Showing papers on "Ambulatory blood pressure published in 1999"

Predicting cardiovascular risk using conventional vs ambulatory blood pressure in older patients with systolic hypertension.

Abstract: ContextThe clinical use of ambulatory blood pressure (BP) monitoring requires further validation in prospective outcome studies.ObjectiveTo compare the prognostic significance of conventional and ambulatory BP measurement in older patients with isolated systolic hypertension.DesignSubstudy 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.SettingFamily practices and outpatient clinics at primary and secondary referral hospitals.ParticipantsA total of 808 older (aged ≥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.InterventionsFor 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 MeasuresTotal and cardiovascular mortality, all cardiovascular end points, fatal and nonfatal stroke, and fatal and nonfatal cardiac end points.ResultsAfter 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.ConclusionsIn untreated older patients with isolated systolic hypertension, ambulatory systolic BP was a significant predictor of cardiovascular risk over and above conventional BP.

Guidelines for management of hypertension: report of the third working party of the British Hypertension Society.

Abstract: Use non-pharmacological measures in all hypertensive and borderline hypertensive people. Initiate antihypertensive drug therapy in people with sustained systolic blood pressures (BP) >/=160 mm Hg or sustained diastolic BP >/=100 mm Hg. Decide on treatment in people with sustained systolic BP between 140 and 159 mm Hg or sustained diastolic BP between 90 and 99 mm Hg according to the presence or absence of target organ damage, cardiovascular disease or a 10-year coronary heart disease (CHD) risk of >/=15% according to the Joint British Societies CHD risk assessment programme/risk chart. In people with diabetes mellitus, initiate antihypertensive drug therapy if systolic BP is sustained >/=140 mm Hg or diastolic BP is sustained >/=90 mm Hg. In non-diabetic hypertensive people, optimal BP treatment targets are: systolic BP /=15% and in whom blood pressure is controlled to the audit standard. In accordance with existing British recommendations, statin therapy is recommended for hypertensive people with a total cholesterol >/=5 mmol/L and established vascular disease, or 10-year CHD risk >/=30% estimated from the Joint British Societies CHD risk chart. Glycaemic control should also be optimised in diabetic subjects. Specific advice is given on the management of hypertension in specific patient groups, ie, the elderly, ethnic subgroups, diabetes mellitus, chronic renal disease and in women (pregnancy, oral contraceptive use and hormone replacement therapy). Suggestions for the implementation and audit of these guidelines in primary care are provided.

Predicting cardiovascular risk using conventional vs ambulatory blood pressure in older patients with systolic hypertension

Abstract: 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.

Docosahexaenoic Acid but Not Eicosapentaenoic Acid Lowers Ambulatory Blood Pressure and Heart Rate in Humans

Abstract: —Animal studies suggest that the 2 major ω3 fatty acids found in fish, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may have differential effects on blood pressure (BP) and heart rate (HR). The aim of this study was to determine whether there were significant differences in the effects of purified EPA or DHA on ambulatory BP and HR in humans. In a double-blind, placebo-controlled trial of parallel design, 59 overweight, mildly hyperlipidemic men were randomized to 4 g/d of purified EPA, DHA, or olive oil (placebo) capsules and continued their usual diets for 6 weeks. Fifty-six subjects completed the study. Only DHA reduced 24-hour and daytime (awake) ambulatory BP ( P P =0.001). Relative to the placebo group, DHA reduced 24-hour HR by 3.5±0.8 bpm, daytime HR by 3.7±1.2 bpm, and nighttime HR by 2.8±1.2. EPA had no significant effect on ambulatory BP or HR. Supplementation with EPA increased plasma phospholipid EPA from 1.66±0.07% to 9.83±0.06% ( P P

Cardiac and arterial target organ damage in adults with elevated ambulatory and normal office blood pressure.

Abstract: “White coat normotension”—elevated ambulatory blood pressure but normal office blood pressure—is associated with left ventricular mass and carotid wall thickness similar to those in patients with s...

Ambulatory Blood Pressure

Abstract: —Previous studies have reported results on 24-hour ambulatory blood pressure (ABP) in Europe and Japan, but no data exists from South America. In this study, we conducted a population surve...

Microvascular function relates to insulin sensitivity and blood pressure in normal subjects

Abstract: Background—A strong but presently unexplained inverse association between blood pressure and insulin sensitivity has been reported. Microvascular vasodilator capacity may be a common antecedent linking insulin sensitivity to blood pressure. To test this hypothesis, we studied 18 normotensive and glucose-tolerant subjects showing a wide range in insulin sensitivity as assessed with the hyperinsulinemic, euglycemic clamp technique. Methods and Results—Blood pressure was measured by 24-hour ambulatory blood pressure monitoring. Videomicroscopy was used to measure skin capillary density and capillary recruitment after arterial occlusion. Skin blood flow responses after iontophoresis of acetylcholine and sodium nitroprusside were evaluated by laser Doppler flowmetry. Insulin sensitivity correlated with 24-hour systolic blood pressure (24-hour SBP; r=−0.50, P<0.05). Capillary recruitment and acetylcholine-mediated vasodilatation were strongly and positively related to insulin sensitivity (r=0.84, P<0.001; r=0.7...

Effects of Smoking Cessation on Blood Pressure and Heart Rate Variability in Habitual Smokers

Abstract: —We investigated the effects of 1-week of smoking cessation on ambulatory blood pressure, heart rate, and heart rate variability in 39 normotensive male habitual smokers (mean±SEM, 32.5±1.0...

Ambulatory Physical Activity as a Determinant of Diurnal Blood Pressure Variation

Abstract: There are reports that indicate that diurnal blood pressure (BP) variation, in addition to high BP per se, is related to target organ damage and the incidence of cardiovascular events. However, the determinants of diurnal BP variation are not adequately understood. We used actigraphy and ambulatory BP monitoring to study the diurnal variation of BP and physical activity in 160 adults. Within individuals, activity was more strongly related to pulse rate than to BP. The correlation between BP and activity was stronger during sleep than when awake, but the correlation between activity and pulse rate was higher during the awake period than during sleep. Between individuals, the sleep/awake ratio of systolic BP (SBP) was correlated with mean sleep activity (r=.17, P /=20% of awake SBP), 102 dippers (with decreases of >/=10% to <20%), and 39 nondippers (with decreases of <10%), no significant differences existed in awake activity among the groups. However, the nondippers exhibited greater sleep activity than extreme dippers (P<0.05) and an increased sleep/awake activity ratio compared with extreme dippers and dippers (P<0.01). Extreme dipping may also be associated with increased BP variability (P=0.08). Individual SBP responses to activity (the within-person slope of awake SBP regressed on activity) did not differ significantly among the 3 subgroups. In conclusion, physical activity is one of the determinants of ambulatory BP and its diurnal variation. We hypothesize that the association of sleep activity to sleep BP and dipping reflects differences in sleep quality.

Ambulatory assessment : computer-assisted psychological and psychophysiological methods in monitoring and field studies

Abstract: Part 1 introduction: ambulatory assessment - issues and perspectives the naturalistic approach in differential psychology - the consistency issue. Part 2 New methodologies: assessment of experience, activation, and cognitive performance related to the time of the day, setting, and situational consistencies a computer-assisted self-monitoring procedure for assessing stress-related behaviour under real-life conditions computer-assisted interaction diary on social networks, social support and interpersonal stress computer-assisted versus paper & pencil-based self-monitoring - compliance, reactivity, and reliability temporal analysis of speech patterns in the real world using the LOGOPORT interactive monitoring and contingency analysis of emotionally induced ECG changes - methodology and applications field trials oa an interactive ambulatory heart rate monito ambulatory assessment of parasympathetic/sympathetic balance by impedance cardiography concurrent assessment of blood pressure, heart rate, activity, subjective state, and free commentaries on important episodes in everyday life continuous assessment of finger blood pressure and other hemodynamic and behavioral variables in everyday life towards a comprehensive technology for the recording and analysis of multiple physiological parameters within their behavioral and environmental context laboratory-field studies for improvement of ambulatory monitoring methodology strategies and designs in ambulatory assessment. Part 3 Monitoring and assessment in the workplace: psychophysiological analysis of work strain and action-oriented patterns of coping validation studies of emotional, mental and physical strain components in the field psychophysiological analysis of the stress-strain processes under different break schedules during computer work. Part 4 Monitoring and assessment of patients: ambulatory assessment of clinical anxiety psychophysiological monitoring of transient ischemic episodes in patients with coronary heart disease ambulatory blood pressure monitoring - promises and limitations in behavioral medicine ambulatory monitoring of sleep apnea ambulatory assessment of subjective and objective symptoms of diabetic patients signal-contingent computer diary for the assessment of psychological precedents of migraine attacks.

ABPM comparison of the antihypertensive profiles of the selective angiotensin II receptor antagonists telmisartan and losartan in patients with mild-to-moderate hypertension.

Abstract: The antihypertensive efficacy and tolerability profiles of the selective AT1 receptor antagonists telmisartan and losartan were compared with placebo in a 6-week, multinational, multicentre, randomised, double-blind, double-dummy, parallel-group study of 223 patients with mild-to-moderate hypertension, defined as clinic diastolic blood pressure (DBP) >/=95 and /=140 and /=85 mm Hg. After a 4-week single-blind placebo run-in, eligible patients were randomised to receive telmisartan 40 mg, telmisartan 80 mg, losartan 50 mg, or placebo. Ambulatory blood pressure monitoring (ABPM) after 6 weeks of double-blind therapy showed that all active treatments produced significant (P < 0.01) reductions from baseline in 24-h mean SBP and DBP compared with placebo. During the 18-to-24 h period after dosing, the reductions in SBP/DBP with telmisartan 40 mg (10.7/6.8 mm Hg) and 80 mg (12.2/7. 1 mm Hg) were each significantly (P <0.05) greater than those observed for losartan 50 mg (6.0/3.7 mm Hg), and losartan was no better than placebo. Also for the 24-h mean blood pressure, telmisartan 40 mg and 80 mg were significantly (P< 0.05) better than losartan 50 mg. Compared with losartan, telmisartan 80 mg produced significantly (P < 0.05) greater reductions in both SBP and DBP during all monitored periods of the 24-h period, while telmisartan 40 mg produced significantly greater reductions in SBP and DBP in the night-time period (10.01 pm to 5.59 am) (P < 0.05) and in DBP in the morning period (6.00 am to 11.59 am) (P < 0.05). All treatments were comparably well tolerated. Telmisartan 40 mg and 80 mg once daily were effective and well tolerated in the treatment of mild-to-moderate hypertension, producing sustained 24-h blood pressure control which compared favourably with losartan.

Estradiol With or Without Progesterone and Ambulatory Blood Pressure in Postmenopausal Women

Abstract: The purpose of this study was to determine whether transdermal estradiol and intravaginal progesterone given in doses to mimic the premenopausal state would lower blood pressure (BP) in postmenopausal women. Fifteen healthy postmenopausal women were studied in each of 3 conditions: on placebo, after 8 weeks of transdermal estradiol 0.2 mg twice per week, and again 2 weeks after addition of intravaginal progesterone 300 mg/d. Women were studied at each point after 2 days of 100 mmol/d sodium intake. Twenty-four-hour ambulatory BP monitoring was performed, and blood was assayed for estradiol, progesterone, and hormones of the renin-angiotensin-aldosterone system (RAAS). ANOVA with pairwise comparisons was used for analysis. Urinary sodium excretion was similar at each time point. Levels of estrogen and progesterone similar to those in premenopausal women were achieved. On estradiol, nocturnal systolic BP (110+/-3 mm Hg), diastolic BP (63+/-2 mm Hg), and mean BP (77+/-2 mm Hg) fell significantly (P<0.02) compared with placebo systolic BP (116+/-2 mm Hg), diastolic BP (68+/-2 mm Hg), and mean BP (82+/-2 mm Hg). Daytime BP followed the same trend but was significantly lower only for mean BP. There was no activation of the RAAS. The addition of progesterone resulted in no further fall in BP but a significant activation of the RAAS. Thus, contrary to what is often assumed, administration of estradiol with or without progesterone not only did not raise BP but rather substantially lowered BP. This BP-lowering effect may be responsible for the lower incidence of hypertension in premenopausal than in postmenopausal women.

Blood Pressure Monitoring. Task force V: White-coat hypertension.

Abstract: TERMINOLOGY Two terms are in current use to describe patients whose blood pressures are high only in a medical setting (white-coat hypertension and isolated office or clinic hypertension). The term white-coat effect is also commonly used to describe the pressor response to the clinic setting. DEFINITIONS White-coat hypertension is generally defined as a persistently elevated clinic blood pressure in combination with a normal ambulatory blood pressure (ABP). There is disagreement regarding the optimal cutoff point for ABP. The white-coat effect is operationally defined as the difference between the clinic blood pressure and daytime ABP. PREVALENCE OF WHITE-COAT HYPERTENSION: This varies according to the definition of white-coat hypertension and the population studied, but is approximately 20% among mild hypertensives, and increases with age. METABOLIC AND BIOCHEMICAL ASPECTS Authors of some studies have suggested that white-coat hypertension is associated with metabolic abnormalities such as hyperlipidemia that lead to an increase in cardiovascular risk, but most have not found this. TARGET-ORGAN DAMAGE: Several measures of target-organ damage have been compared among normotensives, white-coat hypertensives, and sustained hypertensives; these include left ventricular mass, microalbuminuria, and carotid atherosclerosis. In general, target-organ damage in white-coat hypertension is less than that in sustained hypertension, but in some studies it has been found to be more prevalent than in normotensives. MORBIDITY AND MORTALITY Authors of a relatively small number of prospective studies have concluded that white-coat hypertensives have a lower risk of morbidity than do sustained hypertensives, but a larger number have drawn the more general conclusion that, when there is a discrepancy between the clinic blood pressure and ABP, the prognosis is more closely related to the ABP. MANAGEMENT When white-coat hypertensives are prescribed antihypertensive medication there is usually a decrease in clinic blood pressure, but little or no change in ABP. Thus drug treatment is not necessarily indicated. Another issue is the follow-up of white-coat hypertensives; there is general agreement that blood pressure outside the office should be monitored indefinitely. Some patient may have been wrongly classified as white-coat hypertensives, and others may progress to develop sustained hypertension.

Prediction of Coronary and Cerebrovascular Morbidity and Mortality by Direct Continuous Ambulatory Blood Pressure Monitoring in Essential Hypertension

Abstract: Background —The goal of this study was to assess the prognostic value of ambulatory versus clinic blood pressure measurement and to relate cardiovascular risk to ambulatory systolic and diastolic blood pressure levels. Methods and Results —The study population consisted of 688 patients 51±11 years of age who had undergone pretreatment 24-hour intra-arterial ambulatory blood pressure monitoring on the basis of elevated clinic blood pressure. A total of 157 first events were recorded during a 9.2±4.1-year follow-up period. The predictive value of a regression model containing age, sex, race, body mass index, smoking, diabetes mellitus, fasting cholesterol level, and previous history of cardiovascular disease was significantly improved by the addition of any ambulatory systolic or diastolic blood pressure parameter (whether 24-hour, daytime, or nighttime mean) or pulse pressure, whereas inclusion of baseline clinic blood pressure variables did not enhance the prediction of events. The most predictive models contained the ambulatory systolic blood pressure parameters. In the model containing 24-hour mean ambulatory systolic blood pressure ( P =0.001), age ( P <0.001), male sex ( P <0.001), South Asian origin ( P =0.008), diabetes mellitus ( P =0.05), and previous cardiovascular disease ( P <0.001) were additional independent predictors of events. Whereas 24-hour ambulatory systolic blood pressure was linearly related to the incidence of both coronary and cerebrovascular events, 24-hour ambulatory diastolic blood pressure exhibited a positive linear relationship with cerebrovascular events but a curvilinear relationship with coronary events. Conclusions —Ambulatory blood pressure is superior to clinic measurement for the assessment of cardiovascular risk; there is no reduction in coronary risk at lower levels of ambulatory diastolic blood pressure.

Diagnosis of White Coat Hypertension by Ambulatory Blood Pressure Monitoring

Abstract: White coat hypertension (WCH) is common in referred hypertensive patients. Ambulatory blood pressure monitoring (ABPM) is not free from the white coat syndrome. We examined the use of the elevation of the first and last measurements of ABPM for diagnosis of WCH in a hypertensive population that had been referred to a hospital-based hypertension unit. Data were obtained on 1350 patients for clinic and ABPM parameters. WCH, as diagnosed by conventional clinic blood pressure (BP) measurement, was compared with a variety of alternative methods determined from ABPM. In all cases, mean daytime pressure was /=140 mm Hg systolic or 90 mm Hg diastolic. The definitions tested for this elevation were first hour mean pressure, first reading, maximum reading in first hour, last hour mean pressure, last reading, maximum reading in the last hour and maximum reading in first or last hour. Elevation of the maximum pressure in the first hour or last hour above 140 mm Hg systolic or 90 mm Hg diastolic showed a high level of agreement (kappa=0.91) with classical WCH for diagnosis of the white coat syndrome. Termed ambulatory white coat hypertension, patients with this finding were older than classic white coat patients and had higher daytime (127+/-6/78+/-5 mm Hg versus 121+/-5.5/74+/-6 mm Hg, P<0.005 for systolic and diastolic) and nighttime (114+/-11/67+/-8 mm Hg versus 106+/-9/61+/-6 mm Hg, P<0.005 for systolic and diastolic) pressures. They also had a significantly greater Sokolow-Lyon index (leads V(1)+V(5), 21+/-7 mV versus 18+/-6 mV). Elevation of BP above 140 mm Hg systolic or 90 mm Hg diastolic in the first or last hour of monitoring diagnoses patients with a white coat response in whom there is a higher BP profile than in patients with classic white coat response alone. We suggest, therefore, that this is a better measure of the white coat phenomenon.

Clinical value of ambulatory blood pressure monitoring.

Abstract: UNLABELLED Ambulatory blood pressure monitoring (ABPM) has now become an established clinical tool. It is appropriate to take stock and assess the situation of this technique. UPDATE ON EQUIPMENT: Important improvements in equipment have occurred, with reductions in weight, in awkwardness and in noisiness of the machines, better acceptability and tolerance by the patients, and better reliability. Validation programmes have been proposed and should be referred to. Limitations of the technique persist with intermittent recording in current practice. The reproducibility is limited in the short-term while recording over 24 h is acceptable. DIAGNOSIS AND PROGNOSIS: White-coat effect (WCE) is manifested as a transient elevation in blood pressure during the medical visit The frequency of this phenomenon, the size of the effect, age, sex and level of blood pressure (BP) or the situation of occurrence (general practitioner, specialist or nurse) have been interpreted differently. It does not seem that WCE predicts cardiovascular morbidity or mortality. White-coat hypertension (WCH) is diagnosed on the evidence of abnormal clinical measures of BP and normal ABPM. The latest upper limits of normality by ABPM recommended by the JNCVI are < 135/85 mmHg while patients are awake and < 120/75 mmHg while patients are asleep. If we accept these upper limits of normality in ABPM, WCH does not appear to be a real problem as regards risk factors or end-organ effects. In terms of prognosis, data are limited. Cardiovascular morbidity seems low in WCH but identical to that of hypertensive subjects in these studies. However, further studies are needed to confirm these results. WCH does not appear to benefit from anti-hypertensive treatment. It is obvious that the lower the BP regarded as the limit of normality, the less likely the occurrence of secondary effects of metabolism, or end-organ effects or complications in those classified as hypertensive. 24 HOUR CYCLE: One of the most specific characteristics of ABPM is the possibility of being able to discover modification or alteration of the 24 h cycle of BP. Non-dippers are classically defined as those who show a reduction in BP of less than 10/5 mmHg or 10% between the day (06.00-22.00 h) and the night, or an elevation in BP. In contrast, extreme dippers are those in whom the BP reduction is greater than 20%. CARDIOVASCULAR SYSTEM: The data remain inconclusive with regard to the existence of a consistent relationship between the lack of a nocturnal dip in blood pressure and target organ damage. As regards prognosis, it seems that an inversion of the day-night cycle is of pejorative significance. CEREBROVASCULAR SYSTEM: Almost all studies have shown that non-dippers had a significantly higher frequency of stroke than dippers. In contrast, too great a fall in nocturnal BP may be responsible for more marked cerebral ischaemia. RENAL SYSTEM: Non-dippers have a significantly elevated median urinary excretion of albumin. There is a significant correlation between the systolic BP and nocturnal diastolic BP, and urinary excretion of albumin. Various studies have confirmed the increased frequency of change in the 24 h cycle in hypertensive subjects at the stage of renal failure. DIABETES BP abnormalities should be considered as markers of an elevated risk in diabetic subjects but cannot be considered at present as predictive of the appearance of micro-albuminuria or other abnormalities. ABPM is thus of interest in type I or type II diabetes both in the initial assessment and in the follow-up and adaptation of treatment. PHARMACO-THERAPEUTIC USES: The introduction of ABPM has truly changed the means and possibilities of approach to the study of the effects of anti-hypertensive medications, with new possibilities of analysis such as trough-peak ratio smoothness index, etc.

Genetic Polymorphism of CYP11B2 Gene and Hypertension in Japanese

Abstract: Low-renin hypertension is characterized by a high ratio of aldosterone to plasma renin activity (ALD/PRA), which may suggest inappropriately increased aldosterone biosynthesis. The genes for the enzymes involved in aldosterone synthesis may contribute to low-renin hypertension. We investigated the associations between genetic variations of CYP11B2 (aldosterone synthase) T(-344)C and hypertension in 482 Japanese subjects. Subjects older than 50 years with a blood pressure 160/95 mm Hg were considered hypertensive (n=255 subjects). The frequency of the TC+CC genotypes in the normotensive group was significantly lower than in the hypertensive group. Logistic analysis on 482 subjects revealed that body mass index, gender, and the genotype of CYP11B2 T(-344)C were significantly associated with hypertension. ALD and PRA were assessed in 97 subjects with hypertension, and the TC+CC genotypes were significantly associated with higher ALD/PRA. Sixty-five subjects with hypertension were assessed by 24-hour ambulatory blood pressure monitoring, and the frequency of nondippers (a difference in mean blood pressure of <10% between the daytime [6 AM to 9 PM] and nighttime [9 PM to 6 AM] hours) was significantly higher in subjects with the TC+CC (hetero+homo mutation) genotype than in subjects with the TT (wild-type) genotype. Echocardiographic assessment (n=136) revealed that the ratio of left ventricular end-diastolic dimension to height tended to be higher in subjects with the TC+CC genotype than in subjects with the TT genotype. The present study suggests that the (-344)C allele of the CYP11B2 gene may be a genetic marker for low-renin hypertension in Japanese.

Effect of Dietary Patterns on Ambulatory Blood Pressure: Results From the Dietary Approaches to Stop Hypertension (DASH) Trial

Abstract: —We measured ambulatory blood pressure (ABP) in 354 participants in the Dietary Approaches to Stop Hypertension (DASH) Trial to determine the effect of dietary treatment on ABP (24-hour, da...

Prevalence of hypertension in patients on peritoneal dialysis: results of an Italian multicentre study.

Abstract: dialysis strategies and pharmacological management of hypertension. Background. The tenet that peritoneal dialysis is capable of either normalizing or improving blood pressure Key words: ambulatory blood pressure monitoring; control in uraemic patients is based on outdated or antihypertensive therapy; prevalence of hypertension; monocentric experiences. Therefore, we assessed the peritoneal dialysis; white-coat hypertension prevalence of hypertension and the eYcacy of antihypertensive therapy in a large, multicentric cohort of patients on peritoneal dialysis. Methods. Twenty seven out of the 50 centres belonging Introduction to the Italian Co-operative Peritoneal Dialysis Study Group took part in the study. The main patient Cardio- and cerebrovascular events are the main causes selection criteria were: peritoneal dialysis therapy for of morbidity and mortality of patients on peritoneal at least 3 months and no peritonitis or changes in dialysis [1]. Although high blood pressure (BP) is the dialysis technique for at least 1 month. Clinical blood leading factor causing cardiovascular mortality in the pressure was measured according to WHO/ISH general population, scant attention is paid to arterial guidelines. Ambulatory blood pressure monitoring hypertension in recent peritoneal dialysis studies. This was carried out using a SpaceLabs 90207 recorder. might be due to the general belief that end-stage renal Hypertension was defined according to WHO/ISH disease (ESRD)-related hypertension is easily concriteria and staged according to the criteria of the Joint trolled by peritoneal dialysis. Unfortunately, this asserNational Committee on Detection, Evaluation and tion is at least in part based on outdated reports [2]. Treatment of High Blood Pressure (JNC ), 5th Report. In recent years, ambulatory blood pressure monitoring Ambulatory blood pressure monitoring recordings has been applied in peritoneal dialysis patients. This were used to evaluate white-coat hypertension, blood evaluation technique oVers some advantages over trapressure load and the dipping phenomenon. ditional oYce measurement as it avoids ‘observer bias’, Results. Five hundred and four subjects were evalu- ‘digit preference’ of the operator and the stress reaction ated. Hypertension was prevalent in 88.1% of the of the patient, and provides mean BP levels represpopulation, and 362 out of 444 hypertensive patients enting the average of >90 measurements per day. were on antihypertensive therapy. JNC staging Nonetheless, only a few small studies have been carried revealed that 188 patients had moderate to severe out using ambulatory blood pressure monitoring in hypertension. Blood pressure load was pathological in peritoneal dialysis patients [3]. 77.3% of the patients receiving antihypertensive treat- We were thus prompted to conduct a large multicenment. White-coat hypertension was identified in 9.1% tre study to evaluate the prevalence of hypertension of the hypertensive patients not on antihypertensive and the eYcacy of antihypertensive therapy in peritontherapy, and 53.1% of the patients were non-dippers. eal dialysis patients using traditional clinical sphygmoConclusions. The study demonstrates that hyper- manometric measurements and 24 h ambulatory blood tension is a dramatic, unsolved problem in uraemic pressure monitoring recordings. patients treated with peritoneal dialysis, and casts doubts on the eVectiveness of our current peritoneal Subjects and methods

Effect of family responsibilities and job strain on ambulatory blood pressure among white-collar women.

Abstract: OBJECTIVE This study was conducted to determine whether large family responsibilities and their combination with high job strain were associated with an increase in ambulatory blood pressure (BP) among white-collar women. METHODS A cross-sectional study was conducted in a stratified random sample of 199 white-collar women with or without children who were employed full time in jobs involving high or low strain. These women were selected from a population of 3183 women of all ages, employed in eight organizations in Quebec City, Canada. Subjects wore an ambulatory BP monitor for 24 hours during a working day. Mean BPs were calculated. Different measures of family responsibilities were used, based on the number of children and their ages, and domestic work. Job strain was measured using the Job Content Questionnaire recommended by Karasek. RESULTS Family responsibility measures were significantly related to diurnal BP among women holding a university degree (N=69). Indeed, women having large family responsibilities had increases in systolic and diastolic BPs of 2.7 to 5.7/1.8 to 4.0 mm Hg (p< or =.05). Among women holding a university degree, increases in diurnal systolic and diastolic BPs reached 8.1 to 10.9/5.5 to 7.1 mm Hg (p< or =.01) among women having both large family responsibilities and high job strain. These results were independent of confounders. There was no significant association among women without a university degree (N=130). CONCLUSIONS Large family responsibilities were associated with significant increases in diurnal systolic and diastolic BPs among white-collar women holding a university degree. In these women, the combined exposure of large family responsibilities and high job strain tended to have a greater effect on BP than the exposure to only one of these factors.

Multiple Clinic and Home Blood Pressure Measurements Versus Ambulatory Blood Pressure Monitoring

Abstract: To compare multiple clinic and home blood pressure (BP) measurements and ambulatory BP monitoring in the clinical evaluation of hypertension, we studied 239 middle-aged pharmacologically untreated hypertensive men and women who were referred to the study from the primary healthcare provider. Ambulatory BP monitoring was successfully completed for 233 patients. Clinic BP was measured by a trained nurse with a mercury sphygmomanometer and averaged over 4 duplicate measures. Self-recorded home BP was measured with a semiautomatic oscillometric device twice every morning and twice every evening on 7 consecutive days. Ambulatory BP was recorded with an auscultatory device. Two-dimensionally controlled M-mode echocardiography was successfully performed on 232 patients. Twenty-four-hour urinary albumin was determined by nephelometry. Clinic BP was 144.5+/-12.6/94.5+/-7.4 mm Hg, home BP (the mean of 14 self-recorded measures) was 138.9+/-13.1/92.9+/-8.6 mm Hg, home morning BP (the mean of the first 4 duplicate morning measures) was 137.1+/-13.7/92.4+/-9.2 mm Hg, daytime ambulatory BP was 148.3+/-13. 9/91.9+/-7.8 mm Hg, nighttime ambulatory BP was 125.5+/-16.4/75. 6+/-8.9 mm Hg, and 24-hour ambulatory BP was 141.7+/-14.0/87.2+/-7.6 mm Hg. Pearson correlation coefficients of clinic, home, home morning, and daytime ambulatory BPs to albuminuria and to the characteristics of the left ventricle were nearly equal. In multivariate regression analyses, 36% (P<0.0001) of the cross-sectional variation in left ventricular mass index was attributed to gender and home morning systolic BP in models that originally included age, gender, and clinic, self-measured home morning, and ambulatory daytime, nighttime, and 24-hour systolic and diastolic BPs. We concluded that carefully controlled nonphysician-measured clinic and self-measured home BPs, when averaged over 4 duplicate measurements, are as reliable as ambulatory BP monitoring in the clinical evaluation of untreated hypertension.

G-Protein β3 Subunit C825T Variant and Ambulatory Blood Pressure in Essential Hypertension

Abstract: —Recent studies have identified a novel polymorphism (C825T) of the gene encoding the β3 subunit of heterotrimeric G proteins ( Gβ3 ) associated with enhanced activation of G proteins, which appears to be more common in hypertensive patients. In the present study we examine the relationship between this genetic variant and hypertension in 479 white patients with established essential hypertension recruited from the hypertension clinic of the Universitatsklinikum Benjamin Franklin in Berlin, Germany, and 1000 normotensive gender- and age-matched controls. All patients were screened for the presence of secondary hypertension and were further characterized by ambulatory blood pressure measurements performed in 295 treated and 184 untreated patients. Genotype distribution for the Gβ3 -C825T genotype in patients ( CC =204, CT =224, TT =51) was significantly different from that in controls ( CC =514, CT =412, TT =74; χ 2 =11.5, P Gβ3 -C825T variant and essential hypertension, they do not support the hypothesis that this marker is associated with more severe blood pressure in patients with already established hypertension.

Effect of Alcohol Abstinence on Blood Pressure: Assessment by 24-Hour Ambulatory Blood Pressure Monitoring

Abstract: Several studies have shown that cessation of alcohol drinking reduces blood pressure (BP). However, attempts to reproduce these findings by ambulatory BP monitoring (ABPM) have shown inconsistent results. The aim of the present study was to assess the effect of 1 month of proven abstinence from alcohol on the 24-hour BP profile in heavy alcohol drinkers. Forty-two men who were heavy drinkers (>100 g of pure ethanol per day) were consecutively admitted to a general ward for voluntary alcohol detoxification. On the day of admission, they received a total dose of 2 g/kg of ethanol diluted in orange juice in 5 divided doses, and a 24-hour ABPM was performed. A new 24-hour BP monitoring in the same environmental conditions was performed after 1 month of proven alcohol abstinence while the subjects were receiving the same amount of fluid but without the addition of alcohol. After 1 month of proven alcohol abstinence, BP and heart rate (HR) significantly decreased. The reduction was 7.2 mm Hg for 24-hour systolic BP (SBP) (95% CI, 4.5 to 9.9), 6.6 mm Hg for 24-hour diastolic BP (DBP) (95% CI, 4.2 to 9.0), and 7.9 bpm for HR (95% CI, 5.1 to 10.7). The proportion of alcoholic patients considered hypertensive on the basis of 24-hour BP criteria (daytime SBP >/=135 mm Hg or daytime DBP >/=85 mm Hg) fell from 42% during alcohol drinking to 12% after 1 month of complete abstinence. Abstinence did not modify either the long-term BP variability, assessed by SD of 24-hour BP, or its circadian profile. We conclude that abstinence in heavy alcohol drinkers significantly reduces BP assessed by 24-hour ABPM and that this reduction is clinically relevant. These results show that heavy alcohol consumption has an important effect on BP, and thus cessation of alcohol consumption must be recommended as a priority for hypertensive alcohol drinkers.

Hemodynamic Function at Rest, During Acute Stress, and in the Field Predictors of Cardiac Structure and Function 2 Years Later in Youth

Abstract: Left ventricular hypertrophy is an independent predictor of cardiovascular morbidity and mortality. However, predictors of cardiac structure and function in youth are not completely understood. On 2 occasions (2.3 years apart), we examined 146 youth aged initially 10 to 19 years (mean age, 14.2+/-1.8 years). On the initial visit, hemodynamic function was assessed at rest, during laboratory stress (ie, orthostasis, car-driving simulation, video game, and forehead cold), and in the field (ie, ambulatory blood pressure). Quantitative M-mode echocardiograms were obtained on both visits. On both visits, black compared with white youth had higher resting laboratory systolic blood pressure (P<0.02), greater relative wall thickness (P<0.003), greater left ventricular mass indexed by either body surface area or height(2.7) (P<0.01 for both), and lower midwall fractional shortening ratio (P<0.05). Hierarchical stepwise regression analysis indicated that significant independent predictors of follow-up left ventricular mass/height(2. 7) were the initial evaluation of left ventricular mass/height(2.7), body mass index, gender (males more than females), and supine resting total peripheral resistance (final model R(2)=0.53). Left ventricular mass/body surface area was predicted by initial left ventricular mass/body surface area, weight, gender, mean supine resting total peripheral resistance, and systolic pressure response to car-driving simulation (final model R(2)=0.48). Midwall fractional shortening was predicted by initial midwall fractional shortening, race (white more than black), and lower mean supine total peripheral resistance (final model R(2)=0.13). The clinical significance of these findings and their implications for improved prevention of cardiovascular diseases are yet to be determined.

1999 Canadian recommendations for the management of hypertension. Task Force for the Development of the 1999 Canadian Recommendations for the Management of Hypertension.

Abstract: OBJECTIVE: To provide updated, evidence-based recommendations for health care professionals on the management of hypertension in adults. OPTIONS: For patients with hypertension, there are both lifestyle options and pharmacological therapy options that may control blood pressure. For those patients who are using pharmacological therapy, a range of antihypertensive drugs is available. The choice of a specific antihypertensive drug is dependent upon the severity of the hypertension and the presence of other cardiovascular risk factors and concurrent diseases. OUTCOMES: The health outcomes considered were changes in blood pressure and in morbidity and mortality rates. Because of insufficient evidence, no economic outcomes were considered. EVIDENCE: MEDLINE searches were conducted from the period of the last revision of the Canadian Recommendations for the Management of Hypertension (January 1993 to May 1998). Reference lists were scanned, experts were polled and the personal files of the authors were used to identify other studies. All relevant articles were reviewed, classified according to study design and graded according to levels of evidence. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and premature death caused by untreated hypertension. BENEFITS: Harms and costs: The diagnosis and treatment of hypertension with pharmacological therapy will reduce the blood pressure of patients with sustained hypertension. In certain settings, and for specific drugs, blood pressure lowering has been associated with reduced cardiovascular morbidity and mortality. RECOMMENDATIONS: This document contains detailed recommendations pertaining to all aspects of the diagnosis and pharmacological therapy of hypertensive patients. With respect to diagnosis, the recommendations endorse the greater use of non-office-based measures of blood pressure control (i.e., using home blood pressure and automatic ambulatory blood pressure monitoring equipment) and greater emphasis on the identification of other cardiovascular risk factors, both in the assessment of prognosis in hypertension and in the choice of therapy. On the treatment side, lower targets for blood pressure control are advocated for some subgroups of hypertensive patients, in particular, those with diabetes and renal disease. Implicit in the recommendations for therapy is the principle that for the vast majority of hypertensive patients treated pharmacologically, practitioners should not follow a stepped-care approach. Instead, therapy should be individualized, based on consideration of concurrent diseases, both cardiovascular and noncardiovascular. VALIDATION: All recommendations were graded according to the strength of the evidence and the consensus of all relevant stakeholders. SPONSORS: The Canadian Hypertension Society and the Canadian Coalition for High Blood Pressure Prevention and Control.