of the strongest predictors of whether a patient received a life-saving treatment is which hospital they attended. Further research is required to aid in the risk stratification of this patient group which may help standardise and improve care.

Mortality and its predictors among patients treated for acute exacerbations of chronic obstructive respiratory diseases in Jimma Medical Center; Jimma, Ethiopia: Prospective observational study

Background

Chronic obstructive pulmonary disease (COPD) and asthma exacerbations are associated with ill health, increased mortality, and health care costs. However, there is limited evidence regarding mortality and its predictors among patients treated for COPD and asthma exacerbations in low-income nations, particularly in Ethiopia.

Methods

A-6 month prospective observational study was conducted from April 20-September 20, 2019. Data were collected on socio-demographic, baseline clinical characteristics and outcomes of asthma and COPD exacerbations. Data were entered into Epi-Data version 4.02.01 for cleaning and exported to STATA 14.0 for analysis. Kaplan-Meier (Log-rank test) was used to compare the baseline survival experience of the study participants and Cox proportional hazard regression analysis was conducted to determine the predictors of mortality. Adjusted hazard ratios (AHRs) with two-sided p-value <0.05 were considered statistically significant.

Results

A total of 130 patients (60% males) were included. The median (interquartile range (IQR)) age of the study participants was 59(50–70) years. The median (IQR) survival time to death was 17.5 (10–26) days. The total proportion of in-hospital mortality was 10.78% (14/130), and the incidence rate of mortality was 2.56 per 1000 person-years. The duration of oxygen therapy ≥16hours/day (AHR = 6.330, 95% CI [1.092–36.679], and old age (AHR = 1.066, 95% CI [1.0001–1.136] were the independent predictors of in-hospital mortality.

Conclusion

In this study, the in-hospital mortality rate was very high. Moreover, prolonged oxygen therapy (≥16hours/day) and old age were independently associated with in-hospital mortality. Therefore, special attention should be given to recipients of prolonged oxygen therapy and the elderly during hospital stay.

End-of-Life Health Care Utilization Between Chronic Obstructive Pulmonary Disease and Lung Cancer Patients

CONTEXT

At the end of life, chronic obstructive pulmonary disease (COPD) and lung cancer (LC) patients exhibit similar symptoms; however, a large-scale study comparing end-of-life health care utilization between these two groups has not been conducted in East Asia.

OBJECTIVES

To explore and compare end-of-life resource use during the last six months before death between COPD and LC patients.

METHODS

Using data from the Taiwan National Health Insurance Research Database, we conducted a nationwide retrospective cohort study in COPD (n = 8640) and LC (n = 3377) patients who died between 1997 and 2013.

RESULTS

The COPD decedents were more likely to be admitted to intensive care units (57.59% vs 29.82%), to have longer intensive care unit stays (17.59 vs 9.93 days), and to undergo intensive procedures than the LC decedents during their last six months; they were less likely to receive inpatient (3.32% vs 18.24%) or home-based palliative care (0.84% vs 8.17%) and supportive procedures than the LC decedents during their last six months. The average total medical cost during the last six months was approximately 18.42% higher for the COPD decedents than for the LC decedents.

CONCLUSION

Higher intensive health care resource use, including intensive procedure use, at the end of life suggests a focus on prolonging life in COPD patients; it also indicates an unmet demand for palliative care in these patients. Avoiding potentially inappropriate care and improving end-of-life care quality by providing palliative care to COPD patients are necessary.

Long-term outcomes after acute hypercapnic COPD exacerbation : First-ever episode of non-invasive ventilation

BACKGROUND

Non-invasive ventilation (NIV) is used to treat acute hypercapnic respiratory failure (AHRF) in patients with chronic obstructive pulmonary disease (COPD); however, long-term outcomes following discharge are largely unknown. This study aimed to characterize long-term outcomes and identify associated markers in patients with COPD after surviving the first episode of HRF requiring NIV.

METHODS

This study retrospectively analyzed 122 patients, mean age 62 ± 8 years, 52% female and forced expiratory volume in 1 s (FEV1) predicted 30 ± 13%, admitted with an acute hypercapnic exacerbation of COPD and receiving a first-ever NIV treatment between 2000 and 2012.

RESULTS

A total of 40% of the patients required hospital readmission due to respiratory reasons within 1 year. Persistent hypercapnia leading to the prescription of domiciliary NIV, older age and lower body mass index (BMI) were risk factors for readmission due to respiratory reasons. Survival rates were 79% and 63% at 1 and 2 years after discharge, respectively. A shorter time to readmission and recurrent hypercapnic failure, lower BMI and acidemia on the first admission, as well as hypercapnia at hospital discharge were correlated with a decreased long-term survival.

CONCLUSION

Patients with COPD surviving their first episode of AHRF requiring NIV are at high risk for readmission and death. Severe respiratory acidosis, chronic respiratory failure and a lower BMI imply shorter long-term survival.

Home treatment of COPD exacerbation selected by DECAF score: a non-inferiority, randomised controlled trial and economic evaluation

Background

Previous models of Hospital at Home (HAH) for COPD exacerbation (ECOPD) were limited by the lack of a reliable prognostic score to guide patient selection. Approximately 50% of hospitalised patients have a low mortality risk by DECAF, thus are potentially suitable.

Methods

In a non-inferiority randomised controlled trial, 118 patients admitted with a low-risk ECOPD (DECAF 0 or 1) were recruited to HAH or usual care (UC). The primary outcome was health and social costs at 90 days.

Results

Mean 90-day costs were £1016 lower in HAH, but the one-sided 95% CI crossed the non-inferiority limit of £150 (CI −2343 to 312). Savings were primarily due to reduced hospital bed days: HAH=1 (IQR 1–7), UC=5 (IQR 2–12) (P=0.001). Length of stay during the index admission in UC was only 3 days, which was 2 days shorter than expected. Based on quality-adjusted life years, the probability of HAH being cost-effective was 90%. There was one death within 90 days in each arm, readmission rates were similar and 90% of patients preferred HAH for subsequent ECOPD.

Conclusion

HAH selected by low-risk DECAF score was safe, clinically effective, cost-effective, and preferred by most patients. Compared with earlier models, selection is simpler and approximately twice as many patients are eligible. The introduction of DECAF was associated with a fall in UC length of stay without adverse outcome, supporting use of DECAF to direct early discharge.

Trial registration number

Registered prospectively ISRCTN29082260.

Chronic obstructive pulmonary disease exacerbation in the intensive care unit: clinical, functional and quality of life at discharge and 3 months of follow up

Objective:

The purpose of this study was to evaluate the clinical/functional aspects and quality of life of chronic obstructive pulmonary disease patients who were discharged after an intensive care unit admission for acute respiratory failure.

Methods:

This prospective study included chronic obstructive pulmonary disease patients who were admitted to two intensive care units between December of 2010 and August of 2011 and evaluated over three visits after discharge. Thirty patients were included, and 20 patients completed the three-month follow up.

Results:

There was a significant improvement in the following: forced expiratory flow in one second (L) (1.1/1.4/1.4; p = 0.019), six-minute walk test (m) (- /232.8 /272.6; p = 0.04), BODE score (7.5/5.0/3.8; p = 0.001), cognition measured by the Mini Mental State Examination (21/23.5/23.5; p = 0.008) and quality of life measured by the total Saint George Respiratory Questionnaire score (63.3/56.8/51, p = 0.02). The mean difference in the total score was 12.3 (between visits 1 and three). Important clinical differences were observed for the symptom score (18.8), activities score (5.2) and impact score (14.3). The majority of participants (80%) reported they would be willing to undergo a new intensive care unit admission.

Conclusion:

Despite the disease severity, there was a significant clinical, functional and quality of life improvement at the end of the third month. Most patients would be willing to undergo a new intensive care unit admission.

Prehospital prognosis is difficult in patients with acute exacerbation of chronic obstructive pulmonary disease

Background

Patients with acute exacerbation of chronic obstructive pulmonary disease often require prehospital emergency treatment. This enables patients who are less ill to be treated on-site and to avoid hospital admission, while severely ill patients can receive immediate ventilatory support in the form of intubation. The emergency physician faces difficult treatment decisions, however, and prognostic tools that could assist in determining which patients would benefit from intubation and ventilator support would be helpful. The aim of the current study was to identify prehospital clinical variables associated with mortality from acute exacerbation of chronic obstructive pulmonary disease. As part of the study, we estimated the 30-day mortality for patients with this prehospital diagnosis.

Methods

A retrospective study was performed using data collected by the mobile emergency care unit in Odense, Denmark, combined with data from the patients’ medical records. Patients with the tentative diagnosis of acute exacerbation of chronic obstructive pulmonary disease between 1st July 2011 and 31st December 2013 were included in the study.

Results

Based on data from 530 patients, we found no statistically significant associations between prehospital clinical variables and mortality, apart from a minor association between older age and higher mortality. The overall 30-day mortality was 10%, while that for patients admitted to the intensive care unit was 30%.

Conclusion

No specific prehospital prognostic factors for mortality were identified. Prognostic assessment and the decision to withhold treatment for acute exacerbation of chronic obstructive pulmonary disease seem inadvisable in the prehospital setting.

Palliative care and management of troublesome symptoms for people with chronic obstructive pulmonary disease

People with advanced chronic obstructive pulmonary disease (COPD) have distressing physical and psychological symptoms, often have limited understanding of their disease, and infrequently discuss end-of-life issues in routine clinical care. These are strong indicators for expert multidisciplinary palliative care, which incorporates assessment and management of symptoms and concerns, patient and caregiver education, and sensitive communication to elicit preferences for care towards the end of life. The unpredictable course of COPD and the difficulty of predicting survival are barriers to timely referral and receipt of palliative care. Early integration of palliative care with respiratory, primary care, and rehabilitation services, with referral on the basis of the complexity of symptoms and concerns, rather than prognosis, can improve patient and caregiver outcomes. Models of integrated working in COPD could include: services triggered by troublesome symptoms such as refractory breathlessness; short-term palliative care; and, in settings with limited access to palliative care, consultation only in specific circumstances or for the most complex patients.

Predicting One-year Mortality After a "First" Hospitalization for Chronic Obstructive Pulmonary Disease: An Eight-Variable Assessment Score Tool

Several authors have studied predictors of outcomes following a hospitalization for chronic obstructive pulmonary disease (COPD); however, few have reported outcomes following a first hospitalization for COPD. The objective is to develop a predictive mortality risk model in patients surviving a first hospitalization for COPD. This is a retrospective cohort study using linked administrative and clinical data. The cohort included 1129 patients of 40-84 years, discharged alive from a hospitalization for COPD in a regional hospital (Sherbrooke, Canada) between 04/2006 and 03/2013 and to whom were prescribed at least two COPD drugs during their hospitalization. One-year mortality was analysed using logistic regression on a derivation sample and validated on a testing sample. In total, 141 (12.5%) patients died within one year from discharge of their first hospitalization for COPD. Predictors were: older age (OR (95% CI): 1.055 (1.026-1.085)), male sex (OR (95% CI): 1.474 (0.921-2.358)), having a severe COPD exacerbation (OR (95% CI): 2.548 (1.571-4.132)), higher hospital length of stay (OR (95% CI): 1.024 (0.996-1.053)), higher Charlson co-morbidity index (OR (95% CI): 1.262 (1.099-1.449)), being diagnosed of cancer (OR (95% CI): 2.928 (1.456-5.885)), the number of prior all-cause hospitalizations (OR (95% CI): 1.323 (1.097-1.595)), and a COPD duration exceeding 3 years (OR (95% CI): 1.710 (1.058-2.763)). A simple clinical prognosis tool is proposed and shows good discrimination in both the derivation and validation cohorts (c-statistic >0.78). One over eight patients discharged alive from a first COPD hospitalization will die the following year. It is thus important to identify higher-risk patients in order to plan and manage appropriate treatment.

Validation of the DECAF score to predict hospital mortality in acute exacerbations of COPD

Background

Hospitalisation due to acute exacerbations of COPD (AECOPD) is common, and subsequent mortality high. The DECAF score was derived for accurate prediction of mortality and risk stratification to inform patient care. We aimed to validate the DECAF score, internally and externally, and to compare its performance to other predictive tools.

Methods

The study took place in the two hospitals within the derivation study (internal validation) and in four additional hospitals (external validation) between January 2012 and May 2014. Consecutive admissions were identified by screening admissions and searching coding records. Admission clinical data, including DECAF indices, and mortality were recorded. The prognostic value of DECAF and other scores were assessed by the area under the receiver operator characteristic (AUROC) curve.

Results

In the internal and external validation cohorts, 880 and 845 patients were recruited. Mean age was 73.1 (SD 10.3) years, 54.3% were female, and mean (SD) FEV₁ 45.5 (18.3) per cent predicted. Overall mortality was 7.7%. The DECAF AUROC curve for inhospital mortality was 0.83 (95% CI 0.78 to 0.87) in the internal cohort and 0.82 (95% CI 0.77 to 0.87) in the external cohort, and was superior to other prognostic scores for inhospital or 30-day mortality.

Conclusions

DECAF is a robust predictor of mortality, using indices routinely available on admission. Its generalisability is supported by consistent strong performance; it can identify low-risk patients (DECAF 0–1) potentially suitable for Hospital at Home or early supported discharge services, and high-risk patients (DECAF 3–6) for escalation planning or appropriate early palliation.

Trial registration number

UKCRN ID 14214.

Critical care admission for acute medical patients

Demand for intensive care is growing. There are no contemporaneous consensus guidelines on which patients should be referred to intensive care. Prognostic scoring systems predict survival, but are of limited use for individual patients. Some groups of patients have historically been regarded as having a very high mortality after admission to intensive care, raising questions about the appropriateness of advanced organ support in these patients. We reviewed the existing literature on outcomes of patients admitted to intensive care with chronic obstructive pulmonary disease, liver cirrhosis and haematological malignancies. We identified specific markers indicating a poor prognosis in each group, and also identified common risk factors predicting a high mortality across all groups. Multiple organ failure at the time of referral to intensive care predicts a very poor outcome. Physical factors indicating a limited functional capacity also predict high mortality, suggesting that frailty has a significant impact on intensive care outcome.

Comparison of in-hospital mortality in patients with COPD, asthma and asthma-COPD overlap exacerbations

BACKGROUND AND OBJECTIVE

Obstructive airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD), have airflow limitation associated with chronic inflammation. Using a national inpatient database in Japan, we aimed to evaluate factors affecting in-hospital mortality in patients with asthma, COPD or asthma-COPD overlap (ACO).

METHODS

We retrospectively collected data for inpatients (age >40 years) with exacerbation of COPD and/or asthma in 1073 hospitals across Japan between July 2010 and May 2013. We performed multivariable logistic regression analysis to examine the association of various factors with all-cause in-hospital mortality, including diagnosis of ACO, asthma alone and COPD alone.

RESULTS

Of 30 405 eligible patients, in-hospital mortality in patients with ACO, asthma alone and COPD alone was 2.3%, 1.2% and 9.7%, respectively. COPD patients had a significantly higher mortality than ACO patients (odds ratio 1.96; 95% confidence interval: 1.38-2.79); patients with asthma alone showed lower mortality (0.70; 0.50-0.97). Higher mortality was also significantly associated with older age, male gender, lower body mass index, more severe dyspnoea, lower level of consciousness, worse activities of daily life and higher daily dose of corticosteroids.

CONCLUSION

Asthma alone was associated with lower mortality, but COPD alone was associated with higher mortality than ACO.

In-hospital and one-year mortality and their predictors in patients hospitalized for first-ever chronic obstructive pulmonary disease exacerbations: a nationwide population-based study

Introduction

Natural history of chronic obstructive pulmonary disease (COPD) is punctuated by exacerbations; however, little is known about prognosis of the first-ever COPD exacerbation and variables predicting its outcomes.

Materials and Methods

A population-based cohort study among COPD patients with their first-ever exacerbations requiring hospitalizations was conducted. Main outcomes were in-hospital mortality and one-year mortality after discharge. Demographics, comorbidities, medications and in-hospital events were obtained to explore outcome predictors.

Results

The cohort comprised 4204 hospitalized COPD patients, of whom 175 (4%) died during the hospitalization. In-hospital mortality was related to higher age (odds ratio [OR]: 1.05 per year; 95% confidence interval [CI]: 1.03–1.06) and Charlson comorbidity index score (OR: 1.08 per point; 95% CI: 1.01–1.15); angiotensin II receptor blockers (OR: 0.61; 95% CI: 0.38–0.98) and β blockers (OR: 0.63; 95% CI: 0.41–0.95) conferred a survival benefit. At one year after discharge, 22% (871/4029) of hospital survivors were dead. On multivariate Cox regression analysis, age and Charlson comorbidity index remained independent predictors of one-year mortality. Longer hospital stay (hazard ratio [HR] 1.01 per day; 95% CI: 1.01–1.01) and ICU admission (HR: 1.33; 95% CI: 1.03–1.73) during the hospitalization were associated with higher mortality risks. Prescription of β blockers (HR: 0.79; 95% CI: 0.67–0.93) and statins (HR: 0.66; 95% CI: 0.47–0.91) on hospital discharge were protective against one-year mortality.

Conclusions

Even the first-ever severe COPD exacerbation signifies poor prognosis in COPD patients. Comorbidities play a crucial role in determining outcomes and should be carefully assessed. Angiotensin II receptor blockers, β blockers and statins may, in theory, have dual cardiopulmonary protective properties and probably alter prognosis of COPD patients. Nevertheless, the limitations inherent to a claims database study, such as the diagnostic accuracy of COPD and its exacerbation, should be born in mind.

How do COPD comorbidities affect ICU outcomes?

Background and aim

Chronic obstructive pulmonary disease (COPD) patients with acute respiratory failure (ARF) frequently require admission to the intensive care unit (ICU) for application of mechanical ventilation (MV). We aimed to determine whether comorbidities and clinical variables present at ICU admission are predictive of ICU mortality.

Methods

A retrospective, observational cohort study was performed in a tertiary teaching hospital’s respiratory ICU using data collected between January 2008 and December 2012. Previously diagnosed COPD patients who were admitted to the ICU with ARF were included. Patients’ demographics, comorbidities, body mass index (BMI), ICU admission data, application of noninvasive and invasive MV (NIV and IMV, respectively), cause of ARF, length of ICU and hospital stay, and mortality were recorded from their files. Patients were grouped according to mortality (survival versus non-survival), and all the variables were compared between the two groups.

Results

During the study period, a total of 1,013 COPD patients (749 male) with a mean age (standard deviation) of 70±10 years met the inclusion criteria. Comorbidities of the non-survival group (female/male, 40/131) were significantly higher compared with the survival group (female/male, 224/618): arrhythmia (24% vs 11%), hypertension (42% vs 34%), coronary artery disease (28% vs 11%), and depression (7% vs 3%) (P<0.001, P<0.035, P<0.001, and P<0.007, respectively). Logistic regression revealed the following mortality risk factors: need of IMV, BMI <20 kg/m², pneumonia, coronary artery disease, arrhythmia, hypertension, chronic hypoxia, and higher acute physiology and chronic health evaluation II (APACHE II) scores. The respective odds ratios, confidence intervals, and P-values for each of these were as follows: 27.7, 15.7–49.0, P<0.001; 6.6, 3.5–412.7, P<0.001; 5.1, 2.9–8.8, P<0.001; 2.9, 1.5–5.6, P<0.001; 2.7, 1.4–5.2, P<0.003; 2.6, 1.5–4.4, P<0.001; 2.2, 1.2–3.9, P<0.008; and 1.1, 1.03–1.11, P<0.001.

Conclusion

Patients with severe COPD and cardiac comorbidities and cachexia should be closely monitored in ICU due to their high risk of ICU mortality.

Short- and medium-term prognosis in patients hospitalized for COPD exacerbation: the CODEX index

BACKGROUND

No valid tools exist for evaluating the prognosis in the short and medium term after hospital discharge of patients with COPD. Our hypothesis was that a new index based on the CODEX (comorbidity, obstruction, dyspnea, and previous severe exacerbations) index can accurately predict mortality, hospital readmission, and their combination for the period from 3 months to 1 year after discharge in patients hospitalized for COPD.

METHODS

A multicenter study of patients hospitalized for COPD exacerbations was used to develop the CODEX index, and a different patient cohort was used for validation. Comorbidity was measured using the age-adjusted Charlson index, whereas dyspnea, obstruction, and severe exacerbations were calculated according to BODEX (BMI, airfl ow obstruction, dyspnea, and previous severe exacerbations) thresholds. Information about mortality and readmissions for COPD or other causes was collected at 3 and 12 months after hospital discharge.

RESULTS

Two sets of 606 and 377 patients were included in the development and validation cohorts, respectively. The CODEX index was associated with mortality at 3 months ( P < .0001; hazard ratio [HR], 1.5; 95% CI, 1.2-1.8) and 1 year ( P < .0001; HR, 1.3; 95% CI, 1.2-1.5 ), hospital readmissions in the same periods, and their combination (all P < .0001). All CODEX C statistics were superior to those of the BODEX, DOSE (dyspnea, airfl ow obstruction, smoking status, and exacerbation frequency), and updated ADO (age, dyspnea, and airfl ow obstruction) indexes.

CONCLUSIONS

The CODEX index was a useful predictor of survival and readmission at both 3 months and 1 year after hospital discharge for a COPD exacerbation, with a prognostic capacity superior to other previously published indexes.

Predicting 1-year mortality rate for patients admitted with an acute exacerbation of chronic obstructive pulmonary disease to an intensive care unit: an opportunity for palliative care

The objective of this study was to develop a model to aid clinicians in better predicting 1-year mortality rate for patients with an acute exacerbation of chronic obstructive pulmonary disease admitted to the medical intensive care unit (ICU) with the goal of earlier initiation of palliative care and end-of-life communications in this patient population. This retrospective cohort study included patients from a medical ICU from April 1, 1995, to November 30, 2009. Data collected from the Acute Physiology and Chronic Health Evaluation III database included demographic characteristics; severity of illness scores; noninvasive and invasive mechanical ventilation time; ICU and hospital length of stay; and ICU, hospital, and 1-year mortality. Statistically significant univariate variables for 1-year mortality were entered into a multivariate model, and the independent variables were used to generate a scoring system to predict 1-year mortality rate. At 1-year follow-up, 295 of 591 patients died (50%). Age and hospital length of stay were identified as independent determinants of mortality at 1 year by using multivariate analysis, and the predictive model developed had an area under the operating curve of 0.68. Bootstrap analysis with 1000 iterations validated the model, age, and hospital length of stay, entered the model 100% of the time (area under the operating curve=0.687; 95% CI, 0.686-0.688). A simple model using age and hospital length of stay may be informative for providers willing to identify patients with chronic obstructive pulmonary disease with high 1-year mortality rate who may benefit from end-of-life communications and from palliative care.

Predictors of mortality in hospitalized adults with acute exacerbation of chronic obstructive pulmonary disease

RATIONALE

There is a need to identify clinically meaningful predictors of mortality following hospitalized COPD exacerbation.

OBJECTIVES

The aim of this study was to systematically review the literature to identify clinically important factors that predict mortality after hospitalization for acute exacerbation of chronic obstructive pulmonary disease (COPD).

METHODS

Eligible studies considered adults admitted to hospital with COPD exacerbation. Two authors independently abstracted data. Odds ratios were then calculated by comparing the prevalence of each predictor in survivors versus nonsurvivors. For continuous variables, mean differences were pooled by the inverse of their variance, using a random effects model.

MEASUREMENTS AND MAIN RESULTS

There were 37 studies included (189,772 study subjects) with risk of death ranging from 3.6% for studies considering short-term mortality, 31.0% for long-term mortality (up to 2 yr after hospitalization), and 29.0% for studies that considered solely intensive care unit (ICU)-admitted study subjects. Twelve prognostic factors (age, male sex, low body mass index, cardiac failure, chronic renal failure, confusion, long-term oxygen therapy, lower limb edema, Global Initiative for Chronic Lung Disease criteria stage 4, cor pulmonale, acidemia, and elevated plasma troponin level) were significantly associated with increased short-term mortality. Nine prognostic factors (age, low body mass index, cardiac failure, diabetes mellitus, ischemic heart disease, malignancy, FEV1, long-term oxygen therapy, and PaO2 on admission) were significantly associated with long-term mortality. Three factors (age, low Glasgow Coma Scale score, and pH) were significantly associated with increased risk of mortality in ICU-admitted study subjects.

CONCLUSION

Different factors correlate with mortality from COPD exacerbation in the short term, long term, and after ICU admission. These parameters may be useful to develop tools for prediction of outcome in clinical practice.

Day-to-day measurement of patient-reported outcomes in exacerbations of chronic obstructive pulmonary disease

Background

Exacerbations of chronic obstructive pulmonary disease (COPD) are a major burden to patients and to society. Little is known about the possible role of day-to-day patient-reported outcomes during an exacerbation. This study aims to describe the day-to-day course of patient-reported health status during exacerbations of COPD and to assess its value in predicting clinical outcomes.

Methods

Data from two randomized controlled COPD exacerbation trials (n = 210 and n = 45 patients) were used to describe both the feasibility of daily collection of and the day-to-day course of patient-reported outcomes during outpatient treatment or admission to hospital. In addition to clinical parameters, the BORG dyspnea score, the Clinical COPD Questionnaire (CCQ), and the St George’s Respiratory Questionnaire were used in Cox regression models to predict treatment failure, time to next exacerbation, and mortality in the hospital study.

Results

All patient-reported outcomes showed a distinct pattern of improvement. In the multivariate models, absence of improvement in CCQ symptom score and impaired lung function were independent predictors of treatment failure. Health status and gender predicted time to next exacerbation. Five-year mortality was predicted by age, forced expiratory flow in one second % predicted, smoking status, and CCQ score. In outpatient management of exacerbations, health status was found to be less impaired than in hospitalized patients, while the rate and pattern of recovery was remarkably similar.

Conclusion

Daily health status measurements were found to predict treatment failure, which could help decision-making for patients hospitalized due to an exacerbation of COPD.

What determines immediate use of invasive ventilation in patients with COPD?

BACKGROUND

The choice between non-invasive ventilation (NIV) and invasive ventilation in patients with an acute exacerbation of chronic obstructive pulmonary disease (AECOPD) may be irrational. The aim of this study was to examine those patient characteristics, and circumstances deemed important in the choice made between NIV and invasive ventilation in the intensive care unit (ICU).

METHODS

We first examined 95 admissions of AECOPD patients on nine ICUs and identified variables associated with invasive ventilation. Thereafter, a questionnaire was sent to ICU personnel to study the relative importance of different factors with a possible influence on the decision to use invasive ventilation at once.

RESULTS

Univariable analysis showed that increasing age [odds ratio (OR) 1.06 per year] and increasing body mass index (BMI) (OR 1.11 per kg/m(2) ) were associated with immediate invasive ventilation, while there was no such association with arterial blood gases or breath rate. BMI was the only factor that remained associated with immediate invasive ventilation in the multivariable analysis [OR 1.12 (95% confidence interval 1.03-1.23) kg/m(2) ]. Ranking of responses to the questionnaire showed that consciousness, respiratory symptoms and blood gases were powerful factors determining invasive ventilation, whereas high BMI and age were ranked low. Non-patient-related factors were also deemed important (physician in charge, presence of guidelines, ICU workload).

CONCLUSION

Factors other than those deemed most important in guidelines appear to have an inappropriate influence on the choice between NIV and immediate intubation in AECOPD in the ICU. These factors must be identified to further increase the appropriate use of NIV.

Invasive Mechanical Ventilation in Acute Exacerbation of COPD: Prognostic Indicators to Support Clinical Decision Making

Although non-invasive ventilation is the mainstay of management for patients with hypercapnic acute exacerbation of COPD, invasive mechanical ventilation (IMV) still has an important role to play. IMV can be used successfully to reduce mortality and still maintain quality of life in a subset of patients. Despite this, the evidence to support which patients will benefit from IMV is limited. This article reviews the literature available to guide clinician decision-making. Age is not a reliable independent predictor of survival for COPD patients receiving IMV, nor are levels of PaO2, PCO2, or use of long-term oxygen therapy. Body composition and nutritional status are independent predictors of survival and the presence of co-morbidities, such as cor pulmonale, cardiovascular disease and diabetes mellitus are negative prognostic indicators. Length of time in hospital prior to ICU admission also is an adverse prognostic factor. Although scoring systems exist, their ability to predict outcome for individual patients has limitations. Work needs to be done to improve end-of-life planning in COPD with the encouragement of discussion about advance directives when patients are reaching advanced stage of the disease.

The prognostic variables predictive of mortality in patients with an exacerbation of COPD admitted to the ICU: an integrative review

INTRODUCTION

Chronic Obstructive Pulmonary Disease (COPD) frequently presents with an acute exacerbation (AECOPD). Debate exists as to whether these patients should be admitted to intensive care units (ICUs). An integrative review was performed to determine whether clinical variables available at the time of ICU admission are predictive of the intermediate-term mortality of patients with an AECOPD.

METHODS

An integrative review was structured to incorporate a five-stage review framework to facilitate data extraction, analysis and presentation. The quality of the studies contributing to the integrative review was assessed with a novel scoring system developed from previously published data and adapted to this setting.

RESULTS

The integrative review search strategy identified 28 studies assessing prognostic variables in this setting. Prognostic variables associated with intermediate-term mortality were low Glasgow Coma Scale (GCS) on admission to ICU, cardio-respiratory arrest prior to ICU admission, cardiac dysrhythmia prior to ICU admission, length of hospital stay prior to ICU admission and higher values of acute physiology scoring systems. Premorbid variables such as age, functional capacity, pulmonary function tests, prior hospital or ICU admissions, body mass index and long-term oxygen therapy were not found to be associated with intermediate-term mortality nor was the diagnosis attributed to the cause of the AECOPD.

DISCUSSION

Variables associated with intermediate-term mortality after AECOPD requiring ICU admission are those variables, which reflect underlying severity of acute illness. Premorbid and diagnostic data have not been shown to be predictive of outcome. A scoring system is proposed to assess studies of prognosis in AECOPD.

Effects of hypercapnia and NO synthase inhibition in sustained hypoxic pulmonary vasoconstriction

Background

Acute respiratory disorders may lead to sustained alveolar hypoxia with hypercapnia resulting in impaired pulmonary gas exchange. Hypoxic pulmonary vasoconstriction (HPV) optimizes gas exchange during local acute (0-30 min), as well as sustained (> 30 min) hypoxia by matching blood perfusion to alveolar ventilation. Hypercapnia with acidosis improves pulmonary gas exchange in repetitive conditions of acute hypoxia by potentiating HPV and preventing pulmonary endothelial dysfunction. This study investigated, if the beneficial effects of hypercapnia with acidosis are preserved during sustained hypoxia as it occurs, e.g in permissive hypercapnic ventilation in intensive care units. Furthermore, the effects of NO synthase inhibitors under such conditions were examined.

Method

We employed isolated perfused and ventilated rabbit lungs to determine the influence of hypercapnia with or without acidosis (pH corrected with sodium bicarbonate), and inhibitors of endothelial as well as inducible NO synthase on acute or sustained HPV (180 min) and endothelial permeability.

Results

In hypercapnic acidosis, HPV was intensified in sustained hypoxia, in contrast to hypercapnia without acidosis when HPV was amplified during both phases. L-N^G-Nitroarginine (L-NNA), a non-selective NO synthase inhibitor, enhanced acute as well as sustained HPV under all conditions, however, the amplification of sustained HPV induced by hypercapnia with or without acidosis compared to normocapnia disappeared. In contrast 1400 W, a selective inhibitor of inducible NO synthase (iNOS), decreased HPV in normocapnia and hypercapnia without acidosis at late time points of sustained HPV and selectively reversed the amplification of sustained HPV during hypercapnia without acidosis. Hypoxic hypercapnia without acidosis increased capillary filtration coefficient (Kfc). This increase disappeared after administration of 1400 W.

Conclusion

Hypercapnia with and without acidosis increased HPV during conditions of sustained hypoxia. The increase of sustained HPV and endothelial permeability in hypoxic hypercapnia without acidosis was iNOS dependent.

Multidimensional prognostic indices for use in COPD patient care. A systematic review

Background

A growing number of prognostic indices for chronic obstructive pulmonary disease (COPD) is developed for clinical use. Our aim is to identify, summarize and compare all published prognostic COPD indices, and to discuss their performance, usefulness and implementation in daily practice.

Methods

We performed a systematic literature search in both Pubmed and Embase up to September 2010. Selection criteria included primary publications of indices developed for stable COPD patients, that predict future outcome by a multidimensional scoring system, developed for and validated with COPD patients only. Two reviewers independently assessed the index quality using a structured screening form for systematically scoring prognostic studies.

Results

Of 7,028 articles screened, 13 studies comprising 15 indices were included. Only 1 index had been explored for its application in daily practice. We observed 21 different predictors and 7 prognostic outcomes, the latter reflecting mortality, hospitalization and exacerbation. Consistent strong predictors were FEV₁ percentage predicted, age and dyspnoea. The quality of the studies underlying the indices varied between fairly poor and good. Statistical methods to assess the predictive abilities of the indices were heterogenic. They generally revealed moderate to good discrimination, when measured. Limitations: We focused on prognostic indices for stable disease only and, inevitably, quality judgment was prone to subjectivity.

Conclusions

We identified 15 prognostic COPD indices. Although the prognostic performance of some of the indices has been validated, they all lack sufficient evidence for implementation. Whether or not the use of prognostic indices improves COPD disease management or patients' health is currently unknown; impact studies are required to establish this.

Routine laboratory tests can predict in-hospital mortality in acute exacerbations of COPD

Chronic obstructive pulmonary disease (COPD) has a rising global incidence and acute exacerbation of COPD (AECOPD) carries a high health-care economic burden. Classification and regression tree (CART) analysis is able to create decision trees to classify risk groups. We analysed routinely collected laboratory data to identify prognostic factors for inpatient mortality with AECOPD from our large district hospital. Data from 5,985 patients with 9,915 admissions for AECOPD over a 7-year period were examined. Randomly allocated training (n = 4,986) or validation (n = 4,929) data sets were developed and CART analysis was used to model the risk of all-cause death during admission. Inpatient mortality was 15.5%, mean age was 71.5 (±11.5) years, 56.2% were male, and mean length of stay was 9.2 (±12.2) days. Of 29 variables used, CART analysis identified three (serum albumin, urea, and arterial pCO(2)) to predict in-hospital mortality in five risk groups, with mortality ranging from 3.0 to 23.4%. C statistic indices were 0.734 and 0.701 on the training and validation sets, respectively, indicating good model performance. The highest-risk group (23.4% mortality) had serum urea >7.35 mmol/l, arterial pCO(2) >6.45 kPa, and normal serum albumin (>36.5 g/l). It is possible to develop clinically useful risk prediction models for mortality using laboratory data from the first 24 h of admission in AECOPD.

Predicting outcomes following hospitalization for acute exacerbations of COPD

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a frequent cause of hospital admission and are associated with significant morbidity, mortality, high readmission rates and high resource utilization. More accurate prediction of survival and readmission in patients hospitalized with AECOPD should help to optimize clinical management and allocation of resources, including targeting of palliative care and strategies to reduce readmissions. We have reviewed the published retrospective and prospective studies in this field to identify the factors most likely to be of value in predicting in-hospital and post-discharge mortality, and readmission of patients hospitalized for AECOPD. The prognostic factors which appear most important vary with the particular outcome under consideration. In-hospital mortality is related most clearly to the patient's acute physiological state and to the development of acute comorbidity, while post-discharge mortality particularly reflects the severity of the underlying COPD, as well as specific comorbidities, especially cardiac disease. Important factors influencing the frequency of readmission include functional limitation and poor health-related quality of life. Large prospective studies which incorporate all the potentially relevant variables are required to refine prediction of the important outcomes of AECOPD and thus to inform clinical decision making, for example on escalation of care, facilitated discharge and provision of palliative care.