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1.
Expert Opin Drug Saf ; 19(3): 281-294, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32064957

RESUMO

Introduction: Drug-induced myocardial dysfunction is an important safety concern during drug development. Oncology compounds can cause myocardial dysfunction, leading to decreased left ventricular ejection fraction and heart failure via several mechanisms. Cardiovascular imaging has a major role in the early detection and monitoring of cardiotoxicity. Echocardiography is the method of choice because of its widespread availability, low cost, and absence of radiation exposure. Cardiac magnetic resonance imaging can provide better reliability, reproducibility, and accuracy in the detection of drug-induced myocardial dysfunction. In addition, it enables assessment of myocardial edema, fibrosis, and necrosis. Cardiac serologic biomarkers such as troponins and B-type natriuretic peptides are used in combination with imaging during drug development. This article provides a general overview of each imaging modality and practical guidance for early detection and monitoring of cardiotoxicity.Areas covered: Cardiovascular imaging modalities and cardiac biomarkers for monitoring of cardiac function and early detection of drug-induced myocardial dysfunction in drug development.Expert opinion: Some new drugs especially in the oncology field, can cause myocardial dysfunction. Depending on the strength of pre-clinical or clinical data, CV imaging modalities and cardiac biomarkers play an important role in the early detection and mitigation plans for such drugs during their development.


Assuntos
Antineoplásicos/efeitos adversos , Biomarcadores/sangue , Cardiotoxicidade/diagnóstico por imagem , Desenvolvimento de Medicamentos/métodos , Ecocardiografia/métodos , Imageamento por Ressonância Magnética/métodos , Animais , Cardiotoxicidade/sangue , Diagnóstico Precoce , Humanos
2.
Int J Cardiol ; 271: 247-253, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29898827

RESUMO

BACKGROUND: Statins are thought to have pleiotropic properties, including anticoagulant effects, in addition to reducing lipoprotein (LDL) levels. Plasma extracellular vesicles (EVs) are small bilayer membrane vesicles involved in various biological processes including coagulation. Since subsets of EVs in the LDL plasma fraction (LDL-EVs) correlate with thrombin activity, we hypothesized that changes in LDL-EVs after statin therapy may differ from that of serum levels of coagulation proteins, providing insight into the effects of statins on coagulation. METHODS: The study was conducted in 666 subjects with available serum from the METEOR trial, a trial of the effect of rosuvastatin versus placebo in patients with subclinical atherosclerosis. Changes in protein levels of von Willebrand Factor (VWF), SerpinC1 and plasminogen were measured in serum and in LDL-EVs, and were compared between the rosuvastatin and placebo groups. RESULTS: LDL-EV levels of plasminogen and VWF increased with rosuvastatin treatment compared to placebo (mean change of 126 ±â€¯8 versus 17 ±â€¯12 µg/mL for plasminogen (p < 0.001) and 310 ±â€¯60 versus 64 ±â€¯55 µg/mL for VWF (p = 0.015)). There was no difference between groups for change in LDL-EV-SerpinC1. In contrast, serum plasminogen levels increased to a lesser extent with rosuvastatin compared to placebo (23 ±â€¯29 versus 67 ±â€¯17 µg/mL, p = 0.024) and serum VWF levels showed no significant difference between both groups. CONCLUSIONS: Rosuvastatin increases LDL-EV coagulation proteins plasminogen and VWF in patients with subclinical atherosclerosis, an effect that is different from the effect of rosuvastatin on the same proteins in serum. This identifies LDL-EVs as a newly detected possible intermediate between statin therapy and coagulation.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , LDL-Colesterol/sangue , Vesículas Extracelulares/efeitos dos fármacos , Vesículas Extracelulares/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Rosuvastatina Cálcica/farmacologia , Coagulação Sanguínea/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasminogênio/metabolismo , Fator de von Willebrand/metabolismo
3.
J Am Coll Cardiol ; 70(9): 1162-1170, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28838366

RESUMO

BACKGROUND: Homozygous familial hypercholesterolemia (HoFH), a rare genetic disorder, is characterized by extremely elevated levels of low-density lipoprotein cholesterol (LDL-C) and accelerated atherosclerotic cardiovascular disease. Statin treatment starts at diagnosis, but no statin has been formally evaluated in, or approved for, HoFH children. OBJECTIVES: The authors sought to assess the LDL-C efficacy of rosuvastatin versus placebo in HoFH children, and the relationship with underlying genetic mutations. METHODS: This was a randomized, double-blind, 12-week, crossover study of rosuvastatin 20 mg versus placebo, followed by 12 weeks of open-label rosuvastatin. Patients discontinued all lipid-lowering treatment except ezetimibe and/or apheresis. Clinical and laboratory assessments were performed every 6 weeks. The relationship between LDL-C response and genetic mutations was assessed by adding children and adults from a prior HoFH rosuvastatin trial. RESULTS: Twenty patients were screened, 14 randomized, and 13 completed the study. The mean age was 10.9 years; 8 patients were on ezetimibe and 7 on apheresis. Mean LDL-C was 481 mg/dl (range: 229 to 742 mg/dl) on placebo and 396 mg/dl (range: 130 to 700 mg/dl) on rosuvastatin, producing a mean 85.4 mg/dl (22.3%) difference (p = 0.005). Efficacy was similar regardless of age or use of ezetimibe or apheresis, and was maintained for 12 weeks. Adverse events were few and not serious. Patients with 2 defective versus 2 negative LDL receptor mutations had mean LDL-C reductions of 23.5% (p = 0.0044) and 14% (p = 0.038), respectively. CONCLUSIONS: This first-ever pediatric HoFH statin trial demonstrated safe and effective LDL-C reduction with rosuvastatin 20 mg alone or added to ezetimibe and/or apheresis. The LDL-C response in children and adults was related to underlying genetic mutations. (A Study to Evaluate the Efficacy and Safety of Rosuvastatin in Children and Adolescents With Homozygous Familial Hypercholesterolemia [HYDRA]; NCT02226198).


Assuntos
LDL-Colesterol/genética , DNA/genética , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Mutação , Rosuvastatina Cálcica/administração & dosagem , Adolescente , Anticolesterolemiantes/administração & dosagem , Criança , LDL-Colesterol/sangue , Estudos Cross-Over , Análise Mutacional de DNA , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Homozigoto , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/genética , Masculino , Resultado do Tratamento
4.
Circulation ; 136(4): 359-366, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28592434

RESUMO

BACKGROUND: Heterozygous familial hypercholesterolemia (HeFH) is an autosomal dominant disorder leading to premature atherosclerosis. Children with HeFH exhibit early signs of atherosclerosis manifested by increased carotid intima-media thickness (IMT). In this study, we assessed the effect of 2-year treatment with rosuvastatin on carotid IMT in children with HeFH. METHODS: Children with HeFH (age, 6-<18 years) and low-density lipoprotein cholesterol >4.9 mmol/L or >4.1 mmol/L in combination with other risk factors received rosuvastatin for 2 years, starting at 5 mg once daily, with uptitration to 10 mg (age, 6-<10 years) or 20 mg (age, 10-<18 years). Carotid IMT was assessed by ultrasonography at baseline and 12 and 24 months in all patients and in age-matched unaffected siblings. Carotid IMT was measured at 3 locations (common carotid artery, carotid bulb, internal carotid artery) in both the left and right carotid arteries. A linear mixed-effects model was used to evaluate differences in carotid IMT between children with HeFH and the unaffected siblings. P values were adjusted for age, sex, carotid artery site, and family relations. RESULTS: At baseline, mean±SD carotid IMT was significantly greater for the 197 children with HeFH compared with the 65 unaffected siblings (0.397±0.049 and 0.377±0.045 mm, respectively; P=0.001). During 2 years of follow-up, the change in carotid IMT was 0.0054 mm/y (95% confidence interval, 0.0030-0.0082) in children with HeFH and 0.0143 mm/y (95% confidence interval, 0.0095-0.0192) in unaffected siblings (P=0.002). The end-of-study difference in mean carotid IMT between children with HeFH and unaffected siblings after 2 years was no longer significant (0.408±0.043 and 0.402±0.042 mm, respectively; P=0.2). CONCLUSIONS: In children with HeFH who were ≥6 years of age, carotid IMT was significantly greater at baseline compared with unaffected siblings. Rosuvastatin treatment for 2 years resulted in significantly less progression of increased carotid IMT in children with HeFH than untreated unaffected siblings. As a result, no difference in carotid IMT could be detected between the 2 groups after 2 years of rosuvastatin. These findings support the value of early initiation of statin treatment for low-density lipoprotein cholesterol reduction in children with HeFH. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01078675.


Assuntos
Anticolesterolemiantes/uso terapêutico , Espessura Intima-Media Carotídea/tendências , Heterozigoto , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Rosuvastatina Cálcica/uso terapêutico , Adolescente , Criança , Feminino , Seguimentos , Humanos , Masculino , Resultado do Tratamento
5.
Atherosclerosis ; 263: 137-144, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28641153

RESUMO

BACKGROUND & AIMS: Lipoprotein(a) [Lp(a)] is a low-density lipoprotein (LDL)-like particle that associates with major adverse cardiovascular events (MACE). We examined relationships between Lp(a) measurements and changes in coronary atheroma volume following long-term maximally-intensive statin therapy in coronary artery disease patients. METHODS: Study of coronary atheroma by intravascular ultrasound: Effect of Rosuvastatin Versus Atorvastatin (SATURN) used serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. Baseline and follow-up Lp(a) levels were measured in 915 of the 1039 SATURN participants, and were correlated with changes in percent atheroma volume (ΔPAV). RESULTS: Mean age was 57.7 ± 8.6 years, 74% were men, 96% were Caucasian, with statin use prior to study enrolment occurring in 59.3% of participants. Baseline [median (IQR)] LDL-cholesterol (LDL-C) and measured Lp(a) levels (mg/dL) were 114 (99, 137) and 17.4 (7.6, 52.9) respectively; follow-up measures were 60 (47, 77), and 16.5 (6.7, 57.7) (change from baseline: p < 0.001, p = 0.31 respectively). At baseline, there were 676 patients with Lp(a) levels <50 mg/dL [median Lp(a) of 10.9 mg/dL], and 239 patients with Lp(a) levels ≥ 50 mg/dL [median Lp(a) of 83.2 mg/dL]. Quartiles of baseline and follow-up Lp(a) did not associate with ΔPAV. Irrespective of the achieved LDL-C ( 50 mg/dL. CONCLUSIONS: In coronary artery disease patients prescribed long-term maximally intensive statin therapy with low on-treatment LDL-C levels, measured Lp(a) levels (predominantly below the 50 mg/dL threshold) do not associate with coronary atheroma progression. Alternative biomarkers may thus associate with residual cardiovascular risk in such patients.


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/fisiopatologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipoproteína(a)/sangue , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/fisiopatologia , Idoso , Atorvastatina/uso terapêutico , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Doença da Artéria Coronariana/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Modelos de Riscos Proporcionais , Rosuvastatina Cálcica/uso terapêutico , Ultrassonografia
6.
Expert Opin Drug Saf ; 16(2): 215-225, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27830951

RESUMO

INTRODUCTION: Changes in blood pressure (BP) are now proactively examined throughout the drug development process as an integral aspect of safety monitoring. This is because hypertension is a very strong risk factor for cardiovascular events and drug-induced increases in BP have attracted increased regulatory attention. However, there is currently no guidance from regulatory agencies on the minimum BP data required for submissions, and there are no specific criteria for what constitutes a safety signal for increased BP in non clinical studies. Areas covered: Evaluation of BP increases through the drug discovery and development process. Expert opinion: Research into the effects of drugs should begin before clinical development is initiated and continue throughout the clinical trial program. Non clinical studies should inform a benefit-risk analysis that will aid decision-making of whether to enter the drug into Phase I development. The degree of acceptable risk will vary according to the therapy area, treatment indication and intended population for the new drug, and the approach to BP assessment and risk mitigation should be tailored accordingly. However, BP monitoring should always be included in clinical trials, and data collected from multiple studies, to convincingly prove or refute a suspicion of BP effects.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Desenho de Fármacos , Hipertensão/induzido quimicamente , Animais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Ensaios Clínicos como Assunto/métodos , Humanos , Hipertensão/diagnóstico , Hipertensão/prevenção & controle , Medição de Risco/métodos , Fatores de Risco , Gestão de Riscos/métodos
7.
J Clin Lipidol ; 9(6): 741-750, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26687694

RESUMO

OBJECTIVE: Heterozygous familial hypercholesterolemia (HeFH) is an autosomal dominant disorder leading to premature atherosclerosis. Guidelines recommend initiating statins early to reduce low-density lipoprotein cholesterol (LDL-C). Studies have evaluated rosuvastatin in children aged ≥10 years, but its efficacy and safety in younger children is unknown. METHODS: Children with HeFH and fasting LDL-C >4.92 mmol/L (190 mg/dL) or >4.10 mmol/L (>158 mg/dL) with other cardiovascular risk factors received rosuvastatin 5 mg daily. Based on LDL-C targets (<2.85 mmol/L [<110 mg/dL]), rosuvastatin could be uptitrated to 10 mg (aged 6-9 years) or 20 mg (aged 10-17 years). Treatment lasted 2 years. Changes in lipid values, growth, sexual maturation, and adverse events (AEs) were assessed. RESULTS: The intention-to-treat analysis included 197 patients. At 24 months, LDL-C was reduced by 43, 45, and 35% vs baseline in patients aged 6-9, 10-13, and 14-17 years, respectively (P < .001 for all groups). Most AEs were mild. Intermittent myalgia was reported in 11 (6%) patients and did not lead to discontinuation of rosuvastatin treatment. Serious AEs were reported by 9 (5%) patients, all considered unrelated to treatment by the investigators. No clinically important changes in hepatic biochemistry were reported. Rosuvastatin treatment did not appear to adversely affect height, weight, or sexual maturation. CONCLUSIONS: In HeFH patients aged 6-17 years, rosuvastatin 5-20 mg over 2 years significantly reduced LDL-C compared with baseline. Treatment was well tolerated, with no adverse effects on growth or sexual maturation.


Assuntos
Hiperlipoproteinemia Tipo II/tratamento farmacológico , Rosuvastatina Cálcica/efeitos adversos , Rosuvastatina Cálcica/uso terapêutico , Segurança , Adolescente , Criança , LDL-Colesterol/sangue , Feminino , Humanos , Hiperlipoproteinemia Tipo II/sangue , Masculino , Rosuvastatina Cálcica/farmacocinética , Resultado do Tratamento
8.
JACC Cardiovasc Imaging ; 7(10): 1013-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25240453

RESUMO

OBJECTIVES: The study sought to explore sex-related differences in coronary atheroma regression following high-intensity statin therapy. BACKGROUND: Guidelines now recommend high-intensity statins in all individuals with atherosclerotic cardiovascular disease. METHODS: SATURN (Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin) employed serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. The treatment groups did not differ significantly in change from baseline of percent atheroma volume (PAV) or total atheroma volume (TAV) on intravascular ultrasound, nor in safety or clinical outcomes. RESULTS: Compared with men (n = 765), women (n = 274) were older (p < 0.001) and more likely to have hypertension (p < 0.001), diabetes (p = 0.002), and higher low-density lipoprotein cholesterol (LDL-C) (p = 0.01), high-density lipoprotein cholesterol (p < 0.001), and C-reactive protein (CRP) (p = 0.004) levels. At follow-up, women had higher high-density lipoprotein cholesterol (p < 0.001) and CRP (p < 0.001), but similar LDL-C (p = 0.46) levels compared with men. Compared with men, women had lower baseline PAV (34.0 ± 8.0% vs. 37.2 ± 8.2%, p < 0.001) and TAV (122.4 ± 55 mm(3) vs. 151.9 ± 63 mm(3), p < 0.001), yet demonstrated greater PAV regression (-1.52 ± 0.18% vs. -1.07 ± 0.10%, p = 0.03) and TAV regression (-8.27 ± 0.9 mm(3) vs. -6.59 ± 0.50 mm(3), p = 0.11) following treatment. Greater PAV regression in women versus men occurred with rosuvastatin (p = 0.004), those with diabetes (p = 0.01), stable coronary disease (p = 0.01), higher baseline LDL-C (p = 0.02), and higher CRP (p = 0.04) levels. On multivariable analysis, female sex was independently associated with PAV regression (p = 0.01), and a sex-treatment interaction was found (p = 0.036). For participants with on-treatment LDL-C levels <70 mg/dl, women achieved greater PAV regression (-1.81 ± 0.22% vs. -1.12 ± 0.13%, p = 0.007) and TAV regression (-10.1 ± 1.1 mm(3) vs. -7.16 ± 0.65 mm(3), p = 0.023) than men, whereas PAV and TAV regression did not differ by sex, with LDL-C levels ≥70 mg/dl. CONCLUSIONS: Women with coronary disease demonstrate greater coronary atheroma regression than men when empirically prescribed guideline-driven potent statin therapy. This benefit appears in the setting of lower on-treatment LDL-C levels. (CRESTOR Athero Imaging Head to Head IVUS Study [SATURN]; NCT000620542).


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/tratamento farmacológico , Fluorbenzenos/administração & dosagem , Ácidos Heptanoicos/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Pirimidinas/administração & dosagem , Pirróis/administração & dosagem , Sulfonamidas/administração & dosagem , Idoso , Atorvastatina , Proteína C-Reativa/análise , Comorbidade , Doença da Artéria Coronariana/epidemiologia , Angiopatias Diabéticas/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Rosuvastatina Cálcica , Fatores Sexuais , Ultrassonografia de Intervenção
9.
Arterioscler Thromb Vasc Biol ; 34(11): 2465-72, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25212234

RESUMO

OBJECTIVES: Patients with acute coronary syndromes (ACS) display diffuse coronary atheroma instability and heightened risk of early and late recurrent coronary events. We compared the long-term antiatherosclerotic efficacy of high-intensity statins in patients with ACS when compared with stable disease. APPROACH AND RESULTS: Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin (SATURN) used serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. The overall effect of high-intensity statins on the change in coronary percent atheroma volume and major adverse cardiovascular events (death/nonfatal myocardial infarction/coronary revascularization) were evaluated in this post hoc analysis. When compared with non-ACS patients (n=678), patients with ACS (n=361) were younger, actively smoking, and have had a previous myocardial infarction (all P<0.001). At baseline, patients with ACS exhibited lower high-density lipoprotein cholesterol (43.5±11 versus 45.8±11 mg/dL; P=0.002), a higher apolipoprotein B: apolipoprotein A-1 ratio (0.90±0.24 versus 0.83±0.24; P<0.001) and greater percent atheroma volume (37.3±8.5% versus 35.9±8.1%; P=0.01) when compared with non-ACS patients. Despite similar achieved levels of lipid and inflammatory markers after high-intensity statin therapy, patients with ACS demonstrated greater percent atheroma volume regression than non-ACS patients (-1.46±0.14 versus -0.89±0.13; P=0.003). After propensity-weighted multivariable adjustment, baseline percent atheroma volume (P<0.001) and an ACS clinical presentation (P=0.02) independently associated with plaque regression. The 24-month major adverse cardiovascular events-free survival was similar between patients with ACS and non-ACS (90.6 versus 92.9%; P=0.25). CONCLUSIONS: Long-term high-intensity statin therapy caused greater plaque regression and comparable major adverse cardiovascular events rates in ACS when compared with non-ACS patients. Despite a higher clinical risk profile, patients with ACS harbor a more modifiable disease substrate and seem to benefit the most from potent statin therapy.


Assuntos
Síndrome Coronariana Aguda/complicações , Anticolesterolemiantes/uso terapêutico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/prevenção & controle , Fluorbenzenos/uso terapêutico , Ácidos Heptanoicos/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Sulfonamidas/uso terapêutico , Idoso , Apolipoproteínas A/sangue , Apolipoproteínas B/sangue , Atorvastatina , HDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Rosuvastatina Cálcica , Resultado do Tratamento , Ultrassonografia
10.
Diabetes Care ; 37(11): 3114-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25190674

RESUMO

OBJECTIVE: Although statins can induce coronary atheroma regression, this benefit has yet to be demonstrated in diabetic individuals. We tested the hypothesis that high-intensity statin therapy may promote coronary atheroma regression in patients with diabetes. RESEARCH DESIGN AND METHODS: The Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin (SATURN) used serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. This analysis compared changes in biochemistry and coronary percent atheroma volume (PAV) in patients with (n = 159) and without (n = 880) diabetes. RESULTS: At baseline, patients with diabetes had lower LDL cholesterol (LDL-C) and HDL cholesterol (HDL-C) levels but higher triglyceride and CRP levels compared with patients without diabetes. At follow-up, diabetic patients had lower levels of LDL-C (61.0 ± 20.5 vs. 66.4 ± 22.9 mg/dL, P = 0.01) and HDL-C (46.3 ± 10.6 vs. 49.9 ± 12.0 mg/dL, P < 0.001) but higher levels of triglycerides (127.6 [98.8, 163.0] vs. 113.0 mg/dL [87.6, 151.9], P = 0.001) and CRP (1.4 [0.7, 3.3] vs. 1.0 [0.5, 2.1] mg/L, P = 0.001). Both patients with and without diabetes demonstrated regression of coronary atheroma as measured by change in PAV (-0.83 ± 0.13 vs. -1.15 ± 0.13%, P = 0.08). PAV regression was less in diabetic compared with nondiabetic patients when on-treatment LDL-C levels were >70 mg/dL (-0.31 ± 0.23 vs. -1.01 ± 0.21%, P = 0.03) but similar when LDL-C levels were ≤70 mg/dL (-1.09 ± 0.16 vs. -1.24 ± 0.16%, P = 0.50). CONCLUSIONS: High-intensity statin therapy alters the progressive nature of diabetic coronary atherosclerosis, yielding regression of disease in diabetic and nondiabetic patients.


Assuntos
Fluorbenzenos/uso terapêutico , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Placa Aterosclerótica/tratamento farmacológico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Sulfonamidas/uso terapêutico , Idoso , Atorvastatina , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/etiologia , Rosuvastatina Cálcica , Ultrassonografia de Intervenção
11.
Eur Heart J Cardiovasc Imaging ; 15(4): 380-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24448227

RESUMO

AIMS: To evaluate the effect of long-term maximally intensive statin therapy on indices of coronary atheroma composition in a randomized trial, and how these changes relate to modifications of serum lipoproteins and systemic inflammation. METHODS AND RESULTS: The Study of coronary Atheroma by inTravascular Ultrasound: the effect of Rosuvastatin vs. atorvastatiN (SATURN) employed serial intravascular ultrasound (IVUS) measures of coronary atheroma in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg daily for 24 months. Seventy-one patients underwent serial assessment of indices of plaque composition by spectral analysis of the radiofrequency IVUS signal. Changes in low-density lipoprotein cholesterol [LDL-C; -52 (-72, -33) mg/dL, P < 0.001], C-reactive protein [CRP -0.2 (-1, 0.1) mg/L, P = 0.01], and high-density lipoprotein cholesterol [HDL-C; +2.8 (-0.3, 7.8) mg/dL, P < 0.001] were associated with regression of percent atheroma volume (PAV: -1.6 ± 3.6%, P < 0.001). A reduction in estimated fibro-fatty tissue volume accompanied atheroma regression (P < 0.001), while dense calcium tissue volume increased (P = 0.002). There were no changes in fibrous or necrotic core tissue volumes. Volumetric changes in necrotic core tissue correlated with on-treatment HDL-C (r = -0.27, P = 0.03) and CRP (r = 0.25, P = 0.03) levels. A per-lesion analysis showed a reduction in the number of pathological intimal thickening lesions (defined by ≥3 consecutive IVUS frames containing PAV of ≥40%, predominantly fibro-fatty plaque, with <10% confluent necrotic core and <10% confluent dense calcium) at follow-up (67 vs. 38, P = 0.001). Fibroatheromas and fibrotic lesions remained static in number. CONCLUSIONS: Changes in indices of atheroma composition accompany regression of coronary atheroma with maximally intensive statin therapy, and associate with anti-inflammatory effects of statins. CLINICALTRAILSGOV NUMBER: NCT000620542.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Fluorbenzenos/uso terapêutico , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Placa Aterosclerótica/diagnóstico por imagem , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Sulfonamidas/uso terapêutico , Ultrassonografia de Intervenção , Idoso , Atorvastatina , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Fatores de Risco , Rosuvastatina Cálcica , Fatores de Tempo , Resultado do Tratamento , Túnica Íntima/diagnóstico por imagem , Túnica Íntima/efeitos dos fármacos , Ultrassonografia de Intervenção/métodos
12.
Circulation ; 128(22): 2395-403, 2013 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-24043299

RESUMO

BACKGROUND: Baseline C-reactive protein (CRP) levels predict major adverse cardiovascular events (MACE: death, myocardial infarction, stroke, coronary revascularization, and hospitalization for unstable angina). The association between changes in CRP levels with plaque progression and MACE in the setting of maximally intensive statin therapy is unknown. METHODS AND RESULTS: The Study of Coronary Atheroma by Intravascular Ultrasound: Effect of Rosuvastatin Versus Atorvastatin (SATURN) used serial intravascular ultrasound measures of coronary atheroma volume in patients treated with rosuvastatin 40 mg or atorvastatin 80 mg for 24 months. The treatment groups did not differ significantly in the change from baseline of percent atheroma volume on intravascular ultrasound, CRP-modulating effects, or MACE rates, thus allowing for a (prespecified) post hoc analysis to test associations between the changes in CRP levels with coronary disease progression and MACE. Patients with nonincreasing CRP levels (n=621) had higher baseline (2.3 [1.1-4.7] versus 1.1 [0.5-1.8] mg/L; P<0.001) and lower follow-up CRP levels (0.8 [0.5-1.7] versus 1.6 [0.7-4.1] mg/L; P<0.001) versus those with increasing CRP levels (n=364). Multivariable analysis revealed a nonincreasing CRP level to independently associate with greater percent atheroma volume regression (P=0.01). Although the (log) change in CRP did not associate with MACE (hazard ratio, 1.18; 95% confidence interval, 0.93-1.50; P=0.17), the (log) on-treatment CRP associated significantly with MACE (hazard ratio, 1.28; 95% confidence interval, 1.04-1.56; P=0.02). On-treatment low-density lipoprotein cholesterol levels did not correlate with MACE (hazard ratio, 1.09; 95% confidence interval, 0.88-1.35; P=0.45). CONCLUSIONS: Following 24 months of potent statin therapy, on-treatment CRP levels associated with MACE. Inflammation may be an important driver of residual cardiovascular risk in patients with coronary artery disease despite aggressive statin therapy. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov. Unique identifier: NCT000620542.


Assuntos
Proteína C-Reativa/metabolismo , LDL-Colesterol/metabolismo , Doença da Artéria Coronariana , Fluorbenzenos/administração & dosagem , Ácidos Heptanoicos/administração & dosagem , Lipoproteínas LDL/metabolismo , Pirimidinas/administração & dosagem , Pirróis/administração & dosagem , Sulfonamidas/administração & dosagem , Idoso , Atorvastatina , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/mortalidade , Feminino , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Rosuvastatina Cálcica
13.
Eur Heart J ; 34(41): 3182-90, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23886915

RESUMO

AIMS: The impact of baseline coronary plaque burden on the clinical outcome in patients receiving aggressive low-density lipoprotein cholesterol (LDL-C) lowering therapy to levels <70 mg/dL is unknown. We assessed the prognostic significance of baseline coronary plaque burden following high-intensity statin therapy. METHODS AND RESULTS: SATURN used serial intravascular ultrasound (IVUS) to measure coronary atheroma volume in 1039 patients before and after 24 months of treatment with rosuvastatin 40 mg or atorvastatin 80 mg. This post hoc analysis compared the relationship between baseline percent atheroma volume (PAV) and major adverse cardiovascular events (MACE: death, myocardial infarction, stroke, coronary revascularization, hospitalization for unstable angina) in patients with baseline PAV less than (n = 519) or greater than (n = 520) the median. Patients with a higher baseline PAV had a similar LDL-C compared with those with a lower baseline PAV at baseline (119.0 ± 29 vs. 121.0 ± 27 mg/dL, P = 0.09) and at follow-up (65.3 ± 23 vs. 65.8 ± 22 mg/dL, P = 0.47). In multivariable analysis, each standard deviation increase in baseline PAV was associated with a 28% increase in MACE [HR 1.28 (1.05, 1.57), P = 0.01]. Those with the highest quartile of baseline PAV (>41.8%) had a 2-year cumulative MACE rate of 12%, which was significantly higher (log-rank P = 0.001) than MACE rates of all lower PAV quartiles (MACE: quartile 3, 2, and 1 were 5.7, 7.9, and 5.1%, respectively). LDL-C levels at baseline [HR 0.96 (0.79, 1.18), P = 0.73] and on-treatment [HR 1.19 (0.83, 1.73), P = 0.35] were not associated with MACE. CONCLUSION: Following 2 years of high-intensity statin therapy, a baseline coronary atheroma volume predicted MACE, despite the achievement of very low on-treatment LDL-C levels.


Assuntos
Doença da Artéria Coronariana/patologia , Fluorbenzenos/administração & dosagem , Ácidos Heptanoicos/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Placa Aterosclerótica/patologia , Pirimidinas/administração & dosagem , Pirróis/administração & dosagem , Sulfonamidas/administração & dosagem , Angina Instável/etiologia , Atorvastatina , LDL-Colesterol/metabolismo , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/mortalidade , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Revascularização Miocárdica/estatística & dados numéricos , Placa Aterosclerótica/sangue , Placa Aterosclerótica/mortalidade , Rosuvastatina Cálcica , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento , Ultrassonografia de Intervenção
14.
Eur Heart J ; 34(24): 1818-25, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23644179

RESUMO

AIMS: Statins can inhibit the progression of coronary atherosclerosis. We aimed to characterize clinical factors that associate with differing measures of coronary atheroma volume following potent statin therapy. METHODS AND RESULTS: SATURN employed serial intravascular ultrasound (IVUS) to monitor changes in measures of coronary atheroma burden [total atheroma volume (TAV) and per cent atheroma volume (PAV)] in 1039 patients with coronary artery disease, treated with rosuvastatin (40 mg) or atorvastatin (80 mg) daily for 24 months. Rosuvastatin-treated patients demonstrated greater reductions in low-density lipoprotein cholesterol (LDL-C, 47 vs. 40%, P < 0.001) and greater increases in high-density lipoprotein cholesterol (HDL-C, 13 vs. 10%, P = 0.02). These alterations in the lipid profile associated with greater TAV (-6.4 vs. -4.4 mm(3), P = 0.01), but not PAV (-1.22 vs. -0.99%, P = 0.17) regression. Greater TAV reductions with rosuvastatin vs. atorvastatin occurred in patients with diabetes (P = 0.01, treatment by diabetic status interaction P-value 0.05). Greater PAV reductions with rosuvastatin were evident in females (P = 0.01, treatment by sex interaction P-value 0.03) and in those with greater than or equal to median baseline LDL-C (P = 0.02, treatment by LDL-C group interaction P-value 0.03) or HDL-C levels (P = 0.02, treatment by HDL-C group interaction P-value 0.04). On multivariable analysis assessing change in TAV and PAV, both higher baseline TAV and PAV independently associated with TAV and PAV regression, respectively (standardized estimates: TAV -0.25, P < 0.001; PAV -0.23, P < 0.001). CONCLUSION: Higher-risk patients, particularly those with greater baseline coronary atheroma volume, are more likely to experience less disease progression with potent statin therapy.


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Fluorbenzenos/uso terapêutico , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Placa Aterosclerótica/tratamento farmacológico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Sulfonamidas/uso terapêutico , Análise de Variância , Atorvastatina , HDL-Colesterol/efeitos dos fármacos , LDL-Colesterol/efeitos dos fármacos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Endossonografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Rosuvastatina Cálcica
15.
Am J Cardiol ; 111(4): 506-9, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23237107

RESUMO

The low-density lipoprotein (LDL) cholesterol goal of <70 mg/dl, recommended for patients with acute coronary syndrome, typically requires intensive therapy with high-dose statins. The secondary goals of non-high-density lipoprotein (non-HDL) cholesterol <100 mg/dl and apolipoprotein B (ApoB) <80 mg/dl have been recommended to reduce excess cardiovascular risk not captured by LDL cholesterol. The present post hoc analysis from the Limiting UNdertreatment of lipids in Acute coronary syndrome with Rosuvastatin (LUNAR) study examined the relation of ApoB with LDL cholesterol and non-HDL cholesterol at baseline and during treatment with intensive statin therapy. The LUNAR participants had acute coronary syndrome and received rosuvastatin 40 mg/day or 20 mg/day or atorvastatin 80 mg/day for 12 weeks. Linear regression analyses were used to compare ApoB, direct LDL cholesterol, and non-HDL cholesterol at baseline and during therapy. Of the 682 patients included in the analysis, 220 had triglycerides ≥200 mg/dl. Linear regression analysis showed that correlation of ApoB and non-HDL cholesterol was stronger than that of ApoB and LDL cholesterol and stronger with statin therapy than at baseline (R(2) = 0.93 for ApoB vs non-HDL cholesterol with statins). The target of ApoB of 80 mg/dl correlated with LDL cholesterol of 90 mg/dl and non-HDL cholesterol of 110 mg/dl at baseline and with LDL cholesterol of 74 mg/dl and non-HDL cholesterol of 92 mg/dl with statin therapy. For high-triglyceride patients, the corresponding on-treatment targets were LDL cholesterol of 68 mg/dl and non-HDL cholesterol of 92 mg/dl. In conclusion, non-HDL cholesterol is an adequate surrogate of ApoB during statin therapy, independent of triglyceride status. However, to match LDL cholesterol and ApoB treatment goals in the very-high-risk category, the current non-HDL cholesterol goal should be lowered by 8 to 10 mg/dl.


Assuntos
Síndrome Coronariana Aguda/sangue , Apolipoproteínas B/sangue , Colesterol/sangue , Fluorbenzenos/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Lipoproteínas/sangue , Pirimidinas/administração & dosagem , Sulfonamidas/administração & dosagem , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/etiologia , Idoso , Relação Dose-Resposta a Droga , Feminino , Fluorbenzenos/uso terapêutico , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/sangue , Hipercolesterolemia/complicações , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pirimidinas/uso terapêutico , Fatores de Risco , Rosuvastatina Cálcica , Sulfonamidas/uso terapêutico , Resultado do Tratamento
16.
Am Heart J ; 164(6): 846-55, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23194484

RESUMO

The ability to make informed benefit-risk assessments for potentially cardiotoxic new compounds is of considerable interest and importance at the public health, drug development, and individual patient levels. Cardiac imaging approaches in the evaluation of drug-induced myocardial dysfunction will likely play an increasing role. However, the optimal choice of myocardial imaging modality and the recommended frequency of monitoring are undefined. These decisions are complicated by the array of imaging techniques, which have varying sensitivities, specificities, availabilities, local expertise, safety, and costs, and by the variable time-course of tissue damage, functional myocardial depression, or recovery of function. This White Paper summarizes scientific discussions of members of the Cardiac Safety Research Consortium on the main factors to consider when selecting nonclinical and clinical cardiac function imaging techniques in drug development. We focus on 3 commonly used imaging modalities in the evaluation of cardiac function: echocardiography, magnetic resonance imaging, and radionuclide (nuclear) imaging and highlight areas for future research.


Assuntos
Técnicas de Imagem Cardíaca , Cardiomiopatias/diagnóstico , Fármacos Cardiovasculares/efeitos adversos , Cardiomiopatias/induzido quimicamente , Ecocardiografia , Humanos , Imageamento por Ressonância Magnética , Angiografia Cintilográfica , Medição de Risco
17.
J Am Soc Echocardiogr ; 25(10): 1120-1127.e1, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22884641

RESUMO

BACKGROUND: The echolucency of the carotid intima-media is related to increased cardiovascular risk factor levels, morbidity, and mortality. The aim of this study was to assess the effect of statins on the echolucency of the common carotid intima-media in a low-risk population. METHODS: Data from the Measuring Effects on Intima-Media Thickness: An Evaluation of Rosuvastatin study were used. Ultrasound images from the far walls of the left and right common carotid arteries were used for evaluation of the echolucency of the carotid intima-media, measured by grayscale median (GSM). Low GSM values reflect echolucent structures, whereas high values reflect echogenic structures. The primary end point was the difference in the annual rate of change in GSM between rosuvastatin and placebo. RESULTS: Two-year change in GSM did not significantly differ between rosuvastatin and placebo in the total population, with a mean difference in the rate of change in GSM of 1.13 (95% confidence interval, -1.00 to 3.25). The effect of rosuvastatin differed across quintiles of baseline GSM values (P for interaction = .01). In the lowest quintile (n = 175) (i.e., in those with the most echolucent intima-media), the difference in the rate of change in GSM between rosuvastatin and placebo was 4.18 (95% confidence interval, -0.23 to 8.58). Increases in GSM were significantly related to decreasing low-density lipoprotein cholesterol levels in the lowest quintile (ß = 0.76; 95% confidence interval, 0.26 to 1.25). CONCLUSIONS: Treatment with rosuvastatin did not affect the echolucency of the arterial wall in all low-risk individuals. However, a potential effect of rosuvastatin on the echolucency of the common carotid intima-media is most likely to be found in individuals with echolucent arterial walls at baseline.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/tratamento farmacológico , Espessura Intima-Media Carotídea , Ecocardiografia/métodos , Fluorbenzenos/uso terapêutico , Pirimidinas/uso terapêutico , Sulfonamidas/uso terapêutico , Doenças das Artérias Carótidas/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Fatores de Risco , Rosuvastatina Cálcica , Sensibilidade e Especificidade , Resultado do Tratamento
18.
Am J Physiol Heart Circ Physiol ; 303(1): H126-32, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22561300

RESUMO

Right heart catheterization is often required to monitor intra-cardiac pressures in a number of disease states. Ultrasound contrast agents can produce pressure modulated subharmonic emissions that may be used to estimate right ventricular (RV) pressures. A technique based on subharmonic acoustic emissions from ultrasound contrast agents to track RV pressures noninvasively has been developed and its clinical potential evaluated. The subharmonic signals were obtained from the aorta, RV, and right atrium (RA) of five anesthetized closed-chest mongrel dogs using a SonixRP ultrasound scanner and PA4-2 phased array. Simultaneous pressure measurements were obtained using a 5-French solid state micromanometer tipped catheter. Initially, aortic subharmonic signals and systemic blood pressures were used to obtain a calibration factor in units of millimeters of mercury per decibel. This factor was combined with RA pressures (that can be obtained noninvasively) and the acoustic data from the RV to obtain RV pressure values. The individual calibration factors ranged from -2.0 to -4.0 mmHg/dB. The subharmonic signals tracked transient changes in the RV pressures within an error of 0.6 mmHg. Relative to the catheter pressures, the mean errors in estimating RV peak systolic and minimum diastolic pressures, and RV relaxation [isovolumic negative derivative of change in pressure over time (-dP/dt)] by use of the subharmonic signals, were -2.3 mmHg, -0.8 mmHg, and 2.9 mmHg/s, respectively. Overall, acoustic estimates of RV peak systolic and minimum diastolic pressures and RV relaxation were within 3.4 mmHg, 1.8 mmHg, and 5.9 mmHg/s, respectively, of the measured pressures. This pilot study demonstrates that subharmonic emissions from ultrasound contrast agents have the potential to noninvasively track in vivo RV pressures with errors below 3.5 mmHg.


Assuntos
Determinação da Pressão Arterial/instrumentação , Microbolhas , Função Ventricular Direita/fisiologia , Animais , Aorta/fisiologia , Calibragem , Cateterismo Cardíaco , Meios de Contraste , Interpretação Estatística de Dados , Cães , Ecocardiografia/instrumentação , Ecocardiografia/métodos , Manometria/instrumentação , Projetos Piloto , Transdutores de Pressão , Pressão Ventricular
19.
Curr Med Res Opin ; 28(6): 891-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22536884

RESUMO

OBJECTIVE: Carotid intima-media thickness (CIMT) is a marker of atherosclerosis that is commonly used to assess the effect of therapeutic interventions. It is currently unclear to what extent biologically implausible values affect treatment effects. We evaluated the impact of biologically implausible CIMT values on the estimated rate of change in CIMT. METHODS: Data were used from the METEOR (Measuring Effects on Intima-media Thickness: an Evaluation of Rosuvastatin) trial. METEOR was a randomized, placebo-controlled trial showing that rosuvastatin reduced the 2-year change in CIMT among low-risk individuals with subclinical atherosclerosis. In the main METEOR analysis, the data were analyzed without exclusion of biologically implausible data. In this post-hoc analysis, we constructed twelve definitions to define mildly or extremely biologically implausible values using distance from the interquartile range, median or mean. We evaluated the effect of removing implausible values on the estimated rate of change in CIMT. RESULTS: The percentage of biologically implausible CIMT values ranged from 0.6% to 9.7%, depending on the definition used. Across all definitions, removal of biologically implausible CIMT values marginally reduced standard errors and did not change the primary outcome (i.e., a nonsignificant change in the rosuvastatin group, significant progression in the placebo group, and a statistically significant difference between treatment groups). LIMITATION: This study was focussed on the impact of implausible values in the analytical part of a CIMT study. Ultrasound images were not re-examined to determine whether an implausible measurement was due to measurement error or temporal morphological thickening, CONCLUSION: Removal of biologically implausible CIMT values marginally decreased the variability of the estimated rate of change in CIMT without having a large impact on the estimated rate of change.


Assuntos
Aterosclerose/diagnóstico , Espessura Intima-Media Carotídea , Túnica Íntima/patologia , Anticolesterolemiantes/uso terapêutico , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Espessura Intima-Media Carotídea/normas , Progressão da Doença , Método Duplo-Cego , Feminino , Fluorbenzenos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Valor Preditivo dos Testes , Pirimidinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Rosuvastatina Cálcica , Sulfonamidas/uso terapêutico , Fatores de Tempo
20.
Curr Med Res Opin ; 28(5): 681-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22439736

RESUMO

OBJECTIVE: Sample size calculations for clinical trials generally use expected changes between groups, and variances obtained from the literature. However, this approach neglects the impact of differences in trial design. We studied the effects of variations in trial design on the required sample size. METHODS: Data were used from the METEOR (Measuring Effects on Intima-Media Thickness: an Evaluation of Rosuvastatin) trial in which carotid intima-media thickness (CIMT) measurements were performed twice at baseline, at 6, 12 and 18 months, and twice at the end of 2-year study treatment. A sample size formula for continuous outcome measures that incorporates between- and within-individual variance components was used to evaluate the impact of differences in the length of follow-up, and the number of CIMT examinations. RESULTS: Trial designs with a shorter duration of follow-up have increased within-individual variance and require larger sample sizes to detect the same treatment effect. Reduction in the number of examinations within a trial with a given duration, i.e. by using single rather than duplicate baseline and end-of-study scans or by not performing intermediate scans, also increased the required sample size to maintain the same power. CONCLUSION: A longer trial duration and/or more frequent examinations within a trial which has repeated measures of an outcome variable substantially increase study power and reduce the required sample size. In situations where the costs of recruiting, retaining and examining individual participants are known, the sample size, study length and number of examinations can be balanced to optimize the trial design relative to costs or other study objectives.


Assuntos
Ensaios Clínicos como Assunto , Tamanho da Amostra , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Feminino , Fluorbenzenos , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pirimidinas , Ensaios Clínicos Controlados Aleatórios como Assunto , Rosuvastatina Cálcica , Sulfonamidas , Fatores de Tempo
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