Use of Covered Stents in Cannulation Sites as a Last Option to Salvage Failing Vascular Access.

PURPOSE: Controversy exists regarding the treatment of recurrent stenosis in vascular access at cannulation sites with a covered stent as repeated cannulation may damage the stent. The purpose of this study was to review covered stent placement at cannulation sites to salvage failing vascular access. MATERIALS AND METHODS: A total of 11 patients were included for the purpose of this study. Eight patients (72.7%) received a covered stent due to recurrent stenosis, 2 (18.2%) due to an acute occlusion, and in 1 case (9.1%), the covered stent was used to repair a damaged polytetrafluoroethylene arteriovenous graft (PTFE AVG). RESULTS: Primary patency after stent placement was 40.9% at 6 months, primary-assisted patency was 79.5% at 12 months, and secondary patency was 80% at 24 months. No significant problems were observed during the dialysis sessions after stent placement. The intervention rate per patient-year was not significantly different before or after covered stent placement, at 3.8 (IQR=9.5) interventions per year versus 2.5 (IQR=3.0) interventions per year (p=0.280). CONCLUSION: In conclusion, treating failing vascular access with problems at cannulation sites with covered stents can be considered. CLINICAL IMPACT: Treating vascular access stenosis at cannulation sites with covered stents can successfully prolong vascular access life.

Impact of Polypharmacy on Health-Related Quality of Life in Dialysis Patients.

INTRODUCTION: Dialysis patients are often prescribed a large number of medications to improve metabolic control and manage coexisting comorbidities. However, some studies suggest that a large number of medications could also detrimentally affect patients' health-related quality of life (HRQoL). Therefore, this study aims to provide insight in the association between the number of types of medications and HRQoL in dialysis patients. METHODS: A multicentre cohort study was conducted among dialysis patients from Dutch dialysis centres 3 months after initiation of dialysis as part of the ongoing prospective DOMESTICO study. The number of types of medications, defined as the number of concomitantly prescribed types of drugs, was obtained from electronic patient records. Primary outcome was HRQoL measured with the Physical Component Summary (PCS) score and Mental Component Summary (MCS) score (range 0-100) of the Short Form 12. Secondary outcomes were number of symptoms (range 0-30) measured with the Dialysis Symptoms Index and self-rated health (range 0-100) measured with the EuroQol-5D-5L. Data were analysed using linear regression and adjusted for possible confounders, including comorbidity. Analyses for MCS and number of symptoms were performed after categorizing patients in tertiles according to their number of medications because assumptions of linearity were violated for these outcomes. RESULTS: A total of 162 patients were included. Mean age of patients was 58 ± 17 years, 35% were female, and 80% underwent haemodialysis. The mean number of medications was 12.2 ± 4.5. Mean PCS and MCS were 36.6 ± 10.2 and 46.8 ± 10.0, respectively. The mean number of symptoms was 12.3 ± 6.9 and the mean self-rated health 60.1 ± 20.6. In adjusted analyses, PCS was 0.6 point lower for each additional medication (95% confidence interval [95% CI]: -0.9 to -0.2; p = 0.002). MCS was 4.9 point lower (95% CI: -8.8 to -1.0; p = 0.01) and 1.0 point lower (95% CI: -5.1-3.1; p = 0.63) for the highest and middle tertiles of medications, respectively, than for the lowest tertile. Patients in the highest tertile of medications reported 4.1 more symptoms than in the lowest tertile (95% CI: 1.5-6.6; p = 0.002), but no significant difference in the number of symptoms was observed between the middle and lowest tertiles. Self-rated health was 1.5 point lower for each medication (95% CI: -2.2 to -0.7; p < 0.001). DISCUSSION/CONCLUSION: After adjustment for comorbidity and other confounders, a higher number of medications were associated with a lower PCS, MCS, and self-rated health in dialysis patients and with more symptoms.

Coronary Artery Calcification in Hemodialysis and Peritoneal Dialysis.

BACKGROUND: Vascular calcification is seen in most patients on dialysis and is strongly associated with cardiovascular mortality. Vascular calcification is promoted by phosphate, which generally reaches higher levels in hemodialysis than in peritoneal dialysis. However, whether vascular calcification develops less in peritoneal dialysis than in hemodialysis is currently unknown. Therefore, we compared coronary artery calcification (CAC), its progression, and calcification biomarkers between patients on hemodialysis and peritoneal dialysis. METHODS: We measured CAC in 134 patients who had been treated exclusively with hemodialysis (n = 94) or peritoneal dialysis (n = 40) and were transplantation candidates. In 57 of them (34 on hemodialysis and 23 on peritoneal dialysis), we also measured CAC progression annually up to 3 years and the inactive species of desphospho-uncarboxylated matrix Gla protein (dp-ucMGP), fetuin-A, osteoprotegerin. We compared CAC cross-sectionally with Tobit regression. CAC progression was compared in 2 ways: with linear mixed models as the difference in square root transformed volume score per year (ΔCAC SQRV) and with Tobit mixed models. We adjusted for potential confounders. RESULTS: In the cross-sectional cohort, CAC volume scores were 92 mm3 in hemodialysis and 492 mm3 in peritoneal dialysis (adjusted difference 436 mm3; 95% CI -47 to 919; p = 0.08). In the longitudinal cohort, peritoneal dialysis was associated with significantly more CAC progression defined as ΔCAC SQRV (adjusted difference 1.20; 95% CI 0.09 to 2.31; p = 0.03), but not with Tobit mixed models (adjusted difference in CAC score increase per year 106 mm3; 95% CI -140 to 352; p = 0.40). Peritoneal dialysis was associated with higher osteoprotegerin (adjusted p = 0.02) but not with dp-ucMGP or fetuin-A. CONCLUSIONS: Peritoneal dialysis is not associated with less CAC or CAC progression than hemodialysis, and perhaps with even more progression. This indicates that vascular calcification does not develop less in peritoneal dialysis than in hemodialysis.

Impact of the Introduction of Calcimimetics on Timing of Parathyroidectomy in Secondary and Tertiary Hyperparathyroidism.

BACKGROUND: Hyperparathyroidism (HPT), both secondary and tertiary, is common in patients with end-stage renal disease, and is associated with severe bone disorders, cardiovascular complications, and increased mortality. Since the introduction of calcimimetics in 2004, treatment of HPT has shifted from surgery to predominantly medical therapy. OBJECTIVE: The aim of this study was to evaluate the impact of this change of management on the HPT patient population before undergoing (sub-)total parathyroidectomy (PTx). METHODS: Overall, 119 patients with secondary or tertiary HPT undergoing PTx were included in a retrospective, single-center cohort. Group A, who underwent PTx before January 2005, was compared with group B, who underwent PTx after January 2005. Patient characteristics, time interval between HPT diagnosis and PTx, and postoperative complications were compared. RESULTS: Group A comprised 70 (58.8 %) patients and group B comprised 49 (41.2 %) patients. The median interval between HPT diagnosis and PTx was 27 (interquartile range [IQR] 12.5-48.0) and 49 (IQR 21.0-75.0) months for group A and B, respectively (p = 0.007). Baseline characteristics were similar among both groups. The median preoperative serum parathyroid hormone (PTH) level was 936 pg/mL (IQR 600-1273) for group A versus 1091 pg/mL (IQR 482-1373) for group B (p = 0.38). PTx resulted in a dramatic PTH reduction (less than twofold the upper limit: A, 80.0 %; B, 85.4 %), and postoperative complication rates were low in both groups (A: 7.8 %; B: 10.2 %) [p = 0.66]. CONCLUSIONS: The introduction of calcimimetics in 2004 is associated with a significant 2-year delay of surgery with continuously elevated preoperative PTH levels, while parathyroid surgery, even in a fragile population, is considered a safe and effective procedure.

Screening for elevated albuminuria and subsequently hypertension identifies subjects in which treatment may be warranted to prevent renal function decline.

Background: We investigated whether initial population screening for elevated albuminuria with subsequent screening for hypertension in case albuminuria is elevated may be of help to identify subjects at risk for accelerated decline in kidney function. Methods: We included subjects who participate in the PREVEND observational, general population-based cohort study and had two or more glomerular filtration rate (eGFR) measurements available during follow-up. Elevated albuminuria was defined as an albumin concentration ≥20 mg/L in a first morning urine sample confirmed by an albumin excretion ≥30 mg/day in two 24-h urines. Hypertension was defined as systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg or use of blood pressure-lowering drugs. eGFR was estimated with the CKD-EPI creatinine-cystatin C equation. Results: Overall, 6471 subjects were included with a median of 4 [95% confidence interval (CI) 2-5] eGFR measurements during a follow-up of 11.3 (95% CI 4.0-13.7) years. Decline in eGFR was greater in the subgroups with elevated albuminuria. This held true, not only in subjects with known hypertension (-1.84 ± 2.27 versus -1.16 ± 1.45 mL/min/1.73 m 2 per year, P < 0.05), but also in subjects with newly diagnosed hypertension (-1.59 ± 1.55 versus -1.14 ± 1.38 mL/min/1.73 m 2 per year, P < 0.05) and in subjects with normal blood pressure (-1.18 ± 1.85 versus -0.81 ± 1.02 mL/min/1.73 m 2 per year in subjects, P < 0.05). This effect was most pronounced in the population ≥55 years of age and male subjects. In addition, subjects with elevated albuminuria had higher blood pressure than subjects with normoalbuminuria, and in subjects with elevated albuminuria as yet undiagnosed hypertension was twice as prevalent as diagnosed hypertension. Conclusions: Initial screening for elevated albuminuria followed by screening for hypertension may help to detect subjects with increased risk for a steeper decline in kidney function.

An international feasibility study of home haemodialysis in older patients.

BACKGROUND: Home haemodialysis (HHD) is undergoing a significant revival. There is a global demographic shift with a rising mean age of dialysis patients. We postulated that intensive HHD may also benefit the older dialysis population. However, there is a lack of literature on the feasibility of HHD in older patients with end-stage renal disease (ESRD). The purpose of this study was to ascertain the feasibility of delivering HHD to older patients. METHODS: We conducted a multi-centre multinational retrospective cohort study of HHD patients ≥65 years of age at the time of HHD initiation; 79 patients were included. Baseline demographic data included age at start of dialysis, race and sex. Dialysis characteristics including total weekly treatment hours, need for assistance, training time, dialysis access, modality and dialysis vintage were captured, as well as cause of ESRD and medical co-morbidities. The primary outcome was time to technique failure or death. Rates of hospitalization, cardiovascular events, non-infectious vascular access events and infections were collected. RESULTS: Median age at start was 68 (interquartile range 66-71) years. An arteriovenous fistula was the predominant access, and most patients were receiving <16 h of total weekly dialysis treatment. Family or nurse assistance for dialysis was required in 54% of patients. There were 17 (22%) deaths and 20 (26%) technique failures. The cumulative time at risk was 188 years. Event-free survival at 1, 2 and 5 years was 85, 77 and 24%, respectively, and technique survival was 92, 83 and 56%, respectively. Advancing age (categorized into quartiles) was an unadjusted risk factor for death and technique failure. CONCLUSIONS: This analysis confirms feasibility of HHD in patients 65 years or older at the start of this modality and should foster further research on the potential benefits of (intensive) HHD in older ESRD patients.

Screening for albuminuria with subsequent screening for hypertension and hypercholesterolaemia identifies subjects in whom treatment is warranted to prevent cardiovascular events.

BACKGROUND: In the general population, many subjects have yet unrecognized hypertension and hypercholesterolaemia, and are thus not treated. We investigated whether population screening for elevated albuminuria can identify subjects with previously unrecognized hypertension and/or hypercholesterolaemia at high risk for cardiovascular (CV) disease. METHODS: Included were 8143 subjects (28-75 years) that participate in the PREVEND study, a general population-based, observational cohort study. Elevated albuminuria was defined as an albumin concentration ≥ 20 mg/L in a first morning urine sample confirmed by an albumin excretion ≥ 30 mg/day in two 24-h urine samples. Hypertension was defined as SBP ≥ 140 mmHg or DBP ≥ 90 mmHg, and hypercholesterolaemia as serum total cholesterol ≥ 6.2 mmol/L, or as HDL cholesterol < 0.9 mmol/L and a total/HDL cholesterol ratio of ≥ 6. Combined CV morbidity and mortality during follow-up was adopted as outcome. RESULTS: In the group with, as well as in the group without elevated albuminuria, the number of subjects with yet unrecognized hypertension and hypercholesterolaemia was at least 2-fold higher than the number of subjects known with these CV risk factors. Mean follow-up was 7.1 ± 1.5 years, during which 445 CV events occurred. The hazard ratio for CV events was significantly elevated in the subjects with, compared with those without elevated albuminuria, independent of whether they had no CV risk factor present, a CV risk factor known or a CV risk factor newly discovered. The CV event rate in those with an elevated albuminuria crossed the recommended threshold to start antihypertensive or anticholesterolaemic treatment, not only when the CV risk factor was known, but also in the subgroup with newly diagnosed CV risk factor. In subjects with a newly discovered CV risk factor without albuminuria, absolute CV risk was significantly lower. CONCLUSIONS: Screening for elevated albuminuria and subsequent screening for CV risk factors identify subjects with yet unknown CV risk factors at high risk for CV disease that are likely to benefit from early preventive treatment.

Differences in shuntflow (Qa), cardiac function and mortality between hemodialysis patients with a lower-arm fistula, an upper-arm fistula, and an arteriovenous graft.

BACKGROUND: High-flow vascular accesses may contribute to cardiovascular morbidity and mortality in hemodialysis patients. Since shuntflow (Qa) varies between vascular access types, the current study aims to investigate differences in left ventricular hypertrophy (LVH), systolic and diastolic function parameters, and all-cause mortality between patients with a lower-arm arteriovenous fistula (AVF), an upper-arm AVF, and an arteriovenous graft (AVG). METHODS: A post hoc analysis of 100 patients was performed in a single-center, prospective observational study. Echocardiography examinations were performed prior to the dialysis session. Qa measurements were performed using ultrasound dilution. Patient groups were categorized by vascular access type. Cox proportional hazards models were used to investigate the association of shunt type with all-cause mortality with adjustment for potential confounders including, amongst others, age, sex, diabetes, the duration of hemodialysis treatment, shunt vintage, and Qa. RESULTS: Patients with an upper-arm AVF had significantly (p < 0.001) higher Qa (median 1902, IQR 1223-2508 ml/min) compared to patients with a lower-arm AVF (median 891, IQR 696-1414 ml/min) and patients with an AVG (median 881, IQR 580-1157 ml/min). The proportion of patients with LVH and systolic and diastolic echocardiographic parameters did not differ significantly between groups. Survival analysis showed that an upper-arm AVF was associated with a significantly lower all-cause mortality (p = 0.04) compared to a lower-arm AVF. CONCLUSIONS: Patients with an upper-arm fistula had a higher Qa but similar systolic and diastolic cardiac function. Patients with an upper-arm fistula had a significantly lower risk of all-cause mortality compared with patients with a lower-arm fistula.

Screening for chronic kidney disease can be of help to prevent atherosclerotic end-organ damage.

Atherosclerotic damage to the kidney is one of the most prevalent causes of chronic kidney disease and ultimately kidney failure. It frequently coincides with atherosclerotic damage to the heart, the brain and the lower extremities. In fact, the severity of the damage in the various end organs runs in parallel. As damage to the kidney is easy to measure by monitoring albuminuria and eGFR, and as the early phases of kidney damage frequently precede the alarming symptomatology in the heart, brain and peripheral vasculature, we argue that the nephrologist should consider taking the lead in better organizing early detection and management of CKD. The nephrologist can guide the general practitioner and general health care workers to offer better preventive care to the subjects at risk of progressive atherosclerotic end-organ damage.

Fibroblast growth factor 21 and protein energy wasting in hemodialysis patients.

INTRODUCTION: Protein energy wasting (PEW) is the most important risk factor for morbidity and mortality in hemodialysis patients. Inadequate dietary protein intake is a frequent cause of PEW. Recent studies have identified fibroblast growth factor 21 (FGF21) as an endocrine protein sensor. This study aims to investigate the potential of FGF21 as a biomarker for protein intake and PEW and to investigate intradialytic FGF21 changes. METHODS: Plasma FGF21 was measured using an enzyme-linked immunoassay. Complete intradialytic dialysate and interdialytic urinary collections were used to calculate 24-h urea excretion and protein intake. Muscle mass was assessed using the creatinine excretion rate and fatigue was assessed using the Short Form 36 and the Checklist Individual Strength. RESULTS: Out of 59 hemodialysis patients (65 ± 15 years, 63% male), 39 patients had a low protein intake, defined as a protein intake less than 0.9 g/kg/24-h. Patients with a low protein intake had nearly twofold higher plasma FGF21 compared to those with an adequate protein intake (FGF21 1370 [795-4034] pg/mL versus 709 [405-1077] pg/mL;P < 0.001). Higher plasma FGF21 was associated with higher odds of low protein intake (Odds Ratio: 3.18 [1.62-7.95] per doubling of FGF21; P = 0.004), independent of potential confounders. Higher plasma FGF21 was also associated with lower muscle mass (std ß: -0.34 [-0.59;-0.09];P = 0.009), lower vitality (std ß: -0.30 [-0.55;-0.05];P = 0.02), and more fatigue (std ß: 0.32 [0.07;0.57];P = 0.01). During hemodialysis plasma FGF21 increased by 354 [71-570] pg/mL, corresponding to a 29% increase. CONCLUSION: Higher plasma FGF21 is associated with higher odds of low protein intake in hemodialysis patients. Secondarily, plasma FGF21 is also associated with lower muscle mass, less vitality, and more fatigue. Lastly, there is an intradialytic increase in plasma FGF21. FGF21 could be a valuable marker allowing for objective assessment of PEW.

Selection on albuminuria enhances the efficacy of screening for cardiovascular risk factors.

BACKGROUND: As many subjects with a cardiovascular (CV) risk factor are undiagnosed, guidelines to prevent cardiovascular disease argue for case finding on those risk factors. Such an approach is, however, labour and cost intensive. An elevated urinary albumin loss is an early marker of vascular damage and is associated with an increased CV risk. As albuminuria is easy to measure, we tested whether a screening approach in which detailed risk factor measurement is done only after selection of subjects with an elevated albuminuria results in a higher yield of subjects at risk. METHODS: A random sample of the general population as investigated in the Prevention of Renal and Vascular End-Stage Disease study was used. Plasma glucose, blood pressure, serum cholesterol and renal function were measured in an overall random sample of the population, in subgroups according to their urinary albumin concentration (UAC) of one first morning urine void and in subgroups in whom the elevated albuminuria level was confirmed with two 24 h urine collections for measurement of urinary albumin excretion (UAE). RESULTS: In the overall population, the number of subjects with any newly found CV risk factor was higher than the number of subjects already known with any CV risk factor (n = 1331 versus 370; 39.2 versus 10.9%). The prevalence of subjects with any newly diagnosed CV risk factor was higher in the group of 267 subjects with a first morning UAC of ≥ 20 mg/L (61.0%; P < 0.05) compared to the overall population (39.2%). Although the sensitivity of a UAC ≥ 20 mg/L to detect a subject with at least one CV risk factor was relatively low (12%), the specificity was very high (96%). The positive predictive value was 70%. When the elevated UAC could be confirmed in two subsequent 24-h urine collections, the diagnostic yield still further improved. CONCLUSION: The prevalence of undiagnosed CV risk factors in the general population is much higher than the prevalence of known risk factors. After a selection of subjects with an elevated albuminuria, the relative prevalence of subjects with newly diagnosed CV risk factors increases while the number of subjects to test for presence of CV risk factors is smaller. Such an approach facilitates a more effective and simple strategy for risk factor screening.

Progression of coronary artery calcification in conventional hemodialysis, nocturnal hemodialysis, and kidney transplantation.

INTRODUCTION: Cardiovascular disease is the leading cause of death in end-stage renal disease (ESRD) and is strongly associated with vascular calcification. An important driver of vascular calcification is high phosphate levels, but these become lower when patients initiate nocturnal hemodialysis or receive a kidney transplant. However, it is unknown whether nocturnal hemodialysis or kidney transplantation mitigate vascular calcification. Therefore, we compared progression of coronary artery calcification (CAC) between patients treated with conventional hemodialysis, nocturnal hemodialysis, and kidney transplant recipients. METHODS: We measured CAC annually up to 3 years in 114 patients with ESRD that were transplantation candidates: 32 that continued conventional hemodialysis, 34 that initiated nocturnal hemodialysis (≥4x 8 hours/week), and 48 that received a kidney transplant. We compared CAC progression between groups as the difference in square root transformed volume scores per year (ΔCAC SQRV) using linear mixed models. Reference category was conventional hemodialysis. RESULTS: The mean age of the study population was 53 ±13 years, 75 (66%) were male, and median dialysis duration was 28 (IQR 12-56) months. Median CAC score at enrollment was 171 (IQR 10-647), which did not differ significantly between treatment groups (P = 0.83). Compared to conventional hemodialysis, CAC progression was non-significantly different in nocturnal hemodialysis -0.10 (95% CI -0.77 to 0.57) and kidney transplantation -0.33 (95% CI -0.96 to 0.29) in adjusted models. CONCLUSIONS: Nocturnal hemodialysis and kidney transplantation are not associated with significantly less CAC progression compared to conventional hemodialysis during up to 3 years follow-up. Further studies are needed to confirm these findings, to determine which type of calcification is measured with CAC in end-stage renal disease, and whether that reflects cardiovascular risk.

Complementary Biomarker Assessment of Components Absorbed from Diet and Creatinine Excretion Rate Reflecting Muscle Mass in Dialysis Patients.

To prevent protein energy malnutrition (PEM) and accumulation of waste products, dialysis patients require diet adjustments. Dietary intake assessed by self-reported intakes often provides biased information and standard 24-h urinary excretion is inapplicable in dialysis patients. We aimed to assess dietary intake via a complementary, less biased biomarker method, and to compare this to dietary diaries. Additionally, we investigated the prospective association of creatinine excretion rate (CER) reflecting muscle mass with mortality. Complete intradialytic dialysate and interdialytic urinary collections were used to calculate 24-h excretion of protein, sodium, potassium, phosphate and creatinine in 42 chronic dialysis patients and compared with protein, sodium, potassium, and phosphate intake assessed by 5-day dietary diaries. Cox regression analyses were employed to investigate associations of CER with mortality. Mean age was 64 ± 13 years and 52% were male. Complementary biomarker assessed (CBA) and dietary assessed (DA) protein intake were significantly correlated (r = 0.610; p < 0.001), but there was a constant bias, as dietary diaries overestimated protein intake in most patients. Correlations were found between CBA and DA sodium intake (r = 0.297; p = 0.056), potassium intake (r = 0.312; p = 0.047) and phosphate uptake/intake (r = 0.409; p = 0.008). However, Bland-Altman analysis showed significant proportional bias. During a median follow-up of 26.6 (25.3⁻31.5) months, nine dialysis patients (23%) died. CER was independently and inversely associated with survival (HR: 0.59 (0.42⁻0.84); p = 0.003). Excretion measurements may be a more reliable assessment of dietary intake in dialysis patients, as this method is relatively free from biases known to exist for self-reported intakes. CER seems to be a promising tool for monitoring PEM.

Long-term clinical parameters after switching to nocturnal haemodialysis: a Dutch propensity-score-matched cohort study comparing patients on nocturnal haemodialysis with patients on three-times-a-week haemodialysis/haemodiafiltration.

OBJECTIVES: Nocturnal haemodialysis (NHD), characterised by 8-hour sessions ≥3 times a week, is known to improve clinical parameters in the short term compared with conventional-schedule haemodialysis (HD), generally 3×3.5-4 hours a week. We studied long-term effects of NHD and used patients on conventional HD/haemodiafiltration (HDF) as controls. DESIGN: Four-year prospective follow-up of patients who switched to NHD; we compared patients with patients on HD/HDF using propensity score matching. SETTING: 28 Dutch dialysis centres. PARTICIPANTS: We included 159 patients starting with NHD any time since 2004, aged 56.7±12.9 years, with median dialysis vintage 2.3 (0.9-5.1) years. We propensity-score matched 100 patients on NHD to 100 on HD/HDF. PRIMARY AND SECONDARY OUTCOME MEASURES: Control of hypertension (predialysis blood pressure, number of antihypertensives), phosphate (phosphate, number of phosphate binders), nutritional status and inflammation (albumin, C reactive protein and postdialysis weight) and anaemia (erythropoiesis-stimulating agent (ESA) resistance). RESULTS: Switching to NHD was associated with a non-significant reduction of antihypertensives compared with HD/HDF (OR <2 types 2.17, 95% CI 0.86 to 5.50, P=0.11); and a prolonged lower need for phosphate binders (OR <2 types 1.83, 95% CI 1.10 to 3.03, P=0.02). NHD was not associated with significant changes in blood pressure or phosphate. NHD was associated with significantly higher albumin over time compared with HD/HDF (0.70 g/L/year, 95% CI 0.10 to 1.30, P=0.02). ESA resistance decreased significantly in NHD compared with HD/HDF, resulting in a 33% lower ESA dose in the long term. CONCLUSIONS: After switching to NHD, the lower need for antihypertensives, phosphate binders and ESA persists for at least 4 years. These sustained improvements in NHD contrast significantly with the course of these parameters during continued treatment with conventional-schedule HD and HDF. NHD provides an optimal form of dialysis, also suitable for patients expected to have a long waiting time for transplantation or those convicted to indefinite dialysis.

Investigation into cardiac sympathetic innervation during the commencement of haemodialysis in patients with chronic kidney disease.

BACKGROUND: Patients with chronic kidney disease (CKD) who undergo chronic haemodialysis (HD) show altered sympathetic tone, which is related to a higher cardiovascular mortality. The purpose of this study was to investigate the effect of transition from pre-HD to HD on cardiac sympathetic innervation. METHODS: Eighteen patients aged 58 ± 18 years (mean ± standard deviation [SD]), 13 males and five females, with stage 5 CKD and nine healthy control subjects aged 52 ± 17 (mean ± SD), three males and six females, were included in this prospective study between May 2010 and December 2013. All patients underwent 123I-labelled meta-iodobenzylguanidine (123I-MIBG) scintigraphy for cardiac sympathetic innervation and electrocardiographically gated adenosine stress and rest 99mTc-labelled tetrofosmin single-photon emission computed tomography for myocardial perfusion imaging prior to (pre-HD) and 6 months after the start of HD. Results of 123I-MIBG scans in patients were compared to controls. Impaired cardiac sympathetic innervation was defined as late heart-to-mediastinum ratio (HMR) < 2.0. RESULTS: Mean late HMR was lower in patients during HD (2.3) than in controls (2.9) (p = 0.035); however, in patients it did not differ between pre-HD and after the start of HD. During HD, two patients showed new sympathetic innervation abnormalities, and in three patients innervation abnormalities seemed to coincide with myocardial perfusion abnormalities. CONCLUSIONS: CKD patients show cardiac sympathetic innervation abnormalities, which do not seem to progress during the maintenance HD. The relationship between sympathetic innervation abnormalities and myocardial perfusion abnormalities in HD patients needs further exploration.

Vitamin C Depletion and All-Cause Mortality in Renal Transplant Recipients.

Vitamin C may reduce inflammation and is inversely associated with mortality in the general population. We investigated the association of plasma vitamin C with all-cause mortality in renal transplant recipients (RTR); and whether this association would be mediated by inflammatory biomarkers. Vitamin C, high sensitive C-reactive protein (hs-CRP), soluble intercellular cell adhesion molecule 1 (sICAM-1), and soluble vascular cell adhesion molecule 1 (sVCAM-1) were measured in a cohort of 598 RTR. Cox regression analyses were used to analyze the association between vitamin C depletion (≤28 µmol/L; 22% of RTR) and mortality. Mediation analyses were performed according to Preacher and Hayes's procedure. At a median follow-up of 7.0 (6.2-7.5) years, 131 (21%) patients died. Vitamin C depletion was univariately associated with almost two-fold higher risk of mortality (Hazard ratio (HR) 1.95; 95% confidence interval (95%CI) 1.35-2.81, p < 0.001). This association remained independent of potential confounders (HR 1.74; 95%CI 1.18-2.57, p = 0.005). Hs-CRP, sICAM-1, sVCAM-1 and a composite score of inflammatory biomarkers mediated 16, 17, 15, and 32% of the association, respectively. Vitamin C depletion is frequent and independently associated with almost two-fold higher risk of mortality in RTR. It may be hypothesized that the beneficial effect of vitamin C at least partly occurs through decreasing inflammation.

The association of albuminuria and high-sensitivity C-reactive protein with the efficacy of HMG-coenzyme A reductase inhibitors for cardiovascular event prevention.

BACKGROUND: It is not clear which hypercholesterolemic patients benefit most from ß-hydroxy-ß-methylglutaryl coenzyme A reductase inhibitors with respect to the prevention of cardiovascular events. Early signs of atherosclerotic vascular damage may identify high-risk patients. DESIGN: We studied whether subjects with hypercholesterolemia will benefit more from starting statin treatment in the case of high albuminuria and/or high-sensitivity C-reactive protein (hsCRP). METHODS: Included were subjects who had hypercholesterolemia at baseline, a negative cardiovascular disease history and who were not treated with statins. In total, 2011 subjects were analysed, of whom 695 started with a statin during a follow-up of 7.0 ± 1.7 years. Adjusted hazard ratios (HRs) for cardiovascular events were calculated in subjects who started versus those who did not start a statin stratified for albuminuria less than or ≥ 15 mg/day and/or hsCRP less than or ≥ 3 mg/L. RESULTS: The start of a statin was associated with a beneficial effect on cardiovascular risk in subjects with high albuminuria (HR 0.38 (0.23-0.60)), while the effect of starting a statin was non-significant in subjects with low albuminuria (HR 0.74 (0.44-1.24), P for interaction < 0.05). The effect of starting a statin was similar in subgroups with high and low hsCRP (P for interaction 0.34). When combining albuminuria and hsCRP subgroups, the start of statin treatment was associated with a lower risk of cardiovascular events dependent on albuminuria and not on the hsCRP level. CONCLUSIONS: The start of statin treatment is associated with a significantly lower absolute as well as relative risk of cardiovascular events in subjects with hypercholesterolemia and elevated albuminuria, whereas these drugs had less effect in subjects with normal albuminuria.