Use of the d-dimer for Detecting Pulmonary Embolism in the Emergency Department

Apelin-13 as a novel diagnostic laboratory biomarker in thromboembolic disorders: a review of literature with prospective insights

Thromboembolic disorders, including deep vein thrombosis (DVT) and pulmonary embolism (PE), are major global health concerns, causing significant morbidity and mortality. Early diagnosis is crucial for effective treatment and improved patient outcomes. Recent research has identified Apelin-13, a bioactive peptide in the apelin family, as a promising diagnostic biomarker for Thromboembolic disorders. Apelin-13 supports vascular health by regulating protease balance through plasminogen activator inhibitors and modulating endothelial cell function. Additionally, it plays a vital role in coagulation, with elevated levels associated with an increased risk of clot formation, suggesting its utility in predicting thrombosis risk, particularly in preoperative evaluations. Findings indicate that the Apelin-13 pathway shows significant promise as a biomarker for Thromboembolic disorders, underscoring its potential therapeutic applications and the need for further investigation. This review synthesizes current literature on thromboembolic disorders and associated laboratory biomarkers, with a particular focus on Apelin-13. It examines Apelin-13's role in disease mechanisms, its physiological functions, and its potential as a diagnostic biomarker in thromboembolic conditions.

Beyond the fractures: A comprehensive Comparative analysis of Affordable and Accessible laboratory parameters and their coefficients for prediction and Swift confirmation of pulmonary embolism in high-risk orthopedic patients

Background

Pulmonary embolism (PE) poses a significant challenge in diagnosis and treatment, particularly in high-risk patient populations such as those hospitalized for orthopedic reasons. This study explores the predictive and diagnostic potential of laboratory parameters in identifying PE among orthopedic patients.

Objectives

The purpose of this study was to determine whether selected (inexpensive and readily available) laboratory parameters and their coefficients can be used to diagnose pulmonary embolism and whether they are applicable in predicting its occurrence.

Material and methods

Selected laboratory parameters were determined twice in 276 hospitalized orthopedic patients with suspected PE: PLT, MPV, NEU, LYM, D-dimer, troponin I, age-adjusted D-dimer and their coefficients. Depending on the angio-CT results, patients were divided into groups. Selected popular laboratory coefficients were calculated and statistically analyzed. Optimal cutoff points were determined for the above laboratory tests and ROC curves were plotted.

Results

D-dimer/troponin I [p = 0.008], D-dimer [p = 0.001], age-adjusted D-dimer [p = 0.007], NLR/D-dimer [p = 0.005] and PLR [p = 0.021] are statistically significant predictors of PE. D-dimer/troponin I [p < 0.001], troponin I [p = 0.005] and age-adjusted D-dimer [p = 0.001] correlated with the diagnosis of PE after the onset of clinical symptoms.

Conclusions

In the context of orthopedic patients, cost-effective laboratory parameters, particularly the D-dimer/troponin I ratio and age-adjusted D-dimer, exhibit considerable potential in predicting and diagnosing PE. These findings suggest that combining readily available laboratory tests with clinical observation can offer a viable and cost-effective diagnostic alternative, especially in resource-constrained settings. Further studies with larger and diverse patient populations are recommended to validate these results.

Evaluation of elevated serum apelin-13 and D-dimer concentrations in individuals diagnosed with pulmonary embolism

BACKGROUND

Given the limited specificity of D-dimer, there is a perceived need to discover a more precise marker for diagnosing individuals who are suspected of having pulmonary embolism (PE). In this study, by evaluating the increase in the serum level of Apelin-13 and D-dimer, we found valuable findings about Apelin-13, which can be suggested as an auxiliary and non-invasive diagnostic biomarker in individuals with suspected PE, based on the obtained results.

METHODS

In this case-control study, 52 Iranian individuals were included, all of whom were suspected to have PE. These individuals were then divided into two groups based on the results of CT angiography, which is considered the gold standard imaging method for diagnosing PE. The two groups were patients with PE and patients without PE. Finally, the levels of certain markers in the serum were compared between the two groups.

RESULTS

The mean serum D-dimer levels in patients with PE were significantly elevated (p < 0.001) in comparison to those without PE (1102.47 to 456.2 ng/ml). Furthermore, the mean level of Apelin-13 was significantly higher in patients with PE (49.8 to 73.11 ng/L) (p < 0.001). The cutoff point of Apelin-13 has been calculated at 58.50 ng/ml, with 90.9% sensitivity and 90% specificity. The D-dimer cutoff point was 500 ng/ml, with 95.5% sensitivity and 43.3% specificity.

CONCLUSIONS

Based on the results of this study, the serum level of Apelin-13 can be used as a novel diagnostic and screening biomarker in patients with pulmonary thromboembolism.

Analysis of predictive factors in children with high suspicion of pulmonary embolism

BACKGROUND AND AIM

Since there is a limited number of predictive models designed for pediatric patients with pulmonary embolism (PE), healthcare providers have resorted to utilizing the Wells criteria and PE Rule-out Criteria (PERC) that have been validated for use in adults. The objective of the study is to identify the predictive factors for PE and assess the effectiveness of the PERC, Wells, and pediatric-specific PE (PPE) criteria.

METHODS

The study included individuals between the ages of 0-18 years who underwent pulmonary CT angiography and/or ventilation-perfusion scintigraphy with suspicion of PE. Demographic characteristics, symptoms, physical examination findings, risk factors, and laboratory and imaging results were retrospectively analyzed, and PERC, Wells, and PPE criteria were applied to the study population.

RESULTS

Of the 110 patients included in the study, 27 (24.5%) had PE. Saturation, albumin, cough, calf swelling, central catheter, and malignancy were found to significantly contribute to the model. The total weighted risk score, which represents the sum of all predictive scores, ranged from 0 to 16 with a mean of 5.41 ± 4.02. When the cut-off >6.5, the model had good discrimination power for positive PE (AUC 0.79, 77% sensitivity, and 70% specificity). In our study, the Wells criteria showed a sensitivity of 96% and a specificity of 24%. The PERC exhibited a sensitivity of 96% and a specificity of 21%, while the PPE demonstrated a sensitivity of 74% and a specificity of 30%.

CONCLUSION

While the sensitivity of Wells, PERC, and PPE models was higher than our developed model, their specificities were considerably lower than our model.

The diagnostic potential of plasma SCUBE-1 concentration for pulmonary embolism: A pilot study

INTRODUCTION

This study aimed to investigate the potential application of plasma signal peptide-complement C1r/C1s, Uegf and Bmp1-epidermal growth factor domain-containing protein 1 (SCUBE-1) as a biomarker in the diagnosis of pulmonary embolism (PE).

METHODS

This cross-sectional study enrolled 177 patients who underwent PE diagnostic test and 87 healthy controls. The results of CT pulmonary angiogram (CTPA) were used as reference standards for PE diagnosis. The levels of SCUBE-1 and D-dimer in participants' plasma were detected with enzyme-linked immunosorbent assay and compared among patients with confirmed PE, suspicious PE and healthy controls. The diagnostic values were analysed using receiver operating characteristic (ROC) curve analysis. In addition, differences in plasma SCUBE-1 levels were compared among patients with different risk stratifications.

RESULTS

The plasma SCUBE-1 concentration levels in patients with CTPA confirmed PE (14.28 ± 7.74 ng/ml) was significantly higher than those in the suspicious patients (11.11 ± 4.48 ng/ml) and in healthy control (4.40 ± 3.23 ng/ml) (P < 0.01). ROC curve analysis showed that at the cut-off of 7.789 ng/ml, SCUBE-1 has significant diagnostic value in differentiating PE patients from healthy control (AUC = 0.919, sensitivity = 81.25%, specificity = 92.13%), and the performance is more accurate than D-dimer (cut-off 273.4 ng/ml, AUC = 0.648, sensitivity = 65.75%, specificity = 67.42%). The combination of D-dimer with SCUBE-1 did not further improve the diagnostic value. However, SCUBE-1 did not show significant diagnostic value in identifying PE among suspicious patients There was no significant difference in SCUBE-1 level among different risk groups (P > 0.05).

CONCLUSION

We believe that SCUBE-1 could be a potential coagulation-related marker for the diagnosis of PE.

The utility of risk assessment tools for acute pulmonary embolism in children

BACKGROUND AND AIM: Pulmonary embolism (PE) is a potentially life-threatening disease in children. The objective of the study is to evaluate the utility of adult-based pulmonary embolism rule-out criteria (PERC), Pediatric PE Model, and D-dimer in the diagnosis of PE in children.

MATERIAL AND METHODS

The study consisted of patients under 18 years of age who were consulted to the Pediatric Pulmonology Clinic for the evaluation of PE. Patients were divided into two groups based on the confirmation of PE. The group with the presence of PE (n = 20) consisted of children who were diagnosed with PE. The group with the absence of PE (n = 28) consisted of children with clinically suspected PE but negative diagnostic imaging. Adult validated clinical decision PERC rule and Pediatric PE Model were retrospectively applied to the patients.

RESULTS

In the study, PERC demonstrated a sensitivity of 60% and a specificity of 46% for the diagnosis of PE in children. When PE Model was evaluated for the children, it was found a 50% sensitivity and 75% specificity. Combining PE Model and PERC rule with D-dimer did not increase the specificity and sensitivity. Smoking was found to be relevant for PE in the childhood. Twenty-five percent of the patients had a genetic tendency for PE. All of the patients had an underlying disease as well.

CONCLUSION

None of the current risk assessment tools (PE Model, PERC, D-dimer) were found to be accurate in predicting PE. Further larger population studies are still required to develop a better diagnostic approach.

Application of the pulmonary embolism rule-out criteria (PERC rule) and age-adjusted D-Dimer in patients undergoing computed tomography pulmonary angiography for diagnosis of pulmonary embolism

Background

Diagnosis of pulmonary embolism (PE) constitutes a challenge for practitioners. Current practice involves use of pre-test probability prediction rules. Several strategies to optimize this process have been explored.

Objectives

To explore whether application of the pulmonary embolism rule-out criteria (PERC rule) and age-adjusted D-dimer (DD) would have reduced the number of computed tomography pulmonary angiography (CTPA) examinations performed in patients with suspected PE.

Methods

A retrospective cross-sectional study of adult patients taken for CTPA under suspicion of PE in 2018 and 2020. The PERC rule and age-adjusted DD were applied. The number of cases without indications for imaging studies was estimated and the operational characteristics for diagnosis of PE were calculated.

Results

302 patients were included. PE was diagnosed in 29.8%. Only 27.2% of 'not probable' cases according to the Wells criteria had D-dimer assays. Age adjustment would have reduced tomography use by 11.1%, with an AUC of 0.5. The PERC rule would have reduced use by 7%, with an AUC of 0.72.

Conclusions

Application of age-adjusted D-dimer and the PERC rule to patients taken for CTPA because of suspected PE seems to reduce the number of indications for the procedure.

A new machine learning model for predicting severity prognosis in patients with pulmonary embolism: Study protocol from Wenzhou, China

Introduction

Pulmonary embolism (PE) is a common thrombotic disease and potentially deadly cardiovascular disorder. The ratio of clinical misdiagnosis and missed diagnosis of PE is very large because patients with PE are asymptomatic or non-specific.

Methods

Using the clinical data from the First Affiliated Hospital of Wenzhou Medical University (Wenzhou, China), we proposed a swarm intelligence algorithm-based kernel extreme learning machine model (SSACS-KELM) to recognize and discriminate the severity of the PE by patient's basic information and serum biomarkers. First, an enhanced method (SSACS) is presented by combining the salp swarm algorithm (SSA) with the cuckoo search (CS). Then, the SSACS algorithm is introduced into the KELM classifier to propose the SSACS-KELM model to improve the accuracy and stability of the traditional classifier.

Results

In the experiments, the benchmark optimization performance of SSACS is confirmed by comparing SSACS with five original classical methods and five high-performance improved algorithms through benchmark function experiments. Then, the overall adaptability and accuracy of the SSACS-KELM model are tested using eight public data sets. Further, to highlight the superiority of SSACS-KELM on PE datasets, this paper conducts comparison experiments with other classical classifiers, swarm intelligence algorithms, and feature selection approaches.

Discussion

The experimental results show that high D-dimer concentration, hypoalbuminemia, and other indicators are important for the diagnosis of PE. The classification results showed that the accuracy of the prediction model was 99.33%. It is expected to be a new and accurate method to distinguish the severity of PE.

Early Diagnosis of Pulmonary Embolism Related to Clinical Presentation and Vital Signs in the Emergency Department at King Saud Medical City

Background: Pulmonary embolism (PE) is a common acute life-threatening cardiovascular disorder. It is the third most common cause of hospital-related death and early detection and management of PE are crucial. The study aimed to evaluate the association between vital signs and laboratory investigations with PE.

Methods: This is a retrospective, hospital records-based, observational study, conducted among patients who were admitted to the emergency department of King Saud Medical City in Riyadh, Saudi Arabia with a suspected diagnosis of PE during the period of March 2021 to March 2022. Data were collected by searching patients’ files and recording demographic data, and information about the clinical presentation, workup, and outcome. Data were entered and analyzed using SPSS version 26 (IBM, Armonk, NY), utilizing Chi-square statistics to test differences between groups, and logistic regression analyses to identify predictors of PE.

Results: The study included 92 patients, with a preponderance of females (70.7%), and those aged 40-60 years (51.1%). Diabetes mellitus (44.6%), and hypertension (30.4%) were the most common comorbidities among others, while shortness of breath (SOB) (83.7%), and chest pain (44.6%) were among the most commonly reported symptoms. A majority of patients had tachycardia (64.1%), while about half had low oxygen saturation (51.5%), and nearly one-third had tachypnea (29.3%), which was more predominant among those not diagnosed with PE. Logistic regression analysis revealed that SOB, respiratory rate, and oxygen saturation were the only significant predictors of PE.

Conclusion: Although being an integral part of the initial assessment in the hospital, measuring the vital signs is not always reflective of the likelihood of PE, and they should not be the only metric relied upon to make decisions about treatment approaches in patients with PE. Physicians should ensure the employment of evidence-based clinical prediction rules and guidelines when diagnosing and managing PE.

Serial use of existing clinical decisions aids can reduce computed tomography pulmonary angiography for pulmonary embolism

Pulmonary embolism (PE) remains a diagnostic challenge in emergency medicine. Clinical decision aids (CDAs) like the Pulmonary Embolism Rule-Out Criteria (PERC) are sensitive but poorly specific; serial CDA use may improve specificity. The goal of this before-and-after study was to determine if serial use of existing CDAs in a novel diagnostic algorithm safely decreases the use of CT pulmonary angiograms (CTPA). This was a retrospective before-and-after study conducted at an urban ED with 105,000 annual visits. Our algorithm uses PERC, Wells' score, and D-dimer in series, before moving to CTPA. The algorithm was introduced in January, 2017. Use of CDAs and D-dimer in the 24 months pre- and 12 months post-intervention were obtained by chart review. The algorithm's effect on CTPA ordering was assessed by comparing volume 5 years pre- and 3 years post-intervention, adjusted for ED volume. Mean CTPAs per 1000 adult ED visits was 11.1 in the 5 pre-intervention years and 9.9 in the 3 post-intervention years (p < 0.0001). Use of PERC, Wells' score and D-dimer increased from 1.1%, 1.1%, and 28% to 8.8% (p = 0.0002) 8.1% (p = 0.0005), and 35% (p = 0.0066), respectively. Pre-intervention, there were six potentially missed PEs compared to three in the post-intervention period. Introduction of our serial CDA diagnostic algorithm was associated with increased use of CDAs and D-dimer and reduced CTPA rate without an apparent increase in the number of missed PEs. Prospective validation is needed to confirm these results.

Utilization of serum D-dimer assays prior to computed tomography pulmonary angiography scans in the diagnosis of pulmonary embolism among emergency department physicians: a retrospective observational study

Background

A variety of evidence-based algorithms and decision rules using D-Dimer testing have been proposed as instruments to allow physicians to safely rule out a pulmonary embolism (PE) in low-risk patients.

Objective

To describe the prevalence of D-Dimer utilization among emergency department (ED) physicians and its impact on positive yields and utilization rates of Computed Tomography Pulmonary Angiography (CTPA).

Methods

Data was collected on all CTPA studies ordered by ED physicians at three sites during a 2-year period. Using a chi-square test, we compared the diagnostic yield for those patients who had a D-Dimer prior to their CTPA and those who did not. Secondary analysis was done to examine the impact of D-Dimer testing prior to CTPA on individual physician diagnostic yield or utilization rate.

Results

A total of 2811 CTPAs were included in the analysis. Of these, 964 CTPAs (34.3%) were ordered without a D-Dimer, and 343 (18.7%) underwent a CTPA despite a negative D-Dimer. Those CTPAs preceded by a D-Dimer showed no significant difference in positive yields when compared to those ordered without a D-Dimer (9.9% versus 11.3%, p = 0.26). At the individual physician level, no statistically significant relationship was found between D-Dimer utilization and CTPA utilization rate or diagnostic yield.

Conclusion

This study provides evidence of suboptimal adherence to guidelines in terms of D-Dimer screening prior to CTPA, and forgoing CTPAs in patients with negative D-Dimers. However, the lack of a positive impact of D-Dimer testing on either CTPA diagnostic yield or utilization rate is indicative of issues relating to the high false-positive rates associated with D-Dimer screening.

Diagnostic management of inpatients with a positive D-dimer test: developing a new clinical decision-making rule for pulmonary embolism

Background

A positive D-dimer test has high sensitivity but relatively poor specificity for the diagnosis of pulmonary embolism, causing difficulty for clinicians unskilled in pulmonary embolism diagnosis in determining whether a patient with a positive D-dimer test needs to undergo computed tomographic pulmonary angiography.

Objectives

We sought to develop a new clinical decision-making rule based on a positive D-dimer result to predict the probability of pulmonary embolism and to guide clinicians in making decisions regarding the need for computed tomographic pulmonary angiography.

Methods

We conducted a prospective, multicenter study in three hospitals in China. A total of 3014 inpatients with positive D-dimer results were included. In the derivation group, we built a multivariate logistic regression model and deduced a regression equation from which our score was derived. Finally, we validated the score in an independent cohort.

Results

Our score included nine variables (points): chest pain (1.4), chest tightness (2.3), shortness of breath (3.6), hemoptysis (3.4), heart rate ≥100 beats/min (3.6), blood gas analysis (2.9), electrocardiogram presenting a typical S1Q3T3 pattern (4.1), electrocardiogram findings (2.4), and ultrasonic cardiogram findings (3.7). The sensitivities and specificities were 100% and 86.94%, respectively, in the derivation group and 100% and 90.82%, respectively, in the validation group. Additionally, the observed and predicted proportions of patients who underwent computed tomographic pulmonary angiography were 16.82% and 10.76%, respectively, in the derivation group and 18.72% and 11.40%, respectively, in the validation group.

Conclusions

The new score can categorize inpatients with a positive D-dimer test as pulmonary embolism-likely or pulmonary embolism-unlikely, thus reducing unnecessary computed tomographic pulmonary angiography examinations.

Coronavirus Disease-2019 Pneumonia and Pulmonary Embolism: Presentation of Four Cases

Since the beginning of the Coronavirus Disease-2019 (COVID-19) outbreak, elevated D-dimer levels as an acute-phase reactant have been reported in some patients. Additionally, the patients with pneumonia are at increased risk of developing thromboembolic events. Diagnosing acute pulmonary embolism and deep vein thrombosis can be challenging in SARS-CoV2-positive patients. Here, we report four patients with COVID-19 pneumonia to highlight the possibility of acute thromboembolism in these patients. The physicians should be aware of this complication and even consider prophylactic anticoagulant therapy in proper clinical settings. How to cite this article: Alikhani F, Aalinezhad M, Haji Rezaei M, Akbari P, Hashemi M. Coronavirus Disease-2019 Pneumonia and Pulmonary Embolism: Presentation of Four Cases. Indian J Crit Care Med 2020;24(9):873-876.

Evaluation of the Diagnostic Value of Bedside Transthoracic Ultrasonography (TTUS) and Lower Extremity Three-Points Compression Duplex in the Diagnosis of the Pulmonary Embolism

Background:

The present study aimed at evaluating the diagnostic value of lung transthoracic ultrasonography (TTUS) and lower extremity sonography versus computed tomography pulmonary angiography (CTPA) in the diagnosis of pulmonary embolus (PE).

Materials and Methods:

This study was performed on 104 patients with clinically suspected PE. CTPA and D-dimer was performed on all patients. Wells’ deep vein thrombosis criteria (WDVTC) was evaluated and recorded at the patient’s admission. Finally, the results of adding venous and lung sonography scores to the WDVTC with and without the results of D-dimer test were analyzed for predicting the diagnosis of PE.

Results:

There were 104 patients clinically suspected of having a PE and enrolled in the study. A PE was confirmed in 37.5% of this cohort. WDVTC had a sensitivity and specificity of 94.87% and 80.00%, respectively, to predict PE. When adding D-dimer to the WDVTC for patients unlikely to have a PE (WDVTC≤4), the sensitivity and specificity of positive D-dimer in diagnosis of PE were 94.87% and 56.92%, respectively ( P < .001).

Conclusion:

According to these study results, the modification of the WDVTC along with the results of lung TTUS and lower extremity venous sonogram significantly increase the diagnostic power for PE.

Retrospective Analysis of the Computed Tomography Pulmonary Angiogram Utilization Patterns in the Emergency Department

OBJECTIVES

Guidelines and high-quality studies recommend using clinical decision-making (CDM) tools over clinical gestalt when evaluating a patient for pulmonary embolism. The purpose of this study is to investigate our computed tomography pulmonary angiogram (CTPA) utilization patterns and identify causal factors.

METHODS

A retrospective cohort study of CTPA studies ordered by emergency physicians in January, April, July, and October 2017 was undertaken. All necessary information to categorize patients by Wells' score, revised Geneva score, and pulmonary embolism rule-out criteria (PERC) was collected. In addition, various bloodwork, chest radiograph, and computed tomography results were collected. This data was analysed by the Pearson chi-square test or Fisher's exact test for categorical data and independent-samples t test for continuous variables.

RESULTS

A total of 510 CTPA studies were performed, with a mean age was 61.6 and a 50.6% female population. 136 studies (26.7%) failed to appropriately follow any CDM tool. CDM tool failure rate was dependent on whether the study was ordered from a community (14.9%) or tertiary hospital (University of Alberta Hospital, 27.9% and Royal Alexandra Hospital, 24.6%) (P = .038). Of these 136 studies, 31 were low/moderate risk and the d-dimer was negative. The remainder were either PERC-negative or low/moderate risk without d-dimer performed. The cumulative positive pulmonary embolism rate was 12.5%. With utilization of a CDM tool, the positive pulmonary embolism rate was 15.0%, compared to 5.9% when using gestalt (P = .026).

CONCLUSIONS

This study confirms a high rate of CDM tool use failure, and a higher positive CTPA rate for CDM tools compared to clinical gestalt.

Age-dependent diagnostic accuracy of clinical scoring systems and D-dimer levels in the diagnosis of pulmonary embolism with computed tomography pulmonary angiography (CTPA)

OBJECTIVE

The aim of this study was to compare the age-dependent diagnostic performance of clinical scores and D-dimer testing to identify patients with suspected pulmonary embolism (PE).

METHODS

Consecutive patients with suspected PE referred from the emergency department for computed tomography pulmonary angiography (CTPA) were retrospectively evaluated. Diagnostic scores (classic Wells score (WS), modified WS, simplified WS, revised Geneva score (GS), simplified GS, and YEARS score) were calculated from medical records. Results of D-dimer testing were retrieved from the laboratory database. CTPA was the diagnostic reference standard. Four age groups were analyzed (< 50, 50-64, 65-74, and ≥ 75 years). Statistical analysis used receiver operating characteristics as well as uni- and multivariate analyses with calculation of prediction models. The study was IRB approved.

RESULTS

One thousand consecutive patients were included. Areas under the curve (AUC) and accuracies were superior in patients < 50 years. For the classic WS, the AUC decreased by 11% with the optimal cutoff dropping 1.5 points in patients ≥ 75 years; for D-dimer levels, the optimal cutoff was 900 μg/L higher in both ≥ 65 years groups with a max. decrease of the AUC of 9%. In terms of accuracy, the YEARS score performed best across all groups. Classic WS and D-dimer level showed a significant interaction with patient age in prediction models.

CONCLUSION

D-dimer measurement and clinical scores perform best in patients < 50 years. The YEARS score performs best across all age groups and is therefore recommended.

KEY POINTS

• The probability of pulmonary embolism predicted by fibrin fibrinogen degradation products and clinical scores shows the highest accuracy in patients < 50 years. • The probability of pulmonary embolism predicted by the YEARS score shows the highest accuracy in each age group. • Classic Wells score and fibrin fibrinogen degradation products show a significant interaction with patient age in a logistic regression model.

Independent factors associated with pneumonia among hospitalized patients with acute exacerbations of chronic obstructive pulmonary disease

Acute exacerbations (AE) affect the prognosis of hospitalized patients with chronic obstructive pulmonary disease (COPD). Pneumonia further affects their prognosis and early diagnosis of pneumonia in AECOPD is important to initiate treatments. This study aimed to examine the differences between hospitalized AECOPD patients with and without pneumonia in order to identify risk factors of pneumonia among hospitalized patients with AECOPD.This was a retrospective case-control study of patients with COPD hospitalized at the respiratory ward of Beijing Shijitan Hospital, Capital Medical University, from October 2010 to October 2013. Patients were divided into the pneumonia and nonpneumonia groups based on exudations or opacities on chest computed tomography (CT) at admission. Data were analyzed using the chi-square test and independent 2-sample ANOVA in SPSS 20.0. Logistic regression analysis was used to identify the factors independently associated with pneumonia. P < .05 was considered statistically significant.A total of 164 patients were included. Smoking history (OR = 2.646, 95%CI 1.153-6.074, P = .022), use of drugs during the stable stage (OR = 0.435, 95%CI 0.216-0.877, P = .020), D-dimer levels (OR = 1.001, 95%CI 1.000-1.002, P = .049), percentage of neutrophils (OR = 0.271, 95%CI 0.078-0.940, P = .040), and magnitude of neutrophils increase (OR = 0.946, 95%CI 0.896-0.999, P = .046) were independently associated with pneumonia in patients with AECOPD. For severe and very severe COPD patients, smoking history (OR = 4.426, 95%CI 1.458-13.435, P = .009), use of drugs during the stable stage (OR = 0.384, 95%CI 0.168-0.877, P = .042), and fever (OR = 0.426, 95%CI 0.187-0.969, P = .023) were independently associated with pneumonia.Smoking history, use of drugs during the stable stage, and percentage of neutrophils are independently associated with CT-diagnosed pneumonia among hospitalized AECOPD patients.