IMPORTANCE Data are limited regarding the association between CYP2C19 genetic variants and clinical outcomes of patients with minor stroke or transient ischemic attack treated with clopidogrel. OBJECTIVE To estimate the association between CYP2C19 genetic variants and clinical outcomes of clopidogrel-treated patients with minor stroke or transient ischemic attack. DESIGN, SETTING, AND PARTICIPANTS Three CYP2C19 major alleles (*2, *3, *17) were genotyped among 2933 Chinese patients from 73 sites who were enrolled in the Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events (CHANCE) randomized trial conducted from January 2, 2010, to March 20, 2012. INTERVENTIONS Patients with acute minor ischemic stroke or transient ischemic attack in the trial were randomized to treatment with clopidogrel combined with aspirin or to aspirin alone. MAIN OUTCOMES AND MEASURESThe primary efficacy outcome was new stroke. The secondary efficacy outcome was a composite of new composite vascular events (ischemic stroke, hemorrhagic stroke, myocardial infarction, or vascular death). Bleeding was the safety outcome. RESULTS Among 2933 patients, 1948 (66.4%) were men, with a mean age of 62.4 years. Overall, 1207 patients (41.2%) were noncarriers and 1726 patients (58.8%) were carriers of loss-of-function alleles (*2, *3). After day 90 follow-up, clopidogrel-aspirin reduced the rate of new stroke in the noncarriers but not in the carriers of the loss-of-function alleles (P = .02 for interaction; events among noncarriers, 41 [6.7%] with clopidogrel-aspirin vs 74 [12.4%] with aspirin; hazard ratio [HR], 0.51 [95% CI, 0.35-0.75]; events among carriers, 80 [9.4%] with clopidogrel-aspirin vs 94 [10.8%] with aspirin; HR, 0.93 [95% CI, 0.69 to 1.26]). Similar results were observed for the secondary composite efficacy outcome (noncarriers: 41 [6.7%] with clopidogrel-aspirin vs 75 [12.5%] with aspirin; HR, 0.50 [95% CI, 0.34-0.74]; carriers: 80 [9.4%] with clopidogrel-aspirin vs 95 [10.9%] with aspirin; HR, 0.92 [95% CI, 0.68-1.24]; P = .02 for interaction). The effect of treatment assignment on bleeding did not vary significantly between the carriers and the noncarriers of the loss-of-function alleles (2.3% for carriers and 2.5% for noncarriers in the clopidogrel-aspirin group vs 1.4% for carriers and 1.7% for noncarriers in the aspirin only group; P = .78 for interaction). CONCLUSIONS AND RELEVANCE Among patients with minor ischemic stroke or transient ischemic attack, the use of clopidogrel plus aspirin compared with aspirin alone reduced the risk of a new stroke only in the subgroup of patients who were not carriers of the CYP2C19 loss-of-function alleles. These findings support a role of CYP2C19 genotype in the efficacy of this treatment.
Background and purposeStroke is the leading cause of mortality and disability in China. Precise aetiological classification, imaging and biological markers may predict the prognosis of stroke. The Third China National Stroke Registry (CNSR-III), a nationwide registry of ischaemic stroke or transient ischaemic attack (TIA) in China based on aetiology, imaging and biology markers, will be considered to clarify the pathogenesis and prognostic factors of ischaemic stroke.MethodsBetween August 2015 and March 2018, the CNSR-III recruited consecutive patients with ischaemic stroke or TIA from 201 hospitals that cover 22 provinces and four municipalities in China. Clinical data were collected prospectively using an electronic data capture system by face-to-face interviews. Patients were followed for clinical outcomes at 3 months, 6 months and 1–5 year annually. Brain imaging, including brain MRI and CT, were completed at baseline. Blood samples were collected and biomarkers were tested at baseline.ResultsA total of 15 166 stroke patients were enrolled, among which 31.7% patients were women with the average age of 62.2±11.3 years. Ischaemic stroke was predominant (93.3%, n=14 146) and 1020 (6.7%) TIAs were enrolled.ConclusionsCNSR-III is a large scale nationwide registry in China. Data from this prospective registry may provide opportunity to evaluate imaging and biomarker prognostic determinants of stroke.
Cerebrovascular white matter lesions represent an age-related neurodegenerative condition that appears as a hyperintense signal on magnetic resonance images. These lesions are frequently observed in aging, hypertension and cerebrovascular disease, and are responsible for cognitive decline and gait disorders in the elderly population. In humans, cerebrovascular white matter lesions are accompanied by apoptosis of oligodendroglia, and have been thought to be caused by chronic cerebral ischemia. In the present study, we tested whether chronic cerebral hypoperfusion induces white matter lesions and apoptosis of oligodendroglia in the rat. Doppler flow meter analysis revealed an immediate reduction of cerebral blood flow ranging from 30% to 40% of that before operation; this remained at 52-64% between 7 and 30 days after operation. Transferrin-immunoreactive oligodendroglia decreased in number and the myelin became degenerated in the medial corpus callosum at 7 days and thereafter. Using the TUNEL method, the number of cells showing DNA fragmentation increased three- to eightfold between 3 and 30 days post-surgery compared to sham-operated animals. Double labeling with TUNEL and immunohistochemistry for markers of either astroglia or oligodendroglia showed that DNA fragmentation occurred in both of these glia. Messenger RNA for caspase-3 increased approximately twofold versus the sham-operated rats between 1 and 30 days post-surgery. Immunohistochemistry revealed up-regulation of caspase-3 in the oligodendroglia of the white matter, and also in the astroglia and neurons of the gray matter. Molecules involved in apoptotic signaling such as TNF-alpha and Bax were also up-regulated in glial cells. These results indicate that chronic cerebral hypoperfusion induces white matter degeneration in association with DNA fragmentation in oligodendroglia.
ObjectiveTo test the hypothesis that ticagrelor plus aspirin is safe and superior to clopidogrel plus aspirin for reducing high platelet reactivity at 90 days and stroke recurrence in patients with minor stroke or transient ischaemic attack, particularly in carriers of the CYP2C19 loss-of-function allele and patients with large artery atherosclerosis.DesignOpen label, blinded endpoint, randomised controlled phase II trial.SettingProspective studies conducted at 26 centres in China, August 2015 to March 2017.Participants675 patients with acute minor stroke or transient ischaemic attack.InterventionTicagrelor (180 mg loading dose, 90 mg twice daily thereafter) or clopidogrel (300 mg loading dose, 75 mg daily thereafter) on a background of aspirin (100 mg daily for the first 21 days) within 24 hours of symptom onset.Main outcome measuresPrimary outcome was the proportion of patients with high platelet reactivity at 90 days. High platelet reactivity was defined as P2Y12 reaction units of more than 208. Secondary outcomes included high platelet reactivity at 90 days (7 days either way) in patients carrying genetic variants that would affect clopidogrel metabolism, and any stroke (ischaemic or haemorrhagic) recurrence at 90 days (7 days either way), six months, and one year.ResultsAt 90 days, high platelet reactivity occurred in 35 (12.5%) of 280 patients in the ticagrelor/aspirin group and 86 (29.7%) of 290 patients in the clopidogrel/aspirin group (risk ratio 0.40; 95% confidence interval 0.28 to 0.56; P<0.001), and in 10.8% versus 35.4% (0.31; 0.18 to 0.49; P<0.001) of patients carrying CYP2C19 loss-of-function alleles. Stroke occurred in 21 (6.3%) of 336 patients in the ticagrelor/aspirin group and 30 (8.8%) of 339 patients in the clopidogrel/aspirin group (hazard ratio 0.70; 95% confidence interval 0.40 to 1.22; P=0.20). Patients with large artery atherosclerosis in the ticagrelor/aspirin group had a lower stroke recurrence at 90 days than those in the clopidogrel/aspirin group (6.0% v 13.1%; hazard ratio 0.45, 95% confidence interval 0.20 to 0.98; P=0.04). No difference was seen in the rates of major or minor haemorrhagic events between the ticagrelor/aspirin and clopidogrel/aspirin groups (4.8% v 3.5%; P=0.42).ConclusionPatients with minor stroke or transient ischaemic attack who are treated with ticagrelor plus aspirin have a lower proportion of high platelet reactivity than those who are treated with clopidogrel plus aspirin, particularly for those who are carriers of the CYP2C19 loss-of-function allele. The results of this study should be evaluated further in large scale, phase III trials and in different populations.Trial registrationClinicaltrials.gov NCT02506140.
The authors used surface-based anatomic mapping to detect features of hippocampal anatomy that correlated with surgical outcomes in patients undergoing surgery for mesial temporal lobe epilepsy with hippocampal sclerosis. Compared with a seizure-free group, hippocampal profiles for the non-seizure-free group had greater diffuse ipsilateral atrophy and more region-specific contralateral atrophy in the anterior, lateral hippocampus. These atrophic regions may indicate areas of increased epileptogenicity, contributing to poorer surgical outcomes.
Background and purposeCardiovascular diseases and dementia are two major diseases in the elderly. Atherosclerosis is associated with future vascular events and cognitive impairment. The PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study is a population-based prospective cohort study with comprehensive evaluation of multiterritorial artery stenosis and plaque using advanced vascular imaging techniques and prospective collection of vascular events and cognitive assessments.MethodsBetween May 2017 and September 2019, the PRECISE study enrolled 3067 community-dwelling adults with ages between 50 and 75 years cluster sampled from six villages and four communities of Lishui city in China. Data are collected in face-to-face interviews at baseline, 2-year and 4-year follow-up visits. Brain MRI including high-resolution sequences for intracranial and carotidal arteries and CT angiography for thoracoabdominal arteries were performed at baseline and will be rescanned after 4 years. Cardiovascular/cerebrovascular events and cognitive assessment will be prospectively collected after the enrollment. Blood and urine samples were collected and biomarkers were tested at baseline.ResultsA total of 3067 subjects were enrolled, among which 53.5% were female with an average age of 61.2±6.7 years. Among them, 2.8%, 8.1%, 43.1% and 21.6% had a history of stroke, coronary heart diseases, hypertension and diabetes mellitus, respectively.ConclusionsThe PRECISE study is a population-based prospective cohort study with comprehensive evaluation of atherosclerotic stenosis and plaque using advanced vascular imaging techniques. Data from this cohort provide us an opportunity to precisely evaluate polyvascular atherosclerosis and its association with future vascular events and cognitive impairment.Trial registration numberClinicalTrials.gov Registry (NCT03178448).
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