Neutrophil-lymphocyte ratio predicts disease severity and outcome after lower extremity procedures

Development and validation of a major adverse limb events prediction model for peripheral arterial disease with frailty

OBJECTIVE

To investigate the risk factors for major limb adverse events (MALE) in peripheral arterial disease (PAD) combined with frailty and to develop and validate a risk prediction model of MALE.

METHODS

This prospective study was performed in the vascular surgery department of patients in six hospitals in southwest China. Prospective collection of patients with PAD combined with frailty from February 1 to December 20, 2021, with MALE as the primary outcome, and followed for 1 year. The cohort was divided into a development cohort and a validation cohort. In the development cohort, a multivariate risk prediction model was developed to predict MALE using random forests for variable selection and multivariable Cox regression analysis. The model is represented by a visualized nomogram and a web-based calculator. The model performance was tested with the validation cohort and assessed using the C-statistic and calibration plots.

RESULTS

A total of 1179 patients were prospectively enrolled from February 1 to December 20, 2021. Among 816 patients with PAD who were included in the analysis, the median follow-up period for this study was 9 ± 4.07 months, the mean age was 74.64 ± 9.43 years, and 249 (30.5%) were women. Within 1 year, 222 patients (27.2%) developed MALE. Target lesion revascularizations were performed in 99 patients (12.1%), and amputations were performed in 131 patients (16.1%). The mortality rate within the whole cohort was 108 patients (13.2%). After controlling for competing risk events (death), the cumulative risk of developing MALE was not statistically different. Prealbumin (hazard ratio [HR], 0.6; 95% confidence interval [CI], 0.41-0.89; P = .010), percutaneous coronary intervention (HR, 2.31; 95% CI, 1.26-4.21; P = .006), Rutherford classification (HR, 1.77; 95% CI, 1.36-2.31; P < .001), white blood cell (HR, 1.85; 95% CI, 1.20-2.87; P = .005), high altitude area (HR, 3.1; 95% CI, 1.43-6.75; P = .004), endovascular treatment (HR, 10.2; 95% CI, 1.44-72.50; P = .020), and length of stay (HR, 1.01; 95% CI, 1.00-1.03; P = .012) were risk factors for MALE. The MALE prediction model had a C-statistic of 0.76 (95% CI, 0.70-0.79). The C-statistic was 0.68 for internal validation and 0.66 for external validation for the MALE prediction model. The MALE prediction model for PAD presented an interactive nomogram and a web-based network calculator.

CONCLUSIONS

In this study, the MALE prediction model has a discriminative ability to predict MALE among patients with PAD in frailty. The MALE model can optimize clinical decision-making for patients with PAD in frailty.

The Relationship between Clinical Frailty Score, CT-Derived Body Composition, Systemic Inflammation, and Survival in Patients with Chronic Limb-Threatening Ischemia

BACKGROUND

Frailty is a chronic condition with complex etiology and impaired functional performance that has been associated with altered body composition and chronic inflammation. Chronic limb-threatening ischemia (CLTI) carries significant morbidity and mortality and is associated with poor quality of life. The present study aims to examine these relationships and their prognostic value in patients with CLTI.

METHODS

Consecutive patients presenting as unscheduled admissions to a single tertiary center with CLTI were included over a 12-month period. Frailty was diagnosed using the Clinical Frailty Scale (CFS). Body composition was assessed using computerised tomography (CT) at the L3 vertebral level (CT-BC) to generate visceral and subcutaneous fat indices, skeletal muscle index, and skeletal muscle density. Skeletal muscle index and skeletal muscle density were combined to form the CT-sarcopenia score (CT-SS). Systemic inflammation was assessed by the modified Glasgow prognostic score (mGPS). The primary outcome was overall mortality.

RESULTS

There were 190 patients included with a median (interquartile range) follow-up of 22 (6) months (range 15-32 months) and 79 deaths during the follow-up period. One hundred patients (53%) had a CFS >4. CFS >4 (hazard ratio [HR] 2.14, 95% confidence interval [CI] 1.25-3.66, P < 0.01), CT-SS (HR 1.47, 95% CI 1.03-2.09, P < 0.05), and mGPS (HR 1.54, 95% CI 1.11-2.13, P < 0.01) were independently associated with increased mortality. CT-SS (odds ratio 1.88, 95% CI 1.09-3.24, P < 0.01) was independently associated with CFS >4. Patients with CT-SS 0 and CFS ≤4 had 90% (standard error [SE] 5%) 1-year survival, compared with 35% (SE 9%) in patients with CT-SS 2 and CFS >4 (P < 0.001). Patients with mGPS 0 and CFS ≤4 had 94% (SE 4%) 1-year survival compared with 44% (SE 6%) in the mGPS 2 and CFS >4 subgroup (P < 0.001).

CONCLUSIONS

Frailty assessed by CFS was associated with CT-BC. CFS, CT-SS, and mGPS were associated with poorer survival in patients presenting as unscheduled admissions with CLTI. CT-SS and mGPS may contribute to part of frailty and prognostic assessment in this patient cohort.

A systematic review of the neutrophil to lymphocyte and platelet to lymphocyte ratios in patients with lower extremity arterial disease

Lower extremity arterial disease (LEAD) is caused by atherosclerotic plaque in the arterial supply to the lower limbs. The neutrophil to lymphocyte and platelet to lymphocyte ratios (NLR, PLR) are established markers of systemic inflammation which are related to inferior outcomes in multiple clinical conditions, though remain poorly described in patients with LEAD. This review was carried out in accordance with PRISMA guidelines. The MEDLINE database was interrogated for relevant studies. Primary outcome was the prognostic effect of NLR and PLR on clinical outcomes following treatment, and secondary outcomes were the prognostic effect of NLR and PLR on disease severity and technical success following revascularisation. There were 34 studies included in the final review reporting outcomes on a total of 19870 patients. NLR was investigated in 21 studies, PLR was investigated in two studies, and both NLR & PLR were investigated in 11 studies. Relating to increased levels of systemic inflammation, 20 studies (100%) reported inferior clinical outcomes, 13 (92.9%) studies reported increased disease severity, and seven (87.5%) studies reported inferior technical results from revascularisation. The studies included in this review support the role of elevated NLR and PLR as key components influencing the clinical outcomes, severity, and success of treatment in patients with LEAD. The use of these easily accessible, cost effective and routinely available markers is supported by the present review.

Risk factor analysis for diabetic foot ulcer-related amputation including Controlling Nutritional Status score and neutrophil-to-lymphocyte ratio

Diabetic foot ulcer often leads to amputation, and both nutritional status and immune function have been associated with this process. We aimed to investigate the risk factors of diabetic ulcer-related amputation including the Controlling Nutritional Status score and neutrophil-to-lymphocyte ratio biomarker. We evaluated data from hospital in patients with diabetic foot ulcer, performing univariate and multivariate analyses to screen for high-risk factors and Kaplan-Meier analysis to correlate high-risk factors with amputation-free survival. Overall, 389 patients underwent 247 amputations over the follow-up period. After correction to relevant variables, we identified five independent risk factors for diabetic ulcer-related amputation: ulcer severity, ulcer site, peripheral arterial disease, neutrophil-to-lymphocyte ratio and nutritional status. Amputation-free survival was lower for the moderate-to-severe versus mild cases, for the plantar forefoot versus hindfoot location, for the concomitant peripheral artery disease versus without and in the high versus low neutrophil-to-lymphocyte ratio (all p < 0.01). The results showed that ulcer severity (p < 0.01), ulcer site (p < 0.01), peripheral artery disease (p < 0.01), neutrophil-to-lymphocyte ratio (p < 0.01) and Controlling Nutritional Status score (p < 0.05) were independent risk factors for amputation in diabetic foot ulcer patients and have predictive values for diabetic foot ulcer progression to amputation.

Comparison of complete multi-level vs. iliac-only revascularization for concomitant iliac and superficial femoral artery occlusive disease

Objective

The aim of this study is to compare the efficacy and safety of complete multi-level vs. iliac-only revascularization for the treatment of concomitant iliac and superficial femoral artery (SFA) occlusive disease.

Methods

A total of 139 consecutive adult patients with severe stenosis and occlusive iliac and SFA disease with Rutherford categories 2-5 underwent multi-level (n = 71) and iliac-only (n = 68) revascularization at the Department of Intervention Vascular Surgery, Peking University Third Hospital, and Aerospace Center Hospital, between March 2015 and June 2017. Improvement in Rutherford class, perioperative major adverse events, the length of stay, survival rate, and limb salvage rate were assessed. The neutrophil-lymphocyte ratio and platelet-lymphocyte ratio were compared between the two groups.

Results

At 48 months, improvement in the Rutherford category was observed in the two groups with no significant difference (P = 0.809). Additionally, the two groups were similar concerning the primary patency (84.0% vs. 79.1%, P = 0.717) and limb salvage rate (93.1% vs. 91.3%, P = 0.781). A higher proportion of the perioperative major adverse events (33.8% vs. 27.9%, P = 0.455), the all-cause mortality (11.3% vs. 8.8%, P = 0.632), and the average length of hospital stay [7.0 (6.0, 11.0) vs. 7.0 (5.0, 8.0), P = 0.037] were seen in the multi-level group compared with the iliac-only group.

Conclusion

For concomitant iliac and superficial femoral artery occlusive disease, iliac-only revascularization has favorable efficacy and safety outcomes compared with complete multi-level revascularization in selected patients with patent profunda femoris artery and at least one healthy outflow tract of the infrapopliteal artery.

The Role of Neutrophils in Lower Limb Peripheral Artery Disease: State of the Art and Future Perspectives

In recent years, increasing attention has been paid to the role of neutrophils in cardiovascular (CV) disease (CVD) with evidence supporting their role in the initiation, progression, and rupture of atherosclerotic plaque. Although these cells have long been considered as terminally differentiated cells with a relatively limited spectrum of action, recent research has revealed intriguing novel cellular functions, including neutrophil extracellular trap (NET) generation and inflammasome activation, which have been linked to several human diseases, including CVD. While most research to date has focused on the role of neutrophils in coronary artery and cerebrovascular diseases, much less information is available on lower limb peripheral artery disease (PAD). PAD is a widespread condition associated with great morbidity and mortality, though physician and patient awareness of the disease remains low. To date, several studies have produced some evidence on the role of certain biomarkers of neutrophil activation in this clinical setting. However, the etiopathogenetic role of neutrophils, and in particular of some of the newly discovered mechanisms, has yet to be fully elucidated. In the future, complementary assessment of neutrophil activity should improve CV risk stratification and provide personalized treatments to patients with PAD. This review aims to summarize the basic principles and recent advances in the understanding of neutrophil biology, current knowledge about the role of neutrophils in atherosclerosis, as well as available evidence on their role of PAD.

ERICVA Risk Scale simplified as a predictor of amputation in critical limb ischemia

OBJECTIVE

Demonstrate that simplified ERICVA (Valladolid Critical Limb Ischaemia Risk Scale) is useful in predicting amputation in chronic limb-threatening ischemia (CLI) after one year of revascularization.

METHODS

A retrospective cohort study was performed. We analyzed the medical records of 93 patients over the age of 35 with the diagnosis of CLI who were treated in the Department of Internal Medicine, Orthopedics or in the Cardiovascular Surgery Unit of the Víctor Lazarte Echegaray Hospital and the High Complexity Virgen de La Puerta Hospital during the period 2015-2018. The simplified ERICVA score was determined in patients before surgical and endovascular revascularization. We included 31 patients who scored 2 or more points in the exposed group and 62 patients who scored less than 2 points in the group not exposed to amputation risk. The collected data was analyzed with the statistical program SPSS where the Relative Risk and significance was obtained with Pearson's Chi-square. The multivariate analysis was also carried out in order to obtain the adjusted relative risk.

RESULTS

It was identified that the simplified ERICVA score greater than or equal to 2 points was more frequent in those who underwent amputation (90.3%) compared to patients who did not undergo amputation (4.8%), increasing the risk of amputation in those patients with CLI who underwent revascularization (RR: 18.67, P<0.001). It was also possible to identify that within the group of patients that showed a high risk of amputation according to the ERICVA scale, they had a higher risk of major amputation (RR: 9.32, P<0.001) as opposed to the risk of minor amputation (RR: 1, 89, P=0.193). Among the items of the simplified ERICVA scale, the preoperative neutrophil-lymphocyte ratio and hematocrit were significantly higher in the group of amputated patients (P<0.001). In addition, it was possible to identify that the score greater than or equal to 2 was independently associated with the risk of amputation in patients revascularized with CLI (RR: 13.5, P<0.001).

CONCLUSION

In our patient population, the simplified ERICVA scale is useful in predicting major and minor amputation in critical limb ischemia after revascularization. The present data showed that the patients who had a simplified ERICVA score greater than or equal to 2 had a higher risk of major amputation compared to the risk of minor amputation. However, it is important to highlight that the impact on the prediction of minor amputation is greater because in some circumstances major amputation can appear as a complication of CLI.

A Novel Marker Indicating Restenosis in Superficial Femoral Artery: C Reactive Protein to Albumin Ratio

AIM

In this study, we aimed to investigate the prognostic value of CAR for predicting restenosis in SFA lesions and its association with subsequent clinical outcomes in patients undergoing endovascular intervention.

METHODS

The records of 685 consecutive patients who underwent endovascular intervention due to symptomatic peripheral artery disease were analyzed. Patients were divided into 2 groups based on the CAR values. For each group, technical aspects of procedures and subsequent clinical outcomes were analyzed.

RESULTS

According to our study, patients with high CAR values had higher rates of restenosis (30.2% vs 10.3%, p<0.05) and mortality (31.3% vs 12.9%, p<0.05). The rate of lower extremity amputations was also significantly higher in patients with high CAR values compared to those with low CAR values (9.1% vs 3%, p<0.05). With respect to ROC curves of inflammatory markers, the area under the curve (AUC) value of CAR was statistically significant (AUC: 0.659; 95% CI: 0.611-0.706; p<0.01).

CONCLUSION

Our data showed that CAR is an independent predictor of restenosis and poor clinical outcomes in patients undergoing endovascular intervention.

Association of neutrophils, lymphocytes, and neutrophil-lymphocyte ratio to overall mortality after endovascular abdominal aortic aneurysm repair

BACKGROUND

The purpose of this study was to determine the predictive ability of neutrophilia, lymphocytopenia, and neutrophil-lymphocyte ratio (NLR) for overall mortality after EVAR for AAA.

METHODS

Data on patients with AAA treated by EVAR between March 2012 and December 2016 were obtained from a prospectively maintained EVAR database at Tokyo Medical University Hospital. The NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. A cut-off value of total WBC count, neutrophil count, lymphocyte count, and NLR was determined according to a receiver operating characteristic (ROC) curve. Univariate and multivariate analyses were performed using the Cox proportional hazard analyses to account for the time at risk.

RESULTS

178 patients were included in this study after selection based on the exclusion criteria. The subjects consisted of 150 men and 28 women with a mean age of 77.5 years (range, 51-89 years). A ROC curve analysis determined the optimal cut-off values of preoperative total WBC, neutrophils, lymphocytes, and NLR for predicting overall mortality with 7,050 /μL, 4,012 /μL, 1,312 /μL, and 3.19, respectively. On univariate analysis and multivariate analyses, octogenarian, obesity, COPD, active cancer, and lymphocytopenia or NLR were detected as independent predictors for overall mortality.

CONCLUSIONS

Specific leukocyte populations, such as lymphocyte count and NLR, are useful biomarkers to predict overall mortality in patients undergoing EVAR for AAA, suggesting that WBC count and its subsets, which are easy to perform a test, may be used to stratify patients at risk for poor prognosis following EVAR.

Preoperative HbA1c and Outcomes Following Lower Extremity Vascular Procedures

OBJECTIVES

Limited data exist evaluating pre-operative hemoglobin A1c (HbA1c) in patients undergoing vascular procedures for peripheral arterial disease (PAD). This study evaluated the relationship of preoperative HbA1c on outcomes after open and endovascular lower extremity (LE) vascular procedures for PAD.

METHODS

We selected patients with PAD admitted for elective LE procedures between September 2008 and December 2015 from the Cerner Health Facts® database using ICD-9-CM diagnosis and procedure codes. Bivariable analysis and multivariable logistic models examined the association of patient characteristics, procedure type, and preoperative HbA1c (normal < 6.5%, high ≥ 6.5%) with postsurgical outcomes that included infection, renal failure, respiratory or cardiac complications, length of stay (LOS), in-hospital mortality, and readmission.

RESULTS

Of 4,087 patients who underwent a LE vascular procedure for PAD, 2,462 (60.2%) had a preoperative HbA1c recorded. The cohort was mostly male (60%), white (73%), and underwent endovascular intervention (77%). Patients with high HbA1c levels were more likely of black race (p < .02) and had significantly higher comorbidities (p < .0001). Elevated HbA1c was associated with diabetes (p < .0001) and cellulitis (p = .05) on unadjusted analysis. Multivariable logistic regression (adjusting for patient, hospital, comorbidity and procedural characteristics) revealed that elevated HbA1c was significantly associated with 30-day readmission (OR = 1.06, 95% CI = 1.00-1.12), but was not associated with the other outcomes. An independent diagnosis of diabetes was not predictive of complications or readmission.

CONCLUSIONS

Historic glucose control, as evidenced by a high preoperative HbA1c level, is not associated with adverse outcome, other than readmission, in patients undergoing LE procedures for PAD. Given the known association of high perioperative glucose levels with poor outcome following vascular procedures, this is suggestive of a more important effect of perioperative, as opposed to chronic, glucose control upon outcome. Thus, we suggest focusing efforts on creating standardized goal-directed guidelines for glucose control in the perioperative period for LE vascular procedures to potentially mitigate complications.

Possible indicators of amputation and insufficient perfusion after heat press injury: A retrospective study

INTRODUCTION

Amputation outcome after heat press injury is associated with insufficient perfusion. We aimed to determine other risk factors for heat press injury and mechanisms of insufficient perfusion associated with amputation.

METHODS

We retrospectively classified 120 inpatients into the emergency and clinic groups, with arrival time before and after 48 h of injury, respectively. We performed propensity score-match to identify significant variables and combine them with those previously identified. Patients with or without amputation were categorized in different subgroups according to arrival time and perfusion with receiver-operator-characteristic (ROC) curves.

RESULTS

In the emergently insufficient perfusion subgroup, red blood cell distribution width of standard deviation (RDW-SD) was statistically different between patients without and with amputation (cutoff = 43 fL; specificity = 0.909). In the urgent group, neutrophil-lymphocyte-ratio (NLR) and relative lymphocyte count (L%) showed no association with perfusion, but was associated with amputation (NLR cutoff value = 3.12; sensitivity = 0.846). Differential leukocytes and related ratios (both groups), D-dimer (emergency group), and creatine kinase (CK) (clinic group) were also associated with insufficient perfusion.

CONCLUSION

The study showed some correlations. Inflammation variables, D-dimer, and CK were associated with amputation and perfusion after heat press injury. Several factors were associated with amputation, including RDW-SD increase in insufficiently perfused patients within 48 h of injury, and NLR increase and L% decrease in patients after 48 h post-injury.

Elevated Neutrophil to Lymphocyte Ratio is Associated with Worse Outcomes after Carotid Endarterectomy in Asymptomatic Patients

OBJECTIVE

Management of carotid artery stenosis (CAS) remains controversial and proper patient selection critical. Elevated neutrophil to lymphocyte ratio (NLR) has been associated with poor outcomes after vascular procedures. The effect of NLR on outcomes after carotid endarterectomy (CEA) in asymptomatic and symptomatic patients is assessed.

MATERIALS AND METHODS

A retrospective review was conducted of all patients between 2010 and 2018 with carotid stenosis >70% as defined by CREST 2 criteria. A total of 922 patients were identified, of whom 806 were treated with CEA and 116 non-operatively with best medical therapy (BMT). Of patients undergoing CEA, 401 patients (290 asymptomatic [aCEA], 111 symptomatic [sCEA]) also had an available NLR calculated from a complete blood count with differential. All patients treated with BMT were asymptomatic and had a baseline NLR available. Kaplan-Meier analysis assessed composite ipsilateral stroke or death over 3 years.

RESULTS

In sCEA group, the 3-year composite stroke/death rates did not differ between NLR < 3.0 (22.9%) vs NLR > 3.0 (38.1%) (P=.10). In aCEA group, patients with a baseline NLR >3.0 had an increased risk of 3-year stroke/death (42.6%) compared to both those with NLR <3.0 (9.3%, P<.0001) and those treated with BMT (23.6%, P=.003). In patients with NLR <3.0, aCEA showed a superior benefit over BMT with regard to stroke or death (9.3% vs. 26.2%, P=.02). However, in patients with NLR >3.0, there was no longer a benefit to prophylactic CEA compared to BMT (42.6% vs. 22.2%, P=.05). Multivariable analysis identified NLR >3.0 (HR, 3.23; 95% CI, 1.93-5.42; P<.001) and congestive heart failure (HR, 2.18; 95% CI, 1.33-3.58; P=.002) as independent risk factors for stroke/death in patients with asymptomatic carotid artery stenosis.

CONCLUSIONS

NLR >3.0 is associated with an increased risk of late stroke/death after prophylactic CEA for asymptomatic carotid artery stenosis, with benefits not superior to BMT. NLR may be used to help with selecting asymptomatic patients for CEA. The effect of NLR and outcomes in symptomatic patients requires further study. Better understanding of the mechanism(s) for NLR elevation and medical intervention strategies are needed to modulate outcome risk in these patients.

In-stent restenosis and stent compression following stenting for chronic iliofemoral venous obstruction

OBJECTIVE

In-stent restenosis (ISR) and stent compression (SC) are problems encountered after stenting for chronic iliofemoral venous obstruction that are responsible for a majority of reinterventions. However, characteristics of ISR and SC, in addition to outcomes after reintervention, have not been explored in detail and represent the focus of this study.

METHODS

A retrospective analysis of contemporaneously entered electronic medical record data on 578 limbs/patients with initial unilateral iliofemoral venous stents placed from 2014 to 2018 was performed. ISR was estimated from stent and flow channel diameters measured using duplex ultrasound. SC was estimated from rated stent diameter and actual stent diameter on duplex ultrasound. Characteristics evaluated included onset of ISR/SC after stent placement and progression over time. Analysis was performed to evaluate risk factors for the development of ISR and SC. Outcomes after reintervention for ISR/SC were also appraised.

RESULTS

A total of 578 limbs underwent stenting for stenotic lesions (nonthrombotic iliac vein lesion/post-thrombotic syndrome). ISR was noted in 27% of limbs on post-intervention day 1. The prevalence of ISR increased to 74% by 3 months and stabilized thereafter. SC was noted in 80% of limbs on day 1 and plateaued. Of the variables evaluated as potential risk factors for ISR, intravascular ultrasound determined that stent inflow luminal area and shear rate were found to be significant. For SC, asymmetric stent sizing was a significant risk factor. Over a median follow-up of 24 months, 95 of 578 (16.4%) limbs underwent reintervention for ISR, SC, or a combination. The median time to reintervention was 11 months. There was no statistically significant difference in the degree of ISR/SC among patients who underwent reintervention vs those who did not (P > .05). However, there was a statistically significant difference in the grade of swelling (P = .006) and visual analog scale pain scores (P < .0001) between those who underwent reintervention and those who did not. Primary, primary assisted, and secondary patencies at 60 months were 70%, 98%, and 84% after reintervention for ISR and 70%, 99%, and 84% for SC, respectively.

CONCLUSIONS

Although ISR and SC are both common after stenting for chronic iliofemoral venous obstruction, neither are relentlessly progressive. Indication for reintervention must be a recurrence of symptoms with impairment of quality of life and not the percentage of ISR or degree of SC. After reintervention good outcomes can be expected both in terms of clinical improvement and stent patency. Further study of the impact of shear rate on stent flow is required to help reduce the incidence of ISR.

Elevated neutrophil to lymphocyte ratio is associated with decreased amputation-free survival after femoropopliteal percutaneous revascularization

BACKGROUND

An elevated neutrophil-lymphocyte ratio (NLR) is a biomarker associated with adverse outcomes after cardiovascular surgery. This study evaluates the association of preoperative NLR with clinical outcomes after peripheral vascular intervention (PVI) of the femoropopliteal segments.

METHODS

A retrospective review identified 488 patients who underwent percutaneous interventions of femoropopliteal arteries between 2011 and 2018 and had a pre-procedural complete blood count with differential with normal white blood cell count within 30 days prior to intervention. Amputation-free survival (AFS), survival, and freedom from major amputation were assessed using Kaplan-Meier methods. Cohorts of patients with NLR <3 (Low), 3-4 (Mid), and >4 (High) were compared using univariate and multivariable statistical models. In these analyses NLR was analyzed as a continuous variable to correlate with clinical outcomes.

RESULTS

Mean age was 71.7 ± 12.8 years and males constituted 55.5%. The majority of patients presented with chronic limb threatening ischemia (CLTI, 78.5%). Increasing NLR was correlated with increasing rates of comorbidities, except for smoking history. The 30-day mortality rates increased with increasing NLR: 1.4%, 4.3%, and 7.0% for Low (<3), Mid (3-4) and High (>4) NLR groups, respectively (P =.005). Patients with a lower pre-operative NLR achieved significantly greater amputation-free survival at 4-year follow-up: low NLR, 65.5%; mid NLR, 37.5%; and high NLR, 17.6% (P <.0001). By multivariable analysis, increasing NLR, advanced age, CLTI, and dialysis-dependent renal failure reduced AFS.

CONCLUSIONS

Elevated NLR is an independent predictor of decreased AFS following percutaneous interventions of femoropopliteal segments. Further research on identification and modulation of risk factors for high NLR are warranted.

Neutrophil-to-lymphocyte ratio associated with an increased risk of mortality in patients with critical limb ischemia

Purpose

Association of the neutrophil-to-lymphocyte ratio (NLR) with mortality has not been comprehensively explored in critical limb ischemia (CLI) patients. We investigated the association between the NLR and clinical outcomes in CLI.

Materials and methods

We retrospectively enrolled consecutive CLI patients between 1/1/2013 and 12/31/2018. Receiver operating characteristic curve analysis determined NLR cutoffs for 1-year in-hospital, all-cause and cardiac-related mortality; major adverse cardiovascular events (MACEs); and major adverse limb events (MALEs).

Results

Among 195 patients (age, 74.0 years, SD: 11.5; 51.8% male; body mass index, 23.4 kg/m², SD: 4.2), 14.4% exhibited acute limb ischemia. After 1 year, patients with NLR>8 had higher in-hospital mortality (21.1% vs. 3.6%, P<0.001), all-cause mortality (54.4% vs. 13.8%, P<0.001), cardiac-related mortality (28.1% vs. 6.5%, P<0.001), MACE (29.8% vs. 13.0%, P = 0.008), and MALE (28.1% vs. 13.0%, P = 0.021) rates than those with NLR<8. In multivariate logistic regression, NLR≥8 was significantly associated with all-cause (P<0.001) and cardiac-related (adjusted HR: 5.286, 95% CI: 2.075–13.47, P<0.001) mortality, and NLR≥6 was significantly associated with MALEs (adjusted HR: 2.804, 95% CI: 1.292–6.088, P = 0.009). Each increase in the NLR was associated with increases in all-cause (adjusted HR: 1.028, 95% CI: 1.008–1.049, P = 0.007) and cardiac-related (adjusted HR:1.027, 95% CI: 0.998–1.057, P = 0.073) mortality but not in-hospital mortality or MACEs.

Conclusion

CLI patients with high NLRs had significantly higher risks of 1-year all-cause and cardiac-related mortality and MALEs. The NLR can be used for prognostic prediction in these patients.

The Role of Circulating Biomarkers in Peripheral Arterial Disease

Peripheral arterial disease (PAD) of the lower extremities is a chronic illness predominantly of atherosclerotic aetiology, associated to traditional cardiovascular (CV) risk factors. It is one of the most prevalent CV conditions worldwide in subjects >65 years, estimated to increase greatly with the aging of the population, becoming a severe socioeconomic problem in the future. The narrowing and thrombotic occlusion of the lower limb arteries impairs the walking function as the disease progresses, increasing the risk of CV events (myocardial infarction and stroke), amputation and death. Despite its poor prognosis, PAD patients are scarcely identified until the disease is advanced, highlighting the need for reliable biomarkers for PAD patient stratification, that might also contribute to define more personalized medical treatments. In this review, we will discuss the usefulness of inflammatory molecules, matrix metalloproteinases (MMPs), and cardiac damage markers, as well as novel components of the liquid biopsy, extracellular vesicles (EVs), and non-coding RNAs for lower limb PAD identification, stratification, and outcome assessment. We will also explore the potential of machine learning methods to build prediction models to refine PAD assessment. In this line, the usefulness of multimarker approaches to evaluate this complex multifactorial disease will be also discussed.

Clinical application values of neutrophil-to-lymphocyte ratio in intracranial aneurysms

Inflammation plays an important role in the pathogenesis and growth of intracranial aneurysms (IAs). We investigated the clinical value of the neutrophil-to-lymphocyte ratio (NLR) as a marker of systemic subclinical inflammation in patients with IAs.

Consecutive patients with IAs who underwent endovascular treatment (EVT) were enrolled in the study. The evaluation indicators were aneurysm size and rupture, a poor outcome at 3 to 6 months, and delayed cerebral ischemia (DCI) during hospitalization.

In total, 532 patients with IAs underwent EVT (mean age, 54.0 years; 62.4% female). Among patients with ruptured IAs, those with a higher NLR had an increased risk of a poor outcome at 3 to 6 months and DCI during hospitalization than those with a lower NLR. A higher NLR was significantly more strongly associated with the size of unruptured aneurysms and aneurysm rupture than a lower NLR. The NLR and C-reactive protein concentration showed similar predictive ability for aneurysm size and treatment prognosis. The NLR was lower at discharge than admission for patients with ruptured IAs and DCI.

An elevated NLR was significantly associated with the size of unruptured IAs, an increased risk of a poor outcome, and DCI in patients with ruptured IAs.

Neutrophil-lymphocyte ratio as a link between complex pedal ulcers and poor clinical results after infrainguinal surgical revascularization

BACKGROUND

Our aim was to evaluate the influence of preoperative neutrophil-lymphocyte ratio (NLR) on patency and clinical results after infrainguinal surgical revascularization for chronic limb ischemia.

METHODS

Retrospective analysis of 150 infrainguinal autologous bypasses performed to infragenicular popliteal artery or tibial vessels in 140 (93%) patients with chronic limb-threatening ischemia (CLTI) and in 10 (7%) with disabling claudication. NLR was calculated using blood samples obtained 24 hours preoperatively. The cohort was stratified into 2 groups according to interquartile ranges of NLR: "ELEVATED-NLR" (Quartile 4 N.=37) and "LOW-NLR" (Quartile 1-2-3 N.=113). Reperfused ulcers were described using the WIfI classification. Patency, freedom from MALE and amputation-free survival at 24 months were calculated using the Kaplan-Meier method. Univariate comparisons between NLR groups were performed using the Log-Rank test. Statistical differences on univariate analysis were adjusted in a multivariate model (Cox regression).

RESULTS

NLR values were similar between CLTI and claudication. Ischemic ulcers were more frequent, (83.4% vs. 59.3% P<0.01), more severe (W2-3: 37.8% vs. 22.1% P=0.01) and pedal infection was deeper (fI 2-3: 40.5% vs. 18.6% P=0.003) in "ELEVATED-NLR" group. Severe ischemia (I3) was similar between groups. High NLR values were independent predictors of patency loss (HR: 1.77 CI95% [1.01-3.10] P=0.04), MALE (HR: 2.04 CI95% [1.03-4.04] P=0.04) and worse amputation-free survival (HR:2.10 CI95% [1.06-4.14] P=0.03) rates at 24 months.

CONCLUSIONS

High preoperative NLR values are associated with severe and deep infected ulcers and predicts primary patency loss, higher major adverse limb events and worse amputation-free survival rates on long-term follow-up after infrainguinal surgical revascularization.

Blood Cell Count Biomarkers, Risk, and Outcomes of Ischemia-Related Lower Limb Amputations: Systematic Review

Lower limb amputations due to ischemia represent an important health care and social issue. However, there are currently no specific biomarkers able to predict the risk of amputation and postamputation complications and prognosis. We conducted a systematic review of studies investigating whether blood cell count indexes of systemic inflammation are linked to the risk and the outcome of lower limb amputations due to ischemia. Overall, in 22 studies involving 8832 patients selected for review, several blood cell count indexes, particularly the neutrophil lymphocyte ratio, showed some promise in terms of predicting amputations and general outcomes of conservative and surgical treatments, as well as postamputation complications and prognosis. However, largely due to methodological limitations, further prospective studies are required to establish the clinical utility and applicability of blood cell indexes in the routine management of patients with ischemia-related lower limb amputations.

Prognostic role of neutrophil-to-lymphocyte ratio in aortic disease: a meta-analysis of observational studies

OBJECTIVE

Recent studies have reported that neutrophil-to-lymphocyte ratio (NLR) is associated with cardiovascular disease. The aim of the present study was to investigate the prognostic value of NLR in aortic disease.

METHODS

We systematically searched electronic databases (Cochrane, PubMed, Elsevier, Medline, and Embase) from their inception to March 2020. Observational studies that evaluated the relationship between NLR and aortic disease were eligible for critical appraisal. Data were extracted from applicable articles, risk ratio (RR), weighted mean differences (MD) and 95% confidence intervals (CI) were calculated by RevMan 5.3, and statistical heterogeneity was assessed by the I² statistic.

RESULTS

Fourteen studies enrolling 4066 individuals were included in the meta-analysis. Compared with the control group, NLR was significantly higher in the aortic disease group (MD 3.44, 95%CI: 0.81-6.07, P = 0.01, I² = 99%). The NLR was also significantly higher in non-survivors with aortic disease, compared to the survivors (MD 4.62, 95%CI: 2.75-6.50, P < 0.00001, I² = 60%). Compared with the aortic disease patients with a low NLR, mortality was significantly higher in those with a high NLR (RR 2.63, 95%CI: 1.79-3.86, P < 0.00001, I² = 67%).

CONCLUSION

Based on current evidence, an elevated NLR was associated with aortic disease and in-hospital mortality. Raised NLR also demonstrated a significantly increased the risk of mortality after surgical repair in aortic disease patients. NLR may be a good prognostic biomarker in aortic disease and deserve further research in this area.