Prospective comparison of clinical prognostic scores in elder patients with a pulmonary embolism

BACKGROUND

The Geneva Prognostic Score (GPS), the Pulmonary Embolism Severity Index (PESI) and its simplified version (sPESI) are well-known clinical prognostic scores for a pulmonary embolism (PE).

OBJECTIVES

To compare the prognostic performance of these scores in elderly patients with a PE.

PATIENTS AND METHODS

In a multicenter Swiss cohort of elderly patients with venous thromboembolism, we prospectively studied 449 patients aged ≥ 65 years with a symptomatic PE. The outcome was 30-day overall mortality. We dichotomized patients as low vs. higher risk in all three scores using the following thresholds: GPS scores ≤ 2 vs. > 2, PESI risk classes I-II vs. III-V and sPESI scores 0 vs. ≥ 1. We compared 30-day mortality in low- vs. higher-risk patients and the areas under the receiver-operating characteristic curve (ROC).

RESULTS

Overall, 3.8% of patients (17/449) died within 30 days. The GPS classified a greater proportion of patients as low risk (92% [413/449]) than the PESI (36.3% [163/449]) and the sPESI (39.6% [178/449]) (P < 0.001 for each comparison). Low-risk patients based on the sPESI had a mortality of 0% (95% confidence interval [CI] 0-2.1%) compared with 0.6% (95% CI 0-3.4%) for low-risk patients based on the PESI and 3.4% (95% CI 1.9-5.6%) for low-risk patients based on the GPS. The areas under the ROC curves were 0.77 (95% CI 0.72-0.81), 0.76 (95% CI 0.72-0.80) and 0.71 (95% CI 0.66-0.75), respectively (P = 0.47).

CONCLUSIONS

In this cohort of elderly patients with PE, the GPS identified a higher proportion of patients as low risk but the PESI and sPESI were more accurate in predicting mortality.

Prognostic clinical prediction rules to identify a low-risk pulmonary embolism: a systematic review and meta-analysis

BACKGROUND

Prognostic assessment is important for the management of patients with a pulmonary embolism (PE). A number of clinical prediction rules (CPRs) have been proposed for stratifying PE mortality risk. The aim of this systematic review was to assess the performance of prognostic CPRs in identifying a low-risk PE.

METHODS

MEDLINE and EMBASE databases were systematically searched until August 2011. Derivation and validation studies that assessed the performance of prognostic CPRs in predicting adverse events-risk in PE patients were included. Weighted mean proportion and 95% confidence intervals (CIs) of adverse events were then calculated and pooled using a fixed and a random-effects model. Statistical heterogeneity was evaluated through the use of I(2) statistics.

RESULTS

Of 1125 references in the original search, 33 relevant articles were included. Nine CPRs were assessed in 37 cohorts, for a total of 35,518 patients. Pulmonary Embolism Severity Index and prognostic Geneva CPR were investigated in 22 and 6 cohorts, respectively. Eleven (29.7%) cohorts were of high quality. The median follow-up was 30 days. In low-risk PE patients, pooled short-term mortality (within 14 days or less) was 0.7% (95% CI 0.3-1.1%, random-effects model; I(2) = 49.6%), 30-day mortality was 1.7% (95% CI 1.1-2.3%, random-effects model; I(2) = 82.4%) and 90-day mortality was 2.2% (95% CI 1.2-3.4%, random-effects model; I(2) = 59.8%).

CONCLUSIONS

Prognostic CPRs efficiently identify PE patients at a low risk of mortality. Before implementing prognostic CPRs in the routine care of PE patients, well-designed management studies are warranted.

Is atrial fibrillation associated with pulmonary embolism?

BACKGROUND

A pulmonary embolism (PE) is thought to be associated with atrial fibrillation (AF). Nevertheless, this association is based on weak data.

OBJECTIVES

To assess whether the presence of AF influences the clinical probability of PE in a cohort of patients with suspected PE and to confirm the association between PE and AF.

PATIENTS/METHODS

We retrospectively analyzed the data from two trials that included 2449 consecutive patients admitted for a clinically suspected PE. An electrocardiography (ECG) was systematically performed and a PE was diagnosed by computer tomography (CT). The prevalence of AF among patients with or without a PE was compared in a multivariate logistic regression model.

RESULTS

The prevalence of PE was 22.8% (519/2272) in patients without AF and 18.8% (25/133) in patients with AF (P = 0.28). After adjustment for confounding factors, AF did not significantly modify the probability of PE (odds ratio [OR] 0.68, 95% confidence interval [CI] 0.42-1.11). However, when PE suspicion was based on new-onset dyspnea, AF significantly decreased the probability of PE (OR 0.47, 95% CI 0.26-0.84). If isolated chest pain without dyspnea was the presenting complaint, AF tended to increase the probability of PE (OR 2.42, 95% CI 0.97-6.07).

CONCLUSIONS

Overall, the presence of AF does not increase the probability of PE when this diagnosis is suspected. Nevertheless, when PE suspicion is based on new-onset dyspnea, AF significantly decreases the probability of PE, as AF may mimic its clinical presentation. However, in patients with chest pain alone, AF tends to increase PE probability.

The effects of cause of death classification on prognostic assessment of patients with pulmonary embolism

BACKGROUND

Although previous studies have provided evidence that the majority of deaths following an acute pulmonary embolism (PE) directly relate to the PE, more recent registries and cohort studies suggest otherwise.

METHODS

We assessed the cause of death during the first 30 days after the diagnosis of acute symptomatic PE in a consecutive series of patients. We also assessed the prognostic characteristics of the simplified Pulmonary Embolism Severity Index (sPESI) and cardiac troponin I (cTnI) obtained at the time of PE diagnosis.

RESULTS

During the first 30 days after diagnosis, 127 of the 1291 patients died (9.8%; 95% confidence interval [CI], 8.2-11.5). Sixty patients (4.6%; 95% CI, 3.5-5.8) died from definite or possible PE, and 67 (5.2%; 95% CI, 4.0-6.4) died from other causes (cancer 25, infection 18, hemorrhage 7, heart failure 7, chronic obstructive pulmonary disease 5, renal failure 1, seizures 1, unknown 3). The sPESI predicted all-cause (odds ratio [OR], 5.97; 95% CI, 1.74-20.54; P < 0.01) and PE-associated mortality (OR, 8.79; 95% CI, 1.12-68.79; P = 0.04). cTnI only predicted PE-associated mortality (adjusted OR, 2.39; 95% CI, 1.25-4.57; P < 0.01). For all-cause mortality, the sPESI low-risk strata had a negative predictive value of 98.8% (95% CI, 97.4-100) in comparison with 91.3% (95% CI, 88.9-93.6) for the cTnI.

CONCLUSIONS

Within the first 30 days after the diagnosis of acute symptomatic PE, death due to PE and death due to other causes occur in a similar proportion of patients. As cTnI only predicted PE-associated mortality, low-risk sPESI had a higher negative predictive value for all-cause mortality compared with cTnI.

[The unresolved issue of false-positive D-dimer results in the diagnostic workup of pulmonary embolism]

The unresolved issue of false-positive D-dimer results in the diagnostic workup of pulmonary embolism Pulmonary embolism (PE) remains a difficult diagnosis as it lacks specific symptoms and clinical signs. After the determination of the pretest PE probability by a validated clinical score, D-dimers (DD) is the initial blood test in the majority of patients whose probability is low or intermediate. The low specificity of DD results in a high number of false-positives that then require thoracic angio-CT. A new clinical decision rule, called the Pulmonary Embolism Rule-out criteria (PERC), identifies patients at such low risk that PE can be safely ruled-out without a DD test. Its safety has been confirmed in US emergency departments, but retrospective European studies showed that it would lead to 5-7% of undiagnosed PE. Alternative strategies are needed to reduce the proportion of false-positive DD results.

Prognostic value of the Geneva prediction rule in patients in whom pulmonary embolism is ruled out

OBJECTIVES

The prognosis of patients in whom pulmonary embolism (PE) is suspected but ruled out is poorly understood. We evaluated whether the initial assessment of clinical probability of PE could help to predict the prognosis for these patients.

DESIGN

Retrospective analysis of data obtained during a prospective multicentre management study.

SETTING

Six general and teaching hospitals in Belgium, France and Switzerland.

SUBJECTS

In 1334 patients in whom PE was ruled out, 3-month mortality data were available (hospital readmission status was unknown for three patients) and clinical probability was evaluated with the revised Geneva score (RGS).

MAIN OUTCOME MEASURES

Three-month mortality and readmission rates.

RESULTS

Three-month mortality and readmissions rates were 3% and 19%, respectively and differed significantly depending on the RGS-determined PE probability group (P<0.001). When compared with patients presenting with a low probability, the risk of death after 3 months was higher in cases of intermediate or high RGS-based probability {odds ratio: 8.7 [95% confidence interval (CI): 2.7-28.5] and 22.6 (95%CI: 2.1-241.2), respectively}. The readmission risk increased with PE probability group (P<0.001). The main causes of death were cancer, respiratory failure and cardiovascular failure. In total, 86% of patients with low RGS-based probability were alive and had not been readmitted to hospital, whereas other patients had a twofold increased risk of death or readmission during the 3-month follow-up. The simplified Geneva score, calculated a posteriori, gave similar results.

CONCLUSIONS

Initial assessment of clinical probability may help to stratify prognosis of patients in whom PE has been ruled out. Patients with a low probability of PE have a good prognosis. Whether patients with higher probability might benefit from more vigilant care should be evaluated.

The pulmonary embolism rule-out criteria (PERC) rule does not safely exclude pulmonary embolism

BACKGROUND

The Pulmonary Embolism Rule-out Criteria (PERC) rule is a clinical diagnostic rule designed to exclude pulmonary embolism (PE) without further testing. We sought to externally validate the diagnostic performance of the PERC rule alone and combined with clinical probability assessment based on the revised Geneva score.

METHODS

The PERC rule was applied retrospectively to consecutive patients who presented with a clinical suspicion of PE to six emergency departments, and who were enrolled in a randomized trial of PE diagnosis. Patients who met all eight PERC criteria [PERC((-))] were considered to be at a very low risk for PE. We calculated the prevalence of PE among PERC((-)) patients according to their clinical pretest probability of PE. We estimated the negative likelihood ratio of the PERC rule to predict PE.

RESULTS

Among 1675 patients, the prevalence of PE was 21.3%. Overall, 13.2% of patients were PERC((-)). The prevalence of PE was 5.4% [95% confidence interval (CI): 3.1-9.3%] among PERC((-)) patients overall and 6.4% (95% CI: 3.7-10.8%) among those PERC((-)) patients with a low clinical pretest probability of PE. The PERC rule had a negative likelihood ratio of 0.21 (95% CI: 0.12-0.38) [corrected] for predicting PE overall, and 0.63 (95% CI: 0.38-1.06) in low-risk patients.

CONCLUSIONS

Our results suggest that the PERC rule alone or even when combined with the revised Geneva score cannot safely identify very low risk patients in whom PE can be ruled out without additional testing, at least in populations with a relatively high prevalence of PE.

Validation of a clinical algorithm to identify low-risk patients with pulmonary embolism

BACKGROUND

We previously derived a clinical prognostic algorithm to identify patients with pulmonary embolism (PE) who are at low risk of short-term mortality and who could be safely discharged early or treated entirely in an outpatient setting.

OBJECTIVES

To externally validate the clinical prognostic algorithm in an independent patient sample.

METHODS

We validated the algorithm in 983 consecutive patients prospectively diagnosed with PE at an emergency department of a university hospital. Patients with none of the algorithm's 10 prognostic variables (age > or = 70 years, cancer, heart failure, chronic lung disease, chronic renal disease, cerebrovascular disease, pulse > or = 110 min(-1), systolic blood pressure < 100 mmHg, oxygen saturation < 90%, and altered mental status) at baseline were defined as being at low risk. We compared 30-day overall mortality among low-risk patients, on the basis of the algorithm, between the validation sample and the original derivation sample. We also assessed the rate of PE-related and bleeding-related mortality among low-risk patients.

RESULTS

Overall, the algorithm classified 16.3% of patients with PE as being at low risk. Mortality at 30 days was 1.9% among low-risk patients, and did not differ between the validation sample and the original derivation sample. Among low-risk patients, only 0.6% died from definite or possible PE, and 0% died from bleeding.

CONCLUSIONS

This study validates an easy-to-use, clinical prognostic algorithm for PE that accurately identifies patients with PE who are at low risk of short-term mortality. Patients who are at low risk according to our algorithm are potential candidates for less costly outpatient treatment.

Pulmonary Embolism Severity Index and troponin testing for the selection of low-risk patients with acute symptomatic pulmonary embolism

BACKGROUND

The combination of the Pulmonary Embolism Severity Index (PESI) and troponin testing could help physicians identify appropriate patients with acute pulmonary embolism (PE) for early hospital discharge.

METHODS

This prospective cohort study included a total of 567 patients from a single center registry with objectively confirmed acute symptomatic PE. On the basis of the PESI, each patient was classified into one of five classes (I-V). At the time of hospital admission, patients had troponin I (cTnI) levels measured. The endpoint of the study was all-cause mortality within 30 days after diagnosis. We calculated the mortality rates in four patient groups: group 1, PESI class I-II plus cTnI < 0.1 ng mL(-1); group 2, PESI classes III-V plus cTnI < 0.1 ng mL(-1); group 3, PESI classes I-II plus cTnI > or = 0.1 ng mL(-1); and group 4, PESI classes III-V plus cTnI > or = 0.1 ng mL(-1).

RESULTS

The study cohort had a 30-day mortality of 10% [95% confidence interval (CI), 7.6-12.5%]. Mortality rates in the four groups were 1.3%, 14.2%, 0% and 15.4%, respectively. Compared with non-elevated cTnl, the low-risk PESI had a higher negative predictive value (NPV) (98.9% vs. 90.8%) and negative likelihood ratio (NLR) (0.1 vs. 0.9) for predicting mortality. The addition of non-elevated cTnI to low-risk PESI did not improve the NPV or the NLR compared with either test alone.

CONCLUSIONS

Compared with cTnl testing, PESI classification more accurately identified patients with PE who are at low risk of all-cause death within 30 days of presentation.

[Venous thromboembolism in the elderly]

Venous thromboembolism (VTE) is a common disease and has a high impact on morbidity, mortality, and costs of care. The majority of patients with VTE are aged > or = 65 years, making VTE essentially a disease of the elderly. Despite its high prevalence and the fact that VTE has a less favourable outcome in elderly patients (e.g., higher rate of mortality, major bleeding, and post-thrombotic syndrome), older patients are underrepresented in prospective studies of VTE. Moreover, little is known about patient factors that determine medical outcomes, quality of life, and costs of care in elderly patients with VTE. The goal of this article is to review the existing evidence regarding VTE in the elderly. A prospective multicenter Swiss cohort study will examine medical outcomes, quality of life, and medical resource utilization in elderly patients with VTE.

Short-term prognosis of pulmonary embolism

Risk stratification tools that accurately quantify the prognosis of patients with pulmonary embolism (PE) may be useful in guiding medical decision making. Prospective studies demonstrated that clinical factors, echocardiographic right ventricular dysfunction, and cardiac biomarkers (troponins, brain natriuretic peptides) are independent predictors of short-term mortality in patients with PE. The presence of systemic hypotension or shock carries the highest risk of death, and thrombolysis is usually indicated. Among hemodynamically stable patients, clinical prognostic models, echocardiography, and biomarkers accurately identify low-risk patients with PE who are potential candidates for less costly outpatient care. However, the practical use of these prognostic measures is currently limited by the lack of studies demonstrating a positive impact on patient care. The benefit of risk stratification strategies based on clinical prognostic models, echocardiography, and cardiac biomarkers should be demonstrated in prospective studies before their implementation as decision aid to guide initial treatment can be recommended.

Complete venous ultrasound in outpatients with suspected pulmonary embolism

BACKGROUND

Compression ultrasonography (US) confined to the proximal veins is usually performed to detect deep vein thrombosis (DVT) in patients with suspected pulmonary embolism (PE). Recent studies suggested a limited yield of proximal US when multislice computed tomography (MSCT) was used.

OBJECTIVES

To assess whether performing an additional distal vein US would increase the diagnostic yield of the test.

PATIENTS AND METHODS

Data of 855 consecutive outpatients included in a multicenter randomized controlled trial were analyzed. Patients were investigated by a sequential diagnostic strategy including clinical probability assessment, D-dimer measurement, proximal US and MSCT. Proximal US was completed by an examination of the distal veins, the result of which was not disclosed to the physician in charge of the patient.

RESULTS

US was positive in 21% of patients, of whom 10% (53/541) had proximal DVT and 11% (59/541) isolated distal DVT. Of the 59 patients with distal DVT, 21 (36%) had no PE on MSCT. Twenty of those 21 patients were not given anticoagulant therapy and had an uneventful follow-up. The diagnostic performance of distal US for the diagnosis of PE was as follows: sensitivity 22% [95% confidence interval (CI) 17-29]; specificity 94% (95% CI 91-96); positive likelihood ratio 3.9 (95% CI 2.4-6.4).

CONCLUSIONS

In patients with suspected PE, distal US has limited diagnostic performance, and its additional use only modestly increases the yield of US. Moreover, it carries a high false-positive rate, impeding the use of distal US as a confirmatory test for PE.

Comparison of the revised Geneva score with the Wells rule for assessing clinical probability of pulmonary embolism

BACKGROUND

The revised Geneva score, a standardized clinical decision rule in the diagnosis of pulmonary embolism (PE), was recently developed. The Wells clinical decision is widely used but lacks full standardization, as it includes subjective clinician's judgement. We have compared the performance of the revised Geneva score with the Wells rule, and their usefulness for ruling out PE in combination with D-dimer measurement.

METHODS

In 300 consecutive patients, the clinical probability of PE was assessed prospectively by the Wells rule and retrospectively using the revised Geneva score. Patients comprised a random sample from a single center, participating in a large prospective multicenter diagnostic study. The predictive accuracy of both scores was compared by area under the curve (AUC) of receiver operating characteristic (ROC) curves.

RESULTS

The overall prevalence of PE was 16%. The prevalence of PE in the low-probability, intermediate-probability and high-probability categories as classified by the revised Geneva score was similar to that of the original derivation set. The performance of the revised Geneva score as measured by the AUC in a ROC analysis did not differ statistically from the Wells rule. After 3 months of follow-up, no patient classified into the low or intermediate clinical probability category by the revised Geneva score and a normal D-dimer result was subsequently diagnosed with acute venous thromboembolism.

CONCLUSIONS

This study suggests that the performance of the revised Geneva score is equivalent to that of the Wells rule. In addition, it seems safe to exclude PE in patients by the combination of a low or intermediate clinical probability by the revised Geneva score and a normal D-dimer level. Prospective clinical outcome studies are needed to confirm this latter finding.

[Complete bed rest prescription in an internal medicine ward: a dangerous treatment?]

A general knowledge led to the assumption that bed rest is beneficial for most illnesses and bed rest is prescribed in a large number of medical conditions. However, evidence from randomised studies and systematic reviews suggest a potentially harmful effect of bed rest. This review article discusses the utility of bed rest in some frequent medical pathologies such as myocardial infarction, pulmonary embolism, community acquired-pneumonia, and low back pain.

Validation of a clinical prognostic model to identify low-risk patients with pulmonary embolism

OBJECTIVE

To validate the Pulmonary Embolism Severity Index (PESI), a clinical prognostic model which identifies low-risk patients with pulmonary embolism (PE).

DESIGN

Validation study using prospectively collected data.

SETTING

A total of 119 European hospitals.

SUBJECTS

A total of 899 patients diagnosed with PE.

INTERVENTION

The PESI uses 11 clinical factors to stratify patients with PE into five classes (I-V) of increasing risk of mortality. We calculated the PESI risk class for each patient and the proportion of patients classified as low-risk (classes I and II). The outcomes were overall and PE-specific mortality for low-risk patients at 3 months after presentation. We calculated the sensitivity, specificity and predictive values to predict overall and PE-specific mortality and the discriminatory power using the area under the receiver operating characteristic curve.

RESULTS

Overall and PE-specific mortality was 6.5% (58/899) and 2.3% (21/899) respectively. Forty-seven per cent of patients (426/899) were classified as low-risk. Low-risk patients had an overall mortality of only 1.2% (5/426) and a PE-specific mortality of 0.7% (3/426). The sensitivity was 91 [95% confidence interval (CI): 81-97%] and the negative predictive value was 99% (95% CI: 97-100%) for overall mortality. The sensitivity was 86% (95% CI: 64-97%) and the negative predictive value was 99% (95% CI: 98-100%) for PE-specific mortality. The areas under the receiver operating characteristic curve for overall and PE-specific mortality were 0.80 (95% CI: 0.75-0.86) and 0.77 (95% CI: 0.68-0.86) respectively.

CONCLUSIONS

This validation study confirms that the PESI reliably identifies low-risk patients with PE who are potential candidates for less costly outpatient treatment.

[Everyday bioethics in general internal medicine]

The knowledge of the national legislation and the key concepts of bioethics are necessary for medical practice. The four principles of bioethics are autonomy, beneficence, non-maleficence, and justice. General internal medicine is the speciality of comprehensive care for often elderly patients with multiple chronic illnesses. This care is related to many ethically difficult decisions. In our article, we discuss common ethical problems in general internal medicine, including ethical aspects of the patient-physician relationship and medical decision making, the ethical significance of time management, research in bioethics and medical education.

[Clinical research in general internal medicine: present and future perspectives]

The ultimate goal of research in general internal medicine is to produce knowledge that contributes to improving patient care. Internal medicine patients, particularly those with multiple chronic illnesses, need studies that help physicians to apply existing medical knowledge to achieve the greatest medical benefit, while conserving precious health care resources. In this article, we discuss what features general internal medicine research should include to meet the needs of practicing internists and their patients. We briefly describe research topics particularly relevant to general internal medicine such as health technology assessment, quality of care studies, and studies comparing the impact of different systems of care.

[The prognosis of pulmonary embolism: are there practical implications for patient management?]

There is growing evidence that outpatient treatment is safe and effective for many patients with non-massive pulmonary embolism. Despite this evidence, the vast majority of patients with non-massive pulmonary embolism continue to be treated in an inpatient setting. A major barrier to outpatient treatment has been the lack of explicit criteria to identify patients with pulmonary embolism at low-risk of adverse medical outcome. This article discusses new risk stratification tools for pulmonary embolism such as echocardiography, biomarkers, and clinical prognostic scores, and their potential application for patient management.

Differential value of risk factors and clinical signs for diagnosing pulmonary embolism according to age

INTRODUCTION

The diagnostic value of clinical presentation of pulmonary embolism (PE) is uncertain in the elderly, who often have concomitant cardiopulmonary diseases that may mimic PE. The aim of our study was to assess the differential value of risk factors, symptoms and clinical signs of venous thromboembolism, results of electrocardiogram and chest X-ray for the diagnosis of PE in suspected patients according to age.

METHODS

We analyzed data from two outcome studies which enrolled 1721 consecutive patients presenting in the emergency department with clinically suspected PE defined as acute onset of new or worsening shortness of breath or chest pain without any other obvious etiology. All patients underwent a sequential diagnostic work-up and a 3-month follow-up.

RESULTS

The proportion of confirmed PE was 24.2% (416 of 1721). Strength of the association with PE did not differ according to age group for history of venous thromboembolism (VTE), recent surgery, tachypnea at admission or right ventricular strain on electrocardiogram. Active malignancy, hemoptysis, tachycardia, hemidiaphragmatic elevation and pleural effusion at chest X-ray were no more associated with PE in the patients aged of 75 years or more. Finally, symptoms and signs of deep venous thrombosis, and an alternative diagnosis less probable than PE were associated with PE in all age groups, but the strength of this association decreased significantly with advancing age.

CONCLUSION

Some risk factors, symptoms and signs of VTE are less strongly or even not at all associated with PE in the elderly. Physicians should take this into account when attending elderly patients suspected of PE and when assessing their clinical probability of PE.