oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
The Efficacy and Adverse Reaction of Bleeding of Clopidogrel plus Aspirin as Compared to Aspirin Alone after Stroke or TIA: A Systematic Review  [PDF]
Yan Huang, Man Li, Jian-Yong Li, Min Li, Yuan-Peng Xia, Ling Mao, Bo Hu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0065754
Abstract: Background and Purpose Given the high risk of stroke after TIA (transient ischemia attack) or stroke and the adverse reaction of bleeding of antiplatelets, we undertook a meta-analysis, reviewed randomized controlled trials (RCTs) comparing aspirin plus clopidogrel with aspirin alone to determine the efficacy and adverse reaction of bleeding of the two protocols in the prevention of stroke. Methods We analyzed the incidences of stroke, bleeding and severe bleeding by using fixed-effect model or random-effect model on the basis of the result of heterogeneity test. Results Five qualified RCTs satisfied the inclusion criteria. We found that treatment with aspirin plus clopidogrel was associated with lower incidence of stroke (Risk Ratio (RR), 0.66, 95% confidence interval (CI), 0.47 to 0.93), higher incidence of bleeding (RR, 1.75, 95% CI, 1.48 to 2.05) as compared with aspirin-alone treatment. In terms of severe bleeding, no statistical difference existed between them (RR, 2.21, 95% CI, 0.25 to 19.52). Conclusion The combined use of aspirin and clopidogrel is more effective than aspirin alone for patients with previous TIA or stroke for the prevention of stroke, with risk of bleeding being higher. No statistical difference was found in severe bleeding between the two treatment protocols.
Clinical importance of aspirin and clopidogrel resistance  [cached]
Gergely Feher,Andrea Feher,Gabriella Pusch,Katalin Koltai
World Journal of Cardiology , 2010,
Abstract: Aspirin and clopidogrel are important components of medical therapy for patients with acute coronary syndromes, for those who received coronary artery stents and in the secondary prevention of ischaemic stroke. Despite their use, a significant number of patients experience recurrent adverse ischaemic events. Interindividual variability of platelet aggregation in response to these antiplatelet agents may be an explanation for some of these recurrent events, and small trials have linked “aspirin and/or clopidogrel resistance”, as measured by platelet function tests, to adverse events. We systematically reviewed all available evidence on the prevalence of aspirin/clopidogrel resistance, their possible risk factors and their association with clinical outcomes. We also identified articles showing possible treatments. After analyzing the data on different laboratory methods, we found that aspirin/clopidogrel resistance seems to be associated with poor clinical outcomes and there is currently no standardized or widely accepted definition of clopidogrel resistance. Therefore, we conclude that specific treatment recommendations are not established for patients who exhibit high platelet reactivity during aspirin/clopidogrel therapy or who have poor platelet inhibition by clopidogrel.
Comparative effect of clopidogrel plus aspirin and aspirin monotherapy on hematological parameters using propensity score matching
Hayasaka M, Takahashi Y, Nishida Y, Yoshida Y, Hidaka S, Asai S
Vascular Health and Risk Management , 2013, DOI: http://dx.doi.org/10.2147/VHRM.S39351
Abstract: mparative effect of clopidogrel plus aspirin and aspirin monotherapy on hematological parameters using propensity score matching Original Research (603) Total Article Views Authors: Hayasaka M, Takahashi Y, Nishida Y, Yoshida Y, Hidaka S, Asai S Published Date February 2013 Volume 2013:9 Pages 65 - 70 DOI: http://dx.doi.org/10.2147/VHRM.S39351 Received: 18 October 2012 Accepted: 10 December 2012 Published: 18 February 2013 Masatoshi Hayasaka,1 Yasuo Takahashi,2 Yayoi Nishida,2 Yoshikazu Yoshida,1 Shinji Hidaka,3 Satoshi Asai4 1Department of Pharmacy, Nihon University Itabashi Hospital, Tokyo, 2Division of Genomic Epidemiology and Clinical Trials, Clinical Trials Research Center, Nihon University School of Medicine, Tokyo, 3Laboratory of Pharmaceutical Regulatory Science, Department of Pharmacy, School of Pharmacy, Nihon University, Chiba, 4Division of Pharmacology, Department of Biomedical Sciences, Nihon University School of Medicine, Tokyo, Japan Background: Clopidogrel and aspirin are antiplatelet agents that are recommended to reduce the risk of recurrent stroke and other cardiovascular events. Dual antiplatelet therapy with clopidogrel and aspirin has been shown to increase the risk of hemorrhage, but the effects of the drugs on laboratory parameters have not been well studied in real-world clinical settings. Therefore, we evaluated and compared the effects of combination therapy with clopidogrel plus aspirin and aspirin monotherapy on laboratory parameters. Methods: We used data from the Nihon University School of Medicine Clinical Data Warehouse obtained between November 2004 and May 2011 to identify cohorts of new users (n = 130) of clopidogrel (75 mg/day) plus aspirin (100 mg/day) and a propensity score matched sample of new users (n = 130) of aspirin alone (100 mg/day). We used a multivariate regression model to compare serum levels of creatinine, aspartate aminotransferase, and alanine aminotransferase, as well as hematological parameters including hemoglobin level, hematocrit, and white blood cell, red blood cell, and platelet counts up to 2 months after the start of administration of the study drugs. Results: There were no significant differences for any characteristics and baseline laboratory parameters between users of clopidogrel plus aspirin and users of aspirin alone. Reductions in white blood cell and red blood cell counts, hemoglobin levels, and hematocrit in users of clopidogrel plus aspirin were significantly greater than those in users of aspirin alone. Conclusion: Our findings suggest that adverse hematological effects may be greater with combination clopidogrel plus aspirin therapy than with aspirin monotherapy.
Comparative effect of clopidogrel plus aspirin and aspirin monotherapy on hematological parameters using propensity score matching  [cached]
Hayasaka M,Takahashi Y,Nishida Y,Yoshida Y
Vascular Health and Risk Management , 2013,
Abstract: Masatoshi Hayasaka,1 Yasuo Takahashi,2 Yayoi Nishida,2 Yoshikazu Yoshida,1 Shinji Hidaka,3 Satoshi Asai41Department of Pharmacy, Nihon University Itabashi Hospital, Tokyo, 2Division of Genomic Epidemiology and Clinical Trials, Clinical Trials Research Center, Nihon University School of Medicine, Tokyo, 3Laboratory of Pharmaceutical Regulatory Science, Department of Pharmacy, School of Pharmacy, Nihon University, Chiba, 4Division of Pharmacology, Department of Biomedical Sciences, Nihon University School of Medicine, Tokyo, JapanBackground: Clopidogrel and aspirin are antiplatelet agents that are recommended to reduce the risk of recurrent stroke and other cardiovascular events. Dual antiplatelet therapy with clopidogrel and aspirin has been shown to increase the risk of hemorrhage, but the effects of the drugs on laboratory parameters have not been well studied in real-world clinical settings. Therefore, we evaluated and compared the effects of combination therapy with clopidogrel plus aspirin and aspirin monotherapy on laboratory parameters.Methods: We used data from the Nihon University School of Medicine Clinical Data Warehouse obtained between November 2004 and May 2011 to identify cohorts of new users (n = 130) of clopidogrel (75 mg/day) plus aspirin (100 mg/day) and a propensity score matched sample of new users (n = 130) of aspirin alone (100 mg/day). We used a multivariate regression model to compare serum levels of creatinine, aspartate aminotransferase, and alanine aminotransferase, as well as hematological parameters including hemoglobin level, hematocrit, and white blood cell, red blood cell, and platelet counts up to 2 months after the start of administration of the study drugs.Results: There were no significant differences for any characteristics and baseline laboratory parameters between users of clopidogrel plus aspirin and users of aspirin alone. Reductions in white blood cell and red blood cell counts, hemoglobin levels, and hematocrit in users of clopidogrel plus aspirin were significantly greater than those in users of aspirin alone.Conclusion: Our findings suggest that adverse hematological effects may be greater with combination clopidogrel plus aspirin therapy than with aspirin monotherapy.Keywords: clopidogrel, aspirin, laboratory parameter, antiplatelet therapy, propensity score matching
Aspirin- and Clopidogrel-associated Bleeding Complications: Data Mining of the Public Version of the FDA Adverse Event Reporting System, AERS  [cached]
Takao Tamura, Toshiyuki Sakaeda, Kaori Kadoyama, Yasushi Okuno
International Journal of Medical Sciences , 2012,
Abstract: Objective: Adverse event reports (AERs) submitted to the US Food and Drug Administration (FDA) were reviewed to assess the bleeding complications induced by the administration of antiplatelets and to attempt to determine the rank-order of the association. Methods: After a deletion of duplicated submissions and the revision of arbitrary drug names, AERs involving warfarin, aspirin, cilostazol, clopidogrel, ethyl icosapentate, limaprost alfadex, sarpogrelate, and ticlopidine were analyzed. Authorized pharmacovigilance tools were used for the quantitative detection of signals, i.e., drug-associated adverse events, including the proportional reporting ratio, the reporting odds ratio, the information component given by a Bayesian confidence propagation neural network, and the empirical Bayes geometric mean. Results: Based on 22,017,956 co-occurrences, i.e., drug-adverse event pairs, found in 1,644,220 AERs from 2004 to 2009, 736 adverse events were listed as warfarin-associated adverse events, and 147 of the 736 were bleeding complications, including haemorrhage and haematoma. Both aspirin and clopidogrel were associated with haemorrhage, but the association was more noteworthy for clopidogrel. As for bleeding complications related to the gastrointestinal system, e.g., melaena and haematochezia, the statistical metrics suggested a stronger association for aspirin than clopidogrel. The total number of co-occurrences was not large enough to compare the association with bleeding complications for the other 5 antiplatelets. Conclusions: The data strongly suggest the necessity of well-organized clinical studies with respect to antiplatelet-associated bleeding complications.
Markers of hypercoagulability in CAD patients. Effects of single aspirin and clopidogrel treatment
Bratseth Vibeke,Pettersen Alf-?ge,Opstad Trine B,Arnesen Harald
Thrombosis Journal , 2012, DOI: 10.1186/1477-9560-10-12
Abstract: Background Cardiovascular disease with disturbances in the haemostatic system, might lead to thrombotic complications with clinical manifestations like acute myocardial infarction (AMI) and stroke. Activation of the coagulation cascade with subsequent increased thrombin generation, characterizes a prothrombotic phenotype. In the present study we investigated whether prothrombotic markers were associated with risk factors and clinical subgroups in a cohort of patients with angiographically verified coronary artery disease (CAD). The patients were randomized to long-term treatment with the antiplatelet drugs aspirin or clopidogrel, and we further investigated the effect on hypercoagulability of such treatment for 1 year, of which limited data exists. Methods Venous blood samples were collected in fasting condition between 08:00 and 10:30 am, at baseline when all patients were on aspirin therapy (n = 1001) and in 276 patients after 1 year follow-up on aspirin or clopidogrel. In vivo thrombin generation was assessed by prothrombin fragment 1 + 2 (F1+2) and D-dimer, and the endogenous thrombin potentiale (ETP) in the calibrated automated thrombogram (CAT) assay, representing ex vivo thrombin generation. In addition soluble tissue factor (sTF) and free- and total tissue factor pathway inhibitor (TFPI) were measured. Results We found age to be significantly associated with F1+2 and D-dimer (β = 0.229 and β =0.417 respectively, p <0.001, both). Otherwise, only weak associations were found. F1+2 and D-dimer were higher in women compared to men (p <0.001 and p = 0.033, respectively). Smokers had elevated levels of ETP compared to non-smokers (p = 0.014). Additionally, patients on renin-angiotensin system (RAS) inhibition showed significantly higher levels of F1+2, compared to non-users (p = 0.013). Both aspirin and clopidogrel reduced levels of ETP after 12 months intervention (p = 0.003 and p <0.001, respectively) and the levels of F1+2 were significantly more reduced on aspirin compared to clopidogrel (p = 0.023). Conclusions In the present population of stable CAD, we could demonstrate a more hypercoagulable profile among women, smokers and patients on RAS medication, assessed by the prothrombotic markers F1+2, D-dimer and ETP. Long-term antiplatelet treatment with aspirin alone seems to attenuate thrombin generation to a greater extent than with clopidogrel alone. The study is registered at http://www.clinicaltrials.gov: NCT00222261.
A Randomised Controlled Trial of Triple Antiplatelet Therapy (Aspirin, Clopidogrel and Dipyridamole) in the Secondary Prevention of Stroke: Safety, Tolerability and Feasibility  [PDF]
Nikola Sprigg, Laura J. Gray, Tim England, Mark R. Willmot, Lian Zhao, Gillian M. Sare, Philip M. W. Bath
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0002852
Abstract: Background Aspirin, dipyridamole and clopidogrel are effective in secondary vascular prevention. Combination therapy with three antiplatelet agents might maximise the benefit of antiplatelet treatment in the secondary prevention of ischaemic stroke. Methodology/Principal Findings A randomised, parallel group, observer-blinded phase II trial compared the combination of aspirin, clopidogrel and dipyridamole with aspirin alone. Adult patients with ischaemic stroke or transient ischaemic attack (TIA) within 5 years were included. The primary outcome was tolerability to treatment assessed as the number of patients completing randomised treatment. Recruitment was halted prematurely after publication of the ESPRIT trial (which confirmed that combined aspirin and dipyridamole is more effective than aspirin alone). 17 patients were enrolled: male 12 (71%), mean age 62 (SD 13) years, lacunar stroke syndrome 12 (71%), median stroke/TIA onset to randomisation 8 months. Treatment was discontinued in 4 of 9 (44%) patients receiving triple therapy vs. none of 8 taking aspirin (p = 0.08). One recurrent stroke occurred in a patient in the triple group who was noncompliant of all antiplatelet medications. The number of patients with adverse events and bleeding complications, and their severity, were significantly greater in the triple therapy group (p<0.01). Conclusions/Significance Long term triple antiplatelet therapy was asociated with a significant increase in adverse events and bleeding rates, and their severity, and a trend to increased discontinuations. However, the patients had a low risk of recurrence and future trials should focus on short term therapy in high risk patients characterised by a very recent event or failure of dual antiplatelet therapy. Trial Registration Controlled-Trials.com ISRCTN83673558
Is clopidogrel superior to aspirin in secondary prevention of vascular disease?
Ale Algra, Jan van Gijn
Trials , 2000, DOI: 10.1186/cvm-1-3-143
Abstract: A nice bottle of Graves arrived at our offices in early August 2000. The Dutch branch of Sanofi-Synthelabo sent this wine to collaborators of the Clopidogrel versus Aspirin in Patients at Risk of Ischaemic Events (CAPRIE) trial [1] to celebrate the regulation of reimbursement for clopidogrel in the Netherlands on 26 July. The official indication for this novel antiplatelet drug reads: 'secondary prevention in patients with atherosclerotic disease and proven aspirin sensitivity'. Sanofi-Synthelabo appealed against the limitation to patients intolerant to aspirin, but lost the lawsuit [2].What is the background of this legal quarrel? The cornerstone is clinical evidence from the CAPRIE trial, a ran-domised, blinded, international study [1]. Clopidogrel (75 mg daily) and aspirin (325 mg daily) were compared in the prevention of the composite outcome event 'vascular death, nonfatal stroke or nonfatal myocardial infarction'. Clopidogrel reduced the annual risk of such a vascular event from 5.83 to 5.32% in comparison with aspirin, corresponding to a relative risk reduction (RRR) of 8.7%. The 95% confidence interval just kept clear of the neutral value and ranged from 0.3 to 16.5%. The design of the study was based on the paradigm prevalent in the early 1990s: all clinical presentations of atherosclerotic disease should be regarded as different manifestations of a single disorder of the arterial vascular tree. The data of the CAPRIE trial do not necessarily support this paradigm, because the RRR values of the three diagnostic strata (each with over 6000 patients) differed considerably: -3.7% for myocardial infarction, +7.3% for ischaemic stroke, and 23.8% for peripheral arterial disease (P = 0.042). A similar difference between different categories of atherosclerotic disease had been observed by the AntiPlatelet Trialists' Collaboration [3]. The RRR values achieved by aspirin (compared with placebo) ranged from 18% for cerebral ischaemia to 35% for unstable angina.Clopido
Premorbid Use of Clopidogrel Portends Worse Outcomes in Patients Treated Surgically for Intracranial Hemorrhage  [PDF]
Eric Marvin, Aaron Danison, Greg Davis, Zev Elias, Gary Simonds
Open Journal of Modern Neurosurgery (OJMN) , 2014, DOI: 10.4236/ojmn.2014.44030
Abstract: Background: Widespread use of antiplatelet and anticoagulation medications (APACs) can be a difficult challenge in the presence of a neurosurgical emergency. Premorbid use of APACs, particularly clopidogrel, has been shown to affect outcomes in patients with stroke and traumatic brain injury. Objective: We hypothesized that pre-morbid clopidogrel use in patients with intracranial hemorrhage necessitating surgical intervention would lead to a greater risk of death and need for re-operation than those taking other APACs. Methods: Retrospective single institution review was conducted from January, 2010 through November, 2012 for intracranial hemorrhages necessitating surgical evacuation. Acute, subacute and chronic subdural, epidural and intraparenchymal hemorrhages were included. Results: 185 of 410 patients that required surgery for intracranial hemorrhage were on APACs. Overall mortality rate was 33%, with a 37% mortality rate in the APAC group. Overall reoperation rate was 7.5%, and 13% in the APAC group. Chi-square testing demonstrated significance between mortality and clopidogrel use (p = 0.0038), but not in APAC, warfarin or aspirin groups. There was statistical significance between the need for reoperation and APAC use (p = 0.002), aspirin use (p = 0.0097), and clopidogrel use (p = 0.0152), but not warfarin. Multivariate regression demonstrated only clopidogrel use is associated with higher mortality (p = 0.05) and need for reoperation (p = 0.0206). Conclusion: APAC use in the setting of intracranial hemorrhage necessitating surgical evacuation have higher intraoperative blood loss, need for transfusion and risk for adverse cardiac events. Premorbid clopidogrel use is associated with an increased risk in mortality and need for reoperation.
Benefit of addition of clopidogrel in addition to aspirin and fibrinolytic therapy in STEMI: an Indian data  [cached]
Abhilash Kannan,Rajasekharan Chandrasekharan,Radhakrishnan Vallikkattu Velayudhan
International Journal of Basic & Clinical Pharmacology , 2013, DOI: 10.5455/2319-2003.ijbcp20130825
Abstract: Background: The study was designed to find out whether the addition of clopidogrel for patients with ST- elevation myocardial infarction [STEMI] who are receiving a standard fibrinolytic therapy, including aspirin, reduce the incidence of primary and secondary end points like recurrent ischemia, re-infarction, need for urgent Target Vessel Revascularisation [TVR], mortality & bleeding. Methods: The patients were randomly assigned to receive the study medication. The patients were divided into two groups. Those receiving fibrinolytic therapy & aspirin were included in Group A. Those receiving the study drug in addition to aspirin & fibrinolytic agent were included in Group B. The study drug was given daily upto 1 month. These patients were assessed during their hospital stay & followed up for a period of 30 days for end points like recurrent ischemia, re-infarction, need for urgent TVR, bleeding episodes & mortality. Results: There was reduction in primary endpoints in group B compared to group A of which only reduction of recurrent ischemia was statistically significant (26% vs 2%). The same pattern of benefit was seen with secondary end points with significant reduction in recurrent ischemia in group B (28% vs 2%). Safety end points showed some increased bleeding in group B patients which was statistically insignificant (4% vs 0). Conclusion: Addition of Clopidogrel to aspirin and fibrinolytic therapy in ST-elevation MI showed a significant reduction in recurrent ischemia during in hospital stay and during the first 30 days. The patients received clopidogrel had less mortality compared to aspirin group. There were only minor bleeding episodes reported with use of clopidogrel. [Int J Basic Clin Pharmacol 2013; 2(4.000): 480-484]
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.