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1.
J Manag Care Spec Pharm ; 24(2): 142-152, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29384027

RESUMEN

BACKGROUND: Poor health outcomes after percutaneous coronary intervention (PCI) in elderly patients is an area of concern among policymakers and administrators. In an effort to determine the best strategy to improve outcomes among elderly patients who underwent PCI, several studies have evaluated the cost-effectiveness of genotype-guided antiplatelet therapy compared with universal use of any one of the antiplatelet drugs indicated for patients with acute coronary syndrome (ACS) who underwent PCI. The results have either been in favor of genotype-guided antiplatelet therapy or universal use of ticagrelor. However, no study has yet evaluated the cost-effectiveness of pharmacist-provided face-to-face medication therapy management (MTM) combined with point-of-care genotype-guided antiplatelet therapy (POCP) when compared with universal use of ticagrelor or clopidogrel for the elderly after PCI. OBJECTIVE: To evaluate the cost-effectiveness of a pharmacist integration of MTM with POCP (MTM-POCP) when compared with universal use of ticagrelor or clopidogrel combined with MTM (MTM-ticagrelor or MTM-clopidogrel). METHODS: We conducted a cost-effectiveness analysis from the perspective of the U.S. health care system. A hybrid model, consisting of a 1-year decision tree and a 20-year Markov model, was used to simulate a cohort of elderly patients (aged at least 65 years) with ACS who underwent PCI. Treatment strategies available to patients were POCP, POCP-MTM, MTM-clopidogrel, or MTM-ticagrelor. Data used to populate the model were obtained from the PLATO trial and other published studies. Outcome measures were costs, quality-adjusted life-years (QALYs) and incremental cost per QALY gained. A deterministic and probabilistic sensitivity analysis was conducted to account for the joint uncertainty around the key parameters of the model. Finally, a benchmark willingness to pay of $50,000-200,000 was considered. RESULTS: The use of PCOP (with dual antiplatelet therapy) resulted in 5.29 QALYs, at a cost of $50,207. MTM-clopidogrel resulted in 5.34 QALYs, at a cost of $50,011. The use of POCP-MTM resulted in 5.36 QALYs, at a cost of $50,270. Finally, MTM-ticagrelor resulted in 5.42 QALYs, at a cost of $53,346. MTM-ticagrelor was found to be cost-effective compared with MTM-clopidogrel or MTM-POCP, irrespective of the willingness to pay. The deterministic and probabilistic sensitivity analyses confirmed the robustness of the base-case analysis. CONCLUSIONS: The combination of MTM-ticagrelor was cost-effective when compared with MTM-POCP or MTM-clopidogrel. The transitional probabilities, however, were mostly based on published studies. Analysis based on a prospective randomized clinical study, comparing all the treatment strategies included in this study, is warranted to confirm our findings. DISCLOSURES: No outside funding supported this study. The authors have no conflicts of interest to declare. Study concept and design were contributed by Okere and Diaby. Ezendu took the lead in data collection, along with Okere. Data interpretation was performed by all the authors. The manuscript was written by Okere, Diaby, and Berthe and revised by Okere and Diaby.


Asunto(s)
Síndrome Coronario Agudo/terapia , Servicios Comunitarios de Farmacia/economía , Costos de los Medicamentos , Pruebas Genéticas/economía , Administración del Tratamiento Farmacológico/economía , Intervención Coronaria Percutánea/economía , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/economía , Pruebas en el Punto de Atención/economía , Medicina de Precisión/economía , Síndrome Coronario Agudo/sangre , Síndrome Coronario Agudo/economía , Síndrome Coronario Agudo/genética , Adenosina/administración & dosificación , Adenosina/análogos & derivados , Adenosina/economía , Factores de Edad , Anciano , Clopidogrel , Servicios Comunitarios de Farmacia/organización & administración , Simulación por Computador , Análisis Costo-Beneficio , Árboles de Decisión , Prestación Integrada de Atención de Salud/economía , Femenino , Humanos , Masculino , Cadenas de Markov , Administración del Tratamiento Farmacológico/organización & administración , Modelos Económicos , Intervención Coronaria Percutánea/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Pruebas en el Punto de Atención/organización & administración , Valor Predictivo de las Pruebas , Evaluación de Programas y Proyectos de Salud , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Ticagrelor , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados , Ticlopidina/economía , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
2.
Cardiovasc Drugs Ther ; 31(1): 39-49, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27924429

RESUMEN

PURPOSE: This study aimed to examine the cost-effectiveness of CYP2C19 loss-of-function and gain-of-function allele guided (LOF/GOF-guided) antiplatelet therapy in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). METHODS: A life-long decision-analytic model was designed to simulate outcomes of three strategies: universal clopidogrel (75 mg daily), universal alternative P2Y12 inhibitor (prasugrel 10 mg daily or ticagrelor 90 mg twice daily), and LOF/GOF-guided therapy (LOF/GOF allele carriers receiving alternative P2Y12 inhibitor, wild-type patients receiving clopidogrel). Model outcomes included clinical event rates, quality-adjusted life-years (QALYs) gained and direct medical costs from perspective of US healthcare provider. RESULTS: Base-case analysis found nonfatal myocardial infarction (5.62%) and stent thrombosis (1.2%) to be the lowest in universal alternative P2Y12 inhibitor arm, whereas nonfatal stroke (0.72%), cardiovascular death (2.42%), and major bleeding (2.73%) were lowest in LOF/GOF-guided group. LOF/GOF-guided arm gained the highest QALYs (7.5301 QALYs) at lowest life-long cost (USD 76,450). One-way sensitivity analysis showed base-case results were subject to the hazard ratio of cardiovascular death in carriers versus non-carriers of LOF allele and hazard ratio of cardiovascular death in non-carriers of LOF allele versus general patients. In probabilistic sensitivity analysis of 10,000 Monte Carlo simulations, LOF/GOF-guided therapy, universal alternative P2Y12 inhibitor, and universal clopidogrel were the preferred strategy (willingness-to-pay threshold = 50,000 USD/QALY) in 99.07%, 0.04%, and 0.89% of time, respectively. CONCLUSIONS: Using both CYP2C19 GOF and LOF alleles to select antiplatelet therapy appears to be the preferred antiplatelet strategy over universal clopidogrel and universal alternative P2Y12 inhibitor therapy for ACS patients with PCI.


Asunto(s)
Síndrome Coronario Agudo/economía , Síndrome Coronario Agudo/terapia , Citocromo P-450 CYP2C19/genética , Costos de los Medicamentos , Intervención Coronaria Percutánea/economía , Pruebas de Farmacogenómica/economía , Variantes Farmacogenómicas , Inhibidores de Agregación Plaquetaria/economía , Inhibidores de Agregación Plaquetaria/uso terapéutico , Antagonistas del Receptor Purinérgico P2Y/economía , Antagonistas del Receptor Purinérgico P2Y/uso terapéutico , Síndrome Coronario Agudo/enzimología , Síndrome Coronario Agudo/genética , Adenosina/análogos & derivados , Adenosina/economía , Adenosina/uso terapéutico , Clopidogrel , Simulación por Computador , Trombosis Coronaria/economía , Trombosis Coronaria/etiología , Análisis Costo-Beneficio , Citocromo P-450 CYP2C19/metabolismo , Técnicas de Apoyo para la Decisión , Genotipo , Hemorragia/inducido químicamente , Hemorragia/economía , Humanos , Modelos Económicos , Método de Montecarlo , Infarto del Miocardio/economía , Infarto del Miocardio/etiología , Selección de Paciente , Fenotipo , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/metabolismo , Clorhidrato de Prasugrel/economía , Clorhidrato de Prasugrel/uso terapéutico , Valor Predictivo de las Pruebas , Antagonistas del Receptor Purinérgico P2Y/efectos adversos , Antagonistas del Receptor Purinérgico P2Y/metabolismo , Años de Vida Ajustados por Calidad de Vida , Factores de Riesgo , Accidente Cerebrovascular/economía , Accidente Cerebrovascular/etiología , Ticagrelor , Ticlopidina/análogos & derivados , Ticlopidina/economía , Ticlopidina/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
3.
Cardiovasc Drugs Ther ; 28(1): 87-98, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24048510

RESUMEN

PURPOSE: To compare the lifetime cost and effectiveness of five alternative chronic atrial fibrillation (AF) management strategies: rivaroxaban, warfarin, aspirin plus clopidogrel, aspirin and no prevention. METHODS: An individual-level state-transition model was developed to track the lifetime disease course associated with AF. The clinical and utility data were derived from published studies. The cost data were estimated based on local charges and current Chinese practices. Sensitivity analyses were used to explore the impact of uncertainty on the results. RESULTS: For base-case patients with a CHADS2 score of 3, the cost per additional quality-adjusted life-years (QALYs) gained for rivaroxaban compared with no prevention, aspirin, aspirin plus clopidogrel and warfarin was $116,884, $153,944, $155,979 and $216,273, respectively. CHADS2 score had a substantial impact on the model outcomes for different prevention strategies. The time distribution of warfarin international normalised ratio (INR), stroke and intracranial haemorrhage (ICH) risks, cost of rivaroxaban and utility of warfarin therapy had substantial impacts on the results. Based on a willingness-to-pay threshold of $16,350/QALY, no prevention strategy was the preferred therapy for a patient with a low risk for stroke and a high risk for ICH; aspirin was preferred for patients with a moderate risk for stroke and ICH; and warfarin was preferred for patients with a high risk for stroke and a low risk of ICH. CONCLUSION: In the context of limited health resources, rivaroxaban is unlikely to be cost-effective, although it provided more health benefits comparing with other strategies. Additionally, warfarin with good INR control might be more suitable for AF patients in developing regions.


Asunto(s)
Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Accidente Cerebrovascular/prevención & control , Anticoagulantes/economía , Aspirina/administración & dosificación , Aspirina/economía , Aspirina/uso terapéutico , Fibrilación Atrial/economía , China , Clopidogrel , Análisis Costo-Beneficio , Quimioterapia Combinada , Humanos , Modelos Económicos , Morfolinas/economía , Morfolinas/uso terapéutico , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/economía , Años de Vida Ajustados por Calidad de Vida , Factores de Riesgo , Rivaroxabán , Accidente Cerebrovascular/economía , Tiofenos/economía , Tiofenos/uso terapéutico , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados , Ticlopidina/economía , Ticlopidina/uso terapéutico , Warfarina/economía , Warfarina/uso terapéutico
4.
Am J Cardiol ; 109(7): 1020-5, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22221944

RESUMEN

Guidelines for atrial fibrillation (AF) recommend clopidogrel plus aspirin as an alternative stroke prevention strategy in patients in whom warfarin is unsuitable. A Markov model was conducted from a Medicare prospective using data from the Atrial Fibrillation Clopidogrel Trial with Irbesartan for Prevention of Vascular Events-A (ACTIVE-A) trial and other published studies. Base-case analysis evaluated patients 65 years old with AF, a CHADS(2) (congestive heart failure, 1 point; hypertension defined as blood pressure consistently >140/90 mm Hg or antihypertension medication, 1 point; age ≥75 years, 1 point; diabetes mellitus, 1 point; previous stroke or transient ishemic attack, 2 points) score of 2, and a lower risk for major bleeding. Patients received clopidogrel 75 mg/day plus aspirin or aspirin alone. Patients were followed for up to 35 years. Outcomes included quality-adjusted life-years (QALYs), costs (in 2011 American dollars), and incremental cost-effectiveness ratios. Quality-adjusted life expectancy and costs were 9.37 QALYs and $88,751 with clopidogrel plus aspirin and 9.01 QALYs and $79,057 with aspirin alone. Incremental cost-effectiveness ratio for clopidogrel plus aspirin was $26,928/QALY. With 1-way sensitivity analysis using a willingness-to-pay threshold of $50,000/QALY, clopidogrel plus aspirin was no longer cost effective when the CHADS(2) score was ≤1, major bleeding risk with aspirin was ≥2.50%/patient-year, the relative risk decrease for ischemic stroke with clopidogrel plus aspirin versus aspirin alone was <25%, and the utility of being healthy with AF on combination therapy decreased to 0.95. Monte Carlo simulation demonstrated that clopidogrel plus aspirin was cost effective in 55% and 73% of 10,000 iterations assuming willingness-to-pay thresholds of $50,000 and $100,000/QALY. In conclusion, clopidogrel plus aspirin appears cost-effective compared to aspirin alone for stroke prevention in patients with AF with a CHADS(2) of ≥2 and a lower risk of bleeding.


Asunto(s)
Aspirina/economía , Fibrilación Atrial/economía , Inhibidores de Agregación Plaquetaria/economía , Accidente Cerebrovascular/economía , Ticlopidina/análogos & derivados , Anciano , Anticoagulantes/economía , Aspirina/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/mortalidad , Ensayos Clínicos como Asunto , Clopidogrel , Estudios de Cohortes , Simulación por Computador , Análisis Costo-Beneficio , Quimioterapia Combinada , Estudios de Seguimiento , Humanos , Cadenas de Markov , Medicare/economía , Método de Montecarlo , Inhibidores de Agregación Plaquetaria/uso terapéutico , Años de Vida Ajustados por Calidad de Vida , Proyectos de Investigación , Factores de Riesgo , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/prevención & control , Tasa de Supervivencia , Ticlopidina/economía , Ticlopidina/uso terapéutico , Resultado del Tratamiento , Estados Unidos/epidemiología , Warfarina/economía
5.
J Cardiovasc Nurs ; 24(5): 371-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19707097

RESUMEN

BACKGROUND: Despite the importance of secondary prevention, nonadherence rates for patients with myocardial infarction (MI) range from 13% to 60% for prescribed, evidence-based medicines. Although rates and consequences of discontinuance vary for different medications, the existing literature provides little insight into reasons for discontinuance. OBJECTIVE: To address this gap, we explored clopidogrel and cholesterol-lowering therapy (CLT) discontinuance after an MI to understand patients' reasons for stopping these 2 medications. METHODS: In this qualitative descriptive study, 2 groups of patients who stopped a heart medication-either clopidogrel or CLT-were recruited from a prospective MI registry. Patients who discontinued CLT (n = 29) or clopidogrel (n = 11) were interviewed within 18 months of hospitalization. Patients were recruited and interviewed until data saturation was achieved. The Health Belief Model was used as an organizing framework in analyzing and coding the narrative data. The codes were then summarized for each group and compared to identify similarities and differences in reasons for CLT and clopidogrel discontinuance. RESULTS AND CONCLUSIONS: The most common reason for CLT discontinuance was adverse effects that were painful and interfered with daily life. Less common reasons for discontinuance were prescription confusion, cost, mistrust in medicines/healthcare system, and preference for alternative therapies. Reasons for clopidogrel discontinuance were duration confusion, adverse effects, and cost. Although doctors stopped patients' clopidogrel in preparation for surgery, doctors conceded to discontinuance of CLT for patients who experienced adverse effects after trying 2 to 3 different CLTs. Patients who discontinued CLT were more likely to believe that they did not need the treatment than do patients who discontinued clopidogrel. Clinicians should be aware that reasons may vary across patients and medication class for prematurely stopping therapy; thus, proactive interventions should be targeted to address these differences. Identifying at-risk patients for targeted interventions to prevent premature cardiac medication discontinuation is vital.


Asunto(s)
Cumplimiento de la Medicación/psicología , Motivación , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/psicología , Anciano , Anticolesterolemiantes/efectos adversos , Anticolesterolemiantes/economía , Clopidogrel , Femenino , Humanos , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Modelos Psicológicos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/mortalidad , Narración , Evaluación en Enfermería , Investigación Metodológica en Enfermería , Educación del Paciente como Asunto , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/economía , Investigación Cualitativa , Medición de Riesgo , Encuestas y Cuestionarios , Ticlopidina/efectos adversos , Ticlopidina/análogos & derivados , Ticlopidina/economía , Estados Unidos/epidemiología
7.
Health Technol Assess ; 8(40): iii-iv, xv-xvi, 1-141, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15461878

RESUMEN

OBJECTIVES: To review systematically the clinical effectiveness and the cost-effectiveness of clopidogrel used in combination with standard therapy including aspirin, compared with standard therapy alone for the treatment of non-ST-segment elevation acute coronary syndromes (ACS). DATA SOURCES: Electronic databases. Manufacturers' submissions. REVIEW METHODS: Studies were selected using rigorous criteria. The quality of randomised controlled trials (RCTs) was assessed according to criteria based on NHS CRD Report No. 4, and the quality of systematic reviews was assessed according to the guidelines for the Database of Reviews of Effect (DARE) criteria. The quality of economic evaluations was assessed according to a specifically tailored checklist. The clinical effectiveness and cost-effectiveness of clopidogrel in combination with standard therapy compared with standard therapy alone were synthesised through a narrative review with full tabulation of the results of the included studies. In the economic evaluations, a cost-effectiveness model was constructed using the best available evidence to determine cost-effectiveness in a UK setting. RESULTS: One RCT (the CURE trial) was a randomised, double-blind, placebo-controlled trial of high quality and showed that clopidogrel in addition to aspirin was significantly more effective than placebo plus aspirin in patients with non-ST-segment elevation ACS for the composite outcome of death from cardiovascular causes, non-fatal myocardial infarction or stroke over the 9-month treatment period. However, clopidogrel was associated with a significantly higher number of episodes of both major and minor bleeding. The results from the five systematic reviews that assessed the adverse events associated with long-term aspirin use showed that aspirin was associated with a significantly higher incidence of haemorrhagic stroke, extracranial haemorrhage and gastrointestinal haemorrhage compared with placebo. Of the cost-effectiveness evidence reviewed, only the manufacturer's submission was considered relevant from the perspective of the NHS. The review of this evidence highlighted potential limitations within the submission in its use of data and in the model structure used. These limitations led to the development of a new model with the aim of providing a more reliable estimate of the cost-effectiveness from the perspective of the UK NHS. This model indicated that clopidogrel appears cost-effective compared with standard care alone in patients with non-ST-elevation ACS as long as the NHS is willing to pay GBP6078 per quality of life year (QALY). The results were most sensitive to the inclusion of additional strategies that assessed alternative treatment durations with clopidogrel. Although treatment with clopidogrel for 12 months remained cost-effective for the overall cohort, provisional findings indicate that the shorter treatment durations may be more cost-effective in patients at low risk. CONCLUSIONS: The results of the CURE trial indicate that clopidogrel in combination with aspirin was significantly more effective than placebo combined with aspirin in a wide range of patients with ACS. This benefit was largely related to a reduction in Q-wave myocardial infarction. There was no statistically significant benefit in relation to mortality. The trial data suggested that a substantial part of the benefit derived from clopidogrel is achieved by 3 months, with a further small benefit over the remaining 9 months of chronic treatment. The results from the base-case model suggest that treatment with clopidogrel as an adjunct to standard therapy (including aspirin) for 12 months, compared with standard therapy alone, is cost-effective in non-ST elevation ACS patients as long as the health service is willing to pay GBP6078 per additional QALY. However, although treatment with clopidogrel for 12 months remained cost-effective for the overall cohort, provisional findings indicate that the shorter treatment durations may be more cost-effective in patients at low risk. To estimate the exact length of time that clopidogrel in addition to standard therapy should be prescribed for patients with non-ST-segment ACS would require a prospective trial that randomised patients to various durations of therapy. This would accurately assess whether a 'rebound' phenomenon occurs in patients if clopidogrel were stopped after 3 months of treatment.


Asunto(s)
Aspirina/uso terapéutico , Enfermedad Coronaria/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Enfermedad Aguda , Aspirina/economía , Clopidogrel , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/economía , Análisis Costo-Beneficio , Quimioterapia Combinada , Electrocardiografía , Humanos , Inhibidores de Agregación Plaquetaria/economía , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Ticlopidina/economía , Resultado del Tratamiento
8.
Herz ; 28(1): 65-71, 2003 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-12650165

RESUMEN

Although the combined use of acetylsalicylic acid (ASA) and clopidogrel represents the standard in the 4-week treatment after coronary stent implantation, a discussion persists in Germany regarding clopidogrel use and the actual measures for cost containment in the healthcare system. Indeed, clopidogrel has not been approved in Germany for use after stent im-plantation. The prescription of clopidogrel in this context is thus considered off-label use. Consequently, patients with social healthcare insurance should pay for clopidogrel out of their own pockets. This regimen, however, bears the inherent risk that patients will not purchase the drug and thus not take it. This overview article describes the risk to patients when social healthcare insurance companies would not pay for clopidogrel after coronary stent implantation. Five international, prospective, randomized and control-led studies in 3,230 patients have shown that "double" antiaggregation, i.e. a combination of ASA and the thienopyridin derivative ticlopidin, compared with ASA alone clearly reduced death, myocardial infarction and the need for another PCI or CABG to a manifold extent. Due to its lower rate of side effects, clopidogrel has replaced ticlopidin since mid-1998. The clinical results of three prospective, randomized studies and seven single-center registries in approximately 14,000 patients have shown that the combination of ASA and clopidogrel results not only in a lower rate of side effects, but also in a significant rate reduction of cardiovascular events of ca. 50% (from 4.0% to 2.1%). Therefore, the combined use of ASA and clopidogrel should be prescribed to avoid (sub)acute stent thrombosis --even if this is not according to the rules of the German healthcare system. The threat of fines to physicians prescribing clopdiogrel at the expense of the social health care insurance is counterproductive and jeopardizes the life of the patients.


Asunto(s)
Reestenosis Coronaria/prevención & control , Estenosis Coronaria/tratamiento farmacológico , Aprobación de Drogas , Drogas en Investigación/uso terapéutico , Stents , Ticlopidina/uso terapéutico , Aspirina/uso terapéutico , Clopidogrel , Aprobación de Drogas/legislación & jurisprudencia , Costos de los Medicamentos/legislación & jurisprudencia , Prescripciones de Medicamentos/economía , Quimioterapia Combinada , Drogas en Investigación/economía , Financiación Personal/economía , Financiación Personal/legislación & jurisprudencia , Alemania , Humanos , Programas Nacionales de Salud/economía , Programas Nacionales de Salud/legislación & jurisprudencia , Ensayos Clínicos Controlados Aleatorios como Asunto , Ticlopidina/análogos & derivados , Ticlopidina/economía , Resultado del Tratamiento
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