Endocrine and haemodynamic changes in resistant hypertension, and blood pressure responses to spironolactone or amiloride: the PATHWAY-2 mechanisms substudies

BACKGROUND

In the PATHWAY-2 study of resistant hypertension, spironolactone reduced blood pressure substantially more than conventional antihypertensive drugs. We did three substudies to assess the mechanisms underlying this superiority and the pathogenesis of resistant hypertension.

METHODS

PATHWAY-2 was a randomised, double-blind crossover trial done at 14 UK primary and secondary care sites in 314 patients with resistant hypertension. Patients were given 12 weeks of once daily treatment with each of placebo, spironolactone 25-50 mg, bisoprolol 5-10 mg, and doxazosin 4-8 mg and the change in home systolic blood pressure was assessed as the primary outcome. In our three substudies, we assessed plasma aldosterone, renin, and aldosterone-to-renin ratio (ARR) as predictors of home systolic blood pressure, and estimated prevalence of primary aldosteronism (substudy 1); assessed the effects of each drug in terms of thoracic fluid index, cardiac index, stroke index, and systemic vascular resistance at seven sites with haemodynamic monitoring facilities (substudy 2); and assessed the effect of amiloride 10-20 mg once daily on clinic systolic blood pressure during an optional 6-12 week open-label runout phase (substudy 3). The PATHWAY-2 trial is registered with EudraCT, number 2008-007149-30, and ClinicalTrials.gov, number NCT02369081.

FINDINGS

Of the 314 patients in PATHWAY-2, 269 participated in one or more of the three substudies: 126 in substudy 1, 226 in substudy 2, and 146 in substudy 3. Home systolic blood pressure reduction by spironolactone was predicted by ARR (r²=0·13, p<0·0001) and plasma renin (r²=0·11, p=0·00024). 42 patients had low renin concentrations (predefined as the lowest tertile of plasma renin), of which 31 had a plasma aldosterone concentration greater than the mean value for all 126 patients (250 pmol/L). Thus, 31 (25% [95% CI 17-33]) of 126 patients were deemed to have inappropriately high aldosterone concentrations. Thoracic fluid content was reduced by 6·8% from baseline (95% CI 4·0 to 8·8; p<0·0001) with spironolactone, but not other treatments. Amiloride (10 mg once daily) reduced clinic systolic blood pressure by 20·4 mm Hg (95% CI 18·3-22·5), compared with a reduction of 18·3 mm Hg (16·2-20·5) with spironolactone (25 mg once daily). No serious adverse events were recorded, and adverse symptoms were not systematically recorded after the end of the double-blind treatment. Mean plasma potassium concentrations increased from 4·02 mmol/L (95% CI 3·95-4·08) on placebo to 4·50 (4·44-4·57) on amiloride (p<0·0001).

INTERPRETATION

Our results suggest that resistant hypertension is commonly a salt-retaining state, most likely due to inappropriate aldosterone secretion. Mineralocorticoid receptor blockade by spironolactone overcomes the salt retention and resistance of hypertension to treatment. Amiloride seems to be as effective an antihypertensive as spironolactone, offering a substitute treatment for resistant hypertension.

FUNDING

British Heart Foundation and UK National Institute for Health Research.

Saving lives: Long-term morbidity and mortality trials with selective angiotensin receptor blocker therapy

Prospective randomised trials have demonstrated convincingly the benefits of drug treatment of hypertension. Treatment with conventional antihypertensive agents reduces the incidence of cardiovascular events by about that which would be expected from epidemiological data for the achieved difference in blood pressure. Newer agents, such as angiotensin II receptor blockers, have potential for benefits beyond blood pressure reduction. This rationale is under evaluation in a number of long-term morbidity and mortality trials which will report over the next few years, with the largest, VALUE, due to provide results in 2004. The findings from these trials will be decisive in determining the future role of this important new class of drugs.

Contrasting mortality risks among subgroups of treated hypertensive patients developing new-onset diabetes

AIMS

Hypertension and diabetes mellitus (DM) frequently cluster together and synergistically increase cardiovascular risk. Among those who develop DM during treatment for hypertension (new-onset diabetes, NOD), it is unclear whether NOD reflects a separate entity associated with increased risk or merely reflects accelerated presentation of DM.

METHODS AND RESULTS

We analysed data on 15 089 hypertensive patients attending the Glasgow Blood Pressure Clinic. The date at first hospital encounter either with diagnosis of diabetes or prescription of anti-hyperglycaemic medication were considered as the onset of diabetes. Cox proportional hazard models (including propensity score matching) were employed to study associations between diabetes status, early and late NOD (diagnosis <10 years or >10 years from first clinic visit) and cause-specific mortality. There were 2516 patients (16.7%) with DM, of whom 1862 (12.3%) had NOD [early NOD = 705 (4.6%); late NOD = 1157 (7.6%)]. The incidence rate of NOD was 8.2 per 1000 person-years. The total time at risk was 239 929 person-years [median survival: 28.1 years (inter-quartile range: 16.2-39.9)]. Compared with non-diabetic individuals, prevalent DM [hazard ratio (HR) = 1.8, 95% confidence interval (CI): 1.4-2.2] and time varying NOD status (HR: 1.09, 95% CI: 1.06-1.17) were associated with increased adjusted all-cause mortality. Early NOD (HR: 1.39, 95% CI: 1.2-1.6) was associated with increased in mortality risk, but not late NOD (HR: 0.92, 95% CI: 0.83-1.01). Results were consistent in the propensity score matched analyses.

CONCLUSION

Although 1-in-8 hypertensive patients develop NOD, mortality is increased only in the 1-in-20 who develop early NOD. Further studies are warranted to determine if early identification of such individuals should provide an alert for intensification of therapeutic interventions.

Acetaminophen use and risk of myocardial infarction and stroke in a hypertensive cohort

Recent data suggest that self-reported acetaminophen use is associated with increased risk of cardiovascular events and that acetaminophen causes a modest blood pressure rise. There are no randomized trials or studies using verified prescription data of this relationship. We aimed to assess the relationship between verified acetaminophen prescription data and risk of myocardial infarction or stroke in patients with hypertension. We performed a retrospective data analysis using information contained within the UK Clinical Research Practice Datalink. Multivariable Cox proportional hazard models were used to estimate hazard ratios for myocardial infarction (primary end point), stroke, and any cardiovascular event (secondary end points) associated with acetaminophen use during a 10-year period. Acetaminophen exposure was a time-dependent variable. A propensity-matched design was also used to reduce potential for confounding. We included 24,496 hypertensive individuals aged ≥ 65 years. Of these, 10,878 were acetaminophen-exposed and 13,618 were not. There was no relationship between risk of myocardial infarction, stroke, or any cardiovascular event and acetaminophen exposure on adjusted analysis (hazard ratio, 0.98; 95% confidence interval, 0.76-1.27; hazard ratio, 1.09; 95% confidence interval, 0.86-1.38; and hazard ratio, 1.17; 95% confidence interval, 0.99-1.37; respectively). Results in the propensity-matched sample (n=4000 per group) and when men and women were analyzed separately were similar. High-frequency users (defined as receiving a prescription for >75% of months) were also not at increased risk. After allowance for potentially confounding variables, the use of acetaminophen was not associated with an increased risk of myocardial infarction or stroke in a large cohort of hypertensive patients.

Serum Chloride Is an Independent Predictor of Mortality in Hypertensive Patients

Chloride (Cl − ) is the major extracellular anion in the body, accompanying sodium (Na + ), and is primarily derived from dietary sources. Data suggest that increased dietary Cl − intake increases blood pressure, yet paradoxically, higher serum Cl − appears associated with lower mortality and cardiovascular risk. This implies that serum Cl − also reflects risk pathways independent of blood pressure, serum Na + , and bicarbonate (HCO 3 − ). We analyzed 12 968 hypertensive individuals followed up for 35 years, using Cox proportional hazards model to test whether baseline serum Cl − was an independent predictor of mortality. To distinguish the effect of Cl − from Na + and HCO 3 − , we adjusted for these electrolytes and also performed the analysis stratified by Na + /HCO 3 − and Cl − levels. Generalized estimating equation was used to determine the effect of baseline Cl − on follow-up blood pressure. The total time at risk was 197 101 person-years. The lowest quintile of serum Cl − (<100 mEq/L) was associated with a 20% higher mortality (all-cause, cardiovascular and noncardiovascular) compared with the remainder of the subjects. A 1 mEq/L increase in serum Cl − was associated with a 1.5% (hazard ratio, 0.985; 95% confidence interval, 0.98–0.99) reduction in all-cause mortality, after adjustment for baseline confounding variables and Na + , K + , and HCO3 − levels. The group with Na + >135 and Cl − >100 had the best survival, and compared with this group, the Na + >135 and Cl − <100 group had significantly higher mortality (hazard ratio, 1.21; 95% confidence interval, 1.11–1.31). Low, not high Serum Cl − (<100 mEq/L), is associated with greater mortality risk independent of obvious confounders. Further studies are needed to elucidate the relation between Cl − and risk.

Long-term and ultra long-term blood pressure variability during follow-up and mortality in 14,522 patients with hypertension

Recent evidence indicates that long-term visit-to-visit blood pressure variability (BPV) may be an independent cardiovascular risk predictor. The implication of this variability in hypertension clinical practice is unclear. BPV as average real variability (ARV) was calculated in 14,522 treated patients with hypertension in 4 time frames: year 1 (Y1), years 2 to 5 (Y2-5), years 5 to 10 (Y5-10), and years >10 (Y10+) from first clinic visit. Cox proportional hazards models for cause-specific mortality were used in each time frame separately for long-term BPV, across time frames based on ultra long-term BPV, and within each time frame stratified by mean BP. ARV in systolic blood pressure (SBP), termed ARV(SBP), was higher in Y1 (21.3±11.9 mm Hg) in contrast to Y2-5 (17.7±9.9 mm Hg), Y5-10 (17.4±9.6 mm Hg), and Y10+ (16.8±8.5 mm Hg). In all time frames, ARV(SBP) was higher in women (P<0.01) and in older age (P<0.001), chronic kidney disease (P<0.01), and prevalent cardiovascular disease (P<0.01). Higher long-term and ultra long-term BPV values were associated with increased mortality (all-cause, cardiovascular, and noncardiovascular mortality; P for trend, <0.001). This relationship was also evident in subgroups with mean SBP<140 mm Hg in all time frames. Monitoring BPV in clinical practice may facilitate risk reduction strategies by identifying treated hypertensive individuals at high risk, especially those with BP within the normal range.

Noninvasive cardiac event monitoring to detect atrial fibrillation after ischemic stroke: a randomized, controlled trial

BACKGROUND AND PURPOSE

Atrial fibrillation (AF) elevates risk of recurrent stroke but is incompletely identified by standard investigation after stroke, though detection rates correlate with monitoring duration. We hypothesized that 7 days of noninvasive cardiac-event monitoring early after stroke would accelerate detection of AF and thus uptake of effective therapy.

METHODS

We performed a pragmatic randomized trial with objective outcome assessment among patients presenting in sinus rhythm with no AF history, within 7 days of ischemic stroke symptom onset. Patients were randomized to standard practice investigations (SP) to detect AF, or SP plus additional monitoring (SP-AM). AM comprised 7 days of noninvasive cardiac-event monitoring reported by an accredited cardiac electrocardiology laboratory. Primary outcome was detection of AF at 14 days.

RESULTS

One-hundred patients were enrolled from 2 centers. Within 14 days of stroke, sustained paroxysms of AF were detected in 18% of patients undergoing SP-AM versus 2% undergoing SP (P<0.05). Paroxysms of any-duration were detected in 44% of patients undergoing SP-AM versus 4% undergoing SP (P<0.001). These differences persisted at 90 days. Anticoagulant therapy was commenced within 14 days in 16% of SP-AM patients versus none randomized to SP (P<0.01). This difference persisted to 90 days (22% versus 6%; P<0.05).

CONCLUSIONS

Routine noninvasive cardiac-event monitoring after acute stroke enhances detection of paroxysmal AF and early anticoagulation. Extended monitoring should be offered to all eligible patients soon after acute stroke. Guidelines on investigation for AF in stroke patients could be strengthened.

CLINICAL TRIAL REGISTRATION URL

http://www.controlled-trials.com/isrctn/. Unique identifier: ISRCTN97412358.

Blood pressure response to patterns of weather fluctuations and effect on mortality

Very few studies have looked at longitudinal intraindividual blood pressure responses to weather conditions. There are no data to suggest that specific response to changes in weather will have an impact on survival. We analyzed >169 000 clinic visits of 16 010 Glasgow Blood Pressure Clinic patients with hypertension. Each clinic visit was mapped to the mean West of Scotland monthly weather (temperature, sunshine, rainfall) data. Percentage change in blood pressure was calculated between pairs of consecutive clinic visits, where the weather alternated between 2 extreme quartiles (Q(1)-Q(4) or Q(4)-Q(1)) or remained in the same quartile (Q(n)-Q(n)) of each weather parameter. Subjects were also categorized into 2 groups depending on whether their blood pressure response in Q(1)-Q(4) or Q(4)-Q(1) were concordant or discordant to Q(n)-Q(n). Generalized estimating equations and Cox proportional hazards model were used to model the effect on longitudinal blood pressure and mortality, respectively. Q(n)-Q(n) showed a mean 2% drop in blood pressure consistently, whereas Q(4)-Q(1) showed a mean 2.1% and 1.6% rise in systolic and diastolic blood pressure, respectively. However, Q(1)-Q(4) did not show significant changes in blood pressure. Temperature-sensitive subjects had significantly higher mortality (1.35 [95% confidence interval, 1.06-1.71]; P=0.01) and higher follow-up systolic blood pressure (1.85 [95% confidence interval, 0.24-3.46]; P=0.02) compared with temperature-nonsensitive subjects. Blood pressure response to temperature may be one of the underlying mechanisms that determine long-term blood pressure variability. Knowing a patient's blood pressure response to weather can help reduce unnecessary antihypertensive treatment modification, which may in turn increase blood pressure variability and, thus, risk.

Abstract 639: Blood Pressure Response To Patterns Of Weather Fluctuations And Effect On Mortality

Background: Very few studies have looked at longitudinal BP changes in relation to weather variation. There is no data to suggest that specific BP response to changes in weather have an impact on survival.

METHODS: We analysed >169000 clinic visits of 16000 Glasgow BP Clinic hypertensive patients. Each clinic visit was mapped to the mean West of Scotland monthly weather (temperature, sunshine, rainfall) from meteorological data. Analyses were restricted to pairs of consecutive clinic visits where the weather alternated between two extreme quartiles (Q1->Q4 or Q4->Q1) or remained in the same quartile (Qn->Qn) of each weather parameter. The BP phenotype analysed was the percent change in SBP and DBP between two consecutive clinic measurements at least 30 days apart and within each year. The %ΔBP between groups were tested using paired-T tests. Subjects were categorised into two groups depending on Q1->Q4 or Q4->Q1 BP response compared to Qn->Qn (concordant or discordant). Generalised estimating equations and Cox proportional hazards model were used to model the effect on longitudinal BP and mortality respectively.

Results: For temperature, visits Qn->Qn showed a mean 2% drop in BP consistently while Q4->Q1 showed a mean 4% rise in SBP and Q1->Q4 elicited variable changes in BP around 0. Compared to subjects with a concordant BP response to temperature, those who showed a discordant response had significantly higher mortality (1.35 [95% CI :1.06-.71];p=0.01) and higher follow-up SBP (1.85 [0.24-3.46]; p=0.02).

Conclusions: Variation in weather has a complex relationship to longitudinal BP and response to weather fluctuations is a predictor of long-term risk and BP control.

Abstract 433: Serum Chloride is an Independent and Robust Predictor of Mortality Than Serum Sodium, Potassium or Bicarbonate in Hypertensive Patients

Objectives: Extremes of serum Na + , K + and HCO 3 have been associated with poorer outcomes. The role of serum Cl - has been largely considered to be linked to serum Na + and HCO 3 levels.

Design and Methods: We studied the association of serum and other serum electrolytes in relation to mortality outcomes in 13,415 hypertensive patients attending the Glasgow Blood Pressure Clinic (GBPC) with serum Cl - assessed at the registration visit. Cox proportional hazards (Cox-PH) models were used for survival analysis. To determine whether Cl - effects are independent of low serum sodium, we performed the analysis in subjects with Na + >135 and stratified by Na + and Cl - levels.

Results: The total time at risk was 197,101 person years during which 3,373 all-cause deaths occurred. Compared to quintile 1 (Cl - <=100), each higher quintile of Cl - was associated with lower mortality (H.R.[95%C.I.]0.82[0.74-0.90];0.79[0.71-0.87];0.79[0.70-0.89];0.80[0.68-0.93]) after adjustment for all conventional risk factors, other serum electrolytes and diuretic use (Figure-1). In the subset with Na + >135, each unit increase in Cl - was associated with a 3% reduction in mortality(H.R =0.97 CI:0.96-0.98). Finally subjects with Na + >135&Cl - >100(reference) had the best survival and those with Na + <135 and Cl - <100 the poorest survival. The group with normal Na + >135 and Cl - <100 had significantly higher mortality than the reference group (1.21[1.11-1.31]).

Conclusion: Serum Cl - independently predicts mortality outcomes in the hypertensive population irrespective of serum Na + , K + and HCO 3 levels.

Hematocrit predicts long-term mortality in a nonlinear and sex-specific manner in hypertensive adults

Hematocrit has been inconsistently reported to be a risk marker of cardiovascular morbidity and mortality. The Glasgow Blood Pressure Clinic Study cohort included 10951 hypertensive patients, who had hematocrit measured at their initial clinic visit and followed for ≤35 years. Cox proportional hazards models were used to estimate hazard ratios for all-cause, cardiovascular, ischemic heart disease, stroke, and noncardiovascular mortality. There were 3484 deaths over a follow-up period of 173245 person-years. Hematocrit was higher in men (median, 0.44; interquartile range, 0.42-0.47) than in women (median, 0.41; interquartile range, 0.38-0.43). The lowest risk for all-cause mortality was seen in quartile 2 for men (range, 0.421-0.440) and women (range, 0.381-0.400). Compared with quartile 2, the adjusted hazard ratios for quartiles 1, 3, and 4 were, respectively, 1.11 (range, 0.97-1.28), 1.19 (range, 1.04-1.37), and 1.22 (range, 1.06-1.39) in men and 1.17 (range, 1.01-1.36), 0.97 (range, 0.83-1.13), and 1.19 (range, 1.04-1.37) in women. Men showed a J-shaped pattern for cardiovascular mortality and a linear pattern for noncardiovascular mortality in cause-specific analysis, whereas in women a U-shaped pattern was observed for noncardiovascular mortality only. Higher baseline hematocrit was associated with higher on-treatment blood pressure during follow-up. Baseline hematocrit did not affect the time to reach target blood pressure. The increased risk of death attributed to higher hematocrit was seen in men and women irrespective of their achievement of target blood pressure, indicating that the risk is independent of the effect of hematocrit on blood pressure. Hypertensive patients with hematocrit levels outside of the sex-specific reference ranges identified in this study should be targeted for more aggressive blood pressure and cardiovascular risk reduction treatment.

Usefulness of heart rate to predict cardiac events in treated patients with high-risk systemic hypertension

A high heart rate (HR) predicts future cardiovascular events. We explored the predictive value of HR in patients with high-risk hypertension and examined whether blood pressure reduction modifies this association. The participants were 15,193 patients with hypertension enrolled in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial and followed up for 5 years. The HR was assessed from electrocardiographic recordings obtained annually throughout the study period. The primary end point was the interval to cardiac events. After adjustment for confounders, the hazard ratio of the composite cardiac primary end point for a 10-beats/min of the baseline HR increment was 1.16 (95% confidence interval 1.12 to 1.20). Compared to the lowest HR quintile, the adjusted hazard ratio in the highest quintile was 1.73 (95% confidence interval 1.46 to 2.04). Compared to the pooled lower quintiles of baseline HR, the annual incidence of primary end point in the top baseline quintile was greater in each of the 5 study years (all p <0.05). The adjusted hazard ratio for the primary end point in the highest in-trial HR heart rate quintile versus the lowest quintile was 1.53 (95% confidence interval 1.26 to 1.85). The incidence of primary end points in the highest in-trial HR group compared to the pooled 4 lower quintiles was 53% greater in patients with well-controlled blood pressure (p <0.001) and 34% greater in those with uncontrolled blood pressure (p = 0.002). In conclusion, an increased HR is a long-term predictor of cardiovascular events in patients with high-risk hypertension. This effect was not modified by good blood pressure control. It is not yet known whether a therapeutic reduction of HR would improve cardiovascular prognosis.

Direct-acting vasodilators

KEY POINTS AND PRACTICAL RECOMMENDATIONS: •  Hydralazine and minoxidil act by dilating resistance arterioles, thus reducing peripheral resistance, with no dilating effect on the venous side of the circulation. •  There is a baroreflex-mediated venoconstriction, resulting in an increase in venous return to the heart, along with a direct catecholamine-mediated positive inotropic and chronotropic stimulation of the heart. •  Hydralazine therapy is usually combined with a sympathetic inhibitor to prevent expression of this reflex, as well as with a diuretic agent to prevent sodium retention caused by reduction in renal perfusion pressure. •  Hydralazine is indicated in the long-term therapy of essential hypertension, in the short-term therapy of pregnancy-induced hypertension and eclampsia, and in the therapy of hypertensive crisis. •  Adverse effects include the anticipated tachycardia, fluid retention, and headache, caused by the vasodilation, especially in the early days of therapy, but may frequently be prevented by the concomitant use of a β-blocker. •  As with other drugs that are N-acetylated, there is a low risk of lupus-like syndrome with high doses and long-term use. •  Because of the severity of adverse effects with minoxidil, its usage is limited to persons with severe hypertension unresponsive to other treatments. •  Hirsutism, a common side effect of minoxidil, is particularly bothersome in women and reverses in a few months after discontinuation. •  Sodium nitroprusside is used in the intensive care setting to lower pressure in hypertensive crisis or to treat severe left ventricular failure, particularly valuable when elevated pressure or severe left ventricular failure threatens the patient's survival. •  Although nitrates have not achieved widespread use as antihypertensive agents, they are effective in producing sustained blood pressure (BP) reductions when added to other antihypertensive regimens.

Long-Term Outcome following Attendance at a Transient Ischemic Attack Clinic

Background and purpose

Many patients who attend transient ischemic attack clinics have a noncerebrovascular diagnosis. The long-term outcomes in this group are not well described. We evaluated these in a cohort referred to a transient ischemic attack clinic with a suspected transient ischemic attack.

Methods

Patients were clinically classified as having stroke or a transient ischemic attack or a noncerebrovascular diagnosis (nontransient ischemic attack). Follow-up was via electronic record linkage. The primary endpoint was cardiovascular death or a major cardiovascular event. Secondary outcomes included incident neurological disease (excluding stroke or transient ischemic attack) and the need for permanent pacemaker insertion. Outcomes in the transient ischemic attack and nontransient ischemic attack cohorts were compared using Cox's proportional hazards models. Mortality outcomes were further compared with those in a contemporary control group of individuals with hypertension.

Results

Of the 3533 patients who attended the transient ischemic attack clinic, 53·5% had a transient ischemic attack. Of these, 769 (40·7%) suffered a cardiovascular endpoint, compared with 458 (27·9%) with a nontransient ischemic attack (hazard ratio 1·53, 95% confidence interval 1·36–1·72). The risk remained higher but was attenuated following adjustment (hazard ratio 1·21, 95% confidence interval 1·05–1·41). Cardiovascular mortality in both groups was higher than that in hypertensive controls. The risk of a subsequent nonstroke neurological event was higher in those without a transient ischemic attack.

Conclusions

Patients without a transient ischemic attack referred to a transient ischemic attack clinic have a high risk of future vascular events that exceeds risk in a cohort with hypertension. All patients attending transient ischemic attack clinics should undergo assessment of their cardiovascular risk and the use of methods to reduce this risk should be explored.

Aliskiren and the calcium channel blocker amlodipine combination as an initial treatment strategy for hypertension control (ACCELERATE): a randomised, parallel-group trial

BACKGROUND

Short-term studies have suggested that the use of initial combination therapy for the control of blood pressure improves early effectiveness. We tested whether a combination of aliskiren and amlodipine is superior to each monotherapy in early control of blood pressure without excess of adverse events, and if initial control by monotherapy impairs subsequent control by combination therapy.

METHODS

We did a double-blind, randomised, parallel-group, superiority trial at 146 primary and secondary care sites in ten countries, with enrolment from Nov 28, 2008, to July 15, 2009. Patients eligible for enrolment had essential hypertension, were aged 18 years or older, and had systolic blood pressure between 150 and 180 mm Hg. Patients were randomly assigned (1:1:2) to treatment with 150 mg aliskiren plus placebo, 5 mg amlodipine plus placebo, or 150 mg aliskiren plus 5 mg amlodipine. Random assignment was through a central interactive voice response system and treatment allocation was masked from the patients. From 16-32 weeks, all patients received combination therapy with 300 mg aliskiren plus 10 mg amlodipine. Our primary endpoints, assessed on an intention-to-treat basis (ie, in patients who received the allocated treatment), were the adjusted mean reduction in systolic blood pressure from baseline over 8 to 24 weeks, and then the final reduction at 24 weeks. This trial is registered with ClinicalTrials.gov, number NCT00797862.

FINDINGS

318 patients were randomly assigned to aliskiren, 316 to amlodipine, and 620 to aliskiren plus amlodipine. 315 patients initially allocated to aliskiren, 315 allocated to amlodipine, and 617 allocated to aliskiren plus amlodipine were available for analysis. Patients given initial combination therapy had a 6·5 mm Hg (95% CI 5·3 to 7·7) greater reduction in mean systolic blood pressure than the monotherapy groups (p<0·0001). At 24 weeks, when all patients were on combination treatment, the difference was 1·4 mm Hg (95% CI -0·05 to 2·9; p=0·059). Adverse events caused withdrawal of 85 patients (14%) from the initial aliskiren plus amlodipine group, 45 (14%) from the aliskiren group, and 58 (18%) from the amlodipine group. Adverse events were peripheral oedema, hypotension, or orthostatic hypotension.

INTERPRETATION

We believe that routine initial reduction in blood pressure (>150 mm Hg) with a combination such as aliskiren plus amlodipine can be recommended.

FUNDING

Novartis Pharma AG.

The unintended consequences of clinical trials regulations

Alex McMahon and colleagues critique the International Conference on Harmonisation (ICH) guidance on good clinical practice (GCP), arguing that it is having a disastrous effect on noncommerical randomized clinical trials in Europe.

Drug Insight: eplerenone, a mineralocorticoid-receptor antagonist

Increasing recognition of the role of aldosterone in cardiovascular disease has been supported by a significant body of evidence from animal models. This evidence has been translated into clinical practice, and large-scale, randomized, placebo-controlled trials have confirmed the beneficial effects of mineralocorticoid blockade in patients with heart failure. As a consequence, there has been a resurgence in the use of mineralocorticoid-receptor antagonists in clinical practice that has prompted the search for a potent and specific antagonist without the sexual side effects of spironolactone. Eplerenone, a mineralocorticoid-receptor antagonist with minimal binding to the progesterone and androgen receptors, is now licensed for treatment of heart failure in Europe and heart failure and hypertension in the US; it has also been proposed as a treatment for a variety of cardiovascular conditions. This article reviews the current concepts of the actions of aldosterone at a cellular level. Recent findings regarding its role as a cardiovascular hormone, both in animal models and human studies, are discussed. We also describe the development of mineralocorticoid-receptor blockers following the isolation of aldosterone and discuss the subsequent search for a specific mineralocorticoid antagonist. In addition we detail the effects of eplerenone in a number of clinical situations and outline its potential future applications.

Prediction of cardiovascular outcome by estimated glomerular filtration rate and estimated creatinine clearance in the high-risk hypertension population of the VALUE trial

BACKGROUND

Reduced renal function is predictive of poor cardiovascular outcomes but the predictive value of different measures of renal function is uncertain.

METHODS

We compared the value of estimated creatinine clearance, using the Cockcroft-Gault formula, with that of estimated glomerular filtration rate (GFR), using the Modification of Diet in Renal Disease (MDRD) formula, as predictors of cardiovascular outcome in 15 245 high-risk hypertensive participants in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial. For the primary end-point, the three secondary end-points and for all-cause death, outcomes were compared for individuals with baseline estimated creatinine clearance and estimated GFR < 60 ml/min and > or = 60 ml/min using hazard ratios and 95% confidence intervals. Coronary heart disease, left ventricular hypertrophy, age, sex and treatment effects were included as covariates in the model.

RESULTS

For each end-point considered, the risk in individuals with poor renal function at baseline was greater than in those with better renal function. Estimated creatinine clearance (Cockcroft-Gault) was significantly predictive only of all-cause death [hazard ratio = 1.223, 95% confidence interval (CI) = 1.076-1.390; P = 0.0021] whereas estimated GFR was predictive of all outcomes except stroke. Hazard ratios (95% CIs) for estimated GFR were: primary cardiac end-point, 1.497 (1.332-1.682), P < 0.0001; myocardial infarction, 1.501 (1.254-1.796), P < 0.0001; congestive heart failure, 1.699 (1.435-2.013), P < 0.0001; stroke, 1.152 (0.952-1.394) P = 0.1452; and all-cause death, 1.231 (1.098-1.380), P = 0.0004.

CONCLUSION

These results indicate that estimated glomerular filtration rate calculated with the MDRD formula is more informative than estimated creatinine clearance (Cockcroft-Gault) in the prediction of cardiovascular outcomes.

Does the aldosterone:renin ratio predict the efficacy of spironolactone over bendroflumethiazide in hypertension? A clinical trial protocol for RENALDO (RENin-ALDOsterone) study

Background

High blood pressure is an important determinant of cardiovascular disease risk. Treated hypertensives do not attain a risk level equivalent to normotensives. This may be a consequence of suboptimal blood pressure control to which indiscriminate use of antihypertensive drugs may contribute. Indeed the recent ALLHAT[1]study suggests that thiazides should be given first to virtually all hypertensives. Whether this is correct or whether different antihypertensive therapies should be targeted towards different patients is a major unresolved issue, which we address in this study.

The measurement of the ratio of aldosterone: renin is used to identify hypertensive subjects who may respond well to treatment with the aldosterone antagonist spironolactone. It is not known if subjects with a high ratio have aldosteronism or aldosterone-sensitive hypertension is debated but it is important to know whether spironolactone is superior to other diuretics such as bendroflumethiazide in this setting.

Methods/design

The study is a double-blind, randomised, crossover, controlled trial that will randomise 120 hypertensive subjects to 12 weeks treatment with spironolactone 50 mg once daily and 12 weeks treatment with bendroflumethiazide 2.5 mg once daily. The 2 treatment periods are separated by a 2-week washout period. Randomisation is stratified by aldosterone: renin ratio to include equal numbers of subjects with high and low aldosterone: renin ratios.

Primary Objective – To test the hypothesis that the aldosterone: renin ratio predicts the antihypertensive response to spironolactone, specifically that the effect of spironolactone 50 mg is greater than that of bendroflumethiazide 2.5 mg in hypertensive subjects with high aldosterone: renin ratios.

Secondary Objectives – To determine whether bendroflumethiazide induces adverse metabolic abnormalities, especially in subjects with high aldosterone: renin ratios and if baseline renin measurement predicts the antihypertensive response to spironolactone and/or bendrofluazide

Discussion

The numerous deleterious effects of hypertension dictate the need for a systematic approach for its treatment. In spite of various therapies, resistant hypertension is widely prevalent. Among various factors, primary aldosteronism is an important cause of resistant hypertension and is now more commonly recognised. More significantly, hypertensives with primary aldosteronism are also exposed to various other deleterious effects of excess aldosterone. Hence treating hypertension with specific aldosterone antagonists may be a better approach in this group of patients. It may lead on to better blood pressures with fewer medications.

Influence of a single dose of 20 mg tadalafil, a phosphodiesterase 5 inhibitor, on ambulatory blood pressure in subjects with hypertension

AIMS

To test the non-inferiority of a single dose of tadalafil 20 mg compared with placebo with respect to 26-h mean ambulatory systolic and diastolic blood pressure in treated and untreated hypertensive subjects.

METHODS

A multicentre, randomized, double-blind, placebo-controlled crossover study in 114 subjects with hypertension (36 subjects on no therapy with daytime mean ambulatory blood pressure >/= 140/85 mmHg; 38 subjects on two to four classes of antihypertensive agents with daytime mean ambulatory blood pressure >/=140/85 mmHg and 40 subjects on two to four classes of antihypertensive agents with ambulatory blood pressure < 140/85 mmHg).

RESULTS

Overall tadalafil reduced mean ambulatory blood pressure monitor systolic and diastolic blood pressure by 4.8 mmHg [95% confidence interval (Cl) 3.7, 5.9; P < 0.01] and 2.9 mmHg (95% CI 1.9, 3.6; P < 0.01), respectively, compared with placebo. In hypertensive subjects with uncontrolled blood pressure on two to four classes of antihypertensive agents (n = 36) tadalafil reduced mean ABPM systolic and diastolic blood pressure by 7.5 mmHg (95% CI 5.4, 9.6; P < 0.01) and 4.3 mmHg (95% CI 6.1, 8.9; P < 0.01) compared with placebo.

CONCLUSIONS

In patients with uncontrolled hypertension on multiple agents the addition of tadalafil 20 mg lowered mean 26-h blood pressure.

Outcomes in subgroups of hypertensive patients treated with regimens based on valsartan and amlodipine: An analysis of findings from the VALUE trial

BACKGROUND

In the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial the primary outcome (cardiac morbidity and mortality) did not differ between valsartan and amlodipine-based treatment groups, although systolic blood pressure (SBP) and diastolic blood pressure reductions were significantly more pronounced with amlodipine. Stroke incidence was non-significantly, and myocardial infarction was significantly lower in the amlodipine-based regimen, whereas cardiac failure was non-significantly lower on valsartan.

OBJECTIVES

The study protocol specified additional analyses of the primary endpoint according to: sex; age; race; geographical region; smoking status; type 2 diabetes; total cholesterol; left ventricular hypertrophy; proteinuria; serum creatinine; a history of coronary heart disease; a history of stroke or transient ischemic attack; and a history of peripheral artery disease. Additional subgroups were isolated systolic hypertension and classes of antihypertensive agents used immediately before randomization.

METHODS

The 15,245 hypertensive patients participating in VALUE were divided into subgroups according to baseline characteristics. Treatment by subgroup interaction analyses were carried out by a Cox proportional hazard model. Within each subgroup, treatment effects were assessed by hazard ratios and 95% confidence intervals.

RESULTS

For cardiac mortality and morbidity, the only significant subgroup by treatment interaction was of sex (P = 0.016), with the hazard ratio indicating a relative excess of cardiac events with valsartan treatment in women but not in men, but SBP differences in favour of amlodipine were distinctly greater in women. No other subgroup showed a significant difference in the composite cardiac outcome between valsartan and amlodipine-based treatments. For secondary endpoints, a sex-related significant interaction was found for heart failure (P < 0.0001), with men but not women having a lower incidence of heart failure with valsartan.

CONCLUSION

As in the whole VALUE cohort, in no subgroup of patients were there differences in the incidence of the composite cardiac endpoint with valsartan and amlodipine-based treatments, despite a greater blood pressure decrease in the amlodipine group. The only exception was sex, in which the amlodipine-based regimen was more effective than valsartan in women, but not in men, whereas the valsartan regimen was more effective in preventing cardiac failure in men than in women.

The Valsartan Antihypertensive Long-Term Use Evaluation (VALUE) Trial

In the main Valsartan Antihypertensive Long-Term Use Evaluation (VALUE) report, we investigated outcomes in 15 245 high-risk hypertensive subjects treated with valsartan- or amlodipine-based regimens. In this report, we analyzed outcomes in 7080 patients (46.4%) who, at the end of the initial drug adjustment period (6 months), remained on monotherapy. Baseline characteristics were similar in the valsartan (N=3263) and amlodipine (N=3817) groups. Time on monotherapy was 3.2 years (78% of treatment exposure time). The average in-trial blood pressure was similar in both groups. Event rates in the monotherapy group were 16% to 39% lower than in the main VALUE trial. In the first analysis, we censored patients when they discontinued monotherapy ("censored"); in the second, we counted events regardless of subsequent therapy (intention-to-treat principle). We also assessed the impact of duration of monotherapy on outcomes. No difference was found in primary composite cardiac end points, strokes, myocardial infarctions, and all-cause deaths with both analyses. Heart failure in the valsartan group was lower both in the censored and intention-to-treat analyses (hazard ratios: 0.63, P=0.004 and 0.78, P=0.045, respectively). Longer duration of monotherapy amplified between-group differences in heart failure. New-onset diabetes was lower in the valsartan group with both analyses (odds ratios: 0.78, P=0.012 and 0.82, P=0.034). Thus, despite lower absolute event rates in monotherapy patients, the relative risks of heart failure and new-onset diabetes favored valsartan. Moreover, these findings support the feasibility of comparative prospective trials in lower-risk hypertensive patients.

Effects of valsartan compared to amlodipine on preventing type 2 diabetes in high-risk hypertensive patients: the VALUE trial

CONTEXT

Type 2 diabetes is emerging as a major health problem, which tends to cluster with hypertension in individuals at high risk of cardiovascular disease.

OBJECTIVE

To test for the first time the hypothesis that treatment of hypertensive patients at high cardiovascular risk with the angiotensin-receptor blocker (ARB) valsartan prevents new-onset type 2 diabetes compared with the metabolically neutral calcium-channel antagonist (CCA) amlodipine.

DESIGN

Pre-specified analysis in the VALUE trial. Follow-up averaged 4.2 years. The risk of developing new diabetes was calculated as an odds ratio (OR) with 95% confidence intervals (CI) for different definitions of diabetes.

PATIENTS

A sample of 9995 high-risk, non-diabetic hypertensive patients.

INTERVENTIONS

Valsartan or amlodipine with or without add-on medication [hydrochlorothiazide (HCTZ) and other add-ons, excluding other ARBs, angiotensin-converting enzyme (ACE) inhibitors, CCAs].

MAIN OUTCOME MEASURE

New diabetes defined as an adverse event, new blood-glucose-lowering drugs and/or fasting glucose > 7.0 mmol/l.

RESULTS

New diabetes was reported in 580 (11.5%) patients on valsartan and in 718 (14.5%) patients on amlodipine (OR 0.77, 95% CI 0.69-0.87, P < 0.0001). Using stricter criteria (without adverse event reports) new diabetes was detected in 495 (9.8%) patients on valsartan and in 586 (11.8%) on amlodipine (OR 0.82, 95% CI 0.72-0.93, P = 0.0015).

CONCLUSION

Compared with amlodipine, valsartan reduces the risk of developing diabetes mellitus in high-risk hypertensive patients.

Role of blood pressure and other variables in the differential cardiovascular event rates noted in the Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm (ASCOT-BPLA)

BACKGROUND

Results of the Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm (ASCOT-BPLA) show significantly lower rates of coronary and stroke events in individuals allocated an amlodipine-based combination drug regimen than in those allocated an atenolol-based combination drug regimen (HR 0.86 and 0.77, respectively). Our aim was to assess to what extent these differences were due to significant differences in blood pressures and in other variables noted after randomisation.

METHODS

We used data from ASCOT-BPLA (n=19 257) and compared differences in accumulated mean blood pressure levels at sequential times in the trial with sequential differences in coronary and stroke events. Serial mean matching for differences in systolic blood pressure was used to adjust HRs for differences in these events. We used an updated Cox-regression model to assess the effects of differences in accumulated mean levels of various measures of blood pressure, serum HDL-cholesterol, triglycerides and potassium, fasting blood glucose, heart rate, and bodyweight on differences in event rates.

FINDINGS

We noted no temporal link between size of differences in blood pressure and different event rates. Serial mean matching for differences in systolic blood-pressure attenuated HRs for coronary and stroke events to a similar extent as did adjustments for systolic blood-pressure differences in Cox-regression analyses. HRs for coronary events and stroke adjusted for blood pressure rose from 0.86 (0.77-0.96) to 0.88 (0.79-0.98) and from 0.77 (0.66-0.89) to 0.83 (0.72-0.96), respectively. Multivariate adjustment gave HRs of 0.94 (0.81-1.08) for coronary events (HDL cholesterol being the largest contributor) and 0.87 (0.73-1.05) for stroke events.

INTERPRETATION

Multivariate adjustment accounted for about half of the differences in coronary events and for about 40% of the differences in stroke events between the treatment regimens tested in ASCOT-BPLA, but residual differences were no longer significant. These residual differences could indicate inadequate statistical adjustment, but it remains possible that differential effects of the two treatment regimens on other variables also contributed to the different rates noted, particularly for stroke.

Prevention of cardiovascular events with an antihypertensive regimen of amlodipine adding perindopril as required versus atenolol adding bendroflumethiazide as required, in the Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm (ASCOT-BPLA): a multicentre randomised controlled trial

BACKGROUND

The apparent shortfall in prevention of coronary heart disease (CHD) noted in early hypertension trials has been attributed to disadvantages of the diuretics and beta blockers used. For a given reduction in blood pressure, some suggested that newer agents would confer advantages over diuretics and beta blockers. Our aim, therefore, was to compare the effect on non-fatal myocardial infarction and fatal CHD of combinations of atenolol with a thiazide versus amlodipine with perindopril.

METHODS

We did a multicentre, prospective, randomised controlled trial in 19 257 patients with hypertension who were aged 40-79 years and had at least three other cardiovascular risk factors. Patients were assigned either amlodipine 5-10 mg adding perindopril 4-8 mg as required (amlodipine-based regimen; n=9639) or atenolol 50-100 mg adding bendroflumethiazide 1.25-2.5 mg and potassium as required (atenolol-based regimen; n=9618). Our primary endpoint was non-fatal myocardial infarction (including silent myocardial infarction) and fatal CHD. Analysis was by intention to treat.

FINDINGS

The study was stopped prematurely after 5.5 years' median follow-up and accumulated in total 106 153 patient-years of observation. Though not significant, compared with the atenolol-based regimen, fewer individuals on the amlodipine-based regimen had a primary endpoint (429 vs 474; unadjusted HR 0.90, 95% CI 0.79-1.02, p=0.1052), fatal and non-fatal stroke (327 vs 422; 0.77, 0.66-0.89, p=0.0003), total cardiovascular events and procedures (1362 vs 1602; 0.84, 0.78-0.90, p<0.0001), and all-cause mortality (738 vs 820; 0.89, 0.81-0.99, p=0.025). The incidence of developing diabetes was less on the amlodipine-based regimen (567 vs 799; 0.70, 0.63-0.78, p<0.0001).

INTERPRETATION

The amlodipine-based regimen prevented more major cardiovascular events and induced less diabetes than the atenolol-based regimen. On the basis of previous trial evidence, these effects might not be entirely explained by better control of blood pressure, and this issue is addressed in the accompanying article. Nevertheless, the results have implications with respect to optimum combinations of antihypertensive agents.

Valsartan in the treatment of hypertension

Valsartan is a widely used, efficacious and very well-tolerated antihypertensive agent. By specifically blocking the action of angiotensin II on the angiotensin Type 1 receptor, valsartan reduces unwanted effects of angiotensin II, such as aldosterone, vasopressin and endothelin secretion, vasoconstriction, diuresis, endothelial cell hyperplasia, mitogenesis, induction of growth factors and production of collagen. Valsartan has a simple pharmacokinetic profile and requires no metabolism to become active. The dose-related efficacy of valsartan has been clearly demonstrated and the tolerability profile is similar to placebo. Clinical trials in elderly patients show good efficacy and high responder rates with the same doses as in younger patients. Valsartan is available as 80-, 160- and 320-mg tablets, and also in the same doses in combination with hydrochlorothiazide, 12.5 or 25 mg. Availability varies between countries. Beyond the reduction of blood pressure, valsartan is indicated for use in several countries in patients with heart failure and in patients post myocardial infarction, based on the results of the large-scale Valsartan Heart Failure Trial and VALsartan In Acute myocardial iNfarcTion trials. Valsartan has also been shown, in the Valsartan Antihypertensive Long-term Evaluation trial, to reduce the risk of developing new-onset diabetes in hypertensive patients at high risk of cardiac events.

Statin administration prior to ischaemic stroke onset and survival: exploratory evidence from matched treatment-control study

In addition to their lipid-lowering effects, it has been speculated that statins may also have beneficial effects on cerebral circulation and brain parenchyma during ischaemic stroke and reperfusion. We hypothesized that patients who had taken statins prior to stroke onset may have a better survival rate at 1 month and during the follow-up period. We retrospectively studied consecutive ischaemic stroke patients admitted to an acute stroke unit and at least a month's follow-up. From these, we included those patients who, at admission, had reported the use of a statin prior to the stroke onset in the statin group (n = 205). Each patient in the statin group was matched with two patients who reported no statin use (n = 410). Using logistic regression and Cox proportional hazards models, we adjusted for variables that significantly differed between treatment groups or that independently predicted mortality. After adjusting for those variables, statin use was associated with reduced mortality at 1 month [odds ratio 0.24; 95% confidence interval (CI) 0.09-0.67] and during the follow-up period (hazard ratio 0.57; 95% CI 0.35-0.93). The use of statins prior to stroke onset is associated with improved stroke survival within this cohort study with matched controls.

Reduction in cardiovascular events with atorvastatin in 2,532 patients with type 2 diabetes: Anglo-Scandinavian Cardiac Outcomes Trial--lipid-lowering arm (ASCOT-LLA)

OBJECTIVE

This study aims to establish the benefits of lowering cholesterol in diabetic patients with well-controlled hypertension and average/below-average cholesterol concentrations, but without established coronary disease.

RESEARCH DESIGN AND METHODS

In the lipid-lowering arm of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT-LLA), 10,305 hypertensive patients with no history of coronary heart disease (CHD) but at least three cardiovascular risk factors were randomly assigned to receive 10 mg atorvastatin or placebo. Effects on total cardiovascular outcomes in 2,532 patients who had type 2 diabetes at randomization were compared.

RESULTS

During a median follow-up of 3.3 years, concentrations of total and LDL cholesterol among diabetic participants included in ASCOT-LLA were approximately 1 mmol/l lower in those allocated atorvastatin compared with placebo. There were 116 (9.2%) major cardiovascular events or procedures in the atorvastatin group and 151 (11.9%) events in the placebo group (hazard ratio 0.77, 95% CI 0.61-0.98; P = 0.036). For the individual components of this composite end point, the number of events occurring in the diabetes subgroup was small. Therefore, although fewer coronary events (0.84, 0.55-1.29; P = 0.14) and strokes (0.67, 0.41-1.09; P = 0.66) were observed among the patients allocated atorvastatin, these reductions were not statistically significant.

CONCLUSIONS

Atorvastatin significantly reduced the risk of major cardiovascular events and procedures among diabetic patients with well-controlled hypertension and without a history of CHD or markedly elevated cholesterol concentrations. The proportional reduction in risk was similar to that among participants who did not have diagnosed diabetes. Allocation to atorvastatin prevented approximately 9 diabetic participants from suffering a first major cardiovascular event or procedure for every 1,000 treated for 1 year.

Lowering blood pressure for cardiovascular risk reduction

The association between blood pressure and cardiovascular risk is continuous, with no known lower threshold; epidemiologically, the lower the blood pressure, the better. In reality, the relationship must be J- or U-shaped, as a blood pressure of zero is associated with 100% mortality. However, the level of blood pressure control below which risk increases is well below that achieved in clinical practice, and reducing blood pressure is a cornerstone of strategies to reduce cardiovascular risk. Even relatively small reductions in blood pressure (systolic blood pressure 10-12 mmHg, diastolic blood pressure 5-6 mmHg) substantially reduce cardiovascular risk. Optimal cardiovascular protection is achievable through early and aggressive blood pressure control, but precisely which agents confer the greatest benefits for cardiovascular protection remains widely debated. Angiotensin II receptor blockers (ARBs) appear to be unique in providing additional protection beyond blood pressure control, whereas similar claims for other agents do not withstand close scrutiny. Nearly all patients with hypertension require several antihypertensive treatments to reach their target blood pressure, and it is important to choose treatments that are well tolerated and have complementary modes of action. For this reason, ARBs such as telmisartan emerge as logical choices for combination therapy, particularly when combined with a diuretic, as they fulfil all the essential requirements for combination therapy and are effective in a wide range of different types of patient. Regrettably, a rigorous approach to blood pressure control using multiple agents is still rare in general practice, partly because of a lack of understanding and partly because of 'professional non-compliance'. Prescribing habits must change, and soon, if we are to avoid an upsurge in cardiovascular complications.

Prevention of coronary and stroke events with atorvastatin in hypertensive patients who have average or lower-than-average cholesterol concentrations, in the Anglo-Scandinavian Cardiac Outcomes Trial--Lipid Lowering Arm (ASCOT-LLA): a multicentre randomised controlled trial

BACKGROUND

The lowering of cholesterol concentrations in individuals at high risk of cardiovascular disease improves outcome. No study, however, has assessed benefits of cholesterol lowering in the primary prevention of coronary heart disease (CHD) in hypertensive patients who are not conventionally deemed dyslipidaemic.

METHODS

Of 19 342 hypertensive patients (aged 40-79 years with at least three other cardiovascular risk factors) randomised to one of two antihypertensive regimens in the Anglo-Scandinavian Cardiac Outcomes Trial, 10,305 with nonfasting total cholesterol concentrations 6.5 mmol/L or less were randomly assigned additional atorvastatin 10 mg or placebo. These patients formed the lipid-lowering arm of the study. We planned follow-up for an average of 5 years, the primary endpoint being non-fatal myocardial infarction and fatal CHD. Data were analysed by intention to treat.

FINDINGS

Treatment was stopped after a median follow-up of 3.3 years. By that time, 100 primary events had occurred in the atorvastatin group compared with 154 events in the placebo group (hazard ratio 0.64 [95% CI 0.50-0.83], p = 0.0005). This benefit emerged in the first year of follow-up. There was no significant heterogeneity among prespecified subgroups. Fatal and non-fatal stroke (89 atorvastatin vs 121 placebo, 0.73 [0.56-0.96], p = 0.024), total cardiovascular events (389 vs 486, 0.79 [0.69-0.90], p = 0.0005), and total coronary events (178 vs 247, 0.71 [0.59-0.86], p = 0.0005) were also significantly lowered. There were 185 deaths in the atorvastatin group and 212 in the placebo group (0.87 [0.71-1.06], p = 0.16). Atorvastatin lowered total serum cholesterol by about 1.3 mmol/L compared with placebo at 12 months, and by 1.1 mmol/L after 3 years of follow-up.

INTERPRETATION

The reductions in major cardiovascular events with atorvastatin are large, given the short follow-up time. These findings may have implications for future lipid-lowering guidelines.

Angiotensin-II receptor blockers: benefits beyond blood pressure reduction?

Effective treatment of hypertension is essential to reduce the risk of renal and cardiovascular (CV) morbidity. The risks associated with hypertension are modulated by the presence of other factors. This has prompted the quest for agents that have benefits beyond blood pressure (BP) lowering. The angiotensin II receptor blocker (ARB) class of antihypertensive agents represents an important addition to the therapeutic options for elevated BP. Their ability to control BP is equivalent to existing therapies and there is a considerable and mounting evidence-base for their ability to reduce hypertension-associated target organ damage and comorbidities. Studies show that ARBs have clinical benefits across the spectrum of disease severity. In particular, recent large studies have demonstrated that these benefits extend to patients with conditions predisposing to CV events, such as diabetes, left ventricular hypertrophy and microalbuminuria, and where risk factors coexist. Data from these studies suggest that the CV protective effects of ARBs are at least, in part, independent from the BP lowering action. In addition, ARBs are extremely well tolerated, and strong evidence suggests that compliance with therapy--a key factor in achieving adequate BP control--with ARBs is higher than with other antihypertensive agents. Furthermore, flexible dosing and good tolerability profile mean that, where necessary, ARBs can be combined with other classes of antihypertensive agents to achieve adequate BP control and reduce the risk of hypertension-associated morbidity.

Blood pressure dependent and independent effects of antihypertensive treatment on clinical events in the VALUE Trial

The Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial was designed to test whether, for the same achieved blood pressures, regimens based on valsartan or amlodipine would have differing effects on cardiovascular endpoints in high risk hypertension. But inequalities in blood pressure, favouring amlodipine, throughout the multiyear trial precluded comparison of outcomes. A technique of serial median matching, applied at 6 months when treatment adjustments intended to achieve control of blood pressure were complete, created 5006 valsartan-amlodipine patient pairs matched exactly for systolic blood pressure, age, sex, and the presence or absence of previous coronary disease, stroke, or diabetes. Subsequent combined cardiac events, myocardial infarction, stroke, and mortality were almost identical in the two cohorts, but admission to hospital for heart failure was significantly lower with valsartan. Reaching blood pressure control (systolic <140 mm Hg) by 6 months, independent of drug type, was associated with significant benefits for subsequent major outcomes; the blood pressure response after just 1 month of treatment predicted events and survival.

Outcomes in hypertensive patients at high cardiovascular risk treated with regimens based on valsartan or amlodipine: the VALUE randomised trial

BACKGROUND

The Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial was designed to test the hypothesis that for the same blood-pressure control, valsartan would reduce cardiac morbidity and mortality more than amlodipine in hypertensive patients at high cardiovascular risk.

METHODS

15?245 patients, aged 50 years or older with treated or untreated hypertension and high risk of cardiac events participated in a randomised, double-blind, parallel-group comparison of therapy based on valsartan or amlodipine. Duration of treatment was event-driven and the trial lasted until at least 1450 patients had reached a primary endpoint, defined as a composite of cardiac mortality and morbidity. Patients from 31 countries were followed up for a mean of 4.2 years.

FINDINGS

Blood pressure was reduced by both treatments, but the effects of the amlodipine-based regimen were more pronounced, especially in the early period (blood pressure 4.0/2.1 mm Hg lower in amlodipine than valsartan group after 1 month; 1.5/1.3 mm Hg after 1 year; p<0.001 between groups). The primary composite endpoint occurred in 810 patients in the valsartan group (10.6%, 25.5 per 1000 patient-years) and 789 in the amlodipine group (10.4%, 24.7 per 1000 patient-years; hazard ratio 1.04, 95% CI 0.94-1.15, p=0.49).

INTERPRETATION

The main outcome of cardiac disease did not differ between the treatment groups. Unequal reductions in blood pressure might account for differences between the groups in cause-specific outcomes. The findings emphasise the importance of prompt blood-pressure control in hypertensive patients at high cardiovascular risk.