Blood pressure measurements and left ventricular mass index in hemodialysis patients

Left ventricular hypertrophy (LVH) is the most frequent cardiac abnormality in hemodialysis (HD) patients. It is related to cardiovascular diseases and is an important risk factor for mortality in HD patients. Arterial hypertension is an established risk factor for LVH in HD patients. Inferior vena cava (IVC) diameter is a good indicator of circulating fluid volume; hypervolemia is an important pathogenetic factor of hypertension in HD patients. The purpose of our study was to evaluate possible association between LVH, IVC diameter, and different blood pressure (BP) measurements in HD patients. In the present study, 85 HD patients were included. BP was measured with a standard mercury sphygmomanometer before and after the HD session; the average 1‐monthly values of the routine BP measurements were also analyzed. 24‐ and 48‐h ambulatory blood pressure measurements (ABPMs) were performed after the end of HD sessions using a noninvasive ABPM. Average values of systolic and diastolic BP were analyzed separately for the first (HD) and second (interdialytic) day ABPM and for both days together. Using echocardiography, left ventricular mass was measured and left ventricular mass index (LVMI) was calculated. Using ultrasonography, IVC diameter was measured on the interdialytic day. Using multiple regression analysis, we found statistically significant correlations between LVMI and mean monthly postdialysis systolic BP (P < 0.05) and mean 48‐h diastolic BP (P < 0.05). Only longer BP measurements (average 1‐month post‐HD and 48‐h ABPM) were associated with LVMI in HD patients.     

Abnormal circadian blood pressure regulation in children with nocturnal enuresis

Introduction: To investigate autonomic nervous system function in enuretic children by performing ambulatory blood pressure monitor (ABPM) for 24?h. Methods: Twenty-eight children ranging in age from 6 to 15 years with primary nocturnal enuresis and 27 age-matched healthy controls were enrolled and they get 24?h ABPM. Hypertension was defined as standard deviation score (SDS)?>?1.64 (i.e., >95th percentile) adjusted for gender and height. Urinalysis, urine electrolyte levels, urinary culture, and urinary system ultrasound were carried out in all children. They have also requested to have a diary about daily fluid intake and urine volume. Results: Although the mean 24-h and daytime diastolic blood pressure (BP) did not differ between the groups, systolic BP (SBP) was significantly higher in enuretic children (p?<?0.05). The mean night-time SBP, DBP values, SDS and BP loads were found to be significantly higher than those in the controls (p?<?0.01). A lack of nocturnal decrease was more prevalent in the enuretic children compared with the control subjects, the difference was statistically significant for DBP but not for SBP. Patients with elevated night-time BP load was found to have higher frequency of urinary incontinence per week as well as per night when compared with enuretic children with normal night-time BP load (r?=?0.72, r?=?0.69, p?<?0.01, respectively). Conclusion: Subtle abnormalities of circadian BP regulation in enuretic children indicated by a selective elevation of nocturnal SBP, DBP, and MAP, and attenuated nocturnal dipping may reflect sympathetic hyper activation and its possible role in pathogenesis of enuresis.     

Ambulatory blood pressure monitoring in paediatric patients treated by regular haemodialysis and peritoneal dialysis

Ambulatory blood pressure monitoring (ABPM) has been shown to be more representive of blood pressure (BP) levels than casual BP measurements in adult patients treated by haemodialysis (HD). In this study we compared ABPM using the oscillometric SpaceLabs 90207 monitor with casual BP measurements in 35 paediatric patients [17 treated by peritoneal dialysis (PD) and 18 by DH]. Heart rate and plasma concentrations of atrial natriuretic peptide were also measured. No correlations were found between ABPM and casual BP measurements, except for systolic day-time BP in PD patients (r=0.63). Seventy percent of PD and 33% of HD patients were regarded as hypertensive when evaluated by ABPM, while casual BP measurements demonstrated hypertension in 47% (P<0.05) of PD patients and in 44% (NS) of HD patients. One-third of patients were reclassified by ABPM either from normotensive to hypertensive (7/19) or from hypertensive to normotensive (5/16). BP assessed by ABPM was higher in PD than in HD patients. The physiological decline of BP at night was significant and more prouounced in PD than in HD patients. In HD patients day-time BP did not differ between the 1st and the 2nd interdialytic day, but increased in the night hours before the following dialysis session. A positive correlation was found between day-time BP and pre-dialysis plasma atrial natriuretic peptide in both treatment groups. In conclusion this study demonstrates that casual BP recordings are not representative of average BP in dialysed paediatric patients. ABPM is useful in the diagnosis and treatment of hypertension in children with endstage renal disease.     

Low-sodium haemodialysis without fluid removal improves blood pressure control in chronic haemodialysis patients

SUMMARY: Hypertension is an important and well‐established risk factor for both cardiovascular and cerebrovascular disease. Hypertension is much more common in patients on renal replacement therapy than in the general population. Up to 80% of patients on renal replacement therapy are hypertensive and about 50% of dialysis patients die from cardiovascular causes. Salt and water overload are major factors exacerbating hypertension in the dialysis population. This was a prospective crossover study of 10 patients examining the effect of haemodialysis for 2 weeks using usual (Na⁺ 138–140 mmol/L) sodium dialysate with a 2‐week period of low (reduced by an average of 5 mmol/L Na⁺ to 133 mmol/L on average) sodium dialysate on inter‐dialytic ambulatory blood pressure (ABPM) and trans‐thoracic bioimpedance (TTB). Ten patients, mean age 67 years, completed the study (two women and eight men). No patient became severely hyponatraemic during the study period. Mean 48 h inter‐dialytic blood pressure (BP) fell from 141/83 to 133/78 (P < 0.01). Mean arterial BP measured immediately prior to TTB fell from 92.8 mmHg to 87.5 mmHg (P < 0.01) during the low‐sodium haemodialysis period. Afterload (systemic vascular resistive index – SVRI) measured by TTB fell significantly during the low‐sodium haemodialysis period (SVRI on Na⁺‐140 = 3426 cf. Na⁺‐134 = 2281; P = 0.01). Dialysate sodium reduction without extra fluid removal had a beneficial effect on inter‐dialytic 48‐h blood pressure in chronic stable haemodialysis patients. Lowering dialysate sodium reduced the systemic vascular resistance index as measured by TTB. Reduction of dialysate sodium was well tolerated, although mild dizzines and cramps did occur. These data suggest that sodium overload and water overload may have independent effects on BP and that simple‐to‐achieve and modest changes in dialysate sodium could usefully augment the action of antihypertensives in dialysis patients.     

Comparison between oscillometric and auscultatory methods of ambulatory blood pressure measurement in hemodialysis patients

INTRODUCTION: 24-hour ambulatory blood pressure monitoring (ABPM) is commonly used in clinical and research practice. Different methods have been used in BP recording, cuff-oscillometric or Korotkoff sound, and validation studies during ABPM have been performed on general as well as hypertensive populations. Hemodialysis (HD) patients have a high percentage of complications, such as vascular diseases, and they are subject to hyperkinetic blood flows and abrupt body weight changes secondary to HD, which can invalidate BP recording. Therefore, we wanted to compare the 2 methods on an HD population. PATIENTS AND METHODS: We performed 86 ABPMs on 44 patients (aged 60.8 +/- 17.2 years) by using a device capable of the simultaneous recording of oscillometric and auscultatory BP (A&D Takeda TM2421). The data obtained with the 2 different ABPM methods have been compared, and the differences between auscultatory and oscillometric determinations have been analyzed, as presented by Bland and Altman [1986]. RESULTS: The percentage of valid recordings was significantly higher with the oscillometric method than with the auscultatory method (93.6 +/- 11.3% vs. 71.7 +/- 17.04%, p < 0.001). 24-hour diastolic BP and night-time systolic BP were higher when recorded with the oscillometric method (DBP = 75.4 +/- 9.6 mmHg vs. 71.8 +/- 9.6 mmHg, p < 0.001, asleep SBP = 119.7+/-23.3 mmHg vs. 116.2 +/- 25.0 mmHg, p < 0.001), and the systolic night/day BP ratio was also higher(0.92 +/- 0.10vs.0.90 +/- 0.10, p < 0.001). Finally, the BP coefficient of variation ((SD/mean BP) x 100) was higher when auscultatory determinations were used (16.1 +/- 4.6 vs. 14.6 +/- 4.9). The limits of agreement between auscultatory and oscillometric BP determinations were for SBP = -6.44; 7.84 and for DBP = -3.66; 10.86. CONCLUSIONS: Differences between 24-hour oscillometric and auscultatory ABPM were reported in HD patients: the diastolic 24-hour and asleep systolic BP values and the systolic night/day ratio obtained with the oscillometric method were significantly higher. The higher coefficient of variation reported with the auscultatory method and the wider limits of agreement suggest that the 2 methods do not fully coincide and, in our opinion, the oscillometric method is preferable, due to the higher number of 24-hour valid measurements.     

Clinical and pathological significance of circadian blood pressure rhythm change in IgA nephropathy patients with hypertension

Objective To investigate whether the clinical and pathological injury of kidney in IgA nephropathy (IgAN) patients with hypertension is associated with circadian blood pressure rhythm change, particularly with elevated nocturnal blood pressure (BP). Methods This study was a retrospective cross-sectional study. Clinic and renal histopathological injury data were obtained from 83 IgAN patients with hypertension. First, 24 h ambulatory BP monitoring (ABPM) data were analyzed. Second, all these IgAN patients were divided into two groups, elevated nocturnal BP group and nocturnal normotensive BP group, and the clinical and pathological differences between this two groups were analyzed. Third, logistic regression analysis was used to analyze the influencing factors of renal tubulointerstitial injury in IgAN patients with hypertension. At last, all these IgAN patients were divided into two groups according to the level of estimated glomerular filtration rate (eGFR), group of patients with eGFR≥60 ml?min-1?(1.73 m2)-1 and the other group with eGFR＜60 ml?min-1?(1.73 m2)-1, and the 24 h ABPM data were compared. Results (1) The proportion of non-dipper circadian rhythm of BP in IgAN patients with hypertension was 79.5%. (2) Compared with nocturnal normotensive BP group, patients in elevated nocturnal BP group had significantly higher levels of 24-hour urinary protein quantity and blood uric acid (both P＜0.05), and lower eGFR and urine osmotic pressure clinically (both P＜0.05). Index of interstitial fibrosis and tubular atrophy was significantly higher in nocturnal normotensive BP group (P＜0.05), while the proportion of glomerular ischemia lesion was not significantly different between two groups. (3) Multivariate logistic regression analysis showed that elevated nocturnal BP was an independent risk factor for severe tubulointerstitial injury of IgAN (OR=1.113, 95%CI 1.038-1.192, P=0.002). (4) Compared with the group of eGFR≥60 ml?min-1?(1.73 m2)-1, 24-hour systolic blood pressure (SBP) and diastolic blood pressure (DBP), daytime SBP and DBP, nocturnal SBP and DBP were significantly higher in group of eGFR＜60 ml?min-1?(1.73 m2)-1 (all P＜0.05). Conclusion The proportion of non-dipper circadian rhythm of BP in IgAN patients with hypertension is as high as 79.5%. Elevated nocturnal BP is associated with the severity of renal damage, and elevated nocturnal BP is an independent risk factor for severe tubulointerstitial injury in IgAN patients with hypertension. Therefore, 24 h ABPM should be emphasized, and elevated nocturnal BP should be well controlled to slow the progression of IgAN.     

Nighttime Blood Pressure Fall in Renal Disease Patients

Objective.?There are controversial reports in the prevalence of abnormal nighttime blood pressure fall in renal patients. It has been evaluated nocturnal BP in renal patients using 24 h blood pressure monitoring (ABPM) in comparison with nontreated control subjects either normotensives or hypertensives. Design and Methods.?It has been reviewed 137 ABPM studies performed in renal patients (47.8 ± 15.4 years, 76 men and 61 women). The control group includes 119 subjects without kidney disease, 65 were normotensives, and 49 were hypertensives, aged 46.8 ± 12.1 years, 59 men and 60 women. The ambulatory BP was measured noninvasively for 24 h by the SpaceLabs 90207 device programmed to measure BP every 15 min during daytime and every 20 min during nighttime. The definition of daytime and nighttime was made on the basis of wakefulness and sleep or bed rest periods, obtained from a diary kept by each subject. Results.?SBP, but not DBP, was higher (133.9/81.7) in renal disease patients when compared to nonrenal subjects (127.9/80.8, p<0.01). When the control group was split into normotensive and hypertensive patients there were still significant differences, but hypertensives had higher BP than renal disease patients (139.0/89.7, p<0.05). Nocturnal SBP fall in renal disease patients was reduced (5.8%, p<0.001) and so was DBP fall (11.1%, p<0.001) compared with the overall nonrenal patients sample (SBP 10.8; DBP 15.3%). The frequency of nondipper status in renal disease patients (39.6%) was higher than in control patients (18.4%, p<0.001). Nontreated normotensive renal disease patients did not show any difference in either SBP or DBP nighttime fall with respect to control normotensives. Neither do nontreated hypertensive renal patients as compared with control hypertensives. There were not differences between proteinuric and nonproteinuric patients in nocturnal BP fall. The same result was obtained when hypertensive and normotensive nontreated renal patients were compared. The presence of renal failure did not induce a reduction of nocturnal BP fall. Most of treated renal patients were mainly receiving drug therapy during the morning and frequently this was the single daily dose. Conclusions.?Altered diurnal rhythm should not be considered as a usual complication of renal disease. Inadequate antihypertensive pharmacotherapy could be related to the abnormalities of nighttime BP fall when it is detected.     

Blood pressure and cardiovascular involvement in children with neurofibromatosis type1

We evaluated blood pressure in a sample of patients with neurofibromatosis type 1 (NF1), using ambulatory blood pressure monitoring (ABPM), to determine whether ABPM, when compared with casual BP recordings, allowed the detection of a higher risk for hypertension. We also evaluated the correlation between BP and vascular abnormalities. We studied 69 NF1 patients (36 males and 33 females) with a mean age of 11±4 years, divided into group A, with 24-h mean systolic blood pressure (SBP) or diastolic blood pressure (DBP) <95th percentile, and group B, with mean SBP or DBP >95th percentile. Standard electrocardiography and M-mode, two-dimensional echocardiography were performed and all patients were in sinus rhythm. ABPM identified 11 hypertensive patients (16%); 5 had a mean SBP >95th percentile, 3 mean SBP–DBP >95th percentile, and 3 a mean DBP >95th percentile. Laboratory and other investigations to exclude secondary hypertension were normal. Cardiac abnormalities were found in 13 of the 69 patients (18.8%) with NF1. There were no significant clinical and cardiac differences between the normotensive and hypertensive group. Our data emphasize the importance of periodic ABPM in NF1 patients to diagnose hypertension early and avoid target organ damage and increased mortality.     

Relationship of ambulatory blood pressure monitoring data to echocardiographic findings in haemodialysis patients

BACKGROUND: The present study was performed to assess the value of ambulatoryblood pressure monitoring (ABPM) in determining the adequacyof blood pressure (BP) control, and its relationship to echocardiographicfindings in haemodialysis (HD) patients. METHODS: We studied 40 non-diabetic adult patients who had been on regularHD treatment for a median duration of 43 months. Twenty-four-hourABPM was performed using a non-invasive ABP monitor (Pressurescan,ERKA). Casual BP (cBP) was defined as the average of two measurementsobtained at two HD sessions, one preceding and one followingthe ABP recordings, and was calculated for both the predialysisand postdialysis phases. Two-dimensional and M-mode echocardiographywere performed in each patient to determine interventricularseptal thickness (IVS), left ventricular posterior wall thickness(LVPW), left ventricular fractional shortening (FS), and leftventricular mass index (LVMI) RESULTS: According to average 24-h BP levels, 50% of the patients hadsystolic hypertension (HT) (>139 mmHg), and 72.5% had diastolicHT (>87 mmHg), while only 25% had been diagnosed as HT bycBP measurements (P>0.01 and P>0.0001 respectively). Diurnalvariation in BP was not present in about 80% of the patients.Echocardiography was normal in only four patients (10%). LVMIand LV wall thickness were correlated to ABPM data better thanto cBP measurements. Using stepwise linear regression analysis,LVMI and FVS were positively correlated with systolic BP load(P> 0.0001 and P=0.0001 respectively), and LVPW was positivelycorrelated with night-time systolic BP level (P>0.001). CONCLUSIONS: ABPM is necessary to assess the adequacy of BP control, andis well correlated to end-organ damage of HT in HD patients.     

Twenty four‐hour ambulatory blood pressure profiles 12 months post living kidney donation

Small blood pressure (BP) elevations may occur post kidney donation. This prospective study determined 24‐h ambulatory BP (ABP) and other cardiovascular risk factor changes in 51 living donors over 12 months postdonation. Donors also provided 24‐h urine collections for monitoring protein and creatinine clearance, 75 g oral glucose tolerance tests (OGTT), and fasting lipids. Nondipping was defined as night‐day systolic (SBP) ratio ≥0.9. Baseline and 12‐month pre to postdonation comparisons were made both for dippers and nondippers. Of 51 donors, 35 were dippers and 16 nondippers. In these two groups, predonation 24‐h SBP were 115.2 ± 8 and 115.6 ± 10 mmHg; serum creatinine (SCr) 69.3 ± 12 and 71.1 ± 13 μmol/l; and 24‐h urine protein 0.12 ± 0.05 and 0.09 ± 0.03 g (all P = NS) while at 12 months, 24‐h SBP were 111.4 ± 11 and 114.3 ± 8 mmHg (P = 0.384), SCr 97.9 ± 16 and 97.7 ± 21 μmol/l (P = 0.810); and 24‐h urine protein 0.139 ± 0.09 and 0.111 ± 0.07 g/d (P = 0.360) respectively. The 24‐h SBP was significantly lower in the dippers at 12 months as compared with predonation (P = 0.036). OGTT and lipid profiles remained normal in both groups. Predonation nocturnal nondipping does not carry adverse postdonation consequences over 12 months.     

Office and ambulatory blood pressure elevation in children with chronic renal failure

Hypertension is a frequent complication in patients with chronic renal insufficiency (CRI) and is associated with target organ damage, including left ventricular hypertrophy (LVH). To better assess hypertension in pediatric patients with CRI, we performed 24-h ambulatory blood pressure monitoring (ABPM) and evaluated the relationship between ABPM parameters and LVH in 29 children, mean age 12.4+/-3.8 years. There was no significant difference in the frequency of hypertension comparing casual systolic blood pressure (SBP) (21%) with the mean 24-h (21%) or daytime mean SBP (21%). However, diastolic hypertension was detected more frequently using ABPM: 24% for 24-h diastolic blood pressure (DBP), 14% for daytime DBP, and 7% for casual DBP. Nighttime systolic hypertension as well as diastolic hypertension was detected in 12 (41%) children. Seventeen (59%) patients had attenuated dipping for SBP and 9 (31%) had abnormal DBP dipping. Lower SBP dipping was associated with lower glomerular filtration rate (r=0.44, P<0.05). LVH was found in 6 (21%) patients. LVM index was significantly correlated with 24-h SBP (r=0.43, P<0.05). Multiple regression analysis confirmed that higher 24-h SBP was the only independent predictor for increased LVM index (P=0.001). No significant relationship was found between LVM index and office blood pressure. These results confirm a high prevalence of blood pressure abnormalities using ABPM criteria in children with CRI and suggest that ABP may better predict end-organ damage in these patients than casual BP.     

Twenty-four-hour ambulatory blood pressure monitoring in young children

 Twenty-four-hour ambulatory blood pressure monitoring (ABPM) has many advantages for the diagnosis and follow-up of hypertension at all ages. This technique has so far not been documented as applicable to the very young. We studied the feasibility of ABPM in 61 healthy children and in 40 patients with renal diseases and/or hypertension, aged less than 6 years. A satisfactory ABPM profile (recording time = 24 h and >30 good recordings) was obtained in 77% of the healthy children. The mean number of good blood pressure (BP) measurements per 24 h increased with age from 46 (3–4 years) to 58 (6 years). The mean (±SD) systolic and diastolic BPs of healthy 3- to 6-year-old children (n = 47) were 110±5/67±5 mmHg during the day-time and 100±5/58±5 mmHg at night. In addition to the nocturnal decrease in BP, ABPM detected a second, day-time dip in BP during bed rest after lunch. Ninety percent of patients with renal disease and/or hypertension had successful ABPM recordings for 24 h, with an age-dependent increase in the mean number of reliable readings from 34 (< 2 years) to 48 (4 years). In 5 of 10 children with hypertensive results obtained by casual BP measurements, elevated BP was not confirmed by ABPM. We conclude that ABPM is a useful tool for the diagnosis and evaluation of hypertension in children under 6 years of age. Received March 5, 1996; received in revised form and accepted May 6, 1997     

Morning blood pressure at home predicts erythropoietin-induced hypertension in patients with chronic renal diseases

Background Correction of anemia by erythropoietin (EPO) is often associated with a rise in blood pressure (BP; EPO-induced hypertension). Most studies regarding EPO-induced hypertension have involved evaluation using office/clinic BP (OBP). However, recent investigations suggest that BP measured at home (HBP) may be of more importance for clinical practice in hypertension. In this context, the present study addressed whether or not HBP measured in the morning could be useful to predict EPO-induced hypertension. Methods The study involved patients with mild to moderate renal impairment who had renal anemia requiring EPO treatment. BP control was evaluated based on the relationship between OBP and HBP in the morning. The BP categories used were well-controlled BP, poorly controlled BP, hypertension with a white-coat effect (white-coat hypertension), and masked hypertension. Comparison was made of the BP categories before and after EPO treatment. Results Before EPO treatment, 38% of patients had well-controlled BP, 30% had poorly controlled BP, 20% had masked hypertension, and 12% had white-coat hypertension, revealing a predominance of morning hypertension (poorly controlled BP plus masked hypertension). Following EPO treatment, the prevalence of morning hypertension in patients with masked hypertension and poorly controlled BP increased significantly, by 5% (HBP in those with masked hypertension increased from 152 +/− 18 mmHg to 162 +/− 25 mmHg, and HBP in those with poorly controlled BP increased from 157 +/− 18 mmHg to 168 +/− 25 mmHg; P < 0.05 by paired t-test). And there was a significant decrease in the prevalence of the well-controlled category, by 8%, with an increased level of morning HBP (from 128 +/− 14 mmHg to 137 +/− 16 mmHg; P < 0.05 by paired t-test). In contrast, OBP remained unchanged in all groups. The development of EPO-induced hypertension was effectively predicted by HBP in the morning (from 62% to 72% before and after EPO treatment; P = 0.0031 by Wilcoxon's analysis), but not by OBP (from 42% to 47% before and after treatment; P = 0.1399). Conclusions The present study indicates that, despite receiving concurrent antihypertensive therapy, the majority of patients with renal disease had morning hypertension. Furthermore, HBP in the morning can be more useful than OBP to predict the development of EPO-induced hypertension in patients with renal anemia.     

Interdialysis blood pressure control by long haemodialysis sessions

High blood pressure (BP) is a major factor contributing to thehigh incidence of cardiovascular morbidity and mortality inhaemodialysis (HD) patients. According to predialysis casualBP measurements, long HD has been shown to provide good BP control. To confirm this result during the period between dialysis sessions,we performed ambulatory monitoring of BP in 91 non-selectedHD patients (mean age, 58.7 (14.1) years; 14% incidence of nephrosclerosisand diabetes mellitus; treatment duration, 93.0 (77.2) months;3x8 h/week, cuprophane, acetate buffer in 95% of the patients).Only one patient (1.1%) was receiving an antihypertensive medication. Ambulatory BP results were systolic (S) BP, 119.4 (19.9) mmHg;diastolic (D) BP, 70.6 (12.9) mmHg; mean (M) BP, 87.6 (13.9)mmHg. These values were significantly lower than the casualpredialysis BP data and close to the reference values reportedby Staessen et al. in a meta-analysis including 3476 normotensivesubjects. The MBP was inversely correlated with the treatmentduration, but not with interdialysis weight gain. The MBP increasedsignificantly in the last part of the interdialysis period,and this rise was not correlated with the interdialysis weightgain. The nocturnal/diurnal ratios for SBP and DBP for the HDpatients (0.97 and 0.92) were higher than the reference valuesreported by Staessen, (0.87 and 0.83), and argued against anocturnal decrease in BP. We found that 52.1% of the patientshad an abnormal nocturnal BP fall (MBP fall <5%). This featureworsened during the second night of the interdialysis period. We confirm that interdialysis BP in HD patients treated by longHD and without antihypertensive drugs approached the levelsobserved in a normal population. Achievement of dry weight isthought to be the cornerstone of this good result, but we cannotrule out other mechanisms such as the optimal clearance of pressormolecules. The BP rise during the interdialysis period, independentof the weight gain, argues for such an accumulation. Despitegood BP control the circadian rhythm of BP is not restored inour patients, and remains to be studied.     

糖耐量低减患者动态血压与尿白蛋白排泄率的关系

目的 探讨糖耐量低减(IGT)患者尿白蛋白排泄率(UAE)与不同血压指标的关系。方法 对44例IGT患者均进行动态血压(ABPM)监测,心血管自主神经功能测试,UAE测定。结果 与UAE正常组比较,UAE增高组ABPM多项指标增高,夜间血压降低幅度减少,24小时血压曲线平坦。UAE与夜间舒张压(DBP)、收缩压(SBP)负荷、DBP负荷、24hDBP以及24hSBP呈显著正相关,与昼夜血压差值呈显著负相关。结论 UAE增高的IGT患者已经开始出现血压的异常改变。     

Masked hypertension is prevalent in children with sickle cell disease: a Midwest Pediatric Nephrology Consortium study

Background

The prevalence of hypertension and abnormal blood pressure (BP) patterns on 24-h ambulatory BP monitoring (ABPM) remains unknown in children with sickle cell disease (SCD).

Methods

Thirty-eight asymptomatic children with sickle cell disease (SCD) (12 HbSS receiving routine care, 13 HbSC, and 13 HbSS receiving chronic transfusion therapy) underwent 24-h ABPM. Average clinic BP, demographic and biochemical characteristics were collected.

Results

Median age was 13?years (range 11?C16), body mass index (BMI) 19.1 kg/m² (range 18.2?C21.1), and 50% were male. Seventeen subjects (43.6%) had ambulatory hypertension, while 4 (10.3%) were hypertensive based on their clinic BP. Mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) dip were 8.3?±?5.9% and 14.7?±?7.6% respectively. Twenty-three subjects (59%) had impaired SBP dipping, 7 (18%) had impaired DBP dipping, and 5 (13%) had reversed dipping. Clinic and ABP classification were modestly correlated (rho?=?0.38, P?=?0.02).

Conclusion

Abnormalities in ABP measurements and patterns in children with SCD are prevalent and require more attention from heath care providers. ABPM is a valuable tool in identifying masked hypertension and abnormalities in circadian BP.     

Nighttime blood pressure fall in renal disease patients

OBJECTIVE: There are controversial reports in the prevalence of abnormal nighttime blood pressure fall in renal patients. It has been evaluated nocturnal BP in renal patients using 24 h blood pressure monitoring (ABPM) in comparison with nontreated control subjects either normotensives or hypertensives. DESIGN: AND METHODS: It has been reviewed 137 ABPM studies performed in renal patients (47.8 +/- 15.4 years, 76 men and 61 women). The control group includes 119 subjects without kidney disease, 65 were normotensives, and 49 were hypertensives, aged 46.8 +/- 12.1 years, 59 men and 60 women. The ambulatory BP was measured noninvasively for 24h by the SpaceLabs 90207 device programmed to measure BP every 15 min during daytime and every 20 min during nighttime. The definition of daytime and nighttime was made on the basis of wakefulness and sleep or bed rest periods, obtained from a diary kept by each subject. RESULTS: SBP, but not DBP, was higher (133.9/81.7) in renal disease patients when compared to nonrenal subjects (127.9/80.8, p < 0.01). When the control group was split into normotensive and hypertensive patients there were still significant differences, but hypertensives had higher BP than renal disease patients (139.0/89.7, p < 0.05). Nocturnal SBP fall in renal disease patients was reduced (5.8%, p < 0.001) and so was DBP fall (11.1%, p < 0.001) compared with the overall nonrenal patients sample (SBP 10.8; DBP 15.3%). The frequency of nondipper status in renal disease patients (39.6%) was higher than in control patients (18.4%, p < 0.001). Nontreated normotensive renal disease patients did not show any difference in either SBP or DBP nighttime fall with respect to control normotensives. Neither do nontreated hypertensive renal patients as compared with control hypertensives. There were not differences between proteinuric and nonproteinuric patients in nocturnal BP fall. The same result was obtained when hypertensive and normotensive nontreated renal patients were compared. The presence of renal failure did not induce a reduction of nocturnal BP fall. Most of treated renal patients were mainly receiving drug therapy during the morning and frequently this was the single daily dose. CONCLUSIONS: Altered diurnal rhythm should not be considered as a usual complication of renal disease. Inadequate antihypertensive pharmacotherapy could be related to the abnormalities of nighttime BP fall when it is detected.     

Comparison of ambulatory blood pressure and Task Force criteria to identify pediatric hypertension

The aim of this study was to assess the level of agreement between central European ambulatory blood pressure monitoring (ABPM) and American Task Force (TF) criteria when applied to blood pressure (BP) measurements collected by ABPM to evaluate patients with hypertension. In 169 patients, we applied both sets of criteria and calculated mean daytime and nighttime BP and daytime BP loads. The frequency of hypertension for daytime systolic BP was significantly higher when TF criteria were used (p ≤ 0.001). However, the frequency of hypertension for nighttime systolic BP was significantly increased when ABPM criteria were applied (p ≤ 0.01). Therefore, with daytime ABPM measurements, hypertension was overdiagnosed with TF criteria, while nighttime hypertension was underdiagnosed using TF criteria. In contrast with previous reports, 40% of our patients with essential hypertension showed absence of nighttime dipping, regardless of the criteria used. The number of hypertensive patients was significantly higher using ABPM compared to TF criteria when patients with BP load ≥50% were evaluated (p ≤ 0.01). Therefore, current recommendations for ABPM use in children such as to define white coat hypertension or as a screening tool to differentiate between primary and secondary hypertension need to be validated using yet to be produced normative ABPM criteria in American children.     

Does diurnal variation in blood pressure exist in CAPD patients?

The existence of diurnal variation in CAPD remains controversial.We therefore attempted to delineate the blood-pressure (BP)pattern in CAPD patients by ambulatory blood-pressure monitoring(ABPM). Initially ABPM was performed in 31 patients (21 M, 10F), mean age 65.4 years (26–87) using the Spacelabs model90207. The maximal normal BP preset on the recorder was 140/90mmHg. Daytime and night-time readings, recorded every 30 min,were defined as those from 0600 to 2100 and 2100 to 0600 hoursrespectively. Mean duration of dialysis was 15.2 months (3–76). There were 14 hypertensive patients, defined as a basal BP >140/90 mmHg, or those on antihypertens-ive medications. Takingthe group as a whole a significant difference between day andnight-time readings was found as regards minimal systolic BP(118 versus 107.6 mmHg), maximal systolic BP (181.6 versus 171.2mmHg), mean diastolic BP (83.9 versus 79.6 mmHg), and maximaldiastolic BP (121.7 versus 104.5 mmHg), P<0.05. Diurnal variation,defined in the initial study as a 10% decrease of MAP occurringduring any consecutive 4-h period, was present in 21 patients.In three the diurnal variation manifested as a paradoxical reductionof BP during the day. The only significant difference betweenthose with diurnal variation and those without was the durationof dialysis, being 19.2 ±19.9 versus 13.3 ±17.3months respectively, (P<0.05). In a second study 18 hypertensive CAPD patients were subjectedto ABPM. Nine of them had participated in the first study. Thesepatients were specifically asked to detail their periods ofsleep and arousal. Diurnal variation was here defined as a 10%decrease of MAP occurring 2 h after the onset of sleep. Diurnalvariation was found to exist in 10 patients (55%). Comparingthe day to night-time readings in this group, no significantdifferences were found in mean systolic and MAP. When, however,the arousal versus sleep period readings were compared, a significantdifference was observed in mean diastolic BP (83±14 versus77±17mmHg, P<0.01), and in the MAP (104 ± 18versus 98±20.5 mmHg, P<0.01). The mean systolic BPjust failed to reach statistical significance (141±26versus 137±30 mmHg) due probably to the small samplesize. We conclude that diurnal variation exists in the majority ofCAPD patients. Our findings support the concept that the setpoint model of diurnal variation, in which the major determinantis activity or arousal is the operative one in these patients.Due to disordered sleep patterns in patients on CAPD, diurnalvariation might thus be better elicited when taking into accounta decrease of MAP occurring during any consecutive 4-h period.     

Blunted nocturnal blood pressure decrease and left-ventricular mass in hypertensive hemodialysis patients

Left-ventricular hypertrophy (LVH) represents a frequent complication in hemodialysis (HD) patients. Hypertension is a well-known risk factor of cardiac morbidity which is present in 2 of 3 patients: among them about 60% have a blunted nocturnal decrease of blood pressure (BP). Although some large studies on essential hypertensives have documented that non-dipper patients have a higher number of cardiac events and a higher left ventricle (LV) mass than dipper ones, conflicting results have been reported for dialysis patients. Therefore, the aim of our study was to assess differences in LV mass between dipper and non-dipper hypertensive HD patients. We studied 66 patients with 24-hour ambulatory BP monitoring performed on HD and on inter-HD day. They were classified as dipper when a decrease of at least 10% of nocturnal systolic blood pressure on the inter-HD day was present. Echocardiography and bioimpedance were performed. 29% of the patients were classified as dippers and 71% as non-dippers. The 48-hour systolic and diastolic BP were not significantly different between the two groups (SBP: dipper = 144 +/- 12.9 mm Hg, non-dipper = 149 +/- 17.8 mm Hg; DBP: dipper = 80 +/- 9.9 mm Hg, non-dipper = 81 +/- 10.6 mm Hg). LV mass index (LVMi) did not differ between the two groups (dipper = 143.1 +/- 40.7 g/m(2); non-dipper = 159.4 +/- 46.3 g/m(2)). No differences were reported between dipper and non-dipper patients regarding extracellular water distribution (ECW: 48.1 +/- 7.7 vs. 49.8 +/- 10.8%). SBP night/day ratio and 48-hour SBP were not correlated to LVMi. A strong correlation was reported between ECW% and LVMi (r = 0.53, p < 0.001). In conclusion, 2 of 3 hypertensive HD patients are non-dipper, and this condition does not seem to be associated with significant differences in 48-hour blood pressure and LV mass. Volume overload appears to be the main independent determinant of LVH in these patients.