Comparison of biochemical, haematological and volume parameters in two treatment schedules of nocturnal home haemodialysis

BACKGROUND: The biochemical, haemodynamic, clinical and nutritional benefits of nocturnal home haemodialysis (NHHD) compared with 4 h, three times per week conventional haemodialysis are well known and accrue by increasing dialysis time and frequency either for 8 h alternate night per week (NHHD3.5) or for 8 h six nights per week (NHHD6). However, there are little data comparing NHHD3.5 with NHHD6. METHOD AND RESULTS: Thirteen patients on NHHD6 were compared with 21 patients on NHHD3.5, all with similar demographic profiles. Pre- and post-dialysis phosphate (PO4) control was ideal between the groups. However, all NHHD6 needed PO4 supplementation compared with 4/21 (19%) NHHD3.5. In the present study, 8/21 (38%) NHHD3.5 needed PO4 binders whereas none was required with NHHD6. The pre-haemoglobin (Hb) 122.8 g/L (NHHD6) versus 124.9 g/L (NHHD3.5) and the pre-albumin 38.31 g/L (NHHD6) versus 37.71 g/L (NHHD3.5) were not significantly different. NHHD6 had significantly lower pre-blood urea and creatinine (10.16 vs 19.54 mmol/L and 437.0 vs 812.3 micromol/L, respectively). Less interdialytic urea and creatinine fluctuation were also noted in NHHD6. Of major significance was the significantly lower ultra filtration rate and intradialytic weight gains (mean +/- SEM) of NHHD6 (249 +/- 76 mL/h and 2.0 +/- 0.65 kg) versus NHHD3.5 (425 +/- 168 mL/h and 2.9 +/- 1.2 kg). CONCLUSION: The authors conclude that NHHD6 offers the optimum biochemical, volume and clinical outcome, but NHHD3.5 has additional appeal to providers seeking home-based therapy cost advantages and consumable expenditure control. A flexible dialysis programme should offer all the time and frequency options of NHHD but in particular, should support NHHD at a frequency sympathetic to the clinical rehabilitation and lifestyle aspirations of individual patients.     

Short-term effects of nocturnal haemodialysis on carnitine metabolism.

BACKGROUND: Functional carnitine deficiency [as indicated by an abnormal acyl-carnitine/free-carnitine (AC:FC) ratio] is commonly seen in patients with end-stage renal disease (ESRD), resulting in significant clinical detriments including anaemia, cardiomyopathy and muscle weakness. Nocturnal haemodialysis (NHD) (5-6 sessions per week, 8 h per treatment) has been reported to reverse several surrogate markers of uraemia. Conversely, as a consequence of increased dialysis dose, NHD may have the potential to aggravate plasma nutrient deficiencies. Our objective was to determine the effects of NHD on plasma free-carnitine levels and carnitine metabolism. METHODS: We conducted an observational cohort study with a before and after design. Nine ESRD patients (age: 47 +/- 3; mean +/- SEM) were studied. Routine biochemical, haemodynamic and carnitine metabolic products were analysed at baseline while on conventional haemodialysis and 2 months post-conversion to NHD. Free-carnitine and total-carnitine levels were generated by colorimetric assays. The difference between total- and free-carnitine concentrations was estimated to be the acyl-carnitine level. Paired t-test was used to ascertain statistical significance. RESULTS: After conversion to NHD, there was a significant increase in urea clearance in all patients. Plasma free-carnitine levels fell from 26.54 +/- 2.99 to 15.6 +/- 2.34 micromol/l (P < 000.1). A similar reduction in plasma acyl-carnitine levels was observed (from 13.22 +/- 1.34 to 6.24 +/- 1.20 micromol/l (P < 0.001)). The AC:FC ratio improved from 0.51 +/- 0.03 to 0.39 +/- 0.03 (P < 0.005) (Normal < 0.25). CONCLUSION: NHD is associated with an improvement in AC:FC ratio. Further research is needed to examine the longitudinal clinical impact of this metabolic correction and to examine whether this effect is sustained.     

One year experience of nocturnal home haemodialysis with an alternate night schedule in Hong Kong

Aim: Nocturnal home haemodialysis (NHHD) was started in Hong Kong in 2006. The experience of 1 year of NHHD with an alternate night schedule in two local centres is reported. Methods: The clinical parameters of 14 patients who had completed 1 year of NHHD were retrospectively analyzed. All patients were receiving an alternate night schedule (3.5 sessions/week) for 6–8 h/session. Results: After 1 year of NHHD, haemoglobin levels increased from 9.6 ± 1.6 g/dL before NHHD to 11.4 ± 2.2 g/dL (P < 0.05) despite a reduction in erythropoietin dose requirement from 120.6 ± 44.3 to 59.4 ± 74.6 U/kg/week (P < 0.05). Four patients (29%) were able to stop taking erythropoietin after NHHD. Serum phosphate levels reduced from 2.33 ± 0.41 to 1.59 ± 0.29 mmol/L (P < 0.01) and calcium phosphate product decreased from 5.29 ± 0.96 to 3.74 ± 0.90 mmol²/L² (P < 0.01). Phosphate binder dose was greatly reduced and eight patients (67%) were able to stop taking phosphate binders. The number of antihypertensive medications tended to reduced from 2.5 ± 1.3 to 1.6 ± 1.5 (P = 0.067) with four patients (29%) able to stop antihypertensives. Left ventricular mass index decreased from 186 ± 62 to 168 ± 60 g/m² (P = 0.463) although this was not statistically significant. Weekly spKt/V during conventional haemodialysis was 3.63 ± 0.95 while that during NHHD was three times higher at 11.09 ± 6.44 (P < 0.01). The quality of life indexes also showed improvement. Conclusion: This 1 year experience of alternate night NHHD demonstrates benefits in terms of anaemia control, erythropoietin requirement, serum phosphate and calcium phosphate product reduction, blood pressure control, haemodialysis adequacy and quality of life. NHHD with an alternate night schedule is a promising dialytic therapy for patients receiving chronic haemodialysis in this locality.     

Relationships between blood pressure variability and left ventricular parameters in haemodialysis and renal transplant patients

SUMMARY: Blood pressure (BP) elevation and left ventricular hypertrophy (LVH) are important factors in the high cardiovascular mortality on the renal replacement programme. the relationship between these, predictable in essential hypertension, is less well defined in uraemia. We wished to examine the contribution of abnormal blood pressure variability (BPV) to the cardiovascular changes seen in uraemia and after renal transplantation. Twenty-four hour ambulatory blood pressure monitoring (ABPM), and simultaneous echocardiography, on a cohort of 35 long-term, long-hours haemodialysis survivors and 28 patients with stable renal transplants was undertaken. We also retrospectively compiled biochemical and clinical data. There were strong relationships between both diurnal and standard deviation measures of BPV and left ventricular cavity size and function: per cent fall in awake to asleep diastolic BP with fractional shortening index (FSI), r =0.28, P =0.039; with left ventricular mass index (LVMI), r =−0.35, P =0.011. This study suggests that reduced diurnal and short-term BP variability is cross-sectionally associated with a dilated, heavier left ventricle (LV) with worse systolic function. Thus, BPV may independently contribute to the abnormal LV structure and function commonly seen in uraemia.     

Relationships between blood pressure variability and left ventricular parameters in haemodialysis and renal transplant patients

Blood pressure (BP) elevation and left ventricular hypertrophy (LVH) are important factors in the high cardiovascular mortality on the renal replacement programme. The relationship between these, predictable in essential hypertension, is less well defined in uraemia. We wished to examine the contribution of abnormal blood pressure variability (BPV) to the cardiovascular changes seen in uraemia and after renal transplantation. Twenty-four hour ambulatory blood pressure monitoring (ABPM), and simultaneous echocardiography, on a cohort of 35 long-term, long-hours haemodialysis survivors and 28 patients with stable renal transplants was undertaken. We also retrospectively compiled biochemical and clinical data. There were strong relationships between both diurnal and standard deviation measures of BPV and left ventricular cavity size and function: per cent fall in awake to asleep diastolic BP with fractional shortening index (FSI), r =0.28, P =0.039; with left ventricular mass index (LVMI), r =−0.35, P =0.011. This study suggests that reduced diurnal and short-term BP variability is cross-sectionally associated with a dilated, heavier left ventricle (LV) with worse systolic function. Thus, BPV may independently contribute to the abnormal LV structure and function commonly seen in uraemia.     

Comparison of peritoneal dialysis and haemodialysis after renal transplant failure

Background. A growing number of patients are returning to dialysisafter renal transplant failure. The aim of this study is todetermine whether peritoneal dialysis (PD) is a safe and goodtreatment option for these patients. Methods. All patients returning to PD or haemodialysis (HD)after renal transplant failure before 1 October 2002 at theUniversity Hospital Gasthuisberg, Leuven, Belgium, were evaluated.Data were collected until death, retransplantation (reTx), transferto HD or PD or until 1 January 2003. Results. Twenty-one patients starting PD (PDpostTx-group) and39 patients starting HD (HDpostTx-group) after renal transplantfailure were included in the study. There were no significantdifferences in age, sex, serum albumin- and CRP-levels at baseline.The total time on renal replacement therapy at transplant failureand time to transplant failure did not differ between the twogroups either. Furthermore, the baseline comorbidity was similarin both groups. During follow-up, the outcome did not differsignificantly between the two groups. However, there was a tendencytowards higher patient survival and reTx tended to be more frequentin the PDpostTx-group. Moreover, patients in the HDpostTx-grouptended to accrue more new comorbidity. The incidence of peritonitisand the evolution of dialysis adequacy (renal and peritonealKt/V and creatinine clearances) with time in the PDpostTx-groupwas similar to that seen in our centre's PD patients who hadnever undergone transplantation before. Conclusions. This study suggests that the outcome in patientsstarting PD after renal transplant failure is at least as goodas the outcome in those starting HD. Although these observationalfindings warrant further confirmation, PD therefore can be regardedas a safe and good treatment option for patients returning todialysis after renal transplant failure.     

beta(2)-microglobulin kinetics in nocturnal haemodialysis.

BACKGROUND: beta(2)-Microglobulin (beta(2)m) is a major component of dialysis-related amyloidosis. The available therapeutic options do not permit normalization of the serum beta(2)m level. In a cross-over trial, we studied the kinetics of beta(2)m during two different dialytic techniques. METHODS: Ten stable, anuric end-stage renal disease patients were studied during two consecutive weeks of three conventional (CHD) and six nocturnal haemodialysis (NHD) sessions. CHD was performed for 4 h three times weekly using a polysulfone dialyser (F80, surface area of 1.8 m(2)) with a mean blood and dialysate flow rate of 401+/-91.6 and 514+/-10.9 ml/min, respectively. The NHD was done with a smaller dialyser (F40, surface area of 0.7 m(2)) and lower blood (281+/-17 ml/min) and dialysate flow rates (99+/-1.2 ml/min) for 8 h, six nights a week. RESULTS: Weekly removal of urea (51.6+/-24.6 vs 43.1+/-20.5 g) and creatinine (8501+/-5204 vs 6319+/-4134 mg) were comparable with the two modalities of dialysis but the mass of beta(2)m removed was significantly higher with NHD (127+/-48 vs 585+/-309 mg, P<0.001), with a percentage reduction in serum level of 20.5+/-5.8 vs 38.8+/-7. 1% (P<0.0001) and a Kt/V(beta2m) of 0.21+/-0.09 vs 0.56+/-0.17 (P<0. 0006). The mean post-dialysis beta(2)m (20.8+/-6.3 vs 14.0+/-3.8 mg/dl, P=0.02), Tac(beta2m) (26.2+/-5.2 vs 19.8+/-3.8 mg/dl, P=0.02) and pre-dialysis beta(2)m (beta(2)m(pre)) at the end of 1 week of therapy (24.4+/-7.6 vs 19.0+/-3.4 mg/dl, P=0.02) were lower with NHD. Long-term follow-up data were available in 13 and seven patients at the end of 1 and 2 years, respectively. Serum beta(2)m(pre) levels progressively declined from 27.2+/-11.7 mg/dl at initiation of NHD to 13.7+/-4.4 mg/dl by 9 months, and they remained stable thereafter. CONCLUSIONS: NHD provides a much higher clearance of beta(2)m than CHD, leading to a long-term decrease in the pre-dialysis concentration of beta(2)m.     

The natural history of coronary calcification progression in a cohort of nocturnal haemodialysis patients.

BACKGROUND: End-stage renal disease (ESRD) is associated with a markedly increased cardiac calcification burden, as reflected by computed tomography scans of the heart. Nocturnal haemodialysis (NHD) is a novel form of renal replacement therapy which has multiple physiologic effects that may affect vascular calcification, including improvements in phosphate and uraemia control. The objective of the present study is the determination of the natural history of coronary calcification progression in patients converted to NHD, and the examination of the relationships between calcification risk factors and calcification progression in these patients. METHODS: Thirty-eight ESRD patients were converted to NHD, and included in our observational cohort study. Coronary artery calcification scores (CACS) were documented at baseline and post-conversion (mean interscan duration 16+/-1 months). Other variables of interest included age, dialysis vintage, Framingham risk profile, phosphate binder and vitamin D usage, and plasma levels of calcium, phosphate and parathyroid hormone. RESULTS: Our cohort was stratified according to baseline calcification burden (minimal calcification: CACS < or = 10 vs significant calcification: CACS > 10). Twenty-four patients had baseline CACS < or = 10. These patients demonstrated no change in coronary calcification after 1 year of NHD (from 0.7+/-0.5 to 6+/-3, P = 0.1). Fourteen patients had higher initial CACS at baseline (1874+/-696), and demonstrated a non-significant 9% increase over 1 year to 2038+/-740 (P = 0.1). Plasma phosphate and calcium x phosphate product were significantly reduced, as were calcium-based phosphate binder and antihypertensive usage. CONCLUSIONS: Our study is the first to document CACS progression in a cohort of NHD patients. Further analysis of the effect of NHD on the physiology of cardiovascular calcification is required.     

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.     

Calcium and phosphate balance in adolescents on home nocturnal haemodialysis

Studies in adults show superior serum phosphate and parathyroid hormone (PTH) control on slow nocturnal haemodialysis (NHD) compared with conventional haemodialysis. We studied the progress of four children aged 12, 13, 14 and 16 years after they had been initiated on NHD. The follow-up period ranged from 6 months to 20 months. Biochemical indices of bone metabolism were collected prospectively. All four children were initially dialysed against a 1.5 mmol/l calcium bath. In two patients, owing to biochemical hypocalcaemic episodes, the dialysate calcium concentration was increased to 1.75 mmol/l. One patient became hypercalcaemic and received calcitonin for bone pain secondary to osteoporosis and was dialysed against a 1.0 mmol/l calcium bath. Including an evaluation of dietary intake, all four patients had a net positive calcium balance, ranging from 5.1 mmol/m² body surface area (BSA) per day to 24.3 mmol/m² BSA per day. A significant reduction in the pre-dialysis phosphate level was observed in all four patients, such that none required dietary restrictions or phosphate binders, and dialysate phosphate supplements of 0.8–2.03 mmol/l were employed to prevent hypophosphataemia. The (Ca×PO4) dropped below 4.4 mmol² l⁻² in all four patients. Concurrently, significant reductions in intact PTH levels were seen in all four patients, but the level dropped to below normal range in two. In our cohort of patients, NHD rapidly lowered plasma phosphate and PTH levels, and additional dialysate phosphate and possibly calcium may be necessary to prevent bone demineralisation due to chronic losses and to prevent oversuppression of PTH.     

Pattern of renal osteodystrophy in haemodialysis patients in Saudi Arabia

In order to know the pattern of renal osteodystrophy in haemodialysispatients in Saudi Arabia we conducted a multicentre study involving209 patients. The mean age of the patients was 39.4±14(18–70) years, 128 were males and 81 females. All patientswere on acetate dialysate and their mean duration on dialysiswas 3.5 ± 1.5 years. The major symptom was bone and joint pain (25.8%). The meanserum calcium was 2.1 ±0.26 mmol/l, phosphorus 2.0 ±0.36mmol/l, alkaline phosphatase 19.7± 14.6 u/l and parathyroidhormone level was 8.9 ± 3.9mg/ml. The mean serum aluminium(AL) level was 25.4±17.7 µg/l, while that of 1,25vitamin D3 was 8.1±4.2ng/l and of fluoride was 92.2 ±31.4 µg/l. The major radiological finding was osteosclerosis(70%). Dual-photon absorptiometry (DPA) showed low bone mineraldensity (LBM) in 65% of the patients. Forty-one patients had bone biopsies with AL staining of thebiopsies. Of this group, 92% had changes of hyperparathyroidismand 66% of them were pure hyperparathyroidism. Sixty percentof them had variable degrees of AL intoxication. The radiologicalskeletal survey of those patients could detect abnormalitiesin only 46% while 70% of them had abnormal bone mineral density(BMD). In conclusion, osteosclerosis is the commonest radiologicalfinding in our dialysis patients while secondary hyperparathyroidismis the main histopathological diagnosis in bone biopsy, evenin patients with normal skeletal survey. AL intoxication isa significant problem in our population. DPA is more sensitivein detecting bone abnormalities than X-radiography.     

Improvement in ejection fraction by nocturnal haemodialysis in end-stage renal failure patients with coexisting heart failure.

BACKGROUND: Congestive heart failure (CHF) is an independent risk factor for mortality in the end-stage renal disease (ESRD) population. Nocturnal haemodialysis (NHD), a novel mode of renal replacement therapy, may be more effective than conventional haemodialysis in reducing intravascular volume or in removing uraemic toxins with vasoconstrictor or myocardial depressant actions, and may, therefore, improve the left ventricular (LV) systolic function of patients with coexisting cardiac and renal failure. METHODS: To test this hypothesis, we determined, in six patients (mean age+/-SD: 49.5+/-9 years), blood pressure (BP), ejection fraction (EF: radionucleotide angiography), left ventricular mass index (LVMI: echocardiography), LV fractional shortening (FS), and extracellular fluid volume (ECFV: bioelectrical impedance): before and after a mean of 3.2+/-2.1 years following conversion from conventional dialysis (3 days/week x 4 h) to NHD (6 nights/week x 8-10 h). RESULTS: There were significant reductions in systolic and mean arterial BP (138+/-10 to 120+/-9 mmHg, P=0.04; 99+/-6 to 86+/-7 mmHg, P=0.01). There was a significant increase in EF (28+/-12 to 41+/-18%, P=0.01) and a trend to greater LV FS (20+/-10 to 38+/-17%, P=0.06). Post-dialysis ECFV was not affected by dialysis mode (18.5+/-5.1 vs 18.2+/-3.5 l, P=0.76). The number of prescribed cardiovascular medications was reduced (2.2-0.7, P=0.02). CONCLUSIONS: In ESRD patients with systolic dysfunction, NHD leads to a sustained increase of EF and a reduction in the requirement for vasoactive medications in the absence of any reduction in post-dialysis ECFV.     

Effect of renal transplantation on endothelial function in haemodialysis patients.

BACKGROUND: Haemodialysis patients (HD) have been characterized by a high incidence and prevalence of atherosclerotic cardiovascular disease. Based on the traditional cardiovascular risk factors in this population, we cannot explain this high incidence and prevalence. One of the mechanisms contributing to cardiovascular risk in HD patients may be to uraemic toxins. Cardiovascular risk factors and uraemic toxins themselves may cause endothelial dysfunction, which may play a pivotal role in the development and progression of atherosclerosis in this population. We hypothesized that elimination of uraemic toxins in response to renal transplantation (RTx) can improve endothelial function as assessed by flow-mediated dilatation of brachial artery in haemodialysis (HD) patients. METHODS: Endothelial function measured by flow-mediated dilatation of the brachial artery (FMD) and glyceryltrinitrate-induced dilatation of the brachial artery (NMD) were assessed twice, during haemodialysis treatment and after RTx in 30 chronic haemodialysis patients. All patients were characterized by absence of known atherosclerotic disease and traditional cardiovascular risk factors. We also studied age- and gender-matched 20 normotensive healthy controls. RESULTS: FMD values significantly improved after RTx (6.69+/-3.1% vs 10.50+/-3.0%, P<0.001) in HD patients. FMD of patients both during haemodialysis and after RTx was lower than in healthy controls (6.69+/-3.1%, 10.50+/-3.0% vs 14.02+/-2.3%, P<0.001 and P<0.01, respectively). There was no change in NMD values after RTx in HD patients (16.27+/-1.9% vs 16.30+/-1.8%, P>0.05). Also, NMD values in all patients were similar to healthy control values. CONCLUSIONS: There is an improvement of endothelial function as assessed by FMD of the brachial artery after RTx in HD patients. This may be attributed to the elimination of uraemic toxins by successful RTx.     

Improvement in exercise duration and capacity after conversion to nocturnal home haemodialysis.

BACKGROUND: Patients with end-stage renal disease (ESRD) have a reduced exercise capacity as assessed by peak oxygen uptake (VO2peak). Nocturnal haemodialysis (NHD) augments uraemic clearance and vascular responsiveness to nitric oxide and lowers blood pressure (BP) and peripheral resistance. METHODS: To assess the impact of NHD on exercise duration and capacity, 13 consecutive ESRD patients [age: 41 +/- 3; (mean +/- SEM)] and healthy normal subjects (n = 14) matched for age and body mass index exercised to peak effort (VO2peak) as determined by open-circuit spirometry during a graded cycle ergometer test with a ramp increase in work rate (by 17 watts/min). RESULTS: Exercise was performed before, 2 and 3-6 months after conversion from conventional haemodialysis (CHD) (3 sessions per week; 4 h per session) to NHD (5-6 sessions per week; 6-8 h per session). Exercise duration increased progressively [from 617 +/- 50 (CHD) to 634 +/- 47 (NHD 2 months) to 682 +/- 55 [NHD 3-6 months], P = 0.03) as did exercise capacity, expressed as percent of predicted (based on age, sex and body size) VO2peak, [from 66 +/- 8 (CHD) to 72 +/- 6 (NHD 2 months) to 75 +/- 6% (NHD 3-6 months), P < 0.05). CONCLUSION: Enhanced uraemia control by NHD improved both exercise duration and capacity. When coupled with augmented uraemia management, an increase in physical activity, perhaps due to more effective oxygen delivery or improved muscle metabolism, has the potential to improve the quality of life of patients with ESRD.