Ambulatory monitoring of blood pressure in normal pregnancy.

The definition of hypertensive disorders in pregnancy is plagued by many difficulties, in part related to the limits of intermittent clinic readings of blood pressure. In order to better define the evolution of arterial blood pressure in normal subjects during normal pregnancy, casual and ambulatory (Spacelabs 90207, n = 22 or Diasys 200, n = 26) measurements of blood pressure were performed at gestational months 3, 6, and 9, in 48 normal women aged 18 to 39, both nulliparas (n = 19) and multiparas (n = 29). Ambulatory blood pressure levels were lowest in the first gestational trimester (24-hour mean: 104 +/- 8/63 +/- 6 mm Hg) and rose by a small increment during the last trimester (109 +/- 8/67 +/- 7 mm Hg at 8 months). Mean daytime ambulatory pressure was almost superimposable to clinic measurements at the three time points. A day-night variation in blood pressure level was detectable in all subjects at each recording. It is concluded that during normal pregnancy, ambulatory blood pressure levels were highest in the day and lowest at night at all gestational ages and increased only minimally before the ninth month. Reference values, as defined by the percentile distribution of daytime and nighttime systolic and diastolic blood pressure, may help define more precisely an alteration in the level and/or the circadian variation of arterial blood pressure during abnormal pregnancies.

[Comparative effects of angiotensin converting enzyme inhibitors and calcium antagonists on pulse pressure and blood pressure variability, based on ambulatory measurements in 236 mild to moderate hypertensive patients]. / Effets comparés des inhibiteurs de l'enzyme de conversion et des inhibiteurs calciques sur la pression pulsée et la variabilité tensionnelle mesurées en ambulatoire chez 236 hypertendus légers à modérés.

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.

Early disturbances of ambulatory blood pressure load in normotensive type I diabetic patients with microalbuminuria.

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.

[Methods of computerized approach of dysautonomia from a non-invasive pressure signal]. / Méthode d'approche automatisée de la dysautonomie à partir d'un signal de pression non invasif.

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.

[Comparative effects of angiotensin converting enzyme inhibitors and calcium inhibitors related to baseline ambulatory blood pressure. A French multicenter study]. / Effets comparés des inhibiteurs de l'enzyme de conversion et des inhibiteurs calciques en fonction du niveau tensionnel ambulatoire de base. Etude multicentrique française.

OBJECTIVE: This multicenter study was aimed at determining whether the baseline ambulatory blood pressure (BP) level does influence the efficacy of angiotensin-converting enzyme inhibitors (CEI) and that of calcium antagonists (CA) to the same degree. METHODS: The BP recordings of 236 patients with mild to moderate hypertension were reviewed: these subjects previously entered clinical trials comprising a mean 2-week placebo period and a mean 6-week active treatment phase (CEI = 115, CA = 121). The 24-hour baseline ambulatory BP was considered as high when greater than 139/87 mmHg, according to Staessen's meta-analysis. RESULTS: In the patients with an high baseline ambulatory BP, CEI and CA have had roughly a similar effect (reduction in systolic = 9.5 +/- 7.8% vs 7.7 +/- 6.3%, NS; reduction in diastolic = 9.8 +/- 8.6% vs 8.3 +/- 5.8%, NS). Conversely, the patients with a baseline ambulatory BP level lower than or equal to 139/87 mmHg experienced a greater reduction in ambulatory BP with CEI than with CA (systolic = 7.9 +/- 7.0% vs 0.6 +/- 6.7%, p = 0.0001; diastolic: 5.0 +/- 7.4% vs 1.9 +/- 7.6%, p = 0.040). Finally, further analysis found the threshold of drug efficacy to be 120/80 and 135/85 mmHg in CEI and CA patients respectively. CONCLUSIONS: 1) CEI are more effective than CA in patients with a low ambulatory BP only. 2) The risk of a visceral hypoperfusion seems however to be limited, since CEI do not reduce diastolic ambulatory BP further, when its baseline level is lower than 80 mmHg.

Comparison of angiotensin-converting enzyme inhibitors and calcium antagonists in the treatment of mild to moderate systemic hypertension, according to baseline ambulatory blood pressure level.

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)

[Study of the 24 hour blood pressure profile in normotensive type I diabetic patients]. / Etude du profil tensionnel des 24 heures de sujets diabétiques de type I normotendus.

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)

Day and night blood pressure values in normotensive and essential hypertensive subjects assessed by twenty-four-hour ambulatory monitoring.

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.

[Enzymatic characteristics of the catalytic subunit of the protein kinase complex of human lymphocytes]. / Caractéristiques enzymatiques de la sous-unité catalytique dans le complexe de la protéine-kinase du lymphocyte humain

In earlier reports we have shown the existence in human lymphocytes homogenate, of a cyclic-AMP dependent protein-kinase activity. We demonstrate by affinity chromatography that two subunits display respectively cyclic-AMP binding and phosphorylating properties. Divalent cations such as Ca++, Mg++ or Mn++ are required for enzymatic activity. ATP which is an obligatory cosubstrate acts as an inhibitor when its concentration is higher than 10(-6)M.