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Ibrahim ST, Chinnadurai R, Ali I, Payne D, Rice GI, Newman WG, Algohary E, Adam AG, Kalra PA. Genetic polymorphism in C3 is associated with progression in chronic kidney disease (CKD) patients with IgA nephropathy but not in other causes of CKD. PLoS One 2020; 15:e0228101. [PMID: 32004338 PMCID: PMC6994105 DOI: 10.1371/journal.pone.0228101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 01/07/2020] [Indexed: 12/14/2022] Open
Abstract
Objectives The R102G variant in complement 3 (C3) results in two allotypic variants: C3 fast (C3F) and C3 slow (C3S). C3F presents at increased frequency in patients with chronic kidney disease (CKD), our aim is to explore its role in CKD progression and mortality. Methods Delta (Δ) eGFR for 2038 patients in the Salford Kidney Study (SKS) was calculated by linear regression; those with ≤-3ml/min/1.73m2/yr were defined as rapid progressors (RP) and those with ΔeGFR between -0.5 and +1ml/min/1.73m2/yr, labelled stable CKD patients (SP).A group of 454 volunteers was used as a control group. In addition, all biopsy-proven glomerulonephritis (GN) patients were studied regardless of their ΔeGFR. R102G was analysed by real-time PCR, and genotypic and allelic frequencies were compared between RP and SP along with the healthy control group. Results There were 255 SP and 259 RP in the final cohort. Median ΔeGFR was 0.07 vs. -4.7 ml/min/1.73m2/yr in SP vs. RP. C3F allele frequency was found to be significantly higher in our CKD cohort (25.7%) compared with the healthy control group (20.6%); p = 0.008.However, there was no significant difference in C3F allele frequency between the RP and SP groups. In a subgroup analysis of 37 patients with IgA nephropathy in the CKD cohort (21 RP and 16 SP), there was a significantly higher frequency of C3F in RP 40.5% vs. 9.4% in SP; p = 0.003. In the GN group, Cox regression showed an association between C3F and progression only in those with IgA nephropathy (n = 114);HR = 1.9 (95% CI 1.1–3.1; p = 0.018) for individuals heterozygous for the C3F variant, increased further for individuals homozygous for the variant, HR = 2.8 (95% CI 1.2–6.2; p = 0.014). Conclusion The C3 variant R102G is associated with progression of CKD in patients with IgA nephropathy.
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Affiliation(s)
- Sara T. Ibrahim
- Department of Internal Medicine and Nephrology, Faculty of Medicine, Alexandria University, Alexandria, Egypt
- Department of Renal Medicine, Salford Royal NHS Foundation Trust, Salford, United Kingdom
- University of Manchester, Manchester, United Kingdom
- * E-mail:
| | - Rajkumar Chinnadurai
- Department of Renal Medicine, Salford Royal NHS Foundation Trust, Salford, United Kingdom
- University of Manchester, Manchester, United Kingdom
| | - Ibrahim Ali
- Department of Renal Medicine, Salford Royal NHS Foundation Trust, Salford, United Kingdom
- University of Manchester, Manchester, United Kingdom
| | - Debbie Payne
- University of Manchester, Manchester, United Kingdom
| | - Gillian I. Rice
- Manchester Centre for Genomic Medicine, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, United Kingdom
| | - William G. Newman
- Division of Evolution and Genomic Sciences, Faculty of Biology, Medicine and Human Sciences, University of Manchester, Manchester, United Kingdom
| | - Eman Algohary
- Department of Internal Medicine and Nephrology, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | - Ahmed G. Adam
- Department of Internal Medicine and Nephrology, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | - Philip A. Kalra
- Department of Renal Medicine, Salford Royal NHS Foundation Trust, Salford, United Kingdom
- University of Manchester, Manchester, United Kingdom
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Törmänen S, Pörsti I, Lakkisto P, Tikkanen I, Niemelä O, Paavonen T, Mustonen J, Eräranta A. Endothelin A receptor blocker and calcimimetic in the adenine rat model of chronic renal insufficiency. BMC Nephrol 2017; 18:323. [PMID: 29078759 PMCID: PMC5659028 DOI: 10.1186/s12882-017-0742-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 10/17/2017] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND We studied whether endothelin receptor antagonist and calcimimetic treatments influence renal damage and kidney renin-angiotensin (RA) components in adenine-induced chronic renal insufficiency (CRI). METHODS Male Wistar rats (n = 80) were divided into 5 groups for 12 weeks: control (n = 12), 0.3% adenine (Ade; n = 20), Ade + 50 mg/kg/day sitaxentan (n = 16), Ade + 20 mg/kg/day cinacalcet (n = 16), and Ade + sitaxentan + cinacalcet (n = 16). Blood pressure (BP) was measured using tail-cuff, kidney histology was examined, and RA components measured using RT-qPCR. RESULTS Adenine caused tubulointerstitial damage with severe CRI, anemia, hyperphosphatemia, 1.8-fold increase in urinary calcium excretion, and 3.5-fold and 18-fold increases in plasma creatinine and PTH, respectively. Sitaxentan alleviated tubular atrophy, while sitaxentan + cinacalcet combination reduced interstitial inflammation, tubular dilatation and atrophy in adenine-rats. Adenine diet did not influence kidney angiotensin converting enzyme (ACE) and AT4 receptor mRNA, but reduced mRNA of renin, AT1a, AT2, (pro)renin receptor and Mas to 40-60%, and suppressed ACE2 to 6% of that in controls. Sitaxentan reduced BP by 8 mmHg, creatinine, urea, and phosphate concentrations by 16-24%, and PTH by 42%. Cinacalcet did not influence BP or creatinine, but reduced PTH by 84%, and increased hemoglobin by 28% in adenine-rats. The treatments further reduced renin mRNA by 40%, while combined treatment normalized plasma PTH, urinary calcium, and increased ACE2 mRNA 2.5-fold versus the Ade group (p < 0.001). CONCLUSIONS In adenine-induced interstitial nephritis, sitaxentan improved renal function and tubular atrophy. Sitaxentan and cinacalcet reduced kidney renin mRNA by 40%, while their combination alleviated tubulointerstitial damage and urinary calcium loss, and increased kidney tissue ACE2 mRNA.
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Affiliation(s)
- Suvi Törmänen
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland
| | - Ilkka Pörsti
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland. .,Department of Internal Medicine, Tampere University Hospital, Tampere, Finland. .,School of Medicine / Internal Medicine, FIN-33014 University of Tampere, Tampere, Finland.
| | - Päivi Lakkisto
- Minerva Institute for Medical Research, Helsinki, Finland.,Clinical Chemistry and Hematology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Ilkka Tikkanen
- Minerva Institute for Medical Research, Helsinki, Finland.,Abdominal Center, Nephrology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Onni Niemelä
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland.,Medical Research Unit, Seinäjoki Central Hospital, Seinäjoki, Finland
| | - Timo Paavonen
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland.,Fimlab Laboratories, Tampere, Finland
| | - Jukka Mustonen
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland.,Department of Internal Medicine, Tampere University Hospital, Tampere, Finland
| | - Arttu Eräranta
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland
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Han N, Hong SH, Kim YS, Kim DK, Kim IW, Ji E, Oh JM. Effect of additive calcium administration on FGF23 levels in patients with mild chronic kidney disease treated with calcitriol: a randomized, open-labeled clinical trial. Ther Clin Risk Manag 2017; 13:999-1007. [PMID: 28860784 PMCID: PMC5565373 DOI: 10.2147/tcrm.s142564] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND The purpose of the present study was to determine the effect of additional calcium carbonate treatment on fibroblast growth factor 23 (FGF23) levels in patients treated with calcitriol. METHODS In this randomized, open-labeled, and parallel-group study, a total of 30 patients with early chronic kidney disease (CKD) and vitamin D deficiency were randomly assigned to two groups and received interventions for 8 weeks: 1) a combination of calcium carbonate and calcitriol group; and 2) calcitriol only group. The primary outcome was the difference in percentage change of serum FGF23 levels from baseline between the two groups. Secondary end points included the changes in serum levels of calcium, phosphate, parathyroid hormone (PTH), and 25-hydroxyvitamin D3 (25(OH)D) from baseline. RESULTS Serum FGF23 levels were more elevated in the combination group than in the calcitriol-alone group. However, both mean change and percentage change in the serum FGF23 levels during the 8-week period were not significantly different between the two groups. Serum calcium level was increased significantly only in the combination treatment group. There was no significant difference in percentage change of serum calcium levels between the two groups. In addition, changes in serum levels of phosphate, 25(OH)D, or PTH were not significantly different between the two groups. In correlation analysis, changes in serum FGF23 levels were positively correlated with changes in serum calcium and phosphate levels, but not with changes in 25(OH)D or PTH levels. No serious adverse events were observed, however, there was one case of mild gastrointestinal discomfort. CONCLUSION This study revealed that additional calcium carbonate treatment significantly increased serum FGF23 levels in patients treated with calcitriol, with their synergistic effect in promoting intestinal calcium absorption. This suggests that serum FGF23 levels should be monitored regularly, especially in those who use combination of vitamin D and calcium carbonate from the early stages of CKD.
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Affiliation(s)
- Nayoung Han
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul
| | - Su Hyun Hong
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul.,Pharmaceutical Standardization Division, Drug Evaluation Department, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do
| | - Yon Su Kim
- Division of Nephrology, Department of Internal Medicine, Seoul National University Hospital, Seoul
| | - Dong Ki Kim
- Division of Nephrology, Department of Internal Medicine, Seoul National University Hospital, Seoul
| | - In-Wha Kim
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul
| | - Eunhee Ji
- College of Pharmacy, Gachon University, Incheon, Republic of Korea
| | - Jung Mi Oh
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul
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Protein Array-Based Detection of Proteins in Kidney Tissues from Patients with Membranous Nephropathy. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7843584. [PMID: 28337458 PMCID: PMC5350302 DOI: 10.1155/2017/7843584] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Revised: 01/25/2017] [Accepted: 01/29/2017] [Indexed: 11/26/2022]
Abstract
Membranous nephropathy (MN) is an autoimmune inflammatory disease in which proteins related with plenty of biological processes play an important role. However, the role of these proteins in the pathogenesis of MN is still unclear. This study aimed to screen differential proteins in kidney tissue samples from MN patients by using protein arrays and determine the pathways involved in the pathogenesis of MN. This study first tested a quantitative protein array (QAH-INF-3) and two semiquantitative protein arrays (L-493 and L-507) with normal renal tissue and identified L-493 as the most appropriate assay to compare protein levels between MN tissues and normal control tissues. The L-493 array identified 66 differentially expressed proteins (DEPs) that may be associated with MN. The gene oncology (GO) and protein-protein interaction (PPI) analyses revealed several processes potentially involved in MN, including extracellular matrix disassembly and organization, cell adhesion, cell-cell signaling, cellular protein metabolic process, and immune response (P < 0.05). We suggest that these different pathways work together via protein signaling and result in the pathogenesis and progression of MN.
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Wasser WG, Gil A, Skorecki KL. The Envy of Scholars: Applying the Lessons of the Framingham Heart Study to the Prevention of Chronic Kidney Disease. Rambam Maimonides Med J 2015; 6:RMMJ.10214. [PMID: 26241225 PMCID: PMC4524402 DOI: 10.5041/rmmj.10214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
During the past 50 years, a dramatic reduction in the mortality rate associated with cardiovascular disease has occurred in the US and other countries. Statistical modeling has revealed that approximately half of this reduction is the result of risk factor mitigation. The successful identification of such risk factors was pioneered and has continued with the Framingham Heart Study, which began in 1949 as a project of the US National Heart Institute (now part of the National Heart, Lung, and Blood Institute). Decreases in total cholesterol, blood pressure, smoking, and physical inactivity account for 24%, 20%, 12%, and 5% reductions in the mortality rate, respectively. Nephrology was designated as a recognized medical professional specialty a few years later. Hemodialysis was first performed in 1943. The US Medicare End-Stage Renal Disease (ESRD) Program was established in 1972. The number of patients in the program increased from 5,000 in the first year to more than 500,000 in recent years. Only recently have efforts for risk factor identification, early diagnosis, and prevention of chronic kidney disease (CKD) been undertaken. By applying the approach of the Framingham Heart Study to address CKD risk factors, we hope to mirror the success of cardiology; we aim to prevent progression to ESRD and to avoid the cardiovascular complications associated with CKD. In this paper, we present conceptual examples of risk factor modification for CKD, in the setting of this historical framework.
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Affiliation(s)
- Walter G. Wasser
- Division of Nephrology, Mayanei HaYeshua Medical Center, Bnei Brak, Israel
- Division of Nephrology, Rambam Health Care Campus, Haifa, Israel
- To whom correspondence should be addressed. E-mail:
| | - Amnon Gil
- Division of Nephrology, Carmel Medical Center, Haifa, Israel
| | - Karl L. Skorecki
- Division of Nephrology, Rambam Health Care Campus, Haifa, Israel
- Ruth & Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
- Director of Medical and Research Development, Rambam Health Care Campus, Haifa, Israel
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Di Iorio B, Di Micco L, Torraca S, Sirico ML, Russo L, Pota A, Mirenghi F, Russo D. Acute Effects of Very-Low-Protein Diet on FGF23 Levels: A Randomized Study. Clin J Am Soc Nephrol 2012; 7:581-7. [DOI: 10.2215/cjn.07640711] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Abstract
The kidney is the major, if not sole, site for the production of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3), the biologically active form of vitamin D that can stimulate calcium reabsorption in the kidney and may provide renoprotective benefits. The biological effects of 1,25(OH)2D3 are mediated through a nuclear hormone receptor, known as the vitamin D receptor (VDR). It is well accepted that the VDR is present in the distal renal convoluted tubule cells; however, whether VDR is present in other kidney cell types is uncertain. Using a highly specific and sensitive anti-VDR antibody, we determined its distribution in the mouse kidney by immunohistochemistry. Our results show that the VDR is not only present in the distal but is also found in the proximal tubules, but at 24-fold lower levels. The VDR was also found in the macula densa of the juxtaglomerular apparatus, glomerular parietal epithelial cells, and podocytes. In contrast, the VDR is either very low or absent in interstitial fibroblasts, glomerular mesangial cells, and juxtaglomerular cells. Thus, identification of VDR in the proximal tubule, macula densa, and podocytes suggests that 1,25(OH)2D3 plays a direct role in these cells under normal conditions.
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Abstract
PURPOSE OF REVIEW The present review provides an overview of the identified risk factors for chronic kidney disease (CKD) progression emphasizing the pediatric population. RECENT FINDINGS Over the past 10 years, there have been significant changes to our understanding and study of preterminal kidney failure. Recent refinements in the measurement of glomerular filtration rate and glomerular filtration rate estimating equations are important tools for identification and association of risk factors for CKD progression in children. In pediatric CKD, lower level of kidney function at presentation, higher levels of proteinuria, and hypertension are known markers for a more rapid decline in glomerular filtration rate. Anemia and other reported risk factors from the pregenomic era require further study and validation. Genome-wide association studies have identified genetic loci that have provided novel genetic risk factors for CKD progression. SUMMARY With cohort studies of children with CKD becoming mature, they have started to yield important refinements to the assessment of CKD progression. Although many of the traditional risk factors for renal progression will certainly be assessed, such cohorts will be important for evaluating novel risk factors identified by genome-wide studies.
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Abstract
PURPOSE OF REVIEW Childhood chronic kidney disease usually progresses towards end-stage renal failure once a critical impairment of renal function has occurred. This process is largely independent of the underlying renal disease. Recent clinical trials have provided evidence that the progressive course of chronic kidney disease can be slowed substantially by pharmacological intervention. RECENT FINDINGS Hypertension and proteinuria are the most important independent risk factors for renal disease progression in both adult and pediatric nephropathies. Pharmacological blockade of the renin-angiotensin system provides efficient control of blood pressure and proteinuria, and superior long-term renoprotection compared with other antihypertensive agents. Recent pediatric evidence supports the renoprotective efficacy of tight blood pressure control aiming for the low-normal range. In addition, promising preliminary findings suggest an additional renoprotective potential by correction of metabolic acidosis and hyperuricemia and by administration of antiproliferative and antioxidative drugs. SUMMARY Pharmacological renoprotection currently focuses on antihypertensive and antiproteinuric treatment by blockade of the renin-angiotensin system. Intensified blood pressure control can improve 5-year renal survival by 35% in children with chronic kidney disease. Additional complementary strategies under current clinical evaluation bear potential to improve renal survival even further.
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Kronenberg F. Emerging risk factors and markers of chronic kidney disease progression. Nat Rev Nephrol 2010; 5:677-89. [PMID: 19935815 DOI: 10.1038/nrneph.2009.173] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Chronic kidney disease (CKD) is a common condition with an increasing prevalence. A number of comorbidities are associated with CKD and prognosis is poor, with many patients experiencing disease progression. Recognizing the factors associated with CKD progression enables high-risk patients to be identified and given more intensive treatment if necessary. The identification of new predictive markers might improve our understanding of the pathogenesis and progression of CKD. This Review discusses a number of emerging factors and markers for which epidemiological evidence from prospective studies indicates an association with progression of CKD. The following factors and markers are discussed: asymmetric dimethylarginine, factors involved in calcium-phosphate metabolism, adrenomedullin, A-type natriuretic peptide, N-terminal pro-brain natriuretic peptide, liver-type fatty acid binding protein, kidney injury molecule 1, neutrophil gelatinase-associated lipocalin, apolipoprotein A-IV, adiponectin and some recently identified genetic polymorphisms. Additional epidemiological and experimental data are required before these markers can be broadly used for the prediction of CKD progression and before the risk factors can be considered as potential drug targets in clinical interventional trials.
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Affiliation(s)
- Florian Kronenberg
- Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Innsbruck, Austria.
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Jepson RE, Brodbelt D, Vallance C, Syme HM, Elliott J. Evaluation of predictors of the development of azotemia in cats. J Vet Intern Med 2009; 23:806-13. [PMID: 19566846 DOI: 10.1111/j.1939-1676.2009.0339.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Chronic kidney disease (CKD) is a common condition in geriatric cats. Diagnosis is based on the development of persistent azotemia with inadequate urine concentrating ability. Biomarkers are sought for early identification. HYPOTHESIS Clinical variables, urine concentrating ability, proteinuria, and N-acetyl-beta-D-glucosaminidase (NAG) index will be predictive of cats at risk of developing azotemia within 12 months. ANIMALS Client-owned nonazotemic geriatric (>or=9 years) cats. METHODS Prospective longitudinal cohort study monitoring a population of healthy nonazotemic geriatric cats every 6 months until development of azotemia, death, or the study end point (September 30, 2007). Multivariable logistic regression analysis was used to assess baseline clinical, biochemical, and urinalysis variables, urine protein to creatinine ratio (UP/C), urine albumin to creatinine (UA/C) ratio, and urinary NAG index as predictors of development of azotemia. RESULTS One hundred and eighteen cats were recruited with a median age of 13 years. Ninety-five cats (80.5%) had been followed or reached the study end point by 12 months of which 30.5% (29/95) developed azotemia. Age, systolic blood pressure, plasma creatinine concentration, urine specific gravity, UP/C, UA/C, and NAG index were significantly associated with development of azotemia in the univariable analysis (P<or=.05). However, in the multivariable analysis, only plasma creatinine concentration with either UP/C (Model 1) or UA/C (Model 2) remained significant. CONCLUSIONS AND CLINICAL IMPORTANCE This study demonstrates a high incidence of azotemia in a population of previously healthy geriatric cats. Proteinuria at presentation was significantly associated with development of azotemia although causal association cannot be inferred. Evaluation of NAG index offered no additional benefit.
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Affiliation(s)
- R E Jepson
- Department of Veterinary Basic Science, Royal Veterinary College, Royal College Street, Camden, London, USA.
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Shinaberger CS, Greenland S, Kopple JD, Van Wyck D, Mehrotra R, Kovesdy CP, Kalantar-Zadeh K. Is controlling phosphorus by decreasing dietary protein intake beneficial or harmful in persons with chronic kidney disease? Am J Clin Nutr 2008; 88:1511-8. [PMID: 19064510 PMCID: PMC5500249 DOI: 10.3945/ajcn.2008.26665] [Citation(s) in RCA: 228] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Dietary restrictions to control serum phosphorus, which are routinely recommended to persons with chronic kidney disease, are usually associated with a reduction in protein intake. This may lead to protein-energy wasting and poor survival. OBJECTIVE We aimed to ascertain whether a decline in serum phosphorus and a concomitant decline in protein intake are associated with an increase in the risk of death. DESIGN In a 3-y study (7/2001-6/2004) of 30 075 prevalent maintenance hemodialysis (MHD) patients, we examined changes in serum phosphorus and in normalized protein nitrogen appearance (nPNA), a surrogate of dietary protein intake, during the first 6 mo and the subsequent mortality. Four groups of MHD patients were defined on the basis of the direction of the changes in serum phosphorus and nPNA. RESULTS Baseline phosphorus had a J-shaped association with mortality, whereas higher baseline nPNA was linearly associated with greater survival. Compared with MHD patients whose serum phosphorus and nPNA both rose over 6 mo, those whose serum phosphorus decreased but whose nPNA increased had greater survival, with a case mix-adjusted death risk ratio of 0.90 (95% confidence limits: 0.86, 0.95; P < 0.001), whereas those whose phosphorus increased but whose nPNA decreased or those whose phosphorus and nPNA both decreased had worse mortality with a risk ratio of 1.11 (1.05,1.17; P < 0.001) and 1.06 (1.01,1.12; P = 0.02), respectively. CONCLUSIONS The risk of controlling serum phosphorus by restricting dietary protein intake may outweigh the benefit of controlled phosphorus and may lead to greater mortality. Additional studies including randomized controlled trials should examine whether nondietary control of phosphorus or restriction of nonprotein sources of phosphorus is safer and more effective.
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Affiliation(s)
- Christian S Shinaberger
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA 90509-2910, USA
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Kovesdy CP, Kalantar-Zadeh K. Bone and mineral disorders in pre-dialysis CKD. Int Urol Nephrol 2008; 40:427-40. [PMID: 18368510 DOI: 10.1007/s11255-008-9346-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Accepted: 01/29/2008] [Indexed: 11/28/2022]
Abstract
Disorders in calcium, phosphorus, and parathyroid hormone (PTH) are common in chronic kidney disease (CKD) and may be associated with poor outcomes including a higher rate of CKD progression and increased death risk. Although these abnormalities have been examined extensively in patients with CKD stage 5 who are receiving chronic maintenance dialysis, they have not been studied to the same extent at earlier stages of CKD, in spite of the much larger numbers of patients in the early CKD population. We summarize the available literature on outcomes associated with bone and mineral disorders in patients with CKD not yet receiving maintenance dialysis. We have reviewed novel data linking fibroblast growth factor 23 (FGF-23) to phosphorus and vitamin D homeostasis. More rapid CKD progression is linked to hyperphosphatemia and its associated hyperparathyroidism and vitamin D deficiency. Hence, hyperphosphatemia may play a central role in the diverse disorders characterizing CKD. We provide a brief overview of the available treatment recommendations for bone and mineral disorders, with an emphasis on areas needing further research.
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Affiliation(s)
- Csaba P Kovesdy
- Division of Nephrology, Salem VA Medical Center, 1970 Roanoke Boulevard, Salem, VA 24153, USA.
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Wühl E, Schaefer F. Therapeutic strategies to slow chronic kidney disease progression. Pediatr Nephrol 2008; 23:705-16. [PMID: 18335252 PMCID: PMC2275772 DOI: 10.1007/s00467-008-0789-y] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Revised: 02/05/2008] [Accepted: 02/06/2008] [Indexed: 12/30/2022]
Abstract
Childhood chronic kidney disease commonly progresses toward end-stage renal failure, largely independent of the underlying disorder, once a critical impairment of renal function has occurred. Hypertension and proteinuria are the most important independent risk factors for renal disease progression. Therefore, current therapeutic strategies to prevent progression aim at controlling blood pressure and reducing urinary protein excretion. Renin-angiotensin-system (RAS) antagonists preserve kidney function not only by lowering blood pressure but also by their antiproteinuric, antifibrotic, and anti-inflammatory properties. Intensified blood pressure control, probably aiming for a target blood pressure below the 75th percentile, may exert additional renoprotective effects. Other factors contributing in a multifactorial manner to renal disease progression include dyslipidemia, anemia, and disorders of mineral metabolism. Measures to preserve renal function should therefore also comprise the maintenance of hemoglobin, serum lipid, and calcium-phosphorus ion product levels in the normal range.
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Affiliation(s)
- Elke Wühl
- Division of Pediatric Nephrology, University Hospital Heidelberg for Pediatric and Adolescent Medicine, Im Neuenheimer Feld 151, Heidelberg, Germany.
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Abstract
Hyperphosphatemia is a characteristic complication of significant chronic kidney disease. Elevated serum phosphorous is associated with reduced survival. Hyperphosphatemia has long been recognized as predisposing to uremic bone disease and disorders of parathyroid function. Furthermore, elevated serum phosphate has been implicated particularly in the development of cardiovascular structural and functional abnormalities. Given the limitations of restricting phosphate in the diet and the inadequate removal by conventional dialysis regimes, nephrologists rely on the use of additional medications to control serum levels (currently oral phosphate binders). This review focuses on new agents and therapeutic approaches dealing with hyperphosphatemia in chronic kidney disease, that are not currently licensed and available in routine clinical practise. This article attempts to review therapies under development and considers additional effects that the next generation of agents may bring over and above those already within the therapeutic armamentarium.
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Affiliation(s)
- Christopher W McIntyre
- Division of Vascular Medicine, School of Medical & Surgical Sciences, University of Nottingham Medical School at Derby, Derby, United Kingdom.
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