TY - JOUR A1 - Allignol, Arthur A1 - Schumacher, Martin A1 - Wanner, Christoph A1 - Drechsler, Christiane A1 - Beyersmann, Jan T1 - Understanding competing risks: a simulation point of view JF - BMC Medical Research Methodology N2 - Background: Competing risks methodology allows for an event-specific analysis of the single components of composite time-to-event endpoints. A key feature of competing risks is that there are as many hazards as there are competing risks. This is not always well accounted for in the applied literature. Methods: We advocate a simulation point of view for understanding competing risks. The hazards are envisaged as momentary event forces. They jointly determine the event time. Their relative magnitude determines the event type. 'Empirical simulations' using data from a recent study on cardiovascular events in diabetes patients illustrate subsequent interpretation. The method avoids concerns on identifiability and plausibility known from the latent failure time approach. Results: The 'empirical simulations' served as a proof of concept. Additionally manipulating baseline hazards and treatment effects illustrated both scenarios that require greater care for interpretation and how the simulation point of view aids the interpretation. The simulation algorithm applied to real data also provides for a general tool for study planning. Conclusions: There are as many hazards as there are competing risks. All of them should be analysed. This includes estimation of baseline hazards. Study planning must equally account for these aspects. KW - Cumulative incidence function KW - Clinical-trials KW - Sample-sizes KW - Regression KW - Subdistribution KW - Hazards KW - Model KW - Probabilities KW - Tests Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142811 VL - 11 IS - 86 ER - TY - JOUR A1 - Beck, Hanna A1 - Titze, Stephanie I. A1 - Hübner, Silvia A1 - Busch, Martin A1 - Schlieper, Georg A1 - Schultheiss, Ulla T. A1 - Wanner, Christoph A1 - Kronenberg, Florian A1 - Krane, Vera A1 - Eckardt, Kai-Uwe A1 - Köttgen, Anna T1 - Heart Failure in a Cohort of Patients with Chronic Kidney Disease: The GCKD Study JF - PLoS ONE N2 - Background and Aims Chronic kidney disease (CKD) is a risk factor for development and progression of heart failure (HF). CKD and HF share common risk factors, but few data exist on the prevalence, signs and symptoms as well as correlates of HF in populations with CKD of moderate severity. We therefore aimed to examine the prevalence and correlates of HF in the German Chronic Kidney Disease (GCKD) study, a large observational prospective study. Methods and Results We analyzed data from 5,015 GCKD patients aged 18-74 years with an estimated glomerular filtration rate (eGFR) of <60 ml/min/1.73m\(^{2}\) or with an eGFR >= 60 and overt proteinuria (>500 mg/d). We evaluated a definition of HF based on the Gothenburg score, a clinical HF score used in epidemiological studies (Gothenburg HF), and self-reported HF. Factors associated with HF were identified using multivariable adjusted logistic regression. The prevalence of Gothenburg HF was 43% (ranging from 24% in those with eGFR >90 to 59% in those with eGFR<30 ml/min/1.73m2). The corresponding estimate for self-reported HF was 18% (range 5%-24%). Lower eGFR was significantly and independently associated with the Gothenburg definition of HF (p-trend <0.001). Additional significantly associated correlates included older age, female gender, higher BMI, hypertension, diabetes mellitus, valvular heart disease, anemia, sleep apnea, and lower educational status. Conclusions The burden of self-reported and Gothenburg HF among patients with CKD is high. The proportion of patients who meet the criteria for Gothenburg HF in a European cohort of patients with moderate CKD is more than twice as high as the prevalence of self-reported HF. However, because of the shared signs, symptoms and medications of HF and CKD, the Gothenburg score cannot be used to reliably define HF in CKD patients. Our results emphasize the need for early screening for HF in patients with CKD. KW - global outcomes KW - cardiovascularm disease KW - consensus conference KW - men born KW - insufficiency KW - epidemiology KW - European Society KW - atherosclerosis risk KW - United States KW - glomerular filtration rate KW - KDIGO Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143315 VL - 10 IS - 4 ER - TY - JOUR A1 - Betz, Boris A1 - Schneider, Reinhard A1 - Kress, Tobias A1 - Schick, Martin Alexander A1 - Wanner, Christoph A1 - Sauvant, Christoph T1 - Rosiglitazone Affects Nitric Oxide Synthases and Improves Renal Outcome in a Rat Model of Severe Ischemia/Reperfusion Injury JF - PPAR Research N2 - Background. Nitric oxide (NO)-signal transduction plays an important role in renal ischemia/reperfusion (I/R) injury. NO produced by endothelial NO-synthase (eNOS) has protective functions whereas NO from inducible NO-synthase (iNOS) induces impairment. Rosiglitazone (RGZ), a peroxisome proliferator-activated receptor (PPAR)-gamma agonist exerted beneficial effects after renal I/R injury, so we investigated whether this might be causally linked with NOS imbalance. Methods. RGZ (5 mg/kg) was administered i.p. to SD-rats (f) subjected to bilateral renal ischemia (60 min). Following 24 h of reperfusion, inulin-and PAH-clearance as well as PAH-net secretion were determined. Morphological alterations were graded by histopathological scoring. Plasma NOx-production was measured. eNOS and iNOS expression was analyzed by qPCR. Cleaved caspase 3 (CC3) was determined as an apoptosis indicator and ED1 as a marker of macrophage infiltration in renal tissue. Results. RGZ improves renal function after renal I/R injury (PAH-/inulin-clearance, PAH-net secretion) and reduces histomorphological injury. Additionally, RGZ reduces NOx plasma levels, ED-1 positive cell infiltration and CC3 expression. iNOS-mRNA is reduced whereas eNOS-mRNA is increased by RGZ. Conclusion. RGZ has protective properties after severe renal I/R injury. Alterations of the NO pathway regarding eNOS and iNOS could be an explanation of the underlying mechanism of RGZ protection in renal I/R injury. KW - dysfunction KW - activated-receptor gamma KW - ischemia-reperfusion injury KW - failure KW - kidney KW - agnoists KW - mices KW - inos KW - pathophysiology KW - pioglitazone Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130872 VL - 2012 IS - Article ID 219319 ER - TY - JOUR A1 - Busch, Martin A1 - Nadal, Jennifer A1 - Schmid, Matthias A1 - Paul, Katharina A1 - Titze, Stephanie A1 - Hübner, Silvia A1 - Köttgen, Anna A1 - Schultheiss, Ulla T. A1 - Baid-Agrawal, Seema A1 - Lorenzen, Johan A1 - Schlieper, Georg A1 - Sommerer, Claudia A1 - Krane, Vera A1 - Hilge, Robert A1 - Kielstein, Jan T. A1 - Kronenberg, Florian A1 - Wanner, Christoph A1 - Eckardt, Kai-Uwe A1 - Wolf, Gunter T1 - Glycaemic control and antidiabetic therapy in patients with diabetes mellitus and chronic kidney disease - cross-sectional data from the German Chronic Kidney Disease (GCKD) cohort JF - BMC Nephrology N2 - Background Diabetes mellitus (DM) is the leading cause of end-stage renal disease. Little is known about practice patterns of anti-diabetic therapy in the presence of chronic kidney disease (CKD) and correlates with glycaemic control. We therefore aimed to analyze current antidiabetic treatment and correlates of metabolic control in a large contemporary prospective cohort of patients with diabetes and CKD. Methods The German Chronic Kidney Disease (GCKD) study enrolled 5217 patients aged 18–74 years with an estimated glomerular filtration rate (eGFR) between 30–60 mL/min/1.73 m2 or proteinuria >0.5 g/d. The use of diet prescription, oral anti-diabetic medication, and insulin was assessed at baseline. HbA1c, measured centrally, was the main outcome measure. Results At baseline, DM was present in 1842 patients (35 %) and the median HbA1C was 7.0 % (25th–75th percentile: 6.8–7.9 %), equalling 53 mmol/mol (51, 63); 24.2 % of patients received dietary treatment only, 25.5 % oral antidiabetic drugs but not insulin, 8.4 % oral antidiabetic drugs with insulin, and 41.8 % insulin alone. Metformin was used by 18.8 %. Factors associated with an HbA1C level >7.0 % (53 mmol/mol) were higher BMI (OR = 1.04 per increase of 1 kg/m2, 95 % CI 1.02–1.06), hemoglobin (OR = 1.11 per increase of 1 g/dL, 95 % CI 1.04–1.18), treatment with insulin alone (OR = 5.63, 95 % CI 4.26–7.45) or in combination with oral antidiabetic agents (OR = 4.23, 95 % CI 2.77–6.46) but not monotherapy with metformin, DPP-4 inhibitors, or glinides. Conclusions Within the GCKD cohort of patients with CKD stage 3 or overt proteinuria, antidiabetic treatment patterns were highly variable with a remarkably high proportion of more than 50 % receiving insulin-based therapies. Metabolic control was overall satisfactory, but insulin use was associated with higher HbA1C levels. KW - Chronic kidney disease KW - Glycaemic control KW - Hemoglobin A1C KW - Insulin therapy KW - Oral antidiabetic drugs KW - Diabetes mellitus Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164687 VL - 17 IS - 59 ER - TY - JOUR A1 - Carsten A., Böger A1 - Gorski, Mathias A1 - Li, Man A1 - Hoffmann, Michael M. A1 - Huang, Chunmei A1 - Yang, Qiong A1 - Teumer, Alexander A1 - Krane, Vera A1 - O'Seaghdha, Conall M. A1 - Kutalik, Zoltán A1 - Wichmann, H.-Erich A1 - Haak, Thomas A1 - Boes, Eva A1 - Coassin, Stefan A1 - Coresh, Josef A1 - Kollerits, Barbara A1 - Haun, Margot A1 - Paulweber, Bernhard A1 - Köttgen, Anna A1 - Li, Guo A1 - Shlipak, Michael G. A1 - Powe, Neil A1 - Hwang, Shih-Jen A1 - Dehghan, Abbas A1 - Rivadeneira, Fernando A1 - Uitterlinden, André A1 - Hofman, Albert A1 - Beckmann, Jacques S. A1 - Krämer, Bernhard K. A1 - Witteman, Jacqueline A1 - Bochud, Murielle A1 - Siscovick, David A1 - Rettig, Rainer A1 - Kronenberg, Florian A1 - Wanner, Christoph A1 - Thadhani, Ravi I. A1 - Heid, Iris M. A1 - Fox, Caroline S. A1 - Kao, W.H. T1 - Association of eGFR-Related Loci Identified by GWAS with Incident CKD and ESRD JF - PLoS Genetics N2 - Family studies suggest a genetic component to the etiology of chronic kidney disease (CKD) and end stage renal disease (ESRD). Previously, we identified 16 loci for eGFR in genome-wide association studies, but the associations of these single nucleotide polymorphisms (SNPs) for incident CKD or ESRD are unknown. We thus investigated the association of these loci with incident CKD in 26,308 individuals of European ancestry free of CKD at baseline drawn from eight population-based cohorts followed for a median of 7.2 years (including 2,122 incident CKD cases defined as eGFR < 60ml/min/1.73m(2) at follow-up) and with ESRD in four case-control studies in subjects of European ancestry (3,775 cases, 4,577 controls). SNPs at 11 of the 16 loci (UMOD, PRKAG2, ANXA9, DAB2, SHROOM3, DACH1, STC1, SLC34A1, ALMS1/NAT8, UBE2Q2, and GCKR) were associated with incident CKD; p-values ranged from p = 4.1e-9 in UMOD to p = 0.03 in GCKR. After adjusting for baseline eGFR, six of these loci remained significantly associated with incident CKD (UMOD, PRKAG2, ANXA9, DAB2, DACH1, and STC1). SNPs in UMOD (OR = 0.92, p = 0.04) and GCKR (OR = 0.93, p = 0.03) were nominally associated with ESRD. In summary, the majority of eGFR-related loci are either associated or show a strong trend towards association with incident CKD, but have modest associations with ESRD in individuals of European descent. Additional work is required to characterize the association of genetic determinants of CKD and ESRD at different stages of disease progression. KW - Chronic Kidney-disease KW - Stage renal-disease KW - Glomerular-filtration-rate KW - Diabetic-nephropathy KW - General-population KW - African-americans KW - Risk KW - Progression KW - Mortality KW - Variants Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133758 VL - 7 IS - 9 ER - TY - JOUR A1 - Chapdelaine, Isabelle A1 - de Roij van Zuijdewijn, Camiel L.M. A1 - Mostovaya, Ira M. A1 - Lévesque, Renée A1 - Davenport, Andrew A1 - Blankestijn, Peter J. A1 - Wanner, Christoph A1 - Nubé, Menso J. A1 - Grooteman, Muriel P.C. T1 - Optimization of the convection volume in online post-dilution haemodiafiltration: practical and technical issues JF - Clinical Kidney Journal N2 - In post-dilution online haemodiafiltration (ol-HDF), a relationship has been demonstrated between the magnitude of the convection volume and survival. However, to achieve high convection volumes (>22 L per session) detailed notion of its determining factors is highly desirable. This manuscript summarizes practical problems and pitfalls that were encountered during the quest for high convection volumes. Specifically, it addresses issues such as type of vascular access, needles, blood flow rate, recirculation, filtration fraction, anticoagulation and dialysers. Finally, five of the main HDF systems in Europe are briefly described as far as HDF prescription and optimization of the convection volume is concerned. KW - convection volume KW - haemodiafiltration KW - dialysis Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-150020 VL - 8 IS - 2 ER - TY - JOUR A1 - Dannewitz, Bettina A1 - Sommerer, Claudia A1 - Stölzel, Peggy A1 - Baid‐Agrawal, Seema A1 - Nadal, Jennifer A1 - Bärthlein, Barbara A1 - Wanner, Christoph A1 - Eckardt, Kai‐Uwe A1 - Zeier, Martin A1 - Schlagenhauf, Ulrich A1 - Krane, Vera A1 - Jockel‐Schneider, Yvonne T1 - Status of periodontal health in German patients suffering from chronic kidney disease—Data from the GCKD study JF - Journal of Clinical Periodontology N2 - Aim To assess the prevalence and severity of periodontitis in patients with moderate chronic kidney disease (CKD) and comparing the results with the self‐reported periodontitis awareness of the study subjects. Material and methods The periodontal status of 270 patients with moderate CKD randomly selected from a cohort of 5,217 subjects participating in the prospective observational German Chronic Kidney Disease (GCKD) project was analysed by recording bleeding on probing (BOP), probing pocket depth (PPD) and clinical attachment level (CAL). Furthermore, the awareness of the study subjects of their periodontal conditions was evaluated by a self‐reported questionnaire. Results 24.4% of the CKD study patients showed no or only mild signs of periodontal disease, 47.6% displayed moderate and 27% severe periodontitis. Questionnaire data revealed that 62.3% of the study subjects with severe periodontitis were not aware of the presence of the disease, 44.4% denied having received any systematic periodontal therapy so far, although 50% of them indicated to visit their dentist regularly for professional tooth cleanings. Conclusion While the clinical study data confirm an increased prevalence of periodontitis in CKD patients, their self‐reported awareness of periodontitis was low. KW - chronic kidney disease KW - observational cohort study KW - periodontitis KW - risk factors Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-217821 VL - 47 IS - 1 SP - 19 EP - 29 ER - TY - JOUR A1 - de Zeeuw, Dick A1 - Akizawa, Tadao A1 - Agarwal, Rajiv A1 - Audhya, Paul A1 - Bakris, George L. A1 - Chin, Melanie A1 - Krauth, Melissa A1 - Lambers Heerspink, Hiddo J. A1 - Meyer, Colin J. A1 - McMurray, John J. A1 - Parving, Hans-Henrik A1 - Pergola, Pablo E. A1 - Remuzzi, Giuseppe A1 - Toto, Robert D. A1 - Vaziri, Nosratola D. A1 - Wanner, Christoph A1 - Warnock, David G. A1 - Wittes, Janet A1 - Chertow, Glenn M. T1 - Rationale and Trial Design of Bardoxolone Methyl Evaluation in Patients with Chronic Kidney Disease and Type 2 Diabetes: The Occurrence of Renal Events (BEACON) JF - American Journal of Nephrology N2 - Background: Chronic kidney disease (CKD) associated with type 2 diabetes mellitus constitutes a global epidemic complicated by considerable renal and cardiovascular morbidity and mortality, despite the provision of inhibitors of the renin-angiotensin-aldosterone system (RAAS). Bardoxolone methyl, a synthetic triterpenoid that reduces oxidative stress and inflammation through Nrf2 activation and inhibition of NF-κB was previously shown to increase estimated glomerular filtration rate (eGFR) in patients with CKD associated with type 2 diabetes mellitus. To date, no antioxidant or anti-inflammatory therapy has proved successful at slowing the progression of CKD. Methods: Herein, we describe the design of Bardoxolone Methyl Evaluation in Patients with Chronic Kidney Disease and Type 2 Diabetes: the Occurrence of Renal Events (BEACON) trial, a multinational, multicenter, double-blind, randomized, placebo-controlled Phase 3 trial designed to determine whether long-term administration of bardoxolone methyl (on a background of standard therapy, including RAAS inhibitors) safely reduces renal and cardiac morbidity and mortality. Results: The primary composite endpoint is time-to-first occurrence of either end-stage renal disease or cardiovascular death. Secondary endpoints include the change in eGFR and time to occurrence of cardiovascular events. Conclusion: BEACON will be the first event-driven trial to evaluate the effect of an oral antioxidant and anti-inflammatory drug in advanced CKD. KW - clinical trial KW - diabetes mellitus KW - glomerular filtration rate KW - trial design KW - bardoxolone methyl KW - Nrf2 KW - end-stage renal disease KW - cardiovascular death KW - chronic kidney disease Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196832 SN - 0250-8095 SN - 1421-9670 N1 - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively. VL - 37 IS - 3 ER - TY - JOUR A1 - Dienemann, Thomas A1 - Fujii, Naohiko A1 - Orlandi, Paula A1 - Nessel, Lisa A1 - Furth, Susan L. A1 - Hoy, Wendy E. A1 - Matsuo, Seiichi A1 - Mayer, Gert A1 - Methven, Shona A1 - Schaefer, Franz A1 - Schaeffner, Elke S. A1 - Solá, Laura A1 - Stengel, Bénédicte A1 - Wanner, Christoph A1 - Zhang, Luxia A1 - Levin, Adeera A1 - Eckardt, Kai-Uwe A1 - Feldman, Harold I. T1 - International Network of Chronic Kidney Disease cohort studies (iNET-CKD): a global network of chronic kidney disease cohorts JF - BMC Nephrology N2 - Background Chronic kidney disease (CKD) is a global health burden, yet it is still underrepresented within public health agendas in many countries. Studies focusing on the natural history of CKD are challenging to design and conduct, because of the long time-course of disease progression, a wide variation in etiologies, and a large amount of clinical variability among individuals with CKD. With the difference in health-related behaviors, healthcare delivery, genetics, and environmental exposures, this variability is greater across countries than within one locale and may not be captured effectively in a single study. Methods Studies were invited to join the network. Prerequisites for membership included: 1) observational designs with a priori hypotheses and defined study objectives, patient-level information, prospective data acquisition and collection of bio-samples, all focused on predialysis CKD patients; 2) target sample sizes of 1,000 patients for adult cohorts and 300 for pediatric cohorts; and 3) minimum follow-up of three years. Participating studies were surveyed regarding design, data, and biosample resources. Results Twelve prospective cohort studies and two registries covering 21 countries were included. Participants age ranges from >2 to >70 years at inclusion, CKD severity ranges from stage 2 to stage 5. Patient data and biosamples (not available in the registry studies) are measured yearly or biennially. Many studies included multiple ethnicities; cohort size ranges from 400 to more than 13,000 participants. Studies’ areas of emphasis all include but are not limited to renal outcomes, such as progression to ESRD and death. Conclusions iNET-CKD (International Network of CKD cohort studies) was established, to promote collaborative research, foster exchange of expertise, and create opportunities for research training. Participating studies have many commonalities that will facilitate comparative research; however, we also observed substantial differences. The diversity we observed across studies within this network will be able to be leveraged to identify genetic, behavioral, and health services factors associated with the course of CKD. With an emerging infrastructure to facilitate interactions among the investigators of iNET-CKD and a broadly defined research agenda, we are confident that there will be great opportunity for productive collaborative investigations involving cohorts of individuals with CKD. KW - Cohort study KW - Network KW - CKD KW - Epidemiology KW - Diversity Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164604 VL - 17 ER - TY - JOUR A1 - Drechsler, Christiane A1 - Kolleritz, Barbara A1 - Meinitzer, Andreas A1 - März, Winfried A1 - Ritz, Eberhard A1 - König, Paul A1 - Neyer, Ulrich A1 - Pilz, Stefan A1 - Wanner, Christoph A1 - Kronenberg, Florian T1 - Homoarginine and Progression of Chronic Kidney Disease: Results from the Mild to Moderate Kidney Disease Study JF - PLoS ONE N2 - Background: Homoarginine is an amino acid derivative mainly synthesized in the kidney. It is suggested to increase nitric oxide availability, enhance endothelial function and to protect against cardiovascular diseases. We aimed to investigate the relation between homoarginine, kidney function and progression of chronic kidney disease (CKD). Methods: We measured plasma homoarginine concentrations in baseline samples of the Mild to Moderate Kidney Disease (MMKD) Study, a prospective cohort study of 227 patients with CKD in Europe. Homoarginine concentrations were available in 182 of the baseline samples and in 139 of the prospectively-followed patients. We correlated homoarginine concentrations to parameters of kidney function. The association between homoarginine and progression of CKD was assessed during a follow-up of up to seven years (median 4.45 years, interquartile range 2.54-5.19) using Cox regression analysis. Progression of CKD was defined as doubling of baseline serum creatinine and/or end-stage renal disease. Results: Study participants were at baseline on average 47 \(\pm\)13 years old and 65% were male. Mean \(\pm\) standard deviation of homoarginine concentrations were \(2.5 \pm 1.1 \mu mol/L\) and concentrations were incrementally lower at lower levels of GFR with mean concentrations of \(2.90 \pm 1.02 \mu mol/L\) (GFR. 90 ml/min), \(2.64 \pm 1.06 \mu mol/L\) (GFR 60-90 ml/min), \(2.52 \pm 1.24 \mu mol/L\) (GFR 30-60 ml/min) and \(2.05 \pm 0.78 \mu mol/L\) (GFR, 30 ml/min), respectively (p = 0.002). The age-and sex-adjusted risk to reach the renal endpoint was significantly higher by 62% with each decrease by one standard deviation (\(1.1 \mu mol/L\)) of homoarginine (HR 1.62, 95% CI 1.16-2.27, p = 0.005). This association was independent of proteinuria (HR 1.56, 95% CI 1.11-2.20, p = 0.01), and was slightly attenuated when adjusting for GFR (HR 1.40 (95% CI 0.98-1.98, p = 0.06). Conclusions: Homoarginine concentrations are directly correlated with kidney function and are significantly associated with the progression of CKD. Low homoarginine concentrations might be an early indicator of kidney failure and a potential target for the prevention of disease progression which needs further investigations. KW - risk KW - alkaline phosphatase KW - cardiovascular events KW - nictric-oxide KW - induced insulin-release KW - creatine synthesis KW - renal function KW - heart failure KW - rat kidney KW - L-arginine Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130979 VL - 8 IS - 5 ER -