The extent of hypertension research is faithfully mirrowed by the Journal of Hypertension, which also covers a series of different aspects of hypertension research in this issue, going from blood pressure measurements to benefits and limitations of antihypertensive therapy.
Three groups of experts on children hypertension (Chiolero et al., pp. 1352–1355; Bianchetti et al., pp. 1356–1358; Stergiou et al., pp. 1359–1363) present partly different opinions on a recent international controversy raised by the US Preventive Services Task Force, stating that ‘current evidence is insufficient to assess the balance of benefits and harms of screening for primary hypertension in asymptomatic children and adolescents’. It is no surprise that this statement has raised a hot controversy, which is well represented by the wide range of different opinions expressed by the three groups of authors of the editorials published here, these differences also depending on the perspective from which each group of authors has tried to see the problem – that of public health, that of the practicing physician and that of the investigator.
The question is of utmost importance, obviously, and the Journal of Hypertension plans to host other contributions from authoritative experts of the field in forthcoming issues. A modest personal comment is that the US Preventive Services Task Force document should be taken for what it is – a statement rather than a recommendation. The statement simply says that ‘current evidence is insufficient’, but we should not forget ‘lack of evidence’ is quite another thing than evidence against, – it is a recognition that the area is open to controversial opinions, and the Journal of Hypertension is delighted to contribute in this and subsequent issues towards the progress of evidence, and evidence often progresses through controversy.
Other papers in the current issue of the Journal are focused on the clinical value of blood pressure measurement. A report from the Dublin Outcome Study (Draman et al., pp. 1373–1377) shows the usefulness of 24-h ambulatory blood pressure monitoring in hypertensive patients with diabetes: their SBP was higher than in patients without diabetes during night time, but not during the daytime, the night-time increase accounting substantially for the increased mortality of diabetic hypertensive patients during a 5.3-year follow-up. In a pilot group of elderly individuals, central pulse pressure, but not peripheral blood pressure, was found to correlate significantly with positron emission tomography measurements of brain metabolism (Verger et al., pp. 1378–1385). Finally, a large and accurate study on blood pressure values achieved during exercise in normotensive individuals followed up during 3 years has established cut-off values predicting the likelihood of incident hypertension (Lorbeer et al., pp. 1386–1393). In an accompanying editorial, Parati and Zhang (pp. 1364–1367) discuss whether exaggerated elevation of exercise blood pressure may indicate a masked hypertension and suggest ambulatory blood pressure monitoring.
Another group of papers deals with therapeutic aspects. Thomopoulos et al. (pp. 1321–1341) continue with their series of updated meta-analyses on the effect of blood pressure-lowering treatment on fatal and nonfatal cardiovascular events, with a paper on head-to-head comparisons of different classes of agents. They show the effects of all drug classes are not significantly different on most outcomes when their blood pressure effect is equivalent. This does not allow the formulation of a fixed paradigm of drug choice valuable for all hypertensive patients. However, there are also some significant differences involving almost all classes of drugs, which may suggest specific choices under specific conditions. If prevention of stroke is clearly one of the major benefits of antihypertensive treatment, acute stroke remains a condition in which the blood pressure-lowering does not appear to favourably influence survival and functional outcome. Hornslien et al. (pp. 1487–1491) publish now further data from the Scandinavian Candesartan Acute Stroke Trial (SCAST), showing that in this trial blood pressure-lowering treatment with candesartan also had no beneficial effect on activities of daily living and level of care at 6 months. Okin et al. (pp. 1480–1486), using the large database provided by the Losartan Intervention for Endpoint reduction in hypertension (LIFE) trial, have brought further data to the recent debate on the possible association of digoxin with mortality when used in patients with atrial fibrillation. They report that, in the hypertensive patients with left ventricular hypertrophy of the LIFE trial with atrial fibrillation, digoxin use was not associated with significantly increased risk of all-cause mortality, provided that careful adjustment was done for a large numbers of other predictors of death. In an accompanying commentary, Kahan (pp. 1371–1372) points out the authors should be commended for their efforts to adjust for potential confounders, but that, as always, great care should be taken in extending the implications of the results outside the study population actually examined. Finally, another paper with potential therapeutic implication is published by Rubattu et al. (pp. 1465–1479), showing that administration of Brassica oleracea sprouts juice could prevent renal damage in salt-loaded stroke-prone spontaneously hypertensive rats, independently of blood pressure changes, through stimulation of the AMPK/SIRT1/PGClα/PPARα/UCP2 axis.
Another consistent group of papers in this issue is focused on blood vessel changes. Gishti et al. (pp. 1429–1437) present data from the Generation R Study – a population-based prospective cohort of children studied during pregnancy, at birth and up to 6 years of age, reporting that preterm birth and accelerated infant growth are associated with narrower retinal arteriolar calibre in childhood. Cunha et al. (pp. 1438–1445) report pulse wave velocity (PWV) values higher than expected in a sample of the North Portuguese population in which prevalence of hypertension and incidence of stroke are high. Kozakova et al. (pp. 1446–1451) compared segmental carotid–femoral PWV and local carotid PWV in a cohort of healthy individuals, and found that, although both PWVs are age-dependent, the age-related increase follows different patterns in the two vascular segments. Wang et al. (pp. 1452–1457) investigated which type of blood pressure is more closely associated with intracranial arterial stenosis in the Asymptomatic Polyvascular Abnormalities in Community (APAC) study in China, and report that systolic, mean and pulse pressures are all significantly associated, but pulse pressure appears to be a more sensitive index. De Groote et al. (pp. 1342–1351) publish a thorough review of arterial hypertension in Turner's syndrome, and describe the relationship between blood pressure and aortic dilatation and dissection, the incidence of which is characteristically increased in this chromosomal disorder.
An additional group of papers in this journal issue is related to pathophysiological aspects. Rebholz et al. (pp. 1394–1400) report that among participants in the Genetic Epidemiology Network of Salt Sensitivity (GenSalt) study, urinary angiotensinogen levels are significantly associated with blood pressure sodium sensitivity. If urinary angiotensinogen can be taken as an index of intrarenal renin–angiotensin system activity, this activity may be suggested to play an important role in developing salt-sensitive hypertension. These interesting observations are commented in an accompanying editorial by Burnier (pp. 1368–1370), who suggests the GenSalt database, apart from and beyond providing evidence of an association between urinary angiotensinogen excretion and blood pressure salt-sensitivity, should be used to evaluate the predictive values of urinary angiotensinogen to identify salt-sensitive individuals, thus providing a potential marker of salt-sensitivity. Zhang et al. (pp. 1401–1410) report that elevation of endogenous angiotensin II in the nodose ganglion contributes to impairment of the arterial baroreflex function in rats with chronic heart failure through inhibiting Nav channels. Seravalle et al. (pp. 1411–1417) have found that not only established hypertension, but also high normal blood pressure is a condition accompanied by sympathetic activation, but this appears to be triggered by metabolic (increased HOMA index) rather than baroreflex alterations. Salman et al. (pp. 1418–1428) have investigated the mechanisms underlying baroreflex dysfunction in female Lewis polycystic kidney (LPR) rats, and found baroreflex dysfunction results from impaired central processing of the reflex. As atrial natriuretic peptide (ANP) deficiency has been implicated in the pathogenesis of obesity-associated cardiovascular and metabolic disease, Haufe et al. (pp. 1458–1464) investigated the effects on ANP of diet-induced weight reduction and of physical exercise, and conclude that physical exercise acutely increases ANP release in obese individuals, whereas modest diet-induced weight loss primarily affects ANP clearance mechanisms. According to the authors, combined diet-induced weight loss and physical exercise may be particularly efficacious in reversing obesity-associated ANP deficiency.
Finally, I would like to call the readers’ attention to the obituary in memoriam of John H. Laragh, written by two of his former associates, Hans Brunner and Haralambos Gavras. John H. Laragh has been one of the most outstanding personalities in hypertension research during the past 50 years, and the Editor of the Journal of Hypertension, together with the whole Editorial Board, would like to express their feelings of sympathy and admiration to John's wife and family.
Conflicts of interest
There are no conflicts of interest.