田中 亮太

BACKGROUND: Cerebral microbleeds (CMBs) are associated with the risk of intracerebral hemorrhage in stroke patients with atrial fibrillation (AF). We investigated the association between CMBs and chronic kidney disease (CKD) in patients with acute ischemic stroke and AF. METHODS: We retrospectively examined consecutive patients with acute ischemic stroke and AF who underwent brain gradient-echo T2*-weighted magnetic resonance imaging. The number and distribution (lobar, deep or infratentorial, and mixed) of CMBs were assessed. Kidney function was assessed according to the estimated glomerular filtration rate (eGFR), which was calculated using a modified version of the Modification of Diet in Renal Disease equation. RESULTS: Of the 357 included patients, 105 (29.4%) had CMBs. CKD (eGFR < 60 mL/min/1.73 m2) was found in 131 (36.7%) patients. Patients with CKD showed a higher prevalence of any form of CMB (41.2% versus 22.6%, P < .001), deep or infratentorial CMBs (19.9% versus 9.3%, P < .01), and mixed CMBs (14.5% versus 5.3%, P < .01) than those without CKD. After adjusting for age and other confounding factors, CKD was found to be independently associated with the presence of any form of CMB (odds ratio 1.89, P = .02) and mixed CMBs (odds ratio 3.10, P < .01). Moreover, moderate to severe CKD (eGFR < 45 mL/min/1.73 m2) was independently associated with the presence of multiple CMBs (odds ratio 2.31, P = .04). CONCLUSIONS: CMBs and CKD are common in acute ischemic stroke patients with AF, and CKD may be a risk factor for CMBs. Further longitudinal studies are needed to evaluate whether maintaining kidney function can prevent the development of CMBs.

AIMS: The ratio of eicosapentaenoic acid (EPA) to arachidonic acid (AA) is related to major adverse events and death in cardiovascular diseases. The association between long-term prognosis of ischemic stroke and EPA/AA ratio has not been clarified. METHODS: Acute ischemic stroke patients who had undergone blood examinations for polyunsaturated fatty acids were enrolled. Major cardiovascular events, including recurrence of ischemic stroke, occurrence of cardiovascular and peripheral artery diseases and hemorrhagic stroke, and death, were analyzed, retrospectively. Cox proportional hazards regression analysis was used to explore factors, including clinical characteristics, laboratory data including EPA/AA ratio, and treatments associated with major cardiovascular events and death. RESULTS: A total of 269 patients (mean age, 70±13 years; 179 men) were enrolled. During follow-up (mean, 2.3 ±1.0 years), 64 patients exhibited major cardiovascular events and death (annualized rate, 10.5% per person-year). Multivariate Cox analysis revealed that EPA/AA ratio (hazard ratio, 0.26; 95% confidence interval, 0.07- 0.99; p=0.048) and statin therapy (hazard ratio, 0.43; 95% confidence interval, 0.25-0.73; p=0.002) correlated inversely with major cardiovascular events and death. In the Kaplan-Meier analysis, cumulative event-free rates were significantly lower among patients with EPA/AA ratio ＜0.33 and patients without statin therapy (p=0.006). CONCLUSIONS: Low EPA/AA ratio at baseline and treatment without statins could predict mortality, recurrent ischemic stroke, cardiovascular and peripheral artery diseases, and hemorrhagic stroke among patients with acute ischemic stroke. The combination of baseline EPA/AA ratio and statin therapy could be critical in predicting the long-term prognosis of ischemic stroke patients.

Lipopolysaccharide (LPS) is a major component of the outer membrane of Gram-negative bacteria and a potent inflammatory stimulus for the innate immune response via toll-like receptor (TLR) 4 activation. Type 2 diabetes is associated with changes in gut microbiota and impaired intestinal barrier functions, leading to translocation of microbiota-derived LPS into the circulatory system, a condition referred to as metabolic endotoxemia. We investigated the effects of metabolic endotoxemia after experimental stroke with transient middle cerebral artery occlusion (MCAO) in a murine model of type 2 diabetes (db/db) and phenotypically normal littermates (db/+). Compared to db/+ mice, db/db mice exhibited an altered gut microbial composition, increased intestinal permeability, and higher plasma LPS levels. In addition, db/db mice presented increased infarct volumes and higher expression levels of LPS, TLR4, and inflammatory cytokines in the ischemic brain, as well as more severe neurological impairments and reduced survival rates after MCAO. Oral administration of a non-absorbable antibiotic modulated the gut microbiota and improved metabolic endotoxemia and stroke outcomes in db/db mice; these effects were associated with reduction of LPS levels and neuroinflammation in the ischemic brain. These data suggest that targeting metabolic endotoxemia may be a novel potential therapeutic strategy to improve stroke outcomes.

AIM: Aortic arch atherosclerosis, particularly complex aortic arch plaques (CAPs), is an important source of cerebral emboli. CAPs and atrial fibrillation (AF) often co-exist; however, the prevalence and risk of CAPs in acute ischemic stroke patients with AF is unclear. METHODS: In patients with acute ischemic stroke with non-valvular AF admitted to Jichi Medical University Hospital during April 2016 to September 2019, we retrospectively evaluated the presence of CAPs on transesophageal echocardiography (TEE). RESULTS: CAPs were observed in 41 (38.7 %) of 106 patients with non-valvular AF. Older age, diabetes mellitus, chronic kidney disease, low high-density lipoprotein cholesterol (HDL-C) levels, higher levels of glycohemoglobin A1c (HbA1c), higher CHADS2 and CHA2DS2-VASc scores, and intracranial or carotid artery stenosis were more frequently observed in CAPs-positive than in CAPs-negative patients. In multivariable analyses, older age (odds ratio [OR]: 1.2 per year increase; 95% confidence interval [CI]: 1.07-1.24; P＜0.0001), diabetes mellitus (OR: 4.7; 95%CI: 1.27-17.35; P＜0.05), and low HDL-C (OR: 0.95 per 1 mg/dl increase; 95%CI: 0.92-0.99; P ＜0.01) were independent risk factors for CAPs. The prevalence of CAPs was age-dependent, and there was a significantly higher risk in patients aged either 75-84 years or ＞84 years than in those aged ＜65 (OR: 7.6; 95%CI: 1.50-38.62, and OR: 32.1; 95%CI: 5.14-200.11, respectively). CONCLUSIONS: Even in patients with ischemic stroke with non-valvular AF, concomitant CAPs should be considered in older individuals and those who have diabetes or low HDL-C.

Data presented in this article are related to our article entitled "Unilateral posterior reversible encephalopathy syndrome: A case report" [1]. Cases of Posterior Reversible Encephalopathy Syndrome (PRES) involving unilateral lesions are very rare. We searched the PubMed database using keywords such as PRES, unilateral, and asymmetric and found a small number of cases to include in our review. We summarized the characteristics of these reported cases of unilateral PRES, including our case.

Background The aim of the present study was to investigate the efficacy and safety of antiplatelet (aspirin plus cilostazol) dual therapy for patients with noncardioembolic stroke within 48 hours of symptom onset. Methods and Results The ADS (Acute Aspirin Plus Cilostazol Dual Therapy for Non-Cardiogenic Stroke Patients Within 48 Hours of Symptom Onset ) study is an investigator-initiated, prospective, multicenter (34 hospitals in Japan), randomized, open-label, and aspirin-controlled trial. Acute stroke patients with noncardioembolic stroke within 48 hours of onset were studied. The subjects were randomly allocated to combination therapy with aspirin 81 to 200 mg plus cilostazol 200 mg (dual group) and single therapy with aspirin 81 to 200 mg (aspirin group) for 14 days. After the 14 days, all patients took the cilostazol 200 mg for 3 months. A primary efficacy outcome was defined as any one of the following occurring (neurological deterioration, symptomatic stroke recurrence, or transient ischemic attack) within 14 days. A primary safety outcome included intracerebral hemorrhage and subarachnoid hemorrhage. Between May 2011 and June 2017, 1201 patients (796 [66%] men; median age, 69 [61-77] years) randomized 1:1 to either the dual group or the aspirin group were analyzed. Initial National Institutes of Health Stroke Scale score was 2 (1-4) in both groups (P=0.830). A primary efficacy outcome was observed in 11% in the dual group and 11% in the aspirin group (P=0.853). A primary safety outcome occurred in 2 (0.3%) in the dual group and in 1 (0.2%) in the aspirin group (P=0.624). Conclusions Dual antiplatelet therapy using cilostazol and aspirin was safe but did not reduce the rate of short-term neurological worsening. Clinical Trial Registration URL: umin.ac.jp/ctr/index/htm. Unique identifier: UMIN000004950.

Isolated vertigo is an important symptom of posterior circulation stroke. It has been reported that 11.3% of patients with isolated vertigo have a stroke and that most lesions are located in the cerebellum, particularly in the posterior inferior cerebellar artery. We report the case of a 63-year-old man with multiple atherosclerotic risk factors and atrial fibrillation who showed repeated episodes of isolated vertigo. His repeated vertigo was short-lasting and was often triggered by body position, mimicking benign paroxysmal positional vertigo. Cranial computed tomography on the third hospital day showed left cerebellar infarction within the territory of the posterior inferior cerebellar artery. The vertigo was ameliorated on the fifth hospital day and warfarin was prescribed for secondary prevention. Clinicians should pay special attention to cases in which a patient presents isolated vertigo, even if it shows transient recurrence or is triggered by a positional change, especially in patients with multiple cerebrovascular risk factors.

BACKGROUND: Cerebral microbleeds (CMBs) are often observed in Parkinson's disease (PD); however, their association with cognitive decline has been unclear. We performed a retrospective analysis of 124 cases of clinically diagnosed PD to determine the association between the presence of CMBs and cognitive decline. RESULTS: Of the 124 participants, 21 (16.9%) was diagnosed as PDD in this cohort. CMBs were observed significantly more frequently in the PDD than in the PD (47.6% vs 7.8%, P < .001). The presence of both deep/infratentorial (40% vs 14.9%, P < .05) and strictly lobar (75% vs 12.9%, P < .001) CMBs were associated with PDD. The values of cognitive scales such as Mini-Mental State Examination and the Hasegawa Dementia Scale-revised, were also significantly lower in the presence of each type of CMB. A multivariable logistic regression analysis showed the presence of strictly lobar CMBs as well as a male gender, orthostatic hypotension, periventricular hyperintensity on magnetic resonance imaging were significantly associated with PDD in this cohort. CONCLUSIONS: This study showed the presence of CMBs, especially strictly lobar type, was strongly associated with PDD. We suspect that the burden of small vessel disease and cerebral amyloid angiopathy may be related to the development of cognitive decline in PD, and a prospective study enrolling more cases is warranted.

Background: The management of atrial fibrillation (AF) has evolved with the development of direct oral anticoagulants (DOACs), but data on their clinical effectiveness and safety outside clinical trial settings are limited. Method: The RAFFINE registry is an observational, multicenter, prospective registry of Japanese patients with AF, designed to follow clinical events over 3 years. Patient enrollment was conducted from 2013 to 2015 at university hospitals, general hospitals, and private clinics to ensure inclusion of a broad spectrum of representative AF patients. The primary outcome events in this study will be ischemic stroke, systemic embolism, and major bleeding. Result: We enrolled 3901 ambulatory patients with AF from 4 university hospitals and 50 general hospitals/clinics in Japan. The mean patient age was 72.6 years and 68.5% were male. The type of AF was paroxysmal in 37.8%, persistent in 9.3%, and permanent in 51.7%. Major coexisting diseases were hypertension (72.7%), diabetes mellitus (30.3%), congestive heart failure (23.8%), history of ischemic stroke or transient ischemic attack (15.1%), and coronary artery disease (13.7%). Of the entire cohort, 44.6% were treated with warfarin and 43.0% were treated with DOACs. The prescription of DOACs exceeded that of warfarin in the general hospitals and clinics. Risk scores such as CHADS2 score, CHA2DS2-VASc score, and HAS-BLED score were higher in patients at university hospitals than in patients at general hospitals or clinics. Conclusion: The RAFFINE registry at baseline described the current status of anticoagulation therapy in Japan and long-term follow-up data will identify how outcomes vary between stratified groups in patients with AF in the DOAC era (UMIN Clinical Trials Registry UMIN000009617).

Loss of integrity of the blood-brain barrier (BBB) in ischemic stroke victims initiates a devastating cascade of events causing brain damage. Maintaining the BBB is important to preserve brain function in ischemic stroke. Unfortunately, recombinant tissue plasminogen activator (tPA), the only effective fibrinolytic treatment at the acute stage of ischemic stroke, also injures the BBB and increases the risk of brain edema and secondary hemorrhagic transformation. Thus, it is important to identify compounds that maintain BBB integrity in the face of ischemic injury in patients with stroke. We previously demonstrated that intravenously injected phosphorylated recombinant heat shock protein 27 (prHSP27) protects the brains of mice with transient middle cerebral artery occlusion (tMCAO), an animal stroke-model. Here, we determined whether prHSP27, in addition to attenuating brain injury, also decreases BBB damage in hyperglycemic tMCAO mice that had received tPA. After induction of hyperglycemia and tMCAO, we examined 4 treatment groups: 1) bovine serum albumin (BSA), 2) prHSP27, 3) tPA, 4) tPA plus prHSP27. We examined the effects of prHSP27 by comparing the BSA and prHSP27 groups and the tPA and tPA plus prHSP27 groups. Twenty-four hours after injection, prHSP27 reduced infarct volume, brain swelling, neurological deficits, the loss of microvessel proteins and endothelial cell walls, and mortality. It also reduced the rates of hemorrhagic transformation, extravasation of endogenous IgG, and MMP-9 activity, signs of BBB damage. Therefore, prHSP27 injection attenuated brain damage and preserved the BBB in tPA-injected, hyperglycemic tMCAO experimental stroke-model mice, in which the BBB is even more severely damaged than in simple tMCAO mice. The attenuation of brain damage and BBB disruption in the presence of tPA suggests the effectiveness of prHSP27 and tPA as a combination therapy. prHSP27 may be a novel therapeutic agent for ischemic stroke patients whose BBBs are injured following tPA injections.

Blood pressure abnormalities are frequently observed in patients with Parkinson's disease (PD), and are associated with cerebrovascular diseases such as white matter hyperintensities and carotid atherosclerosis. We assessed the relationship between blood pressure abnormalities and cerebral microbleeds (CMBs), a marker of cerebral small vessel disease, in 128 patients with PD. We examined supine and orthostatic blood pressures and used 24-hour ambulatory blood pressure monitoring to assess the presence or absence of orthostatic hypotension (OH), supine hypertension (SH), nocturnal hypertension (NH), and loss of nocturnal blood pressure dips (non-dipping). CMBs were found in 13 (10.2%) patients, and the median number of CMBs was 1 (range: 1 to 10). Six of these patients had deep or infratentorial CMBs, six had strictly lobar CMBs, and one had mixed CMBs. Linear regression analysis indicated that presence of both OH and SH was independently associated with greater numbers of CMBs in deep or infratentorial regions, independent of age, sex, cardiovascular risk factors, and white matter hyperintensities. NH and non-dipping were not associated with CMBs in deep or infratentorial regions, and there was no association between blood pressure and CMBs in lobar regions. Our results suggest that the presence of both OH and SH may be related to deep or infratentorial CMBs in patients with PD.