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.     

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.     

Uncontrolled hypertension due to volume overload contributes to higher left ventricular mass index in CAPD patients.

BACKGROUND: Hypertension (HT) is common in patients on continuous ambulatory peritoneal dialysis (CAPD) and is responsible for increased cardiovascular morbidity and mortality. In this study, we aimed to determine the prevalence of 'uncontrolled HT' during background therapy in CAPD patients by using office measurements and ambulatory blood pressure monitoring (ABPM). We further determined whether intravascular volume status, assessed by inferior vena cava diameter (IVCD) index, contributes to higher blood pressure (BP) and increased left ventricular mass index (LVMI). METHODS: Seventy-four CAPD patients were included in the final analysis. All patients underwent echocardiographic examination and received ABPM. Patients undergoing CAPD were categorized into two groups: 'uncontrolled HT' (Group A) and 'normotensive and controlled HT' (Group B). Intravascular volume status was determined using the IVCD index and collapsibility index (CI) on the same day as ABPM. RESULTS: The prevalence of HT was 84% when using office measurements and 82% when using daytime ABPM. Daytime BP was 147/92 mm Hg by office measurements and 145/91 mm Hg by ABPM (P>0.05). The prevalence of 'uncontrolled HT' measured by ABPM was 73% (n=54). Patients with uncontrolled HT (Group A) were taking more antihypertensive medications than patients with 'normotension and controlled HT' (Group B, n=20; 1.0+/-0.8 vs 0.5+/-0.7, P=0.008). The IVCD index was higher in Group A than in Group B (9.2+/-2.1 vs 7.7+/-1.9 mm/m(2), P=0.007). There was no correlation between IVCD index and office BP, ABPM measurements or LVMI. The LVMI was also higher in Group A than in Group B (145+/-39 vs 118+/-34 g/m(2), P<0.01). Stepwise multiple regression analysis revealed that 24 h diastolic BP and haemoglobin were independent determinants of LVMI. CONCLUSION: Uncontrolled HT on background therapy is highly prevalent among volume overloaded CAPD patients. Further long-term prospective studies examining effects of salt restriction and ultrafiltration on BP control and left ventricle wall thickness are warranted.     

Effect of Exercise Training on Interdialytic Ambulatory and Treatment‐Related Blood Pressure in Hemodialysis Patients

Background: Exercise training improves blood pressure (BP) in the general population, but prior studies in hemodialysis (HD) patients only used pill counts or treatment‐related BPs. We evaluated the effect of 3 to 6 months of intradialytic exercise training on ambulatory blood pressure (ABP) and treatment‐related pre‐ and postdialysis BP. Patients and Methods: Nineteen chronic HD patients trained with an exercise bicycle for 30 to 60 min in the first 1 to 2 hr of each of thrice weekly HD. Interdialytic 44‐hr ABP was performed a week before training began and repeated at 3 and 6 months. Pre‐ and post‐HD systolic and diastolic BP and pre‐ and post‐HD weight were recorded for 2 months prior to training, throughout the training, and, if available, for the 2 months after training ended. BP medications were recorded throughout. Body composition by bioimpedance, and norepinephrine and epinephrine levels by RIA were done at 0, 3, and 6 months. Results: Thirteen subjects who completed at least 3 months of training exercised 90% of HD sessions for 56 min ± 23 SD each. Systolic and diastolic 44‐hr interdialytic ABP fell during training (systolic 138.4 mmHg ± 19.6 vs. 125.7 mmHg ± 20.0 vs. 125.9 mmHg ± 22.9; diastolic 83.2 mmHg ± 10.2 vs. 74.7 mmHg ± 9.0 vs. 73.9 mmHg ± 11.8 at 0, 3, and 6 months; p < .05 ANOVA). Norepinephrine and epinephrine levels did not independently predict systolic BP. Pre‐HD systolic BP was stable during the pretraining period, fell significantly during the training period (p < .03), and returned toward preexercise levels during the posttraining period (p < .001). Pre‐ or postweight, erythropoietin dose, total body water, and number of BP meds were unchanged. Conclusion: Exercise training during HD significantly improves both interdialytic ABP and treatment‐related BP.     

Blood pressure assessment in haemodialysis patients: Comparison between pre-dialysis blood pressure and ambulatory blood pressure measurement

Aim: Hypertension is common in haemodialysis (HD) patients. Determining the most appropriate method of blood pressure (BP) measurement, representative of target organ damage, is still an issue. BP variations between pre‐ and post‐HD treatment, or between on‐dialysis day and off‐dialysis day, are common. The aim of this study was to examine the possible differences between pre‐HD office BP (OBP) levels, inter‐HD (iHD) or HD day 24 h ambulatory BP measurement (ABPM) with 48 h ABPM, where the latter was considered the gold standard. Methods: 163 HD patients were studied. BP was monitored consecutively for 48 h with a Takeda TM2421 device, then sub‐analysed into two periods of 24 h: HD and iHD day. An average of 12 sessions pre‐HD OBP measurements was determined. Results: OBP significantly overestimates systolic (SBP) and diastolic BP (DBP) when compared with 48 h ABPM. SBP and DBP are significantly higher on iHD day than on HD day: 141.2 ± 20.8 versus 137.9 ± 20.9, and 77.1 ± 11.1 versus 76.1 ± 10.9 (P < 0.01). No differences of SBP night/day ratio were reported between 48 h ABPM and iHD 24 h ABPM or HD 24 h ABPM. The highest correlations were reported between 48 h SBP/DBP with iHD or HD 24 h ABPM (r² = 0.95, P < 0.001), while the lowest between 48 h SBP/DBP and OBP (r² = 0.40, P < 0.01, r² = 0.12, P < 0.01). The narrowest limits of agreement using the Bland and Altman test were reported between 48 h SBP or DBP and 24 h iHD or HD day ABPM. Considering 48 h ABPM, 80.5% of patients had BP higher than the norm, compared with 61.7% of patients in the case of OBP (χ² = 13.28, P < 0.001). The sensibility for detecting hypertension for iHD day 24 h ABPM was 98.4%, with specificity of 90%. The sensibility of 24 h HD day ABPM was 90.3%, with specificity 96.6%. In the case of OBP, sensibility and specificity were considerably lower, that is, 72.6% and 83.3% respectively. Conclusion: Significant differences are shown between OBP and 48 h ABPM in the recognition of a hypertensive state. OBP measurement has a lower sensibility and specificity than 24 h ABPM, which remains a valid alternative approach to 48 h ABPM in HD patients. Errors of OBP estimation should be taken into account, with possible negative impact on treatment strategies and epidemiology studies.     

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.     

Morning blood pressure is useful for detection of left ventricular hypertrophy in hemodialysis patients

Background

When diagnosing hypertension (HT) it is essential to determine not only the level of raised blood pressure (BP), but also how the condition relates to organ damage. The best time to measure BP for diagnosing HT in patients on hemodialysis (HD) remains unclear.

Methods

A total of 100 HD patients (mean age 63.8?years, 60 males) were studied. Left ventricular hypertrophy (LVH) was detected by echocardiography and BP monitored for 1?week at 20 different times in the morning and night, before and after dialysis. We also checked for masked HT, i.e., patients with weekly morning HT, but not pre-dialysis HT.

Results

Average BP for the week was 141.9?±19.0/79.6?±?10.6?mmHg, with 68 patients classified as hypertensive. Average morning BP was 144.6?±?19.8/81.7?±?11.3?mmHg, and 71 patients had weekly morning HT. In addition, 62 patients had LVH and 51 patients had relative morning HT. Multiple logistic analyses showed that LVH was associated with weekly morning HT, morning HT on HD and non-HD days, average HT, and relative morning HT. However, evening, pre-dialysis, and post-dialysis HT showed no association with LVH. Masked HT was found in 20?% of patients. If HT had been diagnosed using only pre-dialysis BP, 20 of the 71 patients with weekly morning HT would not have been detected.

Conclusion

Morning BP is useful for detecting LVH in HD patients. Monitoring of morning BP may be superior to measurements taken at other times for diagnosing HT.     

Blood pressure profile in renal transplant recipients and its relation to diastolic function: tissue Doppler echocardiographic study

Hypertension is a common complication after renal transplantation and is associated with increased risk of cardiovascular disease. The aim of the current study was to investigate the diurnal blood pressure pattern and its relation to structural and functional cardiac changes in renal transplant recipients. Sixty-six stable renal transplant patients (34 female, 32 male), aged 7 to 25 years (mean 17.4 ± 4.3 years) were enrolled in this study. Cardiac function assessed by tissue Doppler echocardiography and blood pressure measurement performed using both the ambulatory and the casual method. Hypertension was demonstrated in 57% of recipients by the casual method and in 75.7% by ambulatory blood pressure monitoring (ABPM). The efficacy of BP control among patients on antihypertensive drugs was 60%. The prevalence of non-dipping was 73%. There was significant inverse correlation between systolic or diastolic day-time or night-time BP index and post-transplant duration (p < 0.001, r =−0.386), but no correlation between ABP parameters and BMI, gender, and eGFR. There was a significant relationship between all ABP parameters and left ventricular mass index (LVMI) (p = 0.025–0.007, r = 0.28–0.38). LVMI was significantly higher in hypertensive than in normotensive cases (p = 0.034). There was no difference in diastolic function between hypertensive and normotensive patients or between patients with and without left ventricular hypertrophy (LVH). In conclusion, our study showed the advantage of ABPM over the casual method of diagnosis of hypertension. LVH is common in transplant patients and is likely associated with arterial hypertension. Hypertension and LVH cannot differentiate transplant patients with diastolic malfunction.     

Impact of volume status on blood pressure and left ventricle structure in patients undergoing chronic hemodialysis

In this study, we aimed to examine the impact of volume status on blood pressure (BP) and on left ventricular mass index (LVMI) in chronic hemodialysis (HD) patients. This study enrolled 74 patients (F/M: 36/38, mean age 53.5 ± 15.3 years, mean HD time 41.5 ± 41 months) that were on HD treatment for at least 3 months. Demographics, biochemical tests, hemogram and C-reactive protein levels, mean interdialytic weight gain (IDWG), mean percentage of ultrafiltration (UF), and intradialytic complications such as hypotension and cramps were determined. Mean values of predialysis and postdialysis BP measurements were recorded a month before echocardiographic examination. On the day after a midweek dialysis session, 24 h ambulatory BP monitoring (ABPM) and echocardiographic examination were made concurrently. The patients were classified into two groups according to volume status: normovolemic (group 1; 14F/24M, mean age 50 ± 16.7 years, mean dialysis time 47.7 ± 47.7 months) and hypervolemic (group 2; 15F/21M, mean age 57.3 ± 12.7 years, mean dialysis time 34.9 ± 32 months). HD duration, IDWG, UF, and interdialytic complication rates were similar between the two groups (p < 0.05). Eleven patients (28.9%) of group 1 and 8 patients (22.2%) of group 2 showed dipper (p?=?0.50). Valvular damage was more common in group 2 (p?=?0.002). Whereas 33 patients (91.7%) had left ventricular hypertrophy (LVH) in group 2, 21 patients of the group 1 (55.3%) had LVH (p < 0.001). Although LVMI showed a significant positive correlation with cardiothoracic index, predialysis and postdialysis BP, IDWG, UF, daytime and nighttime BP measurements of 24 h ABPM, a significant negative correlation was seen with Kt/V urea and serum albumin levels. In conclusion, increased IDWG and UF and elevated BP are independent predictors of LVH for HD patients. Increased volume status leads to IDWG and elevated BP and eventually causes severe LVMI increases.     

Home systolic blood pressure on the morning of dialysis days has prognostic impact for hypertensive hemodialysis patients

Background

Hypertension is a leading cause of cardiovascular (CV) disease in the general population. Although hypertension is very common in maintenance hemodialysis (HD) patients, adequate blood pressure (BP) values and measurement timing have not been defined.

Methods

A total of 49 hypertensive HD patients were recruited. Average age was 63?±?11?years, and duration of dialysis therapy was 6.2?±?4.2?years. Dialysis unit BPs and various types of home BPs were separately measured, and which BPs were the most critical markers in evaluating the effect of hypertension on left ventricular hypertrophy and CV events was investigated.

Results

Predialysis systolic BPs were not correlated with any home BPs. Left ventricular mass index (LVMI) had a significant positive correlation with home BPs, especially morning systolic BPs on HD days (P?P?Conclusions Home BP, especially systolic BPs in the morning on HD days, can provide pivotal information for management of HD patients.     

Effect of exercise training on interdialytic ambulatory and treatment-related blood pressure in hemodialysis patients

BACKGROUND: Exercise training improves blood pressure (BP) in the general population, but prior studies in hemodialysis (HD) patients only used pill counts or treatment-related BPs. We evaluated the effect of 3 to 6 months of intradialytic exercise training on ambulatory blood pressure (ABP) and treatment-related pre- and postdialysis BP. PATIENTS AND METHODS: Nineteen chronic HD patients trained with an exercise bicycle for 30 to 60 min in the first 1 to 2 hr of each of thrice weekly HD. Interdialytic 44-hr ABP was performed a week before training began and repeated at 3 and 6 months. Pre- and post-HD systolic and diastolic BP and pre- and post-HD weight were recorded for 2 months prior to training, throughout the training, and, if available, for the 2 months after training ended. BP medications were recorded throughout. Body composition by bioimpedance, and norepinephrine and epinephrine levels by RIA were done at 0, 3, and 6 months. RESULTS: Thirteen subjects who completed at least 3 months of training exercised 90% of HD sessions for 56 min +/- 23 SD each. Systolic and diastolic 44-hr interdialytic ABP fell during training (systolic 138.4 mmHg +/- 19.6 vs. 125.7 mmHg +/- 20.0 vs. 125.9 mmHg +/- 22.9; diastolic 83.2 mmHg +/- 10.2 vs. 74.7 mmHg +/- 9.0 vs. 73.9 mmHg +/- 11.8 at 0, 3, and 6 months; p < .05 ANOVA). Norepinephrine and epinephrine levels did not independently predict systolic BP. Pre-HD systolic BP was stable during the pretraining period, fell significantly during the training period (p < .03), and returned toward preexercise levels during the posttraining period (p < .001). Pre- or postweight, erythropoietin dose, total body water, and number of BP meds were unchanged. CONCLUSION: Exercise training during HD significantly improves both interdialytic ABP and treatment-related BP.     

Aortic stiffness, left ventricular hypertrophy and weekly averaged blood pressure (WAB) in patients on haemodialysis.

BACKGROUND: In haemodialysis (HD) patients, no consensus has been reached with regard to the desired blood pressure (BP) level and when or how BP should be monitored. Moreover, BP variability over a period of 1 week has not been well studied in HD patients. METHODS: The present study is an observational study that comprised 101 HD patients (65 males and 36 females). We used daily home blood pressure (HBP) monitoring to record a total of 20 points of BP over a period of 1 week, including measurements of the wake-up and night BPs; this was in addition to the BP recorded before and after each HD session that occurred three times a week. The average of these 20 BP measurements was defined as the weekly averaged blood pressure (WAB). Finally, we studied the relationship between the WAB and left ventricular hypertrophy (LVH) or aortic stiffness measured by baPWV. RESULTS: The systolic (142.5+/-19.5 mmHg) and diastolic (.78.8+/-9.9 mmHg) WABs were almost consistent with the wake-up BP on the day after the midweek dialysis session (R2=0.709 and 0.775, respectively). The WAB showed significant positive correlations with the left ventricular mass index (LVMI) (R=0.387, P<0.001) and baPWV (R=0.226, P<0.05), whereas the predialysis systolic BP did not show a significant positive correlation with the LVMI. CONCLUSION: The WAB is a useful marker for evaluating the BP of HD patients and correlates well with the LVMI or baPWV.     

Prediction of hypertension in chronic hemodialysis patients.

BACKGROUND: There are no universally accepted criteria for the diagnosis of hypertension in hemodialysis (HD) patients. We sought to determine the clinical performance of predialysis and postdialysis systolic and diastolic blood pressure values (BPs) in diagnosing hypertension or assessing its control. METHODS: Seventy patients [77% African American, 46% females, mean age 59 +/- 17 (SD) years, 34% diabetics] on chronic HD underwent a single 44-hour interdialytic ambulatory blood pressure monitoring (ABPM) and concomitant recording of BP by conventional syphygmomanometer in the HD unit for two weeks. Hypertension was defined as systolic BP (SBP) > or =135 mm Hg or diastolic BP (DBP) > or =85 mm Hg on an average 44-hour ABPM. RESULTS: Average ABP was 144 +/- 22/81 +/- 11 mm Hg. Seventy-three percent of the patients had systolic hypertension; 40% had diastolic hypertension, and 24% were normotensive or had well-controlled BP. Area under the curve of receiver operating characteristic (ROC) curves exceeded 80% for all BPs, but the thresholds for best sensitivity and specificity were markedly different for predialysis and postdialysis BPs. A two-week averaged predialysis BP of > 150/85 mm Hg or a postdialysis BP of > 130/75 mm Hg had at least 80% sensitivity in diagnosing hypertension. Specificity of at least 80% was achieved if predialysis BP of > 160/90 mm Hg or postdialysis BP of > 140/80 mm Hg was used. There was poor agreement between HD unit BP and ABP values. CONCLUSIONS: HD unit BP values can be used to identify the presence or absence of hypertension, although prediction of ambulatory BPs from HD unit BP values cannot be made reliably in individual patients.     

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.     

Ambulatory blood pressure monitoring in renal transplant patients: should it be routinely performed?

Introduction

Arterial hypertension is common among kidney transplant patients. It increases cardiovascular risk and is a factor for progression of renal failure. Our objective was to perform ambulatory blood pressure monitoring (ABPM) in renal transplant patients with office hypertension.

Methods

Patients were divided into 2 groups according to their mean ABPM blood pressures with treatment: well-controlled hypertension (blood pressure [BP] <130/85 mmHg), and poorly controlled hypertension (BP > 130/85 mmHg). A “nondipper pattern” was defined as a decrease of <10% or an increase, and a “raiser pattern,” in which mean blood pressure was greater during the nocturnal than the diurnal period. “White coat effect” was considered when the mean of 3 BP measurements in the clinic was >140/90 mmHg among well-controlled hypertensive patients as documented by ABPM.

Results

ABPM was performed in 53 patients: 25 (47%) “well-controlled hypertensives” and 28 (53%) “poorly controlled hypertensives.” Of the latter, 24 (85%) showed a nondipper or raiser pattern with only 4 revealing dipper patterns. We compared well-controlled with poorly controlled hypertensives. The latter cohort were older (54.4 ± 9.3 vs 45.5 ± 13.8 years; P = .009), received grafts from older donors (56.7 ± 15.0 vs 45.8 ± 17 years; P = .02); had worse renal function measured by serum creatinine (1.7 ± 0.5 vs 1.4 ± 0.4 mg/dL, P = .03) or the Modification of Diet in Renal Disease (MDRD) = 4 formula (41.8 ± 14.0 vs 55.4 ± 20.5 mL/min/1.73 m²; P = .009), and displayed more proteinuria (0.30 ± 0.33 vs 0.18 ± 0.10 g/d, P = .08). Nondipper or raiser patients showed a higher mean body mass index (27.1 vs 21.7 kg/m²; P = .04). Among 25 well-controlled patients, 11 presented “white coat phenomenon.”

Conclusion

We observed an important “white coat” effect, a large prevalence of uncontrolled nocturnal hypertension, and a small but important incident of “masked hypertension.” Factors related to hypertension control were patient age, donor age, renal function, induction use, and proteinuria.     

A registry of haemodialysis patients and the progress of haemodialysis services in Lithuania.

Background. Until 1990, haemodialysis (HD) in Lithuania wasunderdeveloped, but after independence, development of HD started.Until 1996, no precise data about HD patients in Lithuania wereavailable. In order to create a registry of HD, we started tocollect data about dialysis services and HD patients in 1996.Every collection of data was followed by distribution and discussionof the results within the nephrological community. This studydescribes the changes of Lithuanian HD between 1996–2002. Methods. Between 1996 till 2002 all HD centres in Lithuaniawere annually visited and data were collected about all HD patients(response rate of 100%). The evaluation of the results duringour observational study was made according to the European BestPractice Guidelines. During annual conferences for nephrologists,the guidelines and data of our HD registry were presented. Results. There was an increase in the number of HD stations(from 25 p.m.p. to 75 p.m.p., P<0.001), in HD patients (from60 p.m.p. to 237 p.m.p., P<0.001) and in the incidence ofnew HD patients (from 54.3 p.m.p. to 103 p.m.p., P<0.01).The mean age of HD patients increased from 47.2±16.1years in 1996 to 56.0±14.9 in 2002 (P<0.001). Themain underlying cause of ESRD was chronic glomerulonephritis,but its rate decreased from 54.5% in 1996 to 27.5% in 2002 (P<0.001).The percentage of diabetics increased from 7.1% to 16.4%, P<0.05,and in hypertensive nephropathy from 3.1% to 10.9%, P<0.05.We observed improvement of the quality of HD in Lithuania duringthese 5 years. The percentage of patients on bicarbonate HDincreased from 7.1% in 1996 to 100% in 2002 (P<0.001). Thepercentage of patients receiving more than 12 h HD/week increasedfrom 30.8% in 1996 to 53.5% in 2002 (P<0.001). The mean Kt/Vin 1999 was 0.81±0.53, but it increased in 2002 to 1.22±0.27,P<0.001. In 2002, 84.6% of all HD patients were examinedfor HB_sAg, 82.3% for anti–HCV, 31.2% for anti-HB_s and57.1% for anti-HB_c. The percentage of patients receiving phosphatebinders increased from 65.2% in 1996 to 84.4% in 1997 and 90.5%in 2002. Serum parathyroid hormone (PTH) levels were measuredin 27.3% of HD patients in 1999 but in 85.2% of patients in2002. The mean haemoglobin (Hb) concentration increased from92±15.4 g/l to 105±14.7 g/l; the percentage ofpatients with Hb>100 g/l increased from 27.5% to 64% in 2001.The percentage of HD patients receiving epoetin was 94.6% in2001 as compared with 78% in 1997. There was a marked increasein the use of intravenous iron (from 7.5% patients in 1997 to70.8% in 2000). The mean weekly dose of Epo was lower in HDpatients receiving intravenous iron than in patients receivingoral iron. Conclusions. Over the period of 1996–2002 the HD servicessignificantly expanded in Lithuania. The introduction of EuropeanBest Practice Guidelines and the establishment of a HD registrywith feedback of the results stimulated the significant progressin the quality of HD and in the management of the patients.     

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.     

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.     

Ambulatory blood pressure monitoring in patients receiving long, slow home haemodialysis.

BACKGROUND: Good blood pressure (BP) control has been reported previously in haemodialysis (HD) patients receiving 8-h dialysis sessions. Home HD allows patients to dialyze for long periods, but there are few data on the BP control achieved by these patients. We studied BP control, using ambulatory blood pressure monitoring (ABPM), in our home-HD patients who were receiving long-hours dialysis. METHODS: Twenty-four patients aged 52.7+/-11 years underwent ABPM. They had been on home HD for 52.9+/-39 months and dialysed for 7.2+/-1.1 h thrice weekly. Two patients were taking antihypertensive drugs. Historical data on BP and weight gains were obtained from the patients' own records. Left ventricular (LV) mass was assessed by echocardiography and total body water (TBW) by bioelectrical impedance. RESULTS: The mean 24-h BP was 129+/-17 mmHg (systolic) and 83+/-14 mmHg (diastolic). The daytime BP was 131+/-17 mmHg (systolic) and 84+/-14 mmHg (diastolic), while the night-time BP was 126+/-22 mmHg (systolic) and 81+/-17 mmHg (diastolic). Six patients (25%) had a normal circadian BP rhythm, but the rest showed a subnormal fall or an increase in BP at night. Mean 24-h BP did not correlate significantly with time on dialysis, dialysis session length, Kt/V, haemoglobin, interdialytic weight gain, or TBW. Twenty-one patients (87%) had LV hypertrophy and 16 of these had diastolic dysfunction. LV mass index was inversely correlated with nocturnal BP fall (r=-0.54, P=0.03). Non-dippers had been treated longer than dippers (29 vs 59.2 months, P=0.03) but they were similar in respect to age, dialysis session length or Hb concentration. CONCLUSIONS: Long, slow haemodialysis at home provides satisfactory daytime BP control in the majority of patients without the need for antihypertensive drugs but abnormal circadian BP rhythm and LV hypertrophy remain common.     

Monitoring of iron requirements in renal patients on erythropoietin

We studied 38 patients (9 haemodialysis, 18 peritoneal dialysis,11 advanced renal failure) over the first 12 weeks of erythropoietintherapy. In 14 iron-overloaded patients (ferritin >500 µg/l)the haemoglobin (±SEM) increased from 6.74±0.27to 9.85±0.36 g/dl (P<0.0001) entirely by mobilizingiron reserves (reduced from 1,220±73 to 739±111mg, P<0.0001). In the 24 non-overloaded patients (ferritin<500µg/l) the haemoglobin rose similarly from 7.04±0.18to 10.70±0.36 g/dl (P<0.0001), partly from iron reserves(depleted from 200±74 to –44±77mg, P=0.016)and partly from oral iron supplements (305±110 mg). Inthe overloaded patients the ferritin declined from 1057 µg/l(geometric mean, range 504–3699) to 317 µg/l (42–1505,P<0.0001). In the non-overloaded patients it declined from82 µg/l (8–461) to 45 µg/l (5–379, P=0.016).The transferrin saturation (TS) in the overloaded patients appearedto decline from 38.3±7.2% to 24.0±3.7% but thiswas not statistically significant. In the non-overloaded theTS was unchanged (23.3±2.4 before and 28.1±3.6%after treatment). Considering all 38 patients together, thehaemoglobin correlated negatively with the ferritin (r=0.3731,P<0.001) but not with the TS. The TS correlated with theserum ferritin initially (r=0.75, P<0.001) but not afterthe first 4 weeks. At 12 weeks, eight of 15 patients with irondeficiency (ferritin<50 µg/l) had a TS >20%, whereastwo of five patients with persistent iron overload (ferritin>500 µg/l) had a TS <20%. We conclude that (a) inpatients with iron overload, stored iron is utilizable for erythropoiesis;(b) oral iron supplements are necessary and sufficient for mostpatients without iron overload; (c) the serum ferritin is abetter indicator of iron status than the TS for renal patientson erythropoietin.