This month issue of the Journal of Hypertension opens with the publication of the new guidelines on the management of hypertension and related morbidities in Latin America, prepared by a Task Force of the Latin American Society of Hypertension (pp. 1529–1545). The Journal of Hypertension is proud to be the forum chosen for dissemination of hypertension guidelines from different parts of the world, particularly when, as is the case for the Latin American guidelines, these are not subtle variations in the usual cosmopolitan recommendations on the management of hypertension, but focus on peculiarities of hypertension and cardiovascular and renal disease in Latin America, a continent dominated by disparities in social and economic conditions and great differences in health systems and availability of health care, with the widest range of lifestyles from the old traditional ones in the villages of the Amazonian forest, or the Andinean mountains to those in a modern metropolis.
Methodologies for preparation of guidelines have become the subject of controversy, however, and we also publish two editorials debating some of these issues. Messerli, heading an impressive number of hypertension authorities, raises the point that nowadays some guidelines, such as those recently prepared by the American College of Physicians and the American Academy of Family Physicians, exclude medical experts from the writing panel and commit the task to experts in statistics and in technicalities of guidelines preparation (pp. 1564–1566). In a commentary to this commentary, Chalmers (pp. 1567–1568) underlines the pros and cons of the two different approaches to guidelines, suggesting that, particularly in the area of common diseases, a cooperation between scientific experts and those who have experience in dealing with the disease in primary practice appears as a reasonable solution. In an Editor's corner of several years ago , I raised the question whether guidelines should be based either on evidence or wisdom, and suggested recommendations should be based on evidence whenever evidence is available, but where evidence is lacking or weak, wisdom should help. The problem, however, is that evidence, like law, involves interpretation, and interpretations may diverge. Similarly, wisdom is not always wise and common sense is known to be uncommon. It will be difficult to prepare guidelines without scientific experts, but users should use them with critical judgement.
Another institutional paper in this issue of the Journal is a position study of the European Society of Hypertension on the polypill in cardiovascular prevention (pp. 1546–1553). The potential usefulness of the polypill, that is, a pill combining a number of drugs each aiming at correcting a different cardiovascular risk factor, has raised interest recently, particularly as a means to overcome the treatment barriers appropriately approached in the Latin American guidelines, but, as remarked in the ESH position paper, the challenge in front of us is to provide evidence that the polypill approach can actually reduce cardiovascular outcomes to a greater extent or, at least, to a lower cost than standard treatment strategies.
Another large group of studies in the current issue are focused on a wide range of aspects of blood vessel research. Altered contraction mechanisms in the aortic wall of spontaneously hypertensive rats have been investigated by Méndez-López et al. (pp. 1594–1608), who have identified an impaired calcium buffering capacity of partially depolarized mitochondria dysregulating capacity calcium entry as an important mechanism of the increased aortic contractility in spontaneously hypertensive rats. Three studies are dealing with diagnostic problems. Grillo et al. (pp. 1609–1617) show that measurement of cardio–femoral pulse wave velocity and of variables derived from the central pulse waveform analysis by carotid tonometry is not biased by the presence of local atherosclerotic plaques. Grillo's study is commented by de Buyzere and Rietzschel (pp. 1569–1572), who remark these new data are reassuring for the current use of conventional tonometry-based indices, but it remains to be investigated which stiffness-related indices are biased by a local plaque. Obeid et al. (pp. 1618–1625) provide a validation and an improvement in the accuracy of a simple method for measuring arterial stiffness, namely finger–toe pulse wave velocity, whereas Leone et al. (pp. 1626–1634), in a comparative study between transthoracic echocardiography and cardiac magnetic resonance conclude that transthoracic echocardiography can be a reliable tool to assess proximal aorta diameters in hypertensive patients.
Three studies focus on the retinal microvasculature. Ponto et al. (pp. 1635–1645), using fundus photographs from 4309 participants in the Gutenberg Health Study in Germany, analyzed by the retinal vessels analyzer software IMEDOS, provide sex and age-specific normative data for retinal vasculature and find that persons with untreated or insufficiently treated hypertension are more likely to have retinal vessel equivalents outside the reference range. In an accompanying editorial commentary, Houben et al. (pp. 1573–1574) remark Ponto et al.'s data have an immediate clinical impact, particularly for comparing different clinical studies. However, to use these techniques for individual risk stratification and evaluation of treatment efficacy, additional technical improvements and standardization are required.
In two cross-sectional studies of adult participants of European descent, Kirin et al. (pp. 1646–1659) have examined factors influencing retinal vasculature, with the aim of estimating the extent and specificity of genetic contributions to each retinal vasculature feature. Muiesan et al. (pp. 1660–1665) describe a new small smartphone device (D-eye) usable in an emergency department setting for funduscopic examination, and report it can detect a significant number of fundus oculi abnormalities.
As usual, a number of other aspects of hypertension are covered in this issue of the Journal. Four studies deal with problems of blood pressure (BP) measurement. J.G. Wang et al. (pp. 1554–1563) review a hot topic of hypertension research, namely, the current evidence on the role of morning BP in the management of hypertension, and conclude there is some evidence it may contribute to the incidence of cardiovascular complications, but further research is needed before its usefulness in the management of hypertension can be considered proved. Xiao et al. (pp. 1577–1585) describe a new method for estimating aortic SBP by the use of radial SBP, DBP, and heart rate (HR) using artificial neural networks without recurring to peripheral waveform analysis. The pathophysiological significance of exaggerated BP response to graded exercise has been studied by Currie et al. (pp. 1586–1593) in endurance-trained athletes, and found not to be associated with the resting dysfunction of the sympathetic and cardiovascular systems observed in untrained individuals with exaggerated BP response. Sarak et al. (pp. 1709–1716) have investigated the optimal timing of BP measurement in patients undergoing haemodialysis by assessing which measurement change best correlates with changes in left ventricular mass index over 1 year, and report the change in initiation mean arterial pressure correlates best with the change in left ventricular mass.
Three studies are focused on aspects of baroreflex function and sympathetic control. Pinna et al. (pp. 1666–1675) have compared the predictive value of a number of representative indices of spontaneous baroreflex sensitivity in patients with heart failure, and conclude different indices have different predictive value. Zhang et al. (pp. 1676–1684) have evaluated the BP lowering efficacy of noninvasive magnetic stimulation of carotid sinus in rabbits and found it can lower BP, concluding this preliminary investigation warrants further study to establish the efficacy of this noninvasive strategy in treating refractory hypertension in men. Quarti Trevano et al. (pp. 1685–1690) have investigated to what extent HR reflects the sympathetic overactivity known to be associated with the metabolic syndrome and report HR can be regarded as a marker of cardiac adrenergic overdrive, but reliability as sympathetic marker is limited.
Finally, two studies have investigated problems of primary aldosteronism. Rossi et al. (pp. 1691–1697) have surveyed the number of patients discharged from hospitals in an Italian region (Emilia-Romagna) during 16 years, as well as the number of patients who underwent adrenalectomy. They found only 992 discharges and 160 adrenalectomies, corresponding to 1.9% and, respectively, 1% of cases expected according to the authors’ hypothesis of a 5% prevalence of primary aldosteronism among patients with hypertension. The authors’ conclusion is that primary aldosteronism is largely underdiagnosed and undertreated. Wu et al. (pp. 1698–1708) identified 2367 patients with primary aldosteronism from a 23-million population insurance registry in Taiwan, and matched them with a larger group of patients with essential hypertension. They report that during the course of 5.2 years primary aldosteronism patients who underwent adrenalectomy had a lower risk of new onset diabetes and all-cause mortality than matched essential hypertensive controls. The authors conclude in favour of an association of primary aldosteronism with a higher risk of metabolic syndrome and long-term mortality. In an accompanying commentary, Hitomi and Nishiyama (pp. 1575–1576) suggest a prospective randomized clinical trial should investigate the protective effects of adrenalectomy against new diabetes and mortality in primary aldosteronism.
Conflicts of interest
There are no conflicts of interest.