Peter Baumgart

Blood Pressure Elevation during the Night in Chronic Renal Failure, Hemodialysis and after Renal Transplantation

Diurnal blood pressure variation was studied by ambulatory 24-hour monitoring in patients with advanced chronic renal failure (n = 20), on chronic hemodialysis (n = 20), after renal transplantation (n = 21) and in matched control groups without renal disease. Nocturnal blood pressure reductions were significantly blunted in all patient groups as compared with the respective control groups. In almost none of the 61 controls did the mean values during nighttime (8 p.m.-8 a.m.) exceed the mean day time values (8 a.m.-8 p.m.). In 10 of the 61 renal patients blood pressure was higher during the night. In patients with chronic renal disease nocturnal blood pressure elevation may be diagnosed by ambulatory 24-hour monitoring. This may require adaptation of antihypertensive treatment.

Twenty-four-hour blood pressure is not dependent on endogenous circadian rhythm.

The effects of shifted working and sleeping phases on the diurnal blood pressure rhythm were investigated in 15 physically working industrial shift workers at a slowly rotated three-shift system. Ambulatory 24-h blood pressure monitoring was performed during the morning and night shifts. In the two shifts the mean 24-h blood pressure was identical. There were no differences in the blood pressure levels in the sleeping phases or in the working periods between the two 24-h cycles. Diurnal blood pressure fluctuations had equal amplitudes. Corresponding to the lag between the working period there was a phase difference of 8 h between the 24-h blood pressure curves. At this lag, there was a high correlation between the mean hourly blood pressure values (r = 0.683). Twenty-four-hour blood pressure curves during the first and last day of a night shift were nearly equal. Thus the effects of shift rotation on the 24-h blood pressure profile were fully expressed within the first 24 hours. The immediate and complete adaptation of the 24-h blood pressure curve to shifted activity and sleeping phases indicates that activity determines the diurnal blood pressure profile. The blood pressure is largely independent of internal circadian rhythm.

Ambulatory blood pressure in normotensive and hypertensive subjects: Results from an international database

Objective To delineate more precisely an operational threshold for making clinical decisions based on ambulatory blood pressure (ABP) measurement by studying the ABP in subjects who were diagnosed as either normotensive or hypertensive by conventional blood pressure (CBP) measurement. Subjects: Twenty-four research groups recruited 7069 subjects. Of these, 4577 were normotensive (CBP 140/90 mmHg), 719 were borderline hypertensive (systolic CBP 141–159 mmHg or diastolic CBP 91–94 mmHg) and 1773 were definitely hypertensive. Of the subjects in the last of these categories, 1324 had systolic hypertension (systolic CBP 21 60 mmHg) and 131 0 had diastolic hypertension (diastolic CBP 295 mmHg). Combined systolic and diastolic hypertension was present in 861 subjects. Hypertension had been diagnosed from the mean of two to nine (median two) CBP measurements obtained at one to three (median two) visits. Results The 95th centiles of the ABP distributions in the normotensive subjects were (systolic and diastolic, respectively) 133 and 82 mmHg for 24-h ABP, 140 and 88mmHg for daytime ABP and 125 and 76mmHg for night-time ABP, respectively. Of the subjects with systolic hypertension, 24% had 24-h systolic ABP 4 33 mmHg. Similarly, 30% of those with diastolic hypertension had 24-h diastolic ABP 432 mmHg. The probability that hypertensive subjects had 24-h ABP below these thresholds tended to increase with age and was two- to fourfold greater if the CBP of the subject had been measured at only one visit and if fewer than three CBP measurements had been averaged for establishing the diagnosis of hypertension. By contrast, for each 1 O-mmHg increment in systolic CBP, this probability decreased by 54% for 24-h systolic ABP and by 26% for 24-h diastolic ABP, and for each 5-mmHg increment in diastolic CBP it decreased by 6 and 9%, respectively. In comparison with 24-h ABP, the overlap in the daytime and night-time ABP between normotensive and hypertensive subjects was of similar magnitude and was influenced by the same factors. Conclusions The ABP distributions of the normotensive subjects included in the present international database were not materially different from those in previous reports in the literature. One-fifth to more than one-third of hypertensive subjects had an ABP which was below the 95th centile of the ABP of normotensive subjects, but this proportion decreased if the hypertensive subjects had shown a higher CBP upon repeated measurement. The prognostic implications of elevated CBP in the presence of normal ABP remain to be determined.

Short report: Ambulatory blood pressure in normotensive compared with hypertensive subjects

Objective: To delineate more precisely an operational threshold for making clinical decisions based on ambulatory blood pressure (ABP) measurement by studying the ABP in subjects who were diagnosed as either normotensive or hypertensive by conventional blood pressure (CBP) measurement. Subjects: Twenty-four research groups recruited 7069 subjects. Of these, 4577 were normotensive (CBP ≥140/90mmHg), 719 were borderline hypertensive (systolic CBP 141–159mmHg or diastolic CBP 91–94mmHg) and 1773 were definitely hypertensive. Of the subjects in the last of these categories, 1324 had systolic hypertension (systolic CBP ≤160 mmHg) and 1310 had diastolic hypertension (diastolic CBP ≤95 mmHg). Hypertension had been diagnosed from the mean of two to nine (median two) CBP measurements obtained at one to three (median two) visits. Results: The 95th centiles of the 24-h ABP distributions in the normotensive subjects were (systolic and diastolic, respectively) 133 and 82 mmHg. Of the subjects with systolic hypertension, 24% had 24-h systolic ABP <133 mmHg. Similarly, 30% of those with diastolic hypertension had 24-h diastolic ABP <82 mmHg. The probability that hypertensive subjects had 24-h ABP below these thresholds tended to increase with age and was two- to fourfold greater if the CBP of the subject had been measured at only one visit and if fewer than three CBP measurements had been averaged for establishing the diagnosis of hypertension. By contrast, for each 10-mmHg increment in systolic CBP, this probability decreased by 54% for 24-h systolic ABP and by 26% for 24-h diastolic ABP, and for each 5-mmHg increment in diastolic CBP it decreased by 6 and 9%, respectively. Conclusions: The ABP distributions of the normotensive subjects included in the present international database were not materially different from those in previous reports in the literature. One-fifth to more than one-third of hypertensive subjects had an ABP which was below the 95th centile of the ABP of normotensive subjects, but this proportion decreased if the hypertensive subjects had shown a higher CBP upon repeated measurement. The prognostic implications of elevated CBP in the presence of normal ABP remain to be determined.

Circadian Rhythm of Blood Pressure: Internal and External Time Triggers

Diurnal blood pressure (BP) fluctuations are superimposed by a 24-h rhythm with usually lower levels during the night and higher levels during the day. In contrast to other rhythmic bioparameters, the diurnal BP rhythm is largely dependent on activity and sleep rather than on clock time. This has been demonstrated by the BP characteristics after shifted sleeping and working phases, during transition from sleep to wakefulness, and by the influence of sleep and activities on the 24-h BP curve during normal daily routines. Whereas the circadian rhythm of BP is predominantly governed by external time triggers, endogenous rhythmicity can only be detected by time microscopic analysis or in conditions where effects of external time triggers are almost excluded.

Nocturnal hypertension in renal failure, haemodialysis and after renal transplantation

Diurnal blood pressure variations in 20 patients with advanced renal failure, 20 patients on chronic haemodialysis, and 21 renal transplant recipients were compared with those of matched control groups without renal disease, using 24-h ambulatory blood pressure monitoring. Whereas the blood pressure during the day (from 8 a.m. to 8 p.m.) was roughly the same in the patients compared with their respective control groups, during the night (from 8 p.m. to 8 a.m.) it was substantially higher in all patient groups. The differences between the mean daytime and night-time values were significantly lower in the patients (P less than 0.05 to P less than 0.001). The nocturnal blood pressure decrease may be attenuated or even reversed in renal failure, in haemodialysis and after renal transplantation. In a proportion of these patients, 24-h ambulatory blood pressure monitoring showed an elevated nocturnal blood pressure, which may require some modification of treatment.

Effect of long-term hemodialysis on arterial compliance in end-stage renal failure.

To assess the influence of long-term hemodialysis on arterial compliance, the elastic vessel wall properties of the common carotid artery were determined in 20 normotensive renal transplant recipients (age 44.7 +/- 4.1 years) 8-12 weeks after first transplantation and in 10 healthy controls (age 45.9 +/- 5.2 years). Arterial distension was measured by using a multigate pulsed Doppler system, blood pressure curve was recorded by finger-plethysmography. 10 patients with a prior long-term hemodialysis of 51 +/- 11 months were compared to 10 patients with a prior short hemodialysis of 18 +/- 7 months. The patients and controls had been matched in respect of age, sex and blood pressure. In the long and short-term hemodialysis group, the proportion of patients (n = 10) with a history of mild hypertension was similar--mild hypertension for 25 +/- 10 months (n = 5) and for 27 +/- 9 months (n = 5). In the group with long-term hemodialysis, the cross-sectional compliance and the distensibility coefficient was significantly reduced in comparison to the group with short-term hemodialysis (p < 0.005) and to the control group (p < 0.001). A significant inverse correlation between the hemodialysis period and the distensibility coefficient (r = -0.59; p < 0.005) showed a decrease in arterial compliance with the length of hemodialysis treatment. The results demonstrate that vessel wall elasticity decreases with the length of hemodialysis treatment and is reduced by hemodialysis-dependent factors, which are detached from sustained arterial hypertension. As cause of reduced arterial compliance in long-term hemodialysis hypervolemia, hypercirculation and disturbed calcium-phosphate metabolism is suggested.(ABSTRACT TRUNCATED AT 250 WORDS)

Diurnal variations of blood pressure in shift workers during day and night shifts

SummaryThe dependence of blood pressure upon internal rhythms and the short-term effects of shift rota on the blood pressure were investigated in shift workers. Blood pressure was measured every 30 min using automatic recorders for 24 h in 17 physically working men in a chemical factory during their morning and night shifts. Mean 24-h blood pressures were identical in the morning and night shifts. There were no differences of the mean blood pressure between the respective sleeping phases or between the working periods. The amplitudes of circadian blood pressure variations were equal. There was a phase difference of 8 h corresponding to the lag between the working periods. At this 8-h lag the hourly means of the 24-h blood pressure were closely correlated (r = 0.69). Comparisons of 24-h blood pressure profiles during the first and last days of a night shift week showed that the effects of night work on the blood pressure were already fully developed within the first 24h (r = 0.86). Thus the diurnal variations of the blood pressure are determined by the working and sleeping periods and largely independent of endogenous rhythm. There is no short-term alteration of the mean 24-h blood pressure after shift rota.

Pneumonien bei abwehrgeschwächten Patienten: Stellenwert nicht bioptischer bronchoskopischer Untersuchungsverfahren in der Erregerdiagnostik

Bronchoscopy was performed on 101 immunocompromised patients with fever and pulmonary infiltrates. Underlying diseases were mainly hematological malignancies. In 71% of cases, etiology of pneumonia was clarified by nonbioptic bronchoscopic methods (bronchoalveolar lavage, bronchial secretions, protected specimen brush). In 51% of cases, empirical antibiotic treatment was modified following bronchoscopy. In patients with early bronchoscopy a better prognosis regarding healing and survival was observed than in those cases, where bronchoscopy was performed later during pneumonia. Bronchoalveolar lavage was particularly suited for diagnosis of Pneumocystis carinii and pneumonia due to viruses or Legionella. Sensitivity and specificity of bronchoscopy were lower for diagnosis of mycotic pneumonia and of Gram-negative or Gram-positive bacteria.SummaryBronchoscopy was performed on 101 immunocompromised patients with fever and pulmonary infiltrates. Underlying diseases were mainly hematological malignancies.In 71% of cases, etiology of pneumonia was clarified by nonbioptic bronchoscopic methods (bronchoalveolar lavage, bronchial secretions, protected specimen brush). In 51% of cases, empirical antibiotic treatment was modified following bronchoscopy. In patients with early bronchoscopy a better prognosis regarding healing and survival was observed than in those cases, where bronchoscopy was performed later during pneumonia.Bronchoalveolar lavage was particularly suited for diagnosis of Pneumocystis carinii and pneumonia due to viruses or Legionella. Sensitivity and specificity of bronchoscopy were lower for diagnosis of mycotic pneumonia and of Gram-negative or Gram-positive bacteria.

Patients With Newly Diagnosed Hypertension Treated With the Renin Angiotensin Receptor Blocker Azilsartan Medoxomil vs Angiotensin-Converting Enzyme Inhibitors: The Prospective EARLY Registry.

For patients with newly diagnosed hypertension, angiotensin‐converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) are usually the first‐line therapies. There is, however, no real‐life data regarding the relative clinical effectiveness and tolerability of either drug class. The prospective registry, Treatment With Azilsartan Compared to ACE Inhibitors in Antihypertensive Therapy (EARLY), was conducted to evaluate the effectiveness of the ARB azilsartan medoxomil (AZL‐M) vs ACE inhibitors in real‐world patients. Of the 1153 patients with newly diagnosed hypertension who were included in the registry, 789 were prescribed AZL‐M and 364 were prescribed an ACE inhibitor. After multivariate adjustment, AZL‐M was found to provide superior blood pressure reduction and better target blood pressure (<140/90 mm Hg) achievement. The proportion of patients with adverse events was not statistically different between groups. The authors conclude that in newly diagnosed hypertensive patients, AZL‐M provides superior blood pressure control with a similar safety profile compared with ACE inhibitors.