Efficacy of different drug classes used to initiate antihypertensive treatment in black subjects: results of a randomized trial in Johannesburg, South Africa

Update of the clinical guideline for hypertension diagnosis and treatment in Iran

BACKGROUND

This article introduces the updated version of the Iranian guideline for the diagnosis and treatment of hypertension in adults. The initial version of the national guideline was developed in 2011 and updated in 2014. Among the reasons necessitating the update of this guideline were the passage of time, the incompleteness of the scopes, the limitation of the target group, and more important is the request of the ministry of health in Iran.

METHOD

The members of the guideline updating group, after reviewing the original version and the new evidence, prepared 10 clinical questions regarding hypertension, and based on the evidence found from the latest scientific documents, provided recommendations or suggestions to answer these questions.

RESULT

According to the updated guideline, the threshold for office prehypertension diagnosis should be considered the systolic blood pressure (SBP) of 130-139 mmHg and/or the diastolic blood pressure (DBP) of 80-89 mmHg, and in adults under 75 years of age without comorbidities, the threshold for office hypertension diagnosis should be SBP ≥ 140 mmHg and or DBP ≥ 90 mmHg. The goal of treatment in adults who lack comorbidities and risk factors is SBP < 140 mmHg and DBP < 90 mmHg. The first-line treatment recommended in people with prehypertension is lifestyle modification, while for those with hypertension, pharmacotherapy along with lifestyle modification. The threshold to start drug therapy is determined at SBP ≥ 140 mmHg and or DBP ≥ 90 mmHg, and the first-line treatment is considered a drug or a combined pill of antihypertensive drugs, including ACEIs, ARBs, thiazide and thiazide-like agents, or CCBs. At the beginning of the pharmacotherapy, the Guideline Updating Group members suggested studying serum electrolytes, creatinine, lipid profile, fasting sugar, urinalysis, and an electrocardiogram. Regarding the visit intervals, monthly visits are suggested at the beginning of the treatment or in case of any change in the type or dosage of the drug until achieving the treatment goal, followed by every 3-to-6-month visits. Moreover, to reduce further complications, it was suggested that healthcare unit employees use telehealth strategies.

CONCLUSIONS

In this guideline, specific recommendations and suggestions have been presented for adults and subgroups like older people or those with cardiovascular disease, diabetes mellitus, chronic kidney disease, and COVID-19.

Role of atrial natriuretic peptide in the dissociation between flow relations with ventricular mass and function in a community with volume-dependent hypertension

Background

Whether differential effects of volume load on left ventricular mass (LVM) and function occur in sustained volume-dependent primary hypertension, and the impact of atrial natriuretic peptide (ANP) on these effects, is unknown.

Methods

From aortic pressure, velocity and diameter measurements and echocardiography, we determined in an African community (n = 772), the impact of systemic flow-induced increases in central pulse pressure (PPc) and circulating ANP (ELISA) on LVM and indexes of function.

Results

Stroke volume (SV), but not aortic flow (Q), was associated with LVM and mean wall thickness (MWT) beyond stroke work and confounders (p < 0.0001). Adjustments for SV markedly decreased the relationships between PPc and LVMI or MWT. However, neither SV, nor Q were independently associated with either myocardial s', e', or E/e' (p > 0.14) and adjustments for neither SV nor Q modified relationships between PPc and s', e' or E/e' (p < 0.005 to <0.0001). SV was nevertheless strongly and independently associated with ANP (p < 0.0001) and ANP was similarly strikingly associated with s' (p < 0.0001) and e' (p < 0.0005), but not E/e', independent of confounders and several determinants of afterload. Importantly, ANP concentrations were inversely rather than positively associated with LV diastolic dysfunction (DD) (p < 0.005) and lower rather than higher ANP concentrations contributed markedly to the ability to detect DD in those with, but not without LV hypertrophy.

Conclusion

In populations with sustained volume-dependent hypertension, flow (SV)-related increases in PP have a major impact on LV structure, but not on function, an effect attributed to parallel striking beneficial actions of ANP on myocardial function.

Real-World Effectiveness and Safety of Two-Drug Single Pill Combinations of Antihypertensive Medications for Blood Pressure Management: A Follow-Up on Daily Cardiology Practice in Douala, Cameroon

INTRODUCTION

Hypertension is the leading cause of morbidity and mortality in sub-Saharan Africa (SSA). Current guidelines recommend using two or more antihypertensive agents in single pill combinations (SPCs) to treat hypertension, but data from African patients that support these recommendations are lacking. We assessed the effectiveness and tolerance of three SPCs in lowering blood pressure (BP) amongst hypertensive patients in Douala.

METHOD

All patients included in the hypertension registry of the Douala General Hospital and the Douala Cardiovascular Center between January 2010 and May 2020, and receiving a two-drug SPCs (renin-angiotensin system inhibitors (RAASi) + diuretics (DIU), calcium channel blockers (CCB) + RAASi, or DIU + CCB) were tracked from baseline through 16 weeks. Our primary outcome was a decrease in systolic BP (SBP) from baseline up to 16 weeks after initiation of treatment. A mixed linear repeated model was used to evaluate the change of SBP from baseline to week 16, while controlling for age, gender, and baseline SBP. Statistical significance was set at p < 0.05.

RESULTS

Of 377 participants on two-drug SPCs, 123 were on CCB + DIU, 96 on RAASi + CCB, and 158 on RAASi + DIU. The mean age was 54.6 (± 11.2) years. At baseline, participants on RAASi + CCB presented with slightly higher SBP compared to the other two groups. Overall, the SBP decreased by 34.3 (± 14.2) mmHg from baseline values and this was comparable across the three groups of SPCs (p = 0.118). The control rate after 16 weeks of follow-up was 62.3% with no significant difference between groups. The occurrence of adverse events was 3.4% and was comparable among the three groups.

CONCLUSION

The three two-drug SPCs were highly effective in reducing and controlling BP with low and similar rates of adverse effects. Long-term data documenting safety and whether these agents exert a differential cardiovascular effect in addition to and independent of their BP-lowering effect are needed for SSA populations.

Personalized hypertension treatment recommendations by a data-driven model

BACKGROUND

Hypertension is a prevalent cardiovascular disease with severe longer-term implications. Conventional management based on clinical guidelines does not facilitate personalized treatment that accounts for a richer set of patient characteristics.

METHODS

Records from 1/1/2012 to 1/1/2020 at the Boston Medical Center were used, selecting patients with either a hypertension diagnosis or meeting diagnostic criteria (≥ 130 mmHg systolic or ≥ 90 mmHg diastolic, n = 42,752). Models were developed to recommend a class of antihypertensive medications for each patient based on their characteristics. Regression immunized against outliers was combined with a nearest neighbor approach to associate with each patient an affinity group of other patients. This group was then used to make predictions of future Systolic Blood Pressure (SBP) under each prescription type. For each patient, we leveraged these predictions to select the class of medication that minimized their future predicted SBP.

RESULTS

The proposed model, built with a distributionally robust learning procedure, leads to a reduction of 14.28 mmHg in SBP, on average. This reduction is 70.30% larger than the reduction achieved by the standard-of-care and 7.08% better than the corresponding reduction achieved by the 2nd best model which uses ordinary least squares regression. All derived models outperform following the previous prescription or the current ground truth prescription in the record. We randomly sampled and manually reviewed 350 patient records; 87.71% of these model-generated prescription recommendations passed a sanity check by clinicians.

CONCLUSION

Our data-driven approach for personalized hypertension treatment yielded significant improvement compared to the standard-of-care. The model implied potential benefits of computationally deprescribing and can support situations with clinical equipoise.

Attenuated Relationships Between Indexes of Volume Overload and Atrial Natriuretic Peptide in Uncontrolled, Sustained Volume-Dependent Primary Hypertension

BACKGROUND

Whether systolic blood pressure (SBP) control in sustained volume-dependent primary hypertension is associated with blunted ANP (atrial natriuretic peptide) relationships with indexes of volume load is unknown.

METHODS

Systemic hemodynamics (central pressure, echocardiographic aortic velocity and diameter measurements in the outflow tract), circulating ANP concentrations (ELISA assays) and glomerular and tubular function (24-hour urine collections [n=519]) were determined in a community of African ancestry (n=772).

RESULTS

As compared with those with a controlled SBP, those with an uncontrolled SBP (n=198) showed lower ANP concentrations (P<0.005) despite higher stroke volume and cardiac output (P<0.0001) and renal differences consistent with enhanced fluid retention. In those with a controlled SBP, fractional Na⁺ excretion (FeNa⁺; P<0.0005) and creatinine clearance (glomerular filtration rate; P<0.005) were inversely associated with ANP concentrations independent of confounders. Moreover, in those with a controlled SBP, stroke volume and cardiac output (P<0.0001) were independently and positively associated with ANP concentrations. In addition, in those with a controlled SBP, ANP concentrations were independently and inversely associated with systemic vascular resistance (SVR; P<0.0001) and aortic characteristic impedance (Zc; P<0.005). By contrast, in those with uncontrolled SBP, no relationships between either stroke volume (P>0.25), cardiac output (P>0.29), FeNa⁺ (P>0.77), or glomerular filtration rate (P>0.47) and ANP concentrations were noted. Furthermore, in those with an uncontrolled SBP, no relationships between ANP concentrations and SVR or Zc were observed (P>0.34).

CONCLUSIONS

In a population where primary hypertension is strongly volume-dependent, those with an uncontrolled SBP have an attenuated relationship between ANP and both renal and hemodynamic indexes of volume overload and the vascular effects of ANP.

Comparison between the world health organization (WHO) and international society of hypertension (ISH) guidelines for hypertension

The global burden of hypertension remains an unsolved problem, especially in low- and middle-income countries (LMICs). For this reason, clinical practice guidelines containing the latest evidence-based recommendations are crucial in the management of hypertension. It is noteworthy that guidelines simply translated from those of high-income countries (HICs) are not the solution to the problem of hypertension in LMICs. Among the numerous guidelines available, those of the World Health Organisation and the International Society of Hypertension are the latest to be published as of the writing of this article. In this review, we conducted both general and specific comparisons between the recommendations supplied by both guidelines. Differences in aspects of hypertension management such as the timing of antihypertensive initiation, assessment of comorbidities and cardiovascular risk factors, pharmacological therapy selection, and blood pressure target and reassessment are explored. Lastly, the implications of the differences found between the two guidelines in both LMICs and HICs are discussed.Key messagesCurrently, with low treatment and control rates, hypertension remains a burden in low- and middle-income countries (LMICs).The lack of customised guidelines for LMICs cannot be solved simply by adopting guidelines from high-income countries.The World Health Organisation (WHO) recently published a clinical guideline for the pharmacological management of hypertension in LMICs. We compare select recommendations from the guidelines to those published by the International Society of Hypertension.

Independent relationships between renal mechanisms and systemic flow, but not resistance to flow in primary hypertension in Africa

AIMS

Whether renal mechanisms of hypertension primarily translate into increases in systemic vascular resistance (SVR) in all populations is uncertain. We determined whether renal mechanisms associate with either increases in SVR (and impedance to flow) or systemic flow in a community of African ancestry.

METHOD

In a South African community sampled across the full adult age range (n = 546), we assessed stroke volume (SV), peak aortic flow (Q), SVR, characteristic impedance (Zc) and total arterial compliance (TAC) from velocity and diameter measurements in the outflow tract (echocardiography) and central arterial pressures. Renal changes were determined from creatinine clearance (glomerular filtration rate, GFR) and fractional Na+ excretion (FeNa+) (derived from 24-h urine collections).

RESULTS

Independent of confounders (including MAP and pressures generated by the product of Q and Zc), SV (and hence cardiac output) (P < 0.0001) and Q (P < 0.01), but not SVR, Zc or TAC (P = 0.09-0.20) were independently associated with decreases in both GFR (index of nephron number) and FeNa+. Through an interactive effect (P < 0.0001), the impact of GFR on SV or Q was strongly determined by FeNa+ and vice versa. The relationship between the GFR-FeNa+ interaction and either SV or Q was noted in those above or below 50 years of age, although neither GFR, FeNa+ nor the interaction were independently associated with SVR, Zc or TAC at any age.

CONCLUSION

Across the full adult lifespan, in groups of African ancestry, renal mechanisms of hypertension translate into increases in systemic flow rather than into resistance or impedance to flow.

Hemodynamic and Functional Correlates of Concentric vs. Eccentric LVH in a Community-Based Sample With Prevalent Volume-Dependent Hypertension

BACKGROUND

Whether in volume-dependent primary hypertension, concentric left ventricular (LV) remodeling beyond hypertrophy (LVH) represents the impact of a pressure rather than a volume overload, is unclear.

METHODS

Using central arterial pressure, and aortic velocity and diameter measurements in the outflow tract (echocardiography), we determined the factors that associate with concentric LVH or remodeling in a community of African ancestry (n = 709) with prevalent volume-dependent primary hypertension.

RESULTS

Both left ventricular mass index (LVMI) and relative wall thickness (RWT) were positively and independently associated with end diastolic volume (EDV), stroke volume (SV), and peak aortic flow (Q) (P < 0.05 to <0.0001). However, neither LVMI nor RWT were positively and independently associated with systemic vascular resistance (SVR), or aortic characteristic impedance (Zc) or inversely associated with total arterial compliance (TAC). Consequently, both concentric (P < 0.0001) and eccentric (P < 0.0001) LVH were associated with similar increases in EDV, SV, and either office brachial, central arterial, or 24-hour blood pressures (BP), but neither increases in SVR or Zc nor decreases in TAC. LV RWT, but not LVMI was nevertheless independently and inversely associated with myocardial systolic function (midwall shortening and s') (P < 0.05 to <0.005) and decreases in LV systolic function were noted in concentric (P < 0.05), but not eccentric LVH.

CONCLUSIONS

In volume-dependent primary hypertension, concentric LVH is determined as much by volume-dependent increases in systemic flow and an enhanced BP as eccentric LVH. Concentric remodeling nevertheless reflects decreases in systolic function beyond LVH.

The coArtHA trial-identifying the most effective treatment strategies to control arterial hypertension in sub-Saharan Africa: study protocol for a randomized controlled trial

BACKGROUND

Arterial hypertension is the most prevalent risk factor for cardiovascular disease in sub-Saharan Africa. Only a few and mostly small randomized trials have studied antihypertensive treatments in people of African descent living in sub-Saharan Africa.

METHODS

In this open-label, three-arm, parallel randomized controlled trial conducted at two rural hospitals in Lesotho and Tanzania, we compare the efficacy and cost-effectiveness of three antihypertensive treatment strategies among participants aged ≥ 18 years. The study includes patients with untreated uncomplicated arterial hypertension diagnosed by a standardized office blood pressure ≥ 140/90 mmHg. The trial encompasses a superiority comparison between a triple low-dose antihypertensive drug combination versus the current standard of care (monotherapy followed by dual treatment), as well as a non-inferiority comparison for a dual drug combination versus standard of care with optional dose titration after 4 and 8 weeks for participants not reaching the target blood pressure. The sample size is 1268 participants with parallel allocation and a randomization ratio of 2:1:2 for the dual, triple and control arms, respectively. The primary endpoint is the proportion of participants reaching a target blood pressure at 12 weeks of ≤ 130/80 mmHg and ≤ 140/90 mmHg among those aged < 65 years and ≥ 65 years, respectively. Clinical manifestations of end-organ damage and cost-effectiveness at 6 months are secondary endpoints.

DISCUSSION

This trial will help to identify the most effective and cost-effective treatment strategies for uncomplicated arterial hypertension among people of African descent living in rural sub-Saharan Africa and inform future clinical guidelines on antihypertensive management in the region.

TRIAL REGISTRATION

Clinicaltrials.gov NCT04129840 . Registered on 17 October 2019 ( https://www.clinicaltrials.gov/ ).

Contribution of systemic blood flow to untreated or inadequately controlled systolic--diastolic or isolated systolic hypertension in a community sample of African ancestry

AIMS

Age-related increases in systemic blood flow [stroke volume (SV), cardiac output (CO), and aortic flow (Q)] contribute substantially to untreated or inadequately controlled (uncontrolled) blood pressure (BP) in Africa. We aimed to identify the haemodynamic determinants of uncontrolled systolic--diastolic (Syst--diast HT) versus uncontrolled isolated systolic (ISH) or diastolic (IDH) hypertension.

METHODS

Using central arterial pressure and aortic outflow tract velocity and diameter measurements (echocardiography), the haemodynamic correlates of BP were determined in 725 community participants of African ancestry (19.6% uncontrolled Syst--diast HT, 9.2% uncontrolled ISH, 11.3% uncontrolled IDH).

RESULTS

Independent of confounders, compared with those with a normotensive BP, those with uncontrolled Syst--diast HT had increases in SV, CO, Q, systemic vascular resistance (SVR) and aortic characteristic impedance (Zc) and decreases in total arterial compliance (TAC) (P < 0.05--P < 0.0001). In multivariate regression models, uncontrolled Syst--diast HT was as strongly associated with Q, SV or CO as with SVR (P = 0.04--P = 0.20), Zc (P = 0.74--P < 0.0005) and TAC (P = 0.43--P < 0.005). Independent of confounders, compared with normotensive individuals those with uncontrolled ISH had increases in SV, CO, Q and Zc but not SVR, and decreases in TAC (P < 0.05-P < 0.0001), and those with IDH only had increases in SVR (P < 0.0001). Uncontrolled ISH was more strongly associated with Q, SV and CO than with SVR (P < 0.0005), but less than with TAC (P < 0.05--P < 0.0005).

CONCLUSION

In groups of African ancestry living in Africa, hypertension because of increases in either SBP or DBP is as strongly associated with increases in systemic flow (SV, Q) as with arterial and arteriolar effects (Zc, TAC, SVR).

Distinct Contribution of Systemic Blood Flow to Hypertension in an African Population Across the Adult Lifespan

Although hypertension in groups of African ancestry is volume-dependent, the relative impact of systemic flow (stroke volume, peak aortic flow [Q]) versus vascular mechanisms (systemic vascular resistance, aortic characteristic impedance [Zc], total arterial compliance) components of arterial load has not been evaluated across the adult age range. In participants of African ancestry (n=824, age=16–99 years, 68.3% female), using central arterial pressure and aortic velocity and diameter measurements in the outflow tract, we determined the hemodynamic correlates of age-related increases in blood pressure. Strong independent positive relations between age and stroke volume or peak aortic Q were noted ( P <0.0001), effects associated with ventricular end diastolic volume and aldosterone-to-renin ratios. Age-related increases in mean arterial pressure were associated with stroke volume and not systemic vascular resistance. Although age-Q relations began from early adulthood, initially an inverse association between age and aortic Zc ( P <0.0001) driven by increments in aortic root diameter ( P <0.0001) prevented an enhanced systolic blood pressure and pulse pressure. When Zc began to positively relate to age ( P <0.0001), age-Q relations translated into increases in forward wave pressures and hence systolic blood pressure and pulse pressure. Age relations with pulse pressure were as strongly determined by Q as by Zc or total arterial compliance (0.027±0.001 versus 0.028±0.001 and 0.032±0.003 mm Hg per yearly increase in pulse pressure produced by Q, Zc, and total arterial compliance; P <0.0001). Uncontrolled hypertension (confirmed with 24-hour blood pressure) was determined more by Q, Zc, and total arterial compliance than by increases in systemic vascular resistance ( P <0.0005 for comparison). In conclusion, relationships between age and systemic blood flow contribute markedly to hypertension in groups of African origins.

Pharmacotherapy for hypertension in Sub-Saharan Africa: a systematic review and network meta-analysis

BACKGROUND

The highest burden of hypertension is found in Sub-Saharan Africa (SSA) with a threefold greater mortality from stroke and other associated diseases. Ethnicity is known to influence the response to antihypertensives, especially in black populations living in North America and Europe. We sought to outline the impact of all commonly used pharmacological agents on both blood pressure reduction and cardiovascular morbidity and mortality in SSA.

METHODS

We used similar criteria to previous large meta-analyses of blood pressure agents but restricted results to populations in SSA. Quality of evidence was assessed using a risk of bias tool. Network meta-analysis with random effects was used to compare the effects across interventions and meta-regression to explore participant heterogeneity.

RESULTS

Thirty-two studies of 2860 participants were identified. Most were small studies from single, urban centres. Compared with placebo, any pharmacotherapy lowered SBP/DBP by 8.51/8.04 mmHg, and calcium channel blockers (CCBs) were the most efficacious first-line agent with 18.46/11.6 mmHg reduction. Fewer studies assessing combination therapy were available, but there was a trend towards superiority for CCBs plus ACE inhibitors or diuretics compared to other combinations. No studies examined the effect of antihypertensive therapy on morbidity or mortality outcomes.

CONCLUSION

Evidence broadly supports current guidelines and provides a clear rationale for promoting CCBs as first-line agents and early initiation of combination therapy. However, there is a clear requirement for more evidence to provide a nuanced understanding of stroke and other cardiovascular disease prevention amongst diverse populations on the continent.

TRIAL REGISTRATION

PROSPERO, CRD42019122490. This review was registered in January 2019.

Comparison of Dual Therapies for Lowering Blood Pressure in Black Africans

BACKGROUND

The prevalence of hypertension among black African patients is high, and these patients usually need two or more medications for blood-pressure control. However, the most effective two-drug combination that is currently available for blood-pressure control in these patients has not been established.

METHODS

In this randomized, single-blind, three-group trial conducted in six countries in sub-Saharan Africa, we randomly assigned 728 black patients with uncontrolled hypertension (≥140/90 mm Hg while the patient was not being treated or was taking only one antihypertensive drug) to receive a daily regimen of 5 mg of amlodipine plus 12.5 mg of hydrochlorothiazide, 5 mg of amlodipine plus 4 mg of perindopril, or 4 mg of perindopril plus 12.5 mg of hydrochlorothiazide for 2 months. Doses were then doubled (10 and 25 mg, 10 and 8 mg, and 8 and 25 mg, respectively) for an additional 4 months. The primary end point was the change in the 24-hour ambulatory systolic blood pressure between baseline and 6 months.

RESULTS

The mean age of the patients was 51 years, and 63% were women. Among the 621 patients who underwent 24-hour blood-pressure monitoring at baseline and at 6 months, those receiving amlodipine plus hydrochlorothiazide and those receiving amlodipine plus perindopril had a lower 24-hour ambulatory systolic blood pressure than those receiving perindopril plus hydrochlorothiazide (between-group difference in the change from baseline, -3.14 mm Hg; 95% confidence interval [CI], -5.90 to -0.38; P = 0.03; and -3.00 mm Hg; 95% CI, -5.8 to -0.20; P = 0.04, respectively). The difference between the group receiving amlodipine plus hydrochlorothiazide and the group receiving amlodipine plus perindopril was -0.14 mm Hg (95% CI, -2.90 to 2.61; P=0.92). Similar differential effects on office and ambulatory diastolic blood pressures, along with blood-pressure control and response rates, were apparent among the three groups.

CONCLUSIONS

These findings suggest that in black patients in sub-Saharan Africa, amlodipine plus either hydrochlorothiazide or perindopril was more effective than perindopril plus hydrochlorothiazide at lowering blood pressure at 6 months. (Funded by GlaxoSmithKline Africa Noncommunicable Disease Open Lab; CREOLE ClinicalTrials.gov number, NCT02742467.).

Rationale and design of the comparison of 3 combination therapies in lowering blood pressure in black Africans (CREOLE study): 2 × 3 factorial randomized single-blind multicenter trial

BACKGROUND

Current hypertension guidelines recommend the use of combination therapy as first-line treatment or early in the management of hypertensive patients. Although there are many possible combinations of blood pressure(BP)-lowering therapies, the best combination for the black population is still a subject of debate because no large randomized controlled trials have been conducted in this group to compare the efficacy of different combination therapies to address this issue.

METHODS

The comparison of 3 combination therapies in lowering BP in the black Africans (CREOLE) study is a randomized single-blind trial that will compare the efficacy of amlodipine plus hydrochlorothiazide versus amlodipine plus perindopril and versus perindopril plus hydrochlorothiazide in blacks residing in sub-Saharan Africa (SSA). Seven hundred two patients aged 30-79 years with a sitting systolic BP of 140 mm Hg and above, and less than 160 mm Hg on antihypertensive monotherapy, or sitting systolic BP of 150 mm Hg and above, and less than 180 mm Hg on no treatment, will be centrally randomized into any of the 3 arms (234 into each arm). The CREOLE study is taking place in 10 sites in SSA, and the primary outcome measure is change in ambulatory systolic BP from baseline to 6 months. The first patient was randomized in June 2017, and the trial will be concluded by 2019.

CONCLUSIONS

The CREOLE trial will provide unique information as to the most efficacious 2-drug combination in blacks residing in SSA and thereby inform the development of clinical guidelines for the treatment of hypertension in this subregion.

Hypertension in Athletes and Active Populations

Hypertension continues to be the most common cardiovascular disorder in the USA and worldwide. While generally considered a disorder of aging individuals, hypertension is more prevalent in athletes and the active population than is generally appreciated. The timely detection, diagnosis, and appropriate treatment of hypertension in athletes must focus on both adequately managing the disorder and ensuring safe participation in sport while not compromising exercise capacity. This publication focuses on appropriately diagnosing hypertension, treating hypertension in the athletic population, and suggesting follow-up and participation guidelines for athletes.

Hypertension in Sub-Saharan Africa: A Contextual View of Patterns of Disease, Best Management, and Systems Issues

Sub-Saharan Africa (SSA) bears the highest burden of both communicable and noncommunicable disease and has the weakest health systems. Much attention is directed toward a rising burden of chronic disease in the setting of epidemiologic transition and urbanization. Indeed, the highest prevalence of hypertension globally is in the World Health Organization's African region at 46% of adults aged 25 and above. And while hypertension in SSA is common, its prevalence varies significantly between urban and rural settings. Although there is evidence for epidemiologic transition in urban areas, there is also evidence of static levels of hypertension within rural areas, which comprise more than 70% of the population of SSA. Furthermore, overall cardiovascular (CV) risk in rural areas remains low. The mean age of hypertensives in SSA is approximately 30s to 40s, burdening those at peak productivity. Complications of hypertension are frequent, given the poor levels of awareness and treatment (<10%) of hypertension on the continent. Such complications include primarily stroke and hypertensive heart disease, as ischemic heart disease is uncommon. Mortality associated with these complications is high, with in-hospital mortality from 2 different sites reported as around 20%. The overall burden of hypertension is likely to be more related to poor access and availability of health systems and is representative of a looming crisis in health care delivery. The best approaches to population-wide treatment are those that utilize CV risk prediction for those with stage 1 hypertension, whereas treatment is generally indicated for all those with stage 2 or greater hypertension, especially in light of the high burden of stroke in SSA. Current guidelines recommend first-line drug therapy with a diuretic or calcium channel blocker. Despite these recommendations, the major obstacles to hypertension treatment are systemic and include the availability and cost of medications, the adequacy of health facilities and systems, and the lack of health insurance to address affordability. New and innovative systems-oriented approaches are needed to address the burden of hypertension on a platform of global equity.

[Latin American consensus on hypertension in patients with diabetes type 2 and metabolic syndrome]

The present document has been prepared by a group of experts, members of cardiology, endocrinology, internal medicine, nephrology and diabetes societies of Latin American countries, to serve as a guide to physicians taking care of patients with diabetes, hypertension and comorbidities or complications of both conditions. Although the concept of metabolic syndrome is currently disputed, the higher prevalence in Latin America of that cluster of metabolic alterations has suggested that metabolic syndrome is a useful nosography entity in the context of Latin American medicine. Therefore, in the present document, particular attention is paid to this syndrome in order to alert physicians on a particular high-risk population, usually underestimated and undertreated. These recommendations result from presentations and debates by discussion panels during a 2-day conference held in Bucaramanga, in October 2012, and all the participants have approved the final conclusions. The authors acknowledge that the publication and diffusion of guidelines do not suffice to achieve the recommended changes in diagnostic or therapeutic strategies, and plan suitable interventions overcoming knowledge, attitude and behavioural barriers, preventing both physicians and patients from effectively adhering to guideline recommendations.

Hypertension control in a large multi-ethnic cohort in Amsterdam, The Netherlands: the HELIUS study

OBJECTIVE

Hypertension is a major problem among European ethnic minority groups. We assessed the current situation of hypertension prevalence and its management among a multi-ethnic population in Amsterdam, The Netherlands.

METHODS

Data from the HELIUS study were used including 12,974 participants (1871 Ghanaian, 2184 African Surinamese, 2278 South-Asian Surinamese, 2277 Turkish, 2222 Moroccan and 2142 Dutch origin people), aged 18-70 years. Comparisons among groups were made using proportions and age-adjusted prevalence ratios (PRs).

RESULTS

Hypertension prevalence ranged from 24% and 16% in Moroccan men and women to 52% and 62% in Ghanaian men and women. Except for Moroccan women, age-adjusted PR of hypertension was higher in all the ethnic minority groups than in Dutch. Among hypertensives, ethnic minority groups generally had higher levels of hypertension awareness and BP lowering treatment than Dutch. Moreover, prevalence rates for the prescription of more than one BP lowering drug were generally higher in African and South-Asian origin groups compared with Dutch origin people. By contrast, BP control levels were lower in all the ethnic groups than in Dutch, with control rates being significantly lower in Ghanaian men (26%, PR=0.49; 95% CI, 0.37-0.66) and women (45%, PR=0.64; 0.52-0.77), African-Surinamese men (30%, PR=0.61; 0.46-0.81) and women (45%, PR=0.72; 0.51-0.77), and South-Asian Surinamese men (43%, PR=0.77; 0.61-0.97) and women (47%, PR=0.76; 0.63-0.92) compared with Dutch men (53%) and women (61%).

CONCLUSION

Our findings indicate poor BP control in ethnic minority groups despite the high treatment levels. More work is needed to unravel the potential factors contributing to the poor control in order to improve BP control in ethnic minority groups, particularly among African and South-Asian origin groups.

Efficacy of newer versus older antihypertensive drugs in black patients living in sub-Saharan Africa

To address the epidemic of hypertension in blacks born and living in sub-Saharan Africa, we compared in a randomised clinical trial (NCT01030458) single-pill combinations of old and new antihypertensive drugs in patients (30-69 years) with uncomplicated hypertension (140-179/90-109 mm Hg). After ≥4 weeks off treatment, 183 of 294 screened patients were assigned to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg (n=89; R) or amlodipine/valsartan 5/160 mg (n=94; E) and followed up for 6 months. To control blood pressure (<140/<90 mm Hg), bisoprolol and amlodipine could be doubled (10 mg per day) and α-methyldopa (0.5-2 g per day) added. Sitting blood pressure fell by 19.5/12.0 mm Hg in R patients and by 24.8/13.2 mm Hg in E patients and heart rate decreased by 9.7 beats per minute in R patients with no change in E patients (-0.2 beats per minute). The between-group differences (R minus E) were 5.2 mm Hg (P<0.0001) systolic, 1.3 mm Hg (P=0.12) diastolic, and 9.6 beats per minute (P<0.0001). In 57 R and 67 E patients with data available at all visits, these estimates were 5.5 mm Hg (P<0.0001) systolic, 1.8 mm Hg (P=0.07) diastolic and 9.8 beats per minute (P<0.0001). In R compared with E patients, 45 vs 37% (P=0.13) proceeded to the higher dose of randomised treatment and 33 vs 9% (P<0.0001) had α-methyldopa added. There were no between-group differences in symptoms except for ankle oedema in E patients (P=0.012). In conclusion, new compared with old drugs lowered systolic blood pressure more and therefore controlled hypertension better in native African black patients.

Latin American consensus on hypertension in patients with diabetes type 2 and metabolic syndrome

The present document has been prepared by a group of experts, members of cardiology, endocrinology and diabetes societies of Latin American countries, to serve as a guide to physicians taking care of patients with diabetes, hypertension and comorbidities or complications of both conditions. Although the concept of 'metabolic syndrome' is currently disputed, the higher prevalence in Latin America of that cluster of metabolic alterations has suggested that 'metabolic syndrome' is a useful nosographic entity in the context of Latin American medicine. Therefore, in the present document, particular attention is paid to this syndrome in order to alert physicians on a particularly high-risk population, usually underestimated and undertreated. These recommendations result from presentations and debates by discussion panels during a 2-day conference held in Bucaramanga, in October 2012, and all the participants have approved the final conclusions. The authors acknowledge that the publication and diffusion of guidelines do not suffice to achieve the recommended changes in diagnostic or therapeutic strategies, and plan suitable interventions overcoming knowledge, attitude and behavioural barriers, preventing both physicians and patients from effectively adhering to guideline recommendations.

Efficacy of initiating therapy with amlodipine and hydrochlorothiazide or their combination in hypertensive Nigerians

In order to evaluate whether amlodipine or hydrochlorothiazide would be preferable to initiate therapy, 90 untreated hypertensive Nigerians of both genders aged 31-86 years with blood pressure >160/90 and ≤180/120 mm Hg were recruited into a randomized 48-week study. Patients, 30 each in amlodipine, hydrochlorothiazide, and amlodipine-hydrochlorothiazide groups, were treated, respectively, with amlodipine 5 mg for 6 weeks and the dose increased to 10 mg till week 12, after which hydrochlorothiazide 25 mg was added; hydrochlorothiazide 25 mg till week 6, after which amlodipine 5-10 mg was added; and amlodipine 5-10 mg + hydrochlorothiazide 25 mg. Body mass index, blood pressure, heart rate, and 24-hour urine volume were evaluated at baseline and at the end of weeks 1, 3, 6, 12, 24, 36, and 48. The primary efficacy variables were decreased in mean trough sitting diastolic and systolic blood pressure such that blood pressure < 140/90 mm Hg was regarded as normalized. At week 48 in the amlodipine group, 27 patients versus 25 patients in the hydrochlorothiazide group had diastolic blood pressure <90 mm Hg (90% vs. 83.3%; P <.03). In the amlodipine group, 23 patients versus 20 patients in the hydrochlorothiazide group had blood pressure < 140/90 mm Hg (76.7% vs. 66.7%; P <.01). In the amlodipine-hydrochlorothiazide group, 27 patients (90%) and 15 patients (50%) had diastolic blood pressure <90 mm Hg and blood pressure < 140/90 mm Hg, respectively. This study has demonstrated that a regimen of amlodipine to which hydrochlorothiazide is subsequently added provides superior efficacy on blood pressure control when compared with a regimen of hydrochlorothiazide to which amlodipine is subsequently added or with ab initio amlodipine-hydrochlorothiazide combination therapy.

Relationship Between On-Treatment Decreases in Inappropriate Versus Absolute or Indexed Left Ventricular Mass and Increases in Ejection Fraction in Hypertension

Although in cross-sectional studies left ventricular mass (LVM), which exceeds that predicted by workload (inappropriate LVM [LVM inappr ]) but not absolute LVM or LVM index (LVMI), is inversely related to LV ejection fraction (EF), whether on-treatment decreases in LVM inappr (%observed/predicted LVM) account for increases in EF beyond LVM or LVMI is unclear. Echocardiography was performed in 168 mild-to-moderate hypertensives treated for 4 months. Although in patients with an LVMI >51 g/m 2.7 (n=112; change in LVMI, −13.7±14.0 g/m 2.7 ; P <0.0001) but not in patients with an LVMI ≤51 g/m 2.7 (n=56; change in LVMI, 1.3±9.3 g/m 2.7 ) LVMI decreased with treatment, treatment failed to increase EF in either group (1.2±10.8% and 2.7±10.7%, respectively). In contrast, in patients with inappropriate LV hypertrophy (LVM inappr >150%; n=33) LVM inappr decreased (−32±27%; P <0.0001) and EF increased (5.0±10.3%; P <0.05) after treatment, whereas in patients with an LVM inappr ≤150% (n=135), neither LVM inappr (−0.5±23%) nor EF (0.9±10.3%) changed with therapy. With adjustments for circumferential LV wall stress and other confounders, whereas on-treatment decreases in LVM or LVMI were weakly related to an attenuated EF (partial r =0.17; P <0.05), on-treatment decreases in LVM inappr were strongly related to increases in EF even after further adjustments for LVM or LVMI (partial r =−0.63 [CI, −0.71 to −0.52]; P <0.0001). In conclusion, decreases in LVM inappr are strongly related to on-treatment increases in EF beyond changes in LVM and LVMI. LV hypertrophy can, therefore, be viewed as a compensatory change that preserves EF, but when in excess of that predicted by stroke work, it can be viewed as a pathophysiological process accounting for a reduced EF.

Prevalence of residual left ventricular structural changes after one year of antihypertensive treatment in patients of African descent: role of 24-hour pulse pressure

OBJECTIVES

One year of antihypertensive therapy may normalise left ventricular (LV) structure in 51% of hypertensive patients of European descent. Whether similar effects can be achieved in patients of African descent, who have a high prevalence of concentric LV hypertrophy (LVH) and remodelling, is unknown.

METHODS

In 103 hypertensive patients in the Baragwanath Hypertension study we evaluated the prevalence of residual LV structural changes (echocardiography) after four and 13 months of stepwise antihypertensive therapy.

RESULTS

After 13 months of therapy, 24-hour blood pressure control was achieved in 47% of patients. At baseline, 51.5% of patients had concentric LVH, 19% eccentric LVH and 12% concentric LV remodelling. Despite changes in LV mass index (p < 0.01) and relative wall thickness (p < 0.05) with treatment, the proportion of patients with a normal LV mass or geometry increased only from 17.5 to 25% (p > 0.05), while 26% remained with concentric LVH (p < 0.001 compared to baseline), 25% with eccentric LVH and 23% with concentric LV remodelling (p < 0.05 compared to baseline). Residual structural changes were associated with 24-hour pulse pressure (p = 0.02), but not with 24-hour systolic or diastolic blood pressure or clinic blood pressure.

CONCLUSIONS

Even after a year of antihypertensive therapy, a high proportion (74%) of hypertensives of African ancestry retained residual LV structural changes, an effect that was associated with 24-hour pulse pressure but not systolic or diastolic blood pressures or clinic blood pressure in this ethnic group.

Endogenous nitric oxide formation correlates negatively with circulating matrix metalloproteinase (MMP)-2 and MMP-9 levels in black subjects

Deficient formation of endogenous nitric oxide (NO) contributes to cardiovascular diseases, and this may be associated with increased circulating levels of matrix metalloproteinase-9 (MMP-9), as previously shown in white subjects. Because interethnic differences exist with respect to risk factors, prevalence, and severity of cardiovascular diseases, we designed this study to examine whether the circulating levels of nitrites (a marker of endogenous NO formation) are associated with the plasma levels of MMP-9 and MMP-2 in healthy black subjects. We studied 198 healthy subjects self-reported as blacks not taking any medications. Venous blood samples were collected and plasma and whole blood nitrite levels were measured using an ozone-based chemiluminescence assay. Plasma MMP-2 and MMP-9 levels were determined by gelatin zymography. We found a positive correlation between plasma MMP-9 and MMP-2 levels (P < 0.0001, rs = 0.556). Interestingly, we found a negative relationship between the plasma MMP-9 levels and the plasma or whole blood nitrites levels (P = 0.04, rs = -0.149; and P < 0.0001, rs = -0.349, respectively). In parallel, we found similar negative relationships between plasma MMP-2 levels and plasma or whole blood nitrites levels (P = 0.02, rs = -0.172; and P < 0.0001, rs = -0.454, respectively). This is the first study to show that endogenous nitric oxide formation correlates negatively with the circulating levels of both MMP-2 and MMP-9 in black subjects. Our findings suggest a mechanistic link between deficient NO formation and increased MMPs levels, which may promote cardiovascular diseases.

Achieving blood preSsure goals sTudy in uncontrolled hypeRtensive pAtients treated with a fixed-dose combination of ramipriL/hydrochlorothiazide: the ASTRAL study

Background

Hypertension is a common cardiovascular disease, affecting adults worldwide and it accounts for up to 30% of all deaths. The need for better control of arterial hypertension justifies observational studies designed to better understand the real-life management of hypertensive patients. The ASTRAL study was primarily designed to evaluate the percentage of hypertensive patients achieving blood pressure goals after eight weeks of treatment with a fixed-dose combination of ramipril/hydrochlorothiazide (HCTZ).

Methods

The study was a multi-centre, non-comparative, open-label, observational study conducted in 36 centres in five sub-Saharan African countries, namely Cameroon, Congo Brazzaville, Democratic Republic of Congo (DRC), Madagascar and Nigeria. Four hundred and forty-nine men and women 18 years of age or older with hypertension not controlled by an ACE inhibitor, a diuretic or any other monotherapy or anti-hypertensive combination not containing a diuretic in a fixed dose were considered eligible for inclusion in this eight-week study. The study consisted of three visits, visit one (V1) at baseline, visit two (V2) after four weeks and visit three (V3) after eight weeks.

Results

The mean age of the patients was 54.7 ± 11.7 years (20–90 years) and most were categorised by the WHO criteria as either overweight or obese (71.6%). After four and eight weeks of treatment with the study drug, systolic and diastolic blood pressures significantly changed from baseline: –24.7/–14.2 mmHg (p < 0.001) and –31.7/–17.9 mmHg (p < 0.001), respectively. There were 60.2% of the non-diabetics on prior monotherapy who, at eight weeks, fulfilled the primary blood pressure goal for SBP and DBP, versus 26.5% of the diabetic patients, also on monotherapy. Few adverse events were reported, with facial oedema and dry cough recurring twice in two patients.

Conclusion

Fixed-dose combination of ramipril/HCTZ is therefore effective, tolerable and has a good safety profile for blood pressure control in black Africans.

Management of hypertension at the community level in sub-Saharan Africa (SSA): towards a rational use of available resources

Hypertension is emerging in many developing nations as a leading cause of cardiovascular mortality, morbidity and disability in adults. In sub-Saharan African (SSA) countries it has specificities such as occurring in young and active adults, resulting in severe complications dominated by heart failure and taking place in limited-resource settings in which an individual's access to treatment (affordability) is very limited. Within this context of restrained economic conditions, the greatest gains for SSA in controlling the hypertension epidemic lie in its prevention. Attempts should be made to detect hypertensive patients early before irreversible organ damage becomes apparent, and to provide them with the best possible and affordable non-pharmacological and pharmacological treatment. Therefore, efforts should be made for detection and early management at the community level. In this context, a standardized algorithm of management can help in the rational use of available resources. Although many international and regional guidelines have been published, they cannot apply to SSA settings because the economy of the countries and affordability of the patients do not allow access to advocated treatment. In addition, none of them suggest a clear algorithm of management for limited-resource settings at the community level. In line with available data and analysing existing guidelines, a practical algorithm for management of hypertension at the community level, including treatment affordability, has been suggested in the present work.

How to treat hypertension in blacks: review of the evidence

Presentation, response to therapy, and clinical outcome differ according to race for patients with hypertension. Black patients have a higher prevalence and earlier onset of hypertension than other ethnic groups, with poorer prognosis than white patients. Blacks are more likely to be salt-sensitive, and to have a low plasma renin activity than are whites. They are at much greater risk of developing cardiovascular and renal complications. Despite many advances in the understanding and treatment of cardiovascular diseases, black patients continue to have increased morbidity and mortality from the end-organ complications of hypertension. The explanations for these observations remain incompletely understood, but genetic differences, added to socio-economic and environmental factors, have been proposed to explain this disparity. The first therapeutic approach is to decrease salt and increase potassium intakes. Diuretics (thiazides and potassium-sparing agents) and calcium channel blockers constitute the first antihypertensive drug choices. The angiotensin-converting-enzyme inhibitors, the angiotensin II receptor blockers and beta-blockers appear to be less effective in blacks with regard to uncomplicated hypertension, especially in older people, but addition of a small dose of diuretic improves their efficacy. These combinations are preferred among patients with chronic kidney disease or heart failure. The goal for blood pressure target is the same in blacks as it is in whites, being a blood pressure of less than 140/90 mmHg in uncomplicated hypertension and less than 130/80 mmHg in patients with diabetes mellitus or chronic kidney disease.

Endothelial nitric oxide synthase polymorphisms and haplotypes in Amerindians

Interethnic disparities in the distribution of endothelial nitric oxide synthase (eNOS) polymorphisms may affect nitric oxide (NO)-mediated effects of and responses to drugs. While there are differences between black and white subjects there is no information regarding the distribution of eNOS gene alleles and haplotypes in Amerindians. We studied three clinically relevant eNOS polymorphisms (T(-786)C in the promoter, a variable number of tandem repeats in intron 4, and the Glu298Asp in exon 7) and eNOS haplotypes in 170 Amerindians from three tribes of the Brazilian Amazon. The results were compared with previous findings for black and white Brazilians. The Asp298, C(-786), and 4a alleles were much less common in Amerindians (5.0%, 3.2%, and 4.1%, respectively) than in blacks (15.1%, 19.5%, and 32.0%, respectively) or whites (32.8%, 41.9%, and 17.9%, respectively) (p < 0.001). The haplotype including the most common alleles for each polymorphism was much more common in Amerindians (89%) than in blacks (45%) or whites (41%). Our findings are consistent with a lower genetic diversity in Amerindians compared with blacks and whites. These striking differences may be of major relevance for case-control association studies focusing on eNOS gene polymorphisms and may explain, at least in part, differences in the responses to cardiovascular drugs.

Obesity promotes left ventricular concentric rather than eccentric geometric remodeling and hypertrophy independent of blood pressure

BACKGROUND

As it is uncertain whether excess adiposity promotes primarily concentric or eccentric left ventricular hypertrophy (LVH), we aimed to determine at a population level, the independent relationship between waist circumference (WC) and LV geometric changes and the potential hemodynamic mechanisms thereof.

METHODS

We assessed the relations between WC and LV end-diastolic diameter (EDD), LV mean wall thickness (MWT = posterior + septal wall thickness/2), LV relative wall thickness (RWT = MWT/EDD), LV mass index (LVMI), concentric LVH (LVMI > 51 g/m2.7 and RWT > 0.45), eccentric LVH (LVMI > 51 g/m2.7 and RWT < 0.45), or concentric LV remodeling (normal LVMI and RWT > 0.45), in 309 never treated for hypertension, randomly recruited adult participants with a high prevalence of excess adiposity ( approximately 25% overweight; 38% obese). Pulse-wave analysis was performed to determine central artery blood pressures (BPs). Two hundred and thirty-one participants had high-quality ambulatory BP monitoring.

RESULTS

Approximately 7% of participants had concentric LVH, approximately 16% concentric LV remodeling, and approximately 15% eccentric LVH. After adjustments for potential confounders including conventional systolic BP (SBP), WC was related to MWT (partial r = 0.23, P = 0.0001), RWT (partial r = 0.13, P = 0.03), concentric LVH (P < 0.04), concentric LV remodeling (P = 0.02), but not with EDD or eccentric LVH (P = 0.91). Similar outcomes were noted after adjustments for central or 24-h SBP, and for conventional, central, or 24-h pulse pressure. Separate analysis in normotensive subjects revealed similar outcomes.

CONCLUSIONS

In a population sample with a high prevalence of obesity, excess adiposity promotes concentric, rather than eccentric LV geometric changes, effects which are independent of conventional, central artery or 24-h BP measured on a single occasion.

Diagnosis and treatment of low-renin hypertension

Plasma renin levels can be used to classify hypertension. A significant proportion of hypertensive individuals display a low-renin profile and thus low-renin hypertension (LRH) requires appropriate diagnosis and treatment. LRH includes essential, secondary and genetic forms, the most common of which are low-renin essential hypertension and primary aldosteronism. Several studies have investigated the relationship between PRA status and clinical response to different antihypertensive therapies. The present review will discuss the differential diagnosis of LRH subtypes and the most appropriate treatment options based on the pathophysiological background of this condition.

WITHDRAWN: Effect of antihypertensive drugs on mortality, morbidity and blood pressure in blacks

BACKGROUND

Black people have a greater prevalence of elevated blood pressure leading to excess morbidity and mortality.

OBJECTIVES

To systematically review the effects of different antihypertensive drugs on mortality, morbidity and blood pressure black adults with elevated blood pressure.

SEARCH STRATEGY

Medline, Embase, LILACS, African Index Medicus, the Cochrane Library November 2003; Pubmed September 2003 to March 2004. Searches were conducted without language restriction.

SELECTION CRITERIA

Randomised controlled trials of drugs versus placebo (blood pressure outcomes) or versus placebo or other drugs (morbidity and mortality outcomes).

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data unblinded. Disagreements were resolved by discussion. Authors were contacted twice to obtain missing information.

MAIN RESULTS

Full reports or abstracts from more than 2900 references of papers yielded 30 trials considering 53 interventions with 8 classes of antihypertensive drugs in 20,006 black patients from Africa, the Caribbean, and the United States of America, aged 18 to >80 years. In one large trial the main morbidity and mortality outcomes did not differ significantly between initial treatment drug classes when drugs were added to reach goal blood pressures. However, the comparison ACE Inhibitors vs diuretic favoured the diuretic for stroke 1.40 [1.17 to 1.68]; combined CHD 1.15 [1.02 to 1.30] and combined CVD 1.19 [1.09 to 1.30] and the comparison alpha blocker vs diuretic favoured the diuretic for combined CVD 1.40 [1.25 to 1.57]. In addition, all comparisons for heart failure favoured diuretic (1.47 [1.24 to 1.74] vs calcium blocker; 1.32 [1.11 to 1.58] vs ACE Inhibitor; and 2.18 [1.73 to 2.74] vs alpha blocker. The results also showed a greater occurrence of diabetes with diuretics. No significant differences were detected between placebo and beta adrenergic blockers in the reduction of systolic blood pressure (weighted mean difference [95% CI], -3.52 [-7.50 to 0.46] mm Hg). In addition, ACE inhibitors did not significantly differ from placebo in achievement of goal diastolic blood pressure (risk difference [95% CI], 5% [-10% to 21%]). Calcium blockers, diuretics, centrally acting agents, alpha adrenergic blockers and angiotensin II antagonists were all more effective than placebo in reducing blood pressure in the pooled analyses. Only calcium blockers remained effective in all prespecified subgroups, including baseline diastolic blood pressure >109 mm Hg.

AUTHORS' CONCLUSIONS

When first-line drugs from different classes are compared in the treatment of black people, there is no evidence of differential effects on most mortality and morbidity outcomes. Those morbidity differences that were found favoured diuretics. Drugs differ in their ability to reduce blood pressure in black people. Calcium blockers were the only drug class that reduced blood pressure in all subgroups of black people including those with severe hypertension. Beta-blockers, angiotensin receptor blocker, alpha blockers and ACE Inhibitors were least good at reducing blood pressure in black adults.

Getting to goal in complex patients

Traditionally, the term complex hypertension has been applied to patients who have clinical evidence of target organ damage. However, this definition can be expanded to include many hypertensive patients who either present without manifest disease but harbor silent concomitant organ damage, or belong to a high-risk group and are likely to develop such damage. Thus, the number of patients who deserve special consideration as complex patients is considerable. Various factors may contribute toward classifying a patient as having complex hypertension. These include severe hypertension, concomitant conditions such as diabetes, chronic renal insufficiency, coronary artery disease, orcongestive heart failure; and high-risk populations such as the elderly and African Americans. Recent evidence demonstrates that aggressive goal blood pressure (BP)-lowering therapy is the key toward halting the progression of vascular disease. Although the choice of initial therapy seems less important than achieving goal BP, the drug selected must impart efficacy, organ protection, and tolerability. Combination therapy consisting of calcium-channel blockers and angiotensin-converting enzyme inhibitors seems to achieve these desirable effects. Several clinical trials have demonstrated these agents to have favorable effects on BP and organ protection even in complex hypertension, particularly when used in combination.

Pharmacologic Agents in the Management of Hypertension-Nisoldipine Coat-Core

Nisoldipine coat-core (CC), a 1,4-dihydropyridine calcium antagonist, is indicated for the treatment of hypertension and may be used alone or in combination with other antihypertensive agents. The CC technology allows for extended delivery of the drug and once-daily dosing. Nisoldipine CC tablets are absorbed across the entire gastrointestinal tract, including the colon. Eighty percent of the total dose is in the slow-release outer coat, while the core has immediate-release characteristics suitable for absorption in the distal gastrointestinal tract. Numerous double-blind, randomized studies of this agent have been done in patients with hypertension. The use of nisoldipine CC reduced both clinic and ambulatory blood pressure to a similar degree when compared with angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, and the calcium antagonists amlodipine and felodipine. The drug has also been studied in hypertensive African Americans and demonstrated equivalent efficacy to amlodipine. Tolerability of the drug is good, with the most common side effect of edema at a rate similar to other dihydropyridine calcium antagonists. Thus, results of more than a decade of clinical trial data support the use of nisoldipine CC as once-daily therapy for the treatment of hypertension.

Functional variants of the angiotensinogen gene determine antihypertensive responses to angiotensin-converting enzyme inhibitors in subjects of African origin

OBJECTIVE

To determine whether the response to angiotensin-converting enzyme inhibitor (ACEI) monotherapy in subjects of African origin is determined by genetic variants within the angiotensinogen (AGT) gene.

METHODS

A total of 194 hypertensive patients of African ancestry were recruited from district clinics in Johannesburg, South Africa. Eighty patients received open-label ACEI (enalapril or lisinopril) monotherapy, and 114 open-label calcium antagonist (nifedipine) as a drug class comparator. Twenty-four hour ambulatory blood pressure (ABP) monitoring was performed at baseline (off medication) and after 2 months of therapy. DNA was analysed for functional variants (-217G-->A and -20A-->C) of the AGT gene. The impact of genotype on ABP responses to ACEI monotherapy or calcium antagonists; and on plasma aldosterone and renin levels after ACEI monotherapy was assessed.

RESULTS

Adjusting for baseline ABP and type of ACEI in the ACEI-treated group, the -217G-->A variant predicted ABP responses to ACEI (n = 77; P < 0.01), but not to nifedipine (n = 108). ACEI in patients with the AA genotype of the -217G-->A variant failed to elicit an antihypertensive response [change in ABP, mmHg: systolic blood pressure (SBP) +0.84 +/- 2.89, P = 0.78; diastolic blood pressure (DBP) -0.47 +/- 1.74, P = 0.79]. In contrast, those patients with at least one copy of the -217G allele developed a 7.23 +/- 1.55 and 5.38 +/- 1.12 mmHg decrease (P < 0.0001) in SBP and DBP, respectively, after ACEI administration. Similarly, the -20A-->C variant predicted ABP responses to ACEI monotherapy (P < 0.01) but not to nifedipine. Moreover, patients who were AA genotype for both variants failed to develop an antihypertensive response to ACEI (change in ABP, mmHg: SBP +1.06 +/- 3.05, P = 0.73; DBP -0.39 +/- 1.83, P = 0.83); whereas patients with at least one copy of both the -217G and the -20C allele developed substantial decreases in ABP (change in ABP, mmHg: SBP -14.08 +/- 3.72, P < 0.0001; DBP -9.62 +/- 2.74, P < 0.0001). Patients with at least one copy of the -217G allele demonstrated a significant reduction in the aldosterone-to-renin ratio (-0.098 +/- 0.035, P < 0.01), whereas in those patients who were -217AA genotype the ratio was unchanged (-0.03 +/- 0.16, P = 0.85).

CONCLUSION

Functional variants of the AGT gene contribute to the variability of antihypertensive responses to ACEI monotherapy in individuals of African ancestry, with genotype determining whether or not responses occur.

Hypertension artérielle du sujet noir

Hypertension is more frequent and more severe in blacks than in other racial groups. Salt-sensitive and low-renin hypertension are both more frequent in blacks. Cardiovascular morbidity appears to be similar in blacks and whites and depends on the classic cardiovascular risk factors. Kidney damage leading to end-stage renal disease is more frequent in blacks. Reduced salt intake improves drug efficacy. Diuretics and calcium channel blockers are more effective in lowering blood pressure, while angiotensin-converting-enzyme inhibitors may be more effective in preventing organ damage. Specific trials are needed to evaluate therapeutic benefits in blacks.

Hypertension in sub-Saharan African populations

BACKGROUND

Hypertension in sub-Saharan Africa is a widespread problem of immense economic importance because of its high prevalence in urban areas, its frequent underdiagnosis, and the severity of its complications.

METHODS AND RESULTS

We searched PubMed and relevant journals for words in the title of this article. Among the major problems in making headway toward better detection and treatment are the limited resources of many African countries. Relatively recent environmental changes seem to be adverse. Mass migration from rural to periurban and urban areas probably accounts, at least in part, for the high incidence of hypertension in urban black Africans. In the remaining semirural areas, inroads in lifestyle changes associated with "civilization" may explain the apparently rising prevalence of hypertension. Overall, significant segments of the African population are still afflicted by severe poverty, famine, and civil strife, making the overall prevalence of hypertension difficult to determine. Black South Africans have a stroke rate twice as high as that of whites. Two lifestyle changes that are feasible and should help to stem the epidemic of hypertension in Africa are a decreased salt intake and decreased obesity, especially in women.

CONCLUSIONS

Overall, differences from whites in etiology and therapeutic responses in sub-Saharan African populations are graded and overlapping rather than absolute. Further studies are needed on black Africans, who may (or may not) be genetically and environmentally different from black Americans and from each other in different parts of this vast continent.

Consistent interethnic differences in the distribution of clinically relevant endothelial nitric oxide synthase genetic polymorphisms

A maldistribution of endothelial nitric oxide synthase (eNOS) genetic variants may explain differences in NO-mediated effects and response to drugs among black and white subjects. While interethnic differences in the distribution of eNOS genetic variants exist in the American population, it is not known whether such interethnic differences exist in other populations. To test this possibility, we examined the distribution of genetic variants of three clinically relevant eNOS polymorphisms (T(-786)C in the promoter, the VNTR in intron 4, and the Glu298Asp variant in exon 7) in 136 black and 154 white subjects from a Brazilian population, which is very heterogeneous. We also estimated the haplotype frequency and evaluated associations between these variants. The Asp298 variant was more common in whites (32.8%) than in blacks (15.1%) (P < 0.004). Similarly, the C(-786) variant was more common in whites (41.9%) than in blacks (19.5%) (P < 0.0004). However, the 4a variant was more common in blacks (32.0%) than in whites (17.9%) (P < 0.003). The most common predicted haplotype in both ethnic groups combined only wild-type variants. While the second most common haplotype in blacks includes the variant 4a and the wild-type variants for the remaining polymorphisms, the second most common haplotype in whites includes the variants Asp298 and C(-786) and the wild-type variant for polymorphism in intron 4. The marked interethnic differences that we found in Brazilians are very similar to those previously reported in Americans. These findings strongly suggest a consistent difference in the distribution of eNOS genetic variants in blacks compared with whites and indicate that the interethnic differences do not vary with geographic origin.

Blood Pressure Reduction and Cardiovascular Prevention: An Update Including the 2003-2004 Secondary Prevention Trials

In a meta-analysis published in June 2003, we reported that new and old classes of antihypertensive drugs had similar long-term efficacy and safety. Furthermore, we observed that in clinical trials in hypertensive or high-risk patients gradients in systolic blood pressure (SBP) accounted for most differences in outcome. To test whether our previous conclusions would hold, we updated our quantitative overview with new information from clinical trials published before 2005. To compare new and old antihypertensive drugs, we computed pooled odds ratios from stratified 2 x 2 contingency tables. In a meta-regression analysis, we correlated these odds ratios with corresponding between-group differences in SBP. We then contrasted observed odds ratios with those predicted from gradients in SBP. The main finding of our overview was that reduction in SBP largely explained cardiovascular outcomes in the recently published actively controlled trials in hypertensive patients and in placebo-controlled secondary prevention trials. The published results suggested that dihydropyridine calcium-channel blockers might offer a selective benefit in the prevention of stroke and inhibitors of the renin-angiotensin system in the prevention of heart failure. For prevention of myocardial infarction, the published results were more equivocal, because of the benefit of amlodipine over placebo or valsartan in 2 trials, whereas other placebo-controlled trials of calcium-channel blockers or angiotensin converting enzyme inhibitors did not substantiate the expected benefit with regard to cardiac outcomes. In conclusion, the hypothesis that new antihypertensive drugs might influence cardiovascular prognosis over and beyond their antihypertensive effect remains unproven. Our overview emphasizes the need of tight blood pressure control, but does not allow determining to what extent blood pressure must be lowered for optimal cardiovascular prevention.

Gender difference in the response to an angiotensin-converting enzyme inhibitor and a diuretic in hypertensive patients of African descent

BACKGROUND

The efficacy of angiotensin-converting enzyme (ACE) inhibitors in decreasing blood pressure in African patients is controversial.

OBJECTIVE

We examined the ambulatory blood pressure (ABP) response to a diuretic and an ACE inhibitor in hypertensive patients of East African descent and evaluated the individual characteristics that determined treatment efficacy.

DESIGN

A single-blind randomized AB/BA crossover design.

SETTING

Hypertensive families of East African descent from the general population in the Seychelles.

PARTICIPANTS

Fifty-two (29 men and 23 women) out of 62 eligible hypertensive patients were included.Main outcome measures ABP response to 20 mg lisinopril (LIS) daily and 25 mg hydrochlorothiazide (HCT) daily given for a 4-week period. Results The daytime systolic/diastolic ABP response to HCT was 4.9 [95% confidence interval (CI) 1.2-8.6]/3.6 (1.0-6.2) mmHg for men and 12.9 (9.2-16.6)/6.3 (3.7-8.8) mmHg for women. With LIS the response was 18.8 (15.0-22.5)/14.6 (12.0-17.1) mmHg for men and 12.4 (8.7-16.2)/7.7 (5.1-10.2) mmHg for women. The night-time systolic/diastolic response to HCT was 5.0 (0.6-9.4)/2.7 [(-0.4)-5.7] mmHg for men and 11.5 (7.1-16.0)/5.7 (2.6-8.8) mmHg for women, and to LIS was 18.7 (14.2-22.1)/15.4 (12.4-18.5) mmHg for men and 3.5 [(-1.0)-7.9]/2.3 [(-0.8)-5.4] mmHg for women. Linear regression analyses showed that gender is an independent predictor of the ABP responses to HCT and to LIS.

CONCLUSIONS

Hypertensive patients of African descent responded better to LIS than to HCT. Men responded better to LIS than to HCT and women responded similarly to both drugs.

Calcium channel blockers: an update

This paper reviews the current literature pertaining to calcium channel blockers, including their classification, properties, and therapeutic indications, in light of several recent trials that have addressed their safety. Calcium channel blockers are a structurally and functionally heterogeneous group of medications that are used widely to control blood pressure and manage symptoms of angina. They are classified as dihydropyridines or nondihydropyridines. As a class, they are well tolerated and are associated with few side effects. The question of whether they may precipitate cardiovascular events has been largely settled by recent trials, such as the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), the International Verapamil Slow-Release/Trandolapril Study (INVEST), and the Controlled Onset Verapamil Investigation of Cardiovascular Endpoints (CONVINCE) study, in which no such association was found. Even so, the use of these agents has been linked with an increased risk of heart failure. Thus, long-acting calcium channel blockers may be safely used in the management of hypertension and angina. However, as a class, they are not as protective as other antihypertensive agents against heart failure.

Systematic Review of Progressive Resistance Strength Training in Older Adults

BACKGROUND

The aim of this systematic review was to quantify the effectiveness of progressive resistance strength training (PRT) to reduce physical disability in older people.

METHODS

Randomized controlled trials were identified from searches of relevant databases and study reference lists and contacts with researchers. Two reviewers independently screened the trials for eligibility, rated their quality, and extracted data. Only randomized controlled trials utilizing PRT as the primary intervention in participants, whose group mean age was 60 years or older, were included. Data were pooled using fixed or random effect models to produce weighted mean differences (WMD) and 95% confidence intervals (CI). Standardized mean differences (SMD) were calculated when different units of measurement were used for the outcome of interest.

RESULTS

62 trials (n = 3674) compared PRT with a control group. 14 trials had data available to allow pooling of disability outcomes. Most trials were of poor quality. PRT showed a strong positive effect on strength, although there was significant heterogeneity (41 trials [n = 1955], SMD 0.68; 95% confidence interval [CI] 0.52, 0.84). A modest effect was found on some measures of functional limitations such as gait speed (14 trials [n = 798], WMD 0.07 meters per second; 95% CI 0.04, 0.09). No evidence of an effect was found for physical disability (10 trials [n = 722], SMD 0.01; 95% CI -0.14, 0.16). Adverse events were poorly investigated, but occurred in most studies where they were defined and prospectively monitored.

CONCLUSIONS

PRT results in improvements to muscle strength and some aspects of functional limitation, such as gait speed, in older adults. However, based on current data, the effect of PRT on physical disability remains unclear. Further, due to the poor reporting of adverse events in trials, it is difficult to evaluate the risks associated with PRT.