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The object of this study was to establish normal values for age of clinical tests of autonomic nervous system activity based on an automatic measuring system. Ninety-seven subjects (50 M/47 F) aged 20 to 85 years (average 45 +/- 13 years) with a normal clinical examination and no medication were included in the study. The blood pressure (BP) and heart rate (HR) were measured continuously with the Finapres system. After a resting period, the BP and HR were measured continuously in 5 different situations: dorsal decubitus position for 7 minutes; on getting up actively in less than 3 seconds and for 9 minutes in the upright positions, during deep breathing at 6c/min and Valsalva manoeuvre during a handgrip test at 30% of maximal voluntary strength for 3 minutes. A specific programme (ISN-CNRS) initiated the calculations of the test and performed direct and crossed spectral analysis in the lying and standing positions. The average BP was 120 +/- 18/66 +/- 11 mmHg and HR was 67 +/- 9 b/min. A negative linear correlation was observed with age with respect to the 3 tests investigating vagal activity: 30/15 ratio, spontaneous variations of respiration and HR, ratio of HR at the end of Valsalva with r = -0.43, r = -0.60, r = -0.34 (p < 0.001). The other two tests: variation of systolic BP 1 min 30 after standing and variation of diastolic BP during the handgrip did not change with age.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: this retrospective study was aimed: at comparing the effects of angiotensin converting enzyme inhibitors (ACEI) and those of calcium antagonists (CA) on the pulse pressure of mild to moderate hypertensive patients; at assessing whether these effects were associated with some modifications of blood pressure variability or not., Methods: the ambulatory blood pressure (ABP) recordings of 236 patients who previously entered clinical trials with a mean run-in placebo period of 2 weeks and a mean active treatment phase of 6 weeks (ACEI, n = 115; CA, n = 121) were reviewed. Baseline ABP has been analysed both as a continuous variable and as a categorical one (high when > 139/87 mmHg, low otherwise). Pulse pressure was calculated by the difference systolic ABP-diastolic ABP, whereas BP variability was estimated by the standard deviation and the variation coefficient of each recording. The results are given as percentage (mean +/- standard deviation). In the patients with high baseline systolic ABP, ACEI and CA did not significantly differ regarding their effects on pulse pressure (-11.1 +/- 17.2 vs -6.3 +/- 14.0, NS). By contrast, in the other patients, pulse pressure was lowered to a significantly greater degree by ACEI than by CA (-5.5 +/- 18.7 vs +1.8 +/- 18.8, p = 0.04). These differences were not related to baseline diastolic ABP. No difference at all was found with regard to BP variability which was altered by none of the drugs. In conclusion, pulse pressure, a reliable indicator of arterial compliance, seemed to be more decreased by ACEI than by CA, the difference being significant only in patients with apparent hypertension.

Ambulatory blood pressure monitoring is being widely used now that relatively simple, reliable and well-tolerated, non-invasive blood pressure measuring devices have become available. The following recommendations are only to help physicians to use this technique in their daily practice: only use homologated devices; ambulatory monitoring should be performed during normal, everyday activities; at least one measurement of blood pressure should be taken every 1/4 hour during the day time (7 h-22 h) and every 1/2 hour during the night (22 h-7 h); the arm must be absolutely still and relaxed during the measurement; the function of the measuring device should be checked when the patient is fitted up and when the device is removed; data processing should provide at least: all values of blood pressure and heart rate, and their times of measurement, the mean values of systolic end diastolic blood pressure and heart rate during the day and during the night, the maximal and minimal systolic and diastolic blood pressure values, a chronogramme of the values. Reasonable indications of ambulatory blood pressure monitoring include: elimination of the "white coat" effect: to confirm the diagnosis of borderline hypertension; to demonstrate inversion of diurnal rhythm in severe hypertension; to demonstrate episodic hyper or hypotension; to confirm certain cases of toxaemia of pregnancy. It is also justified in the evaluation of antihypertension therapy, especially in cases of suspected drug resistance.

Objective: To study the structural modifications of a muscular and medium-size radial artery as regards age, in normal subjects (NT) and HT and DTI., Material and Methods: Transverse study with 39 NT aged 48 +/- 16 years, were compared to 22 HT, aged 50 +/- 11 years, and to 22 DT aged 37 +/- 12 years. An echo-tracking system (NIUS 01, Asulabs, Neuchatel, Switzerland) were used to measure the systolic (Ds) and diastolic diameter (Dd) and derive three indices of compliance and storage capacity: systolo-diastolic variation of cross sectional area VSCA = tau [(Ds2/4)-(Dd2/4)] mm2, operative arterial compliance CA = tau Dd (Ds-Dd)/2 (PAS-PAD) in mm2/mmHg., Results: 1. In NT, Ds and Dd increased significantly with age (p < 0.01), likewise the VSCA, and CA (p < 0.002). 2. In HT and DTI, when age was taken into account, the Ds and Dd were significantly greater than in control but VCSA and CA were higher in HT and lower in DT., Conclusion: Similar to ageing changes in NT, HT lead to increase in medium-size radial artery the diameter and storage capacity, while to decrease in DT. This suggests that opposite cardiovascular load induce opposite modifications in arterial wall structure leading to reduce the wall stress.

The object of this study was to compare the variability of blood pressure measured non-invasively with the Finapres under resting conditions in hypertensive patients with non-hypertensive subjects matched for age, and to evaluate the relationship between resting blood pressure, i.e. without any stimulation, and the sensitivity of the baroreflex evaluated by crossed spectral analysis (SA). Thirty-four hypertensives (WHO criteria) untreated for three weeks, with a mean age of 50 +/- 7 years, were compared with 60 control subjects with a mean age of 50 +/- 9 years. The blood pressure and heart rate were measured continuously in the dorsal decubitus and standing positions. The direct and crossed SA was undertaken by a specific programme using the fast Fourier method. The average blood pressure of controls differed significantly from that of the hypertensive population (118 +/- 15/65 +/- 10 mmHg vs 157 +/- 20/86 +/- 11 mmHg). The mean heart rate of the hypertensives was faster: 76 +/- 11 vs 67 +/- 10 beats/min (p < 0.001). Under basal conditions, there was greater absolute variability in the hypertensive subjects but the relative variability and heart rate were the same as those of the controls. Direct SA provided additional data by showing that this variability was due to LF oscillations. Crossed SA showed a change in the sensitivity of the slope of regulation of the baroreflex in hypertensives, 7.35 vs 8.68 ms/mmHg (p < 0.05). These results show that, under basal conditions, it is possible to demonstrate an increase in the absolute variability in blood pressure in hypertensive patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Unlabelled: We studied in a retrospective study 138 consecutive hypertensive patients, the relationship between atherosclerosis lesions in carotid-artery and the ambulatory blood pressure. Only 93 of the 138 patients were finally included in this study because of the quality of information. They were 50 women and 43 men, aged 57.2 +/- 12.6 years., Methodology: The ambulatory blood pressure was recorded by oscillometric method (Spacelab monitor). The carotid artery were studied by echography and doppler., Results: Carotid lesions in hypertensive patients didn't differ significantly when ambulatory systolic blood pressure increased (147,1 mmHg vs 145.2 in the day, and 135.5 mmHg vs 131.7 in the night; ns); Ambulatory diastolic blood pressure was lower during the day when carotid lesions where present (86.5 mmHg vs 93.2; p < 0.05). Ambulatory diastolic blood pressure decreased also with age; Ambulatory pulsed blood pressure increased when carotid lesions where present (59.3 mmHg vs 52.8 in the day and 58 mmHg vs 51.7 in the night; p < 0.05). Ambulatory pulsed blood pressure increased also with age and body mass index., Conclusion: This results suggest a predictive character of the pulsed pressure measure on the existence of carotid artery lesions in hypertensive patients and that a non invasive study of the carotid artery is opportune when pulsed pressure ambulatory measure is high.

Objective: To compare 24-h ABP in normotensive type 1 diabetic patients with and without microalbuminuria., Research Design and Methods: The study was a retrospective comparison of cases and matched control subjects. The first phase included 35 type 1 diabetic patients, normotensive by OMS criteria. The 23 patients with normoalbuminuria (< 15 micrograms/min) were compared with 12 patients with microalbuminuria (> or = 15 micrograms/min). In the second phase, the 12 microalbuminuric patients were paired by sex- and age-matched with 12 normoalbuminuric patients and 12 nondiabetic healthy control subjects. We measured casual systolic and diastolic BP and HR, 24-h ABP and AHR (recorded with a Spacelabs automatic recorder), and microalbuminuria., Results: No correlation between microalbuminuria and casual BP was observed. Microalbuminuria was correlated significantly with diastolic 24-h APR and nocturnal systolic and diastolic ABP (r = 0.35, 0.38, and 0.33, respectively; P < 0.05) and with AHR during all time periods (24-h, r = 0.46; day, r = 0.39; night, r = 0.39; P < 0.05). Normo- and microalbuminuric patients did not differ in casual BP and HR. However, microalbuminuric patients had a significant increase in systolic 24-h ABP (119.1 +/- 8.2 vs. 113.1 +/- 8.1, P = 0.05), diastolic 24-h ABP (74.9 +/- 7.5 vs. 70.2 +/- 5.7, P = 0.04), nocturnal systolic ABP (112.8 +/- 7.1 vs. 105.8 +/- 7.9, P = 0.01), and AHR during all time periods. The same results were observed when patients were paired by age and sex., Conclusions: Normotensive microalbuminuric type 1 patients, although strictly comparable with normoalbuminuric patients for casual BP and HR, have an increased ABP and HR, especially during the night. This difference might reflect dysautonomia. Ambulatory measurement of BP and HR is more appropriate than casual measurements in hemodynamic studies of incipient diabetic nephropathies and could be proposed as an interesting tool for an early prediction of diabetic nephropathy.

Aim: To study spontaneous variations in radial artery compliance., Methods: Compliance was evaluated non-invasively by an echo-tracking system, and variations in sympathovagal tone were analysed by a spectral analysis of continuous blood pressure recordings using a Fast Fourier algorithm. We studied 23 healthy volunteers, aged 25 +/- 4 years (mean +/- SD), at rest, on two occasions at least one day apart (5 +/- 3 days)., Results: There were no significant differences between the means of the arterial compliance measurements and those of the corresponding spectral analysis. However, the magnitude of change in the low-frequency periods (4-66 mHz) was significantly related (P less than 0.01) to a significant and inverse change in compliance for the same level of blood pressure., Conclusions: While it is possible to use spectral analysis to measure the effect of autonomic nervous regulation on radial artery properties, low-frequency periods cannot be safely ascribed to sympathetic effects alone. Other effects must also be taken into account in measurements of radial artery distensibility.

The sympathetic nervous system seems to be a non hemodynamic factor involved in the development of hypertension and in left ventricular hypertrophy determinism. The aim of this study was to estimate the myocardial norepinephrine content in essential hypertensive patients, using a reliable radio-iodinated marker of norepinephrine: the 123I-meta-iodobenzylguanidine (123I-meta-iodobenzylguanidine). Eight male and female hypertensive patients with left ventricular hypertrophy and average age of 52 +/- 9 years underwent a resting, ambulatory and effort blood pressure measure. Echocardiographic parameters allowed measure of left ventricular mass index (according to Devereux, and we considered left ventricular hypertrophy as left ventricular mass index greater than 120g/m2. Plasma norepinephrine is measured at rest. Cardiac and mediastinal radioactivity is detected 4 h after a 4mCi i.v. injection of 123I-meta-iodobenzylguanidine and meta-iodobenzylguanidine myocardial uptake is definite as the cardiac/mediastinal ratio (N:1.78 +/- 0.19). Meta-iodobenzylguanidine-myocardial uptake average value of hypertensive patients was 1.89 +/- 0.19 (1.63 to 2.25) without statistical difference to control subjects. We found a significative correlation between meta-iodobenzylguanidine myocardial uptake and effort systolic blood pressure variation in one hand, and with heart rate increase with effort in the other hand. There is no correlation between meta-iodobenzylguanidine-myocardial uptake and left ventricular mass index or ambulatory blood pressure. In hypertensive patients with left ventricular hypertrophy, meta-iodobenzylguanidine myocardial uptake is normal or high, in agreement with experimental data in SHRs, model of human essential hypertension. Therefore myocardial scintigraphy with 123I-meta-iodobenzylguanidine can appreciate cardiac norepinephrine content in humans.

In order to assess the efficacy of antihypertensive treatment in the population, a study was undertaken in 5 French cities during the commercial fairs of Grenoble, Marseilles, Nice, Toulouse and Lille. The blood pressure was measured according to the WHO recommendations in volunteers. The study included a total of 7107 subjects of both sexes, with 4064 subjects in the 35-64 year age group. The therapeutic efficacy was evaluated in the 791 hypertensive patients who knew their antihypertensive therapy. Taking < 160/95 mmHg as the criterion of efficacy, 52 to 73% of the hypertensive patients were well controlled. However, if the therapeutic objective of normalisation of the blood pressure (BP < 140/90 mmHg) is taken as the criterion of efficacy, only 23 to 29% of the hypertensive patients were controlled whilst their BP remained significantly higher than that of normotensive controls of the same age. The difference in efficacy of antihypertensive therapy between the cities may be explained by the heterogenicity of the populations whereas the treatment did not differ significantly. After adjustment analysis with respect to sex showed that women were better controlled than men whatever the criterion chosen. The group controlled at BP < 160/95 mmHg only differed from the group < 140/90 with respect to the average BP value which was higher before treatment and decreased less with treatment; though this did not achieve statistical significance. In matters of public health, if the ideal blood pressure is taken as < 140/90 mmHg, this study shows that the objective is only attained in one out of four patients in the population studied.

Objective: examination of an automated exploration of autonomic neuropathy using the Ewing score and evaluation of sympatho-vagal tone., Material: continuous non-invasive collection of blood pressure (BP) data by means of Finapress fingerprobe. The signal was analysed after digitization at 500Hz, sampled and computerised. Values of systolic BP (SBP), diastolic BP (DBP) and heart rate (HR) are analysed by Anapres (Notochord)., Protocol: the pressure monitor is placed on the finger and the reading calibrated to the BP value recorded by auscultatory method on the contralateral arm to give a gap of less than 10 mmHg. BP and HR response to five different manoeuvres are recorded, namely: at rest over 7 minutes, after lying decubitus for 15 minutes; on rising suddenly over 3 seconds, and then over 9 minutes standing still; during 2 respiratory manoeuvres (a) deep breathing over 6 cycles per minute, (b) Valsalva pressure at 40 mmHg sustained over 20 seconds; isometric exercise with sustained handgrip at 30% maximal force sustained over 3 minutes., Analysis: a dedicated computer programme displays in graphic form BP and HR over each manoeuvre and allows the operator to locate the exact cut-off of normality for each test of the Ewing score and also measure the balance of sympatho-vagal tone by Fourier transformation of the interval data of HR or BP peaks., Application: this approach allows evaluation of autonomic function and sympatho-vagal tone by means of 40 minutes of clinical testing and two minutes of automated analysis. This approach seems useful in the assessment of the autonomic nervous system in diabetes.

The high incidence of cardiovascular morbidity and mortality in hypertensive patients with left ventricular hypertrophy shows the great interest in understanding the pathophysiology of this process. Many reports suggest the role of catecholamines in generating left ventricular hypertrophy. The aim of this study is to evaluate the effect of labetalol on myocardial norepinephrine content in hypertensive subjects with left ventricular hypertrophy by using an isotopic norepinephrine marker, the 123I-meta-iodobenzylguanidine (123I-MIBG). Eight male and female hypertensive patients with left ventricular hypertrophy were investigated after a 30 day placebo period. Resting, ambulatory and effort blood pressure was measured. Echocardiographic parameters allowed measure of left ventricular mass index according to Devereux. And we considered left ventricular hypertrophy as left ventricular mass index greater than 120 g/m2. Cardiac and mediastinal radioactivity is detected 4 h after a 4 mCi i.v. injection of 123I-MIBG and MIBG myocardial uptake is definite as the cardiac/mediastinal ratio (N : 1.78 +/- 0.19). All subjects received at the beginning of the study (D0) 2 tablets of labetalol 200 mg, increased to 4 tablets if diastolic blood pressure during follow-up remained above 95 mmHg. Patients again underwent these explorations after 3 months of treatment (D90). Labetalol decreases in considerable manner MIBG myocardial uptake as it has been shown that it decreases tissular norepinephrine content in experimental studies. Therefore, MIBG myocardial uptake seems to be a reliable tool in evaluating drugs effect on cardiac sympathetic nervous system.

Forty-one patients with mild to moderate hypertension were included in a multicentre trial. The objective was to assess the influence of the time at which nitrendipine (Nidrel 20 mg) is taken on its efficacy and tolerance. The drug was administered once daily either in the morning or in the evening during 2 consecutive periods of 28 days. Efficacy was assessed on an ambulatory recording of blood pressure over 24 hours. Globally, nitrendipine results in a statistically significant drop in blood pressure which is not influenced by the time of administration. Treatment response varies greatly according to the initial value of ambulatory diastolic blood pressure. There is a clear antihypertensive effect if ADBP is greater than or equal to 90 mmHg and no hypotensive effect if ADBP is less than 90 mmHg. The incidence of adverse effects did not vary according to the time the drug was taken. Biological tolerance was excellent. Nitrendipine, administered once daily alone appears to be an efficient antihypertensive agent, well tolerated both clinically and biologically. Its efficacy is maintained over a 24-hour period regardless of the time at which the drug is taken.

This study was aimed at determining whether baseline ambulatory blood pressure (BP) levels influence the efficacy of angiotensin-converting enzyme inhibitors and calcium antagonists in the same manner. Accordingly, the ambulatory BP recordings of 236 mild to moderate hypertensive patients who had previously entered a clinical trial and had received either a calcium antagonist (n = 121) or an angiotensin-converting enzyme inhibitor (n = 115) were reviewed. The inclusion criterion was a clinic diastolic BP between 95 and 115 mm Hg at the end of the placebo period. Patients were classified according to the difference between their observed and predicted ambulatory BP (the latter assessed by regressing the observed ambulatory BP on the clinic BP). Reduction in ambulatory systolic and diastolic BP seemed to be greater (p less than 0.0001, p = 0.01) in patients receiving an angiotensin-converting enzyme inhibitor than in those who were given a calcium antagonist. However, analysis of variance showed (1) there was a significant interaction (F = 6.37 p = 0.01) between the pharmacologic class and the baseline systolic ambulatory BP; and (2) the difference in diastolic ambulatory BP reduction between both classes was no longer significant when adjusted for baseline diastolic ambulatory BP. In patients with higher than predicted ambulatory BP levels, angiotensin-converting enzyme inhibitors and calcium antagonists had roughly a similar effect (reduction in systolic BP, 9 +/- 8% vs 7 +/- 6%, p = not significant; reduction in diastolic BP, 11 +/- 8% vs 8 +/- 6%, p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

In order to assess the prevalence of arterial hypertension, diabetes mellitus, and of the association of both diseases, and furthermore, to underline the behaviours and feelings of French physicians in front of these combined diseases, a survey has been undertaken by the SOFRES Medical institute and by Laboratoires Hoechst, which involved 304 physicians in private practice and 67 hospital doctors. After face-to-face interviews, each participant had to fill up a questionnaire dealing with his general feelings and attitudes, and then completed 2 case record forms (5 cases for hospital doctors) from their last patients who presented with hypertension and diabetes mellitus. All these informations have allowed us to describe their behaviours. The 304 physicians have been selected with a regional stratification by a random survey quota method that gave a valid sample from the French medical population: 213 general practitioners (GPs), 67 cardiologists, 24 endocrinologists have been involved in the survey. They have been able to observe 149 hypertensive insulin-dependent diabetic patients and 470 hypertensive non insulin-dependent diabetic patients (respectively 24% and 76%). In addition, 67 hospital doctors (32 cardiologists, 17 diabetologists, 18 nephrologists) have been involved and have filled 255 case record forms (120 insulin-dependent and 135 non insulin-dependent diabetic patients). The association between hypertension and diabetes mellitus is very common: 55% out of the diabetic patients treated by GPs presented with hypertension, 20% out of the hypertensive patients presented with diabetes mellitus. The discovery of hypertension is usually followed by the discovery of non insulin-dependent diabetes mellitus. The opposite feature is observed for the insulin-dependent diabetic patients. The majority of the doctors feels that the cardiovascular prognosis of the association is worse than each single disease. The level of blood pressure that is suitable to start an antihypertensive treatment in hypertensive insulin-dependent and non insulin-dependent diabetic patients is generally lower than for non diabetic hypertensive patients, especially for the diabetologists. Concerning antihypertensive treatments, discrepancies have been observed in between feelings and behaviours of physicians. The class of drug that is thought to be used is obviously different from the one which is really used: angiotensin-converting enzyme inhibitors and calcium antagonists, two rather new classes of drugs are popular while classical classes of antihypertensive agents like diuretics and betablockers are still commonly used. Non pharmacological interventions which are useful for both the treatment of hypertension and diabetes mellitus are not commonly recommended by GPs and specialists.

The recent development of ambulatory blood pressure (ABP) monitoring techniques has improved recording of blood pressure in therapeutic trials and in the clinical setting. The application of ABP differs according to which of these 2 applications is being considered. In therapeutic trials, a placebo control is required. The large quantity of precise data acquired with ABP monitoring allows the study of a limited number of patients; it also allows individual study of patients with a 'white coat' response (i.e. elevated blood pressure in response to examination by the clinician). Analysis of data from ABP monitoring may include the following: comparison of mean blood pressure values over 24 hours, daytime or night-time, or over any other selected time period; 24-hour blood pressure profiles, or analysis hour-by-hour, giving true chronotherapy, and providing data regarding the wearing-off of a drug effect or loss of therapeutic control; analysis of blood pressure at particular times, such as on waking; or specific examination of nonresponders. In individual patients, ABP monitoring should be reserved for specific indications. It can be used before initiation of treatment to confirm the necessity for treatment, especially in the context of hypertension at rest or the 'white coat' effect. With established treatment, ABP monitoring can be used in patients with resistant hypertension, in severe hypertension to examine loss of blood pressure control over time or inversion of the day/night cycle, and in patients with a specific illness, e.g. diabetes, in order to obtain the lowest blood pressure readings possible. Examination of these factors assists clinicians to accurately decide upon the timing and frequency of antihypertensive therapy.

Compliance with antihypertensive therapy is usually monitored by questionnaire, tablet counts, or estimation of drug levels in blood or in urine. The aim of this study was to examine patient compliance by means of an "electronic monitor." After 2 weeks of run-in on placebo, 34 moderately hypertensive patients were included in an open, randomized, crossover trial examining the efficacy and tolerance of nitrendipine, 20 mg as a single daily dose (morning or evening) for 1 month. We analyzed the results in 26 patients. Patients were supplied with tablet boxes equipped with a microprocessor (MENS) that registered the timing and duration of opening of the box over both the placebo and nitrendipine periods. Compliance (%) was calculated as the ratio of the number of days that the pill box was opened to the number of days between visits. The compliance was analyzed for each treatment group, namely placebo and nitrendipine morning and evening, over 1 month. Compliance (mean + SD) was 96.5 +/- 7.4% on placebo and 94.4 +/- 10.7% in the morning and 90.6 +/- 15.4% in the evening. Nitrendipine was taken in the morning at 0700 h +/- 2 h and in the evening at 1859 h +/- 2 h 12 min. The frequency of 24 h +/- 1 h intervals between medication was 83.5% on placebo. This frequency was 72.6% for morning dosage and 71.8% for evening dosage on nitrendipine. There were no differences in compliance between the morning and evening groups when analyzed according to age and sex. There was a negative correlation with time (r = -0.57, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

The blood pressure shows circadian variation in normal subjects with higher diurnal than nocturnal values: the difference between day and night time blood pressure is about 10-20 mmHg for systolic and for diastolic blood pressure. These variations are mainly related to physical and/or psychosensorial stress: the physician is himself a cause of increased blood pressure (the "white coat" effect). The degree of the nocturnal decrease in blood pressure which is maximal 2 and 3 o'clock is related to the quality and depth of sleep. The nocturnal decrease is followed by an increase in blood pressure when the person wakes up (early morning peak). Diagnostic signs: a physiological inversion of the circadian rhythm may be observed in people who sleep during the daytime and work at night. There would seem to be less of a nocturnal fall in black persons in the United States. Some pathological conditions can inverse or at least disturb the ciacadian variation: apart from hypertension, this has been reported in autonomic nervous system disease, in diabetics with autonomic neuropathy in some elderly patients, in Cushing's syndrome, after cardiac transplantation, etc... In hypertensives, the lack of nocturnal decrease of the blood pressure or an inversion in circadian rhythm should be looked for in severe and secondary hypertension such as associated with pheochromocytoma, or in renal dialysis patients. In toxaemia of pregnancy, this abnormality may herald an eclamptic crisis. Prognostic signs: in normotensives (especially in black persons) and hypertensives, inversion of the circadian rhythm is associated with more severe left ventricular hypertrophy and a higher morbidity.

Although there has never been a consensus about the presentation and analysis of the results of ambulatory blood pressure recordings, it is important to define the stages and useful means both for studying individual and groups of recordings (therapeutic trials): individual recordings: edition of results, 24 hour display, quantification of the blood pressure over predefined periods, comparison with reference values; therapeutic trials: verification of the quality of the recordings (consecutive hours without measurements, artefacts), preparation of the results for analysis (grouped in hourly mean values), search for confusing factors and non-adherence to the protocol, analysis of efficacy over 24 hours and predefined periods, partial studies (non-responders, normalisation of blood pressure with respect to reference values, control of efficacy over more than 24 hours...). All these stages must be predefined in the study protocol.

Unlabelled: This study evaluates ambulatory blood pressure ABP measurement as a technique for measuring the cardiovascular load in maintenance mechanics working on mechanical lifts at altitudes of over 2,500 meters (stress due to altitude and intensive static and dynamic work)., Method: 25 normotensive workers were studied during real working conditions. Each subject underwent a maximal stress test, and echocardiography. An ABP recording (Spacelab 90207) with BP measurement every 15 minutes and continuous heart rate (HR) monitoring (Essilor IFC85), during 24 hours were performed on the same day., Analysis: study of BP levels and their factors of variation, comparison of this data with continuous HR measurements, and with results of the stress test and echocardiography., Results: even in difficult conditions (while balancing on cables and cable towers), ABP measurements is possible (less than 10% missing values). Systolic (SBP) and diastolic (DBP) blood pressure and HR values adjusted for age are significantly higher during work activity (9:00-12:00, 14:00-15:00) in these subjects than in reference normotensive subjects. ABP did not differ significantly between different types of work while the equivalent mechanical load (work load that gives a stress test HR equal to the mean HR during work) reveals a different between work activities. At night SBP remains higher and HR values lower than in control subjects. In comparison with reference criteria, 3 subjects were considered as having an abnormally high ABP during the daytime. ABP results were not linked with number of years in the profession nor with the altitude at which the subject worked or lived. Although 40% of subjects have a left ventricular mass index greater than 135 g:m2, there is no link between ultrasound and ABP parameters., Conclusion: while ABP measurement seems possible in this type of professional activity, BP values do not appear to be correlated to work level measured. The absence of correlation with left ventricular mass, suggests that the process of cardiovascular adaptation is different from that in even moderately hypertensive subjects.

A number of studies have shown changes and even an inversion of the diurnal cycle in certain affections: Cushing's syndrome, pheochromocytoma, severe renal failure, autonomous nervous system disorders, pre eclampsia etc.... The authors studied diurnal and nocturnal variations of blood pressure in type I diabetics. Twenty-nine normotensive (WHO criteria) type I diabetics (NTD) average age 34.9 +/- 11 years, with diabetes of 13.6 +/- 8 years standing, and 118 normotensive non-diabetics (NT) aged 20 to 60 years (distributed by decennies according to age and sex) were studied. The systolic (SBP) and diastolic blood pressures (DBP) were recorded at rest in the decubitus position by the phase V indirect auscultatory method and during ambulatory monitoring (automatic Spacelabs no. degrees 90207 device) every 15 minutes during the daytime and 20 minutes during the night. The mean values were studied; the values of the heart rates were identical in the NTD and NT populations. Significant difference in SBP between the Nt and NTD were recorded: during daytime there was no difference either in SBP or DPB; during the night, there was a significant difference in SBP. A study of the day-night differences both in absolute and in relative values (day-night difference with respect to daytime values as a percentage) did not show any statistically significant differences between the two populations. Abnormalities of the 24 hour profile, defined as absence of a 5 mmHg fall in nocturnal BP values, were looked for but there were no differences between the NT and NTD subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Circadian blood pressure variations were studied in 110 normotensive (blood pressure less than or equal to 140/90 mmHg) and 142 untreated essential hypertensive (blood pressure greater than or equal to 160/95 mmHg) subjects. Measurements were carried out under full ambulatory conditions by the oscillometric method, using an automatic device (SpaceLabs 5200). Readings taken between 9.00 a.m. and 7.00 p.m. were defined as daytime values (activity), and those taken between 11.00 p.m. and 7.00 a.m. as night-time values (sleep). Blood pressure was significantly higher during the day than at night. The day-night differences were significantly higher in the hypertensive than in the normotensive subjects. There was a significant correlation for both systolic blood pressure (SBP) and diastolic blood pressure (DBP) between the day-night differences and DBP values at rest. The difference between the normotensives and hypertensives was smaller when the day-night difference was calculated as a percentage of the daytime blood pressure, but the SBP difference remained significantly higher in the hypertensives. The number of subjects without a nocturnal blood pressure decrease or with a decrease of less than 5-10 mmHg was not statistically different between the normotensives and the hypertensives. These results are a contribution towards an understanding of day-night blood pressure differences in hypertensive and in normotensive subjects. A knowledge of the 24-h blood pressure profile in the individual patient is important because abnormal profiles may be linked with various etiologies responsible for dysregulation, and might have prognostic implications.

Unlabelled: The study was aimed to search in which site the pulse wave velocity (PWV), is the most reproducible at rest, and determine the best site for measurement. The 3 sites habitually employed carotid-femoral (CF), femoral-dorsalis pedis (FP), subclavian-radial (SCR) were studied twice running at 24 hours interval (D1/D2) at rest after 10 minutes in dorsal decubitus, in 20 borderline hypertensive subjects (mean age 50 +/- 14), treated (n = 7) or non-treated (n = 13). Pulse transit time (dt) was measured with a continuous doppler velocimeter according to the ECG, the PWV calculated from the artery length on each site (dl) according to the formula PWV = dl/dt (m/s)., Statistical Analysis: Wilcoxon test for paired series and correlation coefficients. Whatever the site, no significant difference between measurements 24 hours apart. For each measurement, the variability and standard errors at each site appear greater for CF and FP (24%), than for SCR (14%). Study of the correlations between measurements at each site: the measurements SCR and CF are correlated (r = 0.43, p less than 0.05); those at the other sites are independent of each other., Conclusion: at rest and 24 hrs apart in the hypertensive subject, the PWV is reproducible in the three measurement sites. The CF and FP sites give less consistent results. The SCR site seems to be the most practical: it is the site of BP measurement, it is correlated with the CF site, and its variability and standard error are low.

Comparative study is performed between echocardiographic measurements (TM), exercise test blood pressure profile (ETP) and ambulatory blood pressure load (BPL) in 26 borderline hypertensive subjects (19 males, 7 females). An abnormal ETP is found for 15 subjects (57 p. 100), an abnormal BPL for 10 subjects (38 p. 100). The diastolic interventricular septum thickness (IVS) and the diastolic posterior wall thickness (PWT) are abnormal (greater than 11 mm) for 6 and 3 subjects. Patient with pathologic ETP or/and BPL have greater IVS and PWT than other subjects (p less than 0,001). A good correlation is found between individual activity systolic blood pressure or 24 hours systolic blood pressure means values and PWT, IVS or left ventricular mass. These 3 examinations lead to a better assessment of cardiovascular strain and allow a better diagnosis and therapeutic approach in borderline hypertensive patients.

Study of the blood pressure and cardiac rate changes in the course of an exercise test makes it possible to assess the possibilities of cardiovascular adaptation. This "induced arterial hyperrtensive subjects from those who possibly are not, and to assess correctly the blood pressure changes observed in various circumstances. On effort, an approach of the severity of the haemodynamic disturbance of the consequences of this disturbance, of the efficiency of treatment.

Three french specialist centers have included 19 hypertensive patients in an open cooperative study of the effect of labetalol (L = 200 to 400 mg b.i.d.) on the 24 hour blood pressure (24 h - B.P.) recording by a non invasive method (Spacelabs - Squibb Medical Systems), with a particular assessment of the early morning rise of BP. Each patient was subjected to 2 assessments at the end of a 14 days' placebo period and of a 28 days' treatment period. At the end of the study, the systolic (SBP) and diastolic (DBP). B.P. were significantly decreased at rest (p less than 0.001) and on the 24 hours recording (p less than 0.001). The reduction of B.P. was also significant on day period from 7 a.m. to 22 p.m. (p less than 0.001) and night period from 22 a.m. to 7 a.m. (p less than 0.05) as well as on the early morning period, 3 hours before and after waking (p less than 0.001). The heart rate was significantly reduced during the day (p less than 0.05) and was not on the night. The slope of the early morning rise of B.P. was marked after placebo and significantly decreased after labetalol with a reduction of 52% for SBP and 49% for DBP (p less than 0.001). These results show that labetalol has an antihypertensive effect over 24 hours with a marked effect on the early morning rise of B.P.

The authors report the data of a systematic electrocardiographic study of 307 subjects suffering from hypertension. They analyse the EKG anomalies at rest and after exercise and study the relationships likely to exist between these anomalies and other parameters such as age, blood pressure, etc. They stress the diagnostic but also discriminatory value of this type of investigation in hypertension.

Stress tests have been performed for a long time in patients with coronary disease. The study of blood pressure variations, under these circumstances, is also interesting in hypertension. Several types of stress tests, dynamic and static, may be performed. Dynamic tests on ergometric bicycles are the most frequently performed. The evolution of the BP during stress increases regularly and there is a linear correlation between the BP values and the level of work as well as the heart rate (HR). It is therefore possible to individualize a reference blood pressure profile, according to age and sex. The stress may find applications from a diagnostic, prognostic and therapeutic standpoint. First of all, in borderline HT, the stress test enables to confirm the HT and better differentiate between hyperemotional and hyperkinetic patients. In severe hypertension, the stress test permits to better define the magnitude of the haemodynamic disorder. In true hypertensive patients, undergoing major physical stress (work, sports...) the stress test permits to evaluate the tolerance to stress and the faculties of myocardial adaptation. From a prognostic standpoint, the incidence of permanent hypertension is 2 to 3 times higher in patients presenting an abnormal blood pressure profile. There is a significant correlation between the BP at maximum stress and the left ventricular mass index at all stages of the HT. The stress test makes it possible to better define the mode of action of antihypertensive medications, prescribe a personalized treatment according to these patients reactivity to stress and guarantee the correction of blood pressure abnormalities, since normalisation at rest does not necessarily imply a normalisation during stress.

Cobalt urinary excretion should be a good way to know the level of exposition of subjects submitted to hard metals. The study is done on 28 workers of 3 different workrooms. Sunday 24 hours diuresis is retained. For 5 workers, the urinary cobalt measurements are done from samples made at the beginning and the end of work during 5 days. Atmospheric dust measurements are realized in different points of the 3 workrooms (individual and general samples). For measures atomic absorption spectrometry is used. The results show a good correlation between cobalt exposure and urinary concentrations. Friday evening urinary cobalt is a good expression of week exposure. The results obtained well correlate with those of others authors. Cobalt urinary measures are proposed for supervision of workers exposed to hard metals.

The reproducibility and reliability of measurements performed with an automatic blood pressure measuring device based on the oscillometric method were assessed by comparison with the results obtained by the indirect auscultation using a mercury manometer. The results of the mean values, of the correlation between successive values and of the variation of the values of systolic and diastolic blood pressure show that the readings obtained by the automatic method are very reproducible.

Ambulatory blood pressure monitoring by an automatic non-invasive procedure allows the measurement of a large number of blood pressures and provides information in the variations of blood pressure during normal activity. The development of a programme on a minicomputer has helped simplify the expression of the results by: --a graphical representation of the evaluation of the blood pressure with respect to time (chronogramme); --a histogramme showing the distribution of the blood pressure values; --a representation of the pressure load with respect to time. By stocking the individual results a statistical study could be undertaken of the whole population. Eighteen normotensives, 15 borderline hypertensives and 12 permanent hypertensives were monitored for 24 hours. A circadien variation of blood pressure was observed in all three groups. Over an arbitrary chosen period (9 am-9 pm) the mean blood pressures and heart rates were: --Normotensives: SBP = 134 +/- 19; DBP = 79 +/- 11; HR = 79 +/- 14; --Borderline hypertensives: SBP = 151 +/- 30; DBP = 90 +/- 16; HR = 86 +/- 18; --Permanent hypertensives: SBP = 157 +/- 27; DBP = 102 +/- 17; HR = 83 +/- 17. An interpretation of these results requires information about the normality of the blood pressure levels during normal activities which remains to be studied. Resting values measured in the doctor's surgery need to be compared to ambulatory values in these three groups in order to judge the real significance of this method of measurement, and, in particular, to determine if the resting values are predictive of the blood pressure levels during activity.

The physiological variations of blood pressure and heart rate were studied in the first five minutes of orthostatism in conditions identical to those encountered in clinical medicine. An increase in heart rate and diastolic blood pressure was observed from the first minute. The value of systolic blood pressure decreased as the subject got up and then rose to the value measured when lying down. At the fourth and fifth minute the three parameters were stable at significantly higher values than observed when lying down for the heart rate and diastolic blood pressure, but at an identical level for the systolic blood pressure. This study shows the necessity of measuring the orthostatic blood pressure using a precise technique which detects postural abnormalities when measured in the minute of orthostatism and which gives an assessment of the standing blood pressure when measured at the fifth minute.

In a cross-sectional, and one year retrospective study low back pain risk was analysed in a sample of 1812 subjects stratified by five professions: nurses, industrial workers, truck drivers, construction workers and white collar workers. Data were collected by occupational physicians during annual systematic examinations. Relative risks were significantly higher in nurses and industrial worker occupations than in the control group of white collar employees. Multivariate analysis points out that heavy or light handling, bad postures, non-sitting jobs and exposure to vibration or inclemency are the prevalent occupational factors of low back pain. Housekeeping among females and gardening or odd jobs in males are less but significant extra-professional factors. Prevention should include instruction in lifting techniques and improvement in work conditions.

Starting from projective situations--thematic apperception test (TAT) we have researched personality characteristics liable to be found in hypertensive subjects. With reference to a control group of 59 subjects we have studied 41 essential hypertensive subjects. They undergo a preliminary interview structured on the questionnaire type, are classically tested with the TAT, have one or several free interviews. These data are exploited on three levels and contents = manifest, latent, adaptive. It emerges that there are permanent biographical elements (elements of reactivation. Difficulty to put up with aggressiveness, object loss anxiety, use of operative thought back of adaptation = absence of solution to conflicts and possibilities of passage ?), personality patterns in between obsessional pole neurosis and limit state (Bergeret's nosography). These data partly overlap other research, they encompass a wider field than hypertension, given the structures involved (limit state, psychosomatic component). The lack of mentalization justifies the use of therapeutic techniques such as relaxation, biofeedback...

Variations in blood pressure were investigated by an automatic, non-invasive ambulatory method in 9 subjects with essential hypertension. Recordings were made after 6 week periods during which captopril was taken either once or twice daily, in a double-blind cross-over study. Although the effects of captopril administration either once or twice daily were broadly similar, there was a significant decrease in diastolic blood pressure values on the once-daily regimen. These results suggests that treatment once a day can advantageously replace twice-daily treatment.

Eccrine sweat secretion is studied during physical stress after the administration of a B-blocking agent: Butofilolol. 20 voluntary normotensive subjects, age 24 + 2 ans are submitted to 2 exercises stress test (ergometric bicycle) performed at on week interval. Butofilolol is administrated at a posology of 200 mg, 24 hours and 2 hours, before the test as well as placebo (double blind). Local sweat output is measured 1 min after stress and in the interscapulary region with an evaporimeter. Sweat weight, sweat electrolyte concentrations (sodium, chloride) are analysed from filters papers placed on the forehead. With butofilolol, significative increases of sweet output (+13%), sweat weight (+20%), and sodium (+20%), chloride (+26%) elimination are observed. The subjective observation of the effects of B-blocking agents is confirmed. The way of action of Butofilolol discussed.

23 normotensive subjects in good health are submitted to a "test de l'exposé" and 17 others are submitted to a test on an ergometric bicycle and a hand grip stress test. These tests are performed twice at one week interval, with or without treatment with acebutolol, in double blind. HR,SBP and DBP are measured simultaneously before, during and after each test. Every stress is responsible for a marked increase in the parameters according to different modalities. With ACEBUTOLOL treatment, during the test described and during dynamic stress on ergometric bicycle, HR and SBP are always less elevated. The decreases are dependent either on the stress level or on the reactivity of the subjects. DBP is however basely modified. Under static stress, there is a decrease in HR, in SBP, but also in DBP; actually increase in this parameter is important during this type of stress.

The authors report their findings from a study of the reproductibility of measurements of blood pressure and heart rate both at rest and during exercise (work on a bicycle ergometer) in 19 patients who were tested on two occasions with a mean interval of 9.8 days. A study of the correlations, of variability, and of the findings on applying Student's "t" test, have led us to the conclusion that these parameters are more reproduceable on exercise than at rest, and become increasingly reproduceable as exercise increases. These conclusions support the use of an induced hypertension test under exercise.