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BACKGROUND: Randomization is the foundation of any clinical trial involving treatment comparison. It helps mitigate selection bias, promotes similarity of treatment groups with respect to important known and unknown confounders, and contributes to the validity of statistical tests. Various restricted randomization procedures with different probabilistic structures and different statistical properties are available. The goal of this paper is to present a systematic roadmap for the choice and application of a restricted randomization procedure in a clinical trial. METHODS: We survey available restricted randomization procedures for sequential allocation of subjects in a randomized, comparative, parallel group clinical trial with equal (1:1) allocation. We explore statistical properties of these procedures, including balance/randomness tradeoff, type I error rate and power. We perform head-to-head comparisons of different procedures through simulation under various experimental scenarios, including cases when common model assumptions are violated. We also provide some real-life clinical trial examples to illustrate the thinking process for selecting a randomization procedure for implementation in practice. RESULTS: Restricted randomization procedures targeting 1:1 allocation vary in the degree of balance/randomness they induce, and more importantly, they vary in terms of validity and efficiency of statistical inference when common model assumptions are violated (e.g. when outcomes are affected by a linear time trend; measurement error distribution is misspecified; or selection bias is introduced in the experiment). Some procedures are more robust than others. Covariate-adjusted analysis may be essential to ensure validity of the results. Special considerations are required when selecting a randomization procedure for a clinical trial with very small sample size. CONCLUSIONS: The choice of randomization design, data analytic technique (parametric or nonparametric), and analysis strategy (randomization-based or population model-based) are all very important considerations. Randomization-based tests are robust and valid alternatives to likelihood-based tests and should be considered more frequently by clinical investigators.
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Distribución Aleatoria , Simulación por Computador , Humanos , Funciones de Verosimilitud , Tamaño de la Muestra , Sesgo de SelecciónRESUMEN
OBJECTIVES: To compare the effects of rituximab versus placebo on salivary gland ultrasound (SGUS) in primary Sjögren's syndrome (PSS) in a multicentre, multiobserver phase III trial substudy. METHODS: Subjects consenting to SGUS were randomised to rituximab or placebo given at weeks 0, 2, 24 and 26, and scanned at baseline and weeks 16 and 48. Sonographers completed a 0-11 total ultrasound score (TUS) comprising domains of echogenicity, homogeneity, glandular definition, glands involved and hypoechoic foci size. Baseline-adjusted TUS values were analysed over time, modelling change from baseline at each time point. For each TUS domain, we fitted a repeated-measures logistic regression model to model the odds of a response in the rituximab arm (≥1-point improvement) as a function of the baseline score, age category, disease duration and time point. RESULTS: 52 patients (n=26 rituximab and n=26 placebo) from nine centres completed baseline and one or more follow-up visits. Estimated between-group differences (rituximab-placebo) in baseline-adjusted TUS were -1.2 (95% CI -2.1 to -0.3; P=0.0099) and -1.2 (95% CI -2.0 to -0.5; P=0.0023) at weeks 16 and 48. Glandular definition improved in the rituximab arm with an OR of 6.8 (95% CI 1.1 to 43.0; P=0.043) at week 16 and 10.3 (95% CI 1.0 to 105.9; P=0.050) at week 48. CONCLUSIONS: We demonstrated statistically significant improvement in TUS after rituximab compared with placebo. This encourages further research into both B cell depletion therapies in PSS and SGUS as an imaging biomarker. TRIAL REGISTRATION NUMBER: 65360827, 2010-021430-64; Results.
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Factores Inmunológicos/uso terapéutico , Rituximab/uso terapéutico , Glándulas Salivales/efectos de los fármacos , Síndrome de Sjögren/tratamiento farmacológico , Ultrasonografía/métodos , Adulto , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Glándulas Salivales/diagnóstico por imagen , Síndrome de Sjögren/diagnóstico por imagen , Resultado del TratamientoRESUMEN
BACKGROUND: There are no prospective, prognostic data comparing cardiovascular magnetic resonance (CMR) and single-photon emission computed tomography (SPECT) in the same population of patients with suspected coronary heart disease (CHD). OBJECTIVE: To establish the ability of CMR and SPECT to predict major adverse cardiovascular events (MACEs). DESIGN: Annual follow-up of the CE-MARC (Clinical Evaluation of MAgnetic Resonance imaging in Coronary heart disease) study for a minimum of 5 years for MACEs (cardiovascular death, acute coronary syndrome, unscheduled revascularization or hospital admission for cardiovascular cause). (Current Controlled Trials registration: ISRCTN77246133). SETTING: Secondary and tertiary care cardiology services. PARTICIPANTS: 752 patients from the CE-MARC study who were being investigated for suspected CHD. MEASUREMENTS: Prediction of time to MACE was assessed by using univariable (log-rank test) and multivariable (Cox proportional hazards regression) analysis. RESULTS: 744 (99%) of the 752 recruited patients had complete follow-up. Of 628 who underwent CMR, SPECT, and the reference standard test of X-ray angiography, 104 (16.6%) had at least 1 MACE. Abnormal findings on CMR (hazard ratio, 2.77 [95% CI, 1.85 to 4.16]; P < 0.001) and SPECT (hazard ratio, 1.62 [CI, 1.11 to 2.38; P = 0.014) were both strong and independent predictors of MACE. Only CMR remained a significant predictor after adjustment for other cardiovascular risk factors, angiography result, or stratification for initial patient treatment. LIMITATION: Data are from a single-center observational study (albeit conducted in a high-volume institution for both CMR and SPECT). CONCLUSION: Five-year follow-up of the CE-MARC study indicates that compared with SPECT, CMR is a stronger predictor of risk for MACEs, independent of cardiovascular risk factors, angiography result, or initial patient treatment. This further supports the role of CMR as an alternative to SPECT for the diagnosis and management of patients with suspected CHD. PRIMARY FUNDING SOURCE: British Heart Foundation.
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PURPOSE: To examine factors associated with false-negative cardiovascular magnetic resonance (MR) perfusion studies within the large prospective Clinical Evaluation of MR imaging in Coronary artery disease (CE-MARC) study population. Myocardial perfusion MR has excellent diagnostic accuracy to detect coronary heart disease (CHD). However, causes of false-negative MR perfusion studies are not well understood. MATERIALS AND METHODS: CE-MARC prospectively recruited patients with suspected CHD and mandated MR, myocardial perfusion scintigraphy, and invasive angiography. This subanalysis identified all patients with significant coronary stenosis by quantitative coronary angiography (QCA) and MR perfusion (1.5T, T1 -weighted gradient echo), using the original blinded image read. We explored patient and imaging characteristics related to false-negative or true-positive MR perfusion results, with reference to QCA. Multivariate regression analysis assessed the likelihood of false-negative MR perfusion according to four characteristics: poor image quality, triple-vessel disease, inadequate hemodynamic response to adenosine, and Duke jeopardy score (angiographic myocardium-at-risk score). RESULTS: In all, 265 (39%) patients had significant angiographic disease (mean age 62, 79% male). Thirty-five (5%) had false-negative and 230 (34%) true-positive MR perfusion. Poor MR perfusion image quality, triple-vessel disease, and inadequate hemodynamic response were similar between false-negative and true-positive groups (odds ratio, OR [95% confidence interval, CI]: 4.1 (0.82-21.0), P = 0.09; 1.2 (0.20-7.1), P = 0.85, and 1.6 (0.65-3.8), P = 0.31, respectively). Mean Duke jeopardy score was significantly lower in the false-negative group (2.6 ± 1.7 vs. 5.4 ± 3.0, OR 0.34 (0.21-0.53), P < 0.0001). CONCLUSION: False-negative cardiovascular MR perfusion studies are uncommon, and more common in patients with lower angiographic myocardium-at-risk. In CE-MARC, poor image quality, triple-vessel disease, and inadequate hemodynamic response were not significantly associated with false-negative MR perfusion.
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Sistema Cardiovascular/fisiopatología , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Imagen por Resonancia Magnética , Anciano , Angiografía , Sistema Cardiovascular/diagnóstico por imagen , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/fisiopatología , Reacciones Falso Negativas , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Perfusión , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores de RiesgoRESUMEN
IMPORTANCE: Among patients with suspected coronary heart disease (CHD), rates of invasive angiography are considered too high. OBJECTIVE: To test the hypothesis that among patients with suspected CHD, cardiovascular magnetic resonance (CMR)-guided care is superior to National Institute for Health and Care Excellence (NICE) guidelines-directed care and myocardial perfusion scintigraphy (MPS)-guided care in reducing unnecessary angiography. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, 3-parallel group, randomized clinical trial using a pragmatic comparative effectiveness design. From 6 UK hospitals, 1202 symptomatic patients with suspected CHD and a CHD pretest likelihood of 10% to 90% were recruited. First randomization was November 23, 2012; last 12-month follow-up was March 12, 2016. INTERVENTIONS: Patients were randomly assigned (240:481:481) to management according to UK NICE guidelines or to guided care based on the results of CMR or MPS testing. MAIN OUTCOMES AND MEASURES: The primary end point was protocol-defined unnecessary coronary angiography (normal fractional flow reserve >0.8 or quantitative coronary angiography [QCA] showing no percentage diameter stenosis ≥70% in 1 view or ≥50% in 2 orthogonal views in all coronary vessels ≥2.5 mm diameter) within 12 months. Secondary end points included positive angiography, major adverse cardiovascular events (MACEs), and procedural complications. RESULTS: Among 1202 symptomatic patients (mean age, 56.3 years [SD, 9.0]; women, 564 [46.9%] ; mean CHD pretest likelihood, 49.5% [SD, 23.8%]), number of patients with invasive coronary angiography after 12 months was 102 in the NICE guidelines group (42.5% [95% CI, 36.2%-49.0%])], 85 in the CMR group (17.7% [95% CI, 14.4%-21.4%]); and 78 in the MPS group (16.2% [95% CI, 13.0%-19.8%]). Study-defined unnecessary angiography occurred in 69 (28.8%) in the NICE guidelines group, 36 (7.5%) in the CMR group, and 34 (7.1%) in the MPS group; adjusted odds ratio of unnecessary angiography: CMR group vs NICE guidelines group, 0.21 (95% CI, 0.12-0.34, P < .001); CMR group vs the MPS group, 1.27 (95% CI, 0.79-2.03, P = .32). Positive angiography proportions were 12.1% (95% CI, 8.2%-16.9%; 29/240 patients) for the NICE guidelines group, 9.8% (95% CI, 7.3%-12.8%; 47/481 patients) for the CMR group, and 8.7% (95% CI, 6.4%-11.6%; 42/481 patients) for the MPS group. A MACE was reported at a minimum of 12 months in 1.7% of patients in the NICE guidelines group, 2.5% in the CMR group, and 2.5% in the MPS group (adjusted hazard ratios: CMR group vs NICE guidelines group, 1.37 [95% CI, 0.52-3.57]; CMR group vs MPS group, 0.95 [95% CI, 0.46-1.95]). CONCLUSIONS AND RELEVANCE: In patients with suspected angina, investigation by CMR resulted in a lower probability of unnecessary angiography within 12 months than NICE guideline-directed care, with no statistically significant difference between CMR and MPS strategies. There were no statistically significant differences in MACE rates. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT01664858.
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Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Imagen de Perfusión Miocárdica , Procedimientos Innecesarios/estadística & datos numéricos , Anciano , Angina de Pecho/diagnóstico por imagen , Angina de Pecho/etiología , Angiografía Coronaria/efectos adversos , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen de Perfusión Miocárdica/efectos adversos , Atención al Paciente/normas , Guías de Práctica Clínica como AsuntoRESUMEN
BACKGROUND: Coronary artery disease is the leading cause of death in women, and underdiagnosis contributes to the high mortality. This study compared the sex-specific diagnostic performance of cardiovascular magnetic resonance (CMR) and single-photon emission computed tomography (SPECT). METHODS AND RESULTS: A total of 235 women and 393 men with suspected angina underwent CMR, SPECT, and x-ray angiography as part of the Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease (CE-MARC) study. CMR comprised adenosine stress/rest perfusion, cine imaging, late gadolinium enhancement, and magnetic resonance coronary angiography. Gated adenosine stress/rest SPECT was performed with (99m)Tc-tetrofosmin. For CMR, the sensitivity in women and men was similar (88.7% versus 85.6%; P=0.57), as was the specificity (83.5% versus 82.8%; P=0.86). For SPECT, the sensitivity was significantly worse in women than in men (50.9% versus 70.8%; P=0.007), but the specificities were similar (84.1% versus 81.3%; P=0.48). The sensitivity in both the female and male groups was significantly higher with CMR than SPECT (P<0.0001 for both), but the specificity was similar (P=0.77 and P=1.00, respectively). For perfusion-only components, CMR outperformed SPECT in women (area under the curve, 0.90 versus 0.67; P<0.0001) and in men (area under the curve, 0.89 versus 0.74; P<0.0001). Diagnostic accuracy was similar in both sexes with perfusion CMR (P=1.00) but was significantly worse in women with SPECT (P<0.0001). CONCLUSIONS: In both sexes, CMR has greater sensitivity than SPECT. Unlike SPECT, there are no significant sex differences in the diagnostic performance of CMR. These findings, plus an absence of ionizing radiation exposure, mean that CMR should be more widely adopted in women with suspected coronary artery disease. CLINICAL TRIAL REGISTRATION URL: http://www.controlled-trials.com. Unique identifier: ISRCTN77246133.
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Enfermedad de la Arteria Coronaria/diagnóstico , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Anciano , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Femenino , Gadolinio , Ventrículos Cardíacos/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Sensibilidad y Especificidad , Factores SexualesRESUMEN
BACKGROUND: A number of investigative strategies exist for the diagnosis of coronary heart disease (CHD). Despite the widespread availability of noninvasive imaging, invasive angiography is commonly used early in the diagnostic pathway. Consequently, approximately 60% of angiograms reveal no evidence of obstructive coronary disease. Reducing unnecessary angiography has potential financial savings and avoids exposing the patient to unnecessary risk. There are no large-scale comparative effectiveness trials of the different diagnostic strategies recommended in international guidelines and none that have evaluated the safety and efficacy of cardiovascular magnetic resonance. TRIAL DESIGN: CE-MARC 2 is a prospective, multicenter, 3-arm parallel group, randomized controlled trial of patients with suspected CHD (pretest likelihood 10%-90%) requiring further investigation. A total of 1,200 patients will be randomized on a 2:2:1 basis to receive 3.0-T cardiovascular magnetic resonance-guided care, single-photon emission computed tomography-guided care (according to American College of Cardiology/American Heart Association appropriate-use criteria), or National Institute for Health and Care Excellence guidelines-based management. The primary (efficacy) end point is the occurrence of unnecessary angiography as defined by a normal (>0.8) invasive fractional flow reserve. Safety of each strategy will be assessed by 3-year major adverse cardiovascular event rates. Cost-effectiveness and health-related quality-of-life measures will be performed. CONCLUSIONS: The CE-MARC 2 trial will provide comparative efficacy and safety evidence for 3 different strategies of investigating patients with suspected CHD, with the intension of reducing unnecessary invasive angiography rates. Evaluation of these management strategies has the potential to improve patient care, health-related quality of life, and the cost-effectiveness of CHD investigation.
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Enfermedad Coronaria/diagnóstico , Imagen por Resonancia Cinemagnética/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Tomografía Computarizada de Emisión de Fotón Único , Angiografía Coronaria/estadística & datos numéricos , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/economía , Análisis Costo-Beneficio , Humanos , Imagen por Resonancia Cinemagnética/economía , Calidad de Vida , Proyectos de Investigación , Medición de Riesgo , Procedimientos Innecesarios/estadística & datos numéricosRESUMEN
BACKGROUND: The CE-MARC study assessed the diagnostic performance investigated the use of cardiovascular magnetic resonance (CMR) in patients with suspected coronary artery disease (CAD). The study used a multi-parametric CMR protocol assessing 4 components: i) left ventricular function; ii) myocardial perfusion; iii) viability (late gadolinium enhancement (LGE)) and iv) coronary magnetic resonance angiography (MRA). In this pre-specified CE-MARC sub-study we assessed the diagnostic accuracy of the individual CMR components and their combinations. METHODS: All patients from the CE-MARC population (n = 752) were included using data from the original blinded-read. The four individual core components of the CMR protocol was determined separately and then in paired and triplet combinations. Results were then compared to the full multi-parametric protocol. RESULTS: CMR and X-ray angiography results were available in 676 patients. The maximum sensitivity for the detection of significant CAD by CMR was achieved when all four components were used (86.5%). Specificity of perfusion (91.8%), function (93.7%) and LGE (95.8%) on its own was significantly better than specificity of the multi-parametric protocol (83.4%) (all P < 0.0001) but with the penalty of decreased sensitivity (86.5% vs. 76.9%, 47.4% and 40.8% respectively). The full multi-parametric protocol was the optimum to rule-out significant CAD (Likelihood Ratio negative (LR-) 0.16) and the LGE component alone was the best to rue-in CAD (LR+ 9.81). Overall diagnostic accuracy was similar with the full multi-parametric protocol (85.9%) compared to paired and triplet combinations. The use of coronary MRA within the full multi-parametric protocol had no additional diagnostic benefit compared to the perfusion/function/LGE combination (overall accuracy 84.6% vs. 84.2% (P = 0.5316); LR- 0.16 vs. 0.21; LR+ 5.21 vs. 5.77). CONCLUSIONS: From this pre-specified sub-analysis of the CE-MARC study, the full multi-parametric protocol had the highest sensitivity and was the optimal approach to rule-out significant CAD. The LGE component alone was the optimal rule-in strategy. Finally the inclusion of coronary MRA provided no additional benefit when compared to the combination of perfusion/function/LGE. TRIAL REGISTRATION: Current Controlled Trials ISRCTN77246133.
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Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Circulación Coronaria , Vasos Coronarios/patología , Vasos Coronarios/fisiopatología , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Cinemagnética/métodos , Imagen de Perfusión Miocárdica/métodos , Anciano , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Reproducibilidad de los Resultados , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Rheumatoid Arthritis (RA) is one of the most common autoimmune diseases, affecting approximately 1% of the UK adult population. Patients suffer considerable pain, stiffness and swelling and can sustain various degrees of joint destruction, deformity, and significant functional decline. In addition, the economic burden due to hospitalisation and loss of employment is considerable, with over 50% of patients being work-disabled within 10 years of diagnosis. Despite several biologic disease modifying anti-rheumatic drugs (bDMARD) now available, there is a lack of data to guide biologic sequencing. In the UK, second-line biologic treatment is restricted to a single option, rituximab. The aim of the SWITCH trial is to establish whether an alternative-mechanism-TNF-inhibitor (TNFi) or abatacept are as effective as rituximab in patients with RA who have failed an initial TNFi drug. METHODS/DESIGN: SWITCH is a pragmatic, phase IV, multi-centre, parallel-group design, open-label, randomised, controlled trial (RCT) comparing alternative-mechanism-TNFi and abatacept with rituximab in patients with RA who have failed an initial TNFi drug. Participants are randomised in a 1:1:1 ratio to receive alternative mechanism TNFi, (monoclonal antibodies: infliximab, adalimumab, certolizumab or golimumab or the receptor fusion protein, etanercept), abatacept or rituximab during the interventional phase (from randomisation up to week 48). Participants are subsequently followed up to a maximum of 96 weeks, which constitutes the observational phase. The primary objective is to establish whether an alternative-mechanism-TNFi or abatacept are non-inferior to rituximab in terms of disease response at 24 weeks post randomisation. The secondary objectives include the comparison of alternative-mechanism-TNFi and abatacept to rituximab in terms of disease response, quality of life, toxicity, safety and structural and bone density outcomes over a 12-month period (48 weeks) and to evaluate the cost-effectiveness of switching patients to alternative active therapies compared to current practice. DISCUSSION: SWITCH is a well-designed trial in this therapeutic area that aims to develop a rational treatment algorithm to potentially inform personalised treatment regimens (as opposed to switching all patients to only one available (and possibly unsuccessful) therapy), which may lead to long-term improved patient outcomes and gains in population health. TRIAL REGISTRATION: UKCRN Portfolio ID: 12343; ISRCTN89222125 ; NCT01295151.
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Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Inmunoconjugados/uso terapéutico , Abatacept , Antirreumáticos/farmacología , Humanos , Inmunoconjugados/farmacología , Proyectos de Investigación , Rituximab , Insuficiencia del Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidoresRESUMEN
BACKGROUND: Primary Sjögren's Syndrome (PSS) mainly affects women (9:1 female:male ratio) and is one of the commonest autoimmune diseases with a prevalence of 0.1 - 0.6% of adult women. For patients with PSS there is currently no effective therapy that can alter the progression of the disease. The aim of the TRACTISS study is to establish whether in patients with PSS, treatment with rituximab improves clinical outcomes. METHODS/DESIGN: TRACTISS is a UK multi-centre, double-blind, randomised, controlled, parallel group trial of 110 patients with PSS. Patients will be randomised on a 1:1 basis to receive two courses of either rituximab or placebo infusion in addition to standard therapy, and will be followed up for up to 48 weeks. The primary objective is to assess the extent to which rituximab improves symptoms of fatigue and oral dryness. Secondary outcomes include ocular dryness, salivary flow rates, lacrimal flow, patient quality of life, measures of disease damage and disease activity, serological and peripheral blood biomarkers, and glandular histology and composition. DISCUSSION: The TRACTISS trial will provide direct evidence as to whether rituximab in patients with PSS leads to an improvement in patient symptoms and a reduction in disease damage and activity. TRIAL REGISTRATION: UKCRN Portfolio ID: 9809 ISRCTN65360827.
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Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Linfocitos B/efectos de los fármacos , Factores Inmunológicos/administración & dosificación , Proyectos de Investigación , Síndrome de Sjögren/tratamiento farmacológico , Anticuerpos Monoclonales de Origen Murino/efectos adversos , Linfocitos B/inmunología , Biomarcadores/sangre , Protocolos Clínicos , Progresión de la Enfermedad , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Factores Inmunológicos/efectos adversos , Infusiones Intravenosas , Masculino , Calidad de Vida , Rituximab , Salivación/efectos de los fármacos , Síndrome de Sjögren/sangre , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/inmunología , Síndrome de Sjögren/fisiopatología , Lágrimas/metabolismo , Factores de Tiempo , Resultado del Tratamiento , Reino UnidoRESUMEN
BACKGROUND: In patients with suspected coronary heart disease, single-photon emission computed tomography (SPECT) is the most widely used test for the assessment of myocardial ischaemia, but its diagnostic accuracy is reported to be variable and it exposes patients to ionising radiation. The aim of this study was to establish the diagnostic accuracy of a multiparametric cardiovascular magnetic resonance (CMR) protocol with x-ray coronary angiography as the reference standard, and to compare CMR with SPECT, in patients with suspected coronary heart disease. METHODS: In this prospective trial patients with suspected angina pectoris and at least one cardiovascular risk factor were scheduled for CMR, SPECT, and invasive x-ray coronary angiography. CMR consisted of rest and adenosine stress perfusion, cine imaging, late gadolinium enhancement, and MR coronary angiography. Gated adenosine stress and rest SPECT used (99m)Tc tetrofosmin. The primary outcome was diagnostic accuracy of CMR. This trial is registered at controlled-trials.com, number ISRCTN77246133. FINDINGS: In the 752 recruited patients, 39% had significant CHD as identified by x-ray angiography. For multiparametric CMR the sensitivity was 86·5% (95% CI 81·8-90·1), specificity 83·4% (79·5-86·7), positive predictive value 77·2%, (72·1-81·6) and negative predictive value 90·5% (87·1-93·0). The sensitivity of SPECT was 66·5% (95% CI 60·4-72·1), specificity 82·6% (78·5-86·1), positive predictive value 71·4% (65·3-76·9), and negative predictive value 79·1% (74·8-82·8). The sensitivity and negative predictive value of CMR and SPECT differed significantly (p<0·0001 for both) but specificity and positive predictive value did not (p=0·916 and p=0·061, respectively). INTERPRETATION: CE-MARC is the largest, prospective, real world evaluation of CMR and has established CMR's high diagnostic accuracy in coronary heart disease and CMR's superiority over SPECT. It should be adopted more widely than at present for the investigation of coronary heart disease. FUNDING: British Heart Foundation.
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Enfermedad Coronaria/diagnóstico , Angiografía por Resonancia Magnética , Imagen de Perfusión Miocárdica , Tomografía Computarizada de Emisión de Fotón Único , Adenosina , Medios de Contraste , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Gadolinio DTPA , Humanos , Valor Predictivo de las Pruebas , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To analyze the impact of modern glucose-monitoring strategies on glycemic and patient-related outcomes in individuals with type 2 diabetes (T2D) and recent myocardial infarction (MI) and assess cost effectiveness. RESEARCH DESIGN AND METHODS: LIBERATES was a multicenter two-arm randomized trial comparing self-monitoring of blood glucose (SMBG) with intermittently scanned continuous glucose monitoring (isCGM), also known as flash CGM, in individuals with T2D and recent MI, treated with insulin and/or a sulphonylurea before hospital admission. The primary outcome measure was time in range (TIR) (glucose 3.9-10 mmol/L/day) on days 76-90 post-randomization. Secondary and exploratory outcomes included time in hypoglycemia, hemoglobin A1c (HbA1c), clinical outcome, quality of life (QOL), and cost effectiveness. RESULTS: Of 141 participants randomly assigned (median age 63 years; interquartile range 53, 70), 73% of whom were men, isCGM was associated with increased TIR by 17 min/day (95% credible interval -105 to +153 min/day), with 59% probability of benefit. Users of isCGM showed lower hypoglycemic exposure (<3.9 mmol/L) at days 76-90 (-80 min/day; 95% CI -118, -43), also evident at days 16-30 (-28 min/day; 95% CI -92, 2). Compared with baseline, HbA1c showed similar reductions of 7 mmol/mol at 3 months in both study arms. Combined glycemic emergencies and mortality occurred in four isCGM and seven SMBG study participants. QOL measures marginally favored isCGM, and the intervention proved to be cost effective. CONCLUSIONS: Compared with SMBG, isCGM in T2D individuals with MI marginally increases TIR and significantly reduces hypoglycemic exposure while equally improving HbA1c, explaining its cost effectiveness. Studies are required to understand whether these glycemic differences translate into longer-term clinical benefit.
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Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Masculino , Humanos , Persona de Mediana Edad , Femenino , Glucemia , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada , Calidad de Vida , Automonitorización de la Glucosa Sanguínea/métodos , Hipoglucemiantes/uso terapéuticoRESUMEN
AIMS: Guidelines for suspected cardiac chest pain have used historical risk stratification tools, advocating invasive coronary angiography (ICA) first-line in those at highest risk. We aimed to determine whether different strategies to manage suspected stable angina affected medium-term cardiovascular event rates and patient-reported quality of life (QoL) measures. METHODS: CE-MARC 2, a three-arm parallel group trial, randomised patients with suspected stable cardiac chest pain and a Duke Clinical pretest likelihood of coronary artery disease between 10% and 90%. Patients were randomised to either first-line cardiovascular magnetic resonance (CMR), single-photon emission computed tomography (SPECT) or the UK National Institute for Health and Care Excellence (NICE) CG95 (2010) guidelines-directed care. For the three arms, 1-year and 3-year first major adverse cardiovascular event (MACE) rates and QoL assessed by the Seattle Angina Questionnaire, Short Form 12 (V.12) Questionnaire and EuroQol-5 Dimension Questionnaire were recorded. RESULTS: 1202 patients were randomised to CMR (n=481), SPECT (n=481) and NICE (n=240). Forty-two patients (18 CMR, 18 SPECT, 6 NICE) experienced one or more MACEs. The percentage rates (95% CIs) of MACE in the CMR, SPECT and NICE groups at 3 years were 3.7% (2.4%, 5.8%), 3.7% (2.4%, 5.8%) and 2.1% (0.9%, 4.8%), respectively. QoL scores did not significantly differ across domains. CONCLUSION: Despite a fourfold increase in referrals for ICA, the NICE CG95 (2010) guidelines risk-stratified care strategy did not significantly reduce 3-year MACE or improve QoL, as compared with functional imaging with CMR or SPECT. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT01664858).
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Angina Estable , Enfermedad de la Arteria Coronaria , Humanos , Calidad de Vida , Angiografía Coronaria/métodos , Dolor en el Pecho , Angina Estable/diagnóstico por imagen , Angina Estable/terapiaRESUMEN
OBJECTIVE: This study aimed to identify peripheral and salivary gland (SG) biomarkers of response/resistance to B cell depletion based on the novel concise Composite of Relevant Endpoints for Sjögren Syndrome (cCRESS) and candidate Sjögren Tool for Assessing Response (STAR) composite endpoints. METHODS: Longitudinal analysis of peripheral blood and SG biopsies was performed pre- and post-treatment from the Trial of Anti-B Cell Therapy in Patients With Primary Sjögren Syndrome (TRACTISS) combining flow cytometry immunophenotyping, serum cytokines, and SG bulk RNA sequencing. RESULTS: Rituximab treatment prevented the worsening of SG inflammation observed in the placebo arm, by inhibiting the accumulation of class-switched memory B cells within the SG. Furthermore, rituximab significantly down-regulated genes involved in immune-cell recruitment, lymphoid organization alongside antigen presentation, and T cell co-stimulatory pathways. In the peripheral compartment, rituximab down-regulated immunoglobulins and auto-antibodies together with pro-inflammatory cytokines and chemokines. Interestingly, patients classified as responders according to STAR displayed significantly higher baseline levels of C-X-C motif chemokine ligand-13 (CXCL13), interleukin (IL)-22, IL-17A, IL-17F, and tumor necrosis factor-α (TNF-α), whereas a longitudinal analysis of serum T cell-related cytokines showed a selective reduction in both STAR and cCRESS responder patients. Conversely, cCRESS response was better associated with biomarkers of SG immunopathology, with cCRESS-responders showing a significant decrease in SG B cell infiltration and reduced expression of transcriptional gene modules related to T cell costimulation, complement activation, and Fcγ-receptor engagement. Finally, cCRESS and STAR response were associated with a significant improvement in SG exocrine function linked to transcriptional evidence of SG epithelial and metabolic restoration. CONCLUSION: Rituximab modulates both peripheral and SG inflammation, preventing the deterioration of exocrine function with functional and metabolic restoration of the glandular epithelium. Response assessed by newly developed cCRESS and STAR criteria was associated with differential modulation of peripheral and SG biomarkers, emerging as novel tools for patient stratification.
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Background: Exercise is advised for young adults with elevated blood pressure, but no trials have investigated efficacy at this age. We aimed to determine whether aerobic exercise, self-monitoring and motivational coaching lowers blood pressure in this group. Methods: The study was a single-centre, open, two-arm, parallel superiority randomized clinical trial with open community-based recruitment of physically-inactive 18-35 year old adults with awake 24 h blood pressure 115/75mmHg-159/99 mmHg and BMI<35 kg/m2. The study took place in the Cardiovascular Clinical Research Facility, John Radcliffe Hospital, Oxford, UK. Participants were randomized (1:1) with minimisation factors sex, age (<24, 24-29, 30-35 years) and gestational age at birth (<32, 32-37, >37 weeks) to the intervention group, who received 16-weeks aerobic exercise training (three aerobic training sessions per week of 60 min per session at 60-80% peak heart rate, physical activity self-monitoring with encouragement to do 10,000 steps per day and motivational coaching to maintain physical activity upon completion of the intervention. The control group were sign-posted to educational materials on hypertension and recommended lifestyle behaviours. Investigators performing statistical analyses were blinded to group allocation. The primary outcome was 24 h awake ambulatory blood pressure (systolic and diastolic) change from baseline to 16-weeks on an intention-to-treat basis. Clinicaltrials.gov registered on March 30, 2016 (NCT02723552). Findings: Enrolment occurred between 30/06/2016-26/10/2018. Amongst the 203 randomized young adults (n = 102 in the intervention group; n = 101 in the control group), 178 (88%; n = 76 intervention group, n = 84 control group) completed 16-week follow-up and 160 (79%; n = 68 intervention group, n = 69 control group) completed 52-weeks follow-up. There were no group differences in awake systolic (0·0 mmHg [95%CI, -2·9 to 2·8]; P = 0·98) or awake diastolic ambulatory blood pressure (0·6 mmHg [95%CI, -1·4. to 2·6]; P = 0·58). Aerobic training increased peak oxygen uptake (2·8 ml/kg/min [95%CI, 1·6 to 4·0]) and peak wattage (14·2watts [95%CI, 7·6 to 20·9]) at 16-weeks. There were no intervention effects at 52-weeks follow-up. Intepretation: These results do not support the exclusive use of moderate to high intensity aerobic exercise training for blood pressure control in young adults. Funding: Wellcome Trust, British Heart Foundation, National Institute for Health Research, Oxford Biomedical Research Centre.
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OBJECTIVE: To improve communication of harm in publications of randomised controlled trials via the development of recommendations for visually presenting harm outcomes. DESIGN: Consensus study. SETTING: 15 clinical trials units registered with the UK Clinical Research Collaboration, an academic population health department, Roche Products, and The BMJ. PARTICIPANTS: Experts in clinical trials: 20 academic statisticians, one industry statistician, one academic health economist, one data graphics designer, and two clinicians. MAIN OUTCOME: measures A methodological review of statistical methods identified visualisations along with those recommended by consensus group members. Consensus on visual recommendations was achieved (at least 60% of the available votes) over a series of three meetings with participants. The participants reviewed and critically appraised candidate visualisations against an agreed framework and voted on whether to endorse each visualisation. Scores marginally below this threshold (50-60%) were revisited for further discussions and votes retaken until consensus was reached. RESULTS: 28 visualisations were considered, of which 10 are recommended for researchers to consider in publications of main research findings. The choice of visualisations to present will depend on outcome type (eg, binary, count, time-to-event, or continuous), and the scenario (eg, summarising multiple emerging events or one event of interest). A decision tree is presented to assist trialists in deciding which visualisations to use. Examples are provided of each endorsed visualisation, along with an example interpretation, potential limitations, and signposting to code for implementation across a range of standard statistical software. Clinician feedback was incorporated into the explanatory information provided in the recommendations to aid understanding and interpretation. CONCLUSIONS: Visualisations provide a powerful tool to communicate harms in clinical trials, offering an alternative perspective to the traditional frequency tables. Increasing the use of visualisations for harm outcomes in clinical trial manuscripts and reports will provide clearer presentation of information and enable more informative interpretations. The limitations of each visualisation are discussed and examples of where their use would be inappropriate are given. Although the decision tree aids the choice of visualisation, the statistician and clinical trial team must ultimately decide the most appropriate visualisations for their data and objectives. Trialists should continue to examine crude numbers alongside visualisations to fully understand harm profiles.
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OBJECTIVE: To assess the cost-effectiveness of management strategies for patients presenting with chest pain and suspected coronary heart disease (CHD): (1) cardiovascular magnetic resonance (CMR); (2) myocardial perfusion scintigraphy (MPS); and (3) UK National Institute for Health and Care Excellence (NICE) guideline-guided care. METHODS: Using UK data for 1202 patients from the Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease 2 trial, we conducted an economic evaluation to assess the cost-effectiveness of CMR, MPS and NICE guidelines. Health outcomes were expressed as quality-adjusted life-years (QALYs), and costs reflected UK pound sterling in 2016-2017. Cost-effectiveness results were presented as incremental cost-effectiveness ratios and incremental net health benefits overall and for low, medium and high pretest likelihood of CHD subgroups. RESULTS: CMR had the highest estimated QALY gain overall (2.21 (95% credible interval 2.15, 2.26) compared with 2.07 (1.92, 2.20) for NICE and 2.11 (2.01, 2.22) for MPS) and incurred comparable costs (overall £1625 (£1431, £1824) compared with £1753 (£1473, £2032) for NICE and £1768 (£1572, £1989) for MPS). Overall, CMR was the cost-effective strategy, being the dominant strategy (more effective, less costly) with incremental net health benefits per patient of 0.146 QALYs (-0.18, 0.406) compared with NICE guidelines at a cost-effectiveness threshold of £15 000 per QALY (93% probability of cost-effectiveness). Results were similar in the pretest likelihood subgroups. CONCLUSIONS: CMR-guided care is cost-effective overall and across all pretest likelihood subgroups, compared with MPS and NICE guidelines.
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Enfermedad Coronaria/diagnóstico por imagen , Imagen por Resonancia Cinemagnética/economía , Imagen de Perfusión Miocárdica/economía , Análisis Costo-Beneficio , Femenino , Humanos , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Años de Vida Ajustados por Calidad de Vida , Reino UnidoRESUMEN
Hyperglycaemia in individuals with type 2 diabetes (T2D) and myocardial infarction (MI) is associated with guarded clinical prognosis. Studies improving glucose levels in T2D following MI relied on HbA1c as the main glycaemic marker, failing to address potential adverse effects of hypoglycaemia and glucose variability. We describe the design of the LIBERATES trial that investigates the role of flash glucose monitoring in optimising glycaemic markers in high vascular risk individuals with T2D. This multicentre trial is designed to recruit up to 150 insulin and/or sulphonylurea-treated T2D patients, within 5 days of a proven MI. Individuals will be randomised 1:1 into intervention and control groups using flash glucose monitoring sensors and traditional self-monitoring of blood glucose, respectively. The control group will also wear a blinded continuous glucose monitoring sensor. The primary outcome is the difference in time spent in euglycaemia (defined as glucose levels between 3.9-10.0 mmol/l), comparing study groups 3 months following recruitment, assessed daily for 14 days and as an average. Secondary and exploratory end points include time spent in hypoglycaemia and hyperglycaemia, HbA1c, quality of life measures, major adverse cardiac events and cost-effectiveness of the intervention. This study will establish the role of flash glucose monitoring in glycaemic management of individuals with T2D sustaining a cardiac event.(Trial Registration: ISRCTN14974233, registered 12th June 2017).