Skip to main content
Download PDF

Neutrophil-to-lymphocyte ratio associated with symptomatic saccular unruptured intracranial aneurysm

European Journal of Medical Research volume 29, Article number: 40 (2024) Cite this article

Abstract

Background and purpose

Whether symptomatic unruptured intracranial aneurysms (UIAs) lead to change in circulating inflammation remains unclear. This study aims to evaluate the role of hematological inflammatory indicators in predicting symptomatic UIA.

Methods

Adult patients diagnosed with saccular intracranial aneurysm from March 2019 to September 2023 were recruited retrospectively. Clinical and laboratory data, including the white blood cells (WBC), neutral counts (NEUT), lymphocyte counts (LYM), and monocyte counts (MONO) of each patient, were collected. The neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) were calculated as NLR = NEUT/LYM, LMR = LYM/MONO, SII = PLT*NEUT/LYM. The hematological inflammatory indicators were compared in symptomatic saccular and asymptomatic UIA patients. Multivariable logistic regression analyses were performed to explore the factors predicting symptomatic UIA.

Results

One hundred and fifty UIA patients with a mean age of 58.5 ± 12.4 were included, of which 68% were females. The NLR and LMR were significantly associated with symptomatic UIA, and the association remained in small UIAs (< 7 mm). The multiple logistic regression analysis showed that NLR was independently associated with symptomatic UIA. On ROC curve analysis, the optimal cutoff value of NLR to differentiate symptomatic from asymptomatic was 2.38. In addition, LMR was significantly associated with symptomatic UIA smaller than 7 mm.

Conclusion

There was a significant correlation between NLR and symptomatic UIA. The NLR was independently associated with symptomatic UIA.

Introduction

Unruptured intracranial aneurysms (UIAs) are pathologically confined dilations of the intracranial artery walls with a population prevalence of approximately 3.2%. They are the main cause of spontaneous subarachnoid hemorrhage (SAH) [1]. Once an aneurysm ruptures, the disability and mortality rates are very high. Inflammation is thought to play an important role in the development, progression, and rupture of the intracranial aneurysm [2,3,4,5]. A large number of macrophages, white blood cells (WBCs), and inflammatory factors are observed in the ruptured intracranial aneurysm tissues and peripheral blood of aneurysmal SAH patients [6,7,8].

Previous studies have shown that the risk of rupture was significantly higher in symptomatic UIA patients than in asymptomatic patients [11]. In addition, the aneurysm wall enhancement (AWE) on high-resolution vessel wall imaging (HR-VWI) was significantly associated with symptomatic UIA [9,10,11,12,13]. As AWE is a manifestation of local inflammation [14,15,16,17,18,19], it is believed that the local inflammation level increases in symptomatic UIA. Moreover, it was reported that the neutrophil-to-lymphocyte ratio (NLR), a widely recognized circulating inflammation marker, was significantly associated with AWE of UIA [20]. However, the change in circulating inflammatory indicators in symptomatic UIA patients remains unclear. This study aimed to assess the correlation between the level of circulating inflammatory indicators and symptomatic UIAs.

Materials and methods

Study population

Eighty-eight consecutive patients with saccular UIAs were identified from a prospectively maintained database between March 2019 and September 2023 at the department of Neurosurgery, Guangdong Provincial Hospital of Traditional Chinese Medicine, and Nanfang Hospital of Southern Medical University. The study protocols were approved by the ethics committees of Guangdong Provincial Hospital of Traditional Chinese Medicine (IRB number: ZE2023-183-01).

The inclusion criteria were the diagnosis of IAs, age > 18 years, and saccular UIA identified on MR angiography or DSA. UIA patients who were regarded as symptomatic were as follows: acute headache (intense headache at onset with resolution in the following 72 h); chronic or recurrent headache (headache disappeared or with a marked improvement after surgical intervention of the aneurysm) [13, 21]; or cranial nerve palsy (such as the third, second, fourth, fifth and sixth nerve palsy) [22] caused by the unruptured intracranial aneurysms. Aneurysm status which was symptomatic or evolving during following up was defined as unstable UIAs. Patients with a known history of infection, stroke, heart disease, autoimmune disease, hematological diseases, cancer, and chronic liver and kidney insufficiency were excluded from this study.

The clinical data, including age, sex, hypertension, diabetes, current smoking, and drinking status, were recorded. Moreover, we acquired data, including the number, location, size, and morphology of aneurysms. PHASES score of every aneurysm was calculated.

Blood examination

All patients underwent complete blood cell count analysis within 24 h after admission. The WBC, neutral counts (NEUT), lymphocyte counts (LYM), monocyte counts (MONO), platelet counts (PLT) of each patient were recorded. The NLR, Systemic Immune-Inflammation Index (SII), and lymphocyte-to-monocyte ratio (LMR) of each patient were calculated as follows: NLR = NEUT/LYM, LMR = LYM/MONO, SII = PLT* NEUT/LYM.

Statistical analysis

We used SPSS 22.0 software for statistical analysis. Laboratory data, such as the NLR, LMR, SII, WBC, NEUT, LYM, and MONO, which obeying normal distribution were presented as mean ± SD and were compared using the student’s t-test. The clinical data such as sex, hypertension, diabetes, and current smoking were expressed as the number of cases and percentage. They were compared with the different groups using Fisher's exact or chi-square test. P < 0.05 was considered statistically significant. Multivariate logistic regression analyses were conducted to determine which factors were independent risk factors for symptomatic UIA after adjusting for variables with p < 0.1 in the univariate comparisons. The NLR value for identifying symptomatic from asymptomatic UIAs was analyzed using receiver operating characteristic (ROC) curve analysis.

Results

Clinical characteristics

During a 4-year study period, 226 patients with UIAs were retrospectively identified. After excluding patients for either defined criterion, 150 patients with saccular UIAs were included in this study, among them 85 located in ICA, 20 located in MCA, 45 located in posterior circulation. Seventy-six patients were excluded: 28 patients with fusiform aneurysms, 8 patients with a known history of infection, 21 patients with stroke, 12 patients with heart disease, 6 patients with cancer, and 1 patient with kidney insufficiency were excluded from this study. There were 54 symptomatic patients, among them, 9 had cranial nerve palsy, 28 had acute headache, 12 had chronic headache, 5 had recurrent headache. The characteristics of the patients and aneurysms are shown in Table 1.

Table 1 Characteristics of aneurysm and laboratory parameter in symptomatic and asymptomatic UIA patients
Full size table

NLR was independently associated with symptomatic UIA

The aneurysm size was larger in the symptomatic UIA group than in the asymptomatic group (6.29 mm vs. 4.56 mm, p = 0.024). Symptomatic UIA patients were more likely to have higher levels of NLR (p = 0.017) and low levels of LMR and LYM (p = 0.050, p = 0.092, respectively) than the asymptomatic patients (Table 1). These variables (p ≤ 0.1) were subsequently entered into a multiple logistic regression model to determine the risk factors for symptomatic UIA. The results showed that in these variables the NLR (OR: 1.468, 95% CI 1.092–1.975, p = 0.011) and size (OR:1.125, 95% CI 1.020–1.241, p = 0.018) were independently associated with symptomatic UIA (Table 2).

Table 2 Multiple logistic regression analysis for symptomatic UIA
Full size table

Furthermore, the optimal cutoff value of NLR to differentiate symptomatic UIA from asymptomatic UIA was 2.38 on ROC curve analysis, and the area under the curve was 0.584 (Fig. 1). Using a cutoff value of 2.38 for NLR, the sensitivity and specificity were 0.389 and 0.781, respectively. In the subgroup with saccular UIAs smaller than 7 mm, the LMR (OR:0.759, 95% CI 0.609–0.947, p = 0.014) was independently associated with symptomatic UIAs in these variables (Tables 3 and 4).

Fig. 1
figure 1

Receiver operating characteristic curve of NLR to differentiate symptomatic UIA, the area under the curve was 0.584, the cutoff value of NLR was 2.38

Full size image
Table 3 Characteristics of aneurysm and laboratory parameter in symptomatic and asymptomatic patients of saccular UIA smaller than 7 mm
Full size table
Table 4 Multiple logistic regression analysis for symptomatic patients with saccular UIA smaller than 7 mm
Full size table

Discussion

To the best of our knowledge, this is the first study investigating the relationship of circulating inflammatory indicators between symptomatic saccular UIA and asymptomatic UIA. Our data confirmed that in saccular UIA patients, the elevation of the baseline NLR was associated with symptomatic and an independent risk factor for symptomatic saccular UIA. On ROC curve analysis, the optimal cutoff value of NLR to differentiate symptomatic UIAs from asymptomatic was 2.38. Moreover, in saccular UIAs smaller than 7 mm, the LMR was the only independent risk factor of symptomatic UIA.

Recently, neuroinflammation has drawn increasing attention, and numerous studies have confirmed that inflammation play critical roles in the pathogenesis and progression of UIAs [2, 3]. Lymphocytes, neutrophils, and monocytes are traditional inflammatory cells, and it was reported that lymphocytes have neuroprotective effects and could improve neurological function [23]. Neutrophils played a key role in the inflammatory mechanisms seen in sarcopenia, which was independently associated with the mRS score at 6 months of patients with subarachnoid hemorrhage treated by endovascular coiling [24]. NLR, LMR and SII, which provide a simple way to assess the inflammatory status, are novel and inexpensive inflammation markers that have been widely used as inflammation indicators in recent years. It was showed that the elevated NLR and SII levels, and the decreased LMR level were more common in acute and chronic inflammatory diseases, immune diseases and cancers. Moreover, these conditions were also observed in acute coronary heart disease [25], heart failure [26], and acute ischemic brain stroke [27, 28]. In addition, several previous literatures reported that NLR, LMR and SII were crucial blood inflammatory indicators in aneurysmal SAH [29,30,31]. Previous studies on NLR, LMR and SII in intracranial aneurysms were inadequate, especially in UIA.

Until now, no studies have reported the clinical value of NLR in symptomatic UIAs. The present study showed that elevation of the baseline NLR was associated with symptomatic saccular UIA. Moreover, NLR was an independent risk factor for symptomatic UIA, indicating an increased level of inflammation in symptomatic UIA patients than in asymptomatic patients. A previous literature reported that high level of NLR showed significant relationship with the size of UIAs, and an elevated NLR may be a clinical feature before the aneurysm rupture [32]. We also showed that aneurysm size was an independent risk factor of symptomatic UIA, indicating that it was unstable, similar to previous studies.

Moreover, we also showed that the optimal cutoff value of NLR to differentiate symptomatic UIA from asymptomatic was 2.38, indicating that NLR ≥ 2.38 might identify unstable saccular UIAs. In addition, we also found that LMR was significantly associated with symptomatic UIAs smaller than 7 mm, indicating that circulating inflammation of patients with small aneurysm might also change.

However, this study has several limitations. First, it was a retrospective study with case selection bias. Second, the number of patients in this study was relatively small, and the results showed that not all inflammatory indicators were significantly higher in the symptomatic UIA group compared to the asymptomatic group, in addition, we did not test and analyze CRP or other inflammatory markers in patients at admission. Thirdly, although we excluded definite infection at admission, our assessment of infection may have been inadequate. Fourth, peripheral blood NLR, LMR and SII may be affected by concomitant diseases, such as hypertension and diabetes mellitus, which might have biased the results. However, this study included NLR in the multifactorial regression analysis, which was found to be an independent risk factor, so the bias may be small. Fifth, inflammatory features in peripheral blood do not directly reflect inflammatory infiltration of the IA wall, we intend to further elucidate its significance in conjunction with pathological studies. Finally, no follow-up study was performed to clarify that UIA with high baseline NLR had a higher rate of aneurysm progression. A follow-up study is needed for confirmation.

Conclusions

NLR was an independent predictor of symptomatic UIA, and its increase may correlate with a high rupture risk of saccular UIA. Symptomatic UIA patients showed high levels of inflammatory indicators, which provided certain hematology evidence that inflammation plays an important role in the formation and progression of UIAs.

Availability of data and materials

The data sets in this study are available from the corresponding author on reasonable request.

Abbreviations

UIA:

Unruptured intracranial aneurysms

SAH:

Spontaneous subarachnoid hemorrhage

AWE:

Aneurysm wall enhancement

HR-VWI:

High-resolution vessel wall imaging

WBC:

White blood cell

NEUT:

Neutral counts

LYM:

Lymphocyte counts

MONO:

Monocyte counts

PLT:

Platelet counts

SII:

Systemic immune-inflammation index

NLR:

Neutrophil-to-lymphocyte ratio

LMR:

Lymphocyte-to-monocyte ratio

ROC:

Receiver operating characteristic

References

  1. Thompson BG, Brown RD Jr, Amin-Hanjani S, Broderick JP, Cockroft KM, Connolly ES Jr, et al. Guidelines for the management of patients with unruptured intracranial aneurysms: a guideline for healthcare professionals from the American heart association/American stroke association. Stroke. 2015;46(8):2368–400.

    Article  PubMed  Google Scholar 

  2. Rodemerk J, Junker A, Chen B, Pierscianek D, Dammann P, Darkwah Oppong M, et al. Pathophysiology of intracranial aneurysms: COX-2 expression, iron deposition in aneurysm wall, and correlation with magnetic resonance imaging. Stroke. 2020;51(8):2505–13.

    Article  CAS  PubMed  Google Scholar 

  3. Liu Q, Zhang Y, Yang J, Yang Y, Li M, Chen S, et al. The relationship of morphological-hemodynamic characteristics, inflammation, and remodeling of aneurysm wall in unruptured intracranial aneurysms. Transl Stroke Res. 2022;13(1):88–99.

    Article  PubMed  Google Scholar 

  4. Signorelli F, Sela S, Gesualdo L, Chevrel S, Tollet F, Pailler-Mattei C, et al. Hemodynamic stress, inflammation, and intracranial aneurysm development and rupture: a systematic review. World Neurosurg. 2018;115:234–44.

    Article  PubMed  Google Scholar 

  5. Frösen J, Cebral J, Robertson AM, Aoki T. Flow-induced, inflammation-mediated arterial wall remodeling in the formation and progression of intracranial aneurysms. Neurosurg Focus. 2019;47(1):E21.

    Article  PubMed  PubMed Central  Google Scholar 

  6. Huuska N, Netti E, Tulamo R, Lehti S, Jahromi BR, Kovanen PT, et al. Serum amyloid A is present in human saccular intracranial aneurysm walls and associates with aneurysm rupture. J Neuropathol Exp Neurol. 2021;80(10):966–74.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Tutino VM, Zebraski HR, Rajabzadeh-Oghaz H, Waqas M, Jarvis JN, Bach K, et al. Identification of circulating gene expression signatures of intracranial aneurysm in peripheral blood mononuclear cells. Diagnostics (Basel). 2021;11(6):1092.

    Article  CAS  PubMed  Google Scholar 

  8. Wan Z, Meng H, Xu N, Liu T, Chen Z, Sun Y, et al. Clinical characteristics associated with sentinel headache in patients with unruptured intracranial aneurysms. Interv Neuroradiol. 2021;27(4):497–502.

    Article  PubMed  Google Scholar 

  9. Fu Q, Wang Y, Zhang Y, Zhang Y, Guo X, Xu H, et al. Qualitative and quantitative wall enhancement on magnetic resonance imaging is associated with symptoms of unruptured intracranial aneurysms. Stroke. 2021;52(1):213–22.

    Article  PubMed  Google Scholar 

  10. Zhong W, Du Y, Guo Q, Tan X, Li T, Chen C, et al. The clinical and morphologic features related to aneurysm wall enhancement and enhancement pattern in patients with anterior circulation aneurysms. World Neurosurg. 2020;134:e649–56.

    Article  PubMed  Google Scholar 

  11. Wang GX, Gong MF, Zhang D, Lei S, Yin JB, Gong ZL, et al. Wall enhancement ratio determined by vessel wall MRI associated with symptomatic intracranial aneurysms. Eur J Radiol. 2019;112:88–92.

    Article  PubMed  Google Scholar 

  12. Fu Q, Guan S, Liu C, Wang K, Cheng J. Clinical significance of circumferential aneurysmal wall enhancement in symptomatic patients with unruptured intracranial aneurysms: a high-resolution MRI study. Clin Neuroradiol. 2018;28(4):509–14.

    Article  PubMed  Google Scholar 

  13. Zhu C, Wang X, Eisenmenger L, Shi Z, Degnan A, Tian B, et al. Wall enhancement on black-blood MRI is independently associated with symptomatic status of unruptured intracranial saccular aneurysm. Eur Radiol. 2020;30(12):6413–20.

    Article  PubMed  Google Scholar 

  14. Hu P, Yang Q, Wang DD, Guan SC, Zhang HQ. Wall enhancement on high-resolution magnetic resonance imaging may predict an unsteady state of an intracranial saccular aneurysm. Neuroradiology. 2016;58(10):979–85.

    Article  PubMed  Google Scholar 

  15. Larsen N, von der Brelie C, Trick D, Riedel CH, Lindner T, Madjidyar J, et al. Vessel wall enhancement in unruptured intracranial aneurysms: an indicator for higher risk of rupture? High-resolution MR imaging and correlated histologic findings. AJNR Am J Neuroradiol. 2018;39(9):1617–21.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Shimonaga K, Matsushige T, Ishii D, Sakamoto S, Hosogai M, Kawasumi T, et al. Clinicopathological insights from vessel wall imaging of unruptured intracranial aneurysms. Stroke. 2018;49(10):2516–9.

    Article  PubMed  Google Scholar 

  17. Quan K, Song J, Yang Z, Wang D, An Q, Huang L, et al. Validation of wall enhancement as a new imaging biomarker of unruptured cerebral aneurysm. Stroke. 2019;50(6):1570–3.

    Article  PubMed  Google Scholar 

  18. Zhong W, Su W, Li T, Tan X, Chen C, Wang Q, et al. Aneurysm wall enhancement in unruptured intracranial aneurysms: a histopathological evaluation. J Am Heart Assoc. 2021;10(2):e018633.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Bae H, Suh SI, Yoon WK, Roh H, Kim C, Kwon TH. Correlation of aneurysmal wall enhancement of unruptured intracranial aneurysms on high-resolution vessel-wall imaging with clinical indices and surgical findings. Neurosurgery. 2021;89(3):420–7.

    Article  PubMed  Google Scholar 

  20. Wu XB, Zhong JL, Wang SW, Su Y, Chen PS, Li ZJ, et al. Neutrophil-to-lymphocyte ratio is associated with circumferential wall enhancement of unruptured intracranial aneurysm. Front Neurol. 2022;13:879882.

    Article  PubMed  PubMed Central  Google Scholar 

  21. Gilard V, Grangeon L, Guegan-Massardier E, Sallansonnet-Froment M, Maltête D, Derrey S, et al. Headache changes prior to aneurysmal rupture: a symptom of unruptured aneurysm? Neurochirurgie. 2016;62:241–4.

    Article  CAS  PubMed  Google Scholar 

  22. Cianfoni A, Pravatà E, De Blasi R, Tschuor CS, Bonaldi G. Clinical presentation of cerebral aneurysms. Eur J Radiol. 2013;82:1618–22.

    Article  PubMed  Google Scholar 

  23. Macrez R, Ali C, Toutirais O, Le Mauff B, Defer G, Dirnagl U, et al. Stroke and the immune system: from pathophysiology to new therapeutic strategies. Lancet Neurol. 2011;10(5):471–80.

    Article  CAS  PubMed  Google Scholar 

  24. Katsuki M, Suzuki Y, Kunitoki K, Sato Y, Sasaki K, Mashiyama S, et al. Temporal muscle as an indicator of sarcopenia is independently associated with hunt and kosnik grade on admission and the modified rankin scale score at 6 months of patients with subarachnoid hemorrhage treated by endovascular coiling. World Neurosurg. 2020;137:e526–34.

    Article  PubMed  Google Scholar 

  25. Angkananard T, Anothaisintawee T, McEvoy M, Attia J, Thakkinstian A. Neutrophil lymphocyte ratio and cardiovascular disease risk: a systematic review and meta-analysis. Biomed Res Int. 2018;2018:2703518.

    Article  PubMed  PubMed Central  Google Scholar 

  26. Delcea C, Buzea CA, Vijan A, Draghici A, Stoichitoiu LE, Dan GA. Comparative role of hematological indices for the assessment of in-hospital outcome of heart failure patients. Scand Cardiovasc J. 2021;55(4):227–36.

    Article  CAS  PubMed  Google Scholar 

  27. Sharma D, Spring KJ, Bhaskar SMM. Neutrophil-lymphocyte ratio in acute ischemic stroke: immunopathology, management, and prognosis. Acta Neurol Scand. 2021;144(5):486–99.

    Article  PubMed  Google Scholar 

  28. Lattanzi S, Norata D, Divani AA, Di Napoli M, Broggi S, Rocchi C, et al. Systemic inflammatory response index and futile recanalization in patients with ischemic stroke undergoing endovascular treatment. Brain Sci. 2021;11(9):1164.

    Article  PubMed  PubMed Central  Google Scholar 

  29. Shi M, Yang C, Tang QW, Xiao LF, Chen ZH, Zhao WY. The prognostic value of neutrophil-to-lymphocyte ratio in patients with aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis of observational studies. Front Neurol. 2021;12:745560.

    Article  PubMed  PubMed Central  Google Scholar 

  30. Feghali J, Kim J, Gami A, Rapaport S, Caplan JM, McDougall CG, et al. Monocyte-based inflammatory indices predict outcomes following aneurysmal subarachnoid hemorrhage. Neurosurg Rev. 2021;44(6):3499–507.

    Article  PubMed  Google Scholar 

  31. Chen L, Pandey S, Shen R, Xu Y, Zhang Q. Increased systemic immune-inflammation index is associated with delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage patients. Front Neurol. 2021;12:745175.

    Article  PubMed  PubMed Central  Google Scholar 

  32. Zhang B, Lin L, Yuan F, Song G, Chang Q, Wu Z, et al. Clinical application values of neutrophil-to-lymphocyte ratio in intracranial aneurysms. Aging (Albany NY). 2021;13(4):5250.

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

None.

Funding

The Shenzhen Futian District Public Health Research Project, Grant Number: FTWS2021015; the Shenzhen Science and Technology Research and Development Fund, the Number: JCYJ20190808100813208.

Author information

Author notes

  1. De-Xiang Zheng and Yi-Yang Lv have contributed equally to this work and share first authorship.

Authors and Affiliations

  1. Department of Clinical Laboratory, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China

    De-Xiang Zheng & Cha Chen

  2. The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China

    De-Xiang Zheng & Cha Chen

  3. Department of Blood Transfusion, Nanfang Hospital, Southern Medical University, Guangzhou, China

    Yi-Yang Lv

  4. Department of Epilepsy Center, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China

    Xiao-Jing Zhang

  5. School of Civil Engineering and Transportation, South China University of Technology, Guangzhou, 510640, China

    Jie-Shun Ye

  6. Department of Neurosurgery, The Eighth Affiliated Hospital, Sun Yat-Sen University, Shenzhen, 518033, China

    Jian-Xing Zhang & Bin Luo

  7. Department of Ultrasound, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China

    Dan Yan

Authors
  1. De-Xiang Zheng
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yi-Yang Lv
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Xiao-Jing Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Jie-Shun Ye
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Jian-Xing Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Cha Chen
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Bin Luo
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Dan Yan
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

YD, LB and CC participated in the design of the study. All authors participated in the interpretation and collection of the data. ZDX and LYY wrote the initial manuscript. All authors critically reviewed and edited the manuscript and approved the final version.

Corresponding authors

Correspondence to Cha Chen, Bin Luo or Dan Yan.

Ethics declarations

Ethics approval and consent to participate

The study protocols were approved by the ethics committees of Guangdong Provincial Hospital of Traditional Chinese Medicine. Written informed consent was obtained from all patients participating in the study. All the steps/methods were performed in accordance with the relevant guidelines and regulations.

Consent for publication

Not applicable.

Competing interests

All authors have no competing interests to declare.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zheng, DX., Lv, YY., Zhang, XJ. et al. Neutrophil-to-lymphocyte ratio associated with symptomatic saccular unruptured intracranial aneurysm. Eur J Med Res 29, 40 (2024). https://doi.org/10.1186/s40001-023-01608-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s40001-023-01608-3

Keywords

European Journal of Medical Research

ISSN: 2047-783X

Contact us