Aletta E Schutte

A call to action and a lifecourse strategy to address the global burden of raised blood pressure on current and future generations: the Lancet Commission on hypertension

Elevated blood pressure is the strongest modifiable risk factor for cardiovascular disease worldwide. Despite extensive knowledge about ways to prevent as well as to treat hypertension, the global incidence and prevalence of hypertension and, more importantly, its cardiovascular complications are not reduced—partly because of inadequacies in prevention, diagnosis, and control of the disorder in an ageing world. The aim of the Lancet Commission on hypertension is to identify key actions to improve the management of blood pressure both at the population and the individual level, and to generate a campaign to adopt the suggested actions at national levels to reduce the impact of elevated blood pressure globally. The first task of the Commission is this report, which briefly reviews the available evidence for prevention, identification, and treatment of elevated blood pressure, hypertension, and its cardiovascular complications. The report focuses on how as-yet unsolved issues might be tackled using approaches with population-wide impact and new methods for patient evaluation and education in the broadest sense (some of which are not always strictly evidence based) to manage blood pressure worldwide. The report is built around the concept of lifetime risk applicable to the entire population from conception. Development of subclinical and sometimes clinical cardiovascular disease results from lifetime exposure to cardiovascular risk factors combined with the susceptibility of individuals to the harmful consequences of these risk factors. The Commission recognises the importance of other cardiovascular risk factors—eg, smoking, obesity, dyslipidaemia, and diabetes mellitus—on antihypertensive treatment. However, as a Commission on hypertension, this report focuses mainly on issues and actions related to elevated blood pressure. Previous action plans for improving management of elevated blood pressure and hypertension have not yet provided adequate results. Therefore, the Commission has identified ten essential and achievable goals and ten accompanying, mutually additive, and synergistic key actions that—if implemented effectively and broadly—will make substantial contributions to the management of blood pressure globally. The Commission deliberately has not listed these complementary key actions by priority because the balance between strength of evidence, feasibility, and potential benefit could differ by country.

Comparison of central pressure estimates obtained from SphygmoCor, Omron HEM-9000AI and carotid applanation tonometry

Background The Omron HEM-9000AI is the first automated tonometer to provide an estimate of central SBP (cSBP), which is considered to be more predictive of cardiovascular events than brachial pressure. However, considerable differences between the cSBP estimate of Omron and that of SphygmoCor have been reported, but not explained. This study assesses the sources of differences between both cSBP estimates and provides a handle on which estimate is closest to reality. Method For this purpose, aortic cSBP derived from calibrated carotid SBP was used as device- and algorithm-independent reference. Radial, brachial and carotid applanation tonometry were performed in 143 black South Africans, aged 39–91 years. Each individual was measured with an Omron HEM-9000AI and a SphygmoCor. Results When using both devices as advocated by their manufacturers, the corresponding cSBP estimates correlated strongly (r = 0.99, P < 0.001), but the Omron estimate was 18.8 (4.3) mmHg higher than the SphygmoCor estimate. Aortic SBP was in between both estimates: 11.7 (5.5) mmHg lower than cSBP-Omron and 7.1 (5.0) mmHg higher than cSBP-SphygmoCor. Alternative calibration of the radial SphygmoCor-curves with radial instead of brachial pressures yielded a cSBP that was 3.0 (4.2) mmHg lower than aortic SBP. The shape of the recorded pressure waves was similar in both devices: less than 5% of the observed cSBP difference was caused by differences in wave shape. Conclusion The results from this study demonstrate that the considerable difference between the central pressure estimates of Omron HEM-9000AI and SphygmoCor is due to algorithm differences, and suggest that the overestimation by Omron HEM-9000AI is larger than the underestimation by SphygmoCor.

Monitoring the South African population’s salt intake: spot urine v. 24 h urine

OBJECTIVEnThe present study set out to determine whether morning spot urine samples can be used to monitor Na (and K) intake levels in South Africa, instead of the gold standard 24 h urine sample.nnnDESIGNnParticipants collected one 24 h and one spot urine sample for Na and K analysis, after which estimations using three different formulas (Kawasaki, Tanaka and INTERSALT) were calculated.nnnSETTINGnBetween 2013 and 2015, urine samples were collected from different population groups in South Africa.nnnSUBJECTSnA total of 681 spot and 24 h urine samples were collected from white (n 259), black (n 315) and Indian (n 107) subgroups, mostly women.nnnRESULTSnThe Kawasaki and the Tanaka formulas showed significantly higher (P≤0·001) estimated Na values than the measured 24 h excretion in the whole population (5677·79 and 4235·05 v. 3279·19 mg/d). The INTERSALT formula did not differ from the measured 24 h excretion for the whole population. The Kawasaki formula seemed to overestimate Na excretion in all subgroups tested and also showed the highest degree of bias (-2242 mg/d, 95 % CI-10 659, 6175) compared with the INTERSALT formula, which had the lowest bias (161 mg/d, 95 % CI-4038, 4360).nnnCONCLUSIONSnEstimations of Na excretion by the three formulas should be used with caution when reporting on Na intake levels. More research is needed to validate and develop a specific formula for the South African context with its different population groups. The WHOs recommendation of using 24 h urine collection until more studies are carried out is still supported.

Morning blood pressure surge in young black and white adults: The African-PREDICT Study

An exaggerated morning blood pressure surge (MBPS) has independent predictive value for cardiovascular mortality and is suggested to be prevalent in elderly hypertensive patients: men and white populations. To better understand the MBPS profile in a young and normotensive population, we evaluated the MBPS in young adults and explored associations with demographic, cardiovascular and health behaviour measurements. We included 845 black (nu2009=u2009439) and white (nu2009=u2009406) men and women aged between 20 and 30 years. We calculated the sleep-trough and dynamic morning surge, and compared demographic data, health behaviours and ambulatory blood pressure according to MBPS quartiles. In the total group, higher waist circumference, socioeconomic score, lean mass, ambulatory blood pressure (24-h, daytime blood pressure) and increased night-time dipping (all pu2009<u20090.05) were found in the highest sleep-trough and dynamic morning surge quartiles. In the total white group, particularly men, both sleep-trough and dynamic morning surge were higher than the black group (all pu2009<u20090.013). More black participants were non-dippers than whites (44% vs 34%; pu2009=u20090.004). In multivariable adjusted regression in the total group, we found no consistent associations of MBPS with demographic and health behaviour measurements. MBPS related independently and positively with night-time percentage dipping in all ethnic groups (all pu2009<u20090.01). Ethnic differences in MBPS is evident in young adults, with a higher, but normal MBPS in white men. A non-dipping night-time pattern in young black adults (with reduced MBPS) and a higher MBPS (observed in dippers) may serve as potential risk factors for cardiovascular disease.

Are the American Heart Association/American College of Cardiology High Blood Pressure Guidelines Fit for Global Purpose?: Thoughts From the International Society of Hypertension

In 2017, the American College of Cardiology (ACC), the American Heart Association (AHA), and 9 other American societies released guidelines for the prevention, detection, evaluation, and management of high blood pressure (BP) in adults.1nnThese guidelines are perhaps the most controversial set of US guidelines—even more so than those attributed to some of the committee set up to produce the guidelines of the Eighth Joint National Committee in 2014.2nnBefore discussing the various controversial aspects of the ACC/AHA guidelines, the International Society of Hypertension would like to congratulate the authors on 3 counts. First, emphasis was placed on the appropriate technique of BP measurements and the increased need for out-of-office BP measurement. Second, the value of risk assessment was recognized and introduced for the first time in US guidelines and finally, perhaps in part because of the controversial nature of the document, awareness of the importance of BP as a global cause of morbidity and mortality has been raised.nnThe central controversy around which several others arise is the redefining of hypertension—as a systolic BP ≥130 mmu2009Hg or a diastolic BP ≥80 mmu2009Hg. Although there is a clear dose-response relationship between increasing BP levels and adverse cardiovascular outcomes,3 this preempts the ability, based on predicting cardiovascular events, of precisely defining hypertension. However, the pragmatic definition proposed by Geoffrey Rose decades ago should perhaps be considered—viz: “that level of BP above which investigation and management does more good than harm.”4 Does the new BP level proposed in the ACC/AHA guidelines fully satisfy that criterion? Perhaps not. To date, the relevant data are inconsistent and hence controversial.nnThe problem arises because the definition of hypertension, treatment thresholds, and BP targets should …

HIV treatment is associated with a twofold higher probability of raised triglycerides: Pooled analyses in 21 023 individuals in sub-Saharan Africa

Background Anti-retroviral therapy (ART) regimes for HIV are associated with raised levels of circulating triglycerides (TGs) in western populations. However, there are limited data on the impact of ART on cardiometabolic risk in sub-Saharan African (SSA) populations. Methods Pooled analyses of 14 studies comprising 21 023 individuals, on whom relevant cardiometabolic risk factors (including TG), HIV and ART status were assessed between 2003 and 2014, in SSA. The association between ART and raised TG (>2.3 mmol/L) was analysed using regression models. Findings Among 10 615 individuals, ART was associated with a two-fold higher probability of raised TG (RR 2.05, 95% CI 1.51–2.77, I2 = 45.2%). The associations between ART and raised blood pressure, glucose, HbA1c, and other lipids were inconsistent across studies. Interpretation Evidence from this study confirms the association of ART with raised TG in SSA populations. Given the possible causal effect of raised TG on cardiovascular disease (CVD), the evidence highlights the need for prospective studies to clarify the impact of long term ART on CVD outcomes in SSA.

What are the financial implications of the 2017 AHA/ACC High Blood Pressure Guideline?

Since the publication of the 2017 High Blood Pressure Guideline from the American College of Cardiology (ACC) and the American Heart Association (AHA), commentaries have been published debating medical perspectives on the usefulness, appropriateness, feasibility and scientific nature thereof. The critical point that most are deliberating on is the implementation of a new definition for hypertension. It was almost 25 years ago that the cut-offs for Stage 1 Hypertension were changed from 160/90mmHg to 140/90mmHg. In 2017 the AHA/ACC Guideline once again moved away from the globally accepted cut-offs, defining Stage 1 Hypertension based on the lower thresholds of 130–139/80–89mmHg. Whilst it is important to reflect on the scientific grounds of these guidelines, as well as the feasibility thereof, it is the financial implications that would eventually result in governments adopting the guidelines. Cardiovascular diseases clearly represent a major economic burden on health care systems, and with hypertension being the most important contributor, targeting better prevention, treatment and control makes sense. The concept of early treatment is also aligned with the lifecourse approach proposed by the Lancet Commission of Hypertension. An important next step for health economists is to establish whether the new AHA/ACC Guideline will result in improvement of direct cost reduction in terms of health care systems (such as fewer events, hospitalisations, rehabilitation services, physician visits), as well as indirect costs associated with morbidity and mortality (such as loss in productivity and disabilities). With findings from the SPRINT trial embedded in the AHA/ACC Guidelines, cost-effectiveness analysis from SPRINT is important. The SPRINT Research Group thus performed this analysis (in adults at high risk for cardiovascular disease), and found that intensive blood pressure (BP) control was cost-effective and below common willingness-to-pay thresholds in the United States. A similar study modelling a cost-effective analysis of lifetime benefits and costs among 68-year-old high-risk adults with hypertension, but not diabetes, also confirmed that intensive BP management provides ‘excellent value’. The authors further stated that it remains cost-effective even with substantially higher adverse event rates. An economic analysis by the PAST-BP study in England evaluated the cost-effectiveness of a systolic BP target of <130mmHg in people with a history of stroke or transient ischaemic attacks. Findings again confirmed that intensive systolic pressure lowering is cost-effective in those with a history of stroke, although they pointed out that it was difficult to tease out whether this benefit was due to the lower BP target, or due to more active BP management. Collectively these studies, which were performed in high income countries, clearly point to costeffectiveness of the lower BP thresholds. However, it seems that the feasibility of implementing the targets remains at the core of the debate. The adoption of the new AHA/ACC Guideline in the rest of the world therefore remains controversial. This may be due to weaker health systems in lowand middle-income countries, where the burden of hypertension is the greatest, and hypertension management at the current 140/ 90mmHg targets remains inadequate. These realities have spurred several new approaches to improve hypertension management, such as the introduction of selfmanagement and the polypill, which have the potential to be cost-effective. Where the abovementioned analyses focus on the overall and long-term effects of the new AHA/ACC Guidelines, the immediate consequence is that more patients will qualify for antihypertensive medication. For the United States this increase was reportedly a minor increase when moving from the Seventh Report of the Joint National Committee on Prevention,