The association of neutrophil-to-lymphocyte ratio and delayed cerebral ischemia in patients with aneurysmal subarachnoid hemorrhage: possible involvement of cerebral blood perfusion

Neutrophil lymphocyte ratio (NLR) and systemic immune inflammatory index (SII) for the differential diagnosis of CT-negative mild acute ischemic stroke and transient ischemic attack

Background: A number of acute ischemic stroke (AIS) cases may be misdiagnosed as transient ischemic attack (TIA), due to no infarct on initial computed tomography scan and/or mild deficits upon presentation. Several studies have found that the neutrophil-lymphocyte ratio (NLR) is an accurate differential diagnostic biomarker for AIS versus TIA; however, no study has evaluated the use of the NLR in differentiating CT negative AIS from TIA. Furthermore, the systemic immune-inflammation index (SII) is a relatively novel immune biomarker that has been shown to be positively correlated with AIS severity, poor functional outcomes and mortality. The purpose of this study is to determine if NLR or SII can be used as a diagnostic biomarker for the differential diagnosis of mild AIS with a negative CT upon admission and TIA. Methods: We performed a retrospective medical record review of patients diagnosed with either AIS or TIA. We collected peripheral white blood cell counts within 24 h of symptom onset and calculated the NLR and SII. Logistic regression was utilized to determine if NLR or SII are significant predictors of CT negative mild AIS. Results: CT negative mild AIS patients were 2 times as likely to have an NLR ≥ 2.71 compared to TIA patients, and CT negative mild AIS patients were 2.1 times as likely to have an SII ≥ 595 compared to TIA patients. Conclusion: NLR and SII are easily obtained biomarkers that can be used in early clinical decision making in cases of mild AIS with negative CT scan upon admission.

Sex-Related Differences in Mortality, Delayed Cerebral Ischemia, and Functional Outcomes in Patients with Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

Background/Objective: Sex-related differences among patients with aneurysmal subarachnoid hemorrhage (aSAH) and their potential clinical implications have been insufficiently investigated. To address this knowledge gap, we conduct a comprehensive systematic review and meta-analysis. Methods: Sex-specific differences in patients with aSAH, including mortality, delayed cerebral ischemia (DCI), and functional outcomes were assessed. The functional outcome was dichotomized into favorable or unfavorable based on the modified Rankin Scale (mRS), Glasgow Outcome Scale (GOS), and Glasgow Outcome Scale Extended (GOSE). Results: Overall, 2823 studies were identified in EMBASE, MEDLINE, PubMed, and by manual search on 14 February 2024. After an initial assessment, 74 studies were included in the meta-analysis. In the analysis of mortality, including 18,534 aSAH patients, no statistically significant differences could be detected (risk ratio (RR) 0.99; 95% CI, 0.90-1.09; p = 0.91). In contrast, the risk analysis for DCI, including 23,864 aSAH patients, showed an 11% relative risk reduction in DCI in males versus females (RR, 0.89; 95% CI, 0.81-0.97; p = 0.01). The functional outcome analysis (favorable vs. unfavorable), including 7739 aSAH patients, showed a tendency towards better functional outcomes in men than women; however, this did not reach statistical significance (RR, 1.02; 95% CI, 0.98-1.07; p = 0.34). Conclusions: In conclusion, the available data suggest that sex/gender may play a significant role in the risk of DCI in patients with aSAH, emphasizing the need for sex-specific management strategies.

All Three Supersystems-Nervous, Vascular, and Immune-Contribute to the Cortical Infarcts After Subarachnoid Hemorrhage

The recently published DISCHARGE-1 trial supports the observations of earlier autopsy and neuroimaging studies that almost 70% of all focal brain damage after aneurysmal subarachnoid hemorrhage are anemic infarcts of the cortex, often also affecting the white matter immediately below. The infarcts are not limited by the usual vascular territories. About two-fifths of the ischemic damage occurs within ~ 48 h; the remaining three-fifths are delayed (within ~ 3 weeks). Using neuromonitoring technology in combination with longitudinal neuroimaging, the entire sequence of both early and delayed cortical infarct development after subarachnoid hemorrhage has recently been recorded in patients. Characteristically, cortical infarcts are caused by acute severe vasospastic events, so-called spreading ischemia, triggered by spontaneously occurring spreading depolarization. In locations where a spreading depolarization passes through, cerebral blood flow can drastically drop within a few seconds and remain suppressed for minutes or even hours, often followed by high-amplitude, sustained hyperemia. In spreading depolarization, neurons lead the event, and the other cells of the neurovascular unit (endothelium, vascular smooth muscle, pericytes, astrocytes, microglia, oligodendrocytes) follow. However, dysregulation in cells of all three supersystems-nervous, vascular, and immune-is very likely involved in the dysfunction of the neurovascular unit underlying spreading ischemia. It is assumed that subarachnoid blood, which lies directly on the cortex and enters the parenchyma via glymphatic channels, triggers these dysregulations. This review discusses the neuroglial, neurovascular, and neuroimmunological dysregulations in the context of spreading depolarization and spreading ischemia as critical elements in the pathogenesis of cortical infarcts after subarachnoid hemorrhage.

Neutrophils and Neutrophil Extracellular Traps Cause Vascular Occlusion and Delayed Cerebral Ischemia After Subarachnoid Hemorrhage in Mice

BACKGROUND

After subarachnoid hemorrhage (SAH), neutrophils are deleterious and contribute to poor outcomes. Neutrophils can produce neutrophil extracellular traps (NETs) after ischemic stroke. Our hypothesis was that, after SAH, neutrophils contribute to delayed cerebral ischemia (DCI) and worse outcomes via cerebrovascular occlusion by NETs.

METHODS

SAH was induced via endovascular perforation, and SAH mice were given either a neutrophil-depleting antibody, a PAD4 (peptidylarginine deiminase 4) inhibitor (to prevent NETosis), DNAse-I (to degrade NETs), or a vehicle control. Mice underwent daily neurological assessment until day 7 and then euthanized for quantification of intravascular brain NETs (iNETs). Subsets of mice were used to quantify neutrophil infiltration, NETosis potential, iNETs, cerebral perfusion, and infarction. In addition, NET markers were assessed in the blood of aneurysmal SAH patients.

RESULTS

In mice, SAH led to brain neutrophil infiltration within 24 hours, induced a pro-NETosis phenotype selectively in skull neutrophils, and caused a significant increase in iNETs by day 1, which persisted until at least day 7. Neutrophil depletion significantly reduced iNETs, improving cerebral perfusion, leading to less neurological deficits and less incidence of DCI (16% versus 51.9%). Similarly, PAD4 inhibition reduced iNETs, improved neurological outcome, and reduced incidence of DCI (5% versus 30%), whereas degrading NETs marginally improved outcomes. Patients with aneurysmal SAH who developed DCI had elevated markers of NETs compared with non-DCI patients.

CONCLUSIONS

After SAH, skull-derived neutrophils are primed for NETosis, and there are persistent brain iNETs, which correlated with delayed deficits. The findings from this study suggest that, after SAH, neutrophils and NETosis are therapeutic targets, which can prevent vascular occlusion by NETs in the brain, thereby lessening the risk of DCI. Finally, NET markers may be biomarkers, which can predict which patients with aneurysmal SAH are at risk for developing DCI.

Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios and prognosis after aneurysmal subarachnoid hemorrhage: a cohort study

BACKGROUND

 Subarachnoid hemorrhage (SAH) prognosis remains poor. Vasospasm mechanism might be associated with inflammation. Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been studied as inflammation markers and prognostic predictors.

OBJECTIVE

 We aimed to investigate NLR and PLR in admission as predictors of angiographic vasospasm and functional outcome at 6 months.

METHODS

 This cohort study included consecutive aneurysmal SAH patients admitted to a tertiary center. Complete blood count was recorded at admission before treatment. White blood cell count, neutrophil count, lymphocyte count, platelet count, NLR, and PLR were collected as independent variables. Vasospasm occurrence-modified Rankin scale (mRS), Glasgow outcome scale (GOS), and Hunt-Hess score at admission and at 6 months were recorded as dependent variables. Multivariable logistic regression models were used to adjust for potential confounding and to assess the independent prognostic value of NLR and PLR at admission.

RESULTS

 A total of 74.1% of the patients were female, with mean age of 55.6 ± 12.4 years. At admission, the median Hunt-Hess score was 2 (interquartile range [IQR] 1), and the median mFisher was 3 (IQR 1). Microsurgical clipping was the treatment for 66.2% of the patients. Angiographic vasospasm incidence was 16.5%. At 6 months, the median GOS was 4 (IQR 0.75), and the median mRS was 3 (IQR 1.5). Twenty-one patients (15.1%) died. Neutrophil-to-lymphocyte ratio and PLR levels did not differ between favorable and unfavorable (mRS > 2 or GOS < 4) functional outcomes. No variables were significantly associated with angiographic vasospasm.

CONCLUSION

 Admission NLR and PLR presented no value for prediction of functional outcome or angiographic vasospasm risk. Further research is needed in this field.

Neutrophil-to-lymphocyte ratio predicted cerebral infarction and poor discharge functional outcome in aneurysmal subarachnoid hemorrhage: A propensity score matching analysis

Background

Neutrophil-lymphocyte-ratio (NLR) and platelet-lymphocyte-ratio (PLR) have emerged as potential biomarkers in predicting the outcomes of aneurysmal subarachnoid hemorrhage (aSAH). Since a study was never conducted on the Southeast Asian and Indonesian population, we designed the present study to evaluate the potential of NLR and PLR in predicting cerebral infarction and functional outcomes and find the optimal cutoff value.

Methods

We retrospectively reviewed patients admitted for aSAH in our hospital between 2017 and 2021. The diagnosis was made using a computed tomography (CT) scan or magnetic resonance imaging and CT angiography. Association between admission NLR and PLR and the outcomes were analyzed using a multivariable regression model. A receiver operating characteristic (ROC) analysis was done to identify the optimal cutoff value. A propensity score matching (PSM) was then carried out to reduce the imbalance between the two groups before comparison.

Results

Sixty-three patients were included in the study. NLR was independently associated with cerebral infarction (odds ratio, OR 1.197 [95% confidence interval, CI 1.027-1.395] per 1-point increment; P = 0.021) and poor discharge functional outcome (OR 1.175 [95% CI 1.036-1.334] per 1-point increment; P = 0.012). PLR did not significantly correlate with the outcomes. ROC analysis identified 7.09 as the cutoff for cerebral infarction and 7.50 for discharge functional outcome. Dichotomizing and performing PSM revealed that patients with NLR above the identified cutoff value significantly had more cerebral infarction and poor discharge functional outcome.

Conclusion

NLR demonstrated a good prognostic capability in Indonesian aSAH patients. More studies should be conducted to find the optimal cutoff value for each population.

Systemic Immune-Inflammation Index Predicts Acute Symptomatic Hydrocephalus After Spontaneous Nonaneurysmal Subarachnoid Hemorrhage

OBJECTIVE

The authors sought to investigate the association between white blood cell counts and acute hydrocephalus in spontaneous nonaneurysmal subarachnoid hemorrhage (nSAH).

METHODS

We conducted a retrospective analysis of 105 consecutive patients with spontaneous nSAH. Univariate and multivariable logistic regression analyses were performed to investigate factors associated with hydrocephalus. Receiver operating characteristic curve analysis determined the optimal cutoff to differentiate between patients with and without hydrocephalus. The admission characteristics of hydrocephalic patients with aneurysmal and nSAH were compared.

RESULTS

A total of 70 patients met inclusion criteria, of which 21 (30%) presented with hydrocephalus. In univariate logistic regression, leukocytes, neutrophils, lymphocytes, neutrophil-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, neutrophil-monocyte-to-lymphocyte ratio, and the systemic immune-inflammation (SII) index ([neutrophils × platelets/lymphocytes]/1000) were associated with hydrocephalus. After adjustments, the SII index independently predicted acute hydrocephalus with the highest odds among laboratory values (odds ratio 2.184, P = 0.006). Receiver operating characteristic curve analysis revealed the SII index differentiated between patients with and without hydrocephalus (area under the curve = 0.799, 95% CI: 0.688-0.909, P < 0.001) with an optimal cutoff of 1.385 103/μL. SII indices did not differ between aneurysmal and nSAH patients with hydrocephalus (3.5 vs. 3.6 103/μL, P = 0.795).

CONCLUSIONS

A SII index ≥1.385 103/μL on admission predicts acute hydrocephalus in spontaneous nSAH. Hydrocephalic patients with aneurysmal and nSAH exhibit similar SII indices, and thus, an exaggerated inflammatory and thrombotic response follows spontaneous subarachnoid hemorrhage irrespective of hemorrhage etiology.

Laboratory biomarkers of delayed cerebral ischemia following subarachnoid hemorrhage: A systematic review

Delayed cerebral ischemia (DCI) substantially contributes to disability and death in subarachnoid hemorrhage (SAH) patients; however, its pathophysiology is incompletely understood and diagnostic and therapeutic strategies are lacking. Biomarkers may help to elucidate the pathophysiology, optimize early diagnosis, or provide treatment targets. We systematically searched PubMed and Embase on October 13, 2021, for studies that evaluated at least one laboratory biomarker in patients with DCI, using the most up-to-date definition of DCI as proposed by a panel of experts in 2010. Quality of studies was assessed using the Newcastle-Ottawa Scale or Cochrane Collaboration’s risk of bias assessment tool. Biomarkers of clinical and radiological DCI were analyzed separately. Results were meta-analyzed if possible, otherwise narratively reviewed. Biomarkers were classified as significant, inconclusive, or nonsignificant. We defined validated biomarkers as those with significant results in meta-analyses, or in at least two studies using similar methodologies within the same time interval after SAH. The search yielded 209 articles with 724 different biomarkers; 166 studies evaluated 646 biomarkers of clinical DCI, of which 141 were significant and 7 were validated biomarkers (haptoglobulin 2-1 and 2-2, ADAMTS13, vWF, NLR, P-selectin, F2-isoprostane); 78 studies evaluated 165 biomarkers of radiological DCI, of which 63 were significant and 1 was a validated biomarker (LPR). Hence, this review provides a selection of seven biomarkers of clinical DCI and one biomarker of radiological DCI as most promising biomarkers of DCI. Future research should focus on determining the exact predictive, diagnostic, and therapeutic potentials of these biomarkers.

A novel nomogram model for clinical outcomes of severe subarachnoid hemorrhage patients

Background

Systemic responses, especially inflammatory responses, after aneurysmal subarachnoid hemorrhage (SAH) are closely related to clinical outcomes. Our study aimed to explore the correlation between the systemic responses in the acute stage and the mid-term outcomes of severe SAH patients (Hunt-Hess grade III-V).

Materials and methods

Severe SAH patients admitted to Jinling Hospital from January 2015 to December 2019 were retrospectively analyzed in the study. The univariate and multivariate logistic regression analyses were used to explore the risk factors of 6-month clinical outcomes in severe SAH patients. A predictive model was established based on those risk factors and was visualized by a nomogram. Then, the predictive nomogram model was validated in another severe SAH patient cohort from January 2020 to January 2022.

Results

A total of 194 patients were enrolled in this study. 123 (63.4%, 123 of 194) patients achieved good clinical outcomes at the 6-month follow-up. Univariate and multivariate logistic regression analysis revealed that age, Hunt-Hess grade, neutrophil-to-lymphocyte ratio (NLR), and complications not related to operations were independent risk factors for unfavorable outcomes at 6-month follow-up. The areas under the curve (AUC) analysis showed that the predictive model based on the above four variables was significantly better than the Hunt-Hess grade (0.812 vs. 0.685, P = 0.013). In the validation cohort with 44 severe SAH patients from three different clinical centers, the AUC of the prognostic nomogram model was 0.893.

Conclusion

The predictive nomogram model could be a reliable predictive tool for the outcome of severe SAH patients. Systemic inflammatory responses after SAH and complications not related to operations, especially hydrocephalus, delayed cerebral ischemia, and pneumonia, might be the important risk factors that lead to poor outcomes in severe SAH patients.

Systemic Inflammatory Response in Spontaneous Subarachnoid Hemorrhage from Aneurysmal Rupture versus Subarachnoid Hemorrhage of Unknown Origin

OBJECTIVE

It is well known that spontaneous non-aneurysmal subarachnoid hemorrhage (SAH), also known as sine materia SAH (smSAH), has usually a better course and prognosis than its aneurysmal counterpart (aSAH). This might depend on different inflammatory mechanisms initiated by bleeding events of different origins. The aim of the present study was to explore the systemic inflammatory response in spontaneous SAH, comparing aSAH and smSAH.

METHODS

We performed a prospective observational study over a consecutive series of patients with SAH. For these patients, we collected all clinical data and, furthermore, performed venous blood sampling over six time points to analyze blood cells. We further performed the analysis of lymphocytes and monocytes by means of flow cytometry to quantify common subtypes. Statistical analysis included a t-student test, Chi-square test, multivariate logistic regression, and ROC analysis.

RESULTS

48 patients were included: six (12.5%) with a diagnosis of spontaneous smSAH, and forty-two patients (87.5%) with aSAH. Significant differences on Day 0 were found for neutrophils and a systemic neuro-inflammatory index, namely, systemic inflammatory response index (SIRI). At the ROC analysis, neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and SIRI exhibited satisfactory predictive power on day 0. At the multivariable logistic regression analysis, the combined index (NLR, LMR, SIRI at day 0) yielded an OR of 0.59 (95% CI 0.29-1.21]). LMR at day 0 yielded an OR of 1.25 ([95% CI 0.94-1.68]), NLR at day 0 exhibited an OR of 0.68 ([95% CI 0.42-1.09]), and SIRI at day 0 displayed an OR of 0.31 ([95% CI 0.06-1.49]).

CONCLUSION

This preliminary study indicated a possible role of some inflammatory indices that point out the importance of innate and adaptive immunity in the etiopathogenetic mechanisms. Drugs modulating these responses could eventually counteract or, at least, reduce secondary damage associated with SAH.

Neutrophil to lymphocyte ratio predicting poor outcome after aneurysmal subarachnoid hemorrhage: A retrospective study and updated meta-analysis

Background

The relationship between neutrophil to lymphocyte ratio (NLR) and poor outcome of aneurysmal subarachnoid hemorrhage (aSAH) is controversial. We aim to evaluate the relationship between NLR on admission and the poor outcome after aSAH.

Method

Part I: Retrospective analysis of aSAH patients in our center. Baseline characteristics of patients were collected and compared. Multivariate analysis was used to evaluate parameters independently related to poor outcome. Receiver operating characteristic (ROC) curve analysis was used to determine the best cut-off value of NLR. Part II: Systematic review and meta-analysis of relevant literature. Related literature was selected through the database. The pooled odds ratio (OR) and corresponding 95% confidence interval (CI) were calculated to evaluate the correlation between NLR and outcome measures.

Results

Part I: A total of 240 patients with aSAH were enrolled, and 52 patients had a poor outcome. Patients with poor outcome at 3 months had a higher admission NLR, Hunt & Hess score, Barrow Neurological Institute (BNI) scale score, Subarachnoid Hemorrhage Early Brain Edema Score (SEBES), and proportion of hypertension history. After adjustment, NLR at admission remained an independent predictor of poor outcome in aSAH patients (OR 0.76, 95% CI 0.69-0.83; P < 0.001). The best cut-off value of NLR in ROC analysis is 12.03 (area under the curve 0.805, 95% CI 0.735 - 0.875; P < 0.001). Part II: A total of 16 literature were included. Pooled results showed that elevated NLR was significantly associated with poor outcome (OR 1.31, 95% CI 1.14-1.49; P < 0.0001) and delayed cerebral ischemia (DCI) occurrence (OR 1.32, 95% CI 1.11-1.56; P = 0.002). The results are more reliable in large sample sizes, low NLR cut-off value, multicenter, or prospective studies.

Conclusion

Elevated NLR is an independent predictor of poor outcome and DCI occurrence in aSAH.

Higher cystatin C level increases the risk of delayed cerebral ischemia after endovascular treatment of aneurysmal subarachnoid hemorrhage: a case-control study

Cystatin C (CysC) has been found to be associated with hemorrhagic and ischemic stroke in many studies. However, the association between CysC level and the risk of delayed cerebral ischemia after endovascular treatment of aneurysmal subarachnoid hemorrhage has been reported rarely. Our study was proposed to explore this association. Consecutive patients from June 2015 to February 2021 in this single-center retrospective study were selected. Univariate and multivariate analyses were used to identify potential prognostic risk factors for delayed cerebral ischemia, and the stability of the association was demonstrated by several statistical methods, such as subgroup analysis, interaction testing, generalized linear models, and propensity score matching. A total of 424 patients were included in the analysis. Cystatin C was independently associated with delayed cerebral ischemia. The independent effects of CysC on delayed cerebral ischemia were shown in generalized linear models with a logit link, and the results were relatively stable in crude, partial, and full models with ORs (95% CIs) for delayed cerebral ischemia. Subgroup analysis showed no significant subgroup differences in the effect of CysC on delayed cerebral ischemia. There was also no interaction effect between CysC and other confounders. Patients in the high CysC group had a higher risk of delayed cerebral ischemia than those in the low CysC group before and after propensity score matching. CysC level could be an independent predictor for the risk of delayed cerebral ischemia after endovascular treatment of aneurysmal subarachnoid hemorrhage.

Predictive Value of Hematologic Inflammatory Markers in Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND OBJECTIVE

Our study aimed to determine the ability of hematologic markers (neutrophil/lymphocyte ratio [NLR], platelet/lymphocyte ratio, and red cell distribution width [RDW]) in predicting delayed cerebral ischemia (DCI), modified Rankin Scale scores, and mortality in patients with aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

A retrospective observational 6-year review of medical records was conducted to identify all consecutive patients with aSAH admitted to the largest training hospital in the Philippines. Univariable and multivariable regression analyses were performed to determine the association of the biomarkers with the respective outcomes. Receiver operating characteristic curves were used to detect overall predictive accuracy.

RESULTS

A total of 222 patients with aSAH were included, of whom 11.71% developed DCI. Most patients with NLR ≥5.9 subsequently died (77 vs. 52%; P = 0.03). DCI was also associated with poor functional outcomes with higher modified Rankin Scale scores (3-6) on discharge (92% vs. 49%; P < 0.01), and longer duration of hospitalization (median, 20 vs. 13 days; P = 0.01). In receiver operating characteristic analyses, the value of RDW was predictive for DCI (area under the curve, 0.70; 95% confidence interval, 0.62-0.79; P < 0.01). The values of NLR (area under the curve, 0.67; 95% CI, 0.59-0.74) potentially predict functional outcome. RDW, NLR, and their combinations were poor discriminators of mortality.

CONCLUSIONS

Our study showed that some hematologic parameters analyzed could be of potential value as prognostic biomarkers in patients with aSAH. Hematologic biomarkers are widely available and practical parameters that may be of considerable clinical value in aSAH management, especially in lower-middle-income countries such as the Philippines.

The Prognostic Value of Neutrophil-to-Lymphocyte Ratio in Patients With Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis of Observational Studies

The neutrophil–to-lymphocyte ratio (NLR), as an essential systemic inflammation factor, has been widely used as a prognostic indicator in various diseases, such as malignant tumors, cardiovascular disease, and intracranial hemorrhage. An increasing number of studies have believed that NLR is a valuable predictor of prognosis for patients with aneurysmal subarachnoid hemorrhage (aSAH). However, these results remain controversial. In the current study, we planned to carry out a systematic review and meta-analysis to investigate the association between NLR and poor outcome, and the occurrence of delayed cerebral ischemia (DCI). We carried out a comprehensive search for published literatures on PubMed, EMBASE, Cochrane Library, and Web of Science databases from inception to April 1, 2021. We conducted an assessment of all included studies based on the principles proposed in the Newcastle-Ottawa Quality Assessment Scale (NOS). Poor outcome and the occurrence of DCI were considered as the main outcome measure. We calculated the pooled odds ratio (OR) and corresponding 95% confidence interval (CI) to examine the strength of the association of NLR with poor outcome or the occurrence of DCI. We strictly selected a total of 10 studies comprising 4,989 patients. Nine studies reported the association between NLR and poor outcome, and five studies reported the association between NLR and the occurrence of DCI. The pooled results indicated higher NLR was significantly associated with both poorer outcomes (OR = 1.32, 95%CI 1.11–1.57; P = 0.002, I² = 87%), and the occurrence of DCI (OR = 1.72, 95%CI 1.22–2.41; P = 0.002, I² = 82%) in aSAH patients. The NLR is a valuable indicator of inflammation to independently predict poor outcome and occurrence of DCI after aSAH, where a higher NLR is significantly associated with poor outcomes and occurrence of DCI. These findings suggest that the NLR can help clinicians evaluate the prognosis and identify potentially severe patients early, which may contribute to better management and improve poor prognosis of aSAH patients.

Systemic immune-inflammation index predicts the outcome after aneurysmal subarachnoid hemorrhage

Systemic inflammatory response is closely related to the pathogenesis and prognosis in critical patients. Recently, systemic immune-inflammation index (SII), an indicator of systemic inflammatory response, was proved to predict the outcome in cancerous and non-cancerous diseases. The aim of this study is to investigate the association between SII on admission and 6-month outcome in patients with aneurysmal subarachnoid hemorrhage (aSAH). The clinical data and prognosis of 76 patients with aSAH were analyzed. The 6-month outcome was assessed by the modified Rankin scale(mRS). The unfavorable outcome was defined as mRS score ≥ 3. In addition, multivariate analysis was conducted to investigate factors independently associated with the favorable outcome. Receiver operating characteristic (ROC) curve analysis was undertaken to identify the best cut-off value of SII for the discriminate between favorable and unfavorable outcome in these patients. Thirty-six patients (47.4%) in our study had an unfavorable outcome (mRS ≥ 3) at 6 months, and twenty-four (66.7%) of them were in the high-SII group. A significantly higher SII on admission was observed in patients with unfavorable functional outcome at 6 months. Binary logistic regression analysis showed that there was an independent association between SII on admission and 6-month clinical outcome (adjusted OR = 4.499, 95%CI: 1.242-16.295, P < 0.05). The AUC of the SII for predicting unfavorable outcome was 0.692 (95% CI: 0.571-0.814, P < 0.05). Systemic immune-inflammation index (SII) could be a novel independent prognostic factor for aSAH patients at the early stage of the disease.

Associations between C-reactive protein and white blood cell count, occurrence of delayed cerebral ischemia and poor outcome following aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis

This review and meta-analysis investigated associations of systemic inflammatory marker C-reactive protein (CRP) and white blood cell count (WBC) with occurrence of delayed cerebral ischemia (DCI) and poor functional outcome after aneurysmal subarachnoid hemorrhage (aSAH). Pubmed, EMBASE, and CENTRAL databases were searched until November 30, 2019, selecting prospective and retrospective studies of patients with spontaneous SAH due to ruptured aneurysm. Outcome measures were occurrence of DCI, defined as new focal neurological deficit or a deterioration of consciousness; and/or a new infarct on computed tomography or magnetic resonance imaging that was not visible initially. Occurrence of poor functional outcome at follow-up were measured by modified Rankin Scale or Glasgow outcomes scale. Fifteen studies analyzing data of 3268 patients with aSAH were included. Meta-analysis revealed early increase in CRP was significantly associated with higher risk of occurrence of DCI (pooled OR 1.30, 95% CI 1.10-1.54; P = 0.002), whereas not with poor functional outcome (pooled OR 1.02, 95% CI 1.00-1.04, P = 0.052). No significant associations between early increase in WBC and DCI (pooled OR 1.13, 95% CI 0.95-1.34; P = 0.179) were observed, whereas increase in WBC was significantly associated with increased risk of poor functional outcome (pooled OR 1.17, 95% CI 1.07-1.28, P = 0.001). Early increase in blood CRP appears to correlate with DCI after SAH, while increase in WBC correlates with poor functional outcome. However, strong conclusion cannot be made due to the small study number, between-study heterogeneity and suspicion of uncontrolled factors. Whether early phase CRP and WBC may serve as prognostic markers for aSAH needs more investigation.

Neutrophil Count on Admission Predicts Acute Symptomatic Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

To investigate the association between immunologic counts on admission and acute symptomatic hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

We conducted a retrospective analysis of 143 consecutive patients with aSAH. Patient demographics, clinical parameters, laboratory values, and radiographic imaging were obtained. Univariate and multivariate logistic regression analyses were performed to investigate parameters independently associated with acute symptomatic hydrocephalus. Receiver operating characteristic (ROC) curve analysis determined the best threshold value of neutrophil count to differentiate patients with and without hydrocephalus.

RESULTS

Overall, acute symptomatic hydrocephalus developed in 39.16% of patients. In an adjusted multivariate logistic regression model, Hunt and Hess grade 4-5 (odds ratio [OR]: 16.052, 95% confidence interval [CI]: 1.188-216.983; P = 0.037), modified Fisher score 3-4 (OR: 10.107, 95% CI: 1.715-59.572; P = 0.011), intraventricular hemorrhage (OR: 4.578, 95% CI: 1.417-14.788; P = 0.011), neutrophil count (OR: 1.183, 95% CI: 1.033-1.354; P = 0.015), and prior ischemic stroke (OR: 7.003, 95% CI: 1.293-37.929; P = 0.024) were significantly associated with hydrocephalus. ROC analysis for neutrophil count confirmed an acceptable area under the curve (AUC 0.780, 95% CI: 0.701-0.859; P < 0.001). The best threshold value of neutrophil count to predict hydrocephalus was ≥9.80 × 10³/mL. Overall, 81.25% of patients who developed shunt dependence had a neutrophil count ≥9.80 × 10³/mL on admission (P = 0.003).

CONCLUSIONS

Neutrophil count ≥9.80 × 10³/mL on admission predicts acute symptomatic hydrocephalus after aSAH in an adjusted multivariate logistic regression model. Moreover, shunt dependence was associated with higher neutrophil counts.

Neutrophil Counts as Promising Marker for Predicting In-Hospital Mortality in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Systemic inflammation is recognized as a hallmark of stroke. We aimed to evaluate the prognostic value of various inflammatory factors using blood at admission in patients with aneurysmal subarachnoid hemorrhage.

METHODS

In a multicenter observational study of patients with aneurysmal subarachnoid hemorrhage, the counts of neutrophil, platelet, and lymphocyte were collected on admission. Patients were stratified based on neutrophil counts with propensity score matching to minimize confounding. We calculated the adjusted odds ratios with 95% CIs for the primary outcome of in-hospital mortality and hospital-acquired infections.

RESULTS

A total of 6041 patients were included in this study and 344(5.7%) of them died in hospital. Propensity score matching analyses indicated that compared with the lower neutrophil counts, higher neutrophil counts were associated with increased risk of in-hospital mortality (odds ratio, 1.53 [95% CI, 1.14-2.06]), hospital-acquired infections (odds ratio, 1.61 [95% CI, 1.38-1.79]), and delayed neurological ischemic deficits (odds ratio, 1.52 [95% CI, 1.09-1.97]). Moreover, out of all the inflammatory factors studied, neutrophil counts demonstrated the highest correlation with in-hospital mortality and hospital-acquired infections.

CONCLUSIONS

Among patients with aneurysmal subarachnoid hemorrhage, high neutrophil counts at admission were associated with increased mortality and hospital-acquired infections. The neutrophil count is a simple, useful marker with prognostic value in patients with aneurysmal subarachnoid hemorrhage.

Admission Neutrophil to Lymphocyte Ratio for Predicting Outcome in Subarachnoid Hemorrhage

PURPOSE

We sought to evaluate the relationship between admission neutrophil-to-lymphocyte ratio (NLR) and functional outcome in aneurysmal subarachnoid hemorrhage (aSAH) patients.

MATERIAL AND METHODS

Consecutive patients with aSAH were treated at two tertiary stroke centers during a five-year period. Functional outcome was defined as discharge modified Rankin score dichotomized at scores 0-2 (good) vs. 3-6 (poor).

RESULTS

474 aSAH patients were evaluated with a mean NLR 8.6 (SD 8.3). In multivariable logistic regression analysis, poor functional outcome was independently associated with higher NLR, older age, poorer clinical status on admission, prehospital statin use, and vasospasm. Increasing NLR analyzed as a continuous variable was independently associated with higher odds of poor functional outcome (OR 1.03, 95%CI 1.00-1.07, p=0.05) after adjustment for potential confounders. When dichotomized using ROC curve analysis, a threshold NLR value of greater than 6.48 was independently associated with higher odds of poor functional outcome (OR 1.71, 95%CI 1.07-2.74, p=0.03) after adjustment for potential confounders.

CONCLUSIONS

Higher admission NLR is an independent predictor for poor functional outcome at discharge in aSAH patients. The evaluation of anti-inflammatory targets in the future may allow for improved functional outcome after aSAH.

The Role of the Blood Neutrophil-to-Lymphocyte Ratio in Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is an important type of stroke with the highest rates of mortality and disability. Recent evidence indicates that neuroinflammation plays a critical role in both early brain injury and delayed neural deterioration after aSAH, contributing to unfavorable outcomes. The neutrophil-to-lymphocyte ratio (NLR) is a peripheral biomarker that conveys information about the inflammatory burden in terms of both innate and adaptive immunity. This review summarizes relevant studies that associate the NLR with aSAH to evaluate whether the NLR can predict outcomes and serve as an effective biomarker for clinical management. We found that increased NLR is valuable in predicting the clinical outcome of aSAH patients and is related to the risk of complications such as delayed cerebral ischemia (DCI) or rebleeding. Combined with other indicators, the NLR provides improved accuracy for predicting prognosis to stratify patients into different risk categories. The underlying pathophysiology is highlighted to identify new potential targets for neuroprotection and to develop novel therapeutic strategies.

The Role of NLRP3 Inflammasome in Cerebrovascular Diseases Pathology and Possible Therapeutic Targets

Cerebrovascular diseases are pathological conditions involving impaired blood flow in the brain, primarily including ischaemic stroke, intracranial haemorrhage, and subarachnoid haemorrhage. The nucleotide-binding and oligomerisation (NOD) domain-like receptor (NLR) family pyrin domain (PYD)-containing 3 (NLRP3) inflammasome is a protein complex and a vital component of the immune system. Emerging evidence has indicated that the NLRP3 inflammasome plays an important role in cerebrovascular diseases. The function of the NLRP3 inflammasome in the pathogenesis of cerebrovascular diseases remains an interesting field of research. In this review, we first summarised the pathological mechanism of cerebrovascular diseases and the pathological mechanism of the NLRP3 inflammasome in aggravating atherosclerosis and cerebrovascular diseases. Second, we outlined signalling pathways through which the NLRP3 inflammasome participates in aggravating or mitigating cerebrovascular diseases. Reactive oxygen species (ROS)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), ROS/thioredoxin-interacting protein (TXNIP) and purinergic receptor-7 (P2X7R) signalling pathways can activate the NLRP3 inflammasome; activation of the NLRP3 inflammasome can aggravate cerebrovascular diseases by mediating apoptosis and pyroptosis. Autophagy/mitochondrial autophagy, nuclear factor E2-related factor-2 (Nrf2), interferon (IFN)-β, sirtuin (SIRT), and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) reportedly alleviate cerebrovascular diseases by inhibiting NLRP3 inflammasome activation. Finally, we explored specific inhibitors of the NLRP3 inflammasome based on the two-step activation of the NLRP3 inflammasome, which can be developed as new drugs to treat cerebrovascular diseases.

Systemic Inflammation Response Index and Systemic Immune-inflammation Index for Predicting the Prognosis of Patients with Aneurysmal Subarachnoid Hemorrhage

OBJECTIVES

Inflammatory response plays a pivotal role in the progress of aneurysmal subarachnoid hemorrhage (aSAH). As novel inflammatory markers, systemic inflammation response index (SIRI) and systemic immune-inflammation (SII) index could reflect clinical outcomes of patients with various diseases. The aim of this study was to ascertain whether initial SIRI and SII index were associated with prognosis of aSAH patients.

METHODS

A total of 680 patients with aSAH were enrolled. Their prognosis was evaluated with modified Rankin Scale (mRS) at 3 months, and unfavorable clinical outcome was defined as mRS score of 3-6. Receiver operating characteristic (ROC) curve analysis was performed to identify cutoff values of SIRI and SII index for predicting clinical outcomes. Univariate and multivariate regression analyses were performed to explore relationships of SIRI and SII index with prognosis of patients.

RESULTS

Optimal cutoff values of SIRI and SII index to discriminate between favorable and unfavorable clinical outcomes were 3.2 × 10⁹/L and 960 × 10⁹/L, respectively (P < 0.001 and 0.004, respectively). In multivariate analysis, SIRI value ≥ 3.2 × 10⁹/L (odds ratio [OR]: 1.82, 95% CI: 1.46-3.24; P = 0.021) and SII index value ≥ 960 × 10⁹/L (OR: 1.68, 95% CI: 1.24-2.74; P = 0.040) were independent predicting factors for poor prognosis after aSAH.

CONCLUSIONS

SIRI and SII index values are associated with clinical outcomes of patients with aSAH. Elevated SIRI and SII index could be independent predicting factors for a poor prognosis after aSAH.

Monocyte-based inflammatory indices predict outcomes following aneurysmal subarachnoid hemorrhage

The contribution of specific immune cell populations to the post-hemorrhagic inflammatory response in aneurysmal subarachnoid hemorrhage (aSAH) and correlations with clinical outcomes, such as vasospasm and functional status, remains unclear. We aimed to compare the predictive value of leukocyte ratios that include monocytes as compared to the neutrophil-to-lymphocyte ratio (NLR) in aSAH. A prospectively accrued database of consecutive patients presenting to our institution with aSAH between January 2013 and December 2018 was used. Patients with signs and symptoms of infection (day 1-3) were excluded. Admission values of the NLR, monocyte-neutrophil-to-lymphocyte ratio (M-NLR), and lymphocyte-to-monocyte ratio (LMR) were calculated. Associations with functional status, the primary outcome, and vasospasm were evaluated using univariable and multivariable logistic regression analyses. In the cohort of 234 patients with aSAH, the M-NLR and LMR, but not the NLR, were significantly associated with poor functional status (modified Rankin scale > 2) at 12-18 months following discharge (p = 0.001, p = 0.023, p = 0.161, respectively). The area under the curve for predicting poor functional status was significantly lower for the NLR (0.543) compared with the M-NLR (0.603, p = 0.024) and LMR (0.608, p = 0.040). The M-NLR (OR = 1.01 [1.01-1.02]) and LMR (OR = 0.88 [0.78-0.99]) were independently associated with poor functional status while controlling for age, hypertension, Fisher grade, and baseline clinical status. The LMR was significantly associated with vasospasm (OR = 0.84 [0.70-0.99]) while adjusting for age, hypertension, Fisher grade, aneurysm size, and current smoking. Inflammatory indices that incorporate monocytes (e.g., M-NLR and LMR), but not those that include only neutrophils, predict outcomes after aSAH.

Is neutrophil-lymphocyte ratio a useful tool for predicting outcome in subarachnoid hemorrhage? A systematic review

Ruptured intracranial aneurysms, as the leading cause of spontaneous subarachnoid hemorrhage (aSAH), represents an emergency with high morbi-mortality. The comprehension of the underlying pathology that involves inflammatory and immune responses, through the neutrophil-to-lymphocyte ratio (NLR), could help to predict complications such as delayed cerebral ischemia (DCI) or rebleeding and the functional outcome. Systematic review of English-based literature through PubMed and Biblioteca Vitural em Saúde (BVS) to find papers discussing the use of NLR in the aSAH setting. Area-under-curve (AUC) of receiver operating characteristics (ROC), cutoff value, sensitivity, and specificity were retrieved. From 53 articles included, 4 papers were evaluated after exclusion criteria. Rebleeding could be predicted with a NLR cutoff value of 9.88 (sensitivity 72.3%, specificity 63.3%). The mean cutoff value for DCI was 12.85, with sensitivity 66.3% and specificity 75.8%. Finally, a worse 3-month functional outcome could be predicted with a mean sensitivity of 73.3% and a mean specificity of 54%. NLR is a new issue in scientific community, especially neurosurgery. The current understanding points to a multifactorial process after aSAH that emerges as alterations on the NLR. As a measurement readily available and cost-effect after admission of the patient, its use signals that patients that need expedite surgical treatment or more aggressive treatment for vasospasm. As other medical subspecialties already use this ratio to predict outcomes, the literature reviewed by this paper constitute the earliest clues that higher NLR predicts re-bleeding, DCI, and functional outcome.

The potential for immune checkpoint modulators in cerebrovascular injury and inflammation

Introduction: Neuroinflammation has been linked to poor neurologic and functional outcomes in many cerebrovascular disorders. Immune checkpoints are upregulated in the setting of traumatic brain injury, intracerebral hemorrhage, ischemic stroke, central nervous systems vasculitis, and post-hemorrhagic vasospasm, and are potential mediators of pathologic inflammation. Burgeoning evidence suggests that immune checkpoint modulation is a promising treatment strategy to decrease immune cell recruitment, cytokine secretion, brain edema, and neurodegeneration.Areas covered: This review discusses the role of immune checkpoints in neuroinflammation, and the potential for therapeutic immune checkpoint modulation in inflammatory cerebrovascular disorders. A search of Pubmed and clinicaltrials.gov was performed to find relevant literature published within the last 50 years.Expert opinion: The clinical success of immune-activating checkpoint modulators in human cancers has shown the immense clinical potential of checkpoint-based immunotherapy. Given that checkpoint blockade can also precipitate a pathologic pro-inflammatory or autoimmune response, it is plausible that these pathways may also be targeted to quell aberrant inflammation. A limited but growing number of studies suggest that immune checkpoints play a critical role in regulating the immune response in the central nervous system in a variety of contexts, and that immune-deactivating checkpoint modulators may be a promising treatment strategy for acute and chronic neuroinflammation in cerebrovascular disorders.

Clinical Relevance of Changes in Peripheral Blood Cells After Intracranial Aneurysm Rupture

BACKGROUND

The rupture of an intracranial aneurysm (IA) causes a systemic response that involves an immune/inflammatory reaction. We sought to characterize the systemic response to IA rupture.

METHODS

We included 19 patients in the acute phase of IA rupture and 20 control subjects. Flow cytometry was used to analyze alterations in the level of mononuclear leukocytes. Cell-related parameters, including the neutrophil-to-lymphocyte ratio (NL-R), lymphocyte-to-monocyte ratio (LM-R), platelet-to-lymphocyte ratio (PL-R), and systemic immune-inflammation index (SII), were calculated, and the relationship between the analyzed hematological parameters and clinical status was investigated.

RESULTS

Patients with ruptured IAs presented with significantly higher white blood cells (WBC) and neutrophil counts but lower lymphocyte counts than control subjects. NL-R and SII values were higher and the LM-R was lower in the acute phase after IA rupture. Analyzing the severity of clinical status and the outcome of patients with subarachnoid hemorrhage, we found that patients with poor clinical status, as measured by the Glasgow Coma Scale (GCS) and the Hunt and Hess scale, had significantly lower lymphocyte counts and higher NL-R, PL-R and SII values than those with good clinical status. Additionally, patients with lower GCS scores presented a lower proportion of CD3+CD4-CD8- cells. Worse outcomes assessed at discharge were associated with lower lymphocyte counts but higher PL-R values.

CONCLUSIONS

The current study pointed to the significance of systemic immune and inflammatory responses after IA rupture and the potential clinical utility of hematological parameters, which can be easily calculated. In particular, the role of DN T cells and the significance of the SII as a marker related to clinical status should be further investigated.

Development and validation of a predictive model for the prognosis in aneurysmal subarachnoid hemorrhage

Background

This study was to conduct a predictive model for the prognosis of aneurysmal subarachnoid hemorrhage (aSAH) and validate the clinical data.

Methods

A total of 235 aSAH patients were enrolled in this study, dividing into the favorable or poor prognosis groups based on Modified Rankin Scale (mRS) at 3 months postoperatively. Multivariate analysis was assessed using binary Logistic regression and Fisher discriminant analysis. The receiver operating characteristic (ROC) curve was used to determine the cut‐off value.

Results

Our findings showed that the high Glasgow Coma Scale (GCS) score 24‐hour after surgery reduced the risk of poor prognosis, and the surgical clipping and elevated neutrophil‐lymphocyte ratio (NLR) increased the risk of poor prognosis. The discriminant function was V = 0.881 × GCS score − 0.523 × NLR − 0.422 × therapeutic approach, and V = −0.689 served as a cut‐off value. When V ≥ −0.689, the good prognosis was considered among these patients with aSAH. The correctness for predicting the prognostic outcomes by self‐validation was 85.11%.

Conclusion

This predictive model established by a discriminant analysis is a useful tool for predicting the prognostic outcomes of aSAH patients, which may help clinicians identify patients at high risk for poor prognosis and optimize treatment after surgery.

Peripheral Monocytosis at Admission to Predict Cerebral Infarct and Poor Functional Outcomes in Subarachnoid Hemorrhage Patients

OBJECTIVE

Increasing evidence points monocytes' role to be larger than thought in developing cerebral infarction (CI) after subarachnoid hemorrhage (SAH). However, there is no clinical evidence of the relationship between peripheral monocytes and CI and clinical outcomes. Therefore we determine whether an increase in monocytes in the acute phase is useful to predict CI and functional outcomes in SAH patients.

METHODS

We included 204 patients with an SAH diagnosis. We collected patient-related factors, comorbidities, Hunt-Hess grade, modified Fisher grade, treatment, delayed cerebral ischemia, CI, aneurysm characteristics, and peripheral monocytes from vein blood at admission. Poor outcomes were defined as modified Rankin Scale score ≥3.

RESULTS

Fifty (24.5%) patients had CI before discharge. In a multivariate model, increased monocytes at admission were significantly associated with CI after adjusting for IV-V Hunt-Hess grade and delayed cerebral ischemia (odds ratio: 3.193, 95% confidence interval: 1.069-9.532, P = 0.037). In receiver operating characteristic curve analysis, a monocyte count of 0.60 was identified as the best cutoff value to discriminate the development of CI (area under the curve = 0.622, P = 0.010; CI for monocytes <0.60 17.4% vs. CI for monocytes ≥0.60 29.1% P = 0.046). Admission monocytes ≥0.60 predicted poor functional outcomes at discharge (monocytes <0.60 52% vs. monocytes ≥0.60 64.7%) and at 12 months (monocytes <0.60 29.4% vs. monocytes ≥0.60 70.6%).

CONCLUSIONS

Increased peripheral monocytes at admission is a risk factor for developing CI after SAH. Moreover, short- and long-term poor clinical outcomes were associated with higher monocyte count. Therefore monocytes could be a convenient biomarker for prognosis unfavorable outcomes and a possible target for new therapeutic strategies.

Admission Neutrophil-Lymphocyte Ratio Predicts Rebleeding Following Aneurismal Subarachnoid Hemorrhage

OBJECTIVE

The relationship between neutrophil-lymphocyte ratio (NLR) and the occurrence of rebleeding in aneurysmal subarachnoid hemorrhage (aSAH) is poorly understood. Our study aimed to investigate the association between NLR on admission and rebleeding following aSAH.

METHODS

Clinical and laboratorial data from patients with aSAH were retrospectively collected, including leukocyte, neutrophil, lymphocyte, and NLR. Univariate and multivariate analyses were performed to assess for the association of NLR with rebleeding. We performed propensity-score matching analyses to correct imbalances in patient characteristics between the rebleeding group and nonrebleeding group.

RESULTS

Rebleeding occurred in 30 of 716 (4.19%) patients with aSAH in this cohort. Patients with rebleeding had significantly higher NLR comparing with patients without rebleeding (11.27 vs. 5.5; P < 0.05) in the univariate analysis. In the multivariate analysis, NLR was considered as a risk factor of rebleeding (odds ratio, 0.283; 95% confidence interval, 0.130-0.620; P = 0.002), as well as Fisher grade (odds ratio, 0.353, 95% confidence interval, 0.151-0.824; P = 0.016). The area under the curve of the NLR and combined NLR-Fisher grade model was 0.702 and 0.744 (sensitivity was 39.94%, and specificity was 100%) for predicting rebleeding, respectively. After propensity-score matching, the optimal cutoff value for NLR as a predictor for rebleeding following aSAH was determined as 5.4 (sensitivity was 83.33%, and the specificity was 63.33%).

CONCLUSIONS

Higher NLR predicts the occurrence of rebleeding and poor outcome, and NLR combined with Fisher grade significantly improves the prediction of rebleeding following aSAH.

Could Neutrophil-to-Lymphocyte Ratio (NLR) Serve as a Potential Marker for Delirium Prediction in Patients with Acute Ischemic Stroke? A Prospective Observational Study

Delirium is an acute brain disorder that commonly occurs in patients with acute ischemic stroke (AIS). Pathomechanism of delirium is related to the neuroinflammatory process and oxidative stress. Search for readily available diagnostic marker that will aid clinicians in early identification of delirium is ongoing. The aim of this study was to investigate whether neutrophil-to-lymphocyte ratio (NLR) could serve as a potential marker for delirium prediction in patients with AIS and to find an easy diagnostic tool using laboratory and clinical parameters to predict delirium. Prospective observational study (NCT03944694) included patients with AIS admitted to the neurology department of a district general hospital. All patients were screened for delirium using CAM-ICU (Confusion Assessment Method for Intensive Care Unit). Demographic and medical history data and admission lab results, including differential white blood cell analysis, were collected from all patients. We included 1001 patients in the final analysis. The mean age of the sample was 71 years, and 52% of patients were males. The incidence of early-onset delirium was 17.2%. The NLR was elevated in delirious patients (6.39 ± 8.60 vs. 4.61 ± 5.61, p < 0.001). The best cut-off value of NLR to predict delirium using the receiver operating characteristics (ROC) was determined at 4.86. Multivariable logistic regression analysis showed that the odds ratio (OR) for developing delirium with NLR > 4.86 (adjusted for age, sex, body mass index (BMI), comorbidities, and baseline neurology) was 1.875 (95% CI 1.314-2.675, p = 0.001). As a result of different combinations of markers and clinical parameters based on logistic regression, a formula-DELirium in Acute Ischemic Stroke (DELIAS score)-was obtained with the area under the ROC curve of 0.801 (p < 0.001). After regression of the cut-off points of the obtained curve, a significant correlation of the DELIAS score was observed with the occurrence of early-onset delirium (OR = 8.976, p < 0.001) and with delirium until the fifth day after AIS (OR = 7.744, p < 0.001). In conclusion, NLR can be regarded as a potential marker for prediction of early-onset delirium after AIS. On the basis of combined laboratory and clinical parameters, the DELIAS score was calculated, which gave the highest predictive value for delirium in the analyzed group of patients after ischemic stroke. However, further studies are needed to validate these findings.