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 older patients: an updated look at the role of calcium antagonists

Hypertension is common in adults aged 60 years or older. Apart from age, hypertension is the most powerful predictor of cardiovascular end-organ damage and its associated morbidity and mortality. Although diastolic blood pressure is regarded as an important risk factor, it is now clear that systolic blood pressure, especially prevalent among older adults, is a better predictor of cardiovascular morbidity and mortality. Fewer than 30% of hypertensive patients have blood pressure levels controlled to <140/90 mm Hg as recommended by current guidelines. Controlled trials have demonstrated the benefits of lowering blood pressure for all hypertensive individuals, including those aged 65 years or older. Calcium antagonists of the dihydropyridine subclass, which include nifedipine, amlodipine, felodipine, and nitrendipine, as well as other drug classes, are potent antihypertensive agents that may be suitable for treatment of hypertension in older adults. However, as with all antihypertensive agents, adverse effects may limit their use; peripheral edema is particularly troublesome for dihydropyridines. Newer dihydropyridine calcium antagonists expected to be approved for use soon, including lercanidipine and lacidipine, have been associated with efficacy comparable to currently available calcium antagonists but with a lower incidence of adverse effects, especially ankle edema. Antihypertensive agents with improved tolerability profiles offer the potential for improved blood pressure control.

Blood pressure and lipid lowering in the prevention of stroke: a note to neurologists

Stroke is the leading cause of adult disability and dependency in western society. Despite the determined efforts of basic science and clinical investigators, neuroprotective therapies for acute stroke have yet to be realised. Stroke prevention, therefore, remains the key route for reducing morbidity and mortality. Hypertension and hypercholesterolaemia are the most important modifiable risk factors for stroke. Several recent landmark studies have shown that lipid lowering with statins can reduce the risk of ischaemic stroke, as well as coronary heart disease. In addition, clinical trials evaluating the effects of blood pressure lowering have shown that antihypertensive agents such as angiotensin-converting enzyme (ACE) inhibitors, calcium channel blockers (CCBs) and angiotensin II receptor antagonists can reduce stroke risk. Accumulating evidence suggests certain antihypertensive agents such as CCBs might also prevent the formation and progression of carotid atheroma, independently of their blood-pressure-lowering effects. It follows that rigorous identification and targeting of high- risk or stroke-prone individuals for blood pressure and lipid-lowering interventions should be of practical importance to all physicians involved in the management of stroke.

Trials in isolated systolic hypertension: an update

Isolated systolic hypertension (ISH) has proved to be a powerful predisposing factor for cardiovascular diseases in the elderly. Recent placebo-controlled interventional trials such as the Systolic Hypertension in the Elderly Program (SHEP), the Systolic Hypertension in Europe (Syst-Eur), and the Systolic Hypertension in China (Syst-China) showed that the lowering of systolic blood pressure using a diuretic- or a calcium antagonist-based treatment is associated with a decrease in cardiovascular events. Antihypertensive therapy was found especially effective in preventing stroke in the elderly with ISH. A slowing in the progression of dementia was observed in patients randomized to a calcium antagonist-based treatment. Patients at high cardiovascular risk such as those with diabetes benefited the most from treatment. In another trial performed in patients with left ventricular hypertrophy (Losartan Intervention For Endpoint Reduction ), a subset of patients had ISH. In those patients, an angiotensin II antagonist-based treatment was superior to a b-blocker-based treatment in preventing cardiovascular complications. The experience accumulated in patients with ISH showed that combination therapy is often required to control blood pressure. Overall, the evidence available today indicates that pharmacologic treatment of ISH markedly improves the outcome of elderly patients.

Has the role of calcium channel blockers in treating hypertension finally been defined?

Several large, prospective, randomized, clinical outcome trials have shown that calcium channel blockers are effective and safe antihypertensive drugs compared with placebo and reduce the cardiovascular morbidity and mortality of treated patients. In other studies, when 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. However, considering all the evidence available today, 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. In addition, when a calcium channel blocker is indicated for better blood pressure control, its use should not be withheld for safety concerns.

Drug therapy of heart failure in the elderly

Heart failure is a disorder that predominantly affects older adults, with more than 50% of heart failure hospitalizations occurring in persons over 75 years of age. Unfortunately, most of the major heart failure clinical trials have targeted middle-aged patients with systolic heart failure, and the applicability of these studies to elderly patients, particularly those with preserved left ventricular systolic function, remains uncertain. In this paper, current data on the pharmacotherapy of heart failure in older adults are reviewed, recommended approaches to managing systolic and diastolic heart failure are outlined, and the importance of preventive measures is emphasized.

Cardiovascular prevention and blood pressure reduction: a quantitative overview updated until 1 March 2003

BACKGROUND

In a meta-analysis published in October 2001, 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 pressure accounted for most differences in outcome.

OBJECTIVE

To test whether our previous conclusions would hold, we updated our quantitative overview with new information from 14 clinical trials presented before 1 March 2003.

METHODS

To compare new and old antihypertensive drugs, we computed pooled odds ratios from stratified 2 x 2 contingency tables. If Zelen's test of heterogeneity was significant, we used a random effects model. In a meta-regression analysis, we correlated odds ratios with corresponding between-group differences in systolic pressure. We then contrasted observed odds ratios with those predicted from gradients in systolic pressure.

MAIN OUTCOMES

Differences in achieved systolic blood pressure and incidence of total and cardiovascular mortality, cardiovascular events, stroke, myocardial infarction and heart failure. NEW VERSUS OLD DRUGS: In 15 trials, 120 574 hypertensive patients were randomized to old drugs (diuretics or beta-blockers) or new agents [calcium-channel blockers, alpha-blockers, angiotensin-converting enzyme (ACE) inhibitors or angiotensin type-1 receptor (AR1) blockers]. Old and new drugs provided similar protection against total and cardiovascular mortality and fatal plus non-fatal myocardial infarction. Calcium-channel blockers, including (-8%, P = 0.07) or excluding verapamil (-10%, P = 0.02), as well as AR1 blockers (-24%, P = 0.0002) resulted in better stroke prevention than did the old drugs, whereas the opposite trend was observed for ACE inhibitors (+10%, P = 0.03). The risk of heart failure was higher (P < 0.0001) on calcium-channel blockers (+33%) and alpha-blockers (+102%) than on conventional therapy involving diuretics. META-REGRESSION: Between-group differences in achieved systolic pressure ranged from 0.1 to 3.2 mmHg in seven actively controlled trials (73 237 patients), and from 2.1 to 22.1 mmHg in seven studies comparing varying intensities of blood pressure lowering (11 128 patients). For these 14 new trials, we predicted outcome from achieved systolic blood pressure using our previously published meta-regression models based on 30 trials with 149 407 patients. In general, predicted and observed odds ratios were similar. Larger reductions in systolic pressure (weighted mean 1.8 mmHg) in two trials accounted for the advantage of AR1 blockers over conventional therapy in the prevention of stroke. Only for cardiovascular mortality in very old patients (P = 0.02) and for cardiovascular events and myocardial infarction in old Australians (P < 0.05), the observed odds ratios deviated from our predictions based on the gradients in systolic blood pressure.

INTERPRETATION

The hypothesis that new antihypertensive drugs, such as calcium-channel blockers, alpha-blockers, ACE inhibitors or AR1 blockers might influence cardiovascular prognosis over and beyond their antihypertensive effects remains unproven. The finding that blood pressure differences largely accounted for cardiovascular outcome emphasizes the desirability of tight blood pressure control. However, the level to which blood pressure must be lowered to achieve maximal benefit remains currently unknown.

Restoration of nocturnal dip in blood pressure is associated with improvement in left ventricular ejection fraction. A 1-year clinical study comparing the effects of amlodipine and nifedipine retard on ambulatory blood pressure and left ventricular systolic function in Chinese hypertensive type 2 diabetic patients

We assessed the effects of amlodipine and nifedipine retard on 24-h blood pressure (BP) control, nocturnal fall in BP and their significance on left ventricular systolic functions in 54 Chinese hypertensive type 2 diabetic patients. Patients being recruited were openly randomised to amlodipine or nifedipine retard. Ambulatory 24-h BP and echocardiogram (in 42 patients) were measured before and 1 year after treatment. At the end of study, there was 17% reduction in systolic BP; 17% reduction in diastolic BP and 12% reduction in mean arterial pressure (MAP) (no difference between amlodipine and nifedipine). Of the 42 subjects underwent echocardiograms, eight became 'new-dippers' at the end of study (non-dippers before treatment and restored nocturnal fall of MAP> or =10% after treatment). The other 34 patients were either non-dippers before and after treatment (n=27); dippers before and after treatment (n=3) or dippers before treatment and non-dippers after treatment (n=4). The eight 'new-dippers' had improved ejection fraction (69.6+/-7.2 to 75.8+/-7.4%, P<0.05) and increased left ventricular diastolic diameter (43.7+/-7.9 to 47.9+/-8.8 mm, P<0.05) after the 1-year treatment of calcium antagonist. Compared to the other 34 subjects, the eight 'new-dippers' showed significant improvement in ejection fraction (9.4+/-10.9 vs. -1.2+/-11.8%, P<0.05). In conclusion, both amlodipine and nifedipine retard are effective in controlling the 24-h BP in Chinese hypertensive type 2 diabetic patients. For those who have restored nocturnal dip in BP have significantly increased left ventricular systolic ejection fraction after 1-year treatment of long acting calcium antagonists. The clinical significance and underlying mechanisms require further studies.

The economic impact of hypertension

High blood pressure is the most common chronic medical problem prompting visits to primary health care providers, yet it is estimated that only 34% of the 50 million American adults with hypertension have their blood pressure controlled to a level of <140/90 mm Hg. Thus, about two thirds of Americans with hypertension are at increased risk for cardiovascular events. The medical, economic, and human costs of untreated and inadequately controlled high blood pressure are enormous. Adequate management of hypertension can be hampered by inadequacies in the diagnosis, treatment, and/or control of high blood pressure. Health care providers face many obstacles to achieving blood pressure control among their patients, including a limited ability to adequately lower blood pressure with monotherapy and a typical reluctance to increase therapy (either in dose or number of medications) to achieve blood pressure goals. Patients also face important challenges in adhering to multidrug regimens and accepting the need for therapeutic lifestyle changes. Nonetheless, the achievement of blood pressure goals is possible, and, most importantly, lowering blood pressure significantly reduces cardiovascular morbidity and mortality, as proved in clinical trials. The medical and human costs of treating preventable conditions such as stroke, heart failure, and end-stage renal disease can be reduced by antihypertensive treatment. The recurrent and chronic morbidities associated with hypertension are costly to treat. Pharmacotherapy for hypertension therefore offers a substantial potential for cost savings. Pharmacoeconomic analyses regarding antihypertensive drug therapies, their costs, and the relevant reductions in health care expenditures are a useful framework for optimizing current strategies for hypertension management.

What is the most important component of blood pressure: systolic, diastolic or pulse pressure?

PURPOSE OF REVIEW

Diastolic blood pressure has traditionally been considered the most important component of blood pressure and the primary target of antihypertensive therapy. However, over 30 years ago important epidemiological studies pointed out the importance of systolic blood pressure, and research during the 1990s has strengthened this view. Unlike diastolic blood pressure, systolic blood pressure increases progressively with age, and in the ageing societies elevated systolic pressure is the most common form of hypertension. The characteristic changes of systolic and diastolic blood pressure with age lead to increases in pulse pressure (systolic minus diastolic), which has emerged as a new, potentially independent risk factor. In this review we compare the relative importance of various blood pressure components.

RECENT FINDINGS

Generally, in studies in which readings of systolic and diastolic blood pressure have been compared, systolic blood pressure has been a better predictor of risk. Moreover, isolated systolic hypertension predicts risk better than isolated diastolic hypertension, and the treatment of both isolated systolic hypertension and combined hypertension has reduced cardiovascular events. There are no treatment studies of isolated diastolic hypertension. Pulse pressure reflects stiffening of large arteries and is associated with several cardiovascular risk factors. Pulse pressure also predicts events in epidemiologic studies, but elucidation of an independent role is hampered by the close correlation between pulse pressure and systolic blood pressure.

SUMMARY

Epidemiological and treatment studies suggest that systolic blood pressure should be the primary target of antihypertensive therapy, although consideration of systolic and diastolic pressure together improves risk prediction. The greatest practical concern at the moment is the undertreatment of hypertension, especially systolic, and total cardiovascular risk.

Uncontrolled hypertension as a risk for coronary artery disease: patient characteristics and the role of physician intervention

Hypertension is the most widely treated cardiovascular risk factor, and there is clear evidence of the efficacy of treating systolic and diastolic blood pressure with existing antihypertensive agents in reducing stroke and cardiac disease. However, only about 25% of the US population has blood pressure controlled to at least 140 mm Hg systolic and 90 mm Hg diastolic. Hypertension control is a complex function of patient and physician behavior. Although poor hypertension control has historically been attributed to lack of health insurance or low utilization of available services, recently published analyses of national survey data and local physician and community samples suggest that physicians have a permissive attitude toward isolated mild systolic blood pressure elevations in the range of 140 to 160 mm Hg. The great majority of participants in health surveys report seeing a physician at least two times per year, and several investigators have documented that physicians are unlikely to increase treatment intensity for systolic elevations alone. Physician inaction toward elevated systolic blood pressure may be due to a reluctance to prescribe multiple drugs and/or lack of belief in the benefits of aggressive treatment to lower systolic blood pressure below 140 mm Hg.

Azelnidipine and amlodipine: a comparison of their pharmacokinetics and effects on ambulatory blood pressure

We objected: 1) To compare the effects of azelnidipine and amlodipine on 24-h blood pressure; 2) To monitor the plasma concentration vs. the time profile in order to assess the association between pharmacokinetics and hypotensive activity after administration of either drug for 6 weeks. Blood pressure and pulse rate were measured by 24-h monitoring with a portable automatic monitor in a randomized double-blind study of 46 patients with essential hypertension. Azelnidipine 16 mg (23 patients) or amlodipine 5 mg (23 patients) was administered once daily for 6 weeks. Pharmacokinetics were analyzed after the last dose was taken. Both drugs showed similar effects on the office blood pressure and pulse rate. During 24-h monitoring, both drugs caused a decrease in systolic blood pressure of 13 mmHg and had a similar hypotensive profile during the daytime period (07:00-21:30). The pulse rate decreased by 2 beats/min in the azelnidipine group, whereas it significantly increased by 4 beats/min in the amlodipine group. Similar trends in the blood pressure and pulse rate were observed during the nighttime (22:00-6:30) and over 24 h. Excessive blood pressure reduction during the nighttime was not seen in either group. The pharmacokinetic results indicated that the plasma half-life (t1/2) of amlodipine was 38.5 +/- 19.8 h and that of azelnidipine was 8.68 +/- 1.33 h. Despite this difference in pharmacokinetics, the hypotensive effects of amlodipine and azelnidipine were similar throughout the 24-h administration period.

Isolated systolic hypertension: data on a cohort of young subjects from a French working population (IHPAF)

Elderly patients with isolated systolic hypertension (ISH)--systolic blood pressure (SBP) > or =140 mmHg and diastolic blood pressure (DBP) <90 mmHg--have increased mortality and morbidity. The aim was to study the incidence of ISH in a younger population of between 15 and 60 years of age, and to measure pulse pressure (PP), mean arterial pressure (MAP) and heart rate (HR) in these subjects. The study population consisted of 27 783 subjects, aged 15-60 years, untreated for hypertension (HT) from a cohort of employees formed to study the incidence of HT in the French working population (AIHFP). BP and HR were measured with a validated, automatic device after 5, 6 and 7 min at rest. The prevalence of ISH was 6.9% in men, 2.3% in women. This prevalence was over 5% in young men and increased at 40-44 years; it was negligible in young women, but increased at 50-54 years to about 10% (ie to the same level as in men of the same age): PP in subjects with ISH (46.9 mmHg) was significantly higher than in the normotensive group (NT-40.9 mmHg); it was comparable in both young men (65.5 mmHg) and older men (66 mmHg); it was higher in men (63.1 mmHg) than in women (61.5 mmHg). HR was higher in ISH than in NT and it was higher in women ( approximately 5 bpm) in whom it decreased with age. The prevalence of ISH is not negligible in HT (30% men, 25% women), with a high prevalence in young subjects and elevated PP, MAP and HR values. These data should be taken into account as elevated ISH, PP and HR are considered as cardio-vascular risk factors.

Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) Trial of Cardiovascular Events in High-Risk Hypertensive Patients: Rationale, Design, and Methods

Hypertension continues to be a major public health issue in the world. To combat this problem, many anti-hypertensive drugs have been developed and proven effective at controlling blood pressure in the last half century. In recent decades, antihypertensive drugs have been shown to have cardiovascular benefits beyond the reduction of blood pressure, and the focus has shifted to clarification of these effects. Angiotensin II receptor antagonists and calcium channel blockers are the most widely used antihypertensive drugs in Japan. However, these two classes of drugs have not yet been compared with respect to their efficacy for treating cardiovascular events. The Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) trial described herein is a prospective, multicenter, randomized, open-label, active-controlled, 2-arm parallel group comparison with a response-dependent dose titration and blinded assessment of endpoints in high-risk hypertensive patients treated with either an angiotensin II receptor antagonist (candesartan cilexetil) or a third-generation calcium channel blocker (amlodipine besilate). The eligibility criteria in this study were 1) age between 20 and 85 years; 2) systolic blood pressure (SBP) > or = 140 mmHg in those below 70 years of age or > or = 160 mmHg in those above 70 years of age or diastolic blood pressure (DBP) > or = 90 mmHg on two consecutive measurements at clinic; and 3) at least one of the following high risk factors for cardiovascular events: a) SBP > or = 2180 mmHg or DBP > or = 110 mmHg on two consecutive visits, b) type 2 diabetes mellitus (fasting blood glucose > or = 126 mg/dl, casual blood glucose > or = 200 mg/dl, HbA1c > or = 6.5%, 2 h blood glucose on 75 g oral glucose tolerance test (OGTT) > or = 200 mg/dl, or current treatment with hypoglycemic therapy), c) history of cerebral hemorrhage, cerebral infarction, or transient ischemic attack until 6 months prior to the screening, d) left ventricular hypertrophy on either echocardiography or ECG, angina pectoris, or history of myocardial infarction until 6 months prior to screening, e) proteinuria or serum creatinine > or = 1.3 mg/dl, and f) symptoms of arteriosclerotic artery obstruction. The therapeutic goals of blood pressure control were set as follows: SBP < 130 mmHg and DBP < 85 mmHg for patients below 60 years of age, SBP < 140 mmHg and DBP < 90 mmHg for those in their 60s, SBP < 150 mmHg and DBP < 90 mmHg for those in their 70s, and SBP < 160 mmHg and DBP < 90 mmHg for those in their 80s. A total of 3,200 patients, equally allocated to each of the two treatment arms, were required based on a two-sided alpha level 0.05 and 90% power. The CASE-J is also the first study to employ the newly developed Automatic Bar Code Data-Capturing/Allocation, Booking & Trial Coding, Data Management (ABCD) system for data collection and management. Enrollment of patients started in September 2001 and ended in December 2002. Follow-up data will be collected every 6 months until December 2005. The CASE-J trial will provide important evidence on the comparative effectiveness of candesartan cilexetil and amlodipine besilate on cardiovascular morbidity and mortality among Japanese. In addition, the use of the ABCD system is expected to contribute to the development of more efficient data management systems for large-scale clinical trials.

Benefits of antihypertensive pharmacologic therapy and blood pressure reduction in outcome trials

In a quantitative overview of published trials, we investigated whether pharmacologic properties of antihypertensive drugs, as opposed to reduction in blood pressure, explain cardiovascular outcomes in hypertensive or high-risk patients. We used meta-regression to investigate the association between the odds ratios of outcome (experimental vs. reference treatment) and the corresponding blood pressure differences between study groups. Thus, we correlated odds ratios with between-group differences in systolic pressure. We then compared odds ratios of benefit observed in recent trials with those predicted by meta-regression on the basis of the differences in systolic pressure between randomized groups. Among nine actively-controlled trials in hypertension, significant differences in systolic pressure (follow-up minus baseline) between randomized groups (experimental minus reference) were observed in the ALLHAT, CAPPP, MIDAS, and NORDIL trials. Furthermore, the differences in achieved systolic and/or diastolic pressure between study groups were also significant in the hypertension trials and studies in high-risk patients, which involved untreated control patients. The differences between the observed odds ratios and those predicted by meta-regression did not reach statistical significance except for NORDIL and the single-drug therapy subgroup of the PROGRESS trial. In NORDIL, the risk of stroke was lower on diltiazem than on the older drug classes despite a 3.1 mm Hg higher systolic pressure on the calcium channel blocker. In PROGRESS, perindopril alone reduced blood pressure by 5/3 mm Hg, but did not affect the incidence of all cardiovascular events or the recurrence of stroke. In conclusion, the finding that in the reviewed trials blood pressure reduction largely accounted for outcome emphasizes the desirability of tight blood pressure control. The hypothesis that blood pressure-lowering medications might influence cardiovascular prognosis over and beyond their antihypertensive effect remains to a large extent unproved.

Randomized, comparative, double-blind study of amlodipine vs. nicardipine as a treatment of isolated systolic hypertension in the elderly

A 90-day, multicenter, randomized, double-blind, parallel-group study was conducted to compare the efficacy of amlodipine (once a day) with nicardipine (two to three times a day), in the treatment of isolated systolic hypertension (ISH) in the elderly. Patients (n = 133) aged > or = 60 years, with ISH were randomized to receive either amlodipine 5 mg/day, or nicardipine 60 mg/day (titrated if necessary to 10 mg/day and 100 mg/day, respectively) for 90 days. Efficacy was assessed by measuring office blood pressure (BP), and 24-h ambulatory blood pressure monitoring (ABPM). The two treatments substantially and comparably reduced office systolic blood pressure (SBP) and pulse pressure (PP), and also produced a slight decrease in diastolic blood pressure (DBP). Amlodipine reduced SBP, as assessed by ABPM, to a significantly greater extent than nicardipine. Both treatments were well-tolerated. The sustained effect of amlodipine, compared with nicardipine, was reflected in its significantly greater antihypertensive activity, particularly during the nocturnal period, as assessed by ABPM. The study demonstrates that once a day dose of amlodipine is an effective antihypertensive treatment for elderly ISH patients.

Hypertension in the elderly

Both systolic and diastolic blood pressure increase with advanced age and more than 50% of hypertensive patients are aged above 65 years. Age-related vascular and neuro-humoral changes are important factors leading to the development of hypertension in the elderly and the increase in systolic and diastolic blood pressure with age in any individual is a consequence of the relative change in arterial resistance and stiffness. Therefore, hypertension is predominantly or purely systolic in the elderly both in women and men. The risks of hypertensive patients over the age of 65 years are significant and several trials have provided compelling evidence that treatment of hypertension in the elderly is beneficial in terms of reduced morbidity and mortality. Goal blood pressure should be similar in older and younger patients. Lifestyle modifications are of proven benefit and may be the only therapy needed for stage 1 hypertension. The Sixth report of the JNC recommends diuretics, specifically thiazide diuretics as the initial choice for the treatment of elderly patients without any comorbid conditions. Beta-blockers are less effective than thiazides as first line treatment and may only reduce stroke events. Recently, dihydropiridine calcium antagonists have been advocated as first choice agents for the treatment of hypertension in the elderly and are suitable alternatives when diuretics are ineffective, contraindicated or not tolerated. Newer drugs such as AT1 antagonists are also effective in lowering blood pressure in the elderly but large scale data concerning their protective effects are still lacking.

Managing the hypertensive patient with ischemic heart disease

Thiazide diuretics, b-blockers, calcium channel blockers, and angiotensin converting enzyme (ACE) inhibitors are all superior to placebo for the primary prevention of coronary events in patients with hypertension. Recent studies have shown that ACE inhibitors are better than other antihypertensive agents in lowering overall cardiovascular morbidity and mortality, especially stroke. Blood pressure should be aggressively lowered (to < 140/90 mm Hg), especially in diabetic patients (to < 130/80 mm Hg), but care should be exercised in lowering the diastolic blood pressure below 65 mm Hg in patients with significant occlusive coronary artery disease. Hypertension in patients with stable angina should be treated with a b-blocker (alternatively a calcium channel blocker) together with an ACE inhibitor. Patients with hypertension and acute coronary syndrome (unstable angina or myocardial infarction) should be treated with a b-blocker, and with an ACE inhibitor if there is left ventricular dysfunction. A thiazide diuretic and/or a dihydropyridine calcium channel blocker could be added for blood pressure control. Calcium channel blockers should be avoided if there is significant left ventricular dysfunction.

Is hypertension a leading cause of heart failure in Chinese?

1. There is considerable uncertainty regarding the importance of various risk factors in the development of heart failure. Most data are from Caucasian populations, where hypertension and coronary artery disease appear dominant. 2. Because it cannot be presumed that risk factor profiles will be identical for all races, we reviewed the literature on the aetiology of heart failure in Chinese. 3. There are, apparently, no long-term prospective studies defining the risk factors for heart failure in Chinese. Studies from Hong Kong in the 1990s point to an overlap of risk factors (especially hypertension, ischaemic heart disease and diabetes) and a high prevalence of diastolic heart failure (66%). Antihypertensive drug treatment appears likely to protect against the development of heart failure but end-points from formal trials are too small to be certain. 4. Available data, short of being definitive, point to hypertension being the most important identifiable risk factor in Chinese with heart failure. This may change with diabetes mellitus becoming more prevalent in the Chinese population.

High blood pressure in the geriatric population: treatment considerations

Increases in blood pressure (BP), particularly systolic BP, have traditionally been considered to be a normal or "physiologic" component of the aging process. However, it is now clear that elevated BP, particularly systolic BP, represents a pathophysiologic manifestation of altered cardiovascular physiology and structure, ultimately manifesting as increased cardiovascular morbidity and mortality (myocardial infarction, stroke, and total cardiovascular death rates). More than one half of the population aged 65 or older have hypertension, defined as BP > or = 140/90 mm Hg. Framingham data indicate that the risk of coronary heart disease increases with lower diastolic BP at any level of systolic BP > or = 120 mm Hg, thus further stressing the importance of pressure-induced arterial vascular compliance changes and introducing pulse pressure as an important predictor of cardiovascular risk. Geriatric hypertension is generally of a salt-sensitive nature and often associated with impaired baroreflex function. Reduction in sodium intake is important and effective in older patients, and should be initiated before or together with drug therapy. Encouraging data from clinical trials now strongly support the aggressive anti-hypertensive treatment of elderly patients. A recent meta-analysis of eight outcome trials evaluating the risks of treated and untreated isolated systolic hypertension has demonstrated a 30% reduction in combined fatal and nonfatal stroke, a 26% reduction in fatal and nonfatal cardiovascular events, and a 13% reduction in total mortality. Those drugs effective in younger patients also appear effective in the elderly; low-dose thiazides (alone or in combination with potassium sparing agents), beta blockers, long-acting dihydropyridine calcium antagonists, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers all have demonstrated efficacy. In selecting an agent, it is important to consider comorbid disease states, and to recognize the potential of all nonsteroidal anti-inflammatory drugs, whether conventional or cyclooxygenase-2 specific, to increase BP or interfere with other antihypertensive agents. In general, the elderly should be treated to target BP levels identical to those suggested for younger patients, although a more gradual reduction to target, perhaps with an intermediate BP goal of < 160 mm Hg, may be advisable.

Impact of circadian amplitude and chronotherapy: relevance to prevention and treatment of stroke

The long-acting calcium antagonist nifedipine reduces the incidence of stroke in Eastern Asia, as shown by the Shanghai Trial Of Nifedipine in the Elderly (STONE) and the Systolic Hypertension in China (Syst-China) trials. Recent trials in Japan have shown that benidipine may be more efficient than the former drug in preventing strokes in the elderly. Benidipine, commonly prescribed in Japan for a definite depressor effect, reportedly without causing remarkable fluctuations in blood pressure (BP), is investigated herein from a chronobiological viewpoint. Eighteen subjects (nine women and nine men, 39 to 87 years of age) with essential hypertension (office and ambulatory systolic, S/diastolic, D BP values above 160/95 mm Hg and 130/80 mm Hg, respectively) were enrolled in this investigation. Ambulatory BP was monitored at 30-min intervals for at least 24 h (ABPM-630, Colin Medical) before and after 4 weeks of crossover treatment with nifedipine tablets (twice daily, 20 mg/d) and benidipine (once daily, 4 mg/d, in the morning). The results indicate that: 1) benidipine and nifedipine reduce 24-h daytime (10:00-20:00) and nighttime (00:00-06:00) averages of SBP and DBP (P < 0.001); 2) the circadian double amplitude of BP is decreased after treatment with benidipine (from 28.6 to 21.1 mm Hg SBP and from 19.7 to 15.2 mm Hg DBP; P< 0.05), while the day-night difference in SBP is increased after treatment with nifedipine (18.6 vs 27.9 mm Hg, P< 0.01); and 3) the increase in the day-night difference of heart rate (HR) is significant after treatment with benidipine (13.6 vs 18.8 beats per minute, bpm; P< 0.05), but not with nifedipine. We have previously evaluated the usefulness of the circadian amplitude of BP as a prognostic tool of cardiovascular outcome, and found that an excessive circadian SBP or DBP amplitude was associated with an increased risk of vascular disease. The fact that benidipine reduces the circadian BP amplitude may be one reason for the superiority of this treatment over nifedipine in preventing an adverse outcome. A reduced heart rate variability (HRV) also predicts adverse cardiovascular outcomes in patients with overt cardiovascular disease and in hypertensive subjects. The fact that benidipine increases the day-night difference in HR may be another reason for the positive effects of this treatment.

Calcium channel blockade in combination with angiotensin-converting enzyme inhibition or angiotensin II (AT(1)-receptor) antagonism in hypertensive diabetics and patients with renal disease and hypertension

Effective reduction in blood pressure (BP) improves survival and morbidity in hypertensive patients. Combination therapy with multiple antihypertensive agents is frequently required in clinical practice and therapeutic trials to achieve target BP. Patients at elevated cardiovascular risk achieve the greatest benefit from equivalent reduction in BP and also require more stringent BP control. In patients with hypertension and diabetes mellitus or renal disease, BP control is of primary importance and blockade of the renin-angiotensin system (RAS) should be the initial therapeutic intervention. Choice of combination therapy has been insufficiently studied in major clinical cardiovascular endpoint trials. Diuretic therapy remains the logical addition to RAS blockade. Despite previous debate, the available evidence suggests long-acting calcium-channel blockers are also a safe and very effective addition to improve BP control further. The choice of antihypertensive combination therapy should not override the fundamental necessity of lowering BP to target levels.

A retrospective electronic chart review of blood pressure changes in elderly patients treated with amlodipine or an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker

BACKGROUND

Despite the high costs of managing hypertension, pharmacologic intervention is cost-effective, particularly in patients at highest risk for cardiovascular events. The prevalence of hypertension in the elderly and the age-associated risks of coronary artery disease and stroke suggest that early identification and aggressive treatment should be priorities in this population.

OBJECTIVE

The aim of this study was to compare the effect of amlodipine and angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) in the treatment of essential hypertension in elderly patients (>60 years) in an actual practice setting.

METHODS

This was a retrospective cohort analysis using electronic medical records stored in the Physicians Data Corporation cardiology database. Patients aged >60 years who received care from a cardiologist and who had a recorded diagnosis of hypertension during 1997 or 1998 were identified. For inclusion, patients had to have received an initial prescription for amlodipine, an ACE inhibitor, or an ARB at the index visit. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) readings from the index visit and > or =1 subsequent visit (<180 days after the index visit) were assessed.

RESULTS

A total of 192 patients (56.3% male; mean age, 71.9 years) met the inclusion criteria. Amlodipine-treated patients experienced a mean decrease in SBP of 26.7 mm Hg, compared with 18.8 mm Hg in patients receiving an ARB and 15.8 mm Hg for patients receiving an ACE inhibitor (P = 0.008, amlodipine vs ACE inhibitor). DBP decreased 8.8 mm Hg with amlodipine, 8.7 mm Hg with an ARB, and 6.2 mm Hg with an ACE inhibitor. After adjusting for age, sex, and disease severity, amlodipine-treated patients were -4 times as likely to move to a better blood pressure stage than patients treated with an ARB or an ACE inhibitor (odds ratio, ARB vs amlodipine: 0.245; 95% CI, 0.080-0.753; odds ratio, ACE inhibitor vs amlodipine: 0.234; 95% CI, 0.072-0.761).

CONCLUSION

Results of this study indicate that in patients aged >60 years, amlodipine may be an effective therapy for hypertension.

Carcinogenicity of antihypertensive therapy

Several studies have suggested that antihypertensive treatment may promote cancer through unknown mechanisms. Early retrospective studies implicated reserpine in breast cancer, but data from prospective studies and meta-analysis of several case-controlled studies showed only a weak association between reserpine and breast cancer which, although statistically significant, is of little clinical concern. Data from case-controlled studies and several cohort studies suggested an association between the use of a diuretic and the occurrence of renal cell cancer, particularly in women. A recent study showed an association between the use of a diuretic and the occurrence of colon cancer. Several prospective studies showed that treatment with atenolol may increase mortality from malignancy. However, other studies that analyzed data from several thousand patients could not confirm this association. In three prospective and a few case-controlled studies, angiotensin converting enzyme inhibitors were not associated with increased mortality from malignancy. In addition, a recent retrospective study showed that long-term use of angiotensin converting enzyme inhibitors had a protective effect against malignancy. Data from three large case-controlled studies and the combined data from eight randomized controlled studies and seven longitudinal studies showed a similar risk for malignancy among users and nonusers of calcium antagonists. Until further data from prospective clinical trials are available, we advise caution about long-term diuretic therapy in women. With regard to other antihypertensive drug classes, we suggest continuing the management of hypertension according to current treatment guidelines with little fear of any substantial cancer risk.

Calcium modulation of adherens and tight junction function: a potential mechanism for blood-brain barrier disruption after stroke

BACKGROUND

This review deals with the role of calcium in endothelial cell junctions of the blood-brain barrier (BBB). Calcium is critical for adherens junction function, but it appears that calcium is also important in regulating tight junction function necessary for the barrier characteristics of cerebral microvessels.

SUMMARY OF REVIEW

The BBB is critical for brain homeostasis and is located at the cerebral microvessel endothelial cells. These endothelial cells maintain their barrier characteristics via cell-cell contacts made up of adherens and tight junctions. Adherens junctions are calcium dependent; recent evidence suggests that calcium also affects tight junctions. After stroke, there is a disruption of the BBB. Interfering with calcium flux under hypoxic conditions can prevent BBB breakdown. Calcium may alter BBB junction integrity by a number of different signal transduction cascades, as well as via direct interaction of calcium ions with junction proteins. It remains to be determined whether clinical use of calcium channel antagonists is a viable means to reduce BBB disruption after stroke.

CONCLUSIONS

With the widespread use of calcium channel blockers as clinical treatments for hypertension, which is a risk factor for stroke, the exact role of calcium in modulating BBB integrity needs to be elucidated.

Large therapeutic studies in elderly patients with hypertension

Hypertension, including isolated systolic hypertension, is one of the major risk factors for stroke and coronary heart disease in elderly subjects, and is a common antecedent of heart failure, because it increases the risk either directly through increased after-load or indirectly as a risk factor for acute myocardial infarction. The proportion of people aged 65 and above is increasing. It is well documented that hypertension treatment in elderly patients reduces cardiovascular morbidity and mortality more than could be expected from the results of trials in middle-aged subjects. Most of the trials on old and new antihypertensive drugs have yielded similar results. Nevertheless, evidence in subjects above 80 years of age is still limited. Hypertension (systolic-diastolic) and isolated systolic hypertension should be treated in elderly patients, starting with low doses of medication, particularly diuretics alone or in combination with beta-blockers or angiotensin-converting enzyme inhibitors. Isolated systolic hypertension could also be treated with a long-acting calcium antagonist starting with low doses. The large therapeutic studies, because of the limitations imposed upon conclusions by the selection and exclusion criteria, by the statistical techniques that established the trial designs and by other study-related constraints, cannot be applied to all elderly patients seen in daily practice. Specifically patients may differ in age, severity of illness, presence of morbidity and a myriad of other clinical nuances. Non-pharmacological measures such as lifestyle modifications (losing weight, limiting alcohol intake, reducing sodium intake and exercise), should be instituted or improved if they existed, to maximise the benefit and minimise the risk inherent in pharmacological treatment. A medical approach may reconcile the results of these large therapeutic studies with 'real life' quality of life and patients' preferences in order to improve treatment compliance.

Evidence-based evaluation of calcium channel blockers for hypertension: equality of mortality and cardiovascular risk relative to conventional therapy

OBJECTIVES; We present a meta-analysis based on three recent, substantial, randomized outcome trials and several smaller trials that compared calcium channel blockers (CCBs) with conventional therapy (diuretics or beta-blockers) or with angiotensin-converting enzyme (ACE) inhibitors.

BACKGROUND

There is continuing uncertainty about the safety and efficacy of CCBs in the treatment of hypertension. Previous meta-analyses conflict and suggest that CCBs increase myocardial infarction (MI) or protect from stroke.

METHODS

Standard procedures for meta-analysis were used to analyze three major trials on 21,611 patients and another three lesser studies to a total of 24,322 patients.

RESULTS

Calcium channel blockers have a strikingly similar risk of total and cardiovascular mortality and of major cardiovascular events to conventional therapy. Calcium channel blockers give a lower risk of nonfatal stroke (-25%, p = 0.001) and a higher risk of total MI (18%, p = 0.013), chiefly nonfatal (18%). After performing the Bonferroni correction for multiplicity, these p values become 0.004 and 0.052, respectively. When compared with ACE inhibitors in 1,318 diabetic patients, CCBs had a substantially higher risk of nonfatal (relative risk [RR] = 2.259) and total MI (RR = 2.204, confidence interval 1.501 to 3.238; p = 0.001 or 0.004 with Bonferroni correction). Total and cardiovascular mortality rates are similar. To confirm the hypothesis that ACE inhibitors are superior to CCBs in diabetic patients requires more trial data, especially with renal end points.

CONCLUSIONS

Mortality (total and cardiovascular) and major cardiovascular events with CCBs were apparently similar to those events seen with conventional first-line therapy (diuretics or beta-blockers). Stroke reduction more than balanced increased MI. In diabetics, CCBs may be less safe than ACE inhibitors.

Factors influencing the systolic blood pressure response to drug therapy

In the early stage of hypertension, diastolic blood pressure has greater prognostic importance, but in the elderly, systolic blood pressure is the most important marker of cardiovascular complications. Therefore, the need for more strict control of this component of blood pressure must be reconsidered. The benefit obtained in different studies in the elderly suggests that the treatment of isolated systolic hypertension is associated with a reduction in overall cardiovascular mortality of 22%, in coronary heart disease mortality of 26%, and in stroke mortality of 33%. However, a higher percentage of patients (73%) attain the diastolic goal of <90 mm Hg, while only 34% have systolic pressure reduced to <140 mm Hg. In a review of randomized trials comparing at least four different antihypertensive drugs, significant differences in systolic blood pressure reduction have not been demonstrated, except in black populations, in whom calcium channel blockers and diuretics seem to be more effective. In patients with isolated systolic hypertension, data are inconclusive, but calcium channel blockers and diuretics appear to lower blood pressure to a greater degree than do other antihypertensive drugs. Two main predictors of difficulty in controlling systolic blood pressure are the baseline blood pressure and the presence of diabetes. Other predictors are the duration of arterial hypertension, older age, the presence of target organ damage and associated clinical conditions (myocardial infarction, stroke, chronic renal failure), and an elevated serum uric acid level. It appears that the profile of patients with a poorer therapeutic response includes a greater severity of hypertension and/or the presence of cardiovascular disease.

Results of antihypertensive treatment trials in the elderly

The prevalence of arterial hypertension is age-dependent, and with the prolongation of life expectancy the number of elderly subjects with arterial hypertension is very relevant. Epidemiologic studies have shown that arterial hypertension is a risk factor in elderly patients and therefore the physician must know if the pharmacologic and nonpharmacologic reduction of blood pressure values is associated with a corresponding decrease in systolic-diastolic or isolated systolic hypertension. Clinical trials have shown that the lowering of blood pressure values is commonly associated with a decrease in cardiovascular events. So far, the reduction of blood pressure per se appears more relevant to the cardiovascular benefit than does a particular class of antihypertensive agents. The benefit of antihypertensive treatment has been shown up to the age of 80 years, while there are no clear indications of a benefit in persons older than 80 years. While sufficient data suggest that a diastolic blood pressure between 80 and 90 mm Hg is associated with a clear benefit in elderly patients, the data in support of a systolic reduction below 140 mm Hg require further direct confirmation.

Pulsatile blood pressure component as predictor of mortality in hypertension: a meta-analysis of clinical trial control groups

OBJECTIVE

Although current guidelines rest exclusively on the measurement of systolic and diastolic blood pressures, the arterial pressure wave is more precisely described as consisting of a pulsatile (pulse pressure) and a steady (mean pressure) component. This study explored the independent roles of pulse pressure and mean pressure as predictors of mortality in a wide range of patients with hypertension.

DESIGN AND METHODS

This meta-analysis, based on individual patient data, has combined results from the control groups of seven randomized clinical trials conducted in patients with systolo-diastolic or isolated systolic hypertension. The relative hazard rates associated with pulse pressure and mean pressure were calculated using Cox's proportional hazard regression models with stratification for the seven trials and with adjustment for sex, age, smoking and the other pressure.

RESULTS

A 10 mmHg wider pulse pressure at baseline, which corresponds to approximately one-half of its standard deviation, was independently associated with an increase in risk by 6% for total mortality (P = 0.001), 7% for cardiovascular mortality (P = 0.01), and 7% for fatal coronary accidents (P = 0.03). The corresponding increase in risk of fatal stroke was similar (+6%, P = 0.27) but there were too few strokes to reach statistical significance. In similar analyses, mean pressure was not identified as an independent predictor of these outcomes. Significant interactions of pulse pressure or mean pressure with age suggested that the prognostic power of pulse pressure for fatal stroke was more important at higher age (P = 0.04), whereas the prognostic power of mean pressure for coronary mortality was greatest in the young (P = 0.01).

CONCLUSIONS

In hypertensive patients pulse pressure, not mean pressure, is associated with an increased risk of fatal events. This appears to be true in a broad range of patients with hypertension.

Amlodipine versus chlorthalidone versus placebo in the treatment of stage I isolated systolic hypertension

The study was to compare the effects of amlodipine (calcium channel antagonist), chlorthalidone (diuretic), and placebo in adults more than 50 years of age with stage 1 isolated systolic hypertension (ISH). After a 4-week placebo run-in phase, 150 patients were randomly assigned in a double-blind fashion to treatment with 5 mg of amlodipine (n = 48), 15 mg of chlorthalidone (n = 50), or placebo (n = 52). Patients who failed to meet the systolic blood pressure (BP) reduction goal by week 4 had their dose increased to 10 mg of amlodipine or 30 mg of chlorthalidone, and maintained at this increased dose for 12 weeks. Results showed a mean reduction (mean +/- SD) in sitting systolic BP from baseline to the last treatment visit of -14.6+/-12.2 mm Hg (95% confidence interval [CI] -18.2, -11.0), -14.0+/-13.46 mm Hg (95% CI -17.8, -10.2), and -3.4+/-11.83 mm Hg (95% CI -6.7, -0.1) for the amlodipine, chlorthalidone, and the placebo treatment groups, respectively. Both active treatments showed significantly greater reductions than the placebo group (P < or = .001), but were not significantly different from each other. Sixty-seven percent of the amlodipine, 69% of the chlorthalidone, and 25% of the placebo-treated patients reached the protocol defined systolic BP goal (P = .001). Both active treatment groups showed a trend of better systolic BP response in older patients (> or =65 years). Secondary efficacy measures including pulse pressure, standing systolic, diastolic, and the 24-h ambulatory BP were also statistically significantly improved for both active treatments at the end of treatment, except for chlorthalidone in standing diastolic BP. Adverse events that occurred during the study were as expected and were well tolerated. The results of this study support the efficacy and safety of amlodipine and chlorthalidone for the treatment of stage 1 ISH during 20 weeks of treatment.

Treatment of hypertension in the elderly

Hypertension is a common condition among older people in most developed countries, and is a very important, if not the most important, risk factor for all subtypes of vascular disease and death. Many clinical trials in older people have demonstrated significant reductions in myocardial infarctions and strokes when antihypertensive drugs are provided. Lifestyle modifications are still recommended because they can lower a surrogate end point--blood pressure--but there are no data showing they reduce event rates. It is not appropriate to limit the choice of initial drug for hypertensive older individuals to a single class of agents, since so many older people have other medical problems that affect this decision. Monotherapy with an alpha blocker, however, is no longer recommended, even for men with hypertension and benign prostatic hypertrophy, as doxazosin was associated with a higher rate of cardiovascular events in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial. The classic strategy of an initial diuretic (for at least 1 month) will likely be verified by the final results of ongoing randomized trials, expected in 2003. Until then, this strategy is effective, inexpensive, and unlikely to cause many adverse effects. Probably the most important exhortation, however, should be to achieve the blood pressure goal appropriate for the patient's risk status. Numerous clinical trials in older hypertensive patients have shown that more benefits accrue when the goal blood pressure is achieved than if a specific antihypertensive agent is chosen as initial therapy. Future cardiovascular risk may be related directly to the blood pressure attained, rather than to how it was attained.

Questionnaire survey on the Japanese guidelines for treatment of hypertension in the elderly: 1999 revised version

A questionnaire survey was administered to Japanese clinical specialists in hypertension in order to gauge their opinions on the 1999 revised version of the Guidelines for Hypertension in the Elderly prepared by the Comprehensive Research Project on Aging and Health of the Ministry of Health and Welfare. Out of 162 council members of the Japanese Society of Hypertension, 122 (75%) replied. The majority (93%) of respondents approved of the guidelines in general, and 72% of them approved of the age-related setting of a therapeutic goal for blood pressure. Sixty-five percent of respondents selected long-acting Ca antagonists, ACE inhibitors and low-dose diuretics as first-line agents for hypertension without complications in the elderly. The results of the questionnaire survey should be reflected in the next version of the guidelines.

Epidemiology of hypertension in the elderly

In Western populations, mean systolic and diastolic blood pressures rise with advancing age up to the sixth decade of life, whereupon systolic blood pressure continues to increase and diastolic pressure starts to decline. The ensuing widening of pulse pressure is mainly ascribed to stiffening of the arterial vasculature. When hypertension is defined as systolic blood pressure of at least 140 mm Hg and/or diastolic pressure of at least 90 mm Hg, its prevalence amounts to 60%-70% of the population above 60 years of age. About 60% of these hypertensives have isolated systolic hypertension--that is, elevated systolic pressure and normal diastolic pressure. It should be realized, however, that approximately 25% of those labeled hypertensive on the basis of conventional blood pressure measurements have normal blood pressure on ambulatory blood pressure monitoring, or so-called white-coat, isolated clinic, or nonsustained hypertension. There is little doubt that elevated blood pressure leads to a number of cardiovascular complications. Whereas diastolic blood pressure has been emphasized for many years, the paradigm has shifted toward systolic blood pressure. In addition, pulse pressure has been shown to be an important predictor of cardiovascular events and death, above and beyond the predictive power of mean blood pressure.

Drugs in pregnancy. Antihypertensives

Fifty per cent of pregnancies are unplanned, and 1-6% of young women have pre-existing hypertension. However, no commonly used antihypertensive agent is known to be teratogenic. ACE inhibitors (and angiotensin-receptor antagonists) should be discontinued due to fetotoxicity. Five to 10% of pregnant women have hypertension, of which pre-existing hypertension is but one type. There is consensus that severe maternal hypertension (blood pressure >or=170/110 mmHg) should be treated to minimize the risk of acute cerebrovascular complications. Parenteral hydralazine may be associated with a higher risk of maternal hypotension, and intravenous labetalol with neonatal bradycardia. There is no consensus that mild-to-moderate hypertension in pregnancy should be treated. Clinical trials indicate that transient severe hypertension, antenatal hospitalization, proteinuria at delivery and neonatal respiratory distress syndrome may be decreased by normalizing blood pressure, but intrauterine fetal growth restriction may be increased. Methodological problems with published trials warrant cautious interpretation of these findings. Methyldopa and beta-blockers have been used most extensively, although atenolol may impair fetal growth in particular and should be avoided.

Improved outcomes with antihypertensive medication in the elderly with isolated systolic hypertension

Isolated systolic hypertension affects over 15% of all individuals aged >60 years. In the elderly, systolic hypertension is a major modifiable cardiovascular risk factor. Systolic blood pressure (SBP) is associated with higher risk of an adverse outcome, whereas diastolic blood pressure (DBP) is inversely correlated with total mortality, independent of SBP, highlighting the role of pulse pressure as a risk factor. Three placebo-controlled outcome trials on antihypertensive drug treatment in older patients with isolated systolic hypertension have been published: the Systolic Hypertension in the Elderly Program (SHEP), the Systolic Hypertension in Europe (Syst-Eur) Trial and the Systolic Hypertension in China (Syst-China) Trial. These 3 trials demonstrated the benefit of antihypertensive drug treatment. A meta-analysis was performed by pooling the patients from these 3 trials with a subset of patients with isolated systolic hypertension from 5 other trials in the elderly. The pooled results of 15,693 older patients with isolated systolic hypertension prove that antihypertensive drug treatment isjustified if on repeated clinic measurements SBP is 160 mm Hg or higher.

Calcium channel blockers in treatment of hypertension

Calcium channel blockers (CCBs) are among the most often prescribed drugs for the treatment of hypertension, but there is still uncertainty regarding the risks and benefits of their use as first-line drugs in the treatment of hypertension. Compared with placebo, dihydropyridine CCBs (long-acting nifedipine and nitrendipine) reduce the risk for cardiovascular endpoints, and in a pooled analysis of available studies on treatment of hypertension, significantly decrease the risk for strokes and cardiovascular and total mortality. This also holds true for patients with diabetes who have a clearly reduced risk when treated with CCBs as compared with placebo. However, compared with other active treatments in mixed study populations, CCBs are associated with a small risk increase for myocardial infarction and heart failure, but for cardiovascular mortality, there is only a very small and nonsignificant trend to a risk increase, and total mortality is similar. Among patients with diabetes, compared with angiotensin-converting enzyme inhibitors in particular, available data suggest that CCB use is associated with a moderate increase in cardiac endpoints. Therefore, among patients with diabetes and those with heart failure, angiotensin-converting enzyme inhibitors are preferable as first-line drugs; among the large fraction of patients without these conditions, there is no convincing evidence that long-acting dihydropyridine or nondihydropyridine CCBs are inferior to other blood pressure-lowering drugs. In these patients, the choice of blood pressure-lowering medication can be based on the expected tolerability, costs, and personal preferences.

Risk and benefit of treatment of isolated systolic hypertension in the elderly: evidence from the Systolic Hypertension in Europe Trial

The Syst-Eur trial investigated whether active treatment starting with the dihydropyridine calcium channel blocker (CCB) nitrendipine, could reduce the cardiovascular complications of isolated systolic hypertension (ISH) in the elderly. The intention-to-treat analysis showed that active treatment improved outcome. The per-protocol analysis largely confirmed these results. The effect of treatment on total and cardiovascular mortality might be attenuated in very old patients. Further analysis also suggested benefit in those patients who remained on nitrendipine monotherapy. Active treatment was more beneficial in patients with diabetes as compared with those without diabetes at entry and reduced the incidence of dementia by 50%. Analyses of data from the Ambulatory Blood Pressure Monitoring (ABPM) Side Project suggested that most of the benefit of treatment was seen in patients with a daytime systolic BP > or = 160 mm Hg. Finally, a meta-analysis partly based on Syst-Eur data showed that in older hypertensive patients pulse pressure and not mean pressure is the major determinant of cardiovascular risk.