Stroke genetics informs drug discovery and risk prediction across ancestries.

Previous genome-wide association studies (GWASs) of stroke - the second leading cause of death worldwide - were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis3, and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach4, we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry5. Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries.

Deletion of Nox4 enhances remyelination following cuprizone-induced demyelination by increasing phagocytic capacity of microglia and macrophages in mice.

NOX4 is a major reactive oxygen species-producing enzyme that modulates cell stress responses. We here examined the effect of Nox4 deletion on demyelination-remyelination, the most common pathological change in the brain. We used a model of cuprizone (CPZ)-associated demyelination-remyelination in wild-type and Nox4-deficient (Nox4-/- ) mice. While the CPZ-induced demyelination in the corpus callosum after 4 weeks of CPZ intoxication was slightly less pronounced in Nox4-/- mice than that in wild-type mice, remyelination following CPZ withdrawal was significantly enhanced in Nox4-/- mice with an increased accumulation of IBA1-positive microglia/macrophages in the demyelinating corpus callosum. Consistently, locomotor function, as assessed by the beam walking test, was significantly better during the remyelination phase in Nox4-/- mice. Nox4 deletion did not affect autonomous growth of primary-culture oligodendrocyte precursor cells. Although Nox4 expression was higher in cultured macrophages than in microglia, Nox4-/- microglia and macrophages both showed enhanced phagocytic capacity of myelin debris and produced increased amounts of trophic factors upon phagocytosis. The expression of trophic factors was higher, in parallel with the accumulation of IBA1-positive cells, in the corpus callosum in Nox4-/- mice than that in wild-type mice. Nox4 deletion suppressed phagocytosis-induced increase in mitochondrial membrane potential, enhancing phagocytic capacity of macrophages. Treatment with culture medium of Nox4-/- macrophages engulfing myelin debris, but not that of Nox4-/- astrocytes, enhanced cell growth and expression of myelin-associated proteins in cultured oligodendrocyte precursor cells. Collectively, Nox4 deletion promoted remyelination after CPZ-induced demyelination by enhancing microglia/macrophage-mediated clearance of myelin debris and the production of trophic factors leading to oligodendrogenesis.

Decreased Estimated Glomerular Filtration Rate and Proteinuria and Long-Term Outcomes After Ischemic Stroke: A Longitudinal Observational Cohort Study.

BACKGROUND: It remains unclear how chronic kidney disease and its underlying pathological conditions, kidney dysfunction, and kidney damage, are associated with cardiovascular outcomes. This study aimed to determine whether kidney dysfunction (ie, decreased estimated glomerular filtration rate), kidney damage (ie, proteinuria), or both are associated with the long-term outcomes after ischemic stroke. METHODS: A total of 12 576 patients (mean age, 73.0±12.6 years; 41.3% women) with ischemic stroke who were registered in a hospital-based multicenter registry, Fukuoka Stroke Registry, between June 2007 and September 2019, were prospectively followed up after stroke onset. Kidney function was assessed by estimated glomerular filtration rate and categorized into G1: ≥60 mL/(min·1.73 m2), G2: 45-59 mL/(min·1.73 m2), and G3: <45 mL/(min·1.73 m2). Kidney damage was evaluated by proteinuria using a urine dipstick test and classified into P1: -, P2: ±/1+, and P3: ≥2+. Hazard ratios and 95% CI for events of interest were estimated by a Cox proportional hazards model. Long-term outcomes included recurrence of stroke and all-cause death. RESULTS: During the median follow-up of 4.3 years (interquartile range, 2.1-7.3 years), 2481 patients had recurrent stroke (48.0/1000 patient-years) and 4032 patients died (67.3/1000 patient-years). Chronic kidney disease was independently associated with increased risks of stroke recurrence and all-cause death even after adjustment for multiple confounding factors, including traditional cardiovascular risk factors. Both estimated glomerular filtration rate and proteinuria were independently associated with increased risks of stroke recurrence (multivariable-adjusted hazard ratio [95% CI], G3: 1.22 [1.09-1.37] versus G1, P3: 1.25 [1.07-1.46] versus P1) and death (G3: 1.45 [1.33-1.57] versus G1, P3: 1.62 [1.45-1.81] versus P1). In subgroup analyses, effect modifications were found in the association of proteinuria with death by age and stroke subtype. CONCLUSIONS: Kidney dysfunction and kidney damage were independently, but differently, associated with increased risks of recurrent stroke and all-cause death.

Association between Early Cognitive Impairment and Short-Term Functional Outcome in Acute Ischemic Stroke.

BACKGROUND: Little is known about the association between poststroke cognitive impairment (PSCI) and functional outcome in the acute care phase of ischemic stroke and the influence of the clinical condition of acute stroke on this association. We examined this issue, taking into account stroke-related factors, in a hospital-based prospective study of patients with acute ischemic stroke. The same analysis was also performed after subsequent rehabilitation to investigate whether the association observed in the acute care phase persisted after that. For comparison, the same analysis was performed for pre-stroke dementia (PreSD). METHODS: We included in the study a total of 923 patients with acute ischemic stroke who were admitted to a hospital from 2012 to 2020 in Japan. Cognitive function was assessed using the Mini-Mental State Examination and Raven's Colored Progressive Matrices test at an average of 6.3 days after stroke onset. The subjects were divided into three groups with normal cognition, PSCI, and PreSD. Study outcome was a poor functional outcome, defined as a modified Rankin Scale score of ≥3 at the end of acute care (median 21 days after admission). Among total subjects, 460 were also assessed for poor functional outcome after rehabilitation (median 77 days after admission). A logistic regression model was applied in this study. RESULTS: Patients with PSCI and PreSD had higher median National Institute of Health Stroke Scale scores than those with normal cognition (median [IQR]: 3 [2-6], 4 [2-12], and 2 [1-4], respectively). The age- and sex-adjusted cumulative incidence of poor functional outcome was significantly higher in patients with PSCI and PreSD than in those with normal cognition in the acute care and rehabilitation phases. In the acute care phase, these associations remained significant after adjustment for stroke-related factors and other confounders (multivariable-adjusted odds ratio [95% CI] for PSCI vs. normal cognition: 3.28 [2.07-5.20]; for PreSD: 2.39 [1.40-4.08]). Similar results were observed in the rehabilitation phase (for PSCI: 2.48 [1.31-4.70]; for PreSD: 3.92 [1.94-7.92]). CONCLUSIONS: Our findings suggest that PSCI, as well as PreSD, is possibly associated with the development of poor functional outcome in the acute care phase of ischemic stroke, and this association continues thereafter.

Sex Differences in Long-Term Functional Decline after Ischemic Stroke: A Longitudinal Observational Study from the Fukuoka Stroke Registry.

INTRODUCTION: Data on sex differences in poststroke functional status for a period longer than 1 year based on large cohorts are sparse. This study aimed to determine whether there are sex differences in long-term functional decline after ischemic stroke. METHODS: We tracked functional status for 5 years among 3-month survivors of acute ischemic stroke and compared outcomes between women and men using a large-scale hospital-based stroke registry in Fukuoka, Japan. Functional status was assessed using the modified Rankin Scale (mRS). Functional dependency was defined as an mRS score of 3, 4, or 5. Logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals of outcomes after adjusting for possible confounders. RESULTS: A total of 8,446 patients (71.9 ± 12.5 years, 3,377 (40.0%) female patients) were enrolled in this study. Female sex was associated with a higher risk of functional dependency at 5 years poststroke even when adjusting for age, 3-month mRS score, and other confounding factors (multivariable-adjusted OR vs. men, 1.56 [95% confidence interval, 1.26-1.93]). This significant association of female sex with higher dependency at 5 years was also found among patients who were independent at 3 months poststroke. Subgroup analysis showed that increased risk of functional dependency in female patients was more marked in patients aged ≥75 years than in those aged <75 years (p for heterogeneity = 0.02). Conversely, female sex was associated with a lower risk of death. No sex difference was observed in stroke recurrence during 5 years poststroke. DISCUSSION/CONCLUSION: This longitudinal observational study suggests that female sex was independently associated with an increased risk of functional decline in the chronic phase of stroke, especially in older patients. There was no sex difference in 5-year stroke recurrence, and thus, other factors might be involved in more significant deterioration of functional status in female survivors of ischemic stroke. Further studies are needed to elucidate underlying causes of sex differences in long-term functional decline after stroke.

A redox-dependent pathway for regulating class II HDACs and cardiac hypertrophy.

Thioredoxin 1 (Trx1) facilitates the reduction of signaling molecules and transcription factors by cysteine thiol-disulfide exchange, thereby regulating cell growth and death. Here we studied the molecular mechanism by which Trx1 attenuates cardiac hypertrophy. Trx1 upregulates DnaJb5, a heat shock protein 40, and forms a multiple-protein complex with DnaJb5 and class II histone deacetylases (HDACs), master negative regulators of cardiac hypertrophy. Both Cys-274/Cys-276 in DnaJb5 and Cys-667/Cys-669 in HDAC4 are oxidized and form intramolecular disulfide bonds in response to reactive oxygen species (ROS)-generating hypertrophic stimuli, such as phenylephrine, whereas they are reduced by Trx1. Whereas reduction of Cys-274/Cys-276 in DnaJb5 is essential for interaction between DnaJb5 and HDAC4, reduction of Cys-667/Cys-669 in HDAC4 inhibits its nuclear export, independently of its phosphorylation status. Our study reveals a novel regulatory mechanism of cardiac hypertrophy through which the nucleocytoplasmic shuttling of class II HDACs is modulated by their redox modification in a Trx1-sensitive manner.

An elderly case with late carotid stent thrombosis: possible role of antiphospholipid antibodies.

The case study speculates that the antiphospholipid antibodies acquired during the follow-up period of carotid artery stenting may cause late stent thrombosis that is resistant to direct oral anticoagulants. A 73-year-old man was hospitalized with complaints of weakness in the right lower extremity. The patient had undergone carotid artery stenting for symptomatic stenosis of the left internal carotid artery 6 years prior and had received antiplatelet therapy with clopidogrel 75 mg/day. As the patient had developed atrial fibrillation without stent stenosis at the age of 70 years, anticoagulation therapy with rivaroxaban15 mg/day was initiated while discontinuing clopidogrel. On admission, diffusion weighted imaging (DWI) revealed acute brain infarcts in the territory of the left middle cerebral artery. Contrast-enhanced computed tomography and cerebral angiography exposed severe stenosis in the left carotid artery accompanied by a filling defect caused by a floating thrombus. Laboratory examination revealed the presence of three types of antiphospholipid antibodies, with marked prolongation of activated partial thromboplastin time (APTT). Replacement of rivaroxaban with warfarin eliminated the thrombus without recurrent stroke. In conclusion, late stent thrombosis may be associated with antiphospholipid antibodies acquired during the follow-up period of carotid artery stenting.

Day-by-Day Blood Pressure Variability in the Subacute Stage of Ischemic Stroke and Long-Term Recurrence.

BACKGROUND AND PURPOSE: This study aimed to determine whether variability of day-by-day blood pressure (BP) during the subacute stage of acute ischemic stroke is predictive of long-term stroke recurrence. METHODS: We analyzed 7665 patients (mean±SD age: 72.9±13.1 years; women: 42.4%) hospitalized for first-ever ischemic stroke in 7 stroke centers in Fukuoka, Japan, from June 2007 to November 2018. BP was measured daily during the subacute stage (4-10 days after onset). Its mean and coefficient of variation (CV) values were calculated and divided into 4 groups according to the quartiles of these BP parameters. Patients were prospectively followed up for recurrent stroke or all-cause death. The cumulative event rate was calculated with the Kaplan-Meier method. We estimated the hazard ratios and 95% confidence intervals of the events of interest after adjusting for potential confounders and mean BP values using Cox proportional hazards models. The Fine-Gray model was also used to account for the competing risk of death. RESULTS: With a mean (±SD) follow-up duration of 3.9±3.2 years, the rates of recurrent stroke and all-cause death were 3.9 and 9.9 per 100 patient-years, respectively. The cumulative event rates of recurrent stroke and all-cause death increased with increasing CVs of systolic BP and diastolic BP. The systolic BP CV was significantly associated with an increased risk of recurrent stroke after adjusting for multiple confounders and mean BP (hazard ratio [95% CI] for fourth quartile versus first quartile, 1.26 [1.05-1.50]); the risk of recurrent stroke also increased with an increasing systolic BP CV for nonfatal strokes (1.26 [1.05-1.51]) and when death was regarded as a competing risk (1.21 [1.02-1.45]). Similar associations were observed for the diastolic BP CV. CONCLUSIONS: Day-by-day variability of BP during the subacute stage of acute ischemic stroke was associated with an increased long-term risk of recurrent stroke.

Progressive Small-Vessel Strokes Following Antiretroviral Therapy in a Patient with Acquired Immunodeficiency Syndrome.

We report a case of a 59-year-old man with human immunodeficiency virus (HIV)/ acquired immunodeficiency syndrome (AIDS) who developed multiple small-vessel strokes during the immune reconstitution phase. The patient had been diagnosed with HIV/AIDS with a low CD4 count and high viral load and started combinational antiretroviral therapy (cART) with raltegravir, emtricitabine, and tenofovir alafenamide fumarate seven months before the admission. He was admitted to our hospital with complaints of mild dysarthria and left-sided hemiparesis, but lacking consciousness/cognitive disturbances. Diffusion-weighted images (DWI) revealed multiple areas of hyperintensity in the anterior circulation system of the brain. Because we identified decreased activity of protein S through extensive examinations, we treated him initially with intravenous infusion of heparin sodium and aspirin; however, DWI detected multiple progressive small-vessel strokes after that. We considered that the immune reconstitution accounted for the small-vessel vasculopathy/vasculitis, leading to ischemic stroke. Therefore, we initiated oral administration of prednisolone, which successfully prevented stroke recurrence. This report describes a case of multiple small-vessel strokes following cART for AIDS during the immune reconstitution phase, effectively treated with steroids, which may often go undiagnosed due to their relatively mild symptoms.

ß-Cell Function and Clinical Outcome in Nondiabetic Patients With Acute Ischemic Stroke.

Background and Purpose: Little is known about how ß-cell dysfunction affects clinical outcome after ischemic stroke. We examined whether ß-cell function is associated with clinical outcome after acute ischemic stroke and if so, whether insulin resistance influences this association in a prospective study of patients with acute stroke. Methods: A total of 3590 nondiabetic patients with acute ischemic stroke (mean age, 71 years) were followed up for 3 months. ß-Cell function was assessed using the homeostasis model assessment for ß-cell function (HOMA-ß). Study outcomes were poor functional outcome (modified Rankin Scale score, 3­6) and stroke recurrence at 3 months after stroke onset and neurological deterioration (≥2-point increase in the National Institutes of Health Stroke Scale score) at discharge. Logistic regression analysis was used to evaluate the association between quintile levels of serum HOMA-ß and clinical outcomes. Results: The age- and sex-adjusted odds ratios for poor functional outcome and neurological deterioration increased significantly with decreasing HOMA-ß levels (P for trend, <0.001 and 0.001, respectively). These associations became more prominent after adjustment for HOMA-insulin resistance and were substantially unchanged even after further adjustment for other confounders, namely, body mass index, dyslipidemia, hypertension, estimated glomerular filtration rate, stroke subtype, National Institutes of Health Stroke Scale score on admission, and reperfusion therapy (odds ratio [95% CI] for the first versus fifth quintile of HOMA-ß, 3.30 [2.15­5.08] for poor functional outcome and 10.69 [4.99­22.90] for neurological deterioration). Such associations were not observed for stroke recurrence. In stratified analysis for the combination of HOMA-ß and HOMA-insulin resistance levels, lower HOMA-ß and higher HOMA-insulin resistance levels were independently associated with increased risks of poor functional outcome and neurological deterioration. Conclusions: Our findings suggest that ß-cell dysfunction is significantly associated with poor short-term clinical outcome independently of insulin resistance in nondiabetic patients with acute ischemic stroke.

Pre-Stroke Cholinesterase Inhibitor Treatment Is Beneficially Associated with Functional Outcome in Patients with Acute Ischemic Stroke and Pre-Stroke Dementia: The Fukuoka Stroke Registry.

INTRODUCTION: Pre-stroke dementia is significantly associated with poor stroke outcome. Cholinesterase inhibitors (ChEIs) might reduce the risk of stroke in patients with dementia. However, the association between pre-stroke ChEI treatment and stroke outcome remains unresolved. Therefore, we aimed to determine this association in patients with acute ischemic stroke and pre-stroke dementia. METHODS: We enrolled 805 patients with pre-stroke dementia among 13,167 with ischemic stroke within 7 days of onset who were registered in the Fukuoka Stroke Registry between June 2007 and May 2019 and were independent in basic activities of daily living (ADLs) before admission. Primary and secondary study outcomes were poor functional outcome (modified Rankin Scale [mRS] score: 3-6) at 3 months after stroke onset and neurological deterioration (≥2-point increase in the NIH Stroke Scale [NIHSS] during hospitalization), respectively. Logistic regression analysis was used to evaluate associations between pre-stroke ChEI treatment and study outcomes. To improve covariate imbalance, we further conducted a propensity score (PS)-matched cohort study. RESULTS: Among the participants, 212 (26.3%) had pre-stroke ChEI treatment. Treatment was negatively associated with poor functional outcome (odds ratio: 0.68 [95% confidence interval: 0.46-0.99]) and neurological deterioration (0.52 [0.31-0.88]) after adjusting for potential confounding factors. In the PS-matched cohort study, the same trends were observed between pre-stroke ChEI treatment and poor functional outcome (0.61 [0.40-0.92]) and between the treatment and neurological deterioration (0.47 [0.25-0.86]). CONCLUSIONS: Our findings suggest that pre-stroke ChEI treatment is associated with reduced risks for poor functional outcome and neurological deterioration after acute ischemic stroke in patients with pre-stroke dementia who are independent in basic ADLs before the onset of stroke.

Reciprocal Interaction Between Pericytes and Macrophage in Poststroke Tissue Repair and Functional Recovery.

BACKGROUND AND PURPOSE: Poststroke tissue repair, comprised of macrophage-mediated clearance of myelin debris and pericyte-mediated fibrotic response within the infarct area, is an important process for functional recovery. Herein, we investigated the reciprocal interaction between pericytes and macrophages during poststroke repair and functional recovery. METHODS: We performed a permanent middle cerebral artery occlusion in both wild-type and pericyte-deficient PDGFRß (platelet-derived growth factor receptor ß) heterozygous knockout (Pdgfrb+/-) mice and compared histological changes and neurological functions between the 2 groups. We also examined the effects of conditioned medium harvested from cultured pericytes, or bone marrow-derived macrophages, on the functions of other cell types. RESULTS: Localization of PDGFRß-positive pericytes and F4/80-positive macrophages was temporally and spatially very similar following permanent middle cerebral artery occlusion. Intrainfarct accumulation of macrophages was significantly attenuated in Pdgfrb+/- mice. Intrainfarct pericytes expressed CCL2 (C-C motif ligand 2) and CSF1 (colony stimulating factor 1), both of which were significantly lower in Pdgfrb+/- mice. Cultured pericytes expressed Ccl2 and Csf1, both of which were significantly increased by PDGF-BB and suppressed by a PDGFRß inhibitor. Pericyte conditioned medium significantly enhanced migration and proliferation of bone marrow-derived macrophages. Poststroke clearance of myelin debris was significantly attenuated in Pdgfrb+/- mice. Pericyte conditioned medium promoted phagocytic activity in bone marrow-derived macrophages, also enhancing both STAT3 (signal transducer and activator of transcription 3) phosphorylation and expression of scavenger receptors, Msr1 and Lrp1. Macrophages processing myelin debris produced trophic factors, enhancing PDGFRß signaling in pericytes leading to the production of ECM (extracellular matrix) proteins and oligodendrogenesis. Functional recovery was significantly attenuated in Pdgfrb+/- mice, parallel with the extent of tissue repair. CONCLUSIONS: A reciprocal interaction between pericytes and macrophages is important for poststroke tissue repair and functional recovery.

Smoking Status and Functional Outcomes After Acute Ischemic Stroke.

Background and Purpose- Smoking is an established risk factor for stroke; however, it is uncertain whether prestroke smoking status affects clinical outcomes of acute ischemic stroke. This study aimed to elucidate the association between smoking status and functional outcomes after acute ischemic stroke. Methods- Using a multicenter hospital-based stroke registry in Japan, we investigated 10 825 patients with acute ischemic stroke hospitalized between July 2007 and December 2017 who had been independent before stroke onset. Smoking status was categorized into those who had never smoked (nonsmokers), former smokers, and current smokers. Clinical outcomes included poor functional outcome (modified Rankin Scale score ≥2) and functional dependence (modified Rankin Scale score 2-5) at 3 months. We adjusted for potential confounding factors using a logistic regression analysis. Results- The mean age of patients was 70.2±12.2 years, and 37.0% were women. There were 4396 (42.7%) nonsmokers, 3328 (32.4%) former smokers, and 2561 (24.9%) current smokers. The odds ratio (95% CI) for poor functional outcome after adjusting for confounders increased in current smokers (1.29 [1.11-1.49] versus nonsmokers) but not in former smokers (1.05 [0.92-1.21] versus nonsmokers). However, among the former smokers, the odds ratio of poor functional outcome was higher in those who quit smoking within 2 years of stroke onset (1.75 [1.15-2.66] versus nonsmokers). The risk of poor functional outcome tended to increase as the number of daily cigarettes increased in current smokers (P for trend=0.002). All these associations were maintained for functional dependence. Conclusions- Current and recent smoking is associated with an increased risk of unfavorable functional outcomes at 3 months after acute ischemic stroke. Registration- URL: http://www.fukuoka-stroke.net/english/index.html. Unique identifier: 000000800.

Anticoagulation and Risk of Stroke Recurrence in Patients with Embolic Stroke of Undetermined Source Having No Potential Source of Embolism.

BACKGROUND: This study aimed to determine whether use of oral anticoagulants (OACs) was associated with a reduced risk of recurrent stroke compared with use of antiplatelets (APs) in patients with embolic stroke of undetermined source (ESUS) having no potential source of embolism. METHODS: Of 8,790 patients with acute ischemic stroke registered at 7 centers in the Fukuoka Stroke Registry from June 2007 to May 2017, we included 681 patients (mean age 69.7 [SD 14.1] years, 48.3% men) who experienced ESUS without a potential source of embolism and received OAC alone or AP alone. We estimated hazard ratios (HRs) and 95% confidential intervals (CIs) of recurrent ischemic stroke or any stroke after discharge using a Cox proportional hazards model and Fine and Gray model. RESULTS: During a mean follow-up of 3.4 (SD 1.7) years, event rates of recurrent ischemic stroke were 4.4 per 100 person-years in 489 patients treated with AP and 2.0 per 100 person-years in 192 patients treated with OAC. OAC use was associated with a reduced risk of recurrent ischemic stroke, even after adjusting for potential confounding factors (multivariable-adjusted HR [95% CI], 0.42 [0.23-0.80]) and when additionally considering death as a competing risk (0.45 [0.24-0.85]). The reduced risk of recurrent ischemic stroke was still observed in patients treated with OAC (0.32 [0.15-0.67]) in reference to propensity score-matched patients treated with AP. These associations were maintained for all types of stroke, including ischemic and hemorrhagic stroke. CONCLUSIONS: This nonrandomized observational study suggests that anticoagulation therapy might be associated with a reduced risk of recurrent stroke compared with antiplatelet therapy in patients with ESUS in whom no potential source of embolism was identified. Further study should be performed in consideration of a potential source of embolism even in patients with ESUS.

An Embolic Stroke in a Patient With PROC p.Lys193del.

We report a 58-year-old woman who suddenly developed brain infarction with weakness of the left lower extremity and left perioral dysesthesia during postoperative tamoxifen therapy for breast cancer and prednisolone therapy for rheumatoid arthritis. Diffusion-weighted images detected multiple areas of hyperintensity in the posterior circulation system of the brain. Despite extensive examinations, we could not identify any embolic sources except hypoplasia of the right vertebral artery. We found decreased activity of protein C against its antigen level (activity: 59% versus antigen: 122%) with enhanced activity of coagulation factor VIII (178%) and von Willebrand factor (285%). DNA sequencing identified trinucleotide deletion of the PROC gene leading to 1 amino acid deletion at Lys-193 (p.Lys193del). We speculate that the PROC gene polymorphism may have participated in tamoxifen- and prednisolone- associated hypercoagulable state, leading to development of an embolic stroke in this patient.

Arterial Spin Labeling Magnetic Resonance Imaging for Differentiating Acute Ischemic Stroke from Epileptic Disorders.

BACKGROUND: Differential diagnosis between acute ischemic stroke (AIS) and epilepsy-related stroke mimics is sometimes difficult in the emergency department. We investigated whether a combination of diffusion-weighted imaging (DWI) and arterial spin labeling imaging (ASL) is useful in distinguishing AIS from epileptic disorders. METHODS: The study included suspected AIS patients who underwent emergency MRI including both DWI and ASL, and who exhibited DWI high-intensity lesions corresponding to neurological symptoms. We investigated the relationship between the ASL results from within and/or around DWI lesions and the final clinical diagnosis. RESULTS: Eighty-five cases were included (mean age, 71 ± 13 years; 47 men). The time from onset to the MRI examination was 493 ± 536 minutes. ASL showed hyperintensity in 13 patients, isointensity in 43, and hypointensity in 29. All ASL hyperintensities were observed in the cortex, with 4 patients (31%) presenting with AIS and 9 (69%) with an epileptic disorder. All of the AIS patients with ASL hyperintensity were diagnosed with cardioembolic stroke (4/4, 100%), with magnetic resonance angiography demonstrating recanalization of the occluded artery in all cases (4/4, 100%). In the 9 patients with an epileptic disorder, the area of ASL hyperintensity typically extended beyond the vascular territory (7/9, 78%) and involved the ipsilateral thalamus (7/9, 78%). All patients with ASL isointensity and hypointensity were diagnosed with AIS; none had epileptic disorders. CONCLUSIONS: Although cortical ASL hyperintensity can indicate cardioembolic stroke with recanalization, hyperintensity beyond the vascular territory may alternatively suggest an epileptic disorder in suspected AIS patients with DWI lesions.

Quality Management Program of Stroke Rehabilitation Using Adherence to Guidelines: A Nationwide Initiative in Japan.

BACKGROUND AND AIM: In recent years, interest in the quality of medical care has rapidly increased worldwide. However, quality indicators that contribute to establishing standard treatment in stroke medicine, especially rehabilitation, are not well-developed in Japan. Japan has established Kaifukuki (convalescent) rehabilitation wards, and the development of quality indicators for stroke rehabilitation in the convalescent phase is an urgent issue. METHODS: We first reviewed the literature regarding quality indicators for stroke rehabilitation. Next, we extracted candidate indicators from identified reports and guidelines and surveyed educational hospitals certified by the Japanese Association of Rehabilitation Medicine. On the basis of the survey results, we reevaluated the suitability of the proposed indicators in discussions with an expert panel. RESULTS: The questionnaire survey highlighted several important items that revealed there is room for improvement in adherence. For stroke rehabilitation in the convalescent phase, we adopted 15 indicators that were feasible as indicators to be used for comparisons between facilities, based on scoring by and opinions of the expert panel. These indicators measured structure (2 indicators), process (5 indicators), and outcome (8 indicators). CONCLUSION: This is the first study to establish quality indicators to standardize stroke rehabilitation in Japan. We developed this set of 15 indicators using an evidence-based approach. However, many tasks remain for continuous quality improvement.

[A case of autoimmune hemolytic anemia diagnosed by occurrence of cardioembolic stroke].

A 79-year-old woman came to us because of sudden onset of dysarthria. She had taken apixaban due to her non-valvular atrial fibrillation. A neurological examination revealed mild facial palsy of her right side, and magnetic resonance imaging showed acute brain infarction at the left frontal lobe. There were no stenotic lesions on intracranial or extracranial magnetic resonance angiography, and she was diagnosed with cardioembolic stroke. Intravenous infusion of heparin and edaravone was initiated, and her neurological symptoms improved. However, she gradually developed jaundice and anemia. Gastro-intestinal bleeding was not observed, and her blood test met the diagnostic criteria for hemolytic anemia. Because both the direct Coombs test and cold agglutinin were positive, she was diagnosed with mixed-type autoimmune hemolytic anemia. Although her serum hemoglobin level decreased to 7.0 g/dl on the 12th hospital day, her anemia gradually improved after steroidal therapy with transfusion. It was revealed that she had shown mild anemia (hemoglobin: 9.2-10.9 g/dl) and hyperbilirubinemia (total bilirubin: 1.8-2.6 mg/dl) for 6 months. Therefore, her latent autoimmune hemolytic anemia became activated with the occurrence of cardioembolic stroke. Autoimmune hemolytic anemia might have promoted cardiac thrombus formation despite the administration of an anticoagulant in this case. It should be noted that autoimmune hemolytic anemia can develop as thrombotic disease. In the present case, autoimmune hemolytic anemia was diagnosed based on the development of cardioembolic stroke.

A case of hyperparathyroidism-associated parkinsonism successfully treated with cinacalcet hydrochloride, a calcimimetic.

BACKGROUND: Some metabolic disorders, including abnormal calcium metabolism, can develop and worsen parkinsonism. However, whether hyperparathyroidism can cause parkinsonism remains controversial. CASE PRESENTATION: An 83-year-old woman with a history of right thalamic hemorrhage and drug-induced parkinsonism, was admitted due to worsening of parkinsonian symptoms including mask-like face, bradykinesia, freezing of gait, and rigidity. She had been diagnosed with autoimmune hepatitis and was being treated with prednisolone. Examinations revealed hypercalcemia (14.3 mg/dL) with an increased level of intact parathyroid hormone (iPTH) (361 pg/mL). Her symptoms were resistant to some additional anti-parkinsonian drugs; however, cinacalcet hydrochloride, a calcimimetic for the treatment of secondary hyperparathyroidism, normalized levels of serum calcium and iPTH, and remarkably improved her symptoms. CONCLUSIONS: In the present case, we speculate that hypercalcemia probably due to secondary hyperparathyroidism that had developed during steroid therapy deteriorated the parkinsonism.