Maria Jose Fabia

Antihypertensive activity of angiotensin II AT1 receptor antagonists: a systematic review of studies with 24 h ambulatory blood pressure monitoring.

Objective To perform a systematic review of the antihypertensive activity of the angiotensin II AT1 receptor antagonists (ARB). Methods Studies in which blood pressure (BP) was measured using ambulatory BP monitoring for at least 24 h were collected from MEDLINE. Data for each treatment group, ARB, placebo or the drug used for its comparison were obtained from the selected studies. Only studies with a minimum of quality criteria were selected. The final study group contained 36 publications, with a total of 47 patient cohorts receiving ARB in monotherapy, 10 with placebo, 10 with amlodipine, and five with enalapril. The reduction in clinical and ambulatory BP during 24 h, day, night and the last 4-h period for each of the drugs analysed were calculated and adjusted by age, sex, number of participants and by the initial BP level. Results The global antihypertensive activity of ARB differs from that observed with amlodipine in the sense that the magnitude of the reduction in the BP values does not essentially depend on the initial BP values nor on the dose used. When only ARB were considered, the drug used was a determinant for systolic BP reduction, whereas for diastolic BP the influence was on the BP reduction and the duration of the antihypertensive activity. The dose used had a particular influence on the duration of the antihypertensive activity for both systolic and diastolic BP. Conclusion Among the ARB, the influence is on duration more than on the magnitude of BP reduction. Dose, therefore, is an important factor in the duration of antihypertensive activity.

Renin polymorphisms and haplotypes are associated with blood pressure levels and hypertension risk in postmenopausal women

Background Renin is a key protein of the renin–angiotensin system involved in the physiological control of blood pressure; the renin gene is therefore a candidate for essential hypertension in humans. We tested the association between polymorphisms and haplotypes of the renin gene and the risk of hypertension and blood pressure levels in two Spanish populations. Methods Two population-based studies from different regions of Spain were performed. Study A included 1502 individuals (748 women) 40–70 years old, and Study B included 670 women 45–70 years old. Fourteen polymorphisms of the renin gene were selected based on position, spacing, heterozygosity (> 10% for the minor allele frequency) and previous information, and were assessed by SNPlex. Results Genotype GG of the rs5707 polymorphism was significantly associated with blood pressure levels (P = 0.005) and with the risk of having hypertension (odds ratio, 6.16; 95% confidence interval, 1.19–31.8) in women 40–70 years old from study A, but not the men. This association was also present in the women of study B (P < 0.001 for blood pressure values; odds ratio, 2.11 and 95% confidence interval, 1.07–4.17 for hypertension). Two haplotypes defined by five selected polymorphisms were associated with increased risk of hypertension in these aged women. Conclusion Polymorphisms of the renin gene were associated with blood pressure levels and risk of hypertension in women over 40 years old. The interaction between the potential functional impact of this genetic background and the estrogen fall could explain the association in women of this age group.

Efficacy in angiotensin receptor blockade: a comparative review of data with olmesartan

A range of angiotensin II receptor blockers (ARB) is available, and analyses suggest there are differences between agents in terms of antihypertensive efficacy and 24-hour blood pressure control.This review assesses the data comparing olmesartan with other ARBs in terms of blood pressure reductions, goal achievement, 24-hour control and speed of onset. Olmesartan seems to have a more favourable efficacy profile relative to standard doses of the ARBs used in comparative studies; results consistent with the high degree of blockade of the angiotensin II type 1 receptor for olmesartan.Taken together, there might be differences between ARBs regarding their blood pressure lowering efficacy, and these results may provide further support of the benefits of olmesartan therapy since choice of an effective agent is crucial in antihypertensive therapy.

Factores que influyen en la diferencia de medida de presión arterial entre el método auscultatorio y el oscilométrico

Fundamento y objetivo El metodo auscultatorio mediante esfigmomanometro de mercurio esta siendo sustituido por otros metodos de medida de presion arterial, de los que el mas utilizado es el oscilometrico. Se analiza las posibles discrepancias de medida entre ambos metodos y los factores que influyen en ellas. Material y metodo Se obtuvieron medidas de presion arterial (PA) mediante esfigmomanometro de mercurio, con un monitor Spacelabs, en el mismo brazo y mediante un metodo secuencial. La relacion entre ambas medidas se analizo mediante los coeficientes de correlacion de Pearson y el metodo de Bland y Altman. Se calcularon las diferencias entre ambos metodos de medida. Se analizo los factores que influyen en las diferencias mediante regresion lineal multiple. Resultados Se incluyo a 1.742 sujetos adultos. El coeficiente de correlacion intraclase entre los valores obtenidos por metodo auscultatorio y los del oscilometrico fue 0,927 para la PA sistolica (PAS), 0,922 para la PA diastolica (PAD), 0,886 para la presion de pulso (PP) y 0,962 para la frecuencia de pulso (FP). Con el metodo oscilometrico se sobrestimo los valores medios de PAS mas bajos, tendencia que se invirtio para valores elevados de PAS. Aunque hubo una tendencia similar para la PAD, fue de menor magnitud. El factor que explicaba un 24% de la variancia de las diferencias de la PAS fue la PP obtenida por esfigmomanometro, mientras que para las diferencias de la PAD fue el perimetro del brazo lo que explicaba el 8% de la variancia. Conclusiones Al utilizar monitores oscilometricos, se debe considerar que los valores extremos de amplitud de pulso y perimetro del brazo pueden inducir discrepancias importantes en las medidas de PA.