Association between extracellular water, left ventricular mass and hypertension in haemodialysis patients.

BACKGROUND: Hypertension and left ventricular hypertrophy (LVH) are present in the majority of patients undergoing haemodialysis (HD). These two pathologies persist after dialysis onset, and pharmacological therapy is often required for adequate control of blood pressure (BP). Although fluid overload is a determinant of hypertension, clinical assessment of this parameter remains difficult and unsatisfactory. Bioimpedance analysis (BIA) spectroscopy and the relative determination of extracellular water (ECW%) may provide a simple and inexpensive tool for investigating fluid overload. We studied 110 patients on thrice-weekly HD to determine whether ECW body content correlates with hypertension and LVH in this patient population. METHODS: Hypertension was determined according to the WHO criteria (office BP >/= 140/90 and/or the use of antihypertensive therapy). Twenty-four hour BP monitoring and echocardiography were performed on midweek inter-HD days. Blood chemistries, dialysis dose (spKt/V) and bioimpedance were analysed on midweek HD days. RESULTS: Hypertension was present in 74.5% of patients. There were no differences for age, spKt/V, haemoglobin, serum creatinine and residual renal function between normotensive and hypertensive patients. Twenty-four hour systolic BP (SBP), 24 h diastolic BP and 24 h pulse pressure were higher in hypertensive patients, in spite of antihypertensive therapy. LVH was present in 61.8% of patients. BIA revealed that ECW% was increased in LVH+ patients (LVH+ = 47.5 +/- 7.9%, LVH- = 42.4 +/- 6.2%, P = 0.01) and in hypertensive patients compared with normotensives (46.5 +/- 7.7% vs 43 +/- 7.2%, P = 0.02). Dry body weights and inter-HD body weight increases did not differ between hypertensive and normotensive patients nor between patients with or without LVH. ECW was correlated with SBP (r = 0.35, P < 0.01) and with left ventricular mass index (LVMi(g/sqm)) (r = 0.49, P < 0.001). A stepwise multiple linear regression model revealed that LVMi(g/sqm) was significantly correlated with ECW%, SBP and male gender (r = 0.65, P < 0.001). CONCLUSIONS: LVH and hypertension are present in a majority of HD patients and they are closely correlated with one another. We found associations between fluid load, measured by BIA and expressed as ECW, and BP and LVM.     

Is 44-hour better than 24-hour ambulatory blood pressure monitoring in hemodialysis?

The aim of this study is to evaluate if hemodialysis (HD) patients with similar blood pressure (BP) in the whole inter-HD period could have different target organ lesions and survival if the behavior of BP differs from the first to the second day of the inter-HD period. The present study compares 44-hour ambulatory BP monitoring (ABPM) patterns in 45 HD patients. Three BP patterns emerged: group A (n = 15) had similar BPs throughout (138 +/- 11/88 +/- 12 in the first 22 h vs. 140 +/- 11/87 +/- 12 mm Hg in the second 22-hour period); group B (n = 15) had a significant systolic BP rise from the first to the second period (132 +/- 15/80 +/- 12 vs. 147 +/- 12/86 +/- 13 mm Hg, p < 0.05); group C (n = 15) had significantly higher BPs (p < 0.05) than the other 2 groups throughout the whole inter-HD period, with no significant change between the 2 halves (172 +/- 14/108 +/- 12 vs. 173 +/- 18/109 +/- 14 mm Hg). Ventricular mass and survival during the 30-month follow-up period were statistically significantly better in group A, intermediate in group B and worse in group C. The data suggest that a 44-hour ABPM is more accurate than a 24-hour one in evaluating organ lesion and prognosis in HD patients.     

Profile of interdialytic blood pressure in hemodialysis patients

BACKGROUND AND METHODS: Hypertension is a common problem in hemodialysis (HD). However, its behavior during the interdialytic period is not completely known and is infrequently monitored in clinical practice. Thus, for better understanding of interdialytic blood pressure (BP), we analyzed the interdialytic blood pressure profile using 44-hour ambulatory blood pressure monitoring (ABPM) data in 71 unselected, stable HD patients. RESULTS: There was an increase in BP during the interdialytic period (awake day 1: 135/84 +/- 23/14 mm Hg; awake day 2: 140/86 +/- 22/15 mm Hg, p < 0.05; sleep day 1: 130/77 +/- 24/15 mm Hg; sleep day 2: 136/80 +/- 24/15 mm Hg, p < 0.05). The correlation between the average 44-hour BP and interdialytic weight gain (IDWG) was not significant (r = -0.07 for systolic BP and r = -0.09 for diastolic BP). The number of non-dipper patients was high, 77% on interdialytic day 1 and 83% on interdialytic day 2 for systolic BP. Uncontrolled hypertension (average 44 h BP > or =135/85 mm Hg) was diagnosed in 58 (55%) patients. Patients with uncontrolled hypertension had higher pre- and posthemodialysis BP, higher BP on each interdialytic day and night, and higher night/day diastolic BP ratio on the second interdialytic day. These patients were also taking a greater number of vasoactive medications (1.5 vs. 0.6 in those with controlled BP, p = 0.001). There were no significant differences related to kt/V, hematocrit, or weekly erythropoietin dose between patients with controlled or uncontrolled BP. Hemodialysis shift assignment (morning or afternoon) did not impact on BP levels or diurnal profile. CONCLUSION: In HD patients, interdialytic BP is often poorly controlled, there is a progressive rise in BP, and a trend toward loss of nocturnal decline in BP as the interdialytic period progresses. Further research is needed to determine whether treatment directed to interdialytic BP changes can alter outcomes in HD patients.     

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.     

Effects of short daily hemodialysis and extended standard hemodialysis on blood pressure and cardiac hypertrophy: a comparative study

BACKGROUND: Causes of hypertension and cardiac hypertrophy in hemodialysis (HD) patients are multiple, but the role of fluid overload appears to be crucial. Short daily HD (sDHD = 2 hr x 6/week) seems to allow reductions in left ventricular mass (LVM) through the reduction of extracellular water (ECW). Better cardiovascular stability during HD can be obtained with short, but more frequent HD sessions, but also by increasing the session length accompanied with a reduction in ultrafiltration (UF)/hr. Regardless of the method, the adequate reduction in extracellular volume should permit better control of hypertension and left ventricular hypertrophy (LVH). This study aimed to compare sDHD with an extended form of standard HD (eSHD = 4.5-5 hr x 3/week) on the reduction of fluid overload, blood pressure (BP) and LVM index (LVMi). Patients and methods:Twenty-four HD patients with hypertension and LVH were enrolled in a prospective non-randomized study. After a 3-month run-in period they were divided in two comparable groups: 12 patients treated with sDHD, and 12 patients treated with eSHD for 6 months. LVMi, 24 hr BP monitoring, ECW, determined with electrical bio-impedance, biochemical correlates and spKT/V were studied at the beginning of the study and 6 months later. RESULTS: The weekly session length was increased in eSHD from 722.9 +/- 7.5 to 877.3 +/- 35.5 min. ECW% was reduced similarly in the two groups (Delta ECW: eSHD = 4.6 +/- 2.4 L; sDHD = 4.1 +/- 2.3 L); 24 hr BP decreased significantly from 157/81 to 137/75 mmHg in eSHD, and from 149/79 to 128/72 mmHg in sDHD. The reduction in systolic BP was similar in the two groups (eSHD = 20.1 +/- 15.3 mmHg, sDHD = 21.2 +/- 16.7 mmHg). Finally, LVMi was similarly reduced (eSHD = 55 +/- 30.3 g/m(2), sDHD = 54.4 +/- 21.3 g/m(2). The number of antihypertensive drugs decreased significantly after ECW% reduction: only 2/10 patients on eSHD and 4/12 patients on sDHD were maintained on therapy (p = ns). Intra-dialysis hypotension episodes did not differentiate between SHD and DHD. The reduction in LVMi was significantly correlated to fluid volume changes when these were measured as phase angle (PA) with bio-impedance (r = -0.43, p < 0.05). CONCLUSIONS: In hypertensive HD patients with LVH, fluid overload is invariably present and its reduction allows the decrease of BP and LVM. These results can be obtained by forcing UF with eSHD and sDHD, but patients maintained on x 3/week schedules need longer dialysis sessions to avoid intra-dialysis symptoms.     

Impact of volume control on left ventricular hypertrophy in dialysis patients

BACKGROUND: Left ventricular hypertrophy (LVH), which strongly predicts cardiac mortality, is seen in more than 60% of end-stage renal disease patients. The aim of this study was to prospectively investigate the effect of salt restriction and strict volume control on blood pressure and LVH. METHOD: Nineteen hypertensive patients on chronic hemodialysis (HD) treatment (age 52 +/- 17 years, 7 women) were included in the study. Treatment consisted of 12-h HD per week, during which as much ultrafiltration (UF) was applied as possible without an excessive blood pressure (BP) drop. Special attention was given to dietary salt restriction. Predialysis mean BP (MBP), body weight (BW), cardio-thoracic index (CTI) and echocardiographic results were recorded at baseline and after 6 and 12 months. RESULTS: All patients reached acceptable BP (< 140/90 mmHg) within three months (10-75 days) with our strict volume control strategy. Mean pre-dialysis BP was 127 +/- 17/78 +/- 9 mm Hg at baseline, 120 +/- 9/75 +/- 6 mm Hg at the 6th month and 118 +/- 11/73 +/- 5 mm Hgat the 12th month. The incidence of symptomatic hypotension gradually decreased from a mean of 22% to 11% and 7%, respectively during follow-up. Left ventricular mass index decreased from 164 +/- 64 to 112 +/- 36 g/m2. CTI, left atrial, left ventricular systolic and diastolic diameters significantly decreased in all patients. Inter-dialytic weight gain was 930 +/- 70 g/day in the follow-up period. Hematocrit did not significantly differ at the first, second and last visits. CONCLUSION: Normal BP and improvement of cardiac structure, in particular a reduction of LVH could be reached in all our patients by intensifying salt restriction and UF.     

Regression of left ventricular hypertrophy after conversion to nocturnal hemodialysis

BACKGROUND: Left ventricular hypertrophy (LVH) is an independent risk factor for mortality in the dialysis population. LVH has been attributed to several factors, including hypertension, excess extracellular fluid (ECF) volume, anemia and uremia. Nocturnal hemodialysis is a novel renal replacement therapy that appears to improve blood pressure control. METHODS: This observational cohort study assessed the impact on LVH of conversion from conventional hemodialysis (CHD) to nocturnal hemodialysis (NHD). In 28 patients (mean age 44 +/- 7 years) receiving NHD for at least two years (mean duration 3.4 +/- 1.2 years), blood pressure (BP), hemoglobin (Hb), ECF volume (single-frequency bioelectrical impedance) and left ventricular mass index (LVMI) were determined before and after conversion. For comparison, 13 control patients (mean age 52 +/- 15 years) who remained on self-care home CHD for one year or more (mean duration 2.8 +/- 1.8 years) were studied also. Serial measurements of BP, Hb and LVMI were also obtained in this control group. RESULTS: There were no significant differences between the two cohorts with respect to age, use of antihypertensive medications, Hb, BP or LVMI at baseline. After transfer from CHD to NHD, there were significant reductions in systolic, diastolic and pulse pressure (from 145 +/- 20 to 122 +/- 13 mm Hg, P < 0.001; from 84 +/- 15 to 74 +/- 12 mm Hg, P = 0.02; from 61 +/- 12 to 49 +/- 12 mm Hg, P = 0.002, respectively) and LVMI (from 147 +/- 42 to 114 +/- 40 g/m2, P = 0.004). There was also a significant reduction in the number of prescribed antihypertensive medications (from 1.8 to 0.3, P < 0.001) and an increase in Hb in the NHD cohort. Post-dialysis ECF volume did not change. LVMI correlated with systolic blood pressure (r = 0.6, P = 0.001) during nocturnal hemodialysis. There was no relationship between changes in LVMI and changes in BP or Hb. In contrast, there were no changes in BP, Hb or LVMI in the CHD cohort over the same time period. CONCLUSIONS: Reductions in BP with NHD are accompanied by regression of LVH.     

慢性肾脏病患者血压昼夜节律异常的研究

目的 观察慢性肾脏病(CKD)患者24 h血压动态变化，探讨昼夜节律异常与肾功能损害的关系。方法 随机选择本院肾脏科CKD患者236例，高血压科原发性高血压住院患者43例。病例分组:正常对照组(NC)14例；原发性高血压组(EHC)43例；CKD血压正常组(NCKD)130例；CKD伴血压升高组(HCKD)106例。动态血压监测(ABPM)采用携带式的动态血压检测仪，ABP Report Mangement System Version 1.03.03进行数据分析。夜间血压下降率:(白昼平均值-夜间平均值)/白昼平均值，下降率≥10%，称勺型血压；<10%，称非勺型血压。结果 在血压正常的患者中，NCKD组的平均夜间收缩压和舒张压数值均高于NC组[(111.2±10.8)比 (91.6±7.5)，(68.7±9.5) 比 (56.2±4.6)mm Hg，P < 0.05]；而日间收缩压和舒张压无明显差异。在高血压患者中，HCKD组患者夜间收缩压和舒张压数值均高于EHC组[(141.9±16.5) 比(118.6±16.4)， (84.5±10.6)比(73.0±11.1)mm Hg， P < 0.05]。CKD患者无论血压正常或升高，其心率均较其对照组明显加快，尤其是夜间心率无明显下降。NCKD组、HCKD组与NC组、EHC组相比，夜间收缩压和舒张压下降数值较小，尤其是CKD伴血压升高组，呈典型的非勺型血压模式。NC组血压节律消失者占7.14%，EHC组为37.2%，NCKD组为70.0%，HCKD组为81.6%。结论 CKD患者无论血压正常或升高，夜间收缩压和舒张压下降减少或消失，呈典型的非勺型血压；血压昼夜节律异常率明显高于原发性高血压患者。在积极降低血压值的同时，还需降低血压负荷和调整血压昼夜节律，以延缓肾功能恶化。     

Regression of left ventricular hypertrophy after partial correction of anemia with erythropoietin in patients on hemodialysis: a prospective study.

Myocardial effects of recombinant human erythropoietin (rhEPO) treatment were prospectively investigated in 15 hemodialysis (HD) patients with severe anemia (hematocrit [Ht] 19.7 +/- 2.5%). Echocardiographic studies were performed after a midweek HD session just before and after a year of rhEPO. At the end of the study period, Ht had improved to 32.2 +/- 3.5% and cardiac index significantly decreased (5.48 +/- 1.54 vs 3.97 +/- 0.94 l/min/m2, p less than 0.001). Left ventricular mass index (LVMi) decreased with rhEPO (210.7 +/- 48.3 vs 139 +/- 50 g/m2, p less than 0.05). This decrease was concomitant with a decrease of LV end-diastolic diameter (4.89 +/- 0.44 vs 4.57 +/- 0.64 cm, p less than 0.05), interventricular septum thickness (IVST, 1.42 +/- 0.33 vs 1.07 +/- 0.13 cm, p less than 0.01) and LV posterior wall thickness (LVPWT, 1.28 +/- 0.21 vs 1.01 +/- 0.11 cm, p less than 0.01). Eight patients were hypertensive well controlled with hypotensive drugs (group I) and 7 normotensive (group II). LVMi was higher in group I than in group II before rhEPO (235.2 +/- 40 vs 182.7 +/- 43.1 g/m2, p less than 0.05) and significantly decreased after rhEPO in both groups (28.5% and 41.4% respectively). LVMi remained higher in group I than in group II at the end of the study (168.5 +/- 0.9 vs 106.7 +/- 24 g/m2, p less than 0.025). A moderately elevated IVST/LVPWT was reduced with a year of rhEPO (1.14 +/- 0.40 vs 1.05 +/- 0.15, p less than 0.05), disclosing correction of asymmetric septal hypertrophy. We conclude that left ventricular hypertrophy (LVH) regression is obtained after partial correction of anemia with rhEPO. Previous hypertension with current need of antihypertensive treatment has also a significant effect in the development of LVH. Whether this regression would improve outcome in HD patients remains to be established.     

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.     

An association between inflammatory state and left ventricular hypertrophy in hemodialysis patients

This study was performed to investigate the potential relationship between left ventricular hypertrophy (LVH) and proinflammatory cytokines in hemodialysis (HD) patients and the effect of HD on cytokine production. Serum interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) measurements and echocardiographic studies were performed in 35 stable HD patients. A variety of probable risk factors for LVH including age, HD duration, blood pressure (BP), body mass index, lipid profile, hemoglobin, albumin, parathormone and homocysteine levels were also investigated. Additionally, the effect of HD procedure on cytokine levels was evaluated. Predialysis serum levels of IL-1beta, IL-6, TNF-alpha, and homocysteine in HD patients were compared with 12 healthy subjects. Left ventricular hypertrophy was demonstrated in 20 (57%) of HD patients by echocardiography. Left ventricular mass index (LVMI) was correlated positively with systolic BP (r=0.556, p=0.001), diastolic BP (r=0.474, p=0.004), and serum levels of TNF-alpha (r=0.446, p=0.009). Multiple regression analysis showed that systolic BP and TNF-alpha levels were significant independent predictors of LVH. No relationship was observed between LVH and other parameters. The mean predialysis serum level of IL-6 was significantly higher in HD patients compared to healthy controls (15.7 +/- 8.7 vs. 7.3 +/- 0.7 pg/ mL, p=0.001). Predialysis serum levels of TNF-alpha in HD patients were higher when compared to healthy subjects, but the difference was not statistically significant (8.3 +/- 3 vs. 7 +/- 1.45 pg/mL, respectively, p>0.05). However, serum levels of IL-6 and TNF-alpha significantly elevated after HD, when compared to predialysis levels (from 15.7 +/- 8.7 to 17.8 +/- 9.5 pg/mL, p=0.001 and from 8.3 +/- 3.0 to 9.9 +/- 3.5 pg/mL p=0.004, respectively). As a conclusion, in addition to BP, proinflammatory cytokines, TNF-alpha in particular, seem to be associated with LVH in ESRD patients.     

Ambulatory blood pressure and left ventricular mass in normotensive patients with autosomal dominant polycystic kidney disease

Higher left ventricular mass (LVM) has been found in early stages of autosomal dominant polycystic kidney disease (ADPKD). The mechanisms involved in the increase of LVM are unknown. To investigate whether LVM in ADPKD may be influenced by abnormal diurnal BP variations, the 24-h ambulatory BP profile was analyzed in a group of young normotensive ADPKD patients. Ambulatory BP monitoring and two-dimensional echocardiography were performed in 26 young normotensive ADPKD with normal renal function and in 26 healthy control subjects. LVM index was higher in ADPKD patients than in controls (90.8+/-19.6 g/m2 versus 73.9+/-16.1 g/m2, P = 0.001). Average 24-h and daytime systolic, diastolic, and mean BP were similar in both groups. Nighttime diastolic and mean BP, but not systolic BP, were greater in ADPKD patients. The average and percent nocturnal decrease of systolic BP was lower in ADPKD patients than in control subjects (10.0 mm Hg [-3 to 24] versus 15.5 mm Hg [-4 to 31], P = 0.009, and 9.0% [-2 to 22] versus 14.2% [-2 to 25], P = 0.016, respectively). On the basis of their profile BP patterns, 54% of ADPKD subjects and 31% of controls were classified as nondippers (P = 0.092). There were no differences between dippers and nondippers in left ventricular wall thickness, chamber dimensions, and mass indexes. In ADPKD patients, simple regression analysis showed that LVM index was correlated with 24-h, daytime, and nighttime systolic BP. On multiple regression analysis, the 24-h systolic BP was the only variable linked to LVM index. It is concluded that young normotensive ADPKD patients have higher LVM that is closely related to the ambulatory systolic BP. The nocturnal fall in BP is attenuated in these patients, although it is not associated with the higher LVH that they present.     

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.     

Ambulatory blood pressure and endothelial dysfunction in patients with autosomal dominant polycystic kidney disease

Cardiovascular problems are a major cause of morbidity and mortality in patients with autosomal dominant polycystic kidney disease (ADPKD). Endothelial dysfunction (ED), which is an early manifestation of vascular injury, has been shown in patients with ADPKD. However, the association between ambulatory blood pressure and ED has not been investigated in these patients. Forty-one patients with ADPKD having well-preserved renal function were included in the study. Ambulatory blood pressure monitoring was performed in all patients. Patients were divided into dipper and non-dipper groups. Endothelial function of the brachial artery was evaluated by using high-resolution vascular ultrasound. Endothelial-dependent dilatation was expressed as the percentage change in the brachial artery diameter from baseline to reactive hyperemia. The mean 24-hour systolic blood pressure was similar in both groups (125.5 +/- 10.7 mmHg in dippers and 121.2 +/- 14.3 in non-dippers, p > 0.05). There was also no significant difference between the mean 24-hour diastolic blood pressures in both groups (82.3 +/- 9.6 mmHg in dippers and 77.1 +/- 8.6 mmHg in non-dippers, p > 0.05). The nocturnal fall rate in systolic blood pressure was 11.1 +/- 1.2% in dippers and 0.98 +/- 0.9% in non-dippers (p = 0.001). The nocturnal fall rate in diastolic blood pressure was 14.0 +/- 0.9% in dippers and 3.8 +/- 0.8% in non-dippers (p = 0.001). Endothelial-dependent dilatation was significantly higher in dippers compared to non-dippers (6.22 +/- 4.14% versus 3.57 +/- 2.52%, p = 0.025). Non-dipper patients with ADPKD show significant ED, which has an important impact on cardiovascular morbidity and mortality.     

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.     

IgA肾病患者血压节律及其与临床病理指标的关系

目的 探讨IgA肾病患者血压昼夜节律与临床病理指标的关系.方法 采用横断面调查研究.选择2009年3月至8月在IgA肾病数据库登记的原发性IgA肾病患者,收集临床病理资料,并通过动态血压监测IgA肾病患者血压昼夜节律情况.用(日间血压平均值-夜间血压平均值)/日间血压平均值判断血压昼夜节律状况.比较血压节律正常组及异常组的临床病理指标.结果 共93例患者完成动态血压监测并纳入分析.其中68例(73％)血压节律消失,在慢性肾脏病(CKD)1期、2期及3期以上组血压节律消失的比例分别70％、70％及81％,3组间差异无统计学意义(P=0.587).非勺型血压在血压正常组与高血压组比例分别为69％和77％(P=0.373).血压节律消失与年龄、性别、血压、蛋白尿、肾功能以及肾脏病理损伤程度无相关.在随访时间超过12个月的54例中,非勺型血压组eGFR下降速率虽快于勺型血压组,但差异无统计学意义(P=0.329)；在其中29例并发高血压患者中,非勺型血压组eGFR下降速率快于勺型血压组,且差异有统计学意义[(-6.79±11.58)比(-0.34±1.74)ml·min-1·(1.73 m2)-1·年-1,P=0.019].结论 IgA肾病早期即可出现明显的血压节律消失.IgA肾病伴高血压患者的血压节律消失可能是影响肾功能进展的危险因素.     

Inadequate diagnosis and therapy of arterial hypertension as causes of left ventricular hypertrophy in uremic dialysis patients

BACKGROUND: Left ventricular hypertrophy (LVH) is highly prevalent in the dialyzed population, possibly because of inadequate diagnosis and therapy of arterial hypertension. The purpose of this study was to ascertain the adequacy of our approach in correctly identifying and treating arterial hypertension in our dialysis center. METHODS: Fifty-five dialyzed uremics were studied by continuous ambulatory blood pressure (BP) monitoring, which started before a single hemodialysis (HD) session, continued for 24 hours after HD ended, and was repeated for 15 minutes before the beginning of the next HD. Clinical pre-HD and post-HD routine BP measurements taken the month preceding BP monitoring were retrieved, and echocardiography was performed. RESULTS: LVH was present in 46 out of 55 patients, and clinical pre-HD arterial hypertension was present in 36 out of 55. There were discrepancies between clinical and monitored BPs, mostly concerning diastolic pre-HD BP since BP readings were lower than monitored BP records (P < 0.0002). Although both clinical and monitored BPs bore strong direct correlations with the left ventricular mass (LVM), the closest correlations were those for monitored BP. Four groups of patients were identified by BP monitoring: group A (N = 14), with persistently normal BP, and group D (N = 13), with persistently supranormal BP levels. There were also two other groups (group B, N = 19; and group C, N = 9), whose BP values were high before HD, normalized after HD, and then increased again either soon after HD (group C) or later on following HD (group B). Monthly averaged clinical pre-HD mean BP values differed significantly among the four groups [91 +/- 10 (SD) mm Hg in group A, 101 +/- 7 in group B, 106 +/- 6 in group C, and 106 +/- 7 in group D; P < 0.0001, analysis of variance], as did their corresponding LVMs [132 +/- 27 g/m2 body surface area (BSA), 156 +/- 26, 201 +/- 51, and 200 +/- 36; P < 0.0001]. There were also differences in dialytic age, which was significantly longer in group A patients (109 +/- 54 months), who also tended to have higher, although not significantly higher, Kt/V(urea) values. No differences, however, were detected among the groups as far as type, dosages, and number of antihypertensive drugs given to each individual patient. CONCLUSIONS: The high prevalence of LVH in the dialysis population might be the result of inadequate diagnosis and therapy of arterial hypertension. Arterial hypertension, in fact, was insufficiently treated in our dialysis center, since patients with varying degrees of severity of both arterial hypertension and LVH were kept on antihypertensive therapy of similar strength. Undertreatment may have resulted from not having recognized and/or from having underestimated the severity of arterial hypertension since some clinical BPs were measured incorrectly. Reluctance to use more aggressive antihypertensive therapy might also result from the deceptive feeling of "normalized" BP that one has following volume unloading with dialysis. This causes both the BP to run out of control between dialyses and LVH to worsen.     

Left ventricular hypertrophy, treadmill tests, and 24-hour blood pressure in pediatric transplant patients.

BACKGROUND: Hypertension and left ventricular hypertrophy (LVH) are possible complications in pediatric patients after renal transplantation. METHODS: We performed left ventricular echocardiography, 24-hour ambulatory blood pressure monitoring (24-hr ABPM), and treadmill tests in 28 pediatric renal transplant patients (mean age 16.1 +/- 3.7; time since transplantation 36 +/- 23 months). Left ventricular mass (LVM) was indexed for height 2.7. RESULTS: LVH was found in 82% of the patients. Seven of these patients were normotensive by 24-hour ABPM, but five patients showed a hypertensive systolic BP response during the treadmill test. LVM/height 2.7 correlated significantly with the mean 24-hour systolic BP (P = 0.002) and with the maximal exercise systolic BP (P = 0.002). CONCLUSION: LVH is frequent in pediatric renal transplant patients. More information is needed with respect to the risk for LVH, including data from 24-hour ABPM and treadmill testing.     

Treatment of post-dialytic orthostatic hypotension with an inflatable abdominal band in hemodialysis patients

The purpose of this study was to ascertain whether abdominal compression with an inflatable abdominal band, a device we developed, improved post-dialytic orthostatic hypotension (OH) in hemodialysis (HD) patients. Twenty-five chronic HD patients with intractable post-dialytic OH were recruited. Post-HD changes in systolic blood pressure (DeltaSBP) in the supine and standing positions were compared in the patients, measured with or without the use of the band. The study showed DeltaSBP after HD without the band was significantly greater than that measured before HD (-36.1+/-18.2 vs -13.1+/-16.8 mm Hg; P<0.0001). DeltaSBP after HD with the band was reduced significantly in comparison to DeltaSBP after HD without the band (-19.4+/-21.2 vs -36.1+/-18.2 mm Hg; P<0.002). Use of the band did not cause an elevation in SBP in the supine position (149.0+/-29.6 vs 155.4+/-25.7 mm Hg); however, it did increase SBP upon standing (129.6+/-27.3 vs 117.2+/-22.6 mm Hg; P<0.05). Eight patients in whom an increase in SBP of 25 mm Hg or more was achieved with the band were classified as responders. Ejection fraction was significantly higher (76.4+/-11.1 vs 61.9+/-13.6%; P<0.02) and atrial natriuretic peptide concentration significantly lower (27.9+/-22.0 vs 68.9+/-47.5 pg/ml; P<0.02) in responders than in non-responders. We conclude that the abdominal band was effective for overcoming post-dialytic OH, without elevating supine SBP in some patients.     

Relationship between volume status and blood pressure during chronic hemodialysis.

BACKGROUND: The relationship between volume status and blood pressure (BP) in chronic hemodialysis (HD) patients remains incompletely understood. Specifically, the effect of interdialytic fluid accumulation (or intradialytic fluid removal) on BP is controversial. METHODS: We determined the association of the intradialytic decrease in body weight (as an indicator of interdialytic fluid gain) and the intradialytic decrease in plasma volume (as an indicator of postdialysis volume status) with predialysis and postdialysis BP in a cross-sectional analysis of a subset of patients (N=468) from the Hemodialysis (HEMO) Study. Fifty-five percent of patients were female, 62% were black, 43% were diabetic and 72% were prescribed antihypertensive medications. Dry weight was defined as the postdialysis body weight below which the patient developed symptomatic hypotension or muscle cramps in the absence of edema. The intradialytic decrease in plasma volume was calculated from predialysis and postdialysis total plasma protein concentrations and was expressed as a percentage of the plasma volume at the beginning of HD. RESULTS: Predialysis systolic and diastolic BP values were 153.1 +/- 24.7 (mean +/- SD) and 81.7 +/- 14.8 mm Hg, respectively; postdialysis systolic and diastolic BP values were 136.6 +/- 22.7 and 73.9 +/- 13.6 mm Hg, respectively. As a result of HD, body weight was reduced by 3.1 +/- 1.3 kg and plasma volume was contracted by 10.1 +/- 9.5%. Multiple linear regression analyses showed that each kg reduction in body weight during HD was associated with a 2.95 mm Hg (P=0.004) and a 1.65 mm Hg (P=NS) higher predialysis and postdialysis systolic BP, respectively. In contrast, each 5% greater contraction of plasma volume during HD was associated with a 1.50 mm Hg (P=0.026) and a 2.56 mm Hg (P < 0.001) lower predialysis and postdialysis systolic BP, respectively. The effects of intradialytic decreases in body weight and plasma volume were greater on systolic BP than on diastolic BP. CONCLUSIONS: HD treatment generally reduces BP, and these reductions in BP are associated with intradialytic decreases in both body weight and plasma volume. The absolute predialysis and postdialysis BP levels are influenced differently by acute intradialytic decreases in body weight and acute intradialytic decreases in plasma volume; these parameters provide different information regarding volume status and may be dissociated from each other. Therefore, evaluation of volume status in chronic HD patients requires, at minimum, assessments of both interdialytic fluid accumulation (or the intradialytic decrease in body weight) and postdialysis volume overload.