Predictive Performance of Machine Learning-Based Models for Poststroke Clinical Outcomes in Comparison With Conventional Prognostic Scores: Multicenter, Hospital-Based Observational Study.

BACKGROUND: Although machine learning is a promising tool for making prognoses, the performance of machine learning in predicting outcomes after stroke remains to be examined. OBJECTIVE: This study aims to examine how much data-driven models with machine learning improve predictive performance for poststroke outcomes compared with conventional stroke prognostic scores and to elucidate how explanatory variables in machine learning-based models differ from the items of the stroke prognostic scores. METHODS: We used data from 10,513 patients who were registered in a multicenter prospective stroke registry in Japan between 2007 and 2017. The outcomes were poor functional outcome (modified Rankin Scale score >2) and death at 3 months after stroke. Machine learning-based models were developed using all variables with regularization methods, random forests, or boosted trees. We selected 3 stroke prognostic scores, namely, ASTRAL (Acute Stroke Registry and Analysis of Lausanne), PLAN (preadmission comorbidities, level of consciousness, age, neurologic deficit), and iScore (Ischemic Stroke Predictive Risk Score) for comparison. Item-based regression models were developed using the items of these 3 scores. The model performance was assessed in terms of discrimination and calibration. To compare the predictive performance of the data-driven model with that of the item-based model, we performed internal validation after random splits of identical populations into 80% of patients as a training set and 20% of patients as a test set; the models were developed in the training set and were validated in the test set. We evaluated the contribution of each variable to the models and compared the predictors used in the machine learning-based models with the items of the stroke prognostic scores. RESULTS: The mean age of the study patients was 73.0 (SD 12.5) years, and 59.1% (6209/10,513) of them were men. The area under the receiver operating characteristic curves and the area under the precision-recall curves for predicting poststroke outcomes were higher for machine learning-based models than for item-based models in identical populations after random splits. Machine learning-based models also performed better than item-based models in terms of the Brier score. Machine learning-based models used different explanatory variables, such as laboratory data, from the items of the conventional stroke prognostic scores. Including these data in the machine learning-based models as explanatory variables improved performance in predicting outcomes after stroke, especially poststroke death. CONCLUSIONS: Machine learning-based models performed better in predicting poststroke outcomes than regression models using the items of conventional stroke prognostic scores, although they required additional variables, such as laboratory data, to attain improved performance. Further studies are warranted to validate the usefulness of machine learning in clinical settings.

Effect of smoking status on clinical outcomes after reperfusion therapy for acute ischemic stroke.

Smoking has detrimental effects on the cardiovascular system; however, some studies have reported better clinical outcomes after thrombolysis for ischemic stroke in smokers than in nonsmokers, a phenomenon known as the smoking paradox. Therefore, this study aimed to examine the smoking paradox in patients with ischemic stroke receiving reperfusion therapy. Data were collected from a multicenter hospital-based acute stroke registry in Fukuoka, Japan. The 1148 study patients were categorized into current and noncurrent smokers. The association between smoking and clinical outcomes, including neurological improvement (≥ 4-point decrease in the National Institutes of Health Stroke Scale during hospitalization or 0 points at discharge) and good functional outcomes (modified Rankin Scale score of 0-2) at 3 months, was evaluated using logistic regression analysis and propensity score-matched analysis. Among the participants, 231 (20.1%) were current smokers. The odds ratios (ORs) of favorable outcomes after adjusting for potential confounders were not significantly increased in current smokers (OR 0.85, 95% confidence interval [CI] 0.60-1.22 for neurological improvement; OR 0.95, 95% CI 0.65-1.38 for good functional outcome). No significant association was found in the propensity score-matched cohorts. Smoking cessation is strongly recommended since current smoking was not associated with better outcomes after reperfusion therapy.

Body temperature in the acute phase and clinical outcomes after acute ischemic stroke.

BACKGROUND: This study aimed to examine whether post-stroke early body temperature is associated with neurological damage in the acute phase and functional outcomes at three months. METHODS: We included 7,177 patients with acute ischemic stroke within 24 h of onset. Axillary temperature was measured daily in the morning for seven days. Mean body temperature was grouped into five quintiles (Q1: 35.1‒36.5°C, Q2: 36.5‒36.7°C, Q3: 36.7‒36.8°C, Q4: 36.8‒37.1°C, and Q5: 37.1‒39.1°C). Clinical outcomes included neurological improvement during hospitalization and poor functional outcome (modified Rankin scale score, 3-6) at three months. A logistic regression analysis was performed to evaluate the association between body temperature and clinical outcomes. RESULTS: The patient's mean (SD) age was 70.6 (12.3) years, and 35.7% of patients were women. Mean body temperature was significantly associated with less neurological improvement from Q2 (odds ratios [95% confidence interval], 0.77 [0.65-0.99] vs. Q1) to Q5 (0.33 [0.28-0.40], P for trend <0.001) even after adjusting for potential confounders, including baseline neurological severity, C-reactive protein levels, and post-stroke acute infections. The multivariable-adjusted risk of poor functional outcome linearly increased from Q2 (1.36 [1.03-1.79]) to Q5 (6.44 [5.19-8.96], P for trend <0.001). These associations were maintained even in the analyses excluding patients with acute infectious diseases. Multivariable-adjusted risk of poor functional outcome was higher in patients with early body temperature elevation on days 1-3 and with longer duration with body temperature >37.0°C. CONCLUSIONS: Post-stroke early high body temperature is independently associated with unfavorable outcomes following acute ischemic stroke.

Association between abdominal adiposity and clinical outcomes in patients with acute ischemic stroke.

BACKGROUND: It is unclear whether abdominal adiposity has an additional effect on post-stroke outcomes. This study aimed to determine whether waist circumference (WC) is independently associated with clinical outcomes after acute ischemic stroke. METHODS: We enrolled patients with acute ischemic stroke from a multicenter hospital-based stroke registry in Fukuoka, Japan. We measured WC on admission and categorized patients into four groups (Q1-Q4) according to the quartiles in females and males. The clinical outcomes were poor functional outcome (modified Rankin scale score 2-6) and death from any cause. Logistic regression analysis was performed to estimate the odds ratio and 95% confidence interval of the outcomes of interest after adjusting for potential confounding factors, including body mass index (BMI). RESULTS: A total of 11,989 patients (70.3±12.2 years, females: 36.1%) were included in the analysis. The risk of poor functional outcome significantly decreased for Q2-Q4 (vs. Q1) at discharge and Q2-Q3 (vs. Q1) at 3 months, even after adjusting for potential confounders, including BMI. In contrast, adjustment of BMI eliminated the significant association between WC and all-cause death at discharge and 3 months. The association between high WC and favorable functional outcome was not affected by fasting insulin levels or homeostatic model assessment for insulin resistance and was only found in patients without diabetes (P = 0.02 for heterogeneity). CONCLUSIONS: These findings suggest that abdominal adiposity has an additional impact on post-stroke functional outcome, independent of body weight and insulin action.

[A case of recurrent stroke with carotid-web despite dabigatran treatment successfully treated by carotid endarterectomy].

We present a case of a 41-year-old female presenting with recurrence of ischemic stroke on subtherapeutic doses of dabigatran. She had a history of embolic stroke of undetermined sources at the age of 40, and underwent implantable cardiac monitor implantation and had started dabigatran. One year after the first ischemic stroke, she presented with sudden dysarthria and left hemiparesis and was admitted to our hospital. An MRI of the head revealed acute cerebral infarction in the right corona radiata, and an MR angiography revealed right M2 occlusion. Cervical 3D-CTA revealed a protruding structure on the posterior wall of the carotid artery bulb, which was diagnosed as carotid web. She underwent carotid endarterectomy, and the specimen was pathologically confirmed to be vascular malformation due to fibromuscular dysplasia.

Association between decreases in serum uric acid levels and unfavorable outcomes after ischemic stroke: A multicenter hospital-based observational study.

BACKGROUND: The association between clinical outcomes in ischemic stroke patients and decreases in serum uric acid levels, which often occur during the acute phase, remains unknown. Herein, we aimed to investigate the association using a large-scale, multicenter stroke registry. METHODS: We analyzed 4,621 acute ischemic stroke patients enrolled in the Fukuoka Stroke Registry between June 2007 and September 2019 whose uric acid levels were measured at least twice during hospitalization (including on admission). The study outcomes were poor functional outcome (modified Rankin Scale score ≥3) and functional dependence (modified Rankin Scale score 3-5) at 3 months after stroke onset. Changes in uric acid levels after admission were evaluated using a decrease rate that was classified into 4 sex-specific grades ranging from G1 (no change/increase after admission) to G4 (most decreased). Multivariable logistic regression analyses were used to assess the associations between decreases in uric acid levels and the outcomes. RESULTS: The frequencies of the poor functional outcome and functional dependence were lowest in G1 and highest in G4. The odds ratios (95% confidence intervals) of G4 were significantly higher for poor functional outcome (2.66 [2.05-3.44]) and functional dependence (2.61 [2.00-3.42]) when compared with G1 after adjusting for confounding factors. We observed no heterogeneity in results for subgroups categorized according to age, sex, stroke subtype, neurological severity, chronic kidney disease, or uric acid level on admission. CONCLUSIONS: Decreases in serum uric acid levels were independently associated with unfavorable outcomes after acute ischemic stroke.

Non-linear association between body weight and functional outcome after acute ischemic stroke.

This study aimed to determine whether body weight is associated with functional outcome after acute ischemic stroke. We measured the body mass index (BMI) and assessed clinical outcomes in patients with acute ischemic stroke. The BMI was categorized into underweight (< 18.5 kg/m2), normal weight (18.5-22.9 kg/m2), overweight (23.0-24.9 kg/m2), and obesity (≥ 25.0 kg/m2). The association between BMI and a poor functional outcome (modified Rankin Scale [mRS] score: 3-6) was evaluated. We included 11,749 patients with acute ischemic stroke (70.3 ± 12.2 years, 36.1% women). The risk of a 3-month poor functional outcome was higher for underweight, lower for overweight, and did not change for obesity in reference to a normal weight even after adjusting for covariates by logistic regression analysis. Restricted cubic splines and SHapley Additive exPlanation values in eXtreme Gradient Boosting model also showed non-linear relationships. Associations between BMI and a poor functional outcome were maintained even after excluding death (mRS score: 3-5) or including mild disability (mRS score: 2-6) as the outcome. The associations were strong in older patients, non-diabetic patients, and patients with mild stroke. Body weight has a non-linear relationship with the risk of a poor functional outcome after acute ischemic stroke.

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.

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.

Modification of the effects of age on clinical outcomes through management of lifestyle-related factors in patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: This study examined the association between age and clinical outcomes after ischemic stroke, and whether the effect of age on post-stroke outcomes can be modified by various factors. METHODS: We included 12,171 patients with acute ischemic stroke, who were functionally independent before stroke onset, in a multicenter hospital-based study conducted in Fukuoka, Japan. Patients were categorized into six groups according to age: ≤ 45, 46-55, 56-65, 66-75, 76-85, and > 85 years. Logistic regression analysis was performed to estimate an odds ratio for poor functional outcome (modified Rankin scale score of 3-6 at 3 months) for each age group. Interaction effects of age and various factors were analyzed using a multivariable model. RESULTS: The mean age of the patients was 70.3 ± 12.2 years, and 63.9% were men. Neurological deficits at onset were more severe in the older age groups. The odds ratio of poor functional outcome linearly increased (P for trend <0.001), even after adjusting for potential confounders. Sex, body mass index, hypertension, and diabetes mellitus significantly modified the effect of age on the outcome (P < 0.05). The unfavorable effect of older age was greater in female patients and those with low body weight, whereas the protective effect of younger age was smaller in patients with hypertension or diabetes mellitus. CONCLUSIONS: Functional outcome worsened with age in patients with acute ischemic stroke, especially in females and those with low body weight, hypertension, or hyperglycemia.

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.

PDGFRß-positive cell-mediated post-stroke remodeling of fibronectin and laminin α2 for tissue repair and functional recovery.

Post-stroke intra-infarct repair promotes peri-infarct neural reorganization leading to functional recovery. Herein, we examined the remodeling of extracellular matrix proteins (ECM) that constitute the intact basal membrane after permanent middle cerebral artery occlusion (pMCAO) in mice. Among ECM, collagen type IV remained localized on small vessel walls surrounding CD31-positive endothelial cells within infarct areas. Fibronectin was gradually deposited from peri-infarct areas to the ischemic core, in parallel with the accumulation of PDGFRß-positive cells. Cultured PDGFRß-positive pericytes produced fibronectin, which was enhanced by the treatment with PDGF-BB. Intra-infarct deposition of fibronectin was significantly attenuated in pericyte-deficient Pdgfrb+/-mice. Phagocytic activity of macrophages against myelin debris was significantly enhanced on fibronectin-coated dishes. In contrast, laminin α2, produced by GFAP- and aquaporin 4-positive astrocytes, accumulated strongly in the boundary of peri-infarct areas. Pericyte-conditioned medium increased the expression of laminin α2 in cultured astrocytes, partly through TGFß1. Laminin α2 increased the differentiation of oligodendrocyte precursor cells into oligodendrocytes and the expression of myelin-associated proteins. Peri-infarct deposition of laminin α2 was significantly reduced in Pdgfrb+/-mice, with attenuated oligodendrogenesis in peri-infarct areas. Collectively, intra-infarct PDGFRß-positive cells may orchestrate post-stroke remodeling of key ECM that create optimal environments promoting clearance of myelin debris and peri-infarct oligodendrogenesis.

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.

Low-dose sodium-glucose cotransporter 2 inhibitor ameliorates ischemic brain injury in mice through pericyte protection without glucose-lowering effects.

Antidiabetic sodium-glucose cotransporter 2 (SGLT2) inhibitors have attracted attention for their cardiorenal-protective properties beyond their glucose-lowering effect. However, their benefits in ischemic stroke remain controversial. Here we show the effects of luseogliflozin, a selective SGLT2 inhibitor, in acute ischemic stroke, using a permanent middle cerebral artery occlusion (pMCAO) model in non-diabetic mice. Pretreatment with low-dose luseogliflozin, which does not affect blood glucose levels, significantly attenuated infarct volume, blood-brain barrier disruption, and motor dysfunction after pMCAO. SGLT2 was expressed predominantly in brain pericytes and was upregulated in peri- and intra-infarct areas. Notably, luseogliflozin pretreatment reduced pericyte loss in ischemic areas. In cultured pericytes, luseogliflozin activated AMP-activated protein kinase α and increased mitochondrial transcription factor A expression and number of mitochondria, conferring resistance to oxygen-glucose deprivation. Collectively, pre-stroke inhibition of SGLT2 induces ischemic tolerance in brain pericytes independent of the glucose-lowering effect, contributing to the attenuation of ischemic brain injury.

Causes of ischemic stroke in young adults versus non-young adults: A multicenter hospital-based observational study.

BACKGROUND: Very few comparative studies have focused on the differences in the causes of ischemic stroke between young adults and non-young adults. This study was performed to determine what causes of ischemic stroke are more important in young adults than in non-young adults using a large-scale multicenter hospital-based stroke registry in Fukuoka, Japan. METHODS AND RESULTS: We investigated data on 15,860 consecutive patients aged ≥18 years with acute ischemic stroke (mean age: 73.5 ± 12.4 years, 58.2% men) who were hospitalized between 2007 and 2019. In total, 779 patients were categorized as young adults (≤50 years of age). Although vascular risk factors, including hypertension, diabetes mellitus, and dyslipidemia, were less frequent in young adults than in non-young adults, the prevalence of diabetes mellitus and dyslipidemia in young adults aged >40 years were comparable to those of non-young adults. Lifestyle-related risk factors such as smoking, drinking, and obesity were more frequent in young adults than in non-young adults. As young adults became older, the proportions of cardioembolism and stroke of other determined etiologies decreased, but those of large-artery atherosclerosis and small-vessel occlusion increased. Some embolic sources (high-risk sources: arterial myxoma, dilated cardiomyopathy, and intracardiac thrombus; medium-risk sources: atrial septal defect, nonbacterial thrombotic endocarditis, patent foramen ovale, and left ventricular hypokinesis) and uncommon causes (vascular diseases: reversible cerebral vasoconstriction syndrome, moyamoya disease, other vascular causes, arterial dissection, and cerebral venous thrombosis; hematologic diseases: antiphospholipid syndrome and protein S deficiency) were more prevalent in young adults than in non-young adults, and these trends decreased with age. CONCLUSIONS: Certain embolic sources and uncommon causes may be etiologically important causes of ischemic stroke in young adults. However, the contribution of conventional vascular risk factors and lifestyle-related risk factors is not negligible with advancing age, even in young adults.

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.

Long-Term Trends in The 5-Year Risk of Recurrent Stroke over A Half Century in A Japanese Community: The Hisayama Study.

AIM: Secular trends in the risk of recurrent stroke have been reported in several epidemiological studies worldwide, but this issue has not been investigated in general Japanese populations. We examined the trends in the 5-year risk of recurrent stroke over a half century using community-based prospective data in Japan. METHODS: We established 4 cohort studies in 1961, 1974, 1988, and 2002. To examine the risk of recurrent stroke, participants who developed stroke during a 10-year follow-up period in each cohort were followed-up for 5 years from the date of first onset. A total of 154 (first sub-cohort: 1961-1971), 144 (second sub-cohort: 1974-1984), 172 (third sub-cohort: 1988-1998), and 146 (fourth sub-cohort: 2002-2012) participants from each cohort were enrolled in the present study. The 5-year cumulative risk of recurrent stroke was compared among the sub-cohorts using the Kaplan-Meier method and the age- and sex-adjusted Cox proportional hazards model. RESULTS: The risks of recurrent stroke after any stroke and ischemic stroke decreased significantly from the first to the third sub-cohort, but they did not clearly change from the third to the fourth sub-cohort. The risk of recurrent stroke after hemorrhagic stroke decreased mainly from the first to the second sub-cohort and there was no apparent decrease from the second to the fourth sub-cohort. These trends were substantially unchanged after adjusting for age and sex. CONCLUSIONS: In the Japanese community, the risk of recurrent stroke decreased mainly from the 1960s to 1990s, but there was no apparent decrease in recent years.

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.

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.