Clinical validation of a risk scale for serious outcomes among patients with chronic obstructive pulmonary disease managed in the emergency department

Ottawa Risk Scale in Predicting the Outcome of Chorionic Obstructive Pulmonary Disease Exacerbation in Emergency Department; a Diagnostic Accuracy Study

Introduction

The disposition decision is a great challenge for clinicians in managing patients with chronic obstructive pulmonary disease (COPD) exacerbation. This study aimed to evaluate the accuracy of Ottawa COPD Risk Scale (OCRS) in predicting the short-term adverse events in the mentioned patients.

Methods

This prospective diagnostic accuracy study was conducted on COPD exacerbation cases who were referred to the emergency department (ED). Patients were followed up for 30 consecutive days for adverse events including the need for intubation, non-invasive ventilation, myocardial infarction, readmission, and death from any cause, and finally the accuracy of OCRS in predicting the outcome was evaluated.

Results

362 patients with the mean age of 65.55 ± 10.65 (6- 95) years were evaluated (58.0% male). Among the patients, 164 (45.3%) cases were discharged from ED, and 198 (54.7%) were admitted to the hospital. 136 (37.6%) cases experienced at least one of the studied short-term adverse events. The mean OCSD score of this series was 1.96 ± 2.39 (0 - 10). The area under the curve of OCRS in predicting the outcome of COPD patients was 0.814 (95%CI: 0.766 - 0.862). The best cut-off point of the scale in predicting the outcome was 1.5. The sensitivity and specificity of the scale were 75.75% (95%CI: 69.6% - 81.42%) and 89.63% (95%CI: 83.67% - 93.66%), respectively. By employing this threshold, 48 (13.25%) cases would have unnecessary hospitalization, and 17 (0.04%) would be discharged incorrectly.

Conclusion

The OCRS has acceptable level of prediction accuracy in predicting the short-term adverse event of COPD patients. The use of this scoring in the routine practice of ED clinicians can lead to a reduction in unnecessary admissions and unsafe discharge for these patients.

The adjusted impact of different severities of acute exacerbations and medications on the risk of developing dementia in COPD patients

BACKGROUND

Although a relationship between chronic obstructive pulmonary disease (COPD) and dementia has been reported, the initial severity upon emergency department (ED) visits and the medications used have not been well evaluated as risk factors for increased dementia occurrence. We aimed to analyze the risks of dementia development over 5 years among patients with COPD compared to matched controls (primary) and the impact of different severities of acute exacerbations (AEs) of COPD and medications on the risk of dementia development among COPD patients (secondary).

METHOD

This study used the Taiwanese government deidentified health care database. We enrolled patients during the 10-year study period (January 1, 2000, to December 31, 2010), and each patient was followed up for 5 years. Once these patients received a diagnosis of dementia or died, they were no longer followed up. The study group included 51,318 patients who were diagnosed with COPD and 51,318 matched (in terms of age, sex, and the number of hospital visits) non-COPD patients from the remaining patients as the control group. Each patient was followed up for 5 years to analyze the risk of dementia with Cox regression analysis. Data on medications (antibiotics, bronchodilators, corticosteroids) and severity at the initial ED visit (ED treatment only, hospital admission, or ICU admission) were collected for both groups, as well as demographics and baseline comorbidities, which were considered confounding factors.

RESULTS

In the study and control groups, 1,025 (2.0%) and 423 (0.8%) patients suffered from dementia, respectively. The unadjusted HR for dementia was 2.51 (95% CI: 2.24-2.81) in the study group. Bronchodilator treatment was associated with the HRs, especially among those who received long-term (> 1 month) treatment (HR = 2.10, 95% CI: 1.91-2.45). Furthermore, among 3,451 AE of COPD patients who initially visited the ED, patients who required ICU admission (n = 164, 4.7%) had a higher risk of dementia occurrence (HR = 11.05, 95% CI: 7.77-15.71).

CONCLUSION

Bronchodilator administration might be associated with a decreased risk of dementia development. More importantly, patients who suffered AEs of COPD and initially visited the ED and required ICU admission had a higher risk of developing dementia.

Comparison of two scores for short-term outcomes in patients with COPD exacerbation in the emergency department: the Ottawa COPD Risk Scale and the DECAF score

Background

While clinical decision rules have been developed to evaluate exacerbations and decisions on hospitalisation and discharge in emergency departments (EDs) in patients with chronic obstructive pulmonary disease (COPD), these rules are not widely used in EDs. In this study, we compare the predictive efficacy of the Ottawa Chronic Obstructive Pulmonary Disease Risk Scale (OCRS) and the Dyspnea, Eosinopenia, Consolidation, Acidemia, and Atrial Fibrillation (DECAF) score in estimating the short-term poor outcome of patients in our ED with exacerbations of COPD.

Methods

This single-centre prospective observational study was conducted over 6 months. Patients with acute exacerbations of COPD admitted to the ED during the study period were included in the study. A poor outcome was defined as any of the following: readmission and requiring hospitalisation within 14 days of discharge, requiring mechanical ventilation on the first admission, hospitalisation for longer than 14 days on the first admission, or death within 30 days. The sensitivity and specificity of the OCRS and the DECAF score for a poor outcome and for mortality were calculated.

Results

Of the 385 patients who participated in the study, 85 were excluded based on the exclusion criteria. 66% of the patients were male, and the mean age was 70.15±10.36 years. A total of 20.7% of all patients (n=62) experienced poor outcomes. The sensitivity of an OCRS score <1 for predicting a poor outcome in patients was 96.8% (95% CI 88.8-99.6%) and the specificity was 18.5% (95% CI 13.8-24.0%). The sensitivity and specificity of an OCRS score <2 were 83.3% (95% CI 35.9-99.6%) and 65.5% (95% CI 59.6-70.7%), respectively. The sensitivity and specificity of a DECAF score <1 were 88.7% (95% CI 78.1-95.3%) and 34.5% (95% CI 28.4-40.9%), respectively. When the DECAF score was <2, sensitivity and specificity were 69.3% (95% CI 56.4-80.4%) and 74.8% (95% CI 68.8-80.2%), respectively.

Conclusion

Our physicians achieved high specificity but low sensitivity in predicting a poor outcome. The OCRS is the more sensitive of the two tools, while the DECAF score is more specific in predicting a poor outcome when all threshold values are evaluated. While both tools may results in unnecessary hospitalisation, they can reduce the incidence of hospital discharge of patients with exacerbations of COPD who will develop poor outcomes in the ED.

Composite Outcomes in Clinical Prediction Modeling: Are We Trying to Predict Apples and Oranges?

Composite outcomes are widely used in clinical research. Existing literature has considered the pros and cons of composite outcomes in clinical trials, but their extensive use in clinical prediction has received much less attention. Clinical prediction assists decision-making by directing patients with higher risks of adverse outcomes toward interventions that provide the greatest benefits to those at the greatest risk. In this article, we summarize our existing understanding of the advantages and disadvantages of composite outcomes, consider how these relate to clinical prediction, and highlight the problem of key predictors having markedly different associations with individual components of the composite outcome. We suggest that a "composite outcome fallacy" may occur when a clinical prediction model is based on strong associations between key predictors and one component of a composite outcome (such as mortality) and used to direct patients toward intervention when these predictors actually have an inverse association with a more relevant component of the composite outcome (such as the use of a lifesaving intervention). We propose that clinical prediction scores using composite outcomes should report their accuracy for key components of the composite outcome and examine for inconsistencies among predictor variables.

Terms and Definitions Used to Describe Recurrence, Treatment Failure and Recovery of Acute Exacerbations of COPD: A Systematic Review of Observational Studies

Introduction

Acute exacerbations of chronic obstructive pulmonary disease (AECOPDs) are important clinical events, with many patients experiencing multiple AECOPDs annually. The terms used in the literature to define recurring AECOPD events are inconsistent and may impact the ability to describe the true burden of these events. We undertook a systematic review to identify and summarize terms and definitions used in observational studies to describe AECOPD-related events occurring after an initial AECOPD (hereafter “subsequent AECOPD”).

Methods

PubMed was searched (2000–2019) for observational studies on subsequent AECOPD events using broad search strings for “COPD”, “exacerbation”, and “subsequent exacerbation events”. Only English-language studies were included. Small studies (n<50) and studies focusing on hospital re-admission only were excluded. Extracted data were analyzed descriptively to generate a narrative summary, using a thematic approach to group studies utilizing similar terms for subsequent AECOPD.

Results

Forty-seven studies were included. No single, distinct terms or definitions were used to define and identify multiple occurrences of AECOPDs, though most (46) studies used one or more of four clustered terms and definitions: reapse (n = 13), recurrence/re-exacerbation (n = 11), treatment failure (n = 12) and non-recovery/time to recovery (n = 16). Heterogeneity was observed within and between the four clusters with respect to study setting, starting point for observing subsequent AECOPDs, time frame to identify a subsequent AECOPD (except for studies using “time to recovery”), and basis for identifying a subsequent exacerbation.

Conclusion

Our review demonstrates that subsequent AECOPDs (including events such as relapse, recurrence/re-exacerbation, treatment failure, non-recovery/time to recovery) are ill-defined in the observational study literature, emphasizing the need to reach consensus on precise and objective definitions (for example, when one AECOPD ends and another begins). Use of standardized terminology and definitions may aid comparability between, and synthesis of, studies, thus improving the understanding of the natural history and burden of exacerbations in COPD patients.

Predicting Adverse Events Among Patients With COPD Exacerbations in the Emergency Department

BACKGROUND

COPD exacerbations lead to excessive health care utilization, morbidity, and mortality. The Ottawa COPD Risk Scale (OCRS) was developed to predict short-term serious adverse events (SAEs) among patients in the emergency department (ED) with COPD exacerbations. We assessed the utility of the OCRS, its component elements, and other clinical variables for ED disposition decisions in a United States population.

METHODS

We compared the OCRS and other factors in predicting SAEs among a retrospective cohort of ED patients with COPD exacerbations. We followed subjects for 30 d, and the primary outcome, SAE, was defined as any death, admission to monitored unit, intubation, noninvasive ventilation, major procedure, myocardial infarction, or revisit with hospital admission.

RESULTS

A total of 246 subjects (median 61-y old, 46% male, total admission rate to ward 52%) were included, with 46 (18.7%) experiencing SAEs. Median OCRS scores did not differ significantly between those with and without an SAE (difference: 0 [interquartile range 0-1)]. The OCRS predicted SAEs poorly (Hosmer-Lemeshow goodness of fit [H-L GOF] P ≤ .001, area under the receiver operating characteristic [ROC] curve 0.519). Three variables were significantly related to SAEs in our final model (H-L GOF P = .14, area under the ROC curve 0.808): Charlson comorbidity index (odds ratio [OR] 1.3 [1.1-1.5] per 1-point increase); triage venous P_CO2 (OR 1.7 [1.2-2.4] per 10 mm Hg increase); and hospitalization within previous year (OR 9.1 [3.3-24.8]).

CONCLUSIONS

The OCRS did not reliably predict SAEs in our population. We found 3 risk factors that were significantly associated with 30-d SAE in our United States ED population: triage P_CO2 level, Charlson comorbidity index, and hospitalization within the previous year. Further studies are needed to develop generalizable decision tools to improve safety and resource utilization for this patient population.

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.

An Ontological Approach for Early Detection of Suspected COVID-19 among COPD Patients

Recent studies on chronic obstructive pulmonary disease (COPD) patients in the context of the coronavirus 19 (COVID-19) pandemic have reported two important problems, i.e., high mortality and vulnerability among COPD patients vs. non-COPD patients. The high number of deaths are caused by exacerbations, COVID-19, and other comorbidities. Therefore, the purpose of this article is to reduce the risk factors of COPD in the COVID-19 context. In this article, we propose approaches based on adaptation mechanisms for detecting COVID-19 symptoms, to better provide appropriate care to COPD patients. To achieve this goal, an ontological model called SuspectedCOPDcoviDOlogy has been created, which consists of five ontologies for detecting suspect cases. These ontologies use vital sign parameters, symptom parameters, service management, and alerts. SuspectedCOPDcoviDOlogy enhances the COPDology proposed by a previous research project in the COPD domain. To validate the solution, an experimental study comparing the results of an existing test for the detection of COVID-19 with the results of the proposed detection system is conducted. Finally, with these results, we conclude that a rigorous combination of detection rules based on the vital sign and symptom parameters can greatly improve the dynamic detection rate of COPD patients suspected of having COVID-19, and therefore enable rapid medical assistance.