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1.
NPJ Sci Food ; 8(1): 10, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316809

RESUMEN

Many recent very influential reports, including those from the Global Burden of Disease (GBD) Risk Factor Collaborators, the EAT-Lancet Commission on Food, Planet, Health, and the Lancet Countdown on Health and Climate Change, have recommended dramatic reductions or total exclusion of animal-source foods, particularly ruminant products (red meat and dairy), from the human diet. They strongly suggest that these dietary shifts will not only benefit planetary health but also human health. However, as detailed in this perspective, there are grounds for considerable concern in regard to the quality and transparency of the input data, the validity of the assumptions, and the appropriateness of the statistical modelling, used in the calculation of the global health estimates, which underpin the claimed human health benefits. The lessor bioavailability of protein and key micronutrients from plant-source foods versus animal-source foods was not adequately recognised nor addressed in any of these reports. Furthermore, assessments of bias and certainty were either limited or absent. Despite many of these errors and limitations being publically acknowledged by the GBD and the EAT-Lancet authors, no corrections have been applied to the published papers. As a consequence, these reports continue to erroneously influence food policy decisions and international dietary guidelines, such as the World Wildlife Fund's Livewell Diet, and the Nordic Nutrition Recommendations 2023.

2.
BMC Med Educ ; 23(1): 4, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36600232

RESUMEN

BACKGROUND: The COVID-19 pandemic has created unprecedented challenges for medical students and educators worldwide. Groups 1, 2 and 3 of year 3, semester 2 medical students at the Royal College of Surgeons in Ireland (n = 275) had only completed 2, 5 and 7 weeks, respectively, of their scheduled 10-week clinical medicine and surgery attachments, prior to the Irish shutdown of all in-person non-essential activities, including medical student education. METHODS: We developed and delivered an online case-based program, focused on history-taking skills and clinical reasoning, using simulated patients and video technologies. 12 tutorials were delivered over 6 weeks to 35 subgroups of 8 students in line with program learning outcomes. Both simulated patients (n = 36), and tutors (n = 45, from retired clinical professors to newly graduated physicians), were rapidly upskilled in Blackboard Collaborate and Microsoft Teams, and also in the provision of constructive feedback. We evaluated this newly developed program by the following three criteria: student attendance, achieved grades, and student feedback. RESULTS: Attendance at the 12 tutorials was higher amongst group 1 and 2 students (75 and 73%) by comparison with group 3 students (60%) (p = < 0.001). Of the 273 students that sat the Year 3 Semester 2 online long case assessment, 93% were successful. Despite group 1 students having the least prior clinical experience, results were similar to those of groups 2 and 3 (1st honors, 2nd honors, pass, and fail grades for group 1, 39%, 33%, 23% and 6%; group 2, 34%, 41%, 17% and 8%; group 3, 39%, 25%, 28% and 7%) (p = 0.48). An increased attendance rate at tutorials was associated with higher numbers of honors grades (p = < 0.001). Anonymous feedback from the students demonstrated considerable satisfaction with program: > 85% agreed that the online program was interactive and very educational. CONCLUSIONS: Use of online video technology, tutors of varied experience, and simulated patients were demonstrated to replicate patient encounters, and to facilitate the development of clinical skills remotely during the COVID-19 pandemic.


Asunto(s)
COVID-19 , Simulación de Paciente , Estudiantes de Medicina , Humanos , Competencia Clínica , COVID-19/epidemiología , Aprendizaje , Pandemias , Enseñanza
4.
Sci Rep ; 10(1): 15444, 2020 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-32963294

RESUMEN

Diets low in seafood omega-3 polyunsaturated fatty acids (PUFAs) are very prevalent. Such diets have recently been ranked as the sixth most important dietary risk factor-1.5 million deaths and 33 million disability-adjusted life-years worldwide are attributable to this deficiency. Wild oily fish stocks are insufficient to feed the world's population, and levels of eicosapentaenoic acid and docosahexaenoic acid (DHA) in farmed fish have more than halved in the last 20 years. Here we report on a double-blinded, controlled trial, where 161 healthy normotensive adults were randomly allocated to eat at least three portions/week of omega-3-PUFA enriched (or control) chicken-meat, and to eat at least three omega-3-PUFA enriched (or control) eggs/week, for 6 months. We show that regular consumption of omega-3-PUFA enriched chicken-meat and eggs significantly increased the primary outcome, the red cell omega-3 index (mean difference [98.75% confidence interval] from the group that ate both control foods, 1.7% [0.7, 2.6]). Numbers of subjects with a very high-risk omega-3 index (index < 4%) were more than halved amongst the group that ate both enriched foods. Furthermore, eating the enriched foods resulted in clinically relevant reductions in diastolic blood pressure (- 3.1 mmHg [- 5.8, - 0.3]). We conclude that chicken-meat and eggs, naturally enriched with algae-sourced omega-3-PUFAs, may serve as alternative dietary sources of these essential micronutrients. Unlike many lifestyle interventions, long-term population health benefits do not depend on willingness of individuals to make long-lasting difficult dietary changes, but on the availability of a range of commonly eaten, relatively inexpensive, omega-3-PUFA enriched foods.


Asunto(s)
Presión Sanguínea , Dieta , Ingestión de Alimentos/fisiología , Huevos/análisis , Ácidos Grasos Omega-3/análisis , Alimentos Fortificados , Carne/análisis , Adolescente , Adulto , Método Doble Ciego , Ingestión de Energía , Ácidos Grasos Omega-3/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Alimentos Marinos/análisis , Adulto Joven
5.
Atherosclerosis ; 269: 42-49, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29258006

RESUMEN

BACKGROUND AND AIMS: Elevated urinary 11-dehydro thromboxane B2 (TxB2), a measure of thromboxane A2 formation in vivo, predicts future atherothrombotic events. To further understand this relationship, the genetic determinants of 11-dehydro TxB2 and their associations with cardiovascular morbidity were investigated in this study. METHODS: Genome-wide and targeted genetic association studies of urinary 11-dehydro TxB2 were conducted in 806 Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) participants. RESULTS: The strongest associations were in PPARGC1B (rs4235745, rs32582, rs10515638) and CNTN4 (rs10510230, rs4684343), these 5 single nucleotide polymorphisms (SNPs) were independently associated with 11-dehydro TxB2 formation. Haplotypes of 11-dehydro TxB2 increasing alleles for both PPARGC1B and CNTN4 were significantly associated with 11-dehydro TxB2, explaining 5.2% and 4.5% of the variation in the whole cohort, and 8.8% and 7.9% in participants not taking aspirin, respectively. In a second ASCOT population (n = 6199), addition of these 5 SNPs significantly improved the covariate-only Cox proportional hazards model for cardiovascular events (chisq = 14.7, p=0.01). Two of the risk alleles associated with increased urinary 11-dehydro TxB2 were individually associated with greater incidences of cardiovascular events - rs10515638 (HR = 1.31, p=0.01) and rs10510230 (HR = 1.25, p=0.007); effect sizes were larger in those not taking aspirin. CONCLUSIONS: PPARGC1B and CNTN4 genotypes are associated with elevated thromboxane A2 formation and with an excess of cardiovascular events. Aspirin appears to blunt these associations. If specific protection of PPARGC1B and CNTN4 variant carriers by aspirin is confirmed by additional studies, PPARGC1B and CNTN4 genotyping could potentially assist in clinical decision making regarding the use of aspirin in primary prevention.


Asunto(s)
Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/genética , Proteínas Portadoras/genética , Contactinas/genética , Polimorfismo de Nucleótido Simple , Tromboxano A2/metabolismo , Anciano , Aspirina/uso terapéutico , Fármacos Cardiovasculares/uso terapéutico , Enfermedades Cardiovasculares/etnología , Enfermedades Cardiovasculares/prevención & control , Europa (Continente)/epidemiología , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Haplotipos , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Fenotipo , Prevención Primaria , Supervivencia sin Progresión , Proteínas de Unión al ARN , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Tromboxano B2/análogos & derivados , Tromboxano B2/orina , Factores de Tiempo , Población Blanca/genética
6.
J Clin Invest ; 127(5): 1798-1812, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28394258

RESUMEN

BACKGROUND: Understanding the genetic architecture of cardiac structure and function may help to prevent and treat heart disease. This investigation sought to identify common genetic variations associated with inter-individual variability in cardiac structure and function. METHODS: A GWAS meta-analysis of echocardiographic traits was performed, including 46,533 individuals from 30 studies (EchoGen consortium). The analysis included 16 traits of left ventricular (LV) structure, and systolic and diastolic function. RESULTS: The discovery analysis included 21 cohorts for structural and systolic function traits (n = 32,212) and 17 cohorts for diastolic function traits (n = 21,852). Replication was performed in 5 cohorts (n = 14,321) and 6 cohorts (n = 16,308), respectively. Besides 5 previously reported loci, the combined meta-analysis identified 10 additional genome-wide significant SNPs: rs12541595 near MTSS1 and rs10774625 in ATXN2 for LV end-diastolic internal dimension; rs806322 near KCNRG, rs4765663 in CACNA1C, rs6702619 near PALMD, rs7127129 in TMEM16A, rs11207426 near FGGY, rs17608766 in GOSR2, and rs17696696 in CFDP1 for aortic root diameter; and rs12440869 in IQCH for Doppler transmitral A-wave peak velocity. Findings were in part validated in other cohorts and in GWAS of related disease traits. The genetic loci showed associations with putative signaling pathways, and with gene expression in whole blood, monocytes, and myocardial tissue. CONCLUSION: The additional genetic loci identified in this large meta-analysis of cardiac structure and function provide insights into the underlying genetic architecture of cardiac structure and warrant follow-up in future functional studies. FUNDING: For detailed information per study, see Acknowledgments.


Asunto(s)
Sitios Genéticos , Estudio de Asociación del Genoma Completo , Cardiopatías , Miocardio , Polimorfismo de Nucleótido Simple , Carácter Cuantitativo Heredable , Femenino , Cardiopatías/genética , Cardiopatías/metabolismo , Cardiopatías/fisiopatología , Humanos , Masculino
7.
Hum Mol Genet ; 25(18): 4094-4106, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27466198

RESUMEN

It has been hypothesized that low frequency (1-5% minor allele frequency (MAF)) and rare (<1% MAF) variants with large effect sizes may contribute to the missing heritability in complex traits. Here, we report an association analysis of lipid traits (total cholesterol, LDL-cholesterol, HDL-cholesterol triglycerides) in up to 27 312 individuals with a comprehensive set of low frequency coding variants (ExomeChip), combined with conditional analysis in the known lipid loci. No new locus reached genome-wide significance. However, we found a new lead variant in 26 known lipid association regions of which 16 were >1000-fold more significant than the previous sentinel variant and not in close LD (six had MAF <5%). Furthermore, conditional analysis revealed multiple independent signals (ranging from 1 to 5) in a third of the 98 lipid loci tested, including rare variants. Addition of our novel associations resulted in between 1.5- and 2.5-fold increase in the proportion of heritability explained for the different lipid traits. Our findings suggest that rare coding variants contribute to the genetic architecture of lipid traits.


Asunto(s)
HDL-Colesterol/genética , LDL-Colesterol/genética , Metabolismo de los Lípidos/genética , Lípidos/genética , Adolescente , Adulto , Anciano , Niño , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Exoma/genética , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Humanos , Lípidos/sangre , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Triglicéridos/sangre , Triglicéridos/genética , Población Blanca
8.
Proteomics Clin Appl ; 9(5-6): 610-7, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25786980

RESUMEN

PURPOSE: We have previously demonstrated associations between the urinary proteome profile and coronary artery disease (CAD) in cross-sectional studies. Here, we evaluate the potential of a urinary proteomic panel as a predictor of CAD in the hypertensive atherosclerotic cardiovascular disease (HACVD) substudy population of the Anglo-Scandinavian Cardiac Outcomes Trial study. EXPERIMENTAL DESIGN: Thirty-seven cases with primary CAD endpoint were matched for sex and age to controls who had not reached a CAD endpoint during the study. Spot urine samples were analyzed using CE coupled to Micro-TOF MS. A previously developed 238-marker CE-MS model for diagnosis of CAD (CAD238 ) was assessed for its predictive potential. RESULTS: Sixty urine samples (32 cases; 28 controls; 88% male, mean age 64 ± 5 years) were analyzed. There was a trend toward healthier values in controls for the CAD model classifier (-0.432 ± 0.326 versus -0.587 ± 0.297, p = 0.170), and the CAD model showed statistical significance on Kaplan-Meier survival analysis p = 0.021. We found 190 individual markers out of 1501 urinary peptides that separated cases and controls (AUC >0.6). Of these, 25 peptides were also components of CAD238 . CONCLUSION AND CLINICAL RELEVANCE: A urinary proteome panel originally developed in a cross-sectional study predicts CAD endpoints independent of age and sex in a well-controlled prospective study.


Asunto(s)
Enfermedad de la Arteria Coronaria/orina , Fragmentos de Péptidos/orina , Anciano , Aterosclerosis/mortalidad , Aterosclerosis/orina , Biomarcadores/orina , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/mortalidad , Estudios Transversales , Femenino , Humanos , Hipertensión/mortalidad , Hipertensión/orina , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteoma/metabolismo , Proteómica
9.
Circ Cardiovasc Genet ; 7(6): 873-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25210050

RESUMEN

BACKGROUND: Blood pressure (BP) is highly heritable, but our understanding of the genetic causes underlying variations in BP is incomplete. In this study, we explored whether novel loci associated with BP could be identified using a genecentric approach in 3 community-based cohorts with accurate BP measurements. METHODS AND RESULTS: Genotyping of 1857 single nucleotide polymorphisms (SNPs) in 91 ion channel genes was performed in a discovery cohort (n=358). Thirty-four SNPs associated with BP traits (P≤0.01) were followed up in an independent population (n=387); significant SNPs from this analysis were looked up in another independent population (n=1010) and meta-analyzed. Repeated clinic and ambulatory measurements were available for all but the discovery cohort (clinic only). Association analyses were performed, with systolic, diastolic, and pulse pressures as quantitative traits, adjusting for age and sex. Quantile-quantile plots indicated that the genecentric approach resulted in an inflation of association signals. Of the 29 SNPs taken forward from the discovery cohort, 2 SNPs were associated with BP phenotypes with the same direction of effect, with experiment-wide significance, in follow-up cohort I. These were rs2228291, in the chloride channel gene CLCN2, and rs10513488, in the potassium channel gene KCNAB1. Both associations were subsequently replicated in follow-up cohort II. CONCLUSIONS: Using a genecentric design and 3 well-phenotyped populations, this study identified 2 previously unreported, biologically plausible, genetic associations with BP. These results suggest that dense genotyping of genes, in pathways known to influence BP, could add to candidate-gene and Genome Wide Association studies in further explaining BP heritability.


Asunto(s)
Presión Sanguínea/genética , Canales Iónicos/genética , Adulto , Alelos , Canales de Cloruro CLC-2 , Canales de Cloruro/genética , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Canal de Potasio Kv1.3/genética , Masculino , Persona de Mediana Edad , Fenotipo , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
10.
J Lipid Res ; 53(5): 1000-1011, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22368281

RESUMEN

We carried out a genome-wide association study (GWAS) of LDL-c response to statin using data from participants in the Collaborative Atorvastatin Diabetes Study (CARDS; n = 1,156), the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT; n = 895), and the observational phase of ASCOT (n = 651), all of whom were prescribed atorvastatin 10 mg. Following genome-wide imputation, we combined data from the three studies in a meta-analysis. We found associations of LDL-c response to atorvastatin that reached genome-wide significance at rs10455872 (P = 6.13 × 10(-9)) within the LPA gene and at two single nucleotide polymorphisms (SNP) within the APOE region (rs445925; P = 2.22 × 10(-16) and rs4420638; P = 1.01 × 10(-11)) that are proxies for the ε2 and ε4 variants, respectively, in APOE. The novel association with the LPA SNP was replicated in the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) trial (P = 0.009). Using CARDS data, we further showed that atorvastatin therapy did not alter lipoprotein(a) [Lp(a)] and that Lp(a) levels accounted for all of the associations of SNPs in the LPA gene and the apparent LDL-c response levels. However, statin therapy had a similar effect in reducing cardiovascular disease (CVD) in patients in the top quartile for serum Lp(a) levels (HR = 0.60) compared with those in the lower three quartiles (HR = 0.66; P = 0.8 for interaction). The data emphasize that high Lp(a) levels affect the measurement of LDL-c and the clinical estimation of LDL-c response. Therefore, an apparently lower LDL-c response to statin therapy may indicate a need for measurement of Lp(a). However, statin therapy seems beneficial even in those with high Lp(a).


Asunto(s)
LDL-Colesterol/sangre , Estudio de Asociación del Genoma Completo , Ácidos Heptanoicos/farmacología , Pirroles/farmacología , Receptores del Ácido Lisofosfatídico/genética , Adulto , Anciano , Atorvastatina , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Femenino , Genotipo , Glucosiltransferasas/genética , Ácidos Heptanoicos/uso terapéutico , Humanos , Hipertensión/sangre , Hipertensión/tratamiento farmacológico , Hipertensión/genética , Masculino , Persona de Mediana Edad , Efecto Placebo , Polimorfismo de Nucleótido Simple/genética , Pirroles/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
11.
Hypertension ; 59(2): 248-55, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22184326

RESUMEN

Essential hypertension is a multifactorial disorder and is the main risk factor for renal and cardiovascular complications. The research on the genetics of hypertension has been frustrated by the small predictive value of the discovered genetic variants. The HYPERGENES Project investigated associations between genetic variants and essential hypertension pursuing a 2-stage study by recruiting cases and controls from extensively characterized cohorts recruited over many years in different European regions. The discovery phase consisted of 1865 cases and 1750 controls genotyped with 1M Illumina array. Best hits were followed up in a validation panel of 1385 cases and 1246 controls that were genotyped with a custom array of 14 055 markers. We identified a new hypertension susceptibility locus (rs3918226) in the promoter region of the endothelial NO synthase gene (odds ratio: 1.54 [95% CI: 1.37-1.73]; combined P=2.58 · 10(-13)). A meta-analysis, using other in silico/de novo genotyping data for a total of 21 714 subjects, resulted in an overall odds ratio of 1.34 (95% CI: 1.25-1.44; P=1.032 · 10(-14)). The quantitative analysis on a population-based sample revealed an effect size of 1.91 (95% CI: 0.16-3.66) for systolic and 1.40 (95% CI: 0.25-2.55) for diastolic blood pressure. We identified in silico a potential binding site for ETS transcription factors directly next to rs3918226, suggesting a potential modulation of endothelial NO synthase expression. Biological evidence links endothelial NO synthase with hypertension, because it is a critical mediator of cardiovascular homeostasis and blood pressure control via vascular tone regulation. This finding supports the hypothesis that there may be a causal genetic variation at this locus.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Hipertensión/genética , Óxido Nítrico Sintasa de Tipo III/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Europa (Continente) , Femenino , Predisposición Genética a la Enfermedad/etnología , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Hipertensión/etnología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas
12.
J Renin Angiotensin Aldosterone Syst ; 12(4): 504-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21490025

RESUMEN

Angiotensin II, a vasoconstrictor and the main effector molecule of the renin-angiotensin system, is known to influence inflammation, thrombosis, low-density lipoprotein oxidation and growth factors, all of which contribute to cardiovascular disease. The associations of polymorphisms in the angiotensin-converting enzyme 2 (ACE2) gene with cardiovascular risk have not been fully determined. Single nucleotide polymorphisms (SNPs) in ACE2 were genotyped in participants of the prospective MORGAM study (n = 5092) from five cohorts: ATBC, FINRISK, Northern Sweden, PRIME/Belfast and PRIME/France. Using a case-cohort design, associations were sought between SNPs and haplotypes with cardiovascular events during follow-up (Cox proportional hazards model). The comparison group were a subset of all MORGAM participants who were selected to ensure similar age and sex distributions among the cases and controls. The A allele of the rs2285666 SNP (HR = 0.3, p = 0.04) was significantly associated with the risk of cardiovascular death in female subjects. These findings complement those found in other studies of SNPs in the ACE2 gene in relation to cardiovascular disease risk. As females carry two copies of the ACE2 gene, and given its plausible biological role in cardiovascular disease risk, further studies of ACE2 should be prioritized.


Asunto(s)
Enfermedades Cardiovasculares/enzimología , Enfermedades Cardiovasculares/genética , Predisposición Genética a la Enfermedad , Peptidil-Dipeptidasa A/genética , Polimorfismo de Nucleótido Simple/genética , Enzima Convertidora de Angiotensina 2 , Presión Sanguínea , Enfermedades Cardiovasculares/fisiopatología , Estudios de Cohortes , Intervalos de Confianza , Femenino , Estudios de Seguimiento , Haplotipos/genética , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Análisis de Supervivencia
13.
J Appl Physiol (1985) ; 110(2): 468-71, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21088211

RESUMEN

Dietary salt intake is associated with high brachial blood pressure (BP) and increased risk of cardiovascular disease. We investigated whether changes in dietary salt intake are associated with changes in central BP and wave reflection in healthy volunteers. Ten healthy normotensive male volunteers (22-40 yr) participated in a 6-wk double-blind randomized crossover study to compare a low-dietary salt intake (60-80 mmol sodium/day) with a high-salt intake (low salt intake supplemented with 128 mmol sodium/day) on central BP and wave reflection. Brachial and carotid BP, carotid blood flow velocity, forward (P(f)) and backward (P(b)) pressure, wave intensity, body weight, and urinary electrolyte excretion were measured at the end of each crossover period. High salt intake significantly increased carotid systolic BP [98 (SD 11) vs. 91 mmHg (SD 13), P < 0.01] and increased wave reflection [ratio of backward to forward pressure (P(b)/P(f)) 0.13 (SD 0.02) vs. 0.11 (SD 0.03), P = 0.04] despite only small effects on brachial BP [114 (SD 9) vs. 112 mmHg (SD 6), P = 0.1]. Urinary sodium excretion and body weight were also increased following high salt intake. High salt intake disproportionately increases central BP compared with brachial BP as a result of enhanced wave reflection. These effects may contribute to the adverse effect of high dietary salt intake on the risk of cardiovascular disease.


Asunto(s)
Presión Sanguínea/fisiología , Arterias Carótidas/fisiología , Flujo Pulsátil/fisiología , Cloruro de Sodio Dietético/metabolismo , Adulto , Velocidad del Flujo Sanguíneo/fisiología , Estudios Cruzados , Método Doble Ciego , Humanos , Masculino , Adulto Joven
14.
Artery Res ; 4(3): 75-80, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21072124

RESUMEN

Conventionally, the relationship between parent and daughter vessels at vascular bifurcations has been expressed by the junction exponent (x), and deviations of this parameter from the optimal conditions predicted by Murray's law (x = 3) have been shown to be associated with vascular disease. However, the junction exponent is normally calculated iteratively from diameter measurements, and Monte-Carlo simulation studies show the junction exponent to be biased in the presence of measurement noise.We present an alternative parameter, referred to as optimality ratio, that is simpler to compute and also more robust in the presence of noise.To demonstrate the sensitivity of the optimality ratio to alterations in topography of the retinal vascular network, we analysed the effect of inducing endothelial dysfunction by infusion of NG-monomethyl-l-arginine (l-NMMA), a nitric oxide synthase inhibitor, compared to placebo in a double-blind crossover study. The optimality ratio showed a significant increase (p = 0.03) during infusion of l-NMMA compared to placebo.We propose that a measure of the extent of departure of optimality ratio from its optimal value of 2(-1/3) may be a useful indicator of microvascular endothelial dysfunction in vivo.

15.
J Am Coll Cardiol ; 55(17): 1875-81, 2010 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-20413040

RESUMEN

OBJECTIVES: We hypothesized that an amlodipine-based regimen would have more favorable effects on left ventricular (LV) diastolic function. BACKGROUND: Different antihypertensive therapies may vary in their effect on LV diastolic function. METHODS: The HACVD (Hypertension Associated Cardiovascular Disease) substudy of ASCOT (Anglo-Scandinavian Cardiac Outcomes Trial) collected detailed cardiovascular phenotypic data on a subset of 1,006 participants recruited from 2 centers (St. Mary's Hospital, London, and Beaumont Hospital, Dublin). Conventional and tissue Doppler echocardiography and measurement of plasma B-type natriuretic peptide (BNP) were performed approximately 1 year after randomization to atenolol-based or amlodipine-based antihypertensive treatment to assess LV diastolic function. RESULTS: On-treatment blood pressure (BP) (mean +/- SD) was similar in both groups: atenolol-based regimen, systolic BP of 137 +/- 17 mm Hg, diastolic BP of 82 +/- 9 mm Hg; amlodipine-based regimen, systolic BP of 136 +/- 15 mm Hg, diastolic BP of 80 +/- 9 mm Hg. Ejection fraction did not differ between groups, but early diastolic mitral annular velocity (E'), a measure of diastolic relaxation, was lower in patients on the atenolol-based regimen: atenolol-based regimen, 7.9 +/- 1.8; amlodipine-based regimen, 8.8 +/- 2.0. A measure of left ventricular filling pressure, E/E', and BNP were significantly higher in patients on the atenolol-based regimen. Differences in E', E/E', and BNP remained significant after adjustment for age and sex. Further adjustment for systolic BP, LV mass index, and heart rate had no impact on differences in mean E' or BNP. The difference in E/E' was attenuated. CONCLUSIONS: Patients receiving treatment with an amlodipine-based regimen had better diastolic function than patients treated with the atenolol-based regimen. Treatment-related differences in diastolic function were independent of BP reduction and other factors that are known to affect diastolic function.


Asunto(s)
Amlodipino/farmacología , Antihipertensivos/farmacología , Atenolol/farmacología , Función Ventricular Izquierda/efectos de los fármacos , Amlodipino/uso terapéutico , Antihipertensivos/uso terapéutico , Atenolol/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Diástole/efectos de los fármacos , Ecocardiografía Doppler , Femenino , Humanos , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre
16.
Circ Cardiovasc Genet ; 3(1): 53-9, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20160196

RESUMEN

BACKGROUND: Studies of knockout and transgenic mice have demonstrated key roles for genes encoding components of the renin angiotensin system in blood pressure regulation. However, whether polymorphisms in these genes contribute to the cause of essential hypertension in humans is still a matter of debate. METHODS AND RESULTS: We performed an experiment with dense tagging single-nucleotide polymorphism coverage of 4 genes encoding proteins that control the overall activity of the cascade, namely renin, angiotensinogen, angiotensin-converting enzyme, and angiotensin-converting enzyme 2, in 2 Irish populations. Both clinic and 24-hour ambulatory blood pressure measurements were available from population I (n=387), whereas just clinic blood pressure was measured in population II (n=1024). Of the 23 polymorphisms genotyped, only a single renin gene polymorphism, REN-5312C/T, showed consistent statistically significant associations with elevated diastolic pressures. Carriage of one REN-5312T allele was associated with the following age- and sex-adjusted increments in diastolic pressures (mean [95% CI]): population I, clinic, 1.5 mm Hg (0.3 to 2.8); daytime, 1.4 mm Hg (0.4 to 2.4); night-time, 1.3 mm Hg (0.4 to 2.3), and population II, clinic, 1.1 mm Hg (0.1 to 2.1). Haplotypic analyses and multivariate stepwise regression analyses were in concordance with individual single-nucleotide polymorphism analyses. CONCLUSIONS: The REN-5312T allele had been shown previously to result in increased in vitro expression of the renin gene. We have now shown, in 2 independent populations, that carriage of a REN-5312T allele is associated with elevated diastolic blood pressure. These data provide evidence that renin is an important susceptibility gene for arterial hypertension in whites.


Asunto(s)
Presión Sanguínea/genética , Hipertensión/genética , Renina/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Enzima Convertidora de Angiotensina 2 , Angiotensinógeno/genética , Femenino , Genotipo , Haplotipos , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Peptidil-Dipeptidasa A/genética , Polimorfismo de Nucleótido Simple , Análisis de Regresión , Sistema Renina-Angiotensina/genética , Población Blanca/genética
17.
Hypertension ; 55(1): 54-60, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19917876

RESUMEN

Angiotensin receptor blockers, angiotensin-converting enzyme inhibitors, and diuretics all cause reactive rises in plasma renin concentration, but particularly high levels have been reported with aliskiren. This prompted speculation that blockade of plasma renin activity with aliskiren could be overwhelmed, leading to paradoxical increases in blood pressure. This meta-analysis of data from 4877 patients from 8 randomized, double-blind, placebo- and/or active-controlled trials examined this hypothesis. The analysis focused on the incidence of paradoxical blood pressure increases above predefined thresholds, after > or =4 weeks of treatment with 300 mg of aliskiren, angiotensin receptor blockers (300 mg of irbesartan, 100 mg of losartan, or 320 mg of valsartan), 10 mg of ramipril, 25 mg of hydrochlorothiazide, or placebo. There were no significant differences in the frequency of increases in systolic (>10 mm Hg; P=0.30) or diastolic (>5 mm Hg; P=0.65) pressure among those treated with aliskiren (3.9% and 3.1%, respectively), angiotensin receptor blockers (4.0% and 3.7%), ramipril (5.7% and 2.6%), or hydrochlorothiazide (4.4% and 2.7%). Increases in blood pressure were considerably more frequent in the placebo group (12.6% and 11.4%; P<0.001). None of the 536 patients with plasma renin activity data who received 300 mg of aliskiren exhibited an increase in systolic pressure >10 mm Hg that was associated with an increase in plasma renin activity >0.1 ng/mL per hour. In conclusion, the incidence of blood pressure increases with aliskiren was similar to that during treatment with other antihypertensive drugs. Blood pressure rises on aliskiren treatment were not associated with increases in plasma renin activity. This meta-analysis found no evidence that aliskiren uniquely causes paradoxical rises in blood pressure.


Asunto(s)
Amidas/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Fumaratos/uso terapéutico , Hipertensión/tratamiento farmacológico , Adulto , Anciano , Amidas/efectos adversos , Antihipertensivos/efectos adversos , Antihipertensivos/uso terapéutico , Fumaratos/efectos adversos , Humanos , Hipertensión/sangre , Hipertensión/fisiopatología , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Renina/antagonistas & inhibidores , Renina/sangre , Resultado del Tratamiento
18.
Eur Heart J ; 31(6): 747-52, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19942604

RESUMEN

AIMS: Patients with controlled hypertension are at risk of future cardiac events, but predicting first events remains difficult. We hypothesized that modern echocardiographic measures of left ventricular diastolic function may be more sensitive than traditional echocardiographic methods of risk prediction and set out to test this in a cohort of patients with well-controlled hypertension. METHODS AND RESULTS: Conventional and tissue Doppler echocardiography was performed on 980 participants in the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT). All subjects had hypertension, but no known cardiac disease. Cardiac events were defined as fatal and non-fatal myocardial infarction (including silent myocardial infarction), coronary revascularization procedures, new-onset angina (stable or unstable), fatal and non-fatal heart failure, and life-threatening arrhythmias. Analysis was performed by a single, blinded observer. There were 56 primary cardiac events during 4.2 +/- 0.7 years follow-up. The ratio of transmitral Doppler early filling velocity to tissue Doppler early diastolic mitral annular velocity (E/E') was the strongest predictor of first cardiac events in Cox-proportional hazards models. Following adjustment for covariates, a unit rise in the E/E' ratio was associated with a 17% increment in risk of a cardiac event (HR 1.17, CI 1.05-1.29; P = 0.003). CONCLUSION: Tissue Doppler E/E', a non-invasive estimate of left atrial filling pressure, independently predicts primary cardiac events in a hypertensive population and out-performed traditional echocardiographic measures in this moderately sized, well-treated hypertensive population. E/E' represents a simple, effective tool for assessing cardiac risk in a hypertensive population.


Asunto(s)
Ecocardiografía Doppler/métodos , Cardiopatías/diagnóstico por imagen , Hipertensión/complicaciones , Adulto , Anciano , Antihipertensivos/uso terapéutico , Diagnóstico Precoz , Femenino , Cardiopatías/etiología , Humanos , Hipertensión/tratamiento farmacológico , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Medición de Riesgo
19.
J Hypertens ; 27(4): 876-85, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19516185

RESUMEN

BACKGROUND: Results of the Anglo-Scandinavian cardiac outcomes trial-blood pressure lowering arm (ASCOT-BPLA) showed significantly lower rates of coronary and stroke events in individuals allocated an amlodipine-perindopril combination drug regimen than in those allocated an atenolol-thiazide combination drug regimen. The aims of the ambulatory blood pressure (ABP) substudy of ASCOT were to examine the impact of the two blood pressure (BP)- lowering regimens on ambulatory pressures, test to what extent the between-treatment differences in cardiovascular outcome could be attributed to differences in ABP and assess whether ABP provides predictive information additional to that of clinic blood pressure (CBP) in treated hypertensive patients. METHODS AND RESULTS: One thousand, nine hundred and five patients from four ASCOT centres had repeated ABPs performed over a median follow-up period of 5.5 years. As in the whole ASCOT population, CBP values were lower in amlodipine-perindopril-treated patients compared with those treated with atenolol-thiazide [between-regimen difference [95% confidence intervals (CIs)]]: [-1.5 (-2.4 to -0.5)/-1.2 (-1.8 to +0.5) mmHg]. Daytime BP during follow-up was higher in patients treated with amlodipine-perindopril therapy [+1.1 (0.1-2.1)/+1.6 (0.8-2.3) mmHg]; night-time systolic, but not diastolic BP, was lower in patients treated with amlodipine-perindopril therapy [-2.2 (-3.4 to +0.9)/+0.8 (0.0-1.6) mmHg]. The relative risk of a cardiovascular event associated with a 1 SD increment in accumulated mean BP was 1.35 (1.18-1.53) for clinic systolic BP, 1.30 (1.14-1.49) for daytime systolic BP and 1.42 (1.24-1.62) for night-time systolic BP. With adjustment for baseline variables, treatment regimen and clinic systolic BP, the hazard ratios were 1.17 (1.00-1.36) and 1.25 (1.08-1.47) for daytime and night-time systolic BP, respectively. The between-regimen adjusted hazard ratio for cardiovascular events (amlodipine-perindopril therapy versus atenolol-thiazide therapy) was 0.74 (0.55-1.01) and increased to 0.81 (0.60-1.10) after further adjustment for clinic systolic BP. Further, adjustment for night-time systolic BP increased the hazard ratio to 0.85 (0.62-1.16). CONCLUSION: The amlodipine-perindopril and atenolol-thiazide regimens had different effects on daytime and night-time ABP, which may have contributed to the lower rates of events in patients treated with amlodipine-perindopril therapy. Both CBP and ABP were significantly associated with rates of cardiovascular events. ABP nocturnal pressures provided complimentary and incremental utility over CBP in the prediction of cardiovascular risk in treated hypertensive patients. These data support the use of ABP to assess the effect of antihypertensive treatment in clinical practice.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Hipertensión/tratamiento farmacológico , Anciano , Amlodipino/administración & dosificación , Atenolol/administración & dosificación , Quimioterapia Combinada , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Perindopril/administración & dosificación , Estudios Prospectivos , Tiazidas/administración & dosificación
20.
Am J Hypertens ; 22(9): 954-7, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19556972

RESUMEN

Hypertensive patients with low-baseline plasma renin activity (PRA) are known to respond best to natriuretic drugs, and those with high PRA respond best to renin-angiotensin system (RAS) blockade. However, there has been recent speculation that blood pressure (BP)-lowering responses to the renin inhibitor, aliskiren, might also be blunted in some patients with medium-to-high baseline PRA. It has been suggested that treatment resistance in these patients may result from excessive reactive increases in renin secretion, such that aliskiren's blockade of PRA is overwhelmed. In order to test for evidence in support of this hypothesis, we conducted a reanalysis of original data from three published clinical trials of aliskiren. When aliskiren was administered as a monotherapy, or in combination with other blockers of the RAS, changes in PRA were closely correlated with baseline PRA. Patients with low-baseline PRA demonstrated small reductions or rises in PRA, rather than patients with medium-to-high baseline PRA. We confirmed that ambulatory BP-lowering responses to full dose aliskiren monotherapy were greatest and least among patients with high- and low-baseline PRA, respectively. However no such association was demonstrated during aliskiren combination therapy. With either monotherapy or combination therapy, no patient with a baseline PRA >0.65 ng/ml/h was observed to have a rise in both PRA and BP. We conclude, therefore, that there is only evidence for one type of resistance to aliskiren--as with all blockers of the RAS, lesser BP-lowering responses to aliskiren occur in those with the least renin to block.


Asunto(s)
Amidas/uso terapéutico , Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Fumaratos/uso terapéutico , Hipertensión/tratamiento farmacológico , Renina/sangre , Amidas/administración & dosificación , Antihipertensivos/administración & dosificación , Compuestos de Bifenilo/uso terapéutico , Quimioterapia Combinada , Fumaratos/administración & dosificación , Humanos , Irbesartán , Ramipril/uso terapéutico , Renina/antagonistas & inhibidores , Sistema Renina-Angiotensina/efectos de los fármacos , Tetrazoles/uso terapéutico , Resultado del Tratamiento
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