Effects of different regimens to lower blood pressure on major cardiovascular events in older and younger adults: meta-analysis of randomised trials

Treating high blood pressure: is reaching the target more important than the means? Yes, the target is more important

The effectiveness of hypertension treatments is attributed either to the change in blood pressure, independent of the means used, or to an important contribution of appropriate drug selection: this debate probably stems from an inappropriate comparison. Treating essential hypertension in relatively healthy patients without advanced vascular disease and co-morbidities affords cardio-vascular protection by the lowering of the mechanical shear stress determined by blood pressure per se: thus, lowering blood pressure is the critical step, while the methods used can only differ through side effects. This treatment is, in fact, a lifetime prophylaxis, as hypertension, rather than a disease, is a symptom affecting one tail of the Gaussian distribution of blood pressure across the normal population. Treating hypertension in the context of diseases, like diabetes mellitus, congestive heart failure, left ventricular hypertrophy, and advanced atherosclerosis, would be improper if focused on just one symptom, while the appropriate treatment must include options which exhibit a more extended profile to include effectiveness on cardiac hypertrophy, insulin resistance, cardiac output, and systemic hemodynamics: thus, drugs may be different in their effectiveness and in the cardio-vascular protection afforded, even though the trials quoted in favour of this thesis were designed to compare drugs in their ability to lower blood pressure rather than in improving the overall complex clinical derangements. In conclusion, while the answer to the question is a sharp YES when dealing with primary prevention, it might be a NO, still clouded by contradictory and inconclusive evidence when dealing with secondary prevention and/or treatment of complex disease conditions and co-morbidities.

Antihypertensive efficacy and safety of olmesartan and ramipril in elderly patients with mild to moderate systolic and diastolic essential hypertension

OBJECTIVE

To compare the efficacy and safety of olmesartan medoxomil (O) and ramipril (R) in elderly patients with essential arterial hypertension.

METHODS

After a 2-week placebo washout, 351 elderly hypertensive patients aged 65-89 years (office sitting diastolic blood pressure, DBP, 90-109 mmHg and office sitting systolic blood pressure, SBP, 140-179 mmHg) were randomized double-blind to 12-week treatment with O 10 mg or R 2.5 mg once daily. After the first 2 and 6 weeks, doses could be doubled in non-normalized (blood pressure <140/90 mmHg for non-diabetic and <130/80 mmHg for diabetic) subjects, up to 40 mg for O and 10 mg for R. Office blood pressures were assessed at randomization, after 2, 6 and 12 weeks of treatment; 24-h ambulatory blood pressure (ABP) was recorded at randomization and after 12 weeks.

RESULTS

At week 12, in the intention-to-treat population (170 patients O and 175 R) the rate of normalized subjects was significantly larger in the O group (38.8% vs 26.3% R; p = 0.013). Baseline-adjusted mean sitting office blood pressure reduction at final visit was not significantly greater under O [SBP: 16.6 (95% confidence interval 14.0/19.2) mmHg vs 13.0 (10.4/15.6) mmHg R, p = 0.206; DBP: 11.8 (10.3/13.3) mmHg vs 10.5 (9.0/12.0) mmHg, p = 0.351]. In the subgroup of patients with valid ABP recordings (38 O and 47 R), the reduction in 24-h average blood pressure was significantly (p < 0.01) larger with O [SBP: 8.9 (9.8/8.1) and DBP: 5.7 (6.3/5.1) mmHg] than with R [6.7 (7.9/5.6) and 4.4 (5.1/3.7) mmHg]. The superiority of O was particularly evident in the last 4 h from the dosing interval. The proportion of patients with drug-related adverse events was comparable in the two groups (4.0% O vs 4.5% R), as well as the number of patients discontinuing study drug because of a side-effect (8 O vs 7 R).

CONCLUSIONS

In elderly patients with essential arterial hypertension, O provides an effective, prolonged and well tolerated blood pressure control, with significantly better blood pressure normalization than R and represents a useful option among first-line drug treatments of hypertension in this age group.

Optimal management of hypertension in elderly patients

Hypertension is a common and important modifiable risk factor for cardiovascular and kidney diseases. The prevalence of hypertension, particularly isolated systolic hypertension, increases with advancing age, and this is partly due to the age-related changes in the arterial tree, leading to an increase in arterial stiffness. Therapeutic lifestyle changes, such as reduced dietary sodium intake, weight loss, regular aerobic activity, and moderation of alcohol consumption, have been shown to benefit elderly patients with hypertension. Lowering blood pressure (BP) using pharmacological agents reduces the risk for cardiovascular morbidity and mortality, with no difference in risk reduction in elderly patients compared to younger hypertensives. Guidelines recommend a BP goal of <140/90 in hypertensive patients regardless of age and <130/80 in patients with concomitant diabetes or kidney disease, and lowering the BP further has not been shown to confer any additional benefit. Moreover, the choice of antihypertensive does not seem to be as important as the degree of BP lowering. Special considerations in the treatment of elderly hypertensive patients include cognitive impairment, dementia, orthostatic hypotension, and polypharmacy.

Chronotherapy with valsartan/amlodipine fixed combination: improved blood pressure control of essential hypertension with bedtime dosing

Administration of valsartan at bedtime as opposed to upon wakening improves the sleep-time relative blood pressure (BP) decline towards a more normal dipper pattern without loss of 24-h efficacy. Amlodipine, however, has been shown to be effective in reducing BP throughout the day and night, independent of dosing time. A large proportion of hypertensive subjects cannot be properly controlled with a single medication. However, no study has yet investigated the potential differing effects of combination therapy depending of the time-of-day of administration. Accordingly, the authors investigated the administration-time-dependent BP-lowering efficacy of valsartan/amlodipine combination. The authors studied 203 hypertensive subjects (92 men/111 women), 56.7 +/- 12.5 yrs of age, randomized to receive valsartan (160 mg/day) and amlodipine (5 mg/day) in one of the following four therapeutic schemes: both medications on awakening, both at bedtime, either one administered on awakening and the other at bedtime. BP was measured by ambulatory monitoring for 48 consecutive hours before and after 12 wks of treatment. Physical activity was simultaneously monitored every min by wrist actigraphy to accurately determine the beginning and end of daytime activity and nocturnal sleep. BP-lowering efficacy (quantified in terms of reduction of the 48-h mean of systolic/diastolic BP) was highest when both hypertension medications were ingested at bedtime, as compared to any one of the three other tested therapeutic schemes (17.4/13.4 mm Hg reduction with both medications on awakening; 15.1/9.6 mm Hg with valsartan on awakening and amlodipine at bedtime; 18.2/12.3 mm Hg with valsartan at bedtime and amlodipine on awakening; 24.7/13.5 mm Hg with both medications at bedtime; p < .018 between groups). The sleep-time relative BP decline was significantly increased towards a more normal dipper pattern only when both medications were jointly ingested at bedtime (p < .001). Bedtime dosing of the combination of the two medications also resulted in the largest percentage of controlled subjects among all the assessed therapeutic schemes (p = .003 between groups). In subjects requiring combination therapy to achieve proper BP control, the association of amlodipine and valsartan efficiently reduces BP for the entire 24 h independent of dosing time. However, the greater proportion of controlled patients, improved efficacy on lowering asleep BP mean, and increased sleep-time relative BP decline suggest valsartan/amlodipine combination therapy should be preferably administered at bedtime.

Finding a niche with personalized generics: opportunities from systems-based therapeutic delivery in hypertension

A key principle in earlier eras of drug development was to deliver medicines with clinical benefits for populations. Individual patients frequently did not benefit, or experienced adverse drug reactions, and were at risk of exposure to a prolonged series of treatment trials before effective therapies were found, if available. A personalized medicines approach offers opportunities to select drugs likely to be effective or safer, based on knowledge, for example, of differences in disease-modulating receptors, in drug metabolism, or in drug transporters into cells and across tissue boundaries. This new genetic and phenotypic knowledge allows generics to be revisited and may also help to improve medicine adherence, by reducing predictable adverse effects from unwanted accumulation of a medicine or its metabolites. This review will consider effective population delivery of therapeutics to treat hypertension in order to illustrate the potential and current place of personalizing medicines to improve effective and safe use of therapeutics.

Blood pressure control in the elderly: can you have too much of a good thing?

Hypertension (especially systolic hypertension) is very common in older persons. Systolic hypertension occurs because large conduit arteries become stiffer with age. Strong evidence from randomized trials suggests that treating systolic blood pressures initially higher than 160 mm Hg is extremely beneficial, and a recent trial extended this conclusion to healthy persons over 80 years of age. However, the only trial that has directly tested the use of more aggressive treatment goals (< 140 mm Hg) in the elderly did not show benefit in those older than 75. Risks of overtreating hypertension for the elderly include falls and orthostatic hypotension, and the most compromised older persons may be the most likely to experience adverse effects. Our current state of knowledge requires clinical judgment that balances the immediacy of adverse effects versus the potential but unproven benefits of treatment in deciding whether to treat the elderly more aggressively than the goals used in randomized trials.

Effect of sibutramine on cardiovascular outcomes in overweight and obese subjects

BACKGROUND

The long-term effects of sibutramine treatment on the rates of cardiovascular events and cardiovascular death among subjects at high cardiovascular risk have not been established.

METHODS

We enrolled in our study 10,744 overweight or obese subjects, 55 years of age or older, with preexisting cardiovascular disease, type 2 diabetes mellitus, or both to assess the cardiovascular consequences of weight management with and without sibutramine in subjects at high risk for cardiovascular events. All the subjects received sibutramine in addition to participating in a weight-management program during a 6-week, single-blind, lead-in period, after which 9804 subjects underwent random assignment in a double-blind fashion to sibutramine (4906 subjects) or placebo (4898 subjects). The primary end point was the time from randomization to the first occurrence of a primary outcome event (nonfatal myocardial infarction, nonfatal stroke, resuscitation after cardiac arrest, or cardiovascular death).

RESULTS

The mean duration of treatment was 3.4 years. The mean weight loss during the lead-in period was 2.6 kg; after randomization, the subjects in the sibutramine group achieved and maintained further weight reduction (mean, 1.7 kg). The mean blood pressure decreased in both groups, with greater reductions in the placebo group than in the sibutramine group (mean difference, 1.2/1.4 mm Hg). The risk of a primary outcome event was 11.4% in the sibutramine group as compared with 10.0% in the placebo group (hazard ratio, 1.16; 95% confidence interval [CI], 1.03 to 1.31; P=0.02). The rates of nonfatal myocardial infarction and nonfatal stroke were 4.1% and 2.6% in the sibutramine group and 3.2% and 1.9% in the placebo group, respectively (hazard ratio for nonfatal myocardial infarction, 1.28; 95% CI, 1.04 to 1.57; P=0.02; hazard ratio for nonfatal stroke, 1.36; 95% CI, 1.04 to 1.77; P=0.03). The rates of cardiovascular death and death from any cause were not increased.

CONCLUSIONS

Subjects with preexisting cardiovascular conditions who were receiving long-term sibutramine treatment had an increased risk of nonfatal myocardial infarction and nonfatal stroke but not of cardiovascular death or death from any cause. (Funded by Abbott; ClinicalTrials.gov number, NCT00234832.)

Is newer always better? Re-evaluating the benefits of newer pharmaceuticals

Whether newer pharmaceuticals justify their higher costs by reducing other health expenditures has generated significant debate. We replicate a frequently cited paper by Lichtenberg on drug "offsets" and find the results disappear using a more appropriate model or updated dataset. Further, we test the suitability of similar methods using newer hypertension drugs. We find our observational results run counter to well-established clinical evidence on comparative efficacy and conclude that our model, as well as other studies that do not adequately control for unobserved characteristics that jointly determine drug choice and health expenditures, are likely subject to significant bias.

Blood pressure and outcomes in very old hypertensive coronary artery disease patients: an INVEST substudy

BACKGROUND

Our understanding of the growing population of very old patients (aged >or=80 years) with coronary artery disease and hypertension is limited, particularly the relationship between blood pressure and adverse outcomes.

METHODS

This was a secondary analysis of the INternational VErapamil SR-Trandolapril STudy (INVEST), which involved 22,576 clinically stable hypertensive coronary artery disease patients aged >or=50 years. The patients were grouped by age in 10-year increments (aged >or=80, n=2180; 70-<80, n=6126; 60-<70, n=7602; <60, n=6668). Patients were randomized to either verapamil SR- or atenolol-based treatment strategies, and primary outcome was first occurrence of all-cause death, nonfatal myocardial infarction, or nonfatal stroke.

RESULTS

At baseline, increasing age was associated with higher systolic blood pressure, lower diastolic blood pressure, and wider pulse pressure (P <.001). Treatment decreased systolic, diastolic, and pulse pressure for each age group. However, the very old retained the widest pulse pressure and the highest proportion (23.6%) with primary outcome. The adjusted hazard ratio for primary outcomes showed a J-shaped relationship among each age group with on-treatment systolic and diastolic pressures. The systolic pressure at the hazard ratio nadir increased with increasing age, highest for the very old (140 mm Hg). However, diastolic pressure at the hazard ratio nadir was only somewhat lower for the very old (70 mm Hg). Results were independent of treatment strategy.

CONCLUSION

Optimal management of hypertension in very old coronary artery disease patients may involve targeting specific systolic and diastolic blood pressures that are higher and somewhat lower, respectively, compared with other age groups.

Antihypertensive therapy among newly treated patients: An analysis of adherence and cost of treatment over years

OBJECTIVE

To perform a time-trend analysis of adherence and cost of antihypertensive treatment over four years.

METHODS

A population-based retrospective cohort study was conducted. We included subjects ≥18 years, and newly treated for hypertension with diuretics, beta-blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, or angiotensin receptor blockers between 01 January 2004 and 31 December 2007. One-year adherence to antihypertensive therapy was calculated and classified as low, low-intermediate, intermediate, high-intermediate, and high. The direct cost of antihypertensive medications was evaluated.

RESULTS

We included data for a total of 105,512 patients. The number of newly treated subjects decreased from 27,334 in 2004 to 23,812 in 2007, as well as antihypertensive drug therapy cost which decreased from €2,654,166 in 2004 to €2,343,221 in 2007. On the other hand, in the same time frame, the percentage of adherent newly treated subjects increased from 22.9% to 28.0%. Compared with subjects initiated on angiotensin receptor blockers (odds ratio [OR] = 1), the risk of nonadherence was higher in those initiated on angiotensin-converting enzyme inhibitors (OR = 1.19), combination therapy (OR = 1.44), beta-blockers (OR = 1.56), calcium channel blockers (OR = 1.67), and diuretics (OR = 4.28).

CONCLUSIONS

The findings of the present study indicate that suboptimal adherence to antihypertensive medication occurs in a substantial proportion of treated patients, and improvements in treatment adherence were obtained but are still unsatisfactory.

Stroke in women

AIMS

The aim of this article is to provide an overview of stroke in women and describe modifiable and non-modifiable risk factors for stroke.

DATA SYNTHESIS

Data supporting this article come from the National Center for Health Statistics, from American Heart Association publications, and from some of the large, multicenter trials and observational studies that inform guidelines for prevention of stroke. These data indicate that stroke is the third leading cause of death in women, that risk for stroke rises rapidly with age, and that the strongest risk factors for stroke are high blood pressure and atrial fibrillation, as well as diabetes and smoking. Risk rises rapidly when two or more risk factors are present. Hormone therapy in postmenopausal women increases risk of ischemic, but not hemorrhagic stroke, by 40-50%. Biomarkers of inflammation are associated with stroke risk. Other risk factors include certain lipids, physical inactivity, and low potassium diets. Although there has been improvement in the past decade, control of hypertension is inadequate in older women and many strokes could be prevented by better treatment of hypertension.

CONCLUSION

Death and disability from stroke can be reduced with modification, treatment, and better control of risk factors like hypertension, diabetes and atrial fibrillation.

Blood pressure reduction and cardiovascular prevention: meta-regression using ordered categorical (ordinal) event data

BACKGROUND

Blood pressure (BP)-lowering trials studying efficacy mostly assesses binary outcome events, for example stroke/no stroke. Analysis of ordered categorical vascular events (e.g. three levels: fatal stroke/nonfatal stroke/no stroke) provides information on severity and is more powerful statistically than analyses using binary data, as used in previous meta-regression analyses of BP lowering.

METHODS

Summary data on stroke, myocardial infarction, and combined vascular events were obtained from published BP-lowering trials. Ordinal and binary odds ratios were calculated. The relationship between the difference in BP and treatment odds ratio was assessed using meta-regression.

RESULTS

Thirty-eight trials involving 180 804 patients were included. A 'U' or 'J'-shaped relationship was found between on-treatment BP difference and three level ordinal stroke, ordinal myocardial infarction, and ordinal combined vascular outcome. Similar relationships were noted for binary stroke, myocardial infarction, and combined vascular outcome. Meta-regression curves for three level ordinal analyses were similar in shape and position to that for binary analyses.

CONCLUSIONS

Meta-regression using ordinal outcomes in hypertension trials is practical and gives comparable values for the odds ratio as found in analyses based on binary outcomes. However, trials and meta-analyses reporting ordinal outcomes provide additional information in particular that lowering BP reduces both the severity and frequency of fatal and recurrent stroke. Trials should report data so that ordinal analyses may be performed.

Target blood pressure for treatment of isolated systolic hypertension in the elderly: valsartan in elderly isolated systolic hypertension study

In this prospective, randomized, open-label, blinded end point study, we aimed to establish whether strict blood pressure control (<140 mm Hg) is superior to moderate blood pressure control (> or =140 mm Hg to <150 mm Hg) in reducing cardiovascular mortality and morbidity in elderly patients with isolated systolic hypertension. We divided 3260 patients aged 70 to 84 years with isolated systolic hypertension (sitting blood pressure 160 to 199 mm Hg) into 2 groups, according to strict or moderate blood pressure treatment. A composite of cardiovascular events was evaluated for > or =2 years. The strict control (1545 patients) and moderate control (1534 patients) groups were well matched (mean age: 76.1 years; mean blood pressure: 169.5/81.5 mm Hg). Median follow-up was 3.07 years. At 3 years, blood pressure reached 136.6/74.8 mm Hg and 142.0/76.5 mm Hg, respectively. The blood pressure difference between the 2 groups was 5.4/1.7 mm Hg. The overall rate of the primary composite end point was 10.6 per 1000 patient-years in the strict control group and 12.0 per 1000 patient-years in the moderate control group (hazard ratio: 0.89; [95% CI: 0.60 to 1.34]; P=0.38). In summary, blood pressure targets of <140 mm Hg are safely achievable in relatively healthy patients > or = 70 years of age with isolated systolic hypertension, although our trial was underpowered to definitively determine whether strict control was superior to less stringent blood pressure targets.

Maximizing scientific knowledge from randomized clinical trials

Trialists have an ethical and financial responsibility to plan and conduct clinical trials in a manner that will maximize the scientific knowledge gained from the trial. However, the amount of scientific information generated by randomized clinical trials in cardiovascular medicine is highly variable. Generation of trial databases and/or biobanks originating in large randomized clinical trials has successfully increased the knowledge obtained from those trials. At the 10th Cardiovascular Trialist Workshop, possibilities and pitfalls in designing and accessing clinical trial databases were discussed by a group of trialists. This review focuses on the arguments for conducting posttrial database studies and presents examples of studies in which posttrial knowledge generation has been substantial. Possible strategies to ensure successful trial database or biobank generation are discussed, in particular with respect to collaboration with the trial sponsor and to analytic pitfalls. The advantages of creating screening databases in conjunction with a given clinical trial are described; and finally, the potential for posttrial database studies to become a platform for training young scientists is outlined.

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.

Ischemic stroke in the elderly: an overview of evidence

Stroke mostly occurs in elderly people and patient outcomes after stroke are highly influenced by age. A better understanding of the causes of stroke in the elderly might have important practical implications not only for clinical management, but also for preventive strategies and future health-care policies. In this Review, we explore the evidence from both human and animal studies relating to the effect of old age-in terms of susceptibility, patient outcomes and response to treatment-on ischemic stroke. Several aging-related changes in the brain have been identified that are associated with an increase in vulnerability to ischemic stroke in the elderly. Furthermore, risk factor profiles for stroke and mechanisms of ischemic injury differ between young and elderly patients. Elderly patients with ischemic stroke often receive less-effective treatment and have poorer outcomes than younger individuals who develop this condition. Neuroprotective agents for ischemic stroke have been sought for decades but none has proved effective in humans. One contributing factor for this translational failure is that most preclinical studies have used young animals. Future research on ischemic stroke should consider age as a factor that influences stroke prevention and treatment, and should focus on the management of acute stroke in the elderly to reduce the incidence and improve outcomes in this vulnerable group.

The HDL hypothesis: does high-density lipoprotein protect from atherosclerosis?

There is unequivocal evidence of an inverse association between plasma high-density lipoprotein (HDL) cholesterol concentrations and the risk of cardiovascular disease, a finding that has led to the hypothesis that HDL protects from atherosclerosis. This review details the experimental evidence for this "HDL hypothesis". In vitro studies suggest that HDL has a wide range of anti-atherogenic properties but validation of these functions in humans is absent to date. A significant number of animal studies and clinical trials support an atheroprotective role for HDL; however, most of these findings were obtained in the context of marked changes in other plasma lipids. Finally, genetic studies in humans have not provided convincing evidence that HDL genes modulate cardiovascular risk. Thus, despite a wealth of information on this intriguing lipoprotein, future research remains essential to prove the HDL hypothesis correct.

Stopping the cardiovascular disease continuum: Focus on prevention

The cardiovascular disease continuum (CVDC) is a sequence of events, which begins from a host of cardiovascular risk factors that consists of diabetes mellitus, dyslipidemia, hypertension, smoking and visceral obesity. If it is not intervened with early, it inexorably progresses to atherosclerosis, coronary artery disease, myocardial infarction, left ventricular hypertrophy, and left ventricular dilatation, which lead to left ventricular diastolic or systolic dysfunction and eventually end-stage heart failure and death. Treatment intervention at any stage during its course will either arrest or delay its progress. In this editorial, the cardiovascular risk factors that initiate and perpetuate the CVDC are briefly discussed, with an emphasis on their early prevention or aggressive treatment.

Prognostic significance of visit-to-visit variability, maximum systolic blood pressure, and episodic hypertension

BACKGROUND

The mechanisms by which hypertension causes vascular events are unclear. Guidelines for diagnosis and treatment focus only on underlying mean blood pressure. We aimed to reliably establish the prognostic significance of visit-to-visit variability in blood pressure, maximum blood pressure reached, untreated episodic hypertension, and residual variability in treated patients.

METHODS

We determined the risk of stroke in relation to visit-to-visit variability in blood pressure (expressed as standard deviation [SD] and parameters independent of mean blood pressure) and maximum blood pressure in patients with previous transient ischaemic attack (TIA; UK-TIA trial and three validation cohorts) and in patients with treated hypertension (Anglo-Scandinavian Cardiac Outcomes Trial Blood Pressure Lowering Arm [ASCOT-BPLA]). In ASCOT-BPLA, 24-h ambulatory blood-pressure monitoring (ABPM) was also studied.

FINDINGS

In each TIA cohort, visit-to-visit variability in systolic blood pressure (SBP) was a strong predictor of subsequent stroke (eg, top-decile hazard ratio [HR] for SD SBP over seven visits in UK-TIA trial: 6.22, 95% CI 4.16-9.29, p<0.0001), independent of mean SBP, but dependent on precision of measurement (top-decile HR over ten visits: 12.08, 7.40-19.72, p<0.0001). Maximum SBP reached was also a strong predictor of stroke (HR for top-decile over seven visits: 15.01, 6.56-34.38, p<0.0001, after adjustment for mean SBP). In ASCOT-BPLA, residual visit-to-visit variability in SBP on treatment was also a strong predictor of stroke and coronary events (eg, top-decile HR for stroke: 3.25, 2.32-4.54, p<0.0001), independent of mean SBP in clinic or on ABPM. Variability on ABPM was a weaker predictor, but all measures of variability were most predictive in younger patients and at lower (

INTERPRETATION

Visit-to-visit variability in SBP and maximum SBP are strong predictors of stroke, independent of mean SBP. Increased residual variability in SBP in patients with treated hypertension is associated with a high risk of vascular events.

FUNDING

None.

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Key Words Collapse

MESH Headings

• Adult
• Aged
• Antihypertensive Agents/therapeutic use
• Blood Pressure
• Female
• Humans
• Hypertension/complications
• Hypertension/drug therapy
• Hypertension/physiopathology
• Ischemic Attack, Transient/complications
• Male
• Middle Aged
• Prognosis
• Risk Factors
• Stroke/etiology
• Stroke/prevention & control
• Systole

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Grants

• G0500987 Medical Research Council
• RP-PG-0606-1146 Department of Health
• British Heart Foundation

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Affiliation(s)

Peter M Rothwell Stroke Prevention Research Unit, University Department of Clinical Neurology, John Radcliffe Hospital, Headington, Oxford, UK.
Sally C Howard
Eamon Dolan
Eoin O'Brien
Joanna E Dobson
Bjorn Dahlöf
Peter S Sever
Neil R Poulter

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Collaborators Collapse

Effects of beta blockers and calcium-channel blockers on within-individual variability in blood pressure and risk of stroke

BACKGROUND

Analyses of some randomised trials show that calcium-channel blockers reduce the risk of stroke more than expected on the basis of mean blood pressure alone and that beta blockers are less effective than expected. We aimed to investigate whether the effects of these drugs on variability in blood pressure might explain these disparities in effect on stroke risk.

METHODS

The Anglo-Scandinavian Cardiac Outcomes Trial Blood Pressure Lowering Arm (ASCOT-BPLA) compared amlodipine-based regimens with atenolol-based regimens in 19 257 patients with hypertension and other vascular risk factors and the Medical Research Council (MRC) trial compared atenolol-based and diuretic-based regimens versus placebo in 4396 hypertensive patients aged 65-74 years. We expressed visit-to-visit variability of blood pressure during follow-up in the two trials as standard deviation (SD) and as transformations uncorrelated with mean blood pressure. For ASCOT-BPLA, we also studied within-visit variability and variability on 24 h ambulatory blood-pressure monitoring (ABPM).

RESULTS

In ASCOT-BPLA, group systolic blood pressure (SBP) SD was lower in the amlodipine group than in the atenolol group at all follow-up visits (p<0.0001), mainly because of lower within-individual visit-to-visit variability. Within-visit and ABPM variability in SBP were also lower in the amlodipine group than in the atenolol group (all p<0.0001). Analysis of changes from baseline showed that variability decreased over time in the amlodipine group and increased in the atenolol group. The lower risk of stroke in the amlodipine group (hazard ratio 0.78, 95% CI 0.67-0.90) was partly attenuated by adjusting for mean SBP during follow-up (0.84, 0.72-0.98), but was abolished by also adjusting for within-individual SD of clinic SBP (0.99, 0.85-1.16). Findings were similar for coronary events. In the ABPM substudy, reduced variability in daytime SBP in the amlodipine group (p<0.0001) partly accounted for the reduced risk of vascular events, but reduced visit-to-visit variability in clinic SBP had a greater effect. In the MRC trial, group SD SBP and all measures of within-individual visit-to-visit variability in SBP were increased in the atenolol group compared with both the placebo group and the diuretic group during initial follow-up (all p<0.0001). Subsequent temporal trends in variability in blood pressure during follow-up in the atenolol group correlated with trends in stroke risk.

INTERPRETATION

The opposite effects of calcium-channel blockers and beta blockers on variability of blood pressure account for the disparity in observed effects on risk of stroke and expected effects based on mean blood pressure. To prevent stroke most effectively, blood-pressure-lowering drugs should reduce mean blood pressure without increasing variability; ideally they should reduce both.

Improving vascular function in hypertension: potential benefits of combination therapy with amlodipine and renin-angiotensin-aldosterone system blockers

Hypertension is characterized by endothelial dysfunction and increased risk for adverse cardiovascular outcomes. In addition to lowering blood pressure, the calcium-channel blocker amlodipine and blockers of the renin-angiotensin-aldosterone system (angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor blockers) may further reduce cardiovascular risk by improving endothelial function when used alone or in combination. In fact, the beneficial effects of the combination of amlodipine and a renin-angiotensin-aldosterone system blocker on endothelial function have been found to be greater than the effect of either drug alone, likely due to additive effects on nitric oxide activity. This review summarizes the observed effects of these agents on endothelial function and the complementary mechanisms by which they act, thus providing rationale (beyond blood pressure benefits) for their use in combination.

Primary and secondary prevention of cardiovascular disease in older adults: a status report

This article reviews cardiovascular disease (CVD) prevention in older patients, highlighting results from recent clinical studies related to primary and secondary prevention. Many of these studies demonstrated greater absolute reductions in major cardiovascular events among older, higher-risk populations compared with younger patients. Guideline recommendations for CVD risk factor modification are also reviewed with emphasis on issues pertaining to the older adult population.

Geriatric nephrology: responding to a growing challenge

Changing demographics of the global population predict that the number of people age 65 years or greater will triple over the coming decades. Because the incidence and prevalence of kidney disease increase with advancing age, nephrologists will be increasingly confronted with a population of patients who are elderly and have a large number of comorbid conditions requiring ongoing care. Furthermore, it is increasingly understood that aging leads to its own unique aspects of nephrologic diagnosis and treatment. Although it is known that elderly patients constitute a group with special needs and present unique challenges to the nephrologist, traditional nephrology fellowship training has not included a focus on the geriatric population. In response to this need for greater education and awareness, the American Society of Nephrology has initiated a program of educational activities in geriatric nephrology and has chartered a specific advisory council. The priority being given to geriatric nephrology is a hopeful sign that issues such as treatment options, the efficacy of treatments, and their effect on quality of life for the elderly patient with kidney disease will be improved in the coming years.

Antihypertensive drug persistence and compliance among newly treated elderly hypertensives in ontario

BACKGROUND

Poor medication-taking behaviors are important considerations in the management of hypertension.

METHODS

We conducted a retrospective cohort study addressing antihypertensive drug persistence and compliance by linking 4 administrative databases and a province-wide clinical database in Ontario, Canada, to derive a cohort of elderly hypertensive patients, aged 66 years or more, who had received a new prescription for an antihypertensive agent between 1997 and 2005 to determine trends across years and associations with drug class and sociodemographic and other factors.

RESULTS

Our cohort consisted of 207,473 patients (58.4% were women, mean age 74.2 years, 73.1% were comorbid-free), 41,236 of whom had diabetes. Persistence and compliance increased between 1997 and 2005 (all P<.02) and were greater in those of higher socioeconomic status but lesser in urban residents (all P<.0001). Persistence was lower in comorbid-free patients and greater in older patients, whereas compliance was lower in older patients and greater in women and comorbid-free patients (all P<.0001). Significant differences between the drug classes emerged with initial prescriptions for all drug classes showing greater therapy and class persistence compared with diuretics (all P<.0001). Angiotensin-converting enzyme inhibitors showed the best therapy persistence and compliance, and beta-blockers showed the worst compliance (all P<.0001).

CONCLUSION

Our data provide evidence of an overall improvement in antihypertensive drug compliance and persistence across years, as well as significant differences across drug classes and other patient-level factors. Awareness of such factors could translate into concerted efforts at optimizing medication-taking behaviors among newly diagnosed elderly hypertensive patients.

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.

Management of essential hypertension

INTRODUCTION

Epidemiological studies have unequivocally shown that hypertension (HT)is a major cardiovascular (CV) risk factor and that a direct linear relationship exists between the severity of the blood pressure (BP) elevation and the occurrence of CV events.

AREAS OF AGREEMENT AND CONTROVERSY

The beneficial effects of the BP-lowering interventions have been recognized since a number of years. These include not only the reduction in CV morbidity and mortality but also the regression (or the delay of progression) of HT-related end-organ damage, such as left ventricular hypertrophy, vascular remodelling, endothelial dysfunction and renal damage. Along with these well-established features, antihypertensive drug treatment still faces a number of unmet goals and unanswered questions, such as the target BP values to achieve in high-risk patients, the threshold of treatment in low-risk patients as well as the choice of the therapeutic approach more likely to offer greater CV protection.

CONCLUSION

Despite unmet goals, antihypertensive treatment has provided throughout the years successful results. Future efforts will be need to achieve a better BP control in the population and thus to obtain a greater CV protection.

Association of hypertension treatment and control with all-cause and cardiovascular disease mortality among US adults with hypertension

BACKGROUND

Clinical trials have provided convincing evidence that blood pressure (BP) lowering treatment reduces the risk of cardiovascular disease (CVD) and total mortality. The objective of this study was to examine the association of hypertension treatment, control, and BP indexes with all-cause and cardiovascular mortality among US adults with hypertension.

METHODS

Persons aged > or =18 years from the Third National Health and Nutrition Examination Survey (NHANES III) were identified as hypertensives based on a BP > or =140/90 mm Hg or current treatment for hypertension. Vital status in 2006 was ascertained by passive follow-up using the National Death Index. Cox regression models were used to assess correlates of survival.

RESULTS

At baseline, 52% of hypertensive adults reported currently taking prescription medicine for high BP and 38% of treated persons had BP controlled. Compared to treated controlled hypertensives, treated uncontrolled hypertensives had a 1.57-fold (95% confidence interval (CI) 1.28-1.91) and 1.74-fold (95% CI 1.36-2.22) risk of all-cause and cardiovascular mortality; untreated hypertensives had a 1.34-fold (95% CI 1.12-1.62) and 1.37-fold (95% CI 1.04-1.81) risk of all-cause and cardiovascular mortality, respectively. The association persisted after further excluding persons with pre-existing hypertension comorbidities. Mortality risk was linearly increased with systolic BP (SBP), pulse pressure (PP), and mean arterial pressure (MBP), whereas diastolic BP (DBP) was not a significant predictor of cardiovascular mortality overall. No significant associations were observed between drug classes and mortality risk.

CONCLUSIONS

This study indicates that uncontrolled and untreated hypertension was associated with increased risk of total and cardiovascular mortality among the general hypertensive population.