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1.
Health Technol Assess ; 28(18): 1-55, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38551218

RESUMO

Background: Allopurinol is a xanthine oxidase inhibitor that lowers serum uric acid and is used to prevent acute gout flares in patients with gout. Observational and small interventional studies have suggested beneficial cardiovascular effects of allopurinol. Objective: To determine whether allopurinol improves major cardiovascular outcomes in patients with ischaemic heart disease. Design: Prospective, randomised, open-label, blinded endpoint multicentre clinical trial. Setting: Four hundred and twenty-four UK primary care practices. Participants: Aged 60 years and over with ischaemic heart disease but no gout. Interventions: Participants were randomised (1 : 1) using a central web-based randomisation system to receive allopurinol up to 600 mg daily that was added to usual care or to continue usual care. Main outcome measures: The primary outcome was the composite of non-fatal myocardial infarction, non-fatal stroke or cardiovascular death. Secondary outcomes were non-fatal myocardial infarction, non-fatal stroke, cardiovascular death, all-cause mortality, hospitalisation for heart failure, hospitalisation for acute coronary syndrome, coronary revascularisation, hospitalisation for acute coronary syndrome or coronary revascularisation, all cardiovascular hospitalisations, quality of life and cost-effectiveness. The hazard ratio (allopurinol vs. usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis. Results: From 7 February 2014 to 2 October 2017, 5937 participants were enrolled and randomised to the allopurinol arm (n = 2979) or the usual care arm (n = 2958). A total of 5721 randomised participants (2853 allopurinol; 2868 usual care) were included in the modified intention-to-treat analysis population (mean age 72.0 years; 75.5% male). There was no difference between the allopurinol and usual care arms in the primary endpoint, 314 (11.0%) participants in the allopurinol arm (2.47 events per 100 patient-years) and 325 (11.3%) in the usual care arm (2.37 events per 100 patient-years), hazard ratio 1.04 (95% confidence interval 0.89 to 1.21); p = 0.65. Two hundred and eighty-eight (10.1%) participants in the allopurinol arm and 303 (10.6%) participants in the usual care arm died, hazard ratio 1.02 (95% confidence interval 0.87 to 1.20); p = 0.77. The pre-specified health economic analysis plan was to perform a 'within trial' cost-utility analysis if there was no statistically significant difference in the primary endpoint, so NHS costs and quality-adjusted life-years were estimated over a 5-year period. The difference in costs between treatment arms was +£115 higher for allopurinol (95% confidence interval £17 to £210) with no difference in quality-adjusted life-years (95% confidence interval -0.061 to +0.060). We conclude that there is no evidence that allopurinol used in line with the study protocol is cost-effective. Limitations: The results may not be generalisable to younger populations, other ethnic groups or patients with more acute ischaemic heart disease. One thousand six hundred and thirty-seven participants (57.4%) in the allopurinol arm withdrew from randomised treatment, but an on-treatment analysis gave similar results to the main analysis. Conclusions: The ALL-HEART study showed that treatment with allopurinol 600 mg daily did not improve cardiovascular outcomes compared to usual care in patients with ischaemic heart disease. We conclude that allopurinol should not be recommended for the secondary prevention of cardiovascular events in patients with ischaemic heart disease but no gout. Future work: The effects of allopurinol on cardiovascular outcomes in patients with ischaemic heart disease and co-existing hyperuricaemia or clinical gout could be explored in future studies. Trial registration: This trial is registered as EU Clinical Trials Register (EudraCT 2013-003559-39) and ISRCTN (ISRCTN 32017426). Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 11/36/41) and is published in full in Health Technology Assessment; Vol. 28, No. 18. See the NIHR Funding and Awards website for further award information.


The purpose of the ALL-HEART study was to determine whether giving allopurinol to people with ischaemic heart disease (also commonly known as coronary heart disease) would reduce their risk of having a heart attack, stroke or of dying from cardiovascular disease. Allopurinol is a medication usually given to patients with gout to prevent acute gout flares. It is not currently used to treat ischaemic heart disease. We randomly allocated people aged over 60 years with ischaemic heart disease to take up to 600 mg of allopurinol daily (in addition to their usual care) or to continue with their usual care. We then monitored participants for several years and recorded any major health events such as heart attacks, strokes and deaths. We obtained most of the follow-up data from centrally held electronic hospital admissions and death records, making the study easier for participants and more cost-efficient. We asked participants in both groups to complete questionnaires to assess their quality of life during the study. We also collected data to determine whether there was any economic benefit to the NHS of using allopurinol in patients with ischaemic heart disease. There was no difference in the risk of heart attacks, strokes or death from cardiovascular disease between the participants given allopurinol and those in the group continuing their usual care. We also found no difference in the risks of other cardiovascular events, deaths from any cause or quality-of-life measurements between the allopurinol and usual care groups. The results of the ALL-HEART study suggest that we should not recommend that allopurinol be given to people with ischaemic heart disease to prevent further cardiovascular events or deaths.


Assuntos
Síndrome Coronariana Aguda , Gota , Infarto do Miocárdio , Isquemia Miocárdica , Acidente Vascular Cerebral , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Alopurinol/uso terapêutico , Análise Custo-Benefício , Qualidade de Vida , Estudos Prospectivos , Ácido Úrico , Isquemia Miocárdica/tratamento farmacológico , Gota/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico
2.
Lancet ; 400(10359): 1195-1205, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36216006

RESUMO

BACKGROUND: Allopurinol is a urate-lowering therapy used to treat patients with gout. Previous studies have shown that allopurinol has positive effects on several cardiovascular parameters. The ALL-HEART study aimed to determine whether allopurinol therapy improves major cardiovascular outcomes in patients with ischaemic heart disease. METHODS: ALL-HEART was a multicentre, prospective, randomised, open-label, blinded-endpoint trial done in 18 regional centres in England and Scotland, with patients recruited from 424 primary care practices. Eligible patients were aged 60 years or older, with ischaemic heart disease but no history of gout. Participants were randomly assigned (1:1), using a central web-based randomisation system accessed via a web-based application or an interactive voice response system, to receive oral allopurinol up-titrated to a dose of 600 mg daily (300 mg daily in participants with moderate renal impairment at baseline) or to continue usual care. The primary outcome was the composite cardiovascular endpoint of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death. The hazard ratio (allopurinol vs usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis (excluding randomly assigned patients later found to have met one of the exclusion criteria). The safety analysis population included all patients in the modified intention-to-treat usual care group and those who took at least one dose of randomised medication in the allopurinol group. This study is registered with the EU Clinical Trials Register, EudraCT 2013-003559-39, and ISRCTN, ISRCTN32017426. FINDINGS: Between Feb 7, 2014, and Oct 2, 2017, 5937 participants were enrolled and then randomly assigned to receive allopurinol or usual care. After exclusion of 216 patients after randomisation, 5721 participants (mean age 72·0 years [SD 6·8], 4321 [75·5%] males, and 5676 [99·2%] white) were included in the modified intention-to-treat population, with 2853 in the allopurinol group and 2868 in the usual care group. Mean follow-up time in the study was 4·8 years (1·5). There was no evidence of a difference between the randomised treatment groups in the rates of the primary endpoint. 314 (11·0%) participants in the allopurinol group (2·47 events per 100 patient-years) and 325 (11·3%) in the usual care group (2·37 events per 100 patient-years) had a primary endpoint (hazard ratio [HR] 1·04 [95% CI 0·89-1·21], p=0·65). 288 (10·1%) participants in the allopurinol group and 303 (10·6%) participants in the usual care group died from any cause (HR 1·02 [95% CI 0·87-1·20], p=0·77). INTERPRETATION: In this large, randomised clinical trial in patients aged 60 years or older with ischaemic heart disease but no history of gout, there was no difference in the primary outcome of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death between participants randomised to allopurinol therapy and those randomised to usual care. FUNDING: UK National Institute for Health and Care Research.


Assuntos
Doença da Artéria Coronariana , Gota , Infarto do Miocárdio , Isquemia Miocárdica , Acidente Vascular Cerebral , Idoso , Alopurinol/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Feminino , Gota/tratamento farmacológico , Humanos , Masculino , Infarto do Miocárdio/tratamento farmacológico , Isquemia Miocárdica/tratamento farmacológico , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento , Reino Unido , Ácido Úrico
3.
BMC Med Imaging ; 16: 18, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-26923316

RESUMO

BACKGROUND: The aim of this study was to use whole body cardiovascular magnetic resonance imaging (WB CVMR) to assess the heart and arterial network in a single examination, so as to describe the burden of atherosclerosis and subclinical disease in participants with symptomatic single site vascular disease. METHODS: 64 patients with a history of symptomatic single site vascular disease (38 coronary artery disease (CAD), 9 cerebrovascular disease, 17 peripheral arterial disease (PAD)) underwent whole body angiogram and cardiac MR in a 3 T scanner. The arterial tree was subdivided into 31 segments and each scored according to the degree of stenosis. From this a standardised atheroma score (SAS) was calculated. Cine and late gadolinium enhancement images of the left ventricle were obtained. RESULTS: Asymptomatic atherosclerotic disease with greater than 50% stenosis in arteries other than that responsible for their presenting complain was detected in 37% of CAD, 33% of cerebrovascular and 47% of PAD patients. Unrecognised myocardial infarcts were observed in 29% of PAD patients. SAS was significantly higher in PAD patients 24 (17.5-30.5) compared to CAD 4 (2-11.25) or cerebrovascular disease patients 6 (2-10) (ANCOVA p < 0.001). Standardised atheroma score positively correlated with age (ß 0.36 p = 0.002), smoking status (ß 0.34 p = 0.002), and LV mass (ß -0.61 p = 0.001) on multiple linear regression. CONCLUSION: WB CVMR is an effective method for the stratification of cardiovascular disease. The high prevalence of asymptomatic arterial disease, and silent myocardial infarctions, particularly in the peripheral arterial disease group, demonstrates the importance of a systematic approach to the assessment of cardiovascular disease.


Assuntos
Aterosclerose/diagnóstico , Doenças Cardiovasculares/complicações , Imageamento por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Fatores Etários , Idoso , Aterosclerose/epidemiologia , Doenças Cardiovasculares/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco
4.
PLoS One ; 8(1): e54100, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23382871

RESUMO

BACKGROUND: Idiopathic congenital talipes equinovarus (CTEV) is the commonest form of clubfoot. Its exact cause is unknown, although it is related to limb development. The aim of this study was to quantify the anatomy of the muscle, subcutaneous fat, tibia, fibula and arteries in the lower legs of teenagers and young adults with CTEV using 3D magnetic resonance imaging (MRI), and thus to investigate the anatomical differences between CTEV participants and controls. METHODOLOGY/PRINCIPAL FINDINGS: The lower legs of six CTEV (2 bilateral, 4 unilateral) and five control young adults (age 12-28) were imaged using a 3T MRI Philips scanner. 5 of the CTEV participants had undergone soft-tissue and capsular release surgery. 3D T1-weighted and 3D magnetic resonance angiography (MRA) images were acquired. Segmentation software was used for volumetric, anatomical and image analysis. Kolmogorov-Smirnov tests were performed. The volumes of the lower affected leg, muscle, tibia and fibula in unilateral CTEV participants were consistently smaller compared to their contralateral unaffected leg, this was most pronounced in muscle. The proportion of muscle in affected CTEV legs was significantly reduced compared with control and unaffected CTEV legs, whilst proportion of muscular fat increased. No spatial abnormalities in the location or branching of arteries were detected, but hypoplastic anomalies were observed. CONCLUSIONS/SIGNIFICANCE: Combining 3D MRI and MRA is effective for quantitatively characterizing CTEV anatomy. Reduction in leg muscle volume appears to be a sensitive marker. Since 5/6 CTEV cases had soft-tissue surgery, further work is required to confirm that the treatment did not affect the MRI features observed. We propose that the proportion of muscle and intra-muscular fat within the lower leg could provide a valuable addition to current clinical CTEV classification. These measures could be useful for clinical care and guiding treatment pathways, as well as treatment research and clinical audit.


Assuntos
Pé Torto Equinovaro/diagnóstico por imagem , Pé Torto Equinovaro/fisiopatologia , Perna (Membro)/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adolescente , Adulto , Criança , Pé Torto Equinovaro/classificação , Feminino , Humanos , Perna (Membro)/fisiopatologia , Masculino , Radiografia , Adulto Jovem
5.
Anticancer Res ; 32(2): 415-20, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22287727

RESUMO

AIM: To assess the efficacy of multiple treatment of phosphatidylinositol-3-kinase (PI3K) inhibitor on autochthonous tumours in phosphatase and tensin homologue (Pten)-deficient genetically engineered mouse cancer models using a longitudinal magnetic resonance imaging (MRI) protocol. MATERIALS AND METHODS: Using 3D MRI, B-cell follicular lymphoma growth was quantified in a Pten(+/-)Lkb1(+/hypo) mouse line, before, during and after repeated treatments with a PI3K inhibitor GDC-0941 (75 mg/kg). RESULTS: Mean pre-treatment linear tumour growth rate was 16.5±12.8 mm(3)/week. Repeated 28-day GDC-0941 administration, with 21 days 'off-treatment', induced average tumour regression of 41±7%. Upon cessation of the second treatment (which was not permanently cytocidal), tumours re-grew with an average linear growth rate of 40.1±15.5 mm(3)/week. There was no evidence of chemoresistance. CONCLUSION: This protocol can accommodate complex dosing schedules, as well as combine different cancer therapies. It reduces biological variability problems and resulted in a 10-fold reduction in mouse numbers compared with terminal assessment methods. It is ideal for preclinical efficacy studies and for phenotyping molecularly characterized mouse models when investigating gene function.


Assuntos
Inibidores Enzimáticos/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Indazóis/farmacologia , Linfoma de Células B/tratamento farmacológico , Linfoma Folicular/tratamento farmacológico , PTEN Fosfo-Hidrolase/deficiência , Inibidores de Fosfoinositídeo-3 Quinase , Sulfonamidas/farmacologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/patologia , Estudos Longitudinais , Linfoma de Células B/enzimologia , Linfoma de Células B/patologia , Linfoma Folicular/enzimologia , Linfoma Folicular/patologia , Imageamento por Ressonância Magnética/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
6.
Nanotechnology ; 22(9): 095706, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21270482

RESUMO

In this study we investigate the potential of multiwall carbon nanotubes (MWCNTs) with low metal impurities (2.57% iron) as magnetic resonance imaging (MRI) contrast agents. Taking into account probable aggregation at high MWCNTs concentration analysis shows that the r(2) relaxivity of MWCNTs in 1% agarose gels at 19 °C is 564 ± 41 s(-1) mM(-1); this is attributed to both the presence of iron oxide impurities and also to the carbon MWCNT structure itself. Stem cells were labelled with MWCNTs to demonstrate the effectiveness of MWCNTs as MRI contrast agents for cellular MRI. The MWCNTs did not impair cell viability or proliferation. These results suggest that the MRI contrast agent properties of the MWCNTs could be used in vivo for stem cell tracking/imaging and during MWCNT-mediated targeted electro-chemotherapy of tumours.


Assuntos
Rastreamento de Células/métodos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Células-Tronco Mesenquimais/citologia , Nanotubos de Carbono/análise , Animais , Células Cultivadas , Meios de Contraste/síntese química , Nanotubos de Carbono/química , Ratos , Ratos Endogâmicos WF
7.
J Am Chem Soc ; 132(42): 15022-9, 2010 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-20919679

RESUMO

Iron-platinum alloy nanoparticles (FePt NPs) are extremely promising candidates for the next generation of contrast agents for magnetic resonance (MR) diagnostic imaging and MR-guided interventions, including hyperthermic ablation of solid cancers. FePt has high Curie temperature, saturation magnetic moment, magneto-crystalline anisotropy, and chemical stability. We describe the synthesis and characterization of a family of biocompatible FePt NPs suitable for biomedical applications, showing and discussing that FePt NPs can exhibit low cytotoxicity. The importance of engineering the interface of strongly magnetic NPs using a coating allowing free aqueous permeation is demonstrated to be an essential parameter in the design of new generations of diagnostic and therapeutic MRI contrast agents. We report effective cell internalization of FePt NPs and demonstrate that they can be used for cellular imaging and in vivo MRI applications. This opens the way for several future applications of FePt NPs, including regenerative medicine and stem cell therapy in addition to enhanced MR diagnostic imaging.


Assuntos
Materiais Biocompatíveis , Nanopartículas , Linhagem Celular , Imageamento por Ressonância Magnética , Microscopia Eletrônica de Transmissão , Difração de Raios X
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