The prevention of dementia with antihypertensive treatment: new evidence from the Systolic Hypertension in Europe (Syst-Eur) study.

BACKGROUND: After the double-blind, placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial ended in February 1997, randomized patients were offered active study medication for a further period of observation. OBJECTIVE: To refine the estimates of the long-term effects of antihypertensive therapy on the incidence of dementia. METHODS: Eligible patients had no dementia and were at least 60 years old. Their systolic blood pressure at entry was 160 to 219 mm Hg, with diastolic blood pressure below 95 mm Hg. Antihypertensive therapy was started immediately after randomization in the active treatment group, but only after termination of the double-blind trial in the control patients. Treatment consisted of nitrendipine (10-40 mg/d), with the possible addition of enalapril maleate (5-20 mg/d), hydrochlorothiazide (12.5-25 mg/d), or both add-on drugs. RESULTS: Median follow-up increased from 2.0 years in the double-blind trial to 3.9 years overall. The incidence of dementia doubled from 32 to 64 cases, 41 of whom had Alzheimer disease. Throughout follow-up, systolic/diastolic blood pressure was 7.0/3.2 mm Hg higher in the 1417 control patients than in the 1485 subjects randomized to active treatment. At the last examination, the blood pressure difference was still 4.2/2.9 mm Hg; 48.1%, 26.4%, and 11.4% of the control patients were taking nitrendipine, enalapril, and/or hydrochlorothiazide, whereas in the active treatment group these proportions were 70.2%, 35.4%, and 18.4%, respectively. Compared with the controls, long-term antihypertensive therapy reduced the risk of dementia by 55%, from 7.4 to 3.3 cases per 1000 patient-years (43 vs 21 cases, P<.001). After adjustment for sex, age, education, and entry blood pressure, the relative hazard rate associated with the use of nitrendipine was 0.38 (95% confidence interval, 0.23-0.64; P<.001). Treatment of 1000 patients for 5 years can prevent 20 cases of dementia (95% confidence interval, 7-33). CONCLUSION: The extended follow-up of Syst-Eur patients reinforces the evidence that blood pressure-lowering therapy initiated with a long-acting dihydropyridine protects against dementia in older patients with systolic hypertension.

Carotid and femoral intima-media thickness in relation to three candidate genes in a Caucasian population.

BACKGROUND: In a Caucasian population, the prevalence and incidence of hypertension, renal function and large artery stiffness were significantly correlated with polymorphisms in the genes encoding the angiotensin-converting enzyme (ACE I/D), aldosterone synthase (-C344T) and the cytoskeleton protein alpha-adducin (Gly460Trp). OBJECTIVE: This study investigated intima-media thickening, a precursor of atherosclerosis, in relation to these genetic polymorphisms. METHODS: Carotid and femoral intima-media thickness were assessed with a wall-track system in 380 subjects enrolled in a population study. Subjects were genotyped for the presence of the ACE D, aldosterone synthase -344T and alpha-adducin 460Trp alleles. The statistical analysis allowed for confounders, interactions among genes, and the non-independence of the phenotypes within families. RESULTS: The sample included 188 men (49.5%). Mean age was 39.8 years. Intima-media thickness of the carotid and femoral arteries averaged 575 and 719 microm, respectively. Intima-media thickness of the femoral-but not carotid-artery increased with the number of ACE D alleles. The effect of ACE genotype on femoral intima-media thickness was confined to carriers of the 460Trp allele and the -344T allele. Expressed as a percentage of the population mean, the mean differences between II and DD homozygotes averaged 13.4% (95% CI 5.6-21.2%) in all subjects, 21.2% (8.0-34.5%) in carriers of the 460Trp allele, 15.4% (4.1-26.8%) in carriers of the -344T allele, and 25.2% (10.7-39.7%) if the 460Trp and -344T alleles were both present. CONCLUSION: This study shows that a relationship exists between the intima-media thickness of the large muscular femoral artery and the ACE gene. This relationship is only apparent in the presence of either the alpha-adducin 460Trp or the aldosterone synthase -344T allele. These findings may have clinical implications for the assessment of genetic cardiovascular risk.

Effects of immediate versus delayed antihypertensive therapy on outcome in the Systolic Hypertension in Europe Trial.

BACKGROUND: To assess the impact of immediate versus delayed antihypertensive treatment on the outcome of older patients with isolated systolic hypertension, we extended the double-blind placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial by an open-label follow-up study lasting 4 years. METHODS: The Syst-Eur trial included 4695 randomized patients with minimum age of 60 years and an untreated blood pressure of 160-219 mmHg systolic and below 95 mmHg diastolic. The double-blind trial ended after a median follow-up of 2.0 years (range 1-97 months). Of 4409 patients still alive, 3517 received open-label treatment consisting of nitrendipine (10-40 mg daily) with the possible addition of enalapril (5-20 mg daily), hydrochlorothiazide (12.5-25 mg daily), or both add-on drugs. Non-participants (n = 892) were also followed up. RESULTS: Median follow-up increased to 6.1 years. Systolic pressure decreased to below 150 mmHg (target level) in 2628 participants (75.0%). During the 4-year open-label follow-up, stroke and cardiovascular complications occurred at similar frequencies in patients formerly randomized to placebo and those continuing active treatment. These rates were similar to those previously observed in the active-treatment group during the double-blind trial. Considering the total follow-up of 4695 randomized patients, immediate compared with delayed antihypertensive treatment reduced the occurrence of stroke and cardiovascular complications by 28% (P = 0.01) and 15% (P = 0.03), respectively, with a similar tendency for total mortality (13%, P = 0.09). In 492 diabetic patients, the corresponding estimates of long-term benefit (P < 0.02) were 60, 51 and 38%, respectively. CONCLUSIONS: Antihypertensive treatment can achieve blood pressure control in most older patients with isolated systolic hypertension. Immediate compared with delayed treatment prevented 17 strokes or 25 major cardiovascular events per 1000 patients followed up for 6 years. These findings underscore the necessity of early treatment of isolated systolic hypertension.

How well can blood pressure be controlled? Progress report on the Systolic Hypertension in Europe Follow-Up Study (Syst-Eur 2).

BACKGROUND: The randomised, double-blind, placebo-controlled Systolic Hypertension in Europe trial (Syst-Eur 1) proved that blood pressure (BP) lowering therapy starting with nitrendipine reduces the risk of cardiovascular complications in elderly patients with isolated systolic hypertension. In an attempt to confirm the safety of long-term antihypertensive therapy based on a dihydropyridine, the Syst-Eur patients remained in open follow-up after the end of Syst-Eur 1. This paper presents the second progress report of this follow-up study (Syst-Eur 2). It describes BP control and adherence to study medications. METHODS: After the end of Syst-Eur 1 all patients, treated either actively or with placebo, were invited either to continue or to start antihypertensive treatment with the same drugs as previously used in the active treatment arm. In order to reach the target BP (sitting SBP <150 mmHg), the first line agent, nitrendipine, could be associated with enalapril and/or hydrochlorothiazide. RESULTS: Of the 3787 eligible patients, 3516 (93%) entered Syst-Eur 2. At the last available visit, 72% of the patients were taking nitrendipine. SBP/DBP at entry in Syst-Eur 2 averaged 160/83 mmHg in the former placebo group and 151/80 mmHg in the former active-treatment group. At the last follow-up visit SBP/DBP in the patients previously randomised to placebo or active treatment had decreased by 16/5 mmHg and 7/5 mmHg, respectively. The target BP was reached by 74% of the patients. CONCLUSION: Substantial reductions in systolic BP may be achieved in older patients with isolated systolic hypertension with a treatment strategy starting with the dihydropyridine calcium-channel blocker, nitrendipine, with the possible addition of enalapril and/or hydrochlorothiazide.

Morbidity and mortality on combination versus monotherapy: a posthoc analysis of the Systolic Hypertension in Europe trial.

BACKGROUND: The current literature supports the immediate use of combinations of antihypertensive drugs in terms of ease of use and adherence, but the key issue whether combination therapy is more effective than monotherapy in the prevention of cardiovascular complications remains unproven. METHODS: We analysed the double-blind (median follow-up 2.0 years) and open follow-up (6.0 years) phases of the Systolic Hypertension in Europe trial. Patients were 60 years or more with an entry systolic/diastolic blood pressure (BP) of 160-219/less than 95 mmHg. Antihypertensive treatment started immediately after randomization in the active-treatment group, but only after completion of the double-blind trial in control patients. Treatment consisted of nitrendipine (10-40 mg/day) with the possible addition of enalapril (5-20 mg/day). We adjusted our analyses for sex, age, history of cardiovascular complications, baseline systolic BP and previous antihypertensive treatment. RESULTS: During the double-blind trial, adding enalapril to nitrendipine (n = 515), compared with the equivalent combination of placebos (n = 559), decreased systolic BP by a further 9.5 mmHg and reduced all cardiovascular events by 51% (P = 0.0035) and heart failure by 66% (P = 0.032), with similar trends for stroke (-51%; P = 0.066) and cardiac events (-44%; P = 0.075). Over the whole duration of follow-up, combination therapy (n = 871), compared with nitrendipine monotherapy (n = 1552), decreased systolic BP by 3.1 mmHg and reduced total mortality (-32%; P = 0.023), with similar trends for all cardiovascular events (-23%; P = 0.081) and stroke (-42%; P = 0.054). CONCLUSION: Despite the limitations of a posthoc analysis, but congruent with the stronger BP reduction, our results suggest that combination therapy with nitrendipine plus enalapril might improve outcome over and beyond the benefits seen with nitrendipine monotherapy.

'Beyond blood pressure' means multiple risk factor intervention, not pleiotropic antihypertensive drugs.

PURPOSE OF REVIEW: We examined the role of blood pressure-lowering compared with class-specific properties of antihypertensive drugs in cardiovascular prevention. RECENT FINDINGS: We reviewed recently published trials and meta-regression analyses. SUMMARY: From 150,000 to 180,000 randomized patients followed up from 3 to 5 years were required to demonstrate a 10-15% benefit 'beyond blood pressure lowering' of newer antihypertensive drugs, such as calcium channel blockers or angiotensin-converting enzyme inhibitors in the prevention of cause-specific cardiovascular complications. Assuming an absolute risk of new-onset diabetes mellitus on older drugs of approximately 10% over 5 years and a relative benefit on the newer drugs of approximately 30%, about 100 patients would have to be treated for 5 years with the newer agents to avert approximately three iatrogenic cases of diabetes. Whether or not new-onset diabetes is associated with increased risk is uncertain. In most patients, optimization of treatment at acceptable tolerance requires rotation through and combination of several drug classes. Combination of different classes of antihypertensive drugs not only enhances the blood pressure-lowering efficacy, but likely decreases the risk of metabolic adverse effects as well. True benefit beyond blood pressure lowering in hypertensive patients comes from multiple risk factor intervention.

Progress in cardiovascular diseases: cognitive function in essential hypertension.

Essential hypertension has rather recently become recognized as a major factor in the development of the 2 main types of dementia, that is, no longer merely vascular dementia but Alzheimer disease as well. The relationship between high blood pressure (BP) and the dementias is quite a complicated one, given a wide variability in temporal courses. The interval between the respective manifestations of hypertension and cognitive deterioration may vary from a few years to several decades. Moreover, temporal relationships may be obscured because of the observation that BP tends to fall in the face of imminent Alzheimer disease. Although the cause-and-effect sequence of this relationship has not been established, it may suggest that a low BP in this phase of life could be equally harmful as hypertension in the preceding period. Individual monitoring of BP and drug titration in the hypertensive elderly may well become mandatory in the highest age group. The question whether some antihypertensive drug categories might act more effectively in preventing cognitive deterioration than others, irrespective of their antihypertensive potential, remains. A modest meta-analysis on our part seems to suggest that suppression of the renin-angiotensin-aldosterone system (RAAS) would fail to offer such protection, in contrast to certain dihydropyridine (DHP) calcium-channel blockers. Unfortunately, recently published comparative prospective megatrials (Anti-hypertensive and Lipid-lowering Treatment to Prevent Heart Attack Trial and Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm) failed to carry any record on the mental status of the study populations, thereby missing a golden opportunity to resolve the above issue. Consequently, there remains an urgent need for further blinded long-term comparative hypertension trials, including follow-up evaluation of cognitive functions in relation to the course of BP.