The role of aetiology in cardiac manifestations of chronic kidney disease: the CPH-CKD ECHO study.

PURPOSE: We investigated the associations between cardiac parameters and aetiologies of CKD in an exploratory study. METHODS: The study population consisted of 883 participants, 174 controls and 709 patients with aetiologies of CKD including diabetic nephropathy/renovascular KD in diabetes mellitus, hypertensive/renovascular nephropathy, tubulointerstitial nephritis, glomerulonephritis/vasculitis, polycystic KD (PKD), and CKD of unknown origin. Echocardiographic measures included left ventricular (LV) ejection fraction, global longitudinal, area, and radial strain, E/e' ratio, and LV mass index. These were compared between each aetiological group and controls in unadjusted and adjusted analysis. RESULTS: In unadjusted analysis, patients with diabetic nephropathy/renovascular KD in diabetes mellitus, had impaired LV ejection fraction (Median [IQR]: 56% [49.9,60.69] vs. 60.8% [57.7,64.1]), global longitudinal (mean ± SD: 13.1 ± 3.5% vs. 15.5 ± 2.6%), area (24.1 ± 5.8% vs. 28.5 ± 4.2%), and radial strain (36.2 ± 11.2% vs. 44.1 ± 9.7%), and increased LV mass index (89.1 g/m2 [71.8,104.9] vs. 69,0 g/m2 [57.9,80.8]) and E/e' ratio (10.6 [8.5,12.6] vs. 7 [5.8,8.3], p < 0.001 for all) compared with controls. Associations were similar for CKD of unknown origin. Patients with hypertensive/renovascular nephropathy had impaired global longitudinal and area strain, and higher E/e' ratio. Patients with glomerulonephritis/vasculitis had higher LV mass index, while patients with PKD had better global longitudinal strain than controls. All findings remained significant in adjusted analysis, except for the impaired global longitudinal strain in hypertensive/renovascular nephropathy. CONCLUSION: Glomerulonephritis/vasculitis, hypertensive/renovascular nephropathy, CKD of unknown origin, and diabetic nephropathy/renovascular KD in diabetes mellitus were increasingly associated with adverse cardiac findings, while PKD and tubulointerstitial nephritis were not. Aetiology might play a role regarding the cardiac manifestations of CKD.

Oral anticoagulation for stroke prevention in atrial fibrillation and advanced kidney disease.

Background: The net benefit of oral anticoagulation (OAC) with vitamin K antagonists or direct oral anticoagulants in patients with advanced chronic kidney disease and atrial fibrillation remains uncertain. Objectives: We examined the use, efficacy, and safety of OAC in patients with estimated glomerular filtration rate (eGFR) of <30 mL/min/1.73 m2 (including dialysis-treated patients) and atrial fibrillation. Methods: In a retrospective cohort study, patients diagnosed with atrial fibrillation and eGFR of <30 mL/min/1.73 m2 were identified in national Danish registers between 2010 and 2022. Initiation of OAC was identified based on redemption of a relevant prescription. One-year risks of thromboembolic event, major bleeding, and death associated with OAC and no treatment were computed and standardized to the distribution of risk factors in the sample based on hazards determined in multiple Cox regression models adjusted for age and sex. Results: A total of 3208 patients were included (mean age 80 years, 52.8% males, 20.9% chronic dialysis). OAC was initiated in 1375 (42.9%) patients, of whom 48.1% were vitamin K antagonists and 51.9% were direct oral anticoagulants. One-year risks in nontreated and anticoagulated patients were 4.8% (95% CI, 3.8%-5.7%) and 3.6% (95% CI, 2.8%-4.6%; P = .028) for thromboembolic event, 7.6% (95% CI, 6.6%-8.7%) and 10.5% (95% CI, 9.3%-12.1%; P < .001) for major bleeding, and 36.3% (95% CI, 34.2%-38.3%) and 29.6% (95% CI, 27.6%-31.6%; P < .001) for death, respectively. Conclusion: In a retrospective study on patients with advanced chronic kidney disease and atrial fibrillation, OAC was associated with overall decreased 1-year risk of thromboembolic event and death offset by increased 1-year risk of major bleeding.

Protocol for a randomised controlled trial comparing warfarin with no oral anticoagulation in patients with atrial fibrillation on chronic dialysis: the Danish Warfarin-Dialysis (DANWARD) trial.

INTRODUCTION: Atrial fibrillation is highly prevalent in patients on chronic dialysis. It is unclear whether anticoagulant therapy for stroke prevention is beneficial in these patients. Vitamin K-antagonists (VKA) remain the predominant anticoagulant choice. Importantly, anticoagulation remains inconsistently used and a possible benefit remains untested in randomised clinical trials comparing oral anticoagulation with no treatment in patients on chronic dialysis. The Danish Warfarin-Dialysis (DANWARD) trial aims to investigate the safety and efficacy of VKAs in patients with atrial fibrillation on chronic dialysis. The hypothesis is that VKA treatment compared with no treatment is associated with stroke risk reduction and overall benefit. METHODS AND ANALYSIS: The DANWARD trial is an investigator-initiated trial at 13 Danish dialysis centres. In an open-label randomised clinical trial study design, a total of 718 patients with atrial fibrillation on chronic dialysis will be randomised in a 1:1 ratio to receive either standard dose VKA targeting an international normalised ratio of 2.0-3.0 or no oral anticoagulation. Principal analyses will compare the risk of a primary efficacy endpoint, stroke or transient ischaemic attack and a primary safety endpoint, major bleeding, in patients allocated to VKA treatment and no treatment, respectively. The first patient was randomised in October 2019. Patients will be followed until 1 year after the inclusion of the last patient. ETHICS AND DISSEMINATION: The study protocol was approved by the Regional Research Ethics Committee (journal number H-18050839) and the Danish Medicines Agency (case number 2018101877). The trial is conducted in accordance with the Helsinki declaration and standards of Good Clinical Practice. Study results will be disseminated to participating sites, at research conferences and in peer-reviewed journals. TRIAL REGISTRATION NUMBERS: NCT03862859, EUDRA-CT 2018-000484-86 and CTIS ID 2022-502500-75-00.

Efficacy and safety of oral anticoagulants according to kidney function among patients with atrial fibrillation.

BACKGROUND AND AIMS: Patients with severely reduced kidney function have been excluded from randomized controlled trials and data on the safety and efficacy of direct oral anticoagulants (DOACs) according to kidney function remain sparse. The aim was to evaluate the safety and efficacy of the DOACs across subgroups of kidney function. METHODS: Using multiple Danish nationwide registers and laboratory databases, we included patients initiated on oral anticoagulants (OACs) with atrial fibrillation and available creatinine level and followed patients for 2 years to evaluate occurrence of stroke/thromboembolism (TE) and major bleeding. RESULTS: Among 26 686 included patients, 3667 (13.7%) had an estimated glomerular filtration rate (eGFR) of 30-49 mL/min/1.73 m2 and 596 (2.2%) had an eGFR below 30 mL/min/1.73 m2. We found no evidence of differences regarding the risk of stroke/TE between the OACs (P-value interaction >0.05 for all). Apixaban was associated with a lower 2-year risk of major bleeding compared to vitamin K antagonists (VKA) [hazard ratio 0.79, 95% confidence interval (CI) 0.67-0.93], and the risk difference was significantly larger among patients with reduced kidney function (P-value interaction 0.018). Rivaroxaban was associated with a higher risk of bleeding compared to apixaban (hazard ratio 1.78, 95%CI 1.32-2.39) among patients with eGFR 30-49 mL/min/1.73 m2. CONCLUSIONS: Overall, we found no differences regarding the risk of stroke/TE, but apixaban was associated with a 21% lower relative risk of major bleeding compared to VKA. This risk reduction was even greater when comparing apixaban to VKA among patients with eGFR 15-30 mL/min/1.73 m2, and when comparing apixaban to dabigatran and rivaroxaban among patients with eGFR 30-49 mL/min/1.73 m2.

Post-intervention Adherence to the New Nordic Renal Diet among patients with chronic kidney disease, stages 3 and 4.

The New Nordic Renal Diet (NNRD) is a meal pattern reduced in phosphorus, protein, and sodium for patients with moderate chronic kidney disease. The NNRD showed improvements in metabolic, and physiological outcomes after 26-weeks intervention. In the original study, participants were randomized to NNRD (n = 30), or control (habitual diet) (n = 30). The aim of this study was to explore adherence to the NNRD 3 months after cessation of intervention (follow-up). Fifty-seven participants completed the follow-up visit, which consisted of fasting blood samples and 24 h urine samples. At follow-up, there was no longer a significant reduction in 24 h urine phosphorus excretion in the NNRD group. From intervention to follow-up, 24 h urine phosphorus increased by 63 mg in the NNRD group, vs. -24.1 mg in the control group, between-group difference 87.1 mg (-10.1, 184.3, p = 0.08). Our findings show that more active intervention is needed to support adherence and maintain beneficial effects of the NNRD.

Health effects of the New Nordic Renal Diet in patients with stage 3 and 4 chronic kidney disease, compared with habitual diet: a randomized trial.

BACKGROUND: Chronic kidney disease (CKD) leads to an accumulation of waste products and causes adverse cardiometabolic effects. OBJECTIVES: We investigated the health effects of the New Nordic Renal Diet (NNRD), a novel meal pattern reduced in phosphorus, protein, and sodium. METHODS: A 26-wk randomized trial compared the NNRD with a habitual diet. The NNRD group received weekly home deliveries of food and recipes. Monthly study visits included fasting blood samples, 24-h urine samples, blood pressure, and anthropometric measurements. Intention-to-treat analysis used linear mixed-effects models. RESULTS: Sixty patients, mean estimated glomerular filtration rate (eGFR) 34 mL/min/1.73 m2 and body mass index of 25-27 kg/m2, were included and 58 completed. Metabolic syndrome was present in 53% (NNRD group) and 57% (control group). The NNRD group (n = 30) reduced their 24-h urine phosphorus excretion by 19% (-153 mg; 95% confidence interval [CI]: -210, -95), control group (n = 30) (no change), between-group difference -171 mg (95% CI: -233, -109; P < 0.001). Proteinuria was reduced by 39% in the NNRD group (-0.33 g/d; 95% CI: -0.47, -0.18), control group (no change), between-group difference -0.34 g/d (95% CI: -0.52, -0.17; P < 0.001). Plasma urea was reduced by -1.5 mmol/L in the NNRD group (95% CI: -2.1, -0.9), control group (no change), between-group difference -1.4 mmol/L (95% CI: -2.0, -0.7; P < 0.001). Systolic blood pressure fell by -5.2 mmHg in the NNRD group (95% CI: -8.4, -2.1), control group (no change), between-group difference -3.9 mmHg (95% CI; -7.6, -0.2; P = 0.04). The NNRD group lost -1.7 kg (95% CI: -2.6, -0.8), control group (no change), between-group difference -2.0 kg (95% CI: -3.0, -1.0; P < 0.001). There were no effects on eGFR during the 26-wk intervention. CONCLUSION: NNRD in moderate CKD reduces phosphorus excretion, proteinuria, systolic blood pressure, and weight, mainly by reducing abdominal fat. This trial was registered at clinicaltrials.gov as NCT04579315.

The New Nordic Renal Diet Induces a Pronounced Reduction of Urine Acid Excretion and Uremic Toxins in Chronic Kidney Disease Patients (Stage 3 and 4).

OBJECTIVE: Metabolic acidosis and the uremic toxins, indoxyl sulfate (IS) and p-cresyl sulfate (PCS), are associated with increased risks of kidney disease progression, muscle catabolism, cardiovascular disease, and mortality in patients with chronic kidney disease (CKD). The New Nordic Renal Diet (NNRD) is a plant-focused meal pattern, with reduced phosphorus and protein content compared to an average Danish diet. Due to a higher amount of plant-based products, we hypothesized that NNRD would reduce renal excretion of acids and uremic toxins. Thus, we evaluated the effects of NNRD on metabolic acidosis and uremic toxins in patients with moderate CKD, stages 3-4. DESIGN AND METHODS: This post hoc analysis is based on a randomized controlled crossover trial comparing 1 week of the NNRD to a control 1-week period of an average Danish diet, in patients with CKD stages 3 and 4. Urine pH and urine excretion of bicarbonate, ammonium, titratable acids, IS, and PCS alongside plasma total CO2 (tCO2) were measured at days 1, 4, and 7 in 18 patients. RESULTS: After 7 days on NNRD 24-hour urine net acid excretion was decreased by 80% (P < .001), 24-hour urine excretion of ammonium and bicarbonate decreased by 34% (P < .001), and increased by 678% (P < .001), respectively, compared with the control period. Plasma tCO2 was increased by 8% (P = .005). Moreover, 24-hour urine excretion of PCS and IS were reduced by 31% (P = .018) and 29% (P < .001), respectively. CONCLUSION: One week of NNRD in patients suffering from moderate CKD effectively improved metabolic acidosis with a marked reduction in urine net acid excretion that included a large increase in urine bicarbonate excretion. In addition, NNRD reduced urinary excretion of the uremic toxins PCS and IS. These results encourage further investigations of the long-term effects of NNRD on renal protection in patients with CKD.

Associations Between Albuminuria, Estimated GFR and Cardiac Phenotype in a Cohort with Chronic Kidney Disease: The CPH-CKD ECHO Study.

OBJECTIVE: Echocardiographic findings in chronic kidney disease (CKD) vary. We sought to estimate the prevalence of abnormal cardiac structure and function in patients with CKD and their association to estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (UACR). METHODS: We prospectively enrolled 825 outpatients with non-dialysis-dependent CKD, mean age 58± 13 yrs, and 175 matched healthy controls, mean age 60±12 yrs. Echocardiography included assessment of left ventricular (LV) hypertrophy, LV ejection fraction (LVEF), global longitudinal strain (GLS) and diastolic dysfunction according to ASE/EACVI guidelines. RESULTS: LV hypertrophy was found in 9% of patients vs. 1.7% of controls (p=0.005) was independently associated with UACR (p=0.002). Median LVEF was 59.4% (IQR 55.2, 62.8) in patients vs. 60.8% (57.7, 64.1) in controls (p=0.002). GLS was decreased in patients with eGFR <60ml/min/1.73m² (-17.6%±3.1%) vs. patients with higher eGFR (19.0%±2.2%, p<0.001), who were similar to controls. Diastolic dysfunction was detected in 55% of patients and in 34% of controls. LIMITATIONS: Non-random sampling, cross-sectional analysis. CONCLUSIONS: We report lower prevalence of hypertrophy than previous studies, but similar measurements of systolic and diastolic function. Cardiac remodeling in CKD may be influenced by treatment modalities, demographics, comorbidities and renal pathology.

Left ventricular structure and function in patients with chronic kidney disease assessed by 3D echocardiography: the CPH-CKD ECHO study.

Cardiovascular disease is the leading cause of mortality amongst patients with chronic kidney disease (CKD). This is the first study using 3-dimensional echocardiography (3DE) to investigate associations between adverse changes of the left ventricle, and different stages of CKD. Participants were recruited from the Copenhagen CKD cohort study and the Herlev-Gentofte CKD cohort study. Patients were stratified according to GFR category (G1 + 2: eGFR ≥ 60 mL/min/1.73 m2, G3: eGFR = 30-59 mL/min/1.73 m2, and G4 + 5: eGFR ≤ 29 mL/min/1.73 m2), and according to albuminuria (A1: UACR < 30 mg/g, A2: 30-300 mg/g, A3: > 300 mg/g). Echocardiograms were analysed for left ventricular (LV) mass index (LVMi), LV ejection fraction (LVEF), and global strain measures. In adjusted analysis, eGFR groups were adjusted for confounders and albuminuria category, while albuminuria groups were adjusted for confounders and GFR category. The study population consisted of 662 outpatients with CKD and 169 controls. Mean age was 57 ± 13 years, and 61% were males. Mean LVEF and global longitudinal strain (GLS) were increasingly impaired across eGFR groups: LVEF = 60.1%, 58.4%, and 57.8% (p = 0.013), GLS = - 16.1%, - 14.8%, and - 14.6% (p < 0.0001) for G1 + 2, G3, and G4 + 5. LVMi and prevalence of LV hypertrophy increased with albuminuria severity: mean LVMi = 87.9 g/m2, 88.1 g/m2, and 92.1 g/m2 (p = 0.007) from A1-3. Adjusted analysis confirmed reduced LVEF in G3 compared with G1 + 2, and increased LVMi in A3 compared with A1. Increasingly impaired eGFR was associated with adverse changes in LV systolic function, while albuminuria was associated with adverse changes in LV mass assessed by 3DE. Their associations were independent of each other.

Study protocol: long-term effect of the New Nordic Renal Diet on phosphorus and lipid homeostasis in patients with chronic kidney disease, stages 3 and 4: a randomised controlled trial.

INTRODUCTION: Chronic kidney disease (CKD) causes severe disturbances in phosphate metabolism. New Nordic Renal Diet (NNRD) is a new dietary concept designed by the present research group that aims to offer patients with moderate CKD a whole food approach with a markedly reduction in dietary phosphorus intake, corresponding to 850 mg/day. The present protocol describes a randomised controlled trial aiming to test the long-term effects of dietary intervention with NNRD versus a non-restricted habitual diet on important parameters of phosphorus and lipid homeostasis. METHODS AND ANALYSIS: This trial will be executed at the Department of Nephrology, Rigshospitalet, University of Copenhagen, Denmark. Sixty patients aged >18 years with CKD stages 3 and 4 (estimated glomerular filtration rate between 15 and 45 mL/min) will be recruited and randomly assigned to the intervention or control group. The other inclusion criterion includes a medically stable condition for at least 2 months prior to the start of the study. Exclusion criteria are treatment with phosphate binders, metabolic disorders that require specific dietary regulation, pregnancy and breast feeding, any types of food allergies or those who are vegans. The observation period is 26 weeks including seven study visits at the outpatient clinic combined with a weekly telephone consultation in both groups. A follow-up visit 3 months after study completion finalises the intervention. The primary outcome is the difference in the change in 24-hour urine phosphorus excretion from baseline to week 26 between the two study groups. Secondary outcomes include changes in phosphate-related and lipid metabolism-related blood and urine biochemistry, blood pressure and body composition. Moreover, we wish to explore adherence to the diet as well as quality of life. ETHICS AND DISSEMINATION: The study has been approved by the Scientific Ethical Committee of the Capital Region of Denmark and the Danish Data Protection Agency. The results of the studies will be presented at national and international scientific meetings, and publications will be submitted to peer-reviewed journals. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (wwwclinicaltrialsgov) Registry (NCT04579315). PROTOCOL VERSION: The protocol, version 2, has been approved by the Ethical Committee Denmark on 18 September 2020. The protocol has also been approved by Data Protection Regulation and Data Protection Law on 15 September 2020. This study protocol is in accordance with the Standard Protocol Items: Recommendations for International Trials.

Kidney function and the prognostic value of myocardial performance index.

A decreased glomerular filtration rate (GFR) is a risk factor for cardiovascular disease even after adjustment for conventional risk factors. The myocardial performance index (MPI) is defined as (isovolumetric relaxation time (IVRT) + isovolumetric contraction time (IVCT))/ejection time (ET). It has been shown to be an independent predictor of cardiovascular events. We hypothesized the MPI could prove valuable for assessing cardiac risk in subjects of the general population with decreased estimated GFR (eGFR). MPI was measured in 1915 subjects from a large general population prospective cohort study using color tissue Doppler imaging (TDI) M-mode through the mitral valve. We compared the prognostic capabilities of the MPI between subjects with eGFR ≥ 75 mL/min/1.73 m2 and subjects with eGFR < 75 mL/min/1.73 m2 using multivariable adjusted Cox regression models. The composite endpoint was heart failure, myocardial infarction or cardiovascular death. Mean age was 58 years (SD 16.2), 58% were women, 42% had hypertension and 8.3% diabetes. During a median follow-up time of 12.4 years [IQR 10.6-12.7 years] 269 participants reached the combined endpoint. eGFR modified the prognostic capability of MPI (p-value for interaction < 0.001): After multivariable adjustment, MPI remained an independent predictor of the composite endpoint only in participants with eGFR < 75 mL/min/1.73 m2: HR 1.18 (95% CI 1.02-1.38), p = 0.03, vs. in subjects with eGFR ≥ 75 mL/min/1.73 m2: HR 1.14 (95% CI 0.94-1.39), p = 0.17. These results suggest the MPI could be particularly valuable for identifying elevated cardiac risk in individuals from the general population with decreased eGFR.

Outcome of Dialysis-Requiring Acute Kidney Injury in Patients With Infective Endocarditis: A Nationwide Study.

BACKGROUND: Infective endocarditis (IE) may be complicated by acute kidney injury, yet data on the use of dialysis and subsequent reversibility are sparse. METHODS: Using Danish nationwide registries, we identified patients with first-time IE from 2000 to 2017. Dialysis-naïve patients were grouped into: those with and those without dialysis during admission with IE. Continuation of dialysis was followed 1 year postdischarge. Multivariable adjusted Cox proportional hazard analysis was used to examine 1-year mortality for patients surviving IE according to use of dialysis. RESULTS: We included 7307 patients with IE; 416 patients (5.7%) initiated dialysis treatment during admission with IE and these were younger, had more comorbidities and more often underwent cardiac valve surgery compared with nondialysis patients (47.4% vs 20.9%). In patients with both cardiac valve surgery and dialysis treatment (n = 197), 153 (77.7%) initiated dialysis on or after the date of surgery. The in-hospital mortality was 40.4% and 19.0% for patients with and without dialysis, respectively (P < .0001). Of those who started dialysis and survived hospitalization, 21.6% continued dialysis treatment within 1 year after discharge. In multivariable adjusted analysis, dialysis during admission with IE was associated with an increased 1-year mortality from IE discharge, hazard ratio = 1.64 (95% confidence interval, 1.21-2.23). CONCLUSION: In dialysis-naïve patients with IE, approximately 1 in 20 patients initiated dialysis treatment during admission with IE. Dialysis identified a high-risk group with an in-hospital mortality of 40% and an approximate 20% risk of continued dialysis. Those with dialysis during admission with IE showed worse long-term outcomes than those without.

Regional distribution and severity of arterial calcification in patients with chronic kidney disease stages 1-5: a cross-sectional study of the Copenhagen chronic kidney disease cohort.

BACKGROUND: Patients with chronic kidney disease (CKD) and arterial calcification are considered at increased risk of adverse cardiovascular outcomes. However, the optimal site for measurement of arterial calcification has not been determined. The primary aim of this study was to examine the pattern of arterial calcification in different stages of CKD. METHODS: This was an observational, cross-sectional study that included 580 individuals with CKD stages 1-5 (no dialysis) from the Copenhagen CKD Cohort. Calcification of the carotid, coronary and iliac arteries, thoracic and abdominal aorta was assessed using non-contrast multidetector computed tomography scans and quantified according to the Agatston method. Based on the distribution of Agatston scores in the selected arterial region, the subjects were divided into calcium score categories of 0 (no calcification), 1-100, 101-400 and > 400. RESULTS: Participants with CKD stages 3-5 had the highest prevalence of calcification and the highest frequency of calcium scores > 400 in all arterial sites. Calcification in at least one arterial site was present in > 90% of patients with CKD stage 3. In all five CKD stages prevalence of calcification was greatest in both the thoracic and abdominal aorta, and in the iliac arteries. These arterial sites also showed the highest calcium scores. High calcium scores (> 400) in all five arterial regions were independently associated with prevalent cardiovascular disease. In multivariable analyses, after adjusting for cardiovascular risk factors, declining creatinine clearance was associated with increasing calcification of the coronary arteries (p = 0.012) and the thoracic aorta (p = 0.037) only. CONCLUSIONS: Arterial calcification is highly prevalent throughout all five CKD stages and is most prominent in both the thoracic and abdominal aorta, and in the iliac arteries. Follow-up studies are needed to explore the potential of extracardiac calcification sites in prediction of cardiovascular events in the CKD population.

Renal 123I-MIBG Uptake before and after Live-Donor Kidney Transplantation.

Increased sympathetic activity is suggested to be part of the pathogenesis in several diseases. Methods to evaluate sympathetic activity and renal nervous denervation procedural success are lacking. Scintigraphy using the norepinephrine analog Iodine-123 Metaiodobenzylguanidine (123I-MIBG) might provide information on renal sympathetic nervous activity. Renal transplantation induces complete denervation of the kidney and as such represents an ideal model to evaluate the renal 123I-MIBG scintigraphy method. The aim of this study was to evaluate whether renal 123I-MIBG scintigraphy can detect changes in renal sympathetic nervous activity following renal transplantation. Renal 123I-MIBG scintigraphy was performed in eleven renal transplant recipients at 1, 3, and 6 months following transplantation and in their respective living donors prior to their kidney donation. Relative uptake as well as washout was obtained. In transplanted patients, the relative 4 h uptake of 123I-MIBG, as measured by the kidney/background ratio, was 2.7 (0.4) (mean (SD)), 2.7 (0.5), and 2.5 (0.4) at 1, 3, and 6 months post-transplantation, respectively, as compared with the 4.0 (0.4) value in the donor kidney before donor nephrectomy (p < 0.01). There was no significant change in washout-rate between pre-transplantation and any of the follow-up time points. Living donor kidney transplantation was at 6 months post transplantation, associated with an almost 40% reduction in the relative 4 h 123I-MIBG uptake of the kidney. Further studies will help to fully establish its implications as a marker of renal innervation or denervation.

Collagen turnover profiles in chronic kidney disease.

Renal fibrosis is a hallmark of chronic kidney disease (CKD) caused by an imbalance between formation and degradation of extracellular matrix proteins. We investigated the collagen turnover profile of 81 non-dialysis CKD stage 2-5 patients by measuring peptides reflecting formation and degradation of collagen type (COL) I, III, IV, and VI. Based on the collagen turnover profile, we identified four clusters of patients. Cluster 1 contained one patient with prostate cancer, who had a distinct collagen turnover. The other clusters generally had severe (Cluster 2), moderate (Cluster 4), or mild CKD (Cluster 3). Cluster 4 patients were characterized by higher levels of COL III, COL IV, and COL VI (all p < 0.001) degradation fragments in plasma, while patients in Clusters 2 and 4 had higher levels of COL VI formation (p < 0.05). COL IV fragments in plasma were lower in Cluster 2 (p < 0.01). Urinary COL III fragments decreased from Cluster 3 to 4, and from Cluster 4 to 2 (both p < 0.001). We show that patients with similar kidney function have a different collagen remodeling profile, suggesting that different phenotypes exist with different disease activity and potentially disease progression. Biomarkers of collagen remodeling could provide additional information to traditional markers of renal function.

Non-vitamin K antagonist oral anticoagulants vs. vitamin-K antagonists in patients with atrial fibrillation and chronic kidney disease: a nationwide cohort study.

BACKGROUND: We aimed to compare effectiveness and safety of non-vitamin K antagonist oral anticoagulants (NOACs) versus vitamin-K antagonists (VKA) in atrial fibrillation (AF) patients with chronic kidney disease (CKD) not receiving dialysis. METHODS: By using personal identification numbers, we cross-linked individual-level data from Danish administrative registries. We identified every citizen with a prior diagnosis of AF and CKD who initiated NOAC or VKA (2011-2017). An external analysis of 727 AF patients with CKD (no dialysis) was performed to demonstrate level of kidney function in a comparable population. Study outcomes included incidents of stroke/thromboembolisms (TEs), major bleedings, myocardial infarctions (MIs), and all-cause mortality. We used Cox proportional hazards models to determine associations between oral anticoagulant treatment and outcomes. RESULTS: Of 1560 patients included, 1008 (64.6%) initiated VKA and 552 (35.4%) initiated NOAC. In a comparable population we found that 95.3% of the patients had an estimated glomerular filtration rate (eGFR) < 59 mL/min. Patients treated with NOAC had a significantly decreased risk of major bleeding (hazard ratio (HR): 0.47, 95% confidence interval (CI): 0.26-0.84) compared to VKA. There was not found a significant association between type of anticoagulant and risk of stroke/TE (HR: 0.83, 95% CI: 0.39-1.78), MI (HR: 0.45, 95% CI: 0.18-1.11), or all-cause mortality (HR: 0.99, 95% CI: 0.77-1.26). CONCLUSION: NOAC was associated with a lower risk of major bleeding in patients with AF and CKD compared to VKA. No difference was found in risk of stroke/TE, MI, and all-cause mortality.

Increased risk of Staphylococcus aureus bacteremia in hemodialysis-A nationwide study.

INTRODUCTION: Staphylococcus aureus bacteremia (SAB) is a high-risk infection and feared complication related to hemodialysis. This study aimed to investigate incidence and risk factors for SAB depending on hemodialysis access type. METHODS: The Danish National Registry on Regular Dialysis and Transplantation was used to identify patients from January 1, 1996 to December 31, 2011 with end-stage kidney disease. Patients were followed until death, the first episode of SAB, or end of study (December 31, 2011). Independent risk factors were assessed by multivariable Poisson regression with time-updated exposure variables. FINDINGS: Total of 9997 patients were included. The initial modality of renal replacement therapy was hemodialysis in 6826 patients and peritoneal dialysis in 2882 patients; 289 patients had preemptive kidney transplantation. SAB occurred in 1278 patients (12.8%). The incidence rate of SAB declined after 90 days and leveled off after 270 days in hemodialysis, peritoneal dialysis, and kidney transplanted. As compared to peritoneal dialysis, the adjusted rate ratio (RR) for SAB was 7.42 (95% CI 5.63-9.79) in uncuffed central venous catheter (CVC), 5.68 (95% CI 4.39-7.36) in cuffed CVC, 4.43 (95% CI 2.10-9.53) in arteriovenous graft, and 3.40 (95% CI 2.79-4.15) in arteriovenous fistula. SAB risk did not differ between uncuffed and cuffed CVC. The risk of SAB was increased during the first three months of renal replacement therapy especially for CVC (RR 11.37 [95% CI7.09-18.22]) compared with peritoneal dialysis. Diabetes mellitus (RR 1.35 [95% CI 1.20-1.51]) and male sex (RR 1.15 [95% CI 1.03-1.29]) were also associated with SAB. DISCUSSION: Patients on hemodialysis had a high incidence rate of SAB, particularly those undergoing hemodialysis via CVC. SAB risk was comparable for cuffed and uncuffed CVC. Diabetes mellitus, male sex, and the first three months in renal replacement therapy were independently associated with SAB.

Short-term effect of the New Nordic Renal Diet on phosphorus homoeostasis in chronic kidney disease Stages 3 and 4.

BACKGROUND: The New Nordic Diet is a food concept favouring organically produced food items, fruits, vegetables, whole grains and fish. We investigated the short-term effects of a modified phosphorus-reduced New Nordic Renal Diet (NNRD) in chronic kidney disease (CKD) patients on important parameters of phosphorus homoeostasis. METHODS: The NNRD contained a total of 850 mg phosphorus/day. A total of 18 patients, CKD Stages 3 and 4 were studied in a randomized crossover trial comparing a 1-week control period of the habitual diet with a 1-week period of the NNRD. Data were obtained at baseline and during 1 week of dietary intervention (habitual diet versus NNRD) by collecting fasting blood samples and 24-h urine collections. The primary outcome was the difference in the change in 24-h urine phosphorus excretion from baseline to Day 7 between the NNRD and habitual diet periods. Secondary outcomes were changes in the fractional excretion of phosphorus, fibroblast growth factor 23 (FGF23) and plasma phosphate. RESULTS: As compared with the habitual diet, 24-h urine phosphorus excretion was reduced in the NNRD by 313 mg/day (P < 0.001). The mean baseline phosphorus was 875 ± 346 mg/day and was decreased by 400 ± 256 mg/day in the NNRD and 87 ± 266 mg/day in the habitual diet. The 24-h urine fractional excretion of phosphorus decreased by 11% (P < 0.001) and FGF23 decreased by 30 pg/mL (P = 0.03) with the NNRD compared with the habitual diet. Plasma phosphate did not change. CONCLUSION: This study demonstrates that dietary phosphorus restriction in the context of the NNRD is feasible and has positive effects on phosphorus homeostasis in CKD patients.

The impact of hemodialysis on mortality risk and cause of death in Staphylococcus aureus endocarditis.

BACKGROUND: The risk of infective endocarditis (IE) is markedly increased in patients receiving chronic hemodialysis compared with the general population, but outcome data are sparse. The present study investigated causes and risk factors of mortality in a hemodialysis-treated end-stage kidney disease- (ESKD) and a non-ESKD population with staphylococcus (S.) aureus endocarditis. METHODS: Hemodialysis-treated ESKD patients with S. aureus endocarditis were identified from Danish National Registries and Non-ESKD patients from The East Danish Database on Endocarditis. For establishing the cause of death The Danish Registry of Cause of Death was used. Independent risk factors of outcome were identified in multivariable Cox regression models. RESULTS: One hundred twenty-one hemodialysis patients and 190 non-ESKD patients with S. aureus endocarditis were included during 1996-2012 and 2002-2012, respectively. The all-cause in-hospital mortality was 22.3% in hemodialysis- and 24.7% in non-ESKD patients. One-year mortality, excluding in-hospital mortality, was 26.4% in hemodialysis patients and 15.2% in non-ESKD patients. The hazard ratio of all-cause mortality in hemodialysis was 2.64 (95% CI 1.70-4.10) at > 70 days after admission compared with non-ESKD. Age (HR 1.03 (95% CI 1.02-1.04)) and diabetes mellitus (HR 2.17 (95% CI 1.54-3.10)) were independent risk factors of all-cause mortality. The hazard ratio of cardiovascular death in hemodialysis was 3.20 (95% CI 1.78-5.77) at > 81 days after admission compared with non-ESKD. Age and diabetes mellitus were independently related to cardiovascular death. CONCLUSION: All-cause in-hospital mortality rates were similar in hemodialysis and non-ESKD patients with S. aureus endocarditis whereas one-year mortality rates were significantly increased in the hemodialysis population.

Renal Function, Time in Therapeutic Range and Outcomes in Warfarin-Treated Atrial Fibrillation Patients: A Retrospective Analysis of Nationwide Registries.

Patients with severely reduced renal function have been excluded from randomized controlled trials of oral anticoagulation in atrial fibrillation (AF). Warfarin treatment in this population is controversial and data on anticoagulation control and the impact on adverse outcomes are needed. By individual-level linkage of nationwide registries, we identified all patients discharged from hospitals with AF in Denmark between 1997 and 2011. Patients with available serum creatinine tests were categorized according to the estimated glomerular filtration rate (eGFR). Time in therapeutic range (TTR) was calculated using the Rosendaal method. The risk of stroke and bleeding was estimated using multivariable Cox regression analyses with eGFR and TTR estimated time dependently throughout follow-up. We identified 10,423 warfarin-treated AF patients with available international normalized ratio and creatinine tests; 5,527 with eGFR > 60 mL/min/1.73 m2, 4,524 with eGFR 30­60 mL/min/1.73 m2 and 372 with eGFR < 30 mL/min/1.73 m2. Median TTR was 66.7, 61.2 and 49.7% in patients with eGFR > 60, 30­59 and <30 mL/min/1.73 m2, respectively. A TTR < 70% was associated with a higher risk of stroke/thromboembolism (hazard ratio [HR]: 1.39; 95% confidence interval [CI]: 1.20­1.60) and bleeding (HR: 1.22; 95% CI: 1.05­1.42) among patients with eGFR of 30 to 59 and a trend towards higher risk of stroke/thromboembolism (HR: 1.24; 95% CI: 0.86­1.80) and bleeding (HR: 1.17; 95% CI: 0.83­1.65) among patients with eGFR < 30 mL/min/1.73 m2. In conclusion, warfarin-treated AF patients with reduced renal function have suboptimal anticoagulation control which was related to the risk of adverse outcomes.