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The incidence of cerebrovascular events and peripheral vascular disease is higher in dialysis patients compared to the general population. Although normotensive dialysis patients have an elevated risk of stroke, hypertension remains an important risk factor for symptomatic cerebrovascular accidents. The risk of stroke increases in a linear fashion with blood pressure (BP) level. Furthermore, hypertension is also an important risk factor for silent cerebral infarction in dialysis patients. With regard to peripheral vascular disease, the association with hypertension is less clear. The spectrum of cerebrovascular accidents differs from the general population, as the relative incidence of cerebral hemorrhage to cerebral infarction is much higher. The prognosis of cerebral hemorrhage is poor and depends on the size and location of the hemorrhage. In order to prevent noncardiac complications, strict control of hypertension is of major importance in dialysis patients.

Volume and sodium excess is the predominant factor in the pathogenesis of hypertension in dialysis patients. However, except for anephric patients, the relationship between volume status, blood pressure, and hemodynamics is not straightforward, but may vary between subgroups of patients. In general, the sensitivity of blood pressure to changes in the volume/sodium status appears to be increased in patients with end-stage renal disease. The blood pressure response to changes in the sodium/volume status may be influenced by disturbances in the activity of and response to various neurohumoral mechanisms, such as the renin-angiotensin and sympathetic nervous systems, Na-K-ATP-ase inhibitors, and the nitric oxide system. Regarding these aspects, there might be a parallel with salt-sensitive (essential) hypertension. Preliminary data showed a beneficial effect of sodium removal beyond changes in the volume status. Also of interest is the fact that prolonging dialysis time may improve blood pressure control without clear changes in the fluid status. It is hypothesized that a reduction in exchangeable sodium, by increased diffusive transport of sodium, in combination with increased removal of vasopressor substances, might be partly responsible for the observed blood pressure changes during long dialysis times. In conclusion, sodium and volume overload and neurohumoral factors coincide in the pathogenesis of hypertension in dialysis patients. Nevertheless, their exact relationship has not yet been elucidated and deserves further study.

Because of changes in legislation, dialysis may now be performed in all hospitals in The Netherlands, which could affect the quality of the therapy. Therefore a system of quality management in health care, and especially in dialysis, was developed. In this article the implementation and evaluation of such a system is described.

A reliable assessment of nutritional state in peritoneal dialysis (PD) patients is of great importance. Nevertheless, techniques used to assess body composition in patients on PD may be affected by abnormalities in fluid status. The primary aim of the present study was to compare different techniques used to evaluate body composition and to assess the influence of fluid status on the assessment of body composition. The secondary aim was to assess the relevance of handgrip muscle strength in the nutritional evaluation of the patient.In 40 PD patients, dual-energy x-ray absorptiometry (DEXA), multifrequency bioimpedance analysis (MF-BIA), and anthropometry were compared with respect to the evaluation of body composition [fat mass and lean body mass (LBM; by DEXA), and fat-free mass (FFM; by MF-BIA, anthropometry]. The influence of fluid status on the measurement of LBM/FFM by the various techniques was assessed by their relation to left ventricular end-diastolic diameter (LVEDD), assessed by echocardiography, and by estimating the ratio between extracellular water (ECW) and total body water (TBW), assessed by bromide and deuterium dilution, with LBM (DEXA). The relevance of handgrip muscle strength as a nutritional parameter was assessed by its relation to LBM and other nutritional parameters.Despite highly significant correlations, wide limits of agreement between the various techniques were present with respect to assessment of body composition (expressed as % body weight) and were most pronounced for anthropometry: LBM (DEXA) - FFM (MF-BIA) = 3.4% +/- 12.2%; LBM (DEXA) - FFM (anthropometry) = -5.7% +/- 7.8%; fat mass (DEXA - MF-BIA) = -4.2% +/- 7.9%; fat mass (DEXA - anthropometry) = 2.9% +/- 7.2%. The ratio between ECW and LBM (DEXA) was 0.36 +/- 0.08 L/kg (range 0.25 - 0.67 L/kg), and the ratio between TBW and LBM was 0.75 +/- 0.06 L/kg (range 0.63 - 0.86 L/kg), which shows the variability in hydration state of LBM/FFM between individual patients. LBM/FFM measured by all three techniques was significantly related to LVEDD, suggesting an important influence of hydration state on this parameter. Handgrip muscle strength was significantly related to LBM/FFM, as measured by all three techniques, but not to other nutritional parameters.Wide limits of agreement were found between various techniques used to assess body composition in PD patients. The assessment of body composition was strongly influenced by hydration state. The handgrip test is related to body composition, but not to other nutritional parameters.

Hypertension, reduced arterial distensibility, and left ventricular hypertrophy (LVH) are risk factors for mortality in hemodialysis patients. However, few studies have focused on the relation between fluid status, blood pressure (BP), and cardiovascular abnormalities in peritoneal dialysis (PD) patients. This study was designed, first, to assess, using tracer dilution techniques, fluid status in PD patients compared to a control population of stable renal transplant (RTx) patients; second, to study the relation between fluid status, BP, and arterial wall abnormalities; third, to assess the determinants of cardiac structure; and last, to compare office and ambulatory BP measurements with respect to cardiac abnormalities.Cross-sectional study.Multicenter study.41 stable PD patients with a mean Kt/V urea of 2.4 +/- 0.7, and 77 stable RTx patients.Fluid status was assessed by tracer dilution techniques: extracellular volume (ECV) with bromide dilution; total body water (TBW) with deuterium oxide; and plasma volume (PV) with dextran 70. Echocardiography was performed to assess left ventricular mass (LVM), left ventricular end diastolic diameter (LVEDD), and relative wall thickness as indicators of LVH. Echography of the common carotid artery was performed to assess arterial distensibility. Both office and 24-hour ambulatory BP measurements were performed.Fluid status, as assessed by ECV corrected for body surface area (BSA) (ECV:BSA), was significantly different between PD and RTx patients (9.4 +/- 2.6 vs 8.6 +/- 1.2 L/m2, p0.05). In 36.6% of the PD patients, ECV:BSA was above the 90th percentile of the RTx patients. Fluid status corrected for BSA, assessed by TBW (TBW:BSA), ECV (ECV:BSA), or plasma volume (PV:BSA), was significantly related to diastolic BP (DBP) (r = 0.35, r = 0.37, r = 0.53; p0.05). Arterial distensibility of the common carotid artery was related to systolic BP (SBP) (r = -0.36, p0.05). ECV was significantly related to LVEDD (r = 0.41, p0.05) as a marker of eccentric LVH, whereas arterial distensibility was related to relative wall thickness (r = -0.53, p0.001) as a marker of concentric LVH. An abnormal day-night BP rhythm, which was not related to fluid status, was observed in 68.4% of patients. Ambulatory DBP and SBP but not office DBP and SBP were related to LVM (r = 0.43, r = 0.46; p0.01).A large proportion of PD patients whose treatment prescriptions are in accordance with the Dialysis Outcomes Quality Initiative guidelines were found to be overhydrated compared with a population of stable RTx patients. Fluid status was significantly related to DBP and eccentric LVH, whereas arterial distensibility of the common carotid artery was significantly related to SBP and concentric LVH. In contrast to ambulatory BP, office BP was not related to LVM.