Abstract
Background
This retrospective study aimed to investigate the prognostic value of the neutrophil-to-lymphocyte ratio (NLR) and albumin for 30-day mortality in patients with postoperative acute pulmonary embolism (PAPE).
Methods
We retrospectively reviewed the medical records of 101 patients with PAPE admitted from September 1, 2012, to March 31, 2019. The characteristics, surgical information, admission examination data and mortality within 30 days after PAPE were obtained from our electronic medical recording system and follow-up. The associations between the NLR, PLR, and other predictors and 30-day mortality were analyzed with univariate and multivariate analyses. Then, the nomogram including the independent predictors was established and evaluated.
Results
Twenty-four patients died within 30 days, corresponding to a 30-day mortality rate of 23.8%. The results of the multivariate analysis indicated that both the NLR and albumin were independent predictors for 30-day mortality in patients with PAPE. The probability of death increased by approximately 17.1% (OR = 1.171, 95% CI: 1.073–1.277, P = 0.000) with a one-unit increase in the NLR, and the probability of death decreased by approximately 15.4% (OR = 0.846, 95% CI: 0.762c–0.939, P = 0.002) with a one-unit increase in albumin. The area under the curve of the nomogram was 0.888 (95% CI: 0.812–0.964).
Conclusion
Our findings showed that an elevated NLR and decreased albumin were related to poor prognosis in patients with PAPE. The NLR and albumin were independent prognostic factors for PAPE.
Keywords: Neutrophil-to-lymphocyte ratio, Albumin, Mortality, Postoperative acute pulmonary embolism
Background
Postoperative acute pulmonary embolism (PAPE) is one of the most dangerous complications following operations, with an incidence between 0.9 and 3.1% [1–4]. Although the methods of diagnosis and treatment of PAPE have been continuously developed in recent years, including imaging diagnosis, interventional surgery and medicinal chemotherapy, the overall survival rate of patients with PAPE is extremely low. It was reported that the short-term mortality of patients with PAPE was between 10 and 23.1% [5–9]. Therefore, identifying the preoperative risk factors associated with mortality may help to direct more aggressive treatment strategies, such as fibrinolytic therapy, towards patients who will derive the greatest benefit.
The mechanism of inflammatory reactions is closely related to the occurrence and development of thromboembolism [10]. In recent years, many researchers have reported that some predictors based on inflammation are associated with prognosis in patients with pulmonary embolism, such as the neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), red blood cell distribution width (RDW), and C-reactive protein (CRP) [11–14]. In addition, the relationship between nutritional status and prognosis in patients with pulmonary embolism has also been extensively studied in a previous study [15]. Plasma albumin is one of the important indicators reflecting systemic nutritional status and is associated with prognosis in patients with acute pulmonary embolism [16]. However, previous studies have focused on nonsurgical patients, and no studies have focused on the relationship between these predictors and mortality in patients with PAPE. Therefore, this study was performed to investigate the relationship of admission NLR, plasma albumin and other predictors with 30-day mortality in patients with PAPE.
Methods
Patients
We performed a single-center, retrospective and case-control study. The medical records of consecutive patients who were diagnosed with pulmonary embolism from September 1, 2012, to March 31, 2019, in our hospital were reviewed, and patients who were diagnosed with acute pulmonary embolism within 90 days postoperatively were included in this study. In the present study, only patients with pulmonary embolism confirmed by computed tomography pulmonary angiography (CTPA) were defined as pulmonary embolism patients, and patients with suspected but unconfirmed pulmonary embolism by examination were not defined as pulmonary embolism patients. Patients were excluded if they underwent cardiac surgery, did not have complete data, had received blood transfusion within 1 month preoperatively, had comorbid infection, and had comorbid hematological disease or received immunosuppressive therapy within 1 month preoperatively. Finally, 101 patients met our inclusion criteria. All patients with PAPE met the diagnostic criteria of the 2014 ESC guidelines on the diagnosis and management of acute pulmonary embolism [17].
Data collection
Data were extracted from the hospital electronic database by two independent doctors. If controversial data were encountered, the two doctors who collected the data underwent discussion to reach an agreement. All patients’ characteristics (sex, age, BMI, smoking history and drinking history), comorbidities (hypertension, diabetes, respiratory diseases, chronic coronary heart disease, chronic arrhythmia, history of stroke and chronic renal failure), surgical information (surgical type and ASA level), admission examination data (neutrophil-to-lymphocyte ratio; platelet-to-lymphocyte ratio; monocyte-to-lymphocyte ratio; hemoglobin; white blood cell; platelet; mean platelet volume; platelet distribution width; red cell distribution width; glucose; neutrophil; lymphocyte; creatinine and albumin) and the situation within 30 days after PAPE were obtained through our electronic medical recording system and follow-up. Complete blood counts (CBCs), blood glucose levels, and albumin assessments were carried out at the biochemistry laboratory of our hospital. The NLR was obtained by dividing the absolute neutrophil counts by the absolute lymphocyte counts from the same blood sample, the PLR was obtained by dividing the absolute platelet counts by the absolute lymphocyte counts from the same blood sample, and the MLR was obtained by dividing the absolute monocyte counts by the absolute lymphocyte counts from the same blood samples. All test results were obtained from the same blood sample test within 3 days before surgery.
Statistical analysis
Data analysis was performed using the Statistical Package for the Social Sciences version 25.0 for Windows (IBM, Chicago, IL, USA). Data with a normal distribution are represented as the mean ± standard deviation, and Student’s t-test was used to compare two groups. The data with an abnormal distribution are represented as medians (interquartile ranges), and the Mann-Whitney U test was used to compare two groups. Categorical variables are represented as numbers or percentages, and the χ2 test or Fisher’s exact test was performed for categorical variables. Based on the univariate analysis, variables with a P value < 0.05 were included in the multivariate logistic regression analysis to confirm the independent risk factors. Forward logistic regression analysis was conducted to estimate the OR and 95% CI for 30-day mortality of the NLR, albumin and other parameters after adjusting for potential confounding factors. The receiver operating characteristic (ROC) curve was used to examine the performance of independent risk factors in predicting 30-day mortality. The area under the curve (AUC) was derived from the ROC curve, which ranged from 0.5 to 1.0 – with higher values indicating higher discriminatory ability, and the Youden Index (maximum [sensitivity +specificity] minus 1) was adopted to define the optimal cut-off value. Afterwards, a nomogram based on the independent predictors was established, and the calibration curve and decision curve analysis (DCA) were generated to evaluate the nomogram. In addition, the AUC of the nomogram was calculated, and the differences in the AUC between the nomogram and independent predictors were compared by the pROC package in R software (version 3.6.1). All P values < 0.05 were accepted as statistically significant.
Results
Baseline
During the study period, 125 patients were diagnosed with pulmonary embolism within 90 days after noncardiac surgery. Twenty-four patients were excluded because they did not meet our criteria for hematological disease (2 cases), received blood transfusion within 1 month preoperatively (13 cases), had an infection (2 cases), received immunosuppressive therapy within 1 month preoperatively (1 case) and had missing data (6 cases). Finally, 101 patients with PAPE following noncardiac surgery met our inclusion criteria and were included in this study, which included 41 males and 60 females, and the median age was 64 years (interquartile range: 57.50–71.00 years). For 101 patients, the median time of PAPE was 3 days (interquartile range: 1–5 days). Seven patients were diagnosed with massive pulmonary embolism: ten patients received fibrinolytic therapy, and the remaining patients received anticoagulant therapy. The demographic data and clinical data of deaths and survivors are listed in Table 1.
Table 1.
Comparison of baseline and comorbidities between deaths and survivors
| Total(n = 101) | Deaths(n = 24) | Survivors(n = 77) | P | |
|---|---|---|---|---|
| Age, yr | 64.00 (57.50–71.00)a | 67.00 (59.00–75.75) a | 63.00 (57.00–70.00) a | 0.200 |
| Sex (Female) | 60 | 12 | 48 | 0.283 |
| BMI, kg/m2 | 25.85 ± 3.68 | 24.54 ± 4.10 | 26.31 ± 3.59 | 0.050 |
| Smoking history | 23 | 6 | 17 | 0.766 |
| Drinking history | 19 | 4 | 15 | 0.758 |
| Surgical type | 0.861 | |||
| Musculoskeletal | 45 | 12 | 33 | |
| Abdominal | 28 | 7 | 21 | |
| Respiratory | 10 | 2 | 8 | |
| Gynecologic | 8 | 2 | 6 | |
| Neurosurgery | 5 | 1 | 4 | |
| Vascular | 5 | 0 | 5 | |
| ASA | 0.787 | |||
| II | 65 | 16 | 49 | |
| III | 36 | 8 | 28 | |
| Admission SBP | 120.00 (135.00,150.00)a | 124.50 (133.50,149.25)a | 120.00 (136.00,151.00)a | 0.873 |
| Comorbidities | ||||
| Hypertension | 38 | 9 | 29 | 0.989 |
| Diabetes | 15 | 2 | 13 | 0.484 |
| Coronary heart disease | 19 | 4 | 15 | 0.993 |
| Respiratory diseases | 9 | 1 | 8 | 0.600 |
| Arrhythmia | 4 | 1 | 3 | 1.000b |
| History of stroke | 7 | 2 | 5 | 1.000 |
| Renal failure | 1 | 1 | 0 | 0.238b |
aInterquartile range
bFisher’s Exact test
BMI Body mass index, SBP Systolic blood pressure
Prognostic factors of PAPE
Twenty-four patients died within 30 days, corresponding to a 30-day mortality rate of 23.8%. There were no significant differences in terms of age, sex, BMI, smoking history, drinking history, admission systolic blood pressure, surgical type or ASA level (all P values>0.05). There were no significant differences in terms of hypertension, diabetes, respiratory diseases, coronary heart disease, arrhythmia, history of stroke or renal failure (all P values>0.05). The baseline characteristics and comorbidities of the patients are shown in Table 1. The preoperative laboratory parameters are presented in Table 2. The NLR, neutrophil count and creatinine level were significantly higher in those who died than in survivors with PAPE (all P values < 0.05), and the albumin level was significantly lower in those who died than in survivors after PAPE (P = 0.008). There were no significant differences in the other parameters included in our research (Table 2).
Table 2.
Comparison of admission laboratory data between deaths and survivors
| Deaths(n = 24)* | Survivors(n = 77)* | P | |
|---|---|---|---|
| NLR | 14.13 (7.67–23.04) | 5.93 (2.60–8.70) | 0.000 |
| PLR | 230.00 (102.25–396.24) | 157.29 (103.99–243.52) | 0.193 |
| MLR | 0.80 (0.44–1.27) | 0.44 (0.31–0.77) | 0.004 |
| WBC, × 109/L | 13.84 (8.80–17.47) | 9.74 (6.62–12.71) | 0.001 |
| Neutrophil, ×109/L | 12.21 (8.04–15.85) | 6.20 (3.98–9.91) | 0.000 |
| Lymphocyte, ×109/L | 0.82 (0.51–1.59) | 1.21 (0.90–1.82) | 0.017 |
| Monocyte, ×109/L | 0.63 (0.36–0.89) | 0.63 (0.45–0.99) | 0.621 |
| PLT, ×109/L | 163.50 (131.25–215.25) | 199.00 (141.00–247.00) | 0.273 |
| MPV, fL | 10.15 (9.30–10.78) | 10.10 (9.40–10.88) | 0.631 |
| PDW | 12.75 (11.28–15.80) | 13.25 (10.73–16.08) | 0.990 |
| Hb, g/L | 121.00 (108.25–141.50) | 108.00 (90.00–119.00) | 0.795 |
| RDW | 13.15 (12.73–15.33) | 13.20 (12.45–14.35) | 0.369 |
| Creatinine, μmol/L | 84.40 (71.72–106.50) | 72.00 (59.75–87.00) | 0.023 |
| GLU, mmol/L | 8.19 (6.95–13.83) | 7.60 (5.56–9.92) | 0.054 |
| Albumin, g/L | 32.33 (27.37–35.69) | 38.20 (32.49–45.80) | 0.008 |
*All variables are describe as median and interquartile range
NLR neutrophil-to-lymphocyte ratio, PLR platelet to lymphocyte ratio, WBC white blood cell, MLR monocyte-to-lymphocyte ratio, PLT platelet, MPV mean platelet volume, PDW platelet distribution width, Hb hemoglobin, RDW red cell distribution width, GLU glucose
To further confirm the independent risk factors for mortality after PAPE, multivariate logistic analysis was performed. The NLR, MLR, WBC, neutrophil, lymphocyte, creatinine, and albumin (all P values<0.05) were included in the multivariate analysis, and the results indicated that both the NLR and albumin were independent predictors of 30-day mortality in patients with PAPE. The probability of death increased by approximately 17.1% (OR = 1.171, 95% CI: 1.073–1.277, P = 0.000) with a one-unit increase in the NLR, and the probability of death decreased by approximately 15.4% (OR = 0.846, 95% CI: 0.762c–0.939, P = 0.002) with a one-unit increase in albumin (Table 3). In addition, the results indicated that creatinine, the MLR, neutrophil, lymphocyte and WBC were no longer independent predictors in multivariate analysis (all P values > 0.05).
Table 3.
Multivariate regression results of 30-days mortality
| B | SE | Wald | OR | 95% CI | P | |
|---|---|---|---|---|---|---|
| Albumin | −0.167 | 0.053 | 9.881 | 0.846 | 0.762–0.939 | 0.002 |
| NLR | 0.158 | 0.044 | 12.644 | 1.171 | 1.073–1.277 | 0.000 |
NLR neutrophil-to-lymphocyte ratio
Development of a nomogram
Based on the independent predictors, a nomogram was established to predict 30-day mortality in PAPE patients (Fig. 1). The AUC of the nomogram was 0.888 (95% CI: 0.812–0.964), which was significantly higher than that of any single predictor (P value< 0.05) (Table 4 and Figs. 2 and 3a). Moreover, the calibration curve is shown in Fig. 2b, and the results indicated that the prediction by the nomogram was highly consistent with the actual observations. In addition, the DCA indicated that if the threshold probability of a patient and a doctor was between 5 and 75%, this nomogram predicted 30-day mortality with more benefit than the scheme(Fig. 2c).
Fig. 1.
A nomogram incorporating the NLR and albumin for predicting 30-day mortality in patients with postoperative acute pulmonary embolism
Table 4.
Values of predicators in predicting 30-days mortality
| Predicators | AUC | 95% CI for AUC | P | Cut-off | Sensitivity | Specificity |
|---|---|---|---|---|---|---|
| NLR | 0.823 | 0.729–0.917 | 0.000 | 12.00 | 0.625 | 0.909 |
| Albumin | 0.768 | 0.668–0.868 | 0.000 | 36.66 | 0.571 | 0.875 |
AUC area under the curve, NLR neutrophil-to-lymphocyte ratio
Fig. 2.
Receiver operating characteristic curve, calibration curve, and decision curve analysis of the nomogram. a. The area under the receiver operating characteristic curve was 0.888 (95% CI: 0.812–0.964); b. The calibration curve showed that the nomogram-predicted probability of death was highly consistent with the actual probability of death; c. The decision curve analysis indicated that if the threshold probability of a patient and a doctor was between 5 and 75%, this nomogram predicted 30-day mortality with more benefit than the scheme
Fig. 3.
Receiver operating characteristic curve of the nomogram, the NLR, and albumin. a. The area under the receiver operating characteristic curve of the nomogram was significantly higher than the area under the receiver operating characteristic curve of the NLR. b. The area under the receiver operating characteristic curve of the nomogram was significantly higher than the area under the receiver operating characteristic curve of albumin
Discussion
PAPE is one of the most dangerous complications following operations, and it is necessary to predict the prognosis of patients early. To the best of our knowledge, this is the first study to investigate predictors and establish a nomogram of 30-day mortality among patients with PAPE following noncardiac surgery. The primary findings of our study were that the NLR was significantly higher in non-surviving patients than in survivors and that plasma albumin was significantly lower in those who died than in survivors; both the NLR and albumin were independent predictors for 30-day mortality among patients with PAPE following noncardiac surgery. Moreover, the nomogram based on the NLR and albumin showed good performance in predicting 30-day mortality in patients with PAPE.
In our research, 101 patients were included, and 24 patients died within 30 days, corresponding to a 30-day mortality rate of 23.8%. According to previous studies, the mortality rate of APE patients ranges from 8.1–25.3% [12, 18–20]. Our results showed that the mortality of our cohort was within this range. In our research, the NLR was identified as an effective prognostic biomarker for PAPE patients. The NLR is the comprehensive presentation of systemic inflammation and the balance between neutrophils and lymphocytes in CBCs. Previous studies have shown that an elevated NLR is associated with an increased rate of hospital mortality among patients with acute pulmonary embolism [13], acute exacerbation of chronic obstructive pulmonary disease [21], and acute type A aortic dissection [22]; of 30-day mortality among patients with acute pulmonary embolism [19], acute kidney injury [23], ST-elevation myocardial infarction [24], and intracerebral hemorrhage [25, 26]; and of long-term mortality among patients with ST-elevation myocardial infarction [27], breast cancer [28] and epithelial ovarian cancer [29].
The link between inflammation and pulmonary embolism has been well investigated, although the underlying mechanism is not completely understood. The relationship between them may be linked by cytokines, proinflammatory cytokines, and acute-phase proteins, such as CRP, IL-8, and tumor necrosis factor, which promote the procoagulant state and play an important role in the progression of venous thromboembolism by inducing the expression of tissue factors. In addition, it has recently been reported that inflammatory mediators, such as polyphosphates and bradykinin, can directly activate contact systems and initiate external coagulation pathways [30–32]. In our research, we found that the NLR was an independent predictor of 30-day mortality in patients with PAPE, and the area under the curve of the NLR was 0.823. Therefore, we concluded that the NLR is a simple and effective prognostic predictor for patients with PAPE.
We also found that albumin was significantly lower in those who died than in survivors. To our knowledge, this is the first study to indicate the relationship between albumin and mortality in patients with PAPE. Albumin is an indicator of the nutritional status of patients and can regulate the anticoagulation system to some extent. Hypoproteinemia has been confirmed to be associated with mortality in patients with acute pulmonary embolism in previous studies [16]. In a previous study, the mechanism of the association between albumin and mortality was partly explained. Plasma albumin can interact with NO to some extent and generate S-nitrosoproteins, which then promote vasomotor activity and inhibit platelet aggregation. When albumin levels drop, the effect will be weakened [33, 34]. In addition, plasma albumin has important antioxidant, anti-inflammatory and drug carrier effects in human physiological functions [35]. Therefore, a lower plasma albumin concentration will inevitably lead to a decrease or loss of these effects.
There were also some limitations in our research. First, as a single-center study, only 101 patients met the criteria and were included in our study, which was a small sample size. The small sample size makes it impossible to classify and discuss patients with PAPE for specific operations, such as arthroplasty and gastrointestinal cancer resection. Second, although the nomogram showed good performance in terms of the AUC, calibration curve and DCA, independent validation is needed. Finally, as a retrospective study, our research had its own limitations, and some potential predictors were not included in our research. We hope that multicenter and prospective research can be performed to confirm our conclusion in the future.
Conclusions
Both the NLR and albumin were independent predicators for 30-day mortality among patients with acute pulmonary embolism following noncardiac surgery, and the NLR and albumin were better predictors together than separately. This enables assessing the severity of PAPE and can guide the clinical management of PAPE.
Acknowledgements
We would like to thank all the staff in Department of Orthopaedic, Affiliated Hospital of Chengde Medical University for their contribution on our research.
Abbreviations
- PAPE
Postoperative acute pulmonary embolism
- NLR
Neutrophil-to-lymphocyte ratio
- MLR
Monocyte-to-lymphocyte ratio
- RDW
Red blood cell distribution width
- CRP
C-reactive protein\
- CBC
Complete blood count
- ROC
-
Receiver operating characteristic curve
AUC
Area under the curve
- DCA
Decision curve analysis
- LMR
Lymphocyte to monocyte ratio
Authors’ contributions
CL, CLZ, CH, HLZ, and ZHH made substantial contributions to the design of this study; CL, CH, MYZ, CLZ, and YXT collected and analyzed the data; CL, ZYF, and GYM wrote the manuscript; CLZ and GYM revised the manuscript. All authors read and approved the final manuscript.
Funding
We received no external funding for this study.
Availability of data and materials
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
Ethics approval and consent to participate
This study was approved by the Institutional Review Board of Affiliated Hospital of Chengde Medical University. Written informed consent was obtained from all patients. No children (under 16 years old) were included in this study.
Consent for publication
Not applicable.
Competing interests
All authors declare that they have no competing interests.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Chuan Liu and Hui-lu Zhan contributed equally to this work.
Contributor Information
Cheng-Liang Zhao, Email: 38221965@qq.com.
Gui-Yun Ma, Email: maguiyun3778@163.com.
References
- 1.Rinaldo L, Brown DA, Bhargav AG, Rusheen AE, Naylor RM, Gilder HE, Monie DD, Youssef SJ, Parney IF. Venous thromboembolic events in patients undergoing craniotomy for tumor resection: incidence, predictors, and review of literature. J Neurosurg. 2019:1–12. [DOI] [PMC free article] [PubMed]
- 2.De la Garza RR, Longo M, Gelfand Y, Echt M, Kinon MD, Yassari R. Timing of prophylactic anticoagulation and its effect on thromboembolic events after surgery for metastatic tumors of the spine. Spine. 2019;44(11):E650–e655. doi: 10.1097/BRS.0000000000002944. [DOI] [PubMed] [Google Scholar]
- 3.Rottenstreich A, Kleinstern G, Spectre G, Da'as N, Ziv E, Kalish Y. Thromboembolic events following Splenectomy: risk factors, prevention, management and outcomes. World J Surg. 2018;42(3):675–681. doi: 10.1007/s00268-017-4185-2. [DOI] [PubMed] [Google Scholar]
- 4.Goel R, Fleischman AN, Tan T, Sterbis E, Huang R, Higuera C, Parvizi J, Rothman RH. Venous thromboembolic prophylaxis after simultaneous bilateral total knee arthroplasty: aspirin versus warfarin. Bone Joint J. 2018;100-b(1 Supple A):68–75. doi: 10.1302/0301-620X.100B1.BJJ-2017-0587.R1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Hoefnagel D, Kwee LE, van Putten EH, Kros JM, Dirven CM, Dammers R. The incidence of postoperative thromboembolic complications following surgical resection of intracranial meningioma. A retrospective study of a large single center patient cohort. Clin Neurol Neurosurg. 2014;123:150–154. doi: 10.1016/j.clineuro.2014.06.001. [DOI] [PubMed] [Google Scholar]
- 6.Mantziari S, Gronnier C, Pasquer A, Gagniere J, Thereaux J, Demartines N, Schafer M, Mariette C. Incidence and risk factors related to symptomatic venous thromboembolic events after Esophagectomy for Cancer. Ann Thorac Surg. 2016;102(3):979–984. doi: 10.1016/j.athoracsur.2016.03.093. [DOI] [PubMed] [Google Scholar]
- 7.Chen RX, Wang HZ, Dong J, Ren H, Chen XJ, Xu JX, Yang Y, Wang GD. Pulmonary embolism in non-brain tumor patients after surgery-a retrospective study in China. World J Surg Oncol. 2017;15(1):22. doi: 10.1186/s12957-016-1074-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Li YP, Shen L, Huang W, Hu XF, Xie D, Yang J, Song X, Zhao YF, Zhou CJ, Jiang GN. Prevalence and risk factors of acute pulmonary embolism in patients with lung Cancer surgery. Semin Thromb Hemost. 2018;44(4):334–340. doi: 10.1055/s-0037-1612625. [DOI] [PubMed] [Google Scholar]
- 9.Jia J, Xue SM, Xu N. Efficacy of rivaroxaban for pulmonary embolism. Medicine. 2019;98(16):e15224. doi: 10.1097/MD.0000000000015224. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Branchford BR, Carpenter SL. The role of inflammation in venous thromboembolism. Front Pediatr. 2018;6:142. doi: 10.3389/fped.2018.00142. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Jurin I, Trkulja V, Ajduk M, Letilovic T, Hadzibegovic I. Red cell distribution width in acute pulmonary embolism patients: a simple aid for improvement of the 30-day mortality risk stratification based on the pulmonary embolism severity index. Heart Lung. 2019;48(5):436–45. [DOI] [PubMed]
- 12.Ertem AG, Yayla C, Acar B, Kirbas O, Unal S, Uzel Sener M, Akboga MK, Efe TH, Sivri S, Sen F, et al. Relation between lymphocyte to monocyte ratio and short-term mortality in patients with acute pulmonary embolism. Clin Respir J. 2018;12(2):580–586. doi: 10.1111/crj.12565. [DOI] [PubMed] [Google Scholar]
- 13.Soylu K, Gedikli O, Eksi A, Avcioglu Y, Soylu AI, Yuksel S, Gulel O, Yilmaz O. Neutrophil-to-lymphocyte ratio for the assessment of hospital mortality in patients with acute pulmonary embolism. Arch Med Sci. 2016;12(1):95–100. doi: 10.5114/aoms.2016.57585. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Araz O, Yilmazel Ucar E, Yalcin A, Kelercioglu N, Meral M, Gorguner AM, Akgun M. Predictive value of serum Hs-CRP levels for outcomes of pulmonary embolism. Clin Respir J. 2016;10(2):163–167. doi: 10.1111/crj.12196. [DOI] [PubMed] [Google Scholar]
- 15.Hayıroğlu Mİ, Keskin M, Keskin T, Uzun AO, Altay S, Kaya A, Öz A, Çinier G, Güvenç TS, Kozan Ö. A novel independent survival predictor in pulmonary embolism: prognostic nutritional index. Clin Appl Thromb Hemost. 2018;24(4):633–639. doi: 10.1177/1076029617703482. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Hoskin S, Chow V, Kritharides L, Ng ACC. Incidence and Impact of Hypoalbuminaemia on Outcomes Following Acute Pulmonary Embolism. Heart Lung Circ. 2019;29(2):280–7. [DOI] [PubMed]
- 17.Zamorano JL, Achenbach S, Baumgartner H, Bax JJ, Bueno H, Dean V, Deaton C, Erol Ç, Fagard R, Ferrari R. 2014 ESC guidelines on the diagnosis and management of acute pulmonary embolismThe task force for the diagnosis and Management of Acute Pulmonary Embolism of the European Society of Cardiology (ESC)endorsed by the European Respiratory Society (ERS) Eur Heart J. 2014;21(16):1301–1336. [Google Scholar]
- 18.Comfere TB, Sprung J, Case KA, Dye PT, Johnson JL, Hall BA, Schroeder DR, Hanson AC, Marienau ME, Warner DO. Predictors of mortality following symptomatic pulmonary embolism in patients undergoing noncardiac surgery. Can J Anesth. 2007;54(8):634–641. doi: 10.1007/BF03022957. [DOI] [PubMed] [Google Scholar]
- 19.Ma Y, Mao Y, He X, Sun Y, Huang S, Qiu J. The values of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio in predicting 30day mortality in patients with acute pulmonary embolism. BMC Cardiovasc Disord. 2016;16(1):1–6. doi: 10.1186/s12872-015-0179-x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Akgüllü Ç, Ömürlü İK, Eryılmaz U, Avcil M, Dağtekin E, Akdeniz M, Güngör H, Zencir C. Predictors of early death in patients with acute pulmonary embolism. Am J Emerg Med. 2015;33(2):214–221. doi: 10.1016/j.ajem.2014.11.022. [DOI] [PubMed] [Google Scholar]
- 21.Yao CY, Liu XL, Tang Z. Prognostic role of neutrophil–lymphocyte ratio and platelet–lymphocyte ratio for hospital mortality in patients with AECOPD. Int J Chron Obstruct Pulmon Dis. 2017;12:2285–2290. doi: 10.2147/COPD.S141760. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Karakoyun S, Gursoy MO, Akgun T, Ocal L, Kalcik M, Yesin M, Erdogan E, Kulahcioglu S, Bakal RB, Koksal C, et al. Neutrophil-lymphocyte ratio may predict in-hospital mortality in patients with acute type a aortic dissection. Herz. 2015;40(4):716–721. doi: 10.1007/s00059-014-4121-2. [DOI] [PubMed] [Google Scholar]
- 23.Lai FL, Jun WY, Jin NC, He CY, Xia SH. Neutrophil-lymphocyte ratio is associated with all-cause mortality among critically ill patients with acute kidney injury. Clinica Chimica Acta. 2019;490(NA*):207–13. 10.1016/j.cca.2018.09.014. [DOI] [PubMed]
- 24.Park JS, Seo KW, Choi BJ, Choi SY, Yoon MH, Hwang GS, Tahk SJ, Shin JH. Importance of prognostic value of neutrophil to lymphocyte ratio in patients with ST-elevation myocardial infarction. Medicine. 2018;97(48):e13471. doi: 10.1097/MD.0000000000013471. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25.Fei W, Li W, Jiang TT, Xia JJ, Feng X, Shen LJ, Kang WH, Yong D, Mei LX, Ju XF. Neutrophil-to-lymphocyte ratio is an independent predictor of 30-day mortality of Intracerebral hemorrhage patients: a validation cohort study. Neurotox Res. 2018:1–6. [DOI] [PMC free article] [PubMed]
- 26.Wang F, Xu F, Quan Y, Wang L, Xia JJ, Jiang TT, Shen LJ, Kang WH, Ding Y, Mei LX. Early increase of neutrophil-to-lymphocyte ratio predicts 30-day mortality in patients with spontaneous intracerebral hemorrhage. Cns Neurosci Ther. 2018;25(1):30–35. doi: 10.1111/cns.12977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Arbel Y, Shacham Y, Ziv-Baran T, Perl ML, Finkelstein A, Halkin A, Revivo M, Milwidsky A, Berliner S, Herz I. Higher neutrophil/lymphocyte ratio is related to lower ejection fraction and higher Long-term all-cause mortality in ST-elevation myocardial infarction patients. Can J Cardiol. 2014;30(10):1177–1182. doi: 10.1016/j.cjca.2014.05.010. [DOI] [PubMed] [Google Scholar]
- 28.Azab B, Shah N, Radbel J, Tan P, Bhatt V, Vonfrolio S, Habeshy A, Picon A, Bloom S. Pretreatment neutrophil/lymphocyte ratio is superior to platelet/lymphocyte ratio as a predictor of long-term mortality in breast cancer patients. Med Oncol. 2013;30(1):432. doi: 10.1007/s12032-012-0432-4. [DOI] [PubMed] [Google Scholar]
- 29.Zhou M, Li L, Wang X, Wang C, Wang D. Neutrophil-to-lymphocyte ratio and platelet count predict Long-term outcome of stage IIIC epithelial ovarian Cancer. Cell Physiol Biochem. 2018;46(1):178–186. doi: 10.1159/000488420. [DOI] [PubMed] [Google Scholar]
- 30.Long AT, Kenne E, Jung R, Fuchs TA, Renne T. Contact system revisited: an interface between inflammation, coagulation, and innate immunity. J Thromb Haemost. 2016;14(3):427–437. doi: 10.1111/jth.13235. [DOI] [PubMed] [Google Scholar]
- 31.van Montfoort ML, Meijers JC. Recent insights into the role of the contact pathway in thrombo-inflammatory disorders. Hematol Am Soc Hematol Educ Program. 2014;2014(1):60–65. doi: 10.1182/asheducation-2014.1.60. [DOI] [PubMed] [Google Scholar]
- 32.Wu Y. Contact pathway of coagulation and inflammation. Thromb J. 2015;13:17. doi: 10.1186/s12959-015-0048-y. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 33.Fanali G, di Masi A, Trezza V, Marino M, Fasano M, Ascenzi P. Human serum albumin: from bench to bedside. Mol Asp Med. 2012;33(3):209–290. doi: 10.1016/j.mam.2011.12.002. [DOI] [PubMed] [Google Scholar]
- 34.Caraceni P, Domenicali M, Tovoli A, Napoli L, Ricci CS, Tufoni M, Bernardi M. Clinical indications for the albumin use: still a controversial issue. Eur J Intern Med. 2013;24(8):721–728. doi: 10.1016/j.ejim.2013.05.015. [DOI] [PubMed] [Google Scholar]
- 35.Arroyo V, Garcia-Martinez R, Salvatella X. Human serum albumin, systemic inflammation, and cirrhosis. J Hepatol. 2014;61(2):396–407. doi: 10.1016/j.jhep.2014.04.012. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.



