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Pérez-Aizpurua X, Cabello Benavente R, Bueno Serrano G, Alcázar Peral JM, Gómez-Jordana Mañas B, Tufet i Jaumot J, Ruiz de Castroviejo Blanco J, Osorio Ospina F, Gonzalez-Enguita C. Obstructive uropathy: Overview of the pathogenesis, etiology and management of a prevalent cause of acute kidney injury. World J Nephrol 2024; 13:93322. [PMID: 38983763 PMCID: PMC11229834 DOI: 10.5527/wjn.v13.i2.93322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 05/24/2024] [Accepted: 06/18/2024] [Indexed: 06/25/2024] Open
Abstract
Obstructive uropathy is defined as the structural or functional interruption of urinary outflow at any level in the urinary tract. It is regarded as one of the most prevalent causes of acute kidney injury (AKI), accounting for 5%-10% of cases. Acute severe obstruction of the urinary tract is a potentially threatening situation for the kidneys and therefore requires prompt identification and management to relieve obstruction. The aim of the present article is to review and synthesize available evidence on obstructive uropathy, providing a clinical guideline for clinicians. A literature review on obstructive uropathy in the context of AKI was performed, focusing on the least clarified aspects regarding diagnosis and management. Recent literature searching was conducted in English and top-level evidence articles including systematic reviews, metanalyses and large series were prioritized. Acute obstruction of the urinary tract is a diagnostic and therapeutical challenge that may lead to important clinical complications together with direct structural and hemodynamic damage to the kidney. Early recognition of the leading cause and its exact location is essential to ensure prompt urinary drainage together with the most suitable drainage technique selection. A multidisciplinary approach, including urologists, nephrologists, and other medical specialties, is best suited to correctly manage concomitant hemodynamic changes, fluid and electrolyte imbalances, and other related issues. Obstructive uropathy is one of the leading causes of AKI. Recognition of patients suitable for early diversion and feasibility or adequate selection of the indicated technique is sometimes challenging. A thorough understanding of the physiopathology behind the development of urinary obstruction is vital for correct diagnosis and management.
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Affiliation(s)
- Xabier Pérez-Aizpurua
- Department of Urology, Hospital Universitario Fundación Jiménez Díaz, Madrid 28015, Madrid, Spain
| | - Ramiro Cabello Benavente
- Department of Urology, Hospital Universitario Fundación Jiménez Díaz, Madrid 28015, Madrid, Spain
| | - Gonzalo Bueno Serrano
- Department of Urology, Hospital Universitario Fundación Jiménez Díaz, Madrid 28015, Madrid, Spain
| | - José María Alcázar Peral
- Department of Urology, Hospital Universitario Fundación Jiménez Díaz, Madrid 28015, Madrid, Spain
| | | | - Jaime Tufet i Jaumot
- Department of Urology, Hospital Universitario Fundación Jiménez Díaz, Madrid 28015, Madrid, Spain
| | | | - Felipe Osorio Ospina
- Department of Urology, Hospital Universitario Fundación Jiménez Díaz, Madrid 28015, Madrid, Spain
| | - Carmen Gonzalez-Enguita
- Department of Urology, Hospital Universitario Fundación Jiménez Díaz, Madrid 28015, Madrid, Spain
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Stevens K, Hultin H, Sundbom M. Hypovitaminosis D and hyperparathyroidism: a 5-year postoperative follow-up of 30,458 gastric bypass and sleeve gastrectomy patients. Surg Obes Relat Dis 2024:S1550-7289(24)00076-5. [PMID: 38614927 DOI: 10.1016/j.soard.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/13/2024] [Accepted: 02/10/2024] [Indexed: 04/15/2024]
Abstract
BACKGROUND Bariatric procedures are associated with nutrient deficiencies. Studies show an association between gastric bypass (Roux-en-Y gastric bypass [RYGB]) and hypovitaminosis D as well as hyperparathyroidism, yet few compare RYGB to sleeve gastrectomy (SG), and large long-term analyses are scarce. OBJECTIVE Evaluate trends of vitamin D and parathyroid hormone (PTH) levels in RYGB and SG. SETTING National quality register. METHOD The Scandinavian Obesity Surgery Registry records all bariatric surgeries in Sweden. Data from 2008 to 2021 on primary RYGB or SG with reported 25-hydroxy vitamin D (25-OH-D) and/or PTH levels were included. Individuals with an estimated glomerular filtration rate of <60 mL/min/1.73 m2 were excluded, leaving a study population of 25,385 RYGB and 5073 SG patients. RESULTS A decrease in 25-OH-D, mirrored by an increase in PTH, was observed after the first year for both procedures, but more pronounced in RYGB. At 5 years, 25-OH-D levels were still higher than at baseline. Regular supplementation resulted in better 25-OH-D and PTH levels. Linear regression found that procedure type (RYGB versus SG), 25-OH-D levels, and time since surgery were significant factors in predicting PTH levels. The risk of pathologic PTH levels (>7 pmol/L) at 2 and 5 years postoperatively was roughly three times higher in RYGB (odds ratios = 3.41 and 2.84, respectively). CONCLUSIONS Previous studies alongside these results suggest that RYGB, more so than SG, may cause hypovitaminosis D and thereby hyperparathyroidism, which could lead to osteopenia. The threshold for 25-OH-D should be >75 nmol/L, and despite higher levels, current vitamin D supplementation may not be sufficient. Follow-up should include screening for hyperparathyroidism and hypovitaminosis D.
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Affiliation(s)
- Katharina Stevens
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
| | - Hella Hultin
- Södersjukhuset Department of Surgery, Karolinska University, Stockholm Sweden
| | - Magnus Sundbom
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
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Ke G, Xie Z, Xiao J, Zhang Y, Hu Y, Li B, Jiang N, Chen X, Liu S, Shi W. Comparison of 6 equations for estimating glomerular filtration rate in a Chinese benign hypertensive nephrosclerosis population. Medicine (Baltimore) 2021; 100:e28318. [PMID: 34941129 PMCID: PMC8701793 DOI: 10.1097/md.0000000000028318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 11/24/2021] [Indexed: 01/05/2023] Open
Abstract
Equations to estimate glomerular filtration rate (eGFR) are useful for monitoring tje renal status of benign hypertensive nephrosclerosis (BHN). This study aimed to compare the applicability of 6 equations (Cockcroft-Gault [CG] adjusted for body surface area, original modification of diet in renal disease [MDRD], American abbreviated MDRD, Chinese modified MDRD, Chinese abbreviated MDRD, and Chronic Kidney Disease Epidemiology [CKD-EPI]) to estimate GFR in a Chinese BHN population. A total of 179 patients diagnosed with BHN were enrolled. The GFR estimated by each equation was compared to the reference GFR (rGFR) measured using the dual plasma sampling technetium-labeled diethylenetriaminepentaacetic acid method. The Chinese modified and Chinese abbreviated MDRD equations overestimated the rGFR, while the CG, CG adjusted for body surface area, original MDRD, American abbreviated MDRD, and CKD-EPI equations underestimated the rGFR. The difference in performance between estimated GFR (eGFR) based on the American abbreviated MDRD equation and the rGFR was not statistically significant (P = .191), while differences in the others were statistically significant (P < .05). Furthermore, the advantages in deviation, absolute deviation, deviation degree, precision, and accuracy were also significantly different from those of the other equations. Our findings suggest that eGFR based on the American abbreviated MDRD equation is suitable for the Chinese BHN population.
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Affiliation(s)
- Guibao Ke
- Department of Nephrology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, Guangdong, China
- Department of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
- Department of Nephrology, Affiliated Hospital/Clinical Medical College of Chengdu University, Chengdu, Sichuan, China
| | - Zhibin Xie
- Department of Nephrology, Zhongshan City People's Hospital, Zhongshan, Guangdong, China
| | - Jie Xiao
- Department of Nephrology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yamei Zhang
- Department of Nephrology, Affiliated Hospital/Clinical Medical College of Chengdu University, Chengdu, Sichuan, China
| | - Yao Hu
- Department of Nephrology, Affiliated Hospital/Clinical Medical College of Chengdu University, Chengdu, Sichuan, China
| | - Bohou Li
- Department of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Nan Jiang
- Department of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Xueqin Chen
- Department of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Shuangxin Liu
- Department of Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Wei Shi
- Department of Nephrology, Gaozhou City People's Hospital, Gaozhou, Guangdong, China
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Busse D, Borghardt JM, Petroff D, Pevzner A, Dorn C, El-Najjar N, Huisinga W, Wrigge H, Simon P, Kloft C. Evaluating prediction methods for glomerular filtration to optimise drug doses in obese and nonobese patients. Br J Clin Pharmacol 2021; 88:2973-2981. [PMID: 34688225 DOI: 10.1111/bcp.15115] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 08/19/2021] [Accepted: 10/03/2021] [Indexed: 01/02/2023] Open
Abstract
AIMS The most suitable method for predicting the glomerular filtration rate (GFR) in obesity is currently debated. Therefore, multiple GFR/creatinine clearance prediction methods were applied to (morbidly) obese and nonobese patients ranging from moderate renal impairment to glomerular hyperfiltration and their predictions were rated based on observed fosfomycin pharmacokinetics, as this model drug is exclusively eliminated via glomerular filtration. METHODS The GFR/creatinine clearance predictions via the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Modification of Diet in Renal Disease (MDRD; indexed and de-indexed by body surface area) and creatinine clearance via the Cockcroft-Gault formula (CLCRCG ) using different body size descriptors were compared to the fosfomycin clearance (CLFOF ) from 30 surgical patients (body mass index = 20.1-52.0 kg m-2 ), receiving 8000 mg as intravenous infusion. RESULTS The concordance between CLFOF and creatinine clearance predictions was highest for CLCRCG employing either ideal body weight or adjusted body weight (if body mass >1.3 ideal body weight; CLCRCG_ABW-Schwartz , concordance-correlation coefficient [95% confidence interval] = 0.474 [0.156; 0.703], CCC) and GFR predictions via the de-indexed MDRD equation (concordance-correlation coefficient = 0.452 [0.137; 0.685]). The proportion of predicted GFR values within ±30% of the observed CLFOF (P30 = 72.3-76.7%) was only marginally lower than the reported P30 in the original CKD-EPI and MDRD publications (P30 = 84.1-90.0%). CONCLUSION This analysis represents a successful proof-of-concept for evaluating GFR/creatinine clearance prediction methods: Across all body mass index classes CLCRCG_ABW-Schwartz or the de-indexed MDRD were most suitable for predicting creatinine clearance/GFR also in (morbidly) obese, CKD stage <3B individuals in therapeutic use. Their application is proposed in optimising doses for vital therapies in obese patients requiring monitoring of renal function (e.g. methotrexate dosing).
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Affiliation(s)
- David Busse
- Institute of Pharmacy, Department of Clinical Pharmacy and Biochemistry, Freie Universitaet Berlin, Berlin, Germany.,Graduate Research Training program PharMetrX, Berlin/Potsdam, Germany
| | - Jens Markus Borghardt
- Drug Discovery Sciences, Research DMPK, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - David Petroff
- Integrated Research and Treatment Center (IFB) Adiposity Diseases, University of Leipzig, Leipzig, Germany.,Clinical Trial Centre Leipzig, University of Leipzig, Leipzig, Germany
| | - Alice Pevzner
- Institute of Pharmacy, Department of Clinical Pharmacy and Biochemistry, Freie Universitaet Berlin, Berlin, Germany
| | - Christoph Dorn
- University of Regensburg, Institute of Pharmacy, Regensburg, Germany
| | - Nahed El-Najjar
- Institute of Clinical Microbiology and Hygiene, Faculty of Medicine, University Hospital Regensburg, Regensburg, Germany
| | - Wilhelm Huisinga
- University of Potsdam, Institute of Mathematics, Potsdam, Germany
| | - Hermann Wrigge
- Clinical Trial Centre Leipzig, University of Leipzig, Leipzig, Germany.,Department of Anesthesiology, Intensive Care and Emergency Medicine, Pain Therapy, Bergmannstrost Hospital Halle, Halle, Germany
| | - Philipp Simon
- Integrated Research and Treatment Center (IFB) Adiposity Diseases, University of Leipzig, Leipzig, Germany.,Department of Anaesthesiology and Intensive Care Medicine, University of Leipzig, Leipzig, Germany
| | - Charlotte Kloft
- Institute of Pharmacy, Department of Clinical Pharmacy and Biochemistry, Freie Universitaet Berlin, Berlin, Germany
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Li J, Xu X, Luo J, Chen W, Yang M, Wang L, Zhu N, Yuan W, Gu L. Choosing an appropriate glomerular filtration rate estimating equation: role of body mass index. BMC Nephrol 2021; 22:197. [PMID: 34034674 PMCID: PMC8145837 DOI: 10.1186/s12882-021-02395-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 05/04/2021] [Indexed: 11/10/2022] Open
Abstract
Background We aimed to investigate the accuracy of different equations in evaluating estimated glomerular filtration rate (eGFR) in a Chinese population with different BMI levels. Methods A total of 837 Chinese patients were enrolled, and the eGFRs were calculated by three Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations, three full-age spectrum (FAS) equations and two Modification of Diet in Renal Disease (MDRD) equations. Results of measured GFR (mGFR) by the 99Tcm-diathylenetriamine pentaacetic acid (99Tcm-DTPA) renal dynamic imaging method were the reference standards. According to BMI distribution, the patients were divided into three intervals: below 25th(BMIP25), 25th to 75th(BMIP25–75) and over 75th percentiles (BMIP75). Results The medium BMI of the three BMI intervals were 20.9, 24.8 and 28.9 kg/m2, respectively. All deviations from mGFR (eGFR) were correlated with BMI (p < 0.05). The percentage of cases in which eGFR was within mGFR ±30% (P30) was used to represent the accuracy of each equation. Overall, eGFRFAS_Cr_CysC and eGFREPI_Cr_2009 performed similarly, showing the best agreement with mGFR among the eight equations in Bland-Altman analysis (biases: 4.1 and − 4.2 mL/min/1.73m2, respectively). In BMIP25 interval, eGFRFAS_Cr got − 0.7 of the biases with 74.2% of P30, the kappa value was 0.422 in classification of CKD stages and the AUC60 was 0.928 in predicting renal insufficiency, and eGFREPI_Cr_2009 got 2.3 of the biases with 71.8% of P30, the kappa value was 0.418 in classification of CKD stages and the AUC60 was 0.920 in predicting renal insufficiency. In BMIP25–75 interval, the bias of eGFRFAS_Cr_CysC was 4.0 with 85.0% of P30, the kappa value was 0.501 and the AUC60 was 0.941, and eGFRFAS_Cr_CysC showed balanced recognition ability of each stage of CKD (62.3, 63.7, 68.0, 71.4 and 83.3% respectively). In BMIP75 interval, the bias of eGFREPI_Cr_CysC_2012 was 3.8 with 78.9% of P30, the kappa value was 0.484 the AUC60 was 0.919, and eGFREPI_Cr_CysC_2012 equation showed balanced and accurate recognition ability of each stage (60.5, 60.0, 71.4, 57.1 and 100% respectively). In BMIP75 interval, the bias of eGFRFAS_Cr_CysC was − 1.8 with 78.5% of P30, the kappa value was 0.485, the AUC60 was 0.922. However, the recognition ability of each stage of eGFRFAS_Cr_CysC eq. (71.1, 61.2, 70.0, 42.9 and 50.0% respectively) was not as good as GFREPI_Cr_CysC_2012 equation. Conclusion For a Chinese population, we tend to recommend choosing eGFRFAS_Cr and eGFREPI_Cr_2009 when BMI was around 20.9, eGFRFAS_Cr_CysC when BMI was near 24.8, and eGFREPI_Cr_CysC_2012 when BMI was about 28.9. Supplementary Information The online version contains supplementary material available at 10.1186/s12882-021-02395-x.
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Affiliation(s)
- Jiayong Li
- Clinical Laboratory Medicine Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Xiang Xu
- Clinical Laboratory Medicine Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Jialing Luo
- Clinical Laboratory Medicine Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Wenjing Chen
- Clinical Laboratory Medicine Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Man Yang
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Ling Wang
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Nan Zhu
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Weijie Yuan
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Lijie Gu
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China.
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The failure of glomerular filtration rate estimating equations among obese population. PLoS One 2020; 15:e0242447. [PMID: 33206712 PMCID: PMC7673537 DOI: 10.1371/journal.pone.0242447] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 11/03/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Obesity is a major public health with increasing numbers of obese individuals are at risk for kidney disease. However, the validity of serum creatinine-based glomerular filtration rate (GFR) estimating equations in obese population is yet to be determined. METHODS We evaluated the performance of the reexpressed Modification of Diet in Renal Disease (MDRD), reexpressed MDRD with Thai racial factor, Thai estimated GFR (eGFR) as well as Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations among obese patients, defined as body mass index (BMI) ≥25 kg/m2 with the reference measured GFR (mGFR) determined by 99mTc-diethylene triamine penta-acetic acid (99mTc-DTPA) plasma clearance method. Serum creatinine levels were measured using standardized enzymatic method simultaneously with GFR measurement. The statistical methods in assessing agreement for continuous data including total deviation index (TDI), concordance correlation coefficient (CCC), and coverage probability (CP) for each estimating equation were compared with the reference mGFR. Accuracy within 10% representing the percentage of estimations falling within the range of ±10% of mGFR values for all equations were also tested. RESULTS A total of 240 Thai obese patients were finally recruited with mean BMI of 31.5 ± 5.8 kg/m2. In the total population, all eGFR equations underestimated the reference mGFR. The average TDI values were 55% indicating that 90% of the estimates falling within the range of -55 to +55% of the reference mGFR. The CP values averaged 0.23 and CCC scores ranged from 0.75 to 0.81, reflecting the low to moderate levels of agreement between each eGFR equation and the reference mGFR. The proportions of patients achieving accuracy 10% ranged from 23% for the reexpressed MDRD equation to 33% for the Thai eGFR formula. Among participants with BMI more than 35 kg/m2 (n = 48), the mean error of all equations was extremely wide and significantly higher for all equations compared with the lower BMI category. Also, the strength of agreement evaluated by TDI, CCC, and CP were low in the subset of patients with BMI ≥35 kg/m2. CONCLUSION Estimating equations generally underestimated the reference mGFR in subjects with obesity. The overall performance of GFR estimating equations demonstrated poor concordance with the reference mGFR among individuals with high BMI levels. In certain clinical settings such as decision for dialysis initiation, the direct measurements of GFR are required to establish real renal function among obese population.
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Chang AR, George J, Levey AS, Coresh J, Grams ME, Inker LA. Performance of Glomerular Filtration Rate Estimating Equations Before and After Bariatric Surgery. Kidney Med 2020; 2:699-706.e1. [PMID: 33319195 PMCID: PMC7729215 DOI: 10.1016/j.xkme.2020.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Rationale & Objective Evaluation of glomerular filtration rate (GFR) is challenging in adults undergoing bariatric surgery because creatinine and cystatin C levels are influenced by changes in muscle and fat mass. Additionally, indexing of GFR by body surface area (BSA) may by affected by decreases in BSA. Study Design Prospective observational study. Setting & Participants 27 adults with body mass index (BMI) ≥ 35 kg/m2 who underwent measurement of GFR before and after bariatric surgery. Outcomes Indexed and nonindexed GFRs measured (mGFRs) using plasma iohexol clearance, indexed and nonindexed estimated GFR (eGFR) based on levels of creatinine, cystatin C, or both from Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. Analytic Approach Bias and percent of estimates within 20% and 30% of mGFR (P20 and P30) for estimating equations were examined. Results Mean presurgery BMI was 49.5 (SD, 9.4) kg/m2, BSA was 2.42 (SD, 0.27) m2, nonindexed mGFR was 117.3 (SD, 34.1) mL/min, and indexed mGFR was 84.1 (SD, 22.0) mL/min/1.73 m2. After 6 months, mean BMI changed by –13.8 (95% CI, −15.9 to −11.8) kg/m2, BSA by −0.30 (95% CI, −0.33 to −0.27) m2, and nonindexed mGFR by −9.2 (95% CI, −17.2 to −1.1) mL/min, while indexed mGFR was unchanged at 5.1 (95% CI, −0.1 to 10.4) mL/min/1.73 m2. Nonindexed eGFRcr was unbiased (median bias, 5.0 [95% CI, −4.3 to 11.6] mL/min) before surgery, but overestimated mGFR (8.8 [95% CI, 1.8 to 16.9] mL/min) after surgery. Nonindexed eGFRcys underestimated mGFR before (median bias, −12.1 [95% CI, −21.4 to −1.2] mL/min) and after surgery (−11.2 [95% CI, −21.8 to −7.3] mL/min). Nonindexed eGFRcr-cys was unbiased before (median bias, −6.0 [95% CI, −11.0 to 1.0] mL/min) and after surgery (−2.0 [95% CI, −8.8 to 4.9] mL/min). Findings were similar for indexed eGFR compared with indexed mGFR. Limitations Small, mostly white sample. Conclusions Changes in indexed and nonindexed GFRs may be discordant after bariatric surgery in adults because of decreases in BSA. Indexed and nonindexed eGFRcr-cys may be less biased than indexed or nonindexed eGFRcr or eGFRcys because of opposite biases in estimating mGFR.
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Affiliation(s)
- Alex R. Chang
- Kidney Health Research Institute, Geisinger, Danville, PA
- Department of Population Health Sciences, Geisinger, Danville, PA
- Address for Correspondence: Alex R. Chang, MD, MS, 100 N Academy Ave, Danville, PA 17822.
| | - Jason George
- Department of Population Health Sciences, Geisinger, Danville, PA
| | | | - Josef Coresh
- Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins University, Baltimore, MD
- Divison of Nephrology, Johns Hopkins University, Baltimore, MD
| | - Morgan E. Grams
- Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins University, Baltimore, MD
- Divison of Nephrology, Johns Hopkins University, Baltimore, MD
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Assessment of Kidney Function in Patients With Extreme Obesity: A Narrative Review. Ann Pharmacother 2020; 55:80-88. [DOI: 10.1177/1060028020935580] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Objectives: To discuss the evidence and caveats associated with estimated and measured creatinine clearance (eClCr and mClCr) and glomerular filtration rate (eGFR and mGFR) assessments of kidney function in patients with more extreme forms of obesity. Data Sources: PubMed (1976 to mid-May 2020) was used, with bibliographies of retrieved articles searched for additional articles. Study Selection and Data Extraction: Articles using gold standard mGFR to evaluate eClCr, mClCr, and eGFR assessments of kidney function in patients with more extreme forms of obesity were included. Data Synthesis: The overestimation of GFR by mClCr is well established, but mClCr is an alternative to mGFR assessments for determining medication dosing in patients with extremes of body size or muscle mass, or in patients receiving narrow therapeutic index medications when eGFR is likely to be inaccurate. The vast majority of studies comparing eGFR assessments with gold standard indicators of kidney function were attempts to validate eGFR equations for diagnosing and staging chronic kidney disease (CKD). Relevance to Patient Care and Clinical Practice: For dosing medications in patients with stable kidney function and extreme obesity, a deindexed 4-variable Modification of Diet in Renal Disease or CKD Epidemiology Collaboration equation is an alternative to Cockcroft-Gault. Consistent use of the same equation by provider and between providers within any given setting is of paramount importance. Conclusions: In patients with extreme obesity and stable kidney function, eClCr or eGFR using deindexed values provides estimates of function for dosing adjustments of medications with elimination by the kidneys, but more research is needed with respect to the best size descriptor to use with estimating equations.
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Guebre-Egziabher F, Brunelle C, Thomas J, Pelletier CC, Normand G, Juillard L, Dubourg L, Lemoine S. Estimated Glomerular Filtration Rate Bias in Participants with Severe Obesity Regardless of Deindexation. Obesity (Silver Spring) 2019; 27:2011-2017. [PMID: 31579999 DOI: 10.1002/oby.22574] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 05/23/2019] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Morbid obesity is associated with a higher independent risk of chronic kidney disease (CKD). Estimated glomerular filtration rate (eGFR) has been evaluated in a limited number of study participants with severe obesity. METHODS A total of 706 measured GFR (mGFR) results from 598 participants with obesity (BMI ≥ 35 kg/m2 ) were retrospectively collected. The performance of the Modification of Diet in Renal Disease (MDRD) equation, Chronic Kidney Disease-Epidemiology (CKD-EPI) equation, and deindexed eGFR were compared with mGFR from the gold standard technique (inuline or iohexol), adjusted (mGFRr) or nonadjusted (mGFR) to body surface area. Absolute bias, precision, and accuracy were calculated. RESULTS Mean mGFRr (58 ± 31 mL/min/1.73 m2 ) was significantly different from CKD-EPI and MDRD (P < 0.001). Mean mGFR (nonindexed) (70 ± 40 mL/min) was significantly higher than mGFRr (P < 0.001). eGFR showed important biases and low accuracies for CKD-EPI and MDRD (10.7 ± 10.7 and 12.2 ± 13.7 mL/min/1.73 m2 ; 78% vs. 75% respectively). Deindexation worsened bias and accuracy 30% (percentage of GFR estimates within 30% of mGFRr or mGFR) between eGFR and mGFR. CONCLUSIONS eGFR overestimates mGFR and is associated with important biases and inaccuracies in patients with severe obesity, and deindexing eGFR worsens the overestimation. These findings may have important implications in examining kidney function in patients with obesity.
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Affiliation(s)
- Fitsum Guebre-Egziabher
- Nephrology and Renal Function Unit, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France
- Faculté de Médecine Lyon Est, Université Lyon-1 Claude Bernard, Lyon, France
- INSERM U1060, CarMeN Laboratory, Lyon, France
- Federation Hospitalo-Universitaire FHU-DO-IT, Lyon, France
| | - Charlotte Brunelle
- Nephrology and Renal Function Unit, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France
- INSERM U1060, CarMeN Laboratory, Lyon, France
| | - Jouve Thomas
- Nephrology Unit, Centre Hospitalo Universitaire Grenoble Alpes, La Tronche, France
| | - Caroline C Pelletier
- Nephrology and Renal Function Unit, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France
- INSERM U1060, CarMeN Laboratory, Lyon, France
| | - Gabrielle Normand
- Nephrology and Renal Function Unit, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France
- Faculté de Médecine Lyon Est, Université Lyon-1 Claude Bernard, Lyon, France
- INSERM U1060, CarMeN Laboratory, Lyon, France
| | - Laurent Juillard
- Nephrology and Renal Function Unit, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France
- Faculté de Médecine Lyon Est, Université Lyon-1 Claude Bernard, Lyon, France
- INSERM U1060, CarMeN Laboratory, Lyon, France
- Federation Hospitalo-Universitaire FHU-DO-IT, Lyon, France
| | - Laurence Dubourg
- Nephrology and Renal Function Unit, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France
- Faculté de Médecine Lyon Est, Université Lyon-1 Claude Bernard, Lyon, France
- UMR 5305 CNRS, Université Lyon 1, Université de Lyon, Biologie tissulaire et ingénierie thérapeutique, Lyon, France
| | - Sandrine Lemoine
- Nephrology and Renal Function Unit, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France
- Faculté de Médecine Lyon Est, Université Lyon-1 Claude Bernard, Lyon, France
- INSERM U1060, CarMeN Laboratory, Lyon, France
- Federation Hospitalo-Universitaire FHU-DO-IT, Lyon, France
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10
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Vlasschaert C, Thibodeau S, Parmar MS. De-indexed estimated glomerular filtration rates: A simple step towards improving accuracy of drug dosing of renally excreted medications in moderate to severe obesity. Nephrology (Carlton) 2019; 25:29-31. [PMID: 31148303 DOI: 10.1111/nep.13621] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2019] [Indexed: 10/26/2022]
Abstract
Kidney function is underestimated in obese individuals when standard equations are applied. Laboratory-reported estimated glomerular filtration rates (eGFR) report glomerular filtration rates corrected for body surface area in mL/min per 1.73 m2 using modification of diet in renal disease or the chronic kidney disease-Epidemiology Collaboration equations. This may result in premature discontinuation or reduction in dosage of renally excreted medications. Currently, there are no clinical guidelines defining thresholds beyond which physicians should consider de-indexing patient eGFR values. We compared standard and de-indexed eGFR values for 281 consecutive patients seen in our chronic kidney disease clinic. In our study, half of the patients with a body mass index above 35 had clinically significant changes in their eGFR, with an improvement in chronic kidney disease stage, when eGFR was de-indexed. We propose that eGFR de-indexing should be considered in patients with moderate to severe obesity when calculating the dose, especially for medications that are excreted by the kidneys.
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Affiliation(s)
- Caitlyn Vlasschaert
- Department of Medicine, Clinical Sciences, Northern Ontario School of Medicine, Ontario, Canada
| | - Stephane Thibodeau
- Department of Medicine, Clinical Sciences, Northern Ontario School of Medicine, Ontario, Canada
| | - Malvinder S Parmar
- Department of Medicine, Clinical Sciences, Northern Ontario School of Medicine, Ontario, Canada
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11
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Higdon EA, Kimmons LA, Duhart BT, Hudson JQ. Disagreement in Estimates of Kidney Function for Drug Dosing in Obese Inpatients. J Pharm Pract 2017; 32:41-47. [PMID: 29105574 DOI: 10.1177/0897190017737895] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND: The Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations are used to estimate kidney function. However, utility has been questioned in the obese population. OBJECTIVE: To evaluate differences in estimates of kidney function in obese patients and implications for drug dosing. METHODS: This was a retrospective study of adult inpatients with a body mass index ≥30 kg/m2 and stable kidney function. Patients were categorized based on creatinine clearance (CrCl): group 1-CrCl ≥ 60 mL/min and group 2-CrCl 15 to 59 mL/min. Mean estimates of kidney function and recommended doses of 8 renally eliminated medications were compared. RESULTS: For the 166 patients included, mean estimates using CG, MDRD, and CKD-EPI for group 1 were 87 (23) mL/min, 91 (21) mL/min, and 96 (23) mL/min, respectively. Group 2 estimates were 42 (13) mL/min, 51 (15) mL/min, and 51 (16) mL/min, respectively. MDRD and CKD-EPI estimates were significantly higher than CG in 125 (75%) and 140 (84%) patients, respectively. Dose discrepancies were most often due to higher dose recommendations using MDRD or CKD-EPI compared to CG. CONCLUSION: Careful consideration of the method used to estimate kidney function, the method used for developing dosing recommendations, and the risk-benefit profile is warranted when designing drug regimens in obese individuals.
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Affiliation(s)
- Emily A Higdon
- 1 Department of Pharmacy, University of Kentucky HealthCare, Lexington, KY, USA
| | - Lauren A Kimmons
- 2 Department of Pharmacy, Methodist University Hospital, Memphis, TN, USA
| | - Benjamin T Duhart
- 3 Department of Clinical Pharmacy, The University of Tennessee, Memphis, TN, USA
| | - Joanna Q Hudson
- 3 Department of Clinical Pharmacy, The University of Tennessee, Memphis, TN, USA.,4 Department of Medicine (Nephrology), The University of Tennessee, Memphis, TN, USA
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12
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Donadio C, Moriconi D, Berta R, Anselmino M. Estimation of Urinary Creatinine Excretion and Prediction of Renal Function in Morbidly Obese Patients: New Tools from Body Composition Analysis. Kidney Blood Press Res 2017; 42:629-640. [DOI: 10.1159/000481630] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/06/2017] [Indexed: 11/19/2022] Open
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13
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Abstract
PURPOSE OF REVIEW Several interrelated mechanisms promote the development of hypertension in obesity, often contributing to end organ damage including cardiovascular disease and chronic kidney disease. RECENT FINDINGS The treatment of hypertension in obesity is complicated by a high prevalence of resistant hypertension, as well as unpredictable hemodynamic effects of many medications. Weight loss stabilizes neurohormonal activity and causes clinically significant reductions in blood pressure. While lifestyle interventions can improve blood pressure, they fail to consistently yield sustained weight loss and have not demonstrated long-term benefits. Bariatric surgery provides more permanent weight reduction, corresponding with dramatic declines in blood pressure and attenuation of long-term cardiovascular risk. Hypertension is closely linked to the prevalence, pathophysiology, and morbidity of obesity. There are multiple barriers to managing hypertension in obesity. Surgical weight loss offers the most promise in reducing blood pressure and decreasing end organ damage in this patient population.
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Smirnov AV, Kayukov IG, Rumyantsev AS. PROBLEM OF THE ASSESMENT OF GLOMERULAR FILTRATION RATE IN OBESITY. ACTA ACUST UNITED AC 2017. [DOI: 10.24884/1561-6274-2017-21-2-20-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The article discusses the problem of choosing an adequate method of assessing glomerular filtration rate in overweight and obesity.
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Affiliation(s)
- A. V. Smirnov
- First Pavlov Saint Petersburg State Medical University
| | - I. G. Kayukov
- First Pavlov Saint Petersburg State Medical University
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15
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Abstract
Chronic kidney disease (CKD) is currently defined by abnormalities of kidney structure or function assessed using a matrix of variables - including glomerular filtration rate (GFR), thresholds of albuminuria and duration of injury - and is considered by many to be a common disorder globally. However, estimates of CKD prevalence vary widely, both within and between countries. The reasons for these variations are manifold, and include true regional differences in CKD prevalence, vagaries of using estimated GFR (eGFR) for identifying CKD, issues relating to the use of set GFR thresholds to define CKD in elderly populations, and concerns regarding the use of one-off testing for assessment of eGFR or albuminuria to define the prevalence of CKD in large-scale epidemiological studies. Although CKD is common, the suggestion that its prevalence is increasing in many countries might not be correct. Here, we discuss the possible origins of differences in estimates of CKD prevalence, and present possible solutions for tackling the factors responsible for the reported variations in GFR measurements. The strategies we discuss include approaches to improve testing methodologies for more accurate assessment of GFR, to improve awareness of factors that can alter GFR readouts, and to more accurately stage CKD in certain populations, including the elderly.
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16
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A Population Pharmacokinetic Model for 51Cr EDTA to Estimate Renal Function. Clin Pharmacokinet 2016; 56:671-678. [DOI: 10.1007/s40262-016-0489-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Vitolo E, Santini E, Salvati A, Volterrani D, Duce V, Bruno RM, Solini A. Metabolic and Hormonal Determinants of Glomerular Filtration Rate and Renal Hemodynamics in Severely Obese Individuals. Obes Facts 2016; 9:310-320. [PMID: 27701167 PMCID: PMC5644791 DOI: 10.1159/000446965] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 05/16/2016] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE Renal function is often compromised in severe obesity. A true measurement of glomerular filtration rate (GFR) is unusual, and how estimation formulae (EstForm) perform in such individuals is unclear. We characterized renal function and hemodynamics in severely obese individuals, assessing the reliability of EstForm. METHODS We measured GFR (mGFR) by iohexol plasma clearance, renal plasma flow (RPF) by 123I-ortho-iodo-hippurate, basal and stimulated vascular renal indices, endothelium-dependent and -independent vasodilation using flow-mediated dilation (FMD) as well as metabolic and hormonal profile in morbid, otherwise healthy, obese subjects. RESULTS Compared with mGFR, the better performing EstForm was CKD-EPI (5.3 ml/min/1.73 m2 bias by Bland-Altman analysis). mGFR was directly related with RPF, total and incremental glucose AUC, and inversely with PTH and h8 cortisol. Patients with mGFR below the median shown significantly higher PTH and lower vitamin D3. Basal or dynamic renal resistive index, FMD, pulse wave velocity were not related with mGFR. In an adjusted regression model, renal diameter and plasma flow remained related with mGFR (R2 = 0.67), accounting for 15% and 21% of mGFR variance, respectively. CONCLUSIONS CKD-EPI formula should be preferred in morbid obesity; glucose increments during oral glucose tolerance test correlate with hyperfiltration; RPF and diameter are independent determinants of mGFR; slightly high PTH values, frequent in obesity, might influence mGFR.
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Affiliation(s)
- Edoardo Vitolo
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Eleonora Santini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Antonio Salvati
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Duccio Volterrani
- Department of Translational Research and Novel Technologies, University of Pisa, Pisa, Italy
| | - Valerio Duce
- Department of Translational Research and Novel Technologies, University of Pisa, Pisa, Italy
| | - Rosa Maria Bruno
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Anna Solini
- Department of Translational Research and Novel Technologies, University of Pisa, Pisa, Italy
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18
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Delanaye P, Melsom T, Ebert N, Bäck SE, Mariat C, Cavalier E, Björk J, Christensson A, Nyman U, Porrini E, Remuzzi G, Ruggenenti P, Schaeffner E, Soveri I, Sterner G, Eriksen BO, Gaspari F. Iohexol plasma clearance for measuring glomerular filtration rate in clinical practice and research: a review. Part 2: Why to measure glomerular filtration rate with iohexol? Clin Kidney J 2016; 9:700-4. [PMID: 27679716 PMCID: PMC5036903 DOI: 10.1093/ckj/sfw071] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 07/11/2016] [Indexed: 12/11/2022] Open
Abstract
A reliable assessment of glomerular filtration rate (GFR) is of paramount importance in clinical practice as well as epidemiological and clinical research settings. It is recommended by Kidney Disease: Improving Global Outcomes guidelines in specific populations (anorectic, cirrhotic, obese, renal and non-renal transplant patients) where estimation equations are unreliable. Measured GFR is the only valuable test to confirm or confute the status of chronic kidney disease (CKD), to evaluate the slope of renal function decay over time, to assess the suitability of living kidney donors and for dosing of potentially toxic medication with a narrow therapeutic index. Abnormally elevated GFR or hyperfiltration in patients with diabetes or obesity can be correctly diagnosed only by measuring GFR. GFR measurement contributes to assessing the true CKD prevalence rate, avoiding discrepancies due to GFR estimation with different equations. Using measured GFR, successfully accomplished in large epidemiological studies, is the only way to study the potential link between decreased renal function and cardiovascular or total mortality, being sure that this association is not due to confounders, i.e. non-GFR determinants of biomarkers. In clinical research, it has been shown that measured GFR (or measured GFR slope) as a secondary endpoint as compared with estimated GFR detected subtle treatment effects and obtained these results with a comparatively smaller sample size than trials choosing estimated GFR. Measuring GFR by iohexol has several advantages: simplicity, low cost, stability and low interlaboratory variation. Iohexol plasma clearance represents the best chance for implementing a standardized GFR measurement protocol applicable worldwide both in clinical practice and in research.
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Affiliation(s)
- Pierre Delanaye
- Department of Nephrology, Dialysis and Transplantation, University of Liège Hospital (ULg CHU), 4000 Liège, Belgium
| | - Toralf Melsom
- Metabolic and Renal Research Group, UiT The Arctic University of Norway and Section of Nephrology, University Hospital of North Norway, Tromsø, Norway
| | - Natalie Ebert
- Charité University Medicine, Institute of Public Health, Berlin, Germany
| | - Sten-Erik Bäck
- Department of Clinical Chemistry, Skåne University Hospital, Lund, Sweden
| | - Christophe Mariat
- Department of Nephrology, Dialysis, Transplantation and Hypertension, CHU Hôpital Nord, University Jean Monnet, PRES Université de LYON, Saint-Etienne, France
| | - Etienne Cavalier
- Department of Clinical Chemistry, University of Liège Hospital (ULg CHU), Liège, Belgium
| | - Jonas Björk
- Department of Occupational and Environmental Medicine, Lund University, Lund, Sweden
| | | | - Ulf Nyman
- Department of Translational Medicine, Division of Medical Radiology, Skåne University Hospital, Malmö, Sweden
| | - Esteban Porrini
- University of La Laguna, CIBICAN-ITB, Faculty of Medicine, Hospital Universtario de Canarias, Tenerife, Spain
| | - Giuseppe Remuzzi
- Centro di Ricerche Cliniche per le Malattie Rare ‘Aldo e Cele Daccò’, Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
- Unit of Nephrology, Azienda Socio Sanitaria Territoriale (ASST) Ospedale Papa Giovanni XXIII, Bergamo, Italy
| | - Piero Ruggenenti
- Centro di Ricerche Cliniche per le Malattie Rare ‘Aldo e Cele Daccò’, Istituto di Ricerche Farmacologiche Mario Negri, Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy
- Unit of Nephrology, Azienda Socio Sanitaria Territoriale (ASST) Ospedale Papa Giovanni XXIII, Bergamo, Italy
| | - Elke Schaeffner
- Charité University Medicine, Institute of Public Health, Berlin, Germany
| | - Inga Soveri
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Gunnar Sterner
- Department of Nephrology, Skåne University Hospital, Malmö, Sweden
| | - Bjørn Odvar Eriksen
- Metabolic and Renal Research Group, UiT The Arctic University of Norway and Section of Nephrology, University Hospital of North Norway, Tromsø, Norway
| | - Flavio Gaspari
- IRCCS - Istituto di Ricerche Farmacologiche ‘Mario Negri', Centro di Ricerche Cliniche per le Malattie Rare ‘Aldo e Cele Daccò', Ranica, Bergamo, Italy
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19
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Cohen JB, Stephens-Shields AJ, Denburg MR, Anderson AH, Townsend RR, Reese PP. Obesity, Renin-Angiotensin System Blockade and Risk of Adverse Renal Outcomes: A Population-Based Cohort Study. Am J Nephrol 2016; 43:431-40. [PMID: 27228992 DOI: 10.1159/000446862] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 05/06/2016] [Indexed: 01/09/2023]
Abstract
BACKGROUND Obesity substantially increases the risk of the development of chronic kidney disease. Adipose tissue expresses all of the components of the renin-angiotensin system (RAS), contributing to the high prevalence of hypertension in obese patients and driving renal hyperfiltration and subsequent glomerular injury. METHODS We performed a retrospective cohort study using a United Kingdom primary care database, evaluating the effect of time-updated exposure to RAS blockade versus all other antihypertensive medications in obese, hypertensive, non-diabetic patients. We used Cox proportional hazards modeling with and without marginal structural modeling to assess the hazards of developing a primary outcome of 50% reduction in estimated glomerular filtration rate (eGFR) (across 2 consecutive values), end stage renal disease or death. RESULTS A total of 219,701 patients met inclusion criteria, with a median 7.2 years of follow-up. Median baseline eGFR was 72.6 ml/min/1.73 m2. Compared to other antihypertensive medications, patients treated with RAS blockade had a modestly elevated hazard of adverse renal outcomes using traditional Cox regression (hazard ratio (HR) 1.04, 95% CI 1.01-1.07) and no significantly increased hazard by marginal structural modeling (HR 1.02, 95% CI 0.97-1.08). Patients treated with RAS blockade had a significantly reduced hazard of incident diabetes, but no significant difference in mortality. CONCLUSION This study, conducted in a large real-world cohort, provides evidence that RAS blockade may not provide benefit with regard to longitudinal renal outcomes in obese, hypertensive patients. Further research is needed to elucidate the hemodynamic and renoprotective role of antihypertensive medications in obese patients.
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Affiliation(s)
- Jordana B Cohen
- Renal, Electrolyte and Hypertension Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pa., USA
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20
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Bouquegneau A, Vidal-Petiot E, Moranne O, Mariat C, Boffa JJ, Vrtovsnik F, Scheen AJ, Krzesinski JM, Flamant M, Delanaye P. Creatinine-based equations for the adjustment of drug dosage in an obese population. Br J Clin Pharmacol 2016; 81:349-61. [PMID: 26531818 DOI: 10.1111/bcp.12817] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 10/21/2015] [Accepted: 10/24/2015] [Indexed: 12/30/2022] Open
Abstract
AIM For drug dosing adaptation, the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines recommend using estimated glomerular filtration rate (eGFR) by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, after 'de-indexation' by body surface area (BSA). In pharmacology, the Cockcroft-Gault (CG) equation is still recommended to adapt drug dosage. In the context of obesity, adjusted ideal body weight (AIBW) is sometimes preferred to actual body weight (ABW) for the CG equation. The aim of the present study was to compare the performance of the different GFR-estimating equations, non-indexed or de-indexed by BSA for the purpose of drug-dosage adaptation in obese patients. METHODS We analysed data from patients with a body mass index (BMI) higher than 30 kg m(-2) who underwent a GFR measurement. eGFR was calculated using the CKD-EPI and Modification of Diet in Renal Disease (MDRD) equations, de-indexed by BSA, and the CG equation, using either ABW, AIBW or lean body weight (LBW) for the weight variable and compared with measured GFR, expressed in ml min(-1). RESULTS In our population of obese patients, use of the AIBW instead of the ABW in the CG equation, markedly improved the overall accuracy of this equation [57% for CGABW and 79% for CGAIBW (P < 0.05)]. For high BMI (over 40 kg m(-2)), the accuracy of the CG equations is no different when using LBW than when using AIBW. The MDRD and CKD-EPI equations de-indexed by the BSA also performed well, with an overall higher accuracy for the MDRD de-indexed equation [(80% and 76%, respectively (P < 0.05)]. CONCLUSIONS The de-indexed MDRD equation appeared to be the most suitable for estimating the non-indexed GFR for the purpose of drug dosage adaptation in obese patients.
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Affiliation(s)
- Antoine Bouquegneau
- Department of Nephrology-Dialysis-Transplantation, University of Liège, CHU Sart Tilman, Liège, Belgium
| | - Emmanuelle Vidal-Petiot
- Department of Renal Physiology, Hôpital Bichat, AP-HP and Paris Diderot University, Paris, France
| | - Olivier Moranne
- Department of Nephrology-Dialysis-Transplantation, CHU Nice, Nice, France
| | - Christophe Mariat
- Department of Nephrology, University Jean Monnet, Saint-Etienne, France
| | | | - François Vrtovsnik
- Department of Nephrology, Hôpital Bichat, AP-HP and Paris Diderot University, Paris, France
| | - André-Jean Scheen
- Department of Diabetes, Nutrition and Metabolic Disorders, Department of Medicine, University of Liège, CHU Sart Tilman, Liège, Belgium
| | - Jean-Marie Krzesinski
- Department of Nephrology-Dialysis-Transplantation, University of Liège, CHU Sart Tilman, Liège, Belgium
| | - Martin Flamant
- Department of Renal Physiology, Hôpital Bichat, AP-HP and Paris Diderot University, Paris, France
| | - Pierre Delanaye
- Department of Nephrology-Dialysis-Transplantation, University of Liège, CHU Sart Tilman, Liège, Belgium
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MacIsaac RJ, Ekinci EI, Premaratne E, Lu ZX, Seah JM, Li Y, Boston R, Ward GM, Jerums G. The Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation does not improve the underestimation of Glomerular Filtration Rate (GFR) in people with diabetes and preserved renal function. BMC Nephrol 2015. [PMID: 26630928 DOI: 10.186/s12882-015-0196-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Our hypothesis was that both the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) equations would underestimate directly measured GFR (mGFR) to a similar extent in people with diabetes and preserved renal function. METHODS In a cross-sectional study, bias (eGFR - mGFR) was compared for the CKD-EPI and MDRD equations, after stratification for mGFR levels. We also examined the ability of the CKD-EPI compared with the MDRD equation to correctly classify subjects to various CKD stages. In a longitudinal study of subjects with an early decline in GFR i.e., initial mGFR > 60 ml/min/1.73 m(2) and rate of decline in GFR (ΔmGFR) > 3.3 ml/min/1.73 m(2) per year, ΔmGFR (based on initial and final values) was compared with ΔeGFR by the CKD-EPI and MDRD equations over a mean of 9 years. RESULTS In the cross-sectional study, mGFR for the whole group was 80 ± 2.2 ml/min/1.73 m(2) (n = 199, 75 % type 2 diabetes). For subjects with mGFR >90 ml/min/1.73 m(2) (mGFR: 112 ± 2.0, n = 76), both equations significantly underestimated mGFR to a similar extent: bias for CKD-EPI: -12 ± 1.4 ml/min/1.73 m(2) (p < 0.001) and for MDRD: -11 ± 2.1 ml/min/1.73 m(2) (p < 0.001). Using the CKD-EPI compared with the MDRD equation did not improve the number of subjects that were correctly classified to a CKD-stage. No biochemical or clinical patient characteristics were identified to account for the under estimation of mGFR values in the normal to high range by the CKD-EPI equation. In the longitudinal study (n = 30, 66 % type 1 diabetes), initial and final mGFR values were 102.8 ± 6 and 54.6 ± 6.0 ml/min/1.73 m(2), respectively. Mean ΔGFR (ml/min/1.73 m(2) per year) was 6.0 by mGFR compared with only 3.0 by MDRD and 3.2 by CKD-EPI (both p < 0.05 vs mGFR) CONCLUSIONS: Both the CKD-EPI and MDRD equations underestimate reference GFR values > 90 ml/min/1.73 m(2) as well as an early decline in GFR to a similar extent in people with diabetes. There is scope to improve methods for estimating an early decline in GFR.
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Affiliation(s)
- Richard J MacIsaac
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - Elif I Ekinci
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia. .,Menzies School of Health Research, Casuarina, 0811, Northern Territory, Australia. .,Department of Medicine, Austin Health, University of Melbourne, Heidelberg, 3084, Victoria, Australia.
| | - Erosha Premaratne
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia.
| | - Zhong X Lu
- Melbourne Pathology, Collingwood, 3066, Victoria, Australia.
| | - Jas-Mine Seah
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia.
| | - Yue Li
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - Ray Boston
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - Glenn M Ward
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Clinical Chemistry, St Vincent's Hospital Melbourne, Fitzroy, 3065, Victoria, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - George Jerums
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia. .,Department of Medicine, Austin Health, University of Melbourne, Heidelberg, 3084, Victoria, Australia.
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22
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MacIsaac RJ, Ekinci EI, Premaratne E, Lu ZX, Seah JM, Li Y, Boston R, Ward GM, Jerums G. The Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation does not improve the underestimation of Glomerular Filtration Rate (GFR) in people with diabetes and preserved renal function. BMC Nephrol 2015; 16:198. [PMID: 26630928 PMCID: PMC4668645 DOI: 10.1186/s12882-015-0196-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 11/25/2015] [Indexed: 12/18/2022] Open
Abstract
Background Our hypothesis was that both the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) equations would underestimate directly measured GFR (mGFR) to a similar extent in people with diabetes and preserved renal function. Methods In a cross-sectional study, bias (eGFR – mGFR) was compared for the CKD-EPI and MDRD equations, after stratification for mGFR levels. We also examined the ability of the CKD-EPI compared with the MDRD equation to correctly classify subjects to various CKD stages. In a longitudinal study of subjects with an early decline in GFR i.e., initial mGFR >60 ml/min/1.73 m2 and rate of decline in GFR (ΔmGFR) > 3.3 ml/min/1.73 m2 per year, ΔmGFR (based on initial and final values) was compared with ΔeGFR by the CKD-EPI and MDRD equations over a mean of 9 years. Results In the cross-sectional study, mGFR for the whole group was 80 ± 2.2 ml/min/1.73 m2 (n = 199, 75 % type 2 diabetes). For subjects with mGFR >90 ml/min/1.73 m2 (mGFR: 112 ± 2.0, n = 76), both equations significantly underestimated mGFR to a similar extent: bias for CKD-EPI: -12 ± 1.4 ml/min/1.73 m2 (p < 0.001) and for MDRD: -11 ± 2.1 ml/min/1.73 m2 (p < 0.001). Using the CKD-EPI compared with the MDRD equation did not improve the number of subjects that were correctly classified to a CKD-stage. No biochemical or clinical patient characteristics were identified to account for the under estimation of mGFR values in the normal to high range by the CKD-EPI equation. In the longitudinal study (n = 30, 66 % type 1 diabetes), initial and final mGFR values were 102.8 ± 6 and 54.6 ± 6.0 ml/min/1.73 m2, respectively. Mean ΔGFR (ml/min/1.73 m2 per year) was 6.0 by mGFR compared with only 3.0 by MDRD and 3.2 by CKD-EPI (both p < 0.05 vs mGFR) Conclusions Both the CKD-EPI and MDRD equations underestimate reference GFR values >90 ml/min/1.73 m2 as well as an early decline in GFR to a similar extent in people with diabetes. There is scope to improve methods for estimating an early decline in GFR.
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Affiliation(s)
- Richard J MacIsaac
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - Elif I Ekinci
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia. .,Menzies School of Health Research, Casuarina, 0811, Northern Territory, Australia. .,Department of Medicine, Austin Health, University of Melbourne, Heidelberg, 3084, Victoria, Australia.
| | - Erosha Premaratne
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia.
| | - Zhong X Lu
- Melbourne Pathology, Collingwood, 3066, Victoria, Australia.
| | - Jas-Mine Seah
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia.
| | - Yue Li
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - Ray Boston
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - Glenn M Ward
- Department of Endocrinology and Diabetes, St Vincent's Hospital Melbourne, 4th Floor, Daly Wing, 35 Victoria Parade, PO Box 2900, Fitzroy, VIC, 3065, Australia. .,Clinical Chemistry, St Vincent's Hospital Melbourne, Fitzroy, 3065, Victoria, Australia. .,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, 3065, Victoria, Australia.
| | - George Jerums
- Endocrine Centre, Austin Health, West Heidelberg, 3081, Victoria, Australia. .,Department of Medicine, Austin Health, University of Melbourne, Heidelberg, 3084, Victoria, Australia.
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Nyman U, Björk J, Bäck SE, Sterner G, Grubb A. Estimating GFR prior to contrast medium examinations—what the radiologist needs to know! Eur Radiol 2015; 26:425-35. [DOI: 10.1007/s00330-015-3842-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 05/05/2015] [Accepted: 05/11/2015] [Indexed: 11/25/2022]
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Eppenga WL, Kramers C, Derijks HJ, Wensing M, Wetzels JFM, De Smet PAGM. Individualizing pharmacotherapy in patients with renal impairment: the validity of the Modification of Diet in Renal Disease formula in specific patient populations with a glomerular filtration rate below 60 ml/min. A systematic review. PLoS One 2015; 10:e0116403. [PMID: 25741695 PMCID: PMC4351004 DOI: 10.1371/journal.pone.0116403] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 12/09/2014] [Indexed: 01/20/2023] Open
Abstract
Background The Modification of Diet in Renal Disease (MDRD) formula is widely used in clinical practice to assess the correct drug dose. This formula is based on serum creatinine levels which might be influenced by chronic diseases itself or the effects of the chronic diseases. We conducted a systematic review to determine the validity of the MDRD formula in specific patient populations with renal impairment: elderly, hospitalized and obese patients, patients with cardiovascular disease, cancer, chronic respiratory diseases, diabetes mellitus, liver cirrhosis and human immunodeficiency virus. Methods and Findings We searched for articles in Pubmed published from January 1999 through January 2014. Selection criteria were (1) patients with a glomerular filtration rate (GFR) < 60 ml/min (/1.73m2), (2) MDRD formula compared with a gold standard and (3) statistical analysis focused on bias, precision and/or accuracy. Data extraction was done by the first author and checked by a second author. A bias of 20% or less, a precision of 30% or less and an accuracy expressed as P30% of 80% or higher were indicators of the validity of the MDRD formula. In total we included 27 studies. The number of patients included ranged from 8 to 1831. The gold standard and measurement method used varied across the studies. For none of the specific patient populations the studies provided sufficient evidence of validity of the MDRD formula regarding the three parameters. For patients with diabetes mellitus and liver cirrhosis, hospitalized patients and elderly with moderate to severe renal impairment we concluded that the MDRD formula is not valid. Limitations of the review are the lack of considering the method of measuring serum creatinine levels and the type of gold standard used. Conclusion In several specific patient populations with renal impairment the use of the MDRD formula is not valid or has uncertain validity.
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Affiliation(s)
- Willemijn L. Eppenga
- Radboud University Medical Center, Radboud Institute for Health Sciences, IQ Healthcare, Nijmegen, The Netherlands
- * E-mail:
| | - Cornelis Kramers
- Radboud University Medical Center, Department of Pharmacology and Toxicology, Nijmegen, The Netherlands
- Department of Clinical Pharmacy, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands
| | - Hieronymus J. Derijks
- Hospital Pharmacy ‘ZANOB’, ‘s-Hertogenbosch, The Netherlands
- Division of Pharmacoepidemiology and Pharmacotherapy, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands
| | - Michel Wensing
- Radboud University Medical Center, Radboud Institute for Health Sciences, IQ Healthcare, Nijmegen, The Netherlands
| | - Jack F. M. Wetzels
- Radboud University Medical Center, Department of Nephrology, Nijmegen, The Netherlands
| | - Peter A. G. M. De Smet
- Radboud University Medical Center, Radboud Institute for Health Sciences, IQ Healthcare, Nijmegen, The Netherlands
- Radboud University Medical Center, Department of Pharmacy, Nijmegen, The Netherlands
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Lee SN, Shin DI, Jung MH, Choi IJ, Seo SM, Her SH, Kim PJ, Moon KW, Yoo KD, Baek SH, Seung KB. Impact of cystatin-C level on the prevalence and angiographic characteristics of vasospastic angina in Korean patients. Int Heart J 2014; 56:49-55. [PMID: 25742943 DOI: 10.1536/ihj.14-213] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Cystatin-C, a marker of mild renal dysfunction, has been reported to be associated with cardiovascular diseases including vasospastic angina (VSA). We aimed to investigate the impact of cystatin-C level on the prevalence and angiographic characteristics of VSA in Korean patients.A total of 549 patients in the VA-KOREA (Vasospastic Angina in KOREA) registry who underwent ergonovine provocation tests were consecutively enrolled. Estimated glomerular filtration rate (eGFR) and levels of serum creatinine (Cr) and cystatin-C were assessed before angiography.The patients were classified into two groups: the VSA group (n = 149, 27.1%) and the non-VSA group (n = 400). Although eGFR and Cr levels were similar between the two groups, the VSA group had a significantly higher level of cystatin-C (P < 0.05). A high level of cystatin-C (second tertile, hazard ratio 1.432; 95% confidence interval [1.1491.805]; P = 0.026, third tertile, 1.947 [1.132-2.719]; P = 0.003) and current smoking (2.710 [1.415-4.098]; P < 0.001) were independently associated with the prevalence of VSA. Furthermore, the highest level of cystatin-C (> 0.96 ng/mL) had a significant impact on the incidence of multivessel spasm (2.608 [1.061-4.596]; P = 0.037).A high level of cystatin-C was independently associated with the prevalence of VSA and with a high-risk type of VSA in Korean patients, suggesting that proactive investigation of VSA should be considered for patients with mild renal dysfunction indicated by elevated cystatin-C.
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Affiliation(s)
- Su Nam Lee
- Department of Cardiovascular Medicine, The Catholic University of Korea
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Fotheringham J, Weatherley N, Kawar B, Fogarty DG, Ellam T. The body composition and excretory burden of lean, obese, and severely obese individuals has implications for the assessment of chronic kidney disease. Kidney Int 2014; 86:1221-8. [PMID: 24717300 DOI: 10.1038/ki.2014.112] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 02/17/2014] [Accepted: 02/27/2014] [Indexed: 11/09/2022]
Abstract
Obesity could affect associations between creatinine generation, estimated body surface area, and excretory burden, with effects on chronic kidney disease assessment. We therefore examined the impact of obesity on the performances of estimated glomerular filtration rate (eGFR), the urine albumin:creatinine ratio (ACR), and excretory burden in 3611 participants of the Chronic Renal Insufficiency Cohort. Urine creatinine excretion significantly increased with body mass index (BMI) (34 and 31% greater at 40 kg/m(2) or more versus the normal of 18.5-25 kg/m(2)) in men and women, respectively, such that patients with a normal BMI and an ACR of 30 mg/g had the same 24-h albuminuria as severely obese patients with ACR 23 mg/g. The bias of eGFR (referenced to body surface area-indexed iothalamate (i-)GFR) had a U-shaped relationship to obesity in men but progressively increased in women. Nevertheless, obesity-associated body surface area increases were accompanied by a greater absolute (non-indexed) iGFR for a given eGFR, particularly in men. Two men with eGFRs of 45 ml/min per 1.73 m(2), height 1.76 m, and BMI 22 or 45 kg/m(2) had absolute iGFRs of 46 and 62 ml/min, respectively. The excretory burden, assessed as urine urea nitrogen and estimated dietary phosphorus, sodium, and potassium intakes, also increased in obesity. However, obese men had lower odds of anemia, hyperkalemia, and hyperphosphatemia. Thus, for a given ACR and eGFR, obese individuals have greater albuminuria, absolute GFR, and excretory burden. This has implications for chronic kidney disease management, screening, and research.
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Affiliation(s)
- James Fotheringham
- 1] Sheffield Kidney Institute, Northern General Hospital, Sheffield, UK [2] School of Health and Related Research, University of Sheffield, Sheffield, UK
| | | | - Bisher Kawar
- Sheffield Kidney Institute, Northern General Hospital, Sheffield, UK
| | - Damian G Fogarty
- Regional Nephrology Unit, Belfast Health and Social Care Trust, Belfast, UK
| | - Timothy Ellam
- 1] Sheffield Kidney Institute, Northern General Hospital, Sheffield, UK [2] Department of Cardiovascular Science, University of Sheffield, Sheffield, UK
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