Table of Contents Author Guidelines Submit a Manuscript
Neurology Research International
Volume 2018, Article ID 7268924, 6 pages
https://doi.org/10.1155/2018/7268924
Clinical Study

Efficacy of High-Dose and Low-Dose Simvastatin on Vascular Oxidative Stress and Neurological Outcomes in Patient with Acute Ischemic Stroke: A Randomized, Double-Blind, Parallel, Controlled Trial

1Neurology, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand
2Department of Applied Thai Traditional Medicine, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand
3Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand

Correspondence should be addressed to Sombat Muengtaweepongsa; moc.liamtoh@mtabmos

Received 3 January 2018; Revised 26 February 2018; Accepted 13 March 2018; Published 18 April 2018

Academic Editor: Jeff Bronstein

Copyright © 2018 Nattaphol Uransilp et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Backgrounds. Stroke is the leading cause of death and long-term disability. Oxidative stress is elevated during occurrence of acute ischemic stroke (AIS). Soluble LOX-1 (sLOX-1) and NO are used as biomarkers for vascular oxidative stress that can reflect stabilization of atherosclerotic plaque. Previous study showed that simvastatin can reduce oxidative stress and LOX-1 expression. Objectives. To evaluate neurological outcomes and serum sLOX-1 and NO levels in patients with AIS treatment with low dose 10 mg/day and high dose 40 mg/day of simvastatin. Methods. 65 patients with AIS within 24 hours after onset were randomized to treatment with simvastatin 10 mg/day or 40 mg/day for 90 days. Personal data and past history of all patients were recorded at baseline. The blood chemistries were measured by standard laboratory techniques. Serum sLOX-1 and NO levels and neurological outcomes including NIHSS, mRS, and Barthel index were tested at baseline and Day 90 after simvastatin therapy. Results. Baseline characteristics were not significantly different in both groups except history of hypertension. Serum sLOX-1 and NO levels significantly reduce in both groups (sLOX-1 = and  ng/ml; NO = and μmol/l) in 10 mg/day and 40 mg/day simvastatin groups, respectively. Neurological outcomes including NIHSS, mRS, and Barthel index significantly improve in both groups. However, no difference in NO level and neurological outcomes was found at 90 days after treatment as compared between low dose 10 mg/day and high dose 40 mg/day of simvastatin. Conclusion. High-dose simvastatin might be helpful to reduce serum sLOX-1. But no difference in clinical outcomes was found between high- and low-dose simvastatin. Further more intensive clinical trial is needed to confirm the appropriate dosage of simvastatin in patients with acute ischemic stroke. This trial is registered with ClinicalTrials.gov ID: NCT03402204.

1. Introduction

Ischemic stroke is the main etiology of disability in senile population and remains the third most common cause of death in the world [1]. Stroke has been the common cause of mortality in Thailand for decades [24]. The prevalence of stroke is one percent in Thai people aged more than 30 years [5] or 1.88 percent in Thai people aged more than 45 years [6]. Oxidative stress is defined as a disturbance in the prooxidant-antioxidant balance in favor of the prooxidant, leading to potential damage [7]. Oxidative stress is elevated during occurrence of acute ischemic stroke (AIS) [8, 9].

Previous study found that oxidized-low density lipoprotein (ox-LDL) and oxidative stress induce production of lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) and cleavage some extracellular parts of LOX-1 into blood circulation, and it is called soluble LOX-1 (sLOX-1) [10]. The sLOX-1 is used for biomarker in patients with myocardial infarction (MI), coronary artery diseases (CAD), metabolic syndrome, or others [11, 12]. It is known that oxidized-LDL can lead to plaque instability by increasing vascular oxidative stress and by upregulation of matrix metalloproteinases (MMPs).

During 24 hours after onset of ischemic stroke, nitric oxide (NO) is mainly produced by activation of both inducible nitric oxide synthase (iNOS) and neuronal nitric oxide synthase (nNOS). These two subtypes of NO are considered as neurotoxic agents and supposed to become lower at 3 months after onset. In contrast, NO created by endothelial nitric oxide synthase (eNOS) demonstrates neuroprotective effect [13]. However, eNOS produces small amount of NO at the ultraearly stage of ischemic stroke. Simvastatin shows gainful effect for ischemic stroke by upregulation of eNOS activity [14].

Simvastatin is a cholesterol-lowering medication which acts by inhibiting hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase, hence used for the primary and secondary prevention of ischemic stroke. Simvastatin can inhibit activation of extracellular regulated kinase (ERK) 1/2 and proliferation of rat vascular smooth muscle cells [15], attenuation of inflammation, oxidative stress and plaque stabilization, and plaque thickness in type 2 diabetes patients [16]. Simvastatin can reduce oxidative stress through inhibiting nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and reducing angiotensin type 1 (AT1) receptor. Therefore, overall effect of simvastatin beyond lowering cholesterol includes improving endothelial function, modulating thrombogenesis, attenuating inflammatory, and oxidative stress damage, and facilitating angiogenesis [17].

This study aims to investigate outcomes of simvastatin 10 mg/day and 40 mg/day on vascular oxidative stress and neurological outcomes in patients with acute ischemic stroke. We expect that the results of our study might have clinical implications for ischemic stroke prevention in future.

2. Material and Methods

2.1. Study Population

We recruited patients with acute ischemic stroke received at Thammasat University Hospital between April 2014 and December 2015. Patients who met the following inclusion criteria were eligible: 18 to 85 years old; diagnosis of an acute ischemic stroke; and ability to start the study drug within 24 hours after symptom onset. Patients were excluded if they had any of the following: contraindication to simvastatin; prestroke mRS score more than 1; conscious level > 2 scores on question 2 of NIHSS; hematocrit less than 0.25; blood sugar (BS) less than 60 mg/dl or more than 200 ml/dl or between 200 and 300 mg/dl and treated with diabetes drug until the BS levels are less than 200 mg/dl; acute myocardial infarction (AMI) or coronary heart disease (CHD) within 3 weeks; patient who receives lower-lipid level drug, that is, ezetimibe, fenofibrate, gemfibrozil, and niacin, or statin drugs, that is, atorvastatin and pitavastatin, and increasing liver enzyme level or liver disease. The study was registered in ClinicalTrials.gov. The clinical study registration number is NCT03402204.

2.2. Study Design

Patients with acute ischemic stroke were divided into 2 groups (simvastatin 10 mg/day and 40 mg/day). Personal and past medical history were recorded after the patients signed informed consent. Blood samples were collected from patients for measuring biomarkers in serum related to vascular oxidative stress, that is, sLOX-1 and NO, and neurological examination was done, that is, NIHSS, mRS, and Barthel’s index scale at Day 0 and Day 90.

2.3. Blood Chemical Analysis

Peripheral venous blood samples of all 65 patients with acute ischemic stroke were obtained not later than 24 hours after onset. The sample was centrifuged 3,000 rpm at 4°C for 15 minutes. Serum samples were frozen at −80°C until analysis. Serum blood sugar, cholesterol, triglycerides, high density lipoprotein cholesterol (HDL-c), and low density lipoprotein cholesterol (LDL-c) were measured by standard laboratory techniques of Thammasat University Hospital. Serum sLOX-1 and NO levels were determined using commercially available enzyme-linked immunosorbent assay (ELISA) kits (R&D systems, MN, USA).

2.4. Ethical Consideration

The clinical study protocol was submitted to Ethical Committee of Faculty of Medicine, Thammasat University (number 1) for approval before conducting experiments. The number of approved protocol is MTU-EC-4-019/58.

2.5. Data Analysis

SPSS version 16.0 for Windows (Chicago, IL, USA) was used for statistical analysis. All data were presented as mean ± standard deviation (SD). The possible statistical differences among groups were tested using Mann–Whitney test or Chi square test. The possible statistical difference among persons at Day 0 and Day 90 was tested using Wilcoxon test. A probability value of less than 0.05 was considered to be statistically significant.

3. Results

3.1. Baseline Clinical Characteristics

34 patients were treated with simvastatin 10 mg/day and 31 patients were treated with simvastatin 40 mg/day during the study period. Baseline characteristics were shown in Table 1. There were no significant differences in age, systolic or diastolic blood pressure, blood sugar, lipid profile, NIHSS score, and treatment with IV rtPA between the two groups but there was significant difference in medical history of hypertension.

Table 1: Baseline characteristics of patients with acute ischemic stroke receiving simvastatin therapy.

As Table 2 showed there is no significant difference in serum sLOX-1 and NO level at baseline in patients with AIS between 2 groups.

Table 2: Serum sLOX-1 and NO levels in patients with acute ischemic stroke at baseline.
3.2. Association of Serum sLOX-1, NO Levels, and Neurological Outcomes after Simvastatin Therapy

After 90 days of simvastatin treatment, serum sLOX-1 level was significantly reduced in simvastatin 40 mg/day group () but there was no difference in NO level as compared between simvastatin 10 mg/day and simvastatin 40 mg/day group (Table 3 and Figure 1). When compared between Day 0 and Day 90 within each group (Table 4), both sLOX-1 and NO were significantly declined at Day 90 in both groups. NIHSS, mRS, and Barthel index were improved at Day 90 in both groups (Table 5, all ). However, there was no difference in NIHSS, mRS, and Barthel index at Day 90 as compared between simvastatin 10 mg/day and simvastatin 40 mg/day group (Table 6).

Table 3: Serum sLOX-1 and NO levels in patient with acute ischemic stroke received simvastatin therapy for 90 days.
Table 4: Compare serum sLOX-1 and NO levels in patient with acute ischemic stroke at 0 days and 90 days after simvastatin therapy.
Table 5: Compare neurological outcome in patient with acute ischemic stroke 0 days and 90 days after simvastatin therapy.
Table 6: Compare neurological outcome in patient with acute ischemic stroke at 90 days after simvastatin therapy.
Figure 1: Serum sLOX-1 (a) and NO (b) levels of patients with acute ischemic stroke that compare simvastatin 10 mg/day and 40 mg/day at Day 90 after simvastatin treatment. .

4. Discussion

Acute ischemic stroke patients receiving simvastatin 10 and 40 mg/day for 90 days significantly decreased serum sLOX-1 and NO levels and improved neurological outcome. Simvastatin 40 mg/day group significantly reduced sLOX-1 level compared to simvastatin 10 mg/day at 90 days after treatment. According to the previous study of statin in patients with ischemic stroke, age did not affect any outcomes [18]. Patients aged between 18 and 85 years were included in our study.

The involvement of LOX-1 is a factor that affects development of atherosclerosis from several factors; for example, dyslipidemia played the major role in the upregulation of LOX-1 through ox-LDL stimulation [19], hyperglycemia increased LOX-1 upregulation in human endothelial cells via activation of reactive oxygen species (ROS) [20], and hypertension upregulated the expression of LOX-1 by induction of angiotensin II [21]. Previous studies have also found that sLOX-1 are significantly increased in obesity [22] and type 2 DM. The activation of LOX-1 affects atherosclerotic plaque formation and progression through dysfunction of endothelial cells [23], apoptosis of vascular smooth muscle cells [24], accumulation of lipids in macrophages [25], and production of matrix metalloproteinases [26]. Schwarz et al. reported that LOX-1 expression was induced 10-fold at ischemic core sites during experimental stroke [27]. Thus, activation of LOX-1 might facilitate the pathophysiological conditions leading to stroke.

The major findings of this study show that simvastatin significantly reduces serum sLOX-1 levels after 90 days of treatment. But only higher dose of simvastatin (40 mg/day) can decrease serum sLOX-1 at Day 90 of treatment. This finding reflects higher doses of simvastatin may be more useful in improving plaque stability and reduce risk for recurrent ischemic stroke than lower doses of simvastatin.

As mentioned above, serum NO demonstrates not only pros but also cons effects on patients with ischemic stroke. NO produced by iNOS and nNOS is among the cons while NO produced by eNOS is among the pros. From temporal ischemic stroke in our study, majority of NO is produced by iNOS and nNOS [13]. Decrement of NO at 90 days after onset should be a natural course of ischemic stroke. Simvastatin may upregulate eNOS leading to rising NO. However, eNOS usually produces a small amount of NO. Simvastatin may not be able to affect NO level in our study.

The mechanisms by which statins provide benefit to patients with acute ischemic stroke remain unclear and are likely multifactorial. Previous study indicates that statin has multiple effect beyond cholesterol lowering including improving endothelial function, modulating thrombogenesis, attenuating inflammatory and oxidative stress damage, and facilitating angiogenesis [17]. In animal model of stroke, statin shows benefits to reduction in infarct size [28] and improves neurological function and cerebral blood flow [29]. Recent study shows patients who take statin have 2.63 times greater probability of discharge home compared to untreated patients [30]. Our results are in agreement with previous studies that have shown improvement in functional outcome in stroke patients treated with statins.

There are several limitations to this study. First, this study was cross-sectional, thereby allowing the determination of associations but not formulation of risk predictions. In addition, the study populations were relatively small. Therefore, our findings need further investigation in prospective studies with larger sample size. Last, sLOX-1 and NO levels might be higher or lower in patients with ICAS than in general population. Therefore, a normal control group should be included in future studies to evaluate the degree of impact of the presence and severity of acute ischemic stroke. The low proportion of patients with neurological progression could be secondary to a selection bias because of the admission of patients with less severe symptoms. Last, neurological improvement in stroke patient could be from other factors than statin: age, NIHSS scale on admission, HbA1c level, and location of stroke [31].

5. Conclusion

Our study showed that high-dose simvastatin significantly reduced serum sLOX-1. However, no difference in clinical outcome between high-dose and low-dose simvastatin was found at 90 days after treatment. Further more intensive clinical trial is needed to confirm the appropriate dosage of simvastatin in patients with acute ischemic stroke.

Abbreviations

SBP:Systolic blood pressure
DBP:Diastolic blood pressure
rtPA:Recombinant tissue plasminogen activator
IV:Intravenous route
AIS:Acute ischemic stroke
LOX-1:Lectin-like oxidized low density lipoprotein receptor-1
sLOX-1:Soluble LOX-1
MI:Myocardial infarction
CAD:Coronary artery diseases
MMPs:Matrix metalloproteinases
iNOS:Inducible nitric oxide synthase
NO:Nitric oxide
HMG-CoA:Hydroxymethylglutaryl-coenzyme A
ERK:Extracellular regulated kinase
NADPH:Nicotinamide adenine dinucleotide phosphate
:Angiotensin type 1
BS:Blood sugar
CHD:Coronary heart disease
HDL-c:High density lipoprotein cholesterol
LDL-c:Low density lipoprotein cholesterol
ELISA:Enzyme-linked immunosorbent assay
NIHSS:National Institutes of Health Stroke Scale
mRS:Modified Rankin Scale.

Disclosure

The manuscript was presented at World Congress of Neurology (WCN 2017): https://www.sciencedirect.com/science/article/pii/S0022510X17308365.

Conflicts of Interest

The authors declare that there are no conflicts of interest regarding the publication of this paper.

Acknowledgments

This work was supported by the Center of Excellence in Stroke, Thammasat University Hospital, Thammasat University. Finally, the authors thank all patients in the study and staffs of stroke unit in Thammasat University Hospital.

References

  1. A. D. Lopez, C. D. Mathers, M. Ezzati, D. T. Jamison, and C. J. Murray, “Global and regional burden of disease and risk factors, 2001: systematic analysis of population health data,” The Lancet, vol. 367, no. 9524, pp. 1747–1757, 2006. View at Publisher · View at Google Scholar · View at Scopus
  2. Stroke epidemiological data of nine Asian countries, “Asian Acute Stroke Advisory Panel (AASAP),” J Med Assoc Thai, vol. 83, no. 1, pp. 1–7, 2000. View at Google Scholar
  3. N. Poungvarin, “Burden of stroke in Thailand,” International Journal of Stroke, vol. 2, no. 2, pp. 127-128, 2007. View at Publisher · View at Google Scholar · View at Scopus
  4. S. Hanchaiphiboolkul, N. Poungvarin, S. Nidhinandana et al., “Prevalence of stroke and stroke risk factors in thailand: Thai epidemiologic stroke (TES) study,” Journal of the Medical Association of Thailand, vol. 94, no. 4, pp. 427–436, 2011. View at Google Scholar · View at Scopus
  5. S. Palangrit and S. Muengtaweepongsa, “Risk factors of stroke in Pathumthani Province, Thailand,” Journal of the Medical Association of Thailand, vol. 98, no. 7, pp. 649–655, 2015. View at Google Scholar · View at Scopus
  6. N. C. Suwanwela, “Stroke epidemiology in Thailand,” Journal of Stroke, vol. 16, no. 1, pp. 1–7, 2014. View at Publisher · View at Google Scholar
  7. H. Sies, “Oxidative stress: oxidants and antioxidants,” Experimental Physiology, vol. 82, no. 2, pp. 291–295, 1997. View at Publisher · View at Google Scholar · View at Scopus
  8. P. Chaiyawatthanananthn, K. Suwanprasert, and S. Muengtaweepongsa, “Differentiation of serum sLOX-1 and NO levels in acute ischemic stroke patients with internal carotid artery stenosis and those without internal carotid artery stenosis,” Journal of the Medical Association of Thailand, vol. 99, pp. S48–S53, 2016. View at Google Scholar · View at Scopus
  9. İ. Atik, N. Kozacı, İ. Beydilli, M. Avcı, H. Ellidağ, and M. Keşaplı, “Investigation of oxidant and antioxidant levels in patients with acute stroke in the emergency service,” The American Journal of Emergency Medicine, vol. 34, no. 12, pp. 2379–2383, 2016. View at Publisher · View at Google Scholar · View at Scopus
  10. T. E. Brinkley, N. Kume, H. Mitsuoka et al., “Variation in the human lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) gene is associated with plasma soluble LOX-1 levels,” Experimental Physiology, vol. 93, no. 9, pp. 1085–1090, 2008. View at Publisher · View at Google Scholar · View at Scopus
  11. X. Li, P. Jin, J. Xue et al., “Role of sLOX-1 in intracranial artery stenosis and in predicting long-term prognosis of acute ischemic stroke,” Brain and Behavior, vol. 8, no. 1, p. e00879, 2018. View at Publisher · View at Google Scholar
  12. I. M. Caglar, C. Ozde, I. Biyik et al., “Association between soluble lectin-like oxidized low-density lipoprotein receptor 1 levels and coronary slow flow phenomenon,” Archives of Medical Science, vol. 12, no. 1, pp. 31–37, 2016. View at Publisher · View at Google Scholar · View at Scopus
  13. Z.-Q. Chen, R.-T. Mou, D.-X. Feng, Z. Wang, and G. Chen, “The role of nitric oxide in stroke,” Medical Gas Research, vol. 7, no. 3, pp. 194–203, 2017. View at Publisher · View at Google Scholar · View at Scopus
  14. M. Sabri, J. Ai, P. A. Marsden, and R. L. Macdonald, “Simvastatin re-couples dysfunctional endothelial nitric oxide synthase in experimental subarachnoid hemorrhage,” PLoS ONE, vol. 6, no. 2, Article ID e17062, 2011. View at Publisher · View at Google Scholar · View at Scopus
  15. Z. Zhang, M. Zhang, Y. Li et al., “Simvastatin inhibits the additive activation of ERK1/2 and proliferation of rat vascular smooth muscle cells induced by combined mechanical stress and oxLDL through LOX-1 pathway,” Cellular Signalling, vol. 25, no. 1, pp. 332–340, 2013. View at Publisher · View at Google Scholar · View at Scopus
  16. C. Cuccurullo, A. Iezzi, M. L. Fazia et al., “Suppression of rage as a basis of simvastatin-dependent plaque stabilization in type 2 diabetes,” Arteriosclerosis, Thrombosis, and Vascular Biology, vol. 26, no. 12, pp. 2716–2723, 2006. View at Publisher · View at Google Scholar · View at Scopus
  17. J. Zhao, X. Zhang, L. Dong, Y. Wen, and L. Cui, “The many roles of statins in ischemic stroke,” Current Neuropharmacology, vol. 12, no. 6, pp. 564–574, 2014. View at Publisher · View at Google Scholar · View at Scopus
  18. Investigators TSPbARiCL, “High-Dose Atorvastatin after Stroke or Transient Ischemic Attack,” New England Journal of Medicine, vol. 355, no. 6, pp. 549–959, 2006. View at Google Scholar
  19. H. Chen, D. Li, T. Sawamura, K. Inoue, and J. L. Mehta, “Upregulation of LOX-1 expression in aorta of hypercholesterolemic rabbits: Modulation by losartan,” Biochemical and Biophysical Research Communications, vol. 276, no. 3, pp. 1100–1104, 2000. View at Publisher · View at Google Scholar · View at Scopus
  20. A. Taye, A. H. Saad, A. H. Kumar, and H. Morawietz, “Effect of apocynin on NADPH oxidase-mediated oxidative stress-LOX-1-eNOS pathway in human endothelial cells exposed to high glucose,” European Journal of Pharmacology, vol. 627, no. 1–3, pp. 42–48, 2010. View at Publisher · View at Google Scholar · View at Scopus
  21. C. Hu, A. Dandapat, L. Sun et al., “Modulation of angiotensin II-mediated hypertension and cardiac remodeling by lectin-like oxidized low-density lipoprotein receptor-1 deletion,” Hypertension, vol. 52, no. 3, pp. 556–562, 2008. View at Publisher · View at Google Scholar · View at Scopus
  22. T. E. Brinkley, N. Kume, H. Mitsuoka, D. A. Phares, and J. M. Hagberg, “Elevated soluble lectin-like oxidized LDL receptor-1 (sLOX-1) levels in obese postmenopausal women,” Obesity, vol. 16, no. 6, pp. 1454–1456, 2008. View at Publisher · View at Google Scholar · View at Scopus
  23. D. Li and J. L. Mehta, “Antisense to LOX-1 inhibits oxidized LDL-mediated upregulation of monocyte chemoattractant protein-1 and monocyte adhesion to human coronary artery endothelial cells,” Circulation, vol. 101, no. 25, pp. 2889–2895, 2000. View at Publisher · View at Google Scholar · View at Scopus
  24. N. Kume and T. Kita, “Apoptosis of Vascular Cells by Oxidized LDL: Involvement of Caspases and LOX-1 and Its Implication in Atherosclerotic Plaque Rupture,” Circulation Research, vol. 94, no. 3, pp. 269-270, 2004. View at Publisher · View at Google Scholar · View at Scopus
  25. I. V. Smirnova, M. Kajstura, T. Sawamura, and M. S. Goligorsky, “Asymmetric dimethylarginine upregulates LOX-1 in activated macrophages: role in foam cell formation,” American Journal of Physiology-Heart and Circulatory Physiology, vol. 287, no. 2, pp. H782–H790, 2004. View at Publisher · View at Google Scholar · View at Scopus
  26. D. Li, L. Liu, H. Chen, T. Sawamura, S. Ranganathan, and J. L. Mehta, “LOX-1 mediates oxidized low-density lipoprotein-induced expression of matrix metalloproteinases in human coronary artery endothelial cells,” Circulation, vol. 107, no. 4, pp. 612–617, 2003. View at Publisher · View at Google Scholar · View at Scopus
  27. D. A. Schwarz, G. Barry, K. B. Mackay et al., “Identification of differentially expressed genes induced by transient ischemic stroke,” Brain Research, vol. 101, no. 1-2, pp. 12–22, 2002. View at Publisher · View at Google Scholar · View at Scopus
  28. M. Endres, U. Laufs, Z. Huang et al., “Stroke protection by 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitors mediated by endothelial nitric oxide synthase,” Proceedings of the National Acadamy of Sciences of the United States of America, vol. 95, no. 15, pp. 8880–8885, 1998. View at Publisher · View at Google Scholar · View at Scopus
  29. J. Chen, Z. G. Zhang, Y. Li et al., “Statins induce angiogenesis, neurogenesis, and synaptogenesis after stroke,” Annals of Neurology, vol. 53, no. 6, pp. 743–751, 2003. View at Publisher · View at Google Scholar · View at Scopus
  30. M. Moonis, R. Kumar, N. Henninger, K. Kane, and M. Fisher, “Pre and post-stroke use of statins improves stroke outcome,” Indian Journal of Community Medicine, vol. 39, no. 4, pp. 214–217, 2014. View at Publisher · View at Google Scholar · View at Scopus
  31. T. Kuwashiro, H. Sugimori, T. Ago, J. Kuroda, M. Kamouchi, and T. Kitazono, “The impact of predisposing factors on long-term outcome after stroke in diabetic patients: the Fukuoka Stroke Registry,” European Journal of Neurology, vol. 20, no. 6, pp. 921–927, 2013. View at Publisher · View at Google Scholar · View at Scopus