Comparison of active treatment and placebo in older Chinese patients with isolated systolic hypertension. Systolic Hypertension in China (Syst-China) Collaborative Group

Treatment of hypertension in the elderly in 2010 - a brief review

IMPORTANCE OF THE FIELD

Populations, the world over, age. Prevalence of hypertension increases with advancing age. Despite the advances over the past 30 years, there are still unresolved issues regarding antihypertensive therapy in the elderly.

AREAS COVERED IN THIS REVIEW

The present review discusses the available evidence supporting treatment of hypertension in the elderly.

WHAT THE READER WILL GAIN

In the 1980s and 1990s, a number of trials were performed and proved that active treatment of hypertension in individuals above the age of 60 - 65 years, compared with placebo or no treatment, reduces the risk of complications. In the 1990s, the same was proven in patients specifically affected with isolated systolic hypertension, the predominant form of hypertension in the elderly. The subsequent years witnessed the publication of trials that showed that most antihypertensive drugs are capable of substantially reducing risk. Finally, treatment of hypertension in the very elderly was proven to be beneficial.

TAKE HOME MESSAGE

In spite of these advances, we still lack evidence in elderly patients with mild isolated systolic hypertension and are therefore in need of a properly designed, randomized, placebo-controlled trial.

Hypothesis: it is time to reconsider phenotypes in hypertension

The study of genes and mechanisms associated with hypertension is hampered by the heterogeneity of hypertensive patients. Refining the definition of hypertension is a potential means of improving the clarity of mechanistic studies, but the lack of intermediate phenotypes hinders the assessment of causal relationships. Looking at younger individuals and hemodynamic subsets of hypertension is one such refinement. The authors argue that the separate analysis of patients with isolated diastolic hypertension, predominantly diastolic hypertension, and isolated systolic hypertension in the young in combination with common biomarkers may be an initial step to decrease heterogeneity within patient subsets, thus providing new avenues for genetic and pathophysiological studies.

Does decreased diastolic blood pressure associate with increased mortality in 80-year-old Japanese?

Hypertension is one of the greatest risk factors for cardiovascular disease, but its contribution to cardiovascular mortality weakens with aging. We have previously demonstrated that at the age of 80, higher systolic blood pressure (SBP) is not correlated with increased mortality in Japan. However, we did not examine in detail whether diastolic blood pressure (DBP) independently affects mortality. In the present study, 639 participants, who were 80 years old in 1997, were enrolled. The subjects were divided by their DBP [below 70 mmHg (group 1, n = 136), from 70 mmHg to 80 mmHg (group 2, n = 200), from 80 mmHg to 90 mmHg (group 3, n = 194), over 90 mmHg (group 4, n = 109)]. During the 4-year follow-up period, 90 individuals died. Cox multivariate regression analysis revealed that group 1 showed a significantly higher mortality rate than group 4 [relative risk (RR) 2.47, confidence interval (CI) 1.07-5.70, p = 0.03)]. The relative risks of deaths from cardiovascular diseases, pneumonia, and cancer tended to be higher in group 1 than in group 4, but the difference did not reach statistical significance. These results suggest that decreased DBP is associated with higher mortality in the Japanese elderly.

Hypertension in the elderly

Hypertension is an important risk factor for cardiovascular morbidity and mortality, particularly in the elderly. Blood pressure elevation in the elderly is due to structural and functional changes that occur with aging. Treatment of hypertension reduces the risk of stroke, heart failure, myocardial infarction, all-cause mortality, cognitive impairment, and dementia in elderly patients with hypertension. A healthy lifestyle helps hypertension management, with benefits extending beyond lowering of blood pressure. Several classes of antihypertensive drugs are effective in preventing cardiovascular events. Treatment decisions should be guided by the presence of compelling indications such as diabetes or heart failure and by the tolerability of individual drugs or drug combinations in individual patients. The concomitant intake of certain medications that counter the effects of antihypertensive drugs and the frequent occurrence of orthostatic hypotension complicate treatment in older patients and drive down blood pressure control rates.

Incidence and predictors of hypertension among rural Chinese adults: results from Liaoning province

OBJECTIVE We wanted to determine the incidence of hypertension and its risk factors among rural Chinese adults.

METHODS

A population-based sample of 24,360 rural Chinese adults aged 35 years and older and free from hypertension at baseline was observed from 2004-2006 to 2008. Incident hypertension was defined as a systolic pressure of 140 mm Hg or greater, diastolic pressure of 90 mm Hg or greater, or current use of antihypertensive medication.

RESULTS

During a mean follow-up period of 28 months, 29.6% of men and 23.4% of women developed hypertension. The age-adjusted incidence was higher in men (12.75 per 100 person-years) than in women (10.04 per 100 person-years). Among men, independent predictors of incident hypertension were baseline age (hazard ratio [HR] = 1.11; 95% confidence interval [CI], 1.10-1.13), Mongolian ethnicity (HR = 1.09; 95% CI, 1.01-1.18), use of alcohol, (HR = 1.14; 95% CI, 1.06-1.23), high income vs low income (HR = 1.11; 95% CI, 1.00-1.22; and HR = 1.11; 95% CI, 1.03-1.20), prehypertension vs normotension (HR = 1.18; 95% CI, 1.08-1.28), overweight and obesity (HR = 1.28; 95% CI, 1.17-1.40), baseline salt intake (HR = 1.00; 95% CI, 1.00-1.01) and family history of hypertension (HR = 1.14; 95% CI, 1.03-1.27). With the exception of use of alcohol and mean income, the results were similar for women, except that low physical activity was shown as a risk factors as well. The awareness, treatment, and control rates for newly developed hypertension were 29.9%, 19.5%, and 1.5%, respectively.

CONCLUSIONS

These data indicate that the incidence of hypertension is high among these rural Chinese adults and that it is associated with many risk factors. Our findings further suggest that most newly developed hypertension cases are not treated. The increases in hypertension are probably related to rapid social changes in our country and may apply to other areas of the developing world. These findings call for urgent improvements in hypertension prevention and control programs in rural China.

Blood pressure lowering in patients without prior cerebrovascular disease for prevention of cognitive impairment and dementia

BACKGROUND

This is an update of a previous review (McGuinness 2006).Hypertension and cognitive impairment are prevalent in older people. Hypertension is a direct risk factor for vascular dementia (VaD) and recent studies have suggested hypertension impacts upon prevalence of Alzheimer's disease (AD). Therefore does treatment of hypertension prevent cognitive decline?

OBJECTIVES

To assess the effects of blood pressure lowering treatments for the prevention of dementia and cognitive decline in patients with hypertension but no history of cerebrovascular disease.

SEARCH STRATEGY

The Specialized Register of the Cochrane Dementia and Cognitive Improvement Group, The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL, LILACS as well as many trials databases and grey literature sources were searched on 13 February 2008 using the terms: hypertens$ OR anti-hypertens$.

SELECTION CRITERIA

Randomized, double-blind, placebo controlled trials in which pharmacological or non-pharmacological interventions to lower blood pressure were given for at least six months.

DATA COLLECTION AND ANALYSIS

Two independent reviewers assessed trial quality and extracted data. The following outcomes were assessed: incidence of dementia, cognitive change from baseline, blood pressure level, incidence and severity of side effects and quality of life.

MAIN RESULTS

Four trials including 15,936 hypertensive subjects were identified. Average age was 75.4 years. Mean blood pressure at entry across the studies was 171/86 mmHg. The combined result of the four trials reporting incidence of dementia indicated no significant difference between treatment and placebo (236/7767 versus 259/7660, Odds Ratio (OR) = 0.89, 95% CI 0.74, 1.07) and there was considerable heterogeneity between the trials. The combined results from the three trials reporting change in Mini Mental State Examination (MMSE) did not indicate a benefit from treatment (Weighted Mean Difference (WMD) = 0.42, 95% CI 0.30, 0.53). Both systolic and diastolic blood pressure levels were reduced significantly in the three trials assessing this outcome (WMD = -10.22, 95% CI -10.78, -9.66 for systolic blood pressure, WMD = -4.28, 95% CI -4.58, -3.98 for diastolic blood pressure). Three trials reported adverse effects requiring discontinuation of treatment and the combined results indicated no significant difference (OR = 1.01, 95% CI 0.92, 1.11). When analysed separately, however, more patients on placebo in Syst Eur 1997 were likely to discontinue treatment due to side effects; the converse was true in SHEP 1991. Quality of life data could not be analysed in the four studies. Analysis of the included studies in this review was problematic as many of the control subjects received antihypertensive treatment because their blood pressures exceeded pre-set values. In most cases the study became a comparison between the study drug against a usual antihypertensive regimen.

AUTHORS' CONCLUSIONS

There is no convincing evidence from the trials identified that blood pressure lowering in late-life prevents the development of dementia or cognitive impairment in hypertensive patients with no apparent prior cerebrovascular disease. There were significant problems identified with analysing the data, however, due to the number of patients lost to follow-up and the number of placebo patients who received active treatment. This introduced bias. More robust results may be obtained by conducting a meta-analysis using individual patient data.

Hypertension treatment and management concerns in the elderly

Much of the developed world’s population is aging. Hypertension is a common condition that increases steadily with age and is most prevalent in the elderly. In the last two decades, a number of clinical trials have increased the awareness of the consequences of hypertension and enhanced the understanding of its treatment. Both pharmacologic and nonpharmacologic strategies have been found to be successful in treating hypertension and reducing the frequency of associated morbidity and mortality in the elderly. Moreover, these treatments appear to be well tolerated and feasible to implement in geriatric populations. It is incumbent upon healthcare providers and policymakers alike to diligently pursue judicious management of hypertension in older patients.

Drug treatment of hypertension in older hypertensives

There is strong evidence supporting the benefit of antihypertensive treatment in older patients. Blood pressure goal and drug selection in the elderly is similar to that in younger populations, but there are a few special considerations in these patients. A number of studies have been conducted to determine the drugs or drug classes most effective for reducing cardiovascular complications in older patients with hypertension. This article reviews the evidence for drug treatment in this population.

Comparison of the effects of antihypertensive agents on central blood pressure and arterial stiffness in isolated systolic hypertension

Isolated systolic hypertension is an important risk factor for cardiovascular disease and results primarily from elastic artery stiffening. Although various drug therapies are used to lower peripheral blood pressure (BP) in patients with isolated systolic hypertension, the effects of the 4 major classes of antihypertensive agents on central BP, pulse pressure (PP) amplification, and arterial stiffness in this condition are not clear. Fifty-nine patients over the age of 60 years with untreated isolated systolic hypertension (systolic BP > or =140 mm Hg and diastolic BP Collapse

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MESH Headings

• Administration, Oral
• Aged
• Analysis of Variance
• Antihypertensive Agents/administration & dosage
• Arteries/drug effects
• Arteries/physiopathology
• Atenolol/administration & dosage
• Bendroflumethiazide/administration & dosage
• Blood Pressure Determination/methods
• Dihydropyridines/administration & dosage
• Dose-Response Relationship, Drug
• Double-Blind Method
• Drug Administration Schedule
• Elasticity/drug effects
• Female
• Follow-Up Studies
• Hemodynamics/drug effects
• Hemodynamics/physiology
• Humans
• Hypertension/diagnosis
• Hypertension/drug therapy
• Male
• Middle Aged
• Multivariate Analysis
• Patient Compliance
• Perindopril/administration & dosage
• Probability
• Regression Analysis
• Risk Assessment
• Systole/drug effects
• Systole/physiology
• Treatment Outcome

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Grants

• FS/07/001/21990 British Heart Foundation

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Affiliation(s)

Isla S Mackenzie Clinical Pharmacology Unit, Addenbrooke's Hospital Box 110, Cambridge, CB2 0QQ United Kingdom
Carmel M McEniery
Zahid Dhakam
Morris J Brown
John R Cockcroft
Ian B Wilkinson

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Collaborators Collapse

Latin American guidelines on hypertension. Latin American Expert Group

Hypertension is a highly prevalent cardiovascular risk factor in the world and particularly overwhelming in low and middle-income countries. Recent reports from the WHO and the World Bank highlight the importance of chronic diseases such as hypertension as an obstacle to the achievement of good health status. It must be added that for most low and middle-income countries, deficient strategies of primary healthcare are the major obstacles for blood pressure control. Furthermore, the epidemiology of hypertension and related diseases, healthcare resources and priorities, the socioeconomic status of the population vary considerably in different countries and in different regions of individual countries. Considering the low rates of blood pressure control achieved in Latin America and the benefits that can be expected from an improved control, it was decided to invite specialists from different Latin American countries to analyze the regional situation and to provide a consensus document on detection, evaluation and treatment of hypertension that may prove to be cost-utility adequate. The recommendations here included are the result of preparatory documents by invited experts and a subsequent very active debate by different discussion panels, held during a 2-day sessions in Asuncion, Paraguay, in May 2008. Finally, in order to improve clinical practice, the publication of the guidelines should be followed by implementation of effective interventions capable of overcoming barriers (cognitive, behavioral and affective) preventing attitude changes in both physicians and patients.

How willing are the public to pay for anti-hypertensive drugs for primary prevention of cardiovascular disease: a survey in a Chinese city

BACKGROUND

Current recommendations on drug treatment of hypertension for primary prevention of cardiovascular disease are primarily determined by the evidence of effectiveness, disregard the resources available and values of people, and recommend a universally fixed risk cutoff for initiating drug treatment. The guidelines may have over-estimated the willingness of the public to accept and pay for these drugs and a fixed cutoff may not fit all populations. Moreover, the public may have been misinformed and are unable to make the right decision even if they are consulted. We conducted this study to address these issues and to describe the gap between current policy and what the public truly want.

METHODS

A cross-sectional survey with face-to-face interviews of rural and urban residents in northern China. Before providing any information, we asked the residents whether they would accept drug treatment if they had hypertension and also asked them to estimate the 5-year cardiovascular risk in untreated hypertension and the benefits from anti-hypertensive drugs. We then informed the participants of necessary information and asked them above what benefit they would be willing to pay the current cost, and how much they would be willing to pay for the actual benefit, for anti-hypertensive drugs out of pocket.

RESULTS

Eight hundred and eighty-seven rural residents and 921 urban residents were interviewed with a response rate of 97%. Ninety-five percent [95% confidence interval (CI) 94-96%] of the residents said they would take anti-hypertensive drugs if they had hypertension, although 91% (95% CI 89-92%) said they did not have sufficient knowledge to make a decision. Seventy-eight percent (95% CI 76-80%) believed that anti-hypertensive drugs were primarily to lower blood pressure or relieve symptoms. They over-estimated the cardiovascular risk of untreated hypertension by approximately 12 times and the absolute benefit of drug treatment by 20 times. Given the actual absolute benefit of the drugs, only 23% (95% CI 21-25%) were willing to pay the current annual cost of $500 Ren Min Bi (US$73.3, euro 54.8 as of 8 May 2009) for these drugs. Given the current cost, they were, on average, willing to pay for the drugs only when the 5-year cardiovascular disease risk was as high as 35% (95% CI 31-38%) or even higher.

CONCLUSION

The public in China are significantly misinformed and considerably over estimate the risk of hypertension and the benefit of treatment. The public's willingness to pay for anti-hypertensive drugs is much lower than the current guidelines implicitly assume. The willingness to pay should be considered, along with other factors, when prescribing anti-hypertensive drugs to an individual patient or making hypertension guidelines for a population.

Rationale, design and patient baseline characteristics of OlmeSartan and calcium antagonists randomized (OSCAR) study: a study comparing the incidence of cardiovascular events between high-dose angiotensin II receptor blocker (ARB) monotherapy and combination therapy of ARB with calcium channel blocker in Japanese elderly high-risk hypertensive patients (ClinicalTrials. gov no. NCT00134160)

Higher doses of angiotensin II receptor blockers (ARBs) are expected to exert more protective effects against cardiovascular diseases. However, the significance of treatment of hypertension with high-dose ARB remains to be defined. The OlmeSartan and Calcium Antagonists Randomized (OSCAR) Study was designed to determine whether high-dose ARB monotherapy is superior to the combination therapy of ARB plus calcium channel blocker (CCB) in the prevention of cardiovascular morbidity/mortality in Japanese elderly high-risk hypertensive patients. The OSCAR study is a multicenter, active-controlled, two-arm parallel group comparison, using the prospective randomized open-blinded end-point method. In the 'Step 1' period, elderly hypertensive patients with diabetes or cardiovascular disease received monotherapy with ARB olmesartan medoxomil at a dose of 20 mg day(-1). If the target blood pressure control (less than 140/90 mm Hg) was not achieved by ARB monotherapy, the patients were randomized to receive either (1) the increased dose of olmesartan at 40 mg day(-1) (high-dose ARB monotherapy) or (2) the addition of a CCB (amlodipine or azelnidipine) to 20 mg day(-1) olmesartan (ARB plus CCB combination) in the 'Step 2' period. The follow-up duration will be 3 years. The primary end points will be the composite of fatal and non-fatal cardiovascular events, and death from any cause. Recruitment for the OSCAR study (around 1200 patients) was completed by the end of May 2007. The OSCAR study is the first large clinical trial comparing the efficacy of high-dose ARB monotherapy with that of an ARB plus CCB combination therapy in elderly high-risk hypertensive patients.

Renin-angiotensin-aldosterone system in the elderly: rational use of aliskiren in managing hypertension

The overall purpose of hypertension treatment is 2-fold. First, patients often have symptoms that are related to their high blood pressure and although subtle in many instances may be improved dramatically by blood pressure control. The main reason for blood pressure treatment, however, is to reduce the burden of cardiovascular complications and end organ damage related to the condition. This may be considered the ultimate goal of blood pressure treatment. In this respect, actual blood pressure measurements may be seen as surrogate end points as the organ protective effects of two antihypertensive agents may differ significantly even though their blood pressure lowering effects are similar. Thus beta-blockers, once seen as first-line treatment of hypertension for most patients, now are considered as third- or fourthline agents according to the latest NICE guidelines (National Institute for Health and Clinical Excellence, www.nice.org.uk/CG034). On the other hand, agents that inhibit the activity of the renin-angiotensin-aldosterone system (RAAS) system are being established as safe, effective and end organ protective in numerous clinical trials, resulting in their general acceptance as first-line treatment in most patients with stage 2 hypertension. This shift in emphasis from beta-blockers and thiazide diuretics is supported by numerous clinical trials and has proven safe and well tolerated by patients. The impact of this paradigm shift will have to be established in future long-term randomized clinical trials. The optimal combination treatment with respect to end organ protection has yet to be determined. Most combinations will include either a RAAS active agent and calcium channel blocker or two separate RAAS active agents working at different levels of the cascade. In this respect direct renin inhibitors and angiotensin receptor blockers seem particularly promising but the concept awaits evaluation in upcoming randomized clinical trials. Although safety data from the randomized clinical trials to date have been promising, we still lack data on the long-term effect of aliskiren on mortality and there still are patient groups where the safety of aliskiren is unexplored.

The evolution of systolic blood pressure as a strong predictor of cardiovascular risk and the effectiveness of fixed-dose ARB/CCB combinations in lowering levels of this preferential target

Elevated blood pressure is an important cardiovascular risk factor. Although targets for both diastolic blood pressure (DBP) and systolic blood pressure (SBP) are defined by current guidelines, DBP has historically taken precedence in hypertension management. However, there is strong evidence that SBP is superior to DBP as a predictor of cardiovascular events. Moreover, achieving control of SBP is assuming greater importance amongst an aging population. In spite of the growing recognition of the importance of SBP in reducing cardiovascular risk and the emphasis by current guidelines on SBP control, a substantial proportion of patients still fail to achieve SBP targets, and SBP control is achieved much less frequently than DBP control. Thus, new approaches to the management of hypertension are required in order to control SBP and minimize cardiovascular risk. Fixed-dose combination (FDC) therapy is an approach that offers the advantages of multiple drug administration and a reduction in regimen complexity that favors compliance. We have reviewed the latest evidence demonstrating the efficacy in targeting SBP of the most recent FDC products; combinations of the calcium channel blocker (CCB), amlodipine, with angiotensin receptor blockers (ARBs), valsartan or olmesartan. In addition, results from studies with new classes of agent are outlined.

Principal results of the Japanese trial to assess optimal systolic blood pressure in elderly hypertensive patients (JATOS)

The benefits of lowering a systolic blood pressure below 140 mmHg in elderly hypertension remain controversial. This study is a prospective, randomized, open-label study with blinded assessment of endpoints to compare the 2-year effect of strict treatment to maintain systolic blood pressure below 140 mmHg with that of mild treatment to maintain systolic blood pressure below 160 but at or above 140 mmHg in elderly hypertensive patients. Patients with essential hypertension (65-85 years old, with a pretreatment systolic blood pressure of above 160 mmHg) were randomly assigned to receive strict treatment (n=2,212) or mild treatment (n=2,206). The baseline drug was efonidipine hydrochloride, a long-acting calcium antagonist. The primary endpoint was the combined incidence of cardiovascular disease and renal failure, and the secondary endpoints were total deaths and any safety problems. Although final blood pressures (systolic/diastolic) were significantly lower in the strict-treatment group compared with the mild-treatment group (135.9/74.8 vs. 145.6/78.1 mmHg; p<0.001), the incidence of the primary endpoint was similar in the two groups (86 patients in each group; p=0.99). Total deaths were 54 in the strict-treatment group vs. 42 in the mild-treatment group (p=0.22), and treatment was withdrawn because of adverse events in 36 patients in each group (p=0.99). An interaction between age and treatment for the primary endpoints (p=0.03) was seen. Complex clinical features associated with aging seem to have obscured the difference in effect between the two treatments. Further studies are needed to assess the optimal treatment strategy for hypertension in the elderly.

Increased risk of exacerbating gastrointestinal disease among elderly patients following treatment with calcium channel blockers

BACKGROUND AND OBJECTIVE

Calcium channel blockers (CCBs) have been widely used for the treatment of hypertension and angina pectoris. It is presumed that CCBs decrease the lower esophageal sphincter pressure and as a result, the risk of gastrointestinal disease may be increased. Since the prevalence of gastrointestinal diseases has increased in elderly patients, it is possible that treatment with CCBs may have contributed to this increase. Therefore, we considered that the risk of exacerbating gastrointestinal disease among elderly patients by CCBs can be estimated by using the prescription ratio of antisecretory drugs as an outcome.

METHOD

We hypothesized that patients who are prescribed CCBs would increase the use of antisecretory drugs involving H(2)-receptor antagonists and proton pump inhibitors (PPIs). From January 2001 to December 2005, a dynamic retrospective cohort study was performed at three community pharmacies in Nagasaki city, Japan, to assess the use of antisecretory drugs following treatment with CCBs among elderly patients. The correlation of initiation of antisecretory drugs treatment to maintenance therapy with PPIs was determined by the Cox proportional hazards model.

RESULTS

The proposed study includes 303 patients prescribed CCBs and 258 controls. During the study period, 138 patients prescribed CCBs and 66 controls were initiated by giving antisecretory drugs; the hazard ratio was 1.40 (95% confidence interval 1.21-1.63). Eighty two patients taking CCBs and 32 controls were initiated by the maintenance therapy with PPIs; the hazard ratio was 1.48 (95% confidence interval 1.21-1.83).

CONCLUSION

Patients who simultaneously initiated the use of antisecretory drugs with CCBs could not be found. Therefore, antisecretory drugs have not been used to prevent the gastrointestinal diseases caused by CCBs. The results obtained in this study suggest that the risk of gastrointestinal disease could be increased by long-term treatment with CCBs for elderly patients.

Fixed combinations in the management of hypertension: perspectives on lercanidipine-enalapril

Although achieving blood pressure (BP) control is critical to improve cardiovascular prognosis in hypertensive patients, many of them fail to achieve BP goals. The majority of hypertensive patients need more than one antihypertensive agent to attain BP targets. Combination therapy is required when monotherapy fails to attain BP objectives and as a first-line treatment in certain situations, such as markedly elevated BP values, when lower targets are required in high or very high cardiovascular risk patients. The advantages of combination therapy are well documented, with an increased antihypertensive efficacy as a result of the simultaneous inhibition of different mechanisms of action and with a lesser incidence of adverse events, because of the possible compensatory responses and the lower doses used. Calcium channel blockers are effective drugs in the treatment of hypertension. The efficacy of lercanidipine has been evaluated in several noncomparative and in comparative studies showing a great efficacy with a good tolerability. On the other hand, the inhibition of the renin-angiotensin system appears to be very beneficial in the treatment of patients with hypertension. Enalapril is an effective and well tolerated angiotensin converting enzyme inhibitor. Although there are several fixed-combination drugs, the combination lercanidipine plus enalapril appears to be one of the most promising therapies in the treatment of hypertension. The aim of this manuscript is to update the published data about the efficacy and safety of this fixed combination.

Review of nifedipine GITS in the treatment of high risk patients with coronary artery disease and hypertension

Nifedipine is a dihydropyridine calcium-channel blocker (CCB) introduced approximately 30 years ago for the prophylaxis of angina symptoms, and then later utilized as an anti-hypertensive agent. In the 1990s, several meta-analyses and a case-control study were published which raised concern regarding increased mortality and increased risk for myocardial infarction with short-acting nifedipine. Further evaluation of these meta-analyses and case control study underscores some important limitations and the need to further elucidate the role of this class of medications in high-risk patients. Until 2000, there was a paucity of data on the long-term effects as well as the long-term outcomes of CCBs in the treatment of stable coronary disease or in patients with manifestations of the disease such as hypertension or angina. While it has been well established that nifedipine and other dihydropyridines lower blood pressure and improve symptoms of angina, several studies were designed to evaluate the effect of dihydropyridines on "hard" outcomes, specifically cardiovascular and cerebrovascular events. In this review, we describe the clinical studies evaluating the use of nifedipine when compared to placebo as well as other anti-hypertensive therapies in an attempt to identify the most appropriate place in therapy for this class of medications and to further clarify its utilization in high-risk patients.

[Hypertension in the elderly population]

The prevalence of essential hypertension in the Spanish population aged more than 60 years old is greater than 65%, mainly due to the high prevalence of elevated systolic pressure. Essential hypertension is known to be the most important risk factor for the development of cardiovascular disease, which continues to be the leading cause of death among adults in the developed world. Several randomized, placebo-controlled clinical trials have demonstrated the beneficial effects of antihypertensive treatment in hypertensive elderly people. However, the management of high blood pressure in the elderly population can be difficult due to a series of factors in this group such as altered pharmacokinetics, comorbidity, and polypharmacy. In addition, although there is recent evidence of the benefit of antihypertensive treatment in the oldest old (> 85 years), comprehensive geriatric assessment and individualized treatment should be applied in daily clinical practice.

Meta-analysis of continuous outcomes combining individual patient data and aggregate data

Meta-analysis of individual patient data (IPD) is the gold-standard for synthesizing evidence across clinical studies. However, for some studies IPD may not be available and only aggregate data (AD), such as a treatment effect estimate and its standard error, may be obtained. In this situation, methods for combining IPD and AD are important to utilize all the available evidence. In this paper, we develop and assess a range of statistical methods for combining IPD and AD in meta-analysis of continuous outcomes from randomized controlled trials. The methods take either a one-step or a two-step approach. The latter is simple, with IPD reduced to AD so that standard AD meta-analysis techniques can be employed. The one-step approach is more complex but offers a flexible framework to include both patient-level and trial-level parameters. It uses a dummy variable to distinguish IPD trials from AD trials and to constrain which parameters the AD trials estimate. We show that this is important when assessing how patient-level covariates modify treatment effect, as aggregate-level relationships across trials are subject to ecological bias and confounding. We thus develop models to separate within-trial and across-trials treatment-covariate interactions; this ensures that only IPD trials estimate the former, whilst both IPD and AD trials estimate the latter in addition to the pooled treatment effect and any between-study heterogeneity. Extension to multiple correlated outcomes is also considered. Ten IPD trials in hypertension, with blood pressure the continuous outcome of interest, are used to assess the models and identify the benefits of utilizing AD alongside IPD.

The study of aortic stiffness in different hypertension subtypes in dialysis patients

The aim of this study was to validate whether differences in aortic stiffness are responsible for the differences in cardiovascular mortality among hypertension subtypes. Twenty hundred and fifty continuous ambulatory peritoneal dialysis patients were included in the present study. They were classified into four groups: normotensives (n=92) with systolic blood pressure (SBP) <140 mmHg and diastolic blood pressure (DBP) <90 mmHg; isolated systolic hypertensives (ISH, n=84) with SBP > or =140 mmHg and DBP <90 mmHg; isolated diastolic hypertensives (IDH, n=21) with SBP <140 mmHg and DBP > or =90 mmHg; and systolic-diastolic hypertensives (SDH, n=53) with SBP > or =140 mmHg and DBP > or =90 mmHg. Aortic stiffness was assessed by pulse pressure, central pressure parameters and pulse wave velocity. The IDH group had more male patients and a lower mean age than the other groups. The percentage of diabetes in the ISH group was higher than that in the other groups. The comparisons of aortic stiffness showed that the ISH and SDH groups had higher aortic stiffness than the normotension and IDH groups. The aortic stiffness in the ISH group was also higher than that in the SDH group, but there was no significant difference in aortic stiffness between the normotension and IDH groups. In conclusion, this study showed that aortic stiffness was significantly different among different hypertension subtypes, which might be an underlying cause of the differences in cardiovascular mortality among the hypertension subtypes.

Stepwise increase in the prevalence of isolated systolic hypertension with the stages of chronic kidney disease

BACKGROUND

Hypertension is common in patients with chronic kidney disease (CKD), and isolated systolic hypertension (ISH) accounts for most patients with inadequate blood pressure (BP) control. However, it remains unclear whether the prevalence of ISH would increase with the advancement of CKD.

METHODS

CKD patients of stages 3, 4 and 5 were recruited (n = 324). Based on office systolic BP (SBP) and diastolic BP (DBP), they were classified into any of the four hypertensive subtypes: normotension (SBP/DBP <140/90 mmHg), isolated diastolic hypertension (IDH, SBP <140 mmHg and DBP >or=90 mmHg), ISH (SBP >or=140 mmHg and DBP <90 mmHg) and systolic-diastolic hypertension (SDH, SBP/DBP >or=140/90 mmHg).

RESULTS

The control rate was 45.7% at stage 3, which decreased with the advancement of CKD (control rate was 51.9%, 40.4% and 38.6% in stage 3, 4 and 5, respectively; P < 0.05). The prevalence of IDH changed from 5.0% to 5.3% and 0% from stage 3 to 4 and 5, while there was no significant change in the prevalence of SDH (15.0%, 14.9% and 15.7% at stage 3, 4 and 5, respectively). There was a stepwise increase in the prevalence of ISH with the stages of CKD (it was 28.1%, 39.4% and 45.7% in stage 3, 4 and 5, respectively). Logistic regression showed that age and CKD stages [compared with stage 3, stage 4 and 5 had 2.57 (95% CI 1.04-6.33) and 3.68 (95% CI 1.09-12.47) folds higher risk to develop ISH, respectively] were independent predictors of ISH.

CONCLUSION

The prevalence of ISH increased correspondingly with advanced stages of CKD, which may partially contribute to the increased cardiovascular mortality during the progress of CKD.

Aggressive blood pressure control and stroke prevention: role of calcium channel blockers

Cerebrovascular disease is a major cause of morbidity and mortality worldwide and its prevalence is expected to increase as a result of projected demographic trends. Stroke is one of the leading causes of disability and death of over 30 million people each year worldwide. Hypertension is the most important modifiable risk factor for stroke. Recent data indicate that treatment with antihypertensive drugs reduces the incidence of all strokes in men (by 34%), women (by 38%), the elderly (by 36%), including those older than 80 years (by 34%), younger persons, those with systolic and diastolic hypertension, persons with isolated systolic hypertension, and those with a history of stroke or transient ischemic attack (by 28%). Furthermore, several large, prospective, randomized, clinical outcome trials have shown that calcium channel blockers (CCBs) are effective and safe antihypertensive drugs compared with placebo and reduce the cardiovascular morbidity and mortality of treated patients. Moreover, when CCBs were compared with conventional antihypertensive drugs they demonstrated similar blood pressure-lowering effects and similar reductions in cardiovascular morbidity and mortality, with the exception of a higher incidence of heart failure and fatal myocardial infarction in some studies. Considering all the evidence available today, however, these drugs should be considered safe for the treatment of the uncomplicated hypertensive patient in combination with other drugs. They can also be used as first-line therapy for older, stroke-prone hypertensive patients. The aim of this review is to summarize the role of CCBs in the prevention of stroke.

Nitric oxide in the kidney : its physiological role and pathophysiological implications

Nitric oxide has been implicated in many physiologic processes that influence both acute and long-term control of kidney function. Its net effect in the kidney is to promote natriuresis and diuresis, contributing to adaptation to variations of dietary salt intake and maintenance of normal blood pressure. A pretreatment with nitric oxide donors or L-arginine may prevent the ischemic acute renal injury. In chronic kidney diseases, the systolic blood pressure is correlated with the plasma level of asymmetric dimethylarginine, an endogenous inhibitor of nitric oxide synthase. A reduced production and biological action of nitric oxide is associated with an elevation of arterial pressure, and conversely, an exaggerated activity may represent a compensatory mechanism to mitigate the hypertension.

Thresholds of risk factors for ischemic stroke in type 2 diabetic patients with and without albuminuria: a non-linear approach

OBJECTIVES

Multiple risk factors in type 2 diabetes may explain their high risk for ischemic stroke (IS). However, it remains unknown whether these risk factors exhibit threshold characteristics and whether these relationships are influenced by albuminuria. The study aims to investigate whether risk factors exhibit any albuminuria specific threshold for IS.

PATIENTS AND METHODS

This is a prospective cohort study with 6969 Chinese type 2 diabetic patients without history of stroke after a median follow-up of 5.36 years. We identified thresholds of risk factors for IS using hazard ratio plots followed by confirmation using traditional Cox regression analysis.

RESULTS

In the non-albuminuric group (n=4008), IS risk started to increase rapidly at a body mass index threshold of 24 kg/m(2). The risk of IS declined with increasing blood hemoglobin reaching a threshold value of 14 g/dl. Using these threshold values as cutoff point, body mass index > or =24 kg/m(2) and hemoglobin <14 g/dl were associated with 2-fold increased risk of IS in these subjects. In the albuminuric group (n=2961). IS risk started to increase rapidly from a systolic blood pressure threshold of 135 mmHg and declined with increasing estimated glomerular filtration rate (eGFR) reaching a trough of 115 ml/min per 1.73 m(2). Using these values as cutoff points, patients with systolic blood pressure > or =135 mmHg and eGFR <115 ml/min per 1.73 m(2) had 2-fold increased risk of IS.

CONCLUSION

In type 2 diabetic patients, body mass index, hemoglobin, systolic blood pressure and eGFR exhibit different risk relationships and thresholds for IS contingent upon presence or absence of albuminuria.

Efficacy and safety of two treatment combinations of hypertension in very elderly patients

The study compared valsartan/amlodipine combination with irbesartan/hydrochlorothiazide (HCTZ) combination in very elderly hypertensives. After a 4-week placebo period, 94 hypertensives, aged 75-89 years were randomized to valsartan 160mg/amlodipine 5mg or irbesartan 300mg/HCTZ 12.5mg for 24 weeks according to a prospective, parallel group study. After 4 weeks amlodipine or HCTZ was doubled in non-responders. Patients were checked every 4 weeks. At each visit clinical sitting, lying and standing blood pressure (BP), systolic BP (SBP) and diastolic BP (DBP) were evaluated, and an electrocardiogram was performed. At the end of the placebo period and of the treatment period a non-invasive 24-h ambulatory BP monitoring (ABPM) was performed and electrolytes and uric acid were evaluated. Both combinations significantly reduced ambulatory BP. In the valsartan/amlodipine group the mean reduction (-29.9/-15.6 for 24h, -28.6/-14.5mmHg for day-time and -26.2/-17.4mmHg for night-time SBP/DBP) was similar to that of the irbesartan/HCTZ group (-29.6/-15.4 for 24h, -29.3/-14.9mmHg for day-time and -25.4/-16.9mmHg for night-time SBP/DBP). Both combinations significantly reduced clinical sitting and lying BP values with no difference between treatments. BP changes from lying to standing position were significantly greater in the irbesartan/HCTZ group (-17.2/-9.1mmHg) than in the valsartan/amlodipine group (-10.1/-1.9mmHg, p<0.05 for SBP and p<0.01 for DBP vs. irbesartan/HCTZ). Potassium significantly decreased and uric acid significantly increased (-0.4mmol/l, p<0.05 and +0.5mg/dl, p<0.05 vs. baseline, respectively) only in the irbesartan/HCTZ group. In conclusion, both combinations were similarly effective in reducing ambulatory and clinical BP in very elderly hypertensives. However, valsartan/amlodipine offered some advantages in terms of less pronounced BP orthostatic changes and absence of metabolic adverse effects.

Prevention of cardiovascular events by treating hypertension in older adults: an evidence-based approach

Hypertension in older adults is not well controlled in clinical practice. Isolated systolic hypertension is often more difficult to manage. A systematic PubMed search was conducted to look for evidence showing benefits of lowering blood pressure (BP) in older hypertensive adults. Lowering BP in these individuals significantly reduces the risk of coronary artery disease, stroke, and cardiovascular and all-cause mortality. Based on trial evidence, a low-dose diuretic should be considered the most appropriate first-step treatment for preventing cardiovascular morbidity and mortality. Therapy with >1 medication is often necessary to reduce BP in these patients. There is unequivocal evidence that cardiovascular events can be prevented in older adults, even those older than 80 years, by treating hypertension.

Effective management of hypertension with dihydropyridine calcium channel blocker-based combination therapy in patients at high cardiovascular risk

The increasing prevalence of hypertension, owing to modern lifestyles and the increasing elderly population, is contributing to the global burden of cardiovascular (CV) disease. Although effective antihypertensive therapies are available, blood pressure (BP) is generally poorly controlled. In addition, the full benefits of antihypertensive therapy can only be realised when target BP is achieved. International guidelines and clinical trial evidence support the use of combination therapy to manage hypertension. In high-risk patients, such as those with coronary artery disease, diabetes and renal dysfunction, BP targets are lower and there is a need for intensive management with combination therapy to control BP and provide additional CV risk reduction benefits. Combinations of antihypertensive agents with different but complementary modes of action improve BP control and may also provide vascular-protective effects. Calcium channel blockers (CCBs) have been shown to be effective in combination with a range of antihypertensive drugs and in different patient populations. As part of a first-line combination strategy, CCBs can provide CV benefits beyond BP control, even in patients at increased CV risk. Benefits include protection against end-organ damage and serious CV events. Indeed, in major intervention trials, these benefits have already been clearly demonstrated. Ongoing studies will provide further data to support the clinical benefits of combination therapy as a first-line treatment approach. Implementation of this approach in clinical practice, together with adherence to global hypertension management guidelines will help ensure patients achieve and sustain BP targets, and reduce the risk of CV events.

Optimal drug treatment of systolic hypertension in the elderly

Approximately two-thirds of the elderly population has hypertension, mainly of the isolated systolic hypertension (ISH) type. However, while large-scale, randomized controlled intervention trials have demonstrated that treatment of ISH reduces rates of total mortality, cardiovascular mortality and stroke in older hypertensives, control of ISH in the elderly remains poor. The aim of this review of drug treatment of ISH in the elderly is to provide a succinct, practical and clinically orientated guide that summarizes international recommendations and practices with special emphasis on newer approaches. Knowledge of pathophysiological changes in older subjects (decreased elastic artery compliance, reduced plasma renin activity, increased salt sensitivity) and evidence from epidemiological surveys and randomized controlled trials give clear clues that thiazide(-like) diuretics and long-acting dihydropyridine calcium channel antagonists are the drugs of choice in the treatment of ISH. Thus, based on this evidence, American, European and international guidelines for hypertension management still offer the best available recommendations for optimal treatment of ISH in the elderly. Newer combination treatments, especially the fixed combination of a dihydropyridine calcium channel antagonist and an ACE inhibitor, have valuable benefits in terms of efficacy and tolerability. Use of nitrates added to other antihypertensive medications can provide the practising physician with a further unconventional therapeutic strategy.

The metabolic syndrome in East Asians

The metabolic syndrome is an emerging epidemic in developing nations, including East Asian countries such as China, Japan, and Korea. Studies examining the metabolic syndrome have used different definitions, with prevalence often highly dependent on the cut points for abdominal obesity utilized, which have been recommended by the International Diabetes Federation to be lower than standards used in Caucasians and other ethnic groups. Prevalence rates have generally varied from 8% to 13% in men and 2% to 18% in women, depending on ethnic group and definition used, and are consistently lower than most Western Caucasian populations. While recent dramatic changes in lifestyle from Westernization of dietary habits and reduced physical activity present challenges, an emphasis on healthful lifestyle changes remains the cornerstone for metabolic syndrome management. In addition, clinical management focusing on control of obesity, elevated blood pressure, dyslipidemia, and hyperglycemia, with consideration of pharmacologic therapy issues unique to certain Asian populations, remains important for reducing associated cardiometabolic risks.

Systolic hypertension in the elderly: addressing an unmet need

Systolic hypertension is a major public health issue in the elderly and is often under-recognized and under-treated. The concept that systolic blood pressure increases with age should be considered a pathophysiologic concept. Aging of the cardiovascular system is accompanied by endothelial dysfunction, activation of the renin-angiotensin system and, consequently, vascular remodeling. This process leads to an increase in large artery stiffness and an increase in arterial wave reflections to the heart. These processes in daily clinical practice translate to an increase in systolic blood pressure, which is associated with increased cardiovascular morbidity and mortality. Evidence-based medicine recommendations to treat systolic hypertension in the elderly are based on landmark and recent clinical trials, which clearly demonstrated that treatment of isolated systolic hypertension is associated with significant decreases in cardiovascular morbidity and mortality. However, treatment of systolic hypertension in older adults remains disappointing because therapeutic goals often are not reached. Therefore, emphasis should be placed on the treatment of systolic hypertension in the elderly, and there is need for more effective, individualized antihypertensive therapy.