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J A Staessen

Publications and source records attributed to J A Staessen.

At least 73 records · Page 4Linked to original sources

Development of diagnostic thresholds for automated self-measurement of blood pressure in adults. First International Consensus Conference on Blood Pressure Self-Measurement.

Blood pressure is usually measured by conventional sphygmomanometry, a procedure fraught with many potential sources of error. Automated techniques of measurement, such as ambulatory monitoring and self-measurement, reduce the limitations of conventional sphygmomanometry. However, the diagnostic thresholds applicable for conventional sphygmomanometry cannot be extrapolated to automated measurements. During the past 10 years criteria for normality have gradually been developed for ambulatory blood pressure monitoring. First, the distributions of the ambulatory blood pressure in normotensive subjects and in untreated hypertensive patients who had initially been classified on the basis of their conventional blood pressure were studied. Second, epidemiological studies were performed to investigate the distribution of the conventional and ambulatory blood pressures in the population at large. Third, authors of several studies have now validated the preliminary thresholds for ambulatory monitoring against left ventricular hypertrophy, other signs of target-organ damage and the incidence of cardiovascular complications. Finally, authors of clinical trials investigated whether it is beneficial to patients and cost-effective to diagnose and treat hypertension on the basis of ambulatory monitoring rather than under the sole guidance of conventional sphygmomanometry. For systolic/diastolic measurements, the upper limits of normotension include 130/80, 135/85 and 120/70 mmHg for the 24 h, daytime and night-time blood pressures, respectively. Whereas for ambulatory monitoring a large body of evidence currently supports the proposed diagnostic thresholds, for the self-recorded blood pressure, to a large extent, this evidence must still be collected. In pursuing this goal, the methods applied for ambulatory monitoring may serve as a template. On the basis of a meta-analysis of summary statistics of published articles and a meta-analysis of data from individual subjects, 135/85 mmHg is likely to be the upper limit of normality for the self-measured blood pressure. Obviously, this threshold is preliminary and must be further validated in prognostic studies. However, the present proposal could guide clinicians who wish to use self-measurement to refine the diagnosis and the management of hypertension based on conventional sphygmomanometry.

Adult↗

Predicting cardiovascular risk using conventional vs ambulatory blood pressure in older patients with systolic hypertension. Systolic Hypertension in Europe Trial Investigators.

CONTEXT: The clinical use of ambulatory blood pressure (BP) monitoring requires further validation in prospective outcome studies. OBJECTIVE: To compare the prognostic significance of conventional and ambulatory BP measurement in older patients with isolated systolic hypertension. DESIGN: Substudy to the double-blind placebo-controlled Systolic Hypertension in Europe (Syst-Eur) Trial, started in October 1988 with follow up to February 1999. The conventional BP at randomization was the mean of 6 readings (2 measurements in the sitting position at 3 visits 1 month apart). The baseline ambulatory BP was recorded with a noninvasive intermittent technique. SETTING: Family practices and outpatient clinics at primary and secondary referral hospitals. PARTICIPANTS: A total of 808 older (aged > or =60 years) patients whose untreated BP level on conventional measurement at baseline was 160 to 219 mm Hg systolic and less than 95 mm Hg diastolic. INTERVENTIONS: For the overall study, patients were randomized to nitrendipine (n = 415; 10-40 mg/d) with the possible addition of enalapril (5-20 mg/d) and/or hydrochlorothiazide (12.5-25.0 mg/d) or to matching placebos (n = 393). MAIN OUTCOME MEASURES: Total and cardiovascular mortality, all cardiovascular end points, fatal and nonfatal stroke, and fatal and nonfatal cardiac end points. RESULTS: After adjusting for sex, age, previous cardiovascular complications, smoking, and residence in western Europe, a 10-mm Hg higher conventional systolic BP at randomization was not associated with a worse prognosis, whereas in the placebo group, a 10-mm Hg higher 24-hour BP was associated with an increased relative hazard rate (HR) of most outcome measures (eg, HR, 1.23 [95% confidence interval [CI], 1.00-1.50] for total mortality and 1.34 [95% CI, 1.03-1.75] for cardiovascular mortality). In the placebo group, the nighttime systolic BP (12 AM-6 AM) more accurately predicted end points than the daytime level. Cardiovascular risk increased with a higher night-to-day ratio of systolic BP independent of the 24-hour BP (10% increase in night-to-day ratio; HR for all cardiovascular end points, 1.41; 95% CI, 1.03-1.94). At randomization, the cardiovascular risk conferred by a conventional systolic BP of 160 mm Hg was similar to that associated with a 24-hour daytime or nighttime systolic BP of 142 mm Hg (95% CI, 128-156 mm Hg), 145 mm Hg (95% CI, 126-164 mm Hg) or 132 mm Hg (95% CI, 120-145 mm Hg), respectively. In the active treatment group, systolic BP at randomization did not significantly predict cardiovascular risk, regardless of the technique of BP measurement. CONCLUSIONS: In untreated older patients with isolated systolic hypertension, ambulatory systolic BP was a significant predictor of cardiovascular risk over and above conventional BP.

Aged↗

Environmental exposure to cadmium, forearm bone density, and risk of fractures: prospective population study. Public Health and Environmental Exposure to Cadmium (PheeCad) Study Group.

BACKGROUND: Chronic low-level exposure to cadmium may promote calcium loss via urinary excretion. We undertook a prospective population study to investigate whether environmental exposure to cadmium lowers bone density and increases risk of fractures. METHODS: We measured urinary cadmium excretion, a biomarker of lifetime exposure, in people from ten districts of Belgium, of which six districts bordered on three zinc smelters. We also measured cadmium in soil and in vegetables from the districts, and collected data on incidence of fractures and height loss. Bone density was measured at the forearm just above the wrist by single photon absorptiometry, and calculated as the mean of six proximal and four distal scans. FINDINGS: Mean cadmium excretion at baseline was 8.7 nmol daily. Across the ten districts, mean cadmium concentration in soil ranged from 0.8 to 14.7 mg/kg, and from 0.1 to 4.0 mg/kg dry weight in vegetables. Median follow-up was 6.6 years. Mean forearm bone density in proximal and distal scans was 0.54 g/cm2 and 0.43 g/cm2 in men, and 0.44 g/cm2 and 0.34 g/cm2 in women. In postmenopausal women, a twofold increase in urinary cadmium correlated with 0.01 g/cm2 decrease in bone density (p<0.02). The relative risks associated with doubled urinary cadmium were 1.73 (95% CI 1.16-2.57; p=0.007) for fractures in women and 1.60 (0.94-2.72, p=0.08) for height loss in men. Cadmium excretion in districts near smelters was 22.8% higher (p=0.001) than in other districts, with fracture rates of 16.0 and 10.3 cases per 1000 person-years, respectively, and a population-attributable risk of 35.0%. INTERPRETATION: Even at a low degree of environmental exposure, cadmium may promote skeletal demineralisation, which may lead to increased bone fragility and raised risk of fractures.

Absorptiometry, Photon↗

Treatment of diabetic patients with hypertension.

This review attempts to highlight the potential of calcium-channel blockers in the prevention of sequelae of diabetes mellitus and hypertension in patients who have both disorders. Evidence-based medicine is driven by the results of randomized, clinical trials. Major contributions were therefore derived from post hoc analyses of the diabetic patients enrolled in placebo-controlled trials, such as Systolic Hypertension in the Elderly Program (SHEP), Systolic Hypertension in Europe (Syst-Eur), and Systolic Hypertension in China (Syst-China), and stepped-care blood-pressure-oriented trials, such as the Hypertension Optimal Treatment (HOT) and United Kingdom Prospective Diabetes Study (UKPDS). Several studies, such as the Fosiniprl; versus Amlodipine Cardiovascular Events Trial (FACET) and Appropriate Blood Pressure Control in Diabetes (ABCD) Trial, have compared the relative merits of angiotensin-converting enzyme and calcium-channel blockers in preserving renal function and metabolic balance in diabetic patients with hypertension, but their publications focused on cardiovascular disorders, which were only secondary end points. On balance, the articles reviewed prove that dihydropyridine calcium-channel blockers score particularly well in the prevention of cardiovascular complications in diabetic patients with hypertension.

Antihypertensive Agents↗

Clinical trials in isolated systolic hypertension.

Isolated systolic hypertension affects 8% to 15% of all people older than 60 years of age. In the elderly, systolic hypertension is the major modifiable cardiovascular risk factor. Three placebo-controlled outcome trials on antihypertensive drug treatment of this disorder have been published. This article briefly reviews the main findings of each of these three trials and presents pooled estimates of the benefit of antihypertensive drug treatment for elderly patients with isolated systolic hypertension. A total of 11, 825 patients were enrolled in the Systolic Hypertension in the Elderly Program (SHEP, n = 4736), the Systolic Hypertension in Europe (Syst-Eur, n = 4695), and the Systolic Hypertension in China (Syst-China, n = 2394) trials. The outcome results of these trials were pooled by calculating the common odds ratio for active versus placebo treatment. The pooled results of the outcome trials in older patients with isolated systolic hypertension prove that antihypertensive drug treatment must be prescribed if, on repeated measurement, systolic blood pressure is 160 mm Hg or higher.

Antihypertensive Agents↗

Systolic Hypertension in Europe (Syst-Eur) trial phase 2: objectives, protocol, and initial progress. Systolic Hypertension in Europe Investigators.

The Systolic Hypertension in Europe (Syst-Eur) trial proved that blood pressure (BP) lowering therapy starting with nitrendipine reduces the risk of cardiovascular complications in older (> or = 60 years) patients with isolated systolic hypertension (systolic BP > or = 160 mm Hg and diastolic BP < 95 mm Hg). After the completion of the Syst-Eur trial on 14 February 1997, 3506 consenting patients (93.0% of those eligible) were enrolled in phase 2 of the Syst-Eur trial. This open follow-up study aims to confirm the safety of long-term antihypertensive therapy based on a dihydropyridine. To lower the sitting systolic BP below 150 mm Hg (target BP), the first-line agent nitrendipine (10-40 mg/day) may be associated with enalapril (5-20 mg/day), hydrochlorothiazide (12.5-25 mg/day), both add-on study drugs, or if required any other antihypertensive agent. On 1 November 1998, 3248 patients were still being followed, 86 patients had proceeded to non-supervised follow-up, and 43 had died. The median follow-up in Syst-Eur 2 was 14.3 months. At the last available visit, systolic/diastolic BP in the patients formerly randomised to placebo (n = 1682) or active treatment (n = 1824), had decreased by 13.2/5.2 mm Hg and by 4.6/1.6 mm Hg, respectively, so that the between-group BP difference was 1.7 mm Hg systolic (95% Ci: 0.8 to 2.6 mm Hg; P < 0.001) and 0.9 mm Hg diastolic (95% Cl: 0.4 to 1.5 mm mm Hg; P < 0.001). At the beginning of Syst-Eur 2, the goal BP was reached by 25.4% and 50.6% of the former placebo and active-treatment groups; at the last visit these proportions were 55.9% and 63.1%, respectively. At that moment, 45.9% of the patients were on monotherapy with nitrendipine, 29.3% took nitrendipine in combination with other study drugs. Until the end of 2001, BP control of the Syst-Eur 2 patients will be further improved. Cardiovascular complications and adverse events, such as cancer or gastro-intestinal bleeding, will be monitored and validated by blinded experts.

Aged↗

Overview of the outcome trials in older patients with isolated systolic hypertension.

AIMS: Isolated systolic hypertension affects over 8 to 15% of all subjects older than 60 years. In the elderly, systolic hypertension is the major modifiable cardiovascular risk factor. Three placebo-controlled outcome trials on antihypertensive drug treatment of this disorder have been published. The aim of this article was to shortly review each of these three trials and to present the pooled estimates of benefit of antihypertensive drug treatment in isolated systolic hypertension in the elderly. METHODS AND RESULTS: The Systolic Hypertension in the Elderly Program (SHEP) in the United States, the Systolic Hypertension in Europe (Syst-Eur) trial and the Systolic Hypertension in China (Syst-China) trial published their main findings in 1991, 1997 and 1998, respectively. The outcome results of these trials were pooled by calculating the common odds ratio for active versus placebo treatment for five major end-points. Zelen's exact test for homogeneity did not reach statistical significance for any of the end-points considered. Thus, the hypothesis of a common underlying treatment effect across the three trials was not rejected. Overall, active treatment compared with placebo, reduced all-cause mortality by 17%, cardiovascular mortality by 25%, all cardiovascular end-points by 32%, total stroke by 37% and myocardial infarction including sudden death by 25%. CONCLUSIONS: The pooled results of the outcome trials in older patients with isolated systolic hypertension prove that antihypertensive drug treatment must be prescribed, if on repeated measurement systolic blood pressure is 160 mm Hg or higher.

Aged↗

Symptoms reported by elderly patients with isolated systolic hypertension: baseline data from the SYST-EUR trial. Systolic Hypertension in Europe.

OBJECTIVES: To determine the symptomatic well-being of elderly persons with isolated systolic hypertension. DESIGN AND SETTING: Well-being determined during the placebo run-in period prior to entry to the Systolic Hypertension in Europe (SYST-EUR) trial. SUBJECTS: 641 People, 60 years or older with an average sitting blood pressure of 173/86 mm Hg. OUTCOME MEASURES: 33 Symptomatic complaints determined by a standard interview. RESULTS: The 437 women complained of 25% of the symptoms and the 204 men 21% (P<0.001). A markedly higher prevalence was observed in women compared with men for: pain in the joints of the hands (35% of women complained of this against 22% of men); 'racing heart' (33% against 17%); dry eyes (16% against 6%); blurring of vision (35% against 23%); cramps in the legs (43% against 31%); and a sore throat (15% against 7%). Nocturia was the most frequent complaint (68% in both sexes). Eight symptoms increased with age and one (rash) tended to decline. With increasing systolic pressure women also reported more headaches, unsteadiness, blurring of vision, irregular heart beat and 'racing heart' but, of these, only headaches increased with diastolic pressure. These observations were made after adjusting for age, blood sugar and body mass index (BMI) and were not observed in men. Higher blood sugars were associated with mouth ulcers, 'racing heart', blurring of vision and cramps in the legs. A higher BMI was associated with six symptoms, and a lower age of leaving education with eight. In men, alcohol consumption was related to 'racing heart', and smoking to wheezing and having a dry cough. CONCLUSIONS: A high level of complaint was associated with female gender, increasing age, blood sugar and BMI and a low age of leaving education.

Aged↗

M235T angiotensinogen gene polymorphism and cardiovascular renal risk.

OBJECTIVE: In this meta-analysis, we attempted to derive pooled estimates for the putative associations between various cardiovascular-renal disorders and the M235T polymorphism of the angiotensinogen gene. METHODS: Case-control studies were combined, using the Mantel and Haenszel approach. Joint P values for continuous variables were calculated by Stouffer's method. Continuous measurements reported in different units were expressed on a percentage scale using the intrastudy mean of the MM genotype as denominator. RESULTS: The computerized database used for this analysis included 69 reports with an overall sample size of 27,906 subjects. Overall, possession of the T allele was associated with an increased risk of hypertension. In comparison with the MM reference group (number of studies, n = 32), the excess risk was 31% (P = 0.001) in TT homozygotes and 11% (P = 0.03) in TM heterozygotes. The sensitivity analysis showed that this association was present only in whites (T allelic frequency, f = 42.2%), but not in blacks (f = 77.0%) or Asians (f = 78.0%). Atherosclerotic complications (n = 12), renal microvascular disorders (n = 13), cardiomyopathy (n = 2) or diabetic retinopathy (n = 3) were not correlated with the M235T polymorphism. Publication bias was observed for hypertension, but not for coronary heart disease, including myocardial infarction, and for microvascular nephropathy. Furthermore, in comparison with the MM control group, the circulating angiotensinogen levels (n = 8) were raised by 11 and 7% (P = 0.01) in TT and TM subjects, respectively. In contrast, plasma levels of the angiotensin I converting enzyme (n = 4) and body mass index (n = 15) were not associated with the T allele. CONCLUSION: The T allele encoding angiotensinogen is not associated with atherosclerotic or microvascular complications, but in Caucasians behaves as a marker for hypertension. This association, which may have been inflated by publication bias, does not necessarily imply causality.

Alleles↗

Influence of demographic, anthropometric and lifestyle characteristics on heart rate and its variability in the population.

OBJECTIVE: The purpose of this investigation was to assess the effects of age, gender, posture and their interactions, and of body mass index and lifestyle factors, on heart rate, its total variance and its variability in the frequency domain in a population-based sample of healthy subjects. METHODS: RR interval and respiration were registered in the supine and in the standing position in 302 men and 312 women, aged 25-89 years; 424 subjects were healthy and had recordings suitable for analysis. Power spectral analysis was performed by use of autoregressive modelling and by fast Fourier transform, and the low-frequency (LF) and high-frequency (HF) components were expressed in both absolute (ms2) and normalized units RESULTS: In the supine position, heart rate was higher in women than in men (P<0.001) and was not affected by age. Total variance and absolute LF and HF power markedly declined with age in each gender (P<0.001). Men had higher absolute LF power than women (P<0.001), whereas HF power was similar by gender; the age-related decline of HF power tended to be steeper in women (P = 0.06). The normalized LF and HF powers also decreased with age (P<0.01), except for the LF component in women; young men had higher LF power and lower HF power than young women, but the gender difference disappeared in the sixth decade of life. The LF: HF ratio was not influenced by age in supine men; the ratio was lower in women at young age, but increased to the level of men at greater age. Heart rate increased on standing, whereas its total variance was reduced; HF power declined, irrespective of the units, normalized LF power and the LF: HF ratio increased, whereas absolute LF power decreased (P<0.001). The postural changes of heart rate and of the frequency components did not differ by gender, but were attenuated with increasing age (P<0.05). Alcohol consumption did not influence heart rate and its variability, whereas independent effects of habitual physical activity, smoking habits and body mass index explained no more than 4% of the variance of some measures of heart rate variability. CONCLUSIONS: Age, gender and/or some lifestyle factors significantly affect heart rate and various components of its variability in the supine position and in response to standing. The results are similar for autoregressive modelling and fast Fourier transform, but may differ according to the units in which the spectral components are expressed.

Adult↗

Task force IV: Clinical use of ambulatory blood pressure monitoring. Participants of the 1999 Consensus Conference on Ambulatory Blood Pressure Monitoring.

OBJECTIVE: To reach a consensus on the clinical use of ambulatory blood pressure monitoring (ABPM). METHODS: A task force on the clinical use of ABPM wrote this overview in preparation for the Seventh International Consensus Conference (23-25 September 1999, Leuven, Belgium). This article was amended to account for opinions aired at the conference and to reflect the common ground reached in the discussions. POINTS OF CONSENSUS: The Riva Rocci/Korotkoff technique, although it is prone to error, is easy and cheap to perform and remains worldwide the standard procedure for measuring blood pressure. ABPM should be performed only with properly validated devices as an accessory to conventional measurement of blood pressure. Ambulatory recording of blood pressure requires considerable investment in equipment and training and its use for screening purposes cannot be recommended. ABPM is most useful for identifying patients with white-coat hypertension (WCH), also known as isolated clinic hypertension, which is arbitrarily defined as a clinic blood pressure of more than 140 mmHg systolic or 90 mmHg diastolic in a patient with daytime ambulatory blood pressure below 135 mmHg systolic and 85 mmHg diastolic. Some experts consider a daytime blood pressure below 130 mmHg systolic and 80 mmHg diastolic optimal. Whether WCH predisposes subjects to sustained hypertension remains debated. However, outcome is better correlated to the ambulatory blood pressure than it is to the conventional blood pressure. Antihypertensive drugs lower the clinic blood pressure in patients with WCH but not the ambulatory blood pressure, and also do not improve prognosis. Nevertheless, WCH should not be left unattended. If no previous cardiovascular complications are present, treatment could be limited to follow-up and hygienic measures, which should also account for risk factors other than hypertension. ABPM is superior to conventional measurement of blood pressure not only for selecting patients for antihypertensive drug treatment but also for assessing the effects both of non-pharmacological and of pharmacological therapy. The ambulatory blood pressure should be reduced by treatment to below the thresholds applied for diagnosing sustained hypertension. ABPM makes the diagnosis and treatment of nocturnal hypertension possible and is especially indicated for patients with borderline hypertension, the elderly, pregnant women, patients with treatment-resistant hypertension and patients with symptoms suggestive of hypotension. In centres with sufficient financial resources, ABPM could become part of the routine assessment of patients with clinic hypertension. For patients with WCH, it should be repeated at annual or 6-monthly intervals. Variation of blood pressure throughout the day can be monitored only by ABPM, but several advantages of the latter technique can also be obtained by self-measurement of blood pressure, a less expensive method that is probably better suited to primary practice and use in developing countries. CONCLUSIONS: ABPM or equivalent methods for tracing the white-coat effect should become part of the routine diagnostic and therapeutic procedures applied to treated and untreated patients with elevated clinic blood pressures. Results of long-term outcome trials should better establish the advantage of further integrating ABPM as an accessory to conventional sphygmomanometry into the routine care of hypertensive patients and should provide more definite information on the long-term cost-effectiveness. Because such trials are not likely to be funded by the pharmaceutical industry, governments and health insurance companies should take responsibility in this regard.

Antihypertensive Agents↗

The international database of self-recorded blood pressures in normotensive and untreated hypertensive subjects.

OBJECTIVES: To pool data from individual subjects in an attempt to determine an operational threshold for making clinical decisions based on the self-recorded blood pressure (SRBP) and to examine how many hypertensive subjects, diagnosed by conventional blood pressure (CBP) measurement, would have a self-recorded blood pressure within the normotensive range if the proposed thresholds were applied. DATA SOURCES: Thirteen research groups studied 4668 untreated subjects. RESULTS: In total 2401 subjects were normotensive, 494 were borderline hypertensive and 1773 were definitely hypertensive. Hypertension had been diagnosed from the mean of 1-6 (median 3) CBP measurements obtained during 1-3 (median 1) visits. The reference values for SRBP measurements determined from the 95th percentiles of the distributions for normotensive subjects were 137 mmHg systolic and 85 mmHg diastolic. Of the subjects with systolic hypertension, 16% had systolic SRBP </= 137 mmHg. Similarly, 25% of those with diastolic hypertension had diastolic SRBP </= 85 mmHg. The probability that hypertensive subjects had SRBP below these thresholds was 34% (diastolic) to 62% (systolic) greater for women than it was for men, was 2-3 times greater if fewer than three CBP measurements had been averaged for establishing the diagnosis of hypertension, and increased by 50% (diastolic) to 126% (systolic) when SRBP had been measured on more than 3 days. In contrast, for each 10 mmHg increment in systolic CBP, this probability decreased by 35% for systolic SRBP and by 11% for diastolic SRBP; for each 5 mmHg increment in diastolic CBP it decreased by 36% for diastolic SRBP. In addition, for systolic blood pressure, the probability decreased by 31% for each 10-year increment in age. CONCLUSIONS: Until the relationship between SRBP and the incidence of cardiovascular morbidity and mortality has been clarified further by prospective studies, a mean self-recorded blood pressure above 137 mmHg systolic or 85 mmHg diastolic may be considered hypertensive. Among the hypertensive patients 16-31% had SRBP below these thresholds, but this proportion decreased if the hypertensive subjects had higher CBP.

Adolescent↗

[Treatment of isolated systolic arterial hypertension and prevention of dementia in aged patients. The Syst-Eur multicenter study].

UNLABELLED: The aim of the vascular dementia project, set up in the framework of the double-blind placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial, was to investigate the influence of antihypertensive drug treatment on the incidence of vascular dementia. The study was run on non-demented patients, at least 60 years old, with isolated systolic hypertension (sitting blood pressure of 160-219 mmHg for systolic and below 95 mmHg for diastolic). Treatment was initiated with nitrendipine (10-40 mg/day) possibly associated with enalapril (5-20 mg/day) and/or hydrochlorothiazide (12.5-25 mg/day). Cognitive function was assessed at baseline and annually by the Mini Mental State Examination (MMSE). The diagnosis of dementia was based on the DSM-III-R criteria. The etiology of dementia was established using the Modified Ischemic Score or the Hachinski score when brain imaging was not available. Median follow-up by intention-to-treat was 2.0 years. The incidence of dementia was reduced by 50% from 7.7 per 1000 patient-years in the placebo group (number of patients 1,180) to 3.7 cases per 1000 p-a in the active treatment group (n = 1,238) (21 vs 11 patients, p = 0.05). At the last available evaluation, systolic and diastolic blood pressure were 8.3 mmHg and 3.8 mm Hg lower (p < or = 0.001) in the active-treatment group, but on average the MMSE scores remained stable in both groups. CONCLUSION: In older people with isolated systolic hypertension, antihypertensive treatment started with nitrendipine may reduce the incidence of dementia. At the rate observed in the placebo group, treating 1,000 patients for 5 years would prevent 19 cases of dementia.

Aged↗

Normality of ambulatory blood pressure.

An operational threshold for making clinical decision on the basis of ambulatory blood pressure monitoring must be defined. This requires that the relationship between the ambulatory pressure and the incidence of cardiovascular complications be clarified beyond present understanding. Preliminary cut-off points for ambulatory monitoring were derived by averaging the 95th percentiles of the ambulatory blood pressure measurements for the normotensive subjects enrolled in various large-scale studies. According to this approach, the upper limits of normotension, calculated by rounding downwards, would be 130/80mmHg for the 24h blood pressure and 135/85 and 120/70mmHg for the daytime and night-time blood pressures. Abnormality, obtained by rounding upwards, would be blood pressure levels exceeding 135/85, 140/90 and 125/75mmHg, respectively.

Blood Pressure↗

Diagnostic thresholds for the clinical use of ambulatory blood pressure monitoring.

The technique of noninvasive ambulatory blood pressure monitoring is now well established as an instrument in clinical research and as a diagnostic tool in clinical practice. Diagnostic thresholds for ambulatory monitoring were derived by averaging the 95th percentiles of the ambulatory blood pressure measurements in the normotensive subjects enrolled in various large-scale studies. Subjects normotensive on conventional sphygmomanometry, in the absence of other risk factors, have a low cardiovascular risk profile in comparison with their hypertensive counterparts. The evidence from prospective outcome studies also supports the proposed thresholds. More outcome studies are still ongoing. However, their results are unlikely to change the proposed thresholds, which are in line with the recommendations of the JNC VI (the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure) and those of many other national expert committees.

Blood Pressure↗