Browsing by Subject "Ticlopidine"

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    Comparing Inverse Probability of Treatment Weighting and Instrumental Variable Methods for the Evaluation of Adenosine Diphosphate Receptor Inhibitors After Percutaneous Coronary Intervention.
    (JAMA cardiology, 2016-09) Federspiel, Jerome J; Anstrom, Kevin J; Xian, Ying; McCoy, Lisa A; Effron, Mark B; Faries, Douglas E; Zettler, Marjorie; Mauri, Laura; Yeh, Robert W; Peterson, Eric D; Wang, Tracy Y; Treatment With Adenosine Diphosphate Receptor Inhibitors–Longitudinal Assessment of Treatment Patterns and Events After Acute Coronary Syndrome (TRANSLATE-ACS) Investigators
    IMPORTANCE:There is increasing interest in performing comparative effectiveness analyses in large observational databases, yet these analyses must adjust for treatment selection issues. OBJECTIVES:To conduct comparative safety and efficacy analyses of prasugrel vs clopidogrel bisulfate after percutaneous coronary intervention and to evaluate inverse probability of treatment weighting (a propensity score method) and instrumental variable methods. DESIGN, SETTING, AND PARTICIPANTS:This study used data from the Treatment With Adenosine Diphosphate Receptor Inhibitors-Longitudinal Assessment of Treatment Patterns and Events After Acute Coronary Syndrome (TRANSLATE-ACS) study. Included in the study were patients undergoing percutaneous coronary intervention for myocardial infarction, 26.0% of whom received prasugrel. The study dates were April 4, 2010, to October 31, 2012. EXPOSURES:Choice of initial antiplatelet agent (prasugrel or clopidogrel). MAIN OUTCOMES AND MEASURES:Safety and efficacy outcomes included 1-year composite major adverse cardiovascular events, moderate to severe bleeding, and stent thrombosis. Hospitalizations for pneumonia, bone fractures, and planned percutaneous coronary intervention were used as the falsification end points. RESULTS:The study cohort comprised 11 784 participants (mean [SD] age, 60.0 [11.6] years, and 28.0% were female). Using inverse probability of treatment weighting adjustment, prasugrel and clopidogrel had similar major adverse cardiovascular events (hazard ratio [HR], 0.98; 95% CI, 0.83-1.16) and bleeding outcomes (1.18; 0.77-1.80), but prasugrel had a lower rate of stent thrombosis (0.51; 0.31-0.85). Using instrumental variable methods, prasugrel use was associated with a lower rate of the major adverse cardiovascular event end point (HR, 0.68; 95% CI, 0.47-1.00) but nonsignificant differences in the rates of bleeding (0.95; 0.41-2.08) and stent thrombosis (0.67; 0.16-2.00). There was no significant treatment difference noted in any of the falsification end-point rates when analyses were performed using inverse probability of treatment weighting, although the bone fracture end point approached statistical significance. Nevertheless, a lower rate of pneumonia-related hospitalizations was noted in the prasugrel-treated patients when analyses were performed using instrumental variable methods. CONCLUSIONS AND RELEVANCE:Conclusions regarding the safety and efficacy of antiplatelet therapy varied depending on analytic technique, and none were concordant with the results from randomized trials. In addition, both statistical strategies demonstrated concerning associations when tested in the falsification analyses. A high level of scrutiny and careful attention to assumptions and validity are required when interpreting complex analyses of observational data.
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    Early clopidogrel versus prasugrel use among contemporary STEMI and NSTEMI patients in the US: insights from the National Cardiovascular Data Registry.
    (J Am Heart Assoc, 2014-04-14) Sherwood, Matthew W; Wiviott, Stephen D; Peng, S Andrew; Roe, Matthew T; Delemos, James; Peterson, Eric D; Wang, Tracy Y
    BACKGROUND: P2Y12 antagonist therapy improves outcomes in acute myocardial infarction (MI) patients. Novel agents in this class are now available in the US. We studied the introduction of prasugrel into contemporary MI practice to understand the appropriateness of its use and assess for changes in antiplatelet management practices. METHODS AND RESULTS: Using ACTION Registry-GWTG (Get-with-the-Guidelines), we evaluated patterns of P2Y12 antagonist use within 24 hours of admission in 100 228 ST elevation myocardial infarction (STEMI) and 158 492 Non-ST elevation myocardial infarction (NSTEMI) patients at 548 hospitals between October 2009 and September 2012. Rates of early P2Y12 antagonist use were approximately 90% among STEMI and 57% among NSTEMI patients. From 2009 to 2012, prasugrel use increased significantly from 3% to 18% (5% to 30% in STEMI; 2% to 10% in NSTEMI; P for trend <0.001 for all). During the same period, we observed a decrease in use of early but not discharge P2Y12 antagonist among NSTEMI patients. Although contraindicated, 3.0% of patients with prior stroke received prasugrel. Prasugrel was used in 1.9% of patients ≥75 years and 4.5% of patients with weight <60 kg. In both STEMI and NSTEMI, prasugrel was most frequently used in patients at the lowest predicted risk for bleeding and mortality. Despite lack of supporting evidence, prasugrel was initiated before cardiac catheterization in 18% of NSTEMI patients. CONCLUSIONS: With prasugrel as an antiplatelet treatment option, contemporary practice shows low uptake of prasugrel and delays in P2Y12 antagonist initiation among NSTEMI patients. We also note concerning evidence of inappropriate use of prasugrel, and inadequate targeting of this more potent therapy to maximize the benefit/risk ratio.
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    Individual Proton Pump Inhibitors and Outcomes in Patients With Coronary Artery Disease on Dual Antiplatelet Therapy: A Systematic Review.
    (J Am Heart Assoc, 2015-10-29) Sherwood, Matthew W; Melloni, Chiara; Jones, W Schuyler; Washam, Jeffrey B; Hasselblad, Vic; Dolor, Rowena J
    BACKGROUND: Observational studies evaluating the possible interaction between proton pump inhibitors (PPIs) and clopidogrel have shown mixed results. We conducted a systematic review comparing the safety of individual PPIs in patients with coronary artery disease taking clopidogrel. METHODS AND RESULTS: Studies performed from January 1995 to December 2013 were screened for inclusion. Data were extracted, and study quality was graded for 34 potential studies. For those studies in which follow-up period, outcomes, and multivariable adjustment were comparable, meta-analysis was performed.The adjusted odds or hazard ratios for the composite of cardiovascular or all-cause death, myocardial infarction, and stroke at 1 year were reported in 6 observational studies with data on individual PPIs. Random-effects meta-analyses of the 6 studies revealed an increased risk for adverse cardiovascular events for those taking pantoprazole (hazard ratio 1.38; 95% CI 1.12-1.70), lansoprazole (hazard ratio 1.29; 95% CI 1.09-1.52), or esomeprazole (hazard ratio 1.27; 95% CI 1.02-1.58) compared with patients on no PPI. This association was not significant for omeprazole (hazard ratio 1.16; 95% CI 0.93-1.44). Sensitivity analyses for the coronary artery disease population (acute coronary syndrome versus mixed) and exclusion of a single study due to heterogeneity of reported results did not have significant influence on the effect estimates for any PPIs. CONCLUSIONS: Several frequently used PPIs previously thought to be safe for concomitant use with clopidogrel were associated with greater risk of adverse cardiovascular events. Although the data are observational, they highlight the need for randomized controlled trials to evaluate the safety of concomitant PPI and clopidogrel use in patients with coronary artery disease.
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    Lifetime cost-effectiveness analysis of ticagrelor in patients with acute coronary syndromes based on the PLATO trial: a Singapore healthcare perspective.
    (Singapore medical journal, 2013-03) Chin, Chee Tang; Mellstrom, Carl; Chua, Terrance Siang Jin; Matchar, David Bruce

    Introduction

    Ticagrelor is a novel antiplatelet drug developed to reduce atherothrombosis. The PLATO trial compared ticagrelor and aspirin to clopidogrel and aspirin in patients with acute coronary syndromes (ACS). Ticagrelor was found to be superior in the primary composite endpoint of cardiovascular death, myocardial infarction or stroke, without increasing major bleeding events. The current study estimates the lifetime cost-effectiveness of ticagrelor relative to generic clopidogrel from a Singapore public healthcare perspective.

    Methods

    This study used a two-part cost-effectiveness model. The first part was a 12-month decision tree (using PLATO trial data) to estimate the rates of major cardiovascular events, healthcare costs and health-related quality of life. The second part was a Markov model estimating lifetime quality-adjusted survival and costs conditional on events during the initial 12 months. Daily drug costs applied were SGD 1.05 (generic clopidogrel) and SGD 6.00 (ticagrelor). Cost per quality-adjusted life years (QALY) was estimated from a Singapore public healthcare perspective using life tables and short-term costs from Singapore, and long-term costs from South Korea. Deterministic and probabilistic sensitivity analyses were performed.

    Results

    Ticagrelor was associated with a lifetime QALY gain of 0.13, primarily driven by lower mortality. The resulting incremental cost per QALY gained was SGD 10,136.00. Probabilistic sensitivity analysis indicated that ticagrelor had a > 99% probability of being cost-effective, given the lower recommended WHO willingness-to-pay threshold of one GDP/capita per QALY.

    Conclusion

    Based on PLATO trial data, one-year treatment with ticagrelor versus generic clopidogrel in patients with ACS, relative to WHO reference standards, is cost-effective from a Singapore public healthcare perspective.
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    Outcomes According to Cardiac Catheterization Referral and Clopidogrel Use Among Medicare Patients With Non-ST-Segment Elevation Myocardial Infarction Discharged Without In-hospital Revascularization.
    (J Am Heart Assoc, 2016-03-14) Hess, Connie N; Hellkamp, Anne S; Roe, Matthew T; Thomas, Laine; Scirica, Benjamin M; Peng, S Andrew; Peterson, Eric D; Wang, Tracy Y
    BACKGROUND: While use of P2Y12 receptor inhibitor is recommended by guidelines, few studies have examined its effectiveness among older non-ST-segment elevation myocardial infarction patients who did not undergo coronary revascularization. METHODS AND RESULTS: We included unrevascularized non-ST-segment elevation myocardial infarction patients ≥65 years discharged home from 463 ACTION Registry-GWTG hospitals from 2007 to 2010. Rates of discharge clopidogrel use were described for patients with no angiography, angiography without obstructive coronary artery disease (CAD; ≥50% stenosis in ≥1 vessel), and angiography with obstructive CAD. Two-year outcomes were ascertained from linked Medicare data and included composite major adverse cardiac events (defined as all-cause death, myocardial infarction readmission, or revascularization), and individual components. Outcomes associated with clopidogrel use were adjusted using inverse probability-weighted propensity modeling. Of 14 154 unrevascularized patients, 54.7% (n=7745) did not undergo angiography, 10.6% (n=1494) had angiography without CAD, and 34.7% (n=4915) had angiography with CAD. Discharge clopidogrel was prescribed for 42.2% of all unrevascularized patients: 37.8% without angiography, 34.1% without obstructive CAD at angiography, and 51.6% with obstructive CAD at angiography. Discharge clopidogrel use was not associated with major adverse cardiac events in any group: without angiography (adjusted hazard ratio [95% CI]: 0.99 [0.93-1.06]), angiography without CAD (1.04 [0.74-1.47]), and angiography with CAD (1.12 [1.00-1.25], Pinteraction=0.20). CONCLUSIONS: We found no association between discharge clopidogrel use and long-term risk of major adverse cardiac events among older, unrevascularized non-ST-segment elevation myocardial infarction patients. Clopidogrel use in this population requires further prospective evaluation.
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    Outcomes of Patients with Critical Limb Ischaemia in the EUCLID Trial.
    (European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery, 2018-01) Norgren, Lars; Patel, Manesh R; Hiatt, William R; Wojdyla, Daniel M; Fowkes, F Gerry R; Baumgartner, Iris; Mahaffey, Kenneth W; Berger, Jeffrey S; Jones, W Schuyler; Katona, Brian G; Held, Peter; Blomster, Juuso I; Rockhold, Frank W; Björck, Martin; EUCLID Steering Committee and Investigators
    OBJECTIVES:Critical limb ischaemia (CLI) implies an increased risk of cardiovascular morbidity and mortality, and the optimal antithrombotic treatment is not established. DESIGN, MATERIALS, METHODS:The EUCLID trial investigated the effect of monotherapy with ticagrelor versus clopidogrel in 13,885 patients with peripheral artery disease (PAD); the primary endpoint was cardiovascular death, myocardial infarction, or ischaemic stroke. Patients planned for revascularisation or amputation within 3 months, were excluded. This analysis focuses on the subgroup with CLI, defined by rest pain (58.8%), major (9.0%) or minor (32.2%) tissue loss. RESULTS:In EUCLID, 643 patients (4.6%) had CLI at baseline. Diabetes mellitus was more common in the CLI group, while coronary disease, carotid disease, and hypertension were more common in the non-CLI group. A majority of CLI patients (62.1%) had only lower extremity PAD. In patients enrolled on the ankle brachial index (ABI) criteria, ABI was 0.55 ± 0.21 (mean ± SD) for those with CLI versus 0.63 ± 0.15 for those without CLI. The primary efficacy endpoint significantly increased among patients with CLI compared with those without CLI with a rate of 8.85 versus 4.28/100 patient years (adjusted for baseline characteristics hazard ratio [HR] 1.43 [95% CI 1.16-1.76]; p = 0.0009). When acute limb ischaemia requiring hospitalisation was added to the model, significant differences remained (adjusted HR 1.38, [95% CI 1.13-1.69]; p = 0.0016). The 1 year mortality was 8.9%. A trend towards increased lower limb revascularisation among those with CLI was observed. Bleeding (TIMI major, fatal, intracranial) did not differ between those with and without CLI. CONCLUSIONS:Nearly 5% of patients enrolled in EUCLID had CLI at baseline. Milder forms of CLI dominated, a result of the trial design. Patients with CLI had a significantly higher rate of cardiovascular mortality and morbidity versus those without CLI. Further efforts are required to reduce the risk of cardiovascular events in PAD, especially in patients with CLI. CLINICALTRIALS.GOV: NCT01732822.
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    Relationship of Platelet Reactivity With Bleeding Outcomes During Long-Term Treatment With Dual Antiplatelet Therapy for Medically Managed Patients With Non-ST-Segment Elevation Acute Coronary Syndromes.
    (Journal of the American Heart Association, 2016-11-04) Cornel, Jan H; Ohman, E Magnus; Neely, Benjamin; Jakubowski, Joseph A; Bhatt, Deepak L; White, Harvey D; Ardissino, Diego; Fox, Keith AA; Prabhakaran, Dorairaj; Armstrong, Paul W; Erlinge, David; Tantry, Udaya S; Gurbel, Paul A; Roe, Matthew T
    The relationship between "on-treatment" low platelet reactivity and longitudinal risks of major bleeding dual antiplatelet therapy following acute coronary syndromes remains uncertain, especially for patients who do not undergo percutaneous coronary intervention.We analyzed 2428 medically managed acute coronary syndromes patients from the Targeted Platelet Inhibition to Clarify the Optimal Strategy to Medically Manage Acute Coronary Syndromes (TRILOGY ACS) trial who had serial platelet reactivity measurements (P2Y12 reaction units; PRUs) and were randomized to aspirin+prasugrel versus aspirin+clopidogrel for up to 30 months. Contal's method was used to determine whether a cut point for steady-state PRU values could distinguish high versus low bleeding risk using 2-level composites: Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) severe/life-threatening or moderate bleeding unrelated to coronary artery bypass grafting (CABG) and non-CABG Thrombolysis In Myocardial Infarction (TIMI) major or minor bleeding. Exploratory analyses used 3-level composites that incorporated mild and minimal GUSTO and TIMI events. Continuous measures of PRUs (per 10-unit decrease) were not independently associated with the 2-level GUSTO (adjusted hazard ratio [HR], 1.01; 95% CI, 0.96-1.06) or TIMI composites (1.02; 0.98-1.07). Furthermore, no PRU cut point could significantly distinguish bleeding risk using the 2-level composites. However, the PRU cut point of 75 differentiated bleeding risk with the 3-level composites of GUSTO (26.5% vs 12.6%; adjusted HR, 2.28; 95% CI, 1.77-2.94; P<0.001) and TIMI bleeding events (25.9% vs 12.2%; adjusted HR, 2.30; 95% CI, 1.78-2.97; P<0.001).Among medically managed non-ST-segment elevation acute coronary syndromes patients receiving prolonged dual antiplatelet therapy, PRU values were not significantly associated with the long-term risk of major bleeding events, suggesting that low on-treatment platelet reactivity does not independently predict serious bleeding risk.URL: http://www.clinicaltrials.gov. Unique identifier: NCT00699998.
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    Treatment Effect of Clopidogrel Plus Aspirin Within 12 Hours of Acute Minor Stroke or Transient Ischemic Attack.
    (Journal of the American Heart Association, 2016-03-21) Li, Zixiao; Wang, Yilong; Zhao, Xingquan; Liu, Liping; Wang, David; Wang, Chunxue; Meng, Xia; Li, Hao; Pan, Yuesong; Wang, Xianwei; Wang, Chunjuan; Yang, Xiaomeng; Zhang, Changqing; Jing, Jing; Xian, Ying; Johnston, S Claiborne; Wang, Yongjun; CHANCE Investigators
    BACKGROUND:The aim of this study was to analyze the benefits and safety associated with the combination therapy of clopidogrel and aspirin among minor stroke or transient ischemic attack patients treated within 12 hours. METHODS AND RESULTS:This was a subanalysis of the CHANCE (Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events) trial, mainly limited to the prespecified group of patients randomized within 12 hours to either the combination of clopidogrel plus aspirin or aspirin alone. The primary outcome was ischemic stroke during 90-day follow-up. Recurrent ischemic stroke and progressive ischemic stroke were analyzed. Multivariable Cox modeling showed that randomization within 12 hours was an independent predictor of ischemic stroke events (hazard ratio [95% CI] 1.25 [1.04-1.49], P=0.02). Among 2573 patients randomized within 12 hours, 282 (10.96%) patients had ischemic stroke events. Among them, 158 (12.34%) of 1280 patients taking aspirin experienced ischemic stroke compared with 124 (9.59%) of 1293 patients taking clopidogrel-aspirin (P=0.02). The dual antiplatelet was more effective than aspirin alone in reducing the risk of recurrent ischemic stroke (6.57% versus 8.91%, P=0.03) but not progressive ischemic stroke (3.02% versus 3.43%, P=0.28). There was no significant difference in hemorrhagic events (P=0.39). CONCLUSIONS:Among patients treated within 12 hours, the combination of clopidogrel and aspirin was more effective than aspirin alone in reducing the risk of recurrent ischemic stroke during the 90-day follow-up and did not increase the hemorrhagic risk. CLINICAL TRIAL REGISTRATION:URL: https://www.clinicaltrials.gov/. Unique identifier: NCT00979589.