Glomerular Filtration Rate Index Research Articles

Effect of indexed glomerular filtration rate according to age.

To find out up to what age there is dispersion in glomerular filtration rate (GFR) values when normalised by body surface area (BSA) and extracellular fluid volume (ECFV), based on the hypothesis that these values differ in childhood age. A retrospective study was performed on patients aged 0-85years, with renal pathology, who were administered i.v. 51Cr-EDTA. GFR was obtained using the Ham and Piepsz (children) or Christensen and Groth (adults) formula. Results were normalised by BSA and ECFV. The cut-off point is defined as the age that discriminates between values ± 10 points apart. Using a ROC curve analysis, this age was set at 11.96years with a sensitivity of 0.83 and a specificity of 0.85. The area obtained was 0.902 (95%CI 0.880-0.923). The results were corroborated by linear regression stratifying by age. For children under 12years of age, the Pearson correlation was 0.883 (95% CI 0.860-0.902). For those aged 12years or older, this coefficient was 0.963 (95%CI 0.957-0.968). According to our results, when normalising GFR by BSA and by ECFV there are different behaviours according to age. For children older than 12years both normalisation methods can be used, but for children younger than 12years there are differences. We believe that in children under 12years of age, GFR should be normalised by ECFV.

Relationship of Decayed, Missing, Filled, Teeth and Related Indexes of Glomerular Filtration Rate in Various Stages of Chronic Kidney Disease in Adults Residing in Shahedieh City, Yazd Province

Introduction: Oral health problems in patients with chronic renal failure can endanger their systemic health. The aim of this study was to assess the correlation of Decayed, Missing, Filled, Teeth (DMFT) and Glomerular Filtration Rate (GFR). Materials & Methods: In this descriptive-analytical study, using the Shahidieh project conducted on 9000 people from the city of Yazd in 2017 for data collection. The serum creatinine level, and age, gender and weight of patients were extracted from the questionnaire designed for the Yazd Shahedieh Project after receiving permission. The GFR of each individual was calculated using the Cockcroft Gault formula. For assessment of oral health status, the DMF index of permanent teeth of adults was calculated. The Data analyzed using t-test, ANOVA, Pearson’s correlation coefficient, and regression analysis. Results: Weight was not related to the number of carious teeth but was directly related to the number of filled teeth. Weight was also inversely related to the number of missing teeth and DMFT. Serum creatinine was not related to the number of decayed teeth but was directly related to the number of missing teeth and DMFT. Serum creatinine was inversely related to the number of filled teeth. Age was inversely related to the number of decayed and filled teeth, but was directly related to the number of missing teeth and DMFT. GFR is directly related to the number of decayed and filled teeth, but is inversely related to the number of missing teeth and DMFT. GFR and DMFT index had a significant and inverse relationship. Conclusion: According to the present study the lower GFR index and the higher the serum creatinine and the higher the stage of kidney disease, a direct correlation of a high DMFT index was observed.

25-LB: Peripheral Neuropathy and Associated Factors in Patients with Type 2 Diabetes Mellitus in Vietnam—A Cross-Sectional Study

Peripheral neuropathy and associated factors in patients with type 2 diabetes mellitus in Vietnam: A cross-sectional study Diabetes peripheral neuropathy (DPN) is the most common complication associated with diabetes mellitus. We aimed to establish the characteristic and associated factors of DPN in Vietnam. In total, 140 patients with type 2 diabetes mellitus (T2DM) were screened and enrolled consecutively over a six month period at the endocrinology department in 103 Military hospital. Questionnaires, demographic details, clinical examination, and blood tests were used to collect data from all patients. DPN was evaluated using diabetes neuropathy symptom score and nerve conduction study. Potential factors related to DPN were explored including body mass index, years with disease (<10 vs. ≥10 years) , glycemic control (HbA1C <7.5% vs. ≥ 7.5%) , glomerular filtration rate (GFR) , lipid profile. The prevalence of DPN was 43.5% (61/140) in the number of patients with T2DM. The main manifestation of peripheral nerve damage in subject is numbness 54,1%, decreased rough touch 52,56%. The majority of patients did not have movement disorders 95.08% and normal sense of deep sensation 93,4%. The percentage of patients with a burning sensation, reduction in raw tactile and movement disorders was higher in the group with duration of disease over 10 years (n=23) , compared to the group less than 10 years (n=38) (p <0.05) . The neurotransmitter index in the group of patients with HbA1C ≥ 7.5% (n=17) was significantly different compared to the group with HbA1C < 7.5% (n=44) (p < 0.05) . The group with GFR <70 ml/ph/1.73m2 (n=12) showed the significant change in nerve conduction parameters compared to the group with GFR ≥ 70 ml/ph/1.73m2 (n=49) (p < 0.05) . DPN is highly frequent among patients with T2DM in Vietnam. Associated factors to DPN included duration of disease, HbA1C level and GFR index. The good glycemic control and early clinical manifestation as well as evaluating the kidney function would play an important role in this problem. Disclosure N. T. T. Trang: None. T. Fong: None. T. D. Do: None.

The influence of birth weight and gestational age on kidney function in premature infants

Introduction. The impact of prematurity on the functional state of the kidneys in infants has not yet been sufficiently studied. Aim. To determine the influence of birth weight and gestational age on the creatinine level in the blood and glomerular filtration rate (GFR) in early childhood. Materials and methods. A retrospective analysis was conducted on medical records of 316 children aged from 1 month to 1.5 years, hospitalized at the Department of Early Childhood Pathology (National Medical Research Center for Children’s Health, Moscow) from 2012 to 2020 due to consequences of perinatal CNS damage. Children without congenital kidney diseases, with normal urine values in medical history, without structural abnormalities on ultrasound were included in this study. Serum creatinine was determined by the enzymatic method, GFR - by the Schwartz’s formula using a coefficient of 0.413, as well as, previously proposed coefficients of 0.33 for premature and 0.44 for full-term infants. Results. In premature infants, notably born with extremely low birth weight and very low birth weight, at the age of 1 year, serum creatinine is reduced compared to full-term infants, GFR in deep-premature infants exceeds the level of GFR in full-term infants by the year. The results allow concluding the method of calculating GFR by formulas based on serum creatinine to be invalid. Due to possible hyperfiltration in preterm infants, they need regular monitoring urine tests, blood pressure, due to the risk of developing chronic kidney disease. Conclusions. It is necessary to search for other methods for determining GFR in extremely premature infants. The established indices of the blood creatinine content can be used as reference values for different periods of gestation and body weight at birth in institutions using the enzymatic method for determining blood creatinine. The obtained GFR indices as a reference can be recommended for full-term and premature babies born after 32 weeks of gestation and with a birth weight of more than 1500 g.

Cross-Sectional and Longitudinal Performance of Creatinine- and Cystatin C-Based Estimating Equations Relative to Exogenously Measured Glomerular Filtration Rate in HIV-Positive and HIV-Negative Persons.

Reliable estimates of glomerular filtration rate (GFR) are important in the clinical management of HIV-positive patients. Data on the performance of widely used estimating equations (eGFR) relative to exogenously measured GFR are sparse in this population. We evaluated cross-sectional and longitudinal accuracy and bias of eGFR, based on creatinine and cystatin C, relative to disappearance of infused iohexol from plasma (iGFR) in a cohort of participants followed annually for up to 7 years. A total of 222 HIV-positive and 139 HIV-negative participants contributed 1240 visits with valid iGFR and eGFR measures. Estimated GFR based on both creatinine and cystatin C performed the best. Estimated GFR based on creatinine alone overestimated iGFR by 9 mL·min·1.73 m on average and was significantly less accurate in HIV-positive than HIV-negative individuals. The performance of equations based on either creatinine alone or cystatin C alone were significantly affected by participant factors (eg, non-suppressed HIV RNA, nadir CD4 count, hepatitis C virus coinfection). The average iGFR slope was -4% per year in HIV-positive participants. In both HIV-positive and HIV-negative participants, eGFR slope measures were generally unbiased but inaccurate, with only 60%-74% of observations falling within ±5% points of iGFR slope. Both creatinine and cystatin C have limitations as GFR indices in HIV-positive individuals. Estimated GFR based on both creatinine and cystatin C performed best in our study and may be preferred in HIV-positive persons with kidney disease or comorbidities that place them at high risk for kidney disease.

Performance of Glomerular Filtration Rate Estimating Equations Before and After Bariatric Surgery

Rationale & ObjectiveEvaluation 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 DesignProspective observational study.Setting & Participants27 adults with body mass index (BMI) ≥ 35 kg/m2 who underwent measurement of GFR before and after bariatric surgery.OutcomesIndexed 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 ApproachBias and percent of estimates within 20% and 30% of mGFR (P20 and P30) for estimating equations were examined.ResultsMean 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.LimitationsSmall, mostly white sample.ConclusionsChanges 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.

Kidney Function in Obesity-Challenges in Indexing and Estimation.

As the prevalence of obesity continues to increase worldwide, an increasing number of people are at risk for kidney disease. Thus, there is a critical need to understand how best to assess kidney function in this population, and several challenges exist. The convention of indexing glomerular filtration rate (GFR) to body surface area (BSA) attempts to normalize exposure to metabolic wastes across populations of differing body size. In obese individuals, this convention results in a significantly lower indexed GFR than unindexed GFR, which has practical implications for drug dosing. Recent data suggest that "unindexing" estimated GFR (multiplying by BSA/1.73m2) for drug dosing may be acceptable, but pharmocokinetic data to support this practice are lacking. Beyond indexing, biomarkers commonly used for estimating GFR may induce bias. Creatinine is influenced by muscle mass, whereas cystatin C correlates with fat mass, both independent of kidney function. Further research is needed to evaluate the performance of estimating equations and other filtration markers in obesity, and determine whether unindexed GFR might better predict optimal drug dosing and clinical outcomes in patients whose BSA is very different than the conventional normalized value of 1.73m2.

Therapeutic Effects of Albendazole on Kidney Functions and Urinary Excretion of Florfenicol in Goats

Therapeutic effects of albendazole on kidney functions and urinary excretion of florfenicol was determined in goats. After restraining the animals, 600 mg dose of florfenicol was administered intramuscularly. Blood and urine samples were collected, at different time intervals, post-medication. After a washout period of 7 days, florfenicol was administrated along with a 150 mg dose of albendazole. Blood and urine samples were collected at similar time intervals as done previously. Serum was separated by centrifugation and both serum and urine samples were stored at -20ºC until analysis. Drug concentration in samples was determined by using HPLC method. Endogenous creatinine is used as an index of GFR (glomerular filtration rate) and was estimated both in serum and urine samples. Concentrations of drug and creatinine were used to calculate the renal clearance and urinary excretion. Calculated Mean ± SE of renal clearance of florfenicol was 3.32 ± 0.60 and 3.90 ± 0.52 ml/min/kg when given alone and along with albendazole respectively. Influence of serum concentration, diuresis and urinary pH on renal clearance was determined by least square regression/ correlation analysis. Mean ± SEM of urinary excretion expressed as cumulative percent of dose excreted in the urine of goats was 35.81 ± 2.47 and 37.48 ± 2.60, when florfenicol was given alone and along with albendazole respectively. Conclusion and Results were analyzed by student “t” test and it is concluded that there is significant drug- drug interaction between florfenicol and albendazole.

Evaluation value of functional magnetic resonance urography on unilateral renal function in children with hydronephrosis

Objective To assess the value of functional magnetic resonance urography (fMRU) for the unilateral renal function in children with hydronephrosis. Methods Fourteen children with congenital hydronephrosis (unilateral hydronephrosis in 12 cases, bilateral hydronephrosis in 2 cases) examined by fMRU in Beijing Children′s Hospital, Capital Medical University, were enrolled.In 7 patients of them, diuretic renal scintigraphy (DRS) was performed within 10 days before fMRU examination.The following parameters in fMRU, as renal parenchymal volume, volumetric differential renal function (vDRF), Patlak, Patlak differential renal function (pDRF), index of glomerular filtration rate (GFR) and differential renal function based on index of GFR (gDRF), were calculated and analyzed.Statistical analysis was performed by using SPSS 13.0. Results In 7 cases whose fMRU and DRS were examined, the indexes of GFR obtained from fMRU and GFR from DRS were well correlated (r=0.892, P<0.001) in 14 kidneys.The gDRF determined by 2 methods on the left kidneys[the average was(46.80±19.20)% and(45.18±20.29)%, respectively] had no significant difference (t=0.051 6, P=0.624), which was also highly correlated (r=0.912, P=0.004). In 12 cases with unilateral hydronephrosis, vDRF, pDRF, index of GFR and gDRF in hydronephrotic side[(43.54±9.61)%, (42.80±10.83)%, (38.56±29.23) mL/min, (38.37±13.61)%] were all less than those in the contralateral side[(56.46±9.61)%, (57.19±10.83)%, (57.02±26.22) mL/min, (61.63±13.61)%](t=2.326, 2.300, 2.422, 2.960; P=0.040, 0.042, 0.034, 0.013). However, there was no statistical difference in both renal parenchymal volume and Patlak between the hydronephrotic and the contralateral side kidneys(t=1.765, 1.450; P=0.105, 0.175). Conclusions fMRU is a very valuable examination method in evaluating single kidney function in children with congenital hydronephrosis, and able to demonstrate that gDRF, indexes of GFR, vDRF and pDRF decrease in the hydronephrotic kidney. Key words: Magnetic resonance urography; Hydronephrosis; Glomerular filtration rate; Child

Glomerular Filtration Rate in Healthy Living Potential Kidney Donors: A Meta-Analysis Supporting the Construction of the Full Age Spectrum Equation

Background: Normal kidney function or, more specifically, normal glomerular filtration rate (GFR) in men and women and its decline with age is still much debated today. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation has gender (and race) multiplication factors, accounts for a decline that starts at very young age and assumes that the mean GFR is as high as 120-130 ml/min/1.73 m² from a young age. The full age spectrum (FAS) estimated mean GFR is about 107 ml/min/1.73 m² at a young age and remains constant until the age of 40 years and then starts to decline both in men and women. The aim of this research study was to give more insight into ‘normal' GFR levels and the physiological decrease of kidney function with age and to use a meta-analysis to evaluate the mathematical construction of the FAS and the CKD-EPI equation. Methods: We conducted a meta-analysis of published GFR measurements in healthy Caucasian living potential kidney donors (n = 5,482, 46.8% men). Only publications dating from 2000 were selected to avoid the possible influence of body surface area changes in the last decades on the indexed GFR, expressed in ml/min/1.73 m². Results: We found that the mean GFR ≈ 107 ml/min/1.73 m² up to the age of 40 years, but renal decline begins beyond 40 years. No evidence could be found for any difference between men and women in the separate age groups. Conclusions: The current meta-analysis supports the mathematical form of the FAS equation, which matches the age/sex dependency of measured GFR for healthy potential living kidney donors.

Japanese society for dialysis therapy clinical guideline for "hemodialysis initiation for maintenance hemodialysis".

Yuzo Watanabe, Kunihiro Yamagata, Shinichi Nishi, Hideki Hirakata, Norio Hanafusa, Chie Saito, Motoshi Hattori, Noritomo Itami, Yasuhiro Komatsu, Yoshindo Kawaguchi, Kazuhiko Tsuruya, Yoshiharu Tsubakihara, Kazuyuki Suzuki, Ken Sakai, Hideki Kawanishi, Daijo Inaguma, Hiroyasu Yamamoto, Yoshiaki Takemoto, Noriko Mori, Kazuyoshi Okada, Hiroshi Hataya, Takashi Akiba, Kunitoshi Iseki, Tadashi Tomo, Ikuto Masakane, Tadao Akizawa, and Jun Minakuchi, for “Hemodialysis Initiation for Maintenance Hemodialysis” Guideline Working Group, Japanese Society for Dialysis Therapy

Agreement among measurements and estimations of glomerular filtration in children with cancer

Glomerular filtration is an important route of elimination for many types of chemotherapy. Accurate estimation of glomerular filtration at the bedside is essential in the management of children with cancer. Bedside formulae for the estimation of glomerular filtration have not been validated in children with cancer. We investigated the accuracy of three formulae (the original Schwartz, Counahan-Barratt, and revised Schwartz equations) against measurement of the glomerular filtration rate (GFR) in a cohort of children with cancer. This was a retrospective review of existing data from a single institution. The electronic medical record was queried for subjects meeting inclusion criteria during a 3.5 year time frame. Bland-Altman analyses were used to assess agreement among current formulae and estimating the GFR compared to the measured, or index GFR. Logistic regression was performed to identify potential variables with an effect on the estimation of GFR. None of the three estimation formulae provided a reliable estimate of the index GFR. The mean difference was lowest between the revised Schwartz and the index GFR compared to the other two formulae and the index GFR. For the original Schwartz equation, age and prior receipt of chemotherapy were significant predictors of under- and overestimation. For the revised Schwartz equation, one age group (6-12 years) and a diagnosis of neuroblastoma actively receiving chemotherapy were positive risk factors for overestimation of the GFR. Currently available estimation formulae for GFR may not be appropriate for children with cancer.

Indexing Glomerular Filtration Rate to Body Surface Area: Clinical Consequences

Kidney function is mostly expressed in terms of glomerular filtration rate (GFR). A common feature is the expression as ml/min per 1.73 m(2) , which represents the adjustment of the individual kidney function to a standard body surface area (BSA) to allow comparison between individuals. We investigated the impact of indexing GFR to BSA in cancer patients, as this BSA indexation might affect the reported individual kidney function. Cross-sectional study of 895 adults who had their kidney function measured with (51) chrome ethylene diamine tetraacetic acid. Mean values of BSA-indexed GFR vs. mean absolute GFR were analyzed with a t-test for paired data. Bland-Altman plot was used to analyze agreement between the indexed and absolute GFR values. BSA-GFR in patients with a BSA <1.60 m(2) overestimated GFR with a bias of 10.08 ml/min (11.46%) and underestimated GFR in those with a BSA >2 m(2) with a bias up to -20.76 ml/min (-23.59%). BSA is not a good normalization index (NI) in patients with extreme body sizes. Therefore, until a better NI is found, we recommend clinicians to use the absolute GFR to calculate individual drug chemotherapy dosage as well as express individual kidney function.

Kidney Transplant Donor Glomerular Filtration Rate by Iohexol Clearance During Computerized Tomographic Angiography of the Kidneys

BackgroundPre-transplantation living-donor kidney function determines remaining donor kidney function and significantly affects post-transplantation allograft function in the recipient. Few transplantation centers perform donor kidney function measurement owing to patient burden. A simplified method of glomerular filtration rate (GFR) measurement after angiographic procedures may facilitate more precise measurement of donor kidney function. MethodsWe evaluated the agreement between a simplified method of GFR measurement after renal computerized tomographic (CT) angiography (index GFR, 100 mL iohexol [350 mg/mL iodine]) and the reference GFR measurement with the use of iodinated radiocontrast media (5 mL bolus of iohexol [300 mg/mL iodine]) among 19 potential living kidney transplant donors. The 24-hour creatinine clearance and GFR estimation equations were additionally examined. Kidney lengths and total and segmented cortical kidney volumes were also measured. ResultsThe index CT angiography GFR performed best with respect to the reference GFR with minimal bias (mean difference, −4 mL/min/1.73 m2), good precision (SD of the difference, 9.8 mL/min/1.73 m2), coefficient of determination (R2) of 0.74, narrow mean coefficient of variation (5% [range 1%–15%]), and high accuracy, with 100% of the values for the index test within 30% of the reference test. The 24-hour urine creatinine clearance values performed poorly. Kidney volumes and length did not significantly correlate with measured GFR. ConclusionsThe CT angiographic GFR measurement could be a useful and more convenient method of donor kidney function evaluation and maintains minimal bias, high precision, and accuracy compared with the reference GFR measurement.

Sequential assessment of glomerular filtration rate (GFR) during development of hypertension in freely moving Dahl salt‐sensitive rats

A new method for sequential measurement of GFR was applied during the development of hypertension in the conscious Dahl salt‐sensitive (SS) rat. Utilizing a miniaturized device (Kidney Int. 79: 1254, 2011), disappearance curves of fluorescein isothiocyanate (FITC)‐sinistrin were determined by transcutaneous excitation and real time detection of the emitted light through the skin. Two groups of SS rats with implanted femoral venous and carotid catheters were studied before (LS; 0.4% NaCl) and on days 2,5,7,14 and 21 after switching to 4.0% (HS) diet (n=9) or maintaining on LS (n=6). SS rats maintained on LS exhibited no significant changes in mean arterial pressure (MAP; telemetry) or GFR while in the group fed HS, GFR decreased progressively and significantly from 1.52±0.07 (T1/2=21±0.9 min) to 1.1±0.04 ml/min/100g bwgt (28.4±1.1 min.) by d21. MAP increased during this period from 132±2 to 162±7 mmHg in the HS group. In contrast, creatinine clearance (urine and plasma determined by MS), the traditional index of GFR, did not change in either group. In conclusion, this novel non‐invasive method using sinistrin provides a sensitive approach for repetitive tracking of GFR in freely moving rats during disease progression and is more sensitive than standard measurements of creatinine clearance. The data clearly show progressive reduction of GFR in SS rats as salt‐induced hypertension developed.

Evaluation of Serum Creatinine Concentration–Based Glomerular Filtration Rate Equations in Pediatric Patients with Chronic Kidney Disease

To evaluate the accuracy of four equations based on serum creatinine concentration-the original Schwartz equation and the Leger, Bedside Chronic Kidney Disease in Children (CKiD), and Counahan-Barratt equations-for determining glomerular filtration rate (GFR) in pediatric patients with chronic kidney disease. Retrospective, observational, cross-sectional study. Single-center, academic, outpatient pediatric nephrology clinic. Fifty-three pediatric patients with stages 2-5 chronic kidney disease who completed GFR assessment with (125) I-iothalamate between January 2002 and January 2005. Data were collected from each patient's medical record. Glomerular filtration rate data were analyzed using 59 evaluations from the 53 pediatric patients. (125) I-iothalamate clearance was used as the index GFR. The Bedside CKiD and Counahan-Barratt equations outperformed the Schwartz and Leger equations when the index GFR wasless than60 ml/minute/1.73 m(2) ; the Schwartz and Counahan-Barratt equations performed best for index GFRs of 60 ml/minute/1.73 m(2) or greater. Overestimation was highest with the Schwartz and Leger equations (> 20% index GFR in 57.6% and 62.7% of patients, respectively). Underestimation was highest with the Bedside CKiD and Counahan-Barratt equations (> 20% index GFR in 30.5% and 28.8%, respectively). The new Bedside CKiD equation performed well for pediatric patients with moderate-to-severe chronic kidney disease, but less well for pediatric patients with mild disease. Additional studies are needed to develop more precise GFR equations using serum creatinine concentration.

822 NOVEL APPROACHES TO PREVENTION OF CHRONIC KIDNEY DISEASE IN PATIENTS WITH METABOLIC SYNDROME

Metabolic syndrome (MS) is a major public health threat. Individuals with MS are at increased risk for development of chronic kidney disease (CKD). Despite effective medical interventions that have targeted vascular renin-angiotensin system (RAS) blockade the prevalence of CKD remains considerably high. Few studies have directly compared the reno- protective effects of Angiotensin II-receptor blockers and Angiotensin-converting- enzyme inhibitors (ACE) in patients with MS. The aim of the present study was to compare the renoprotective effects of Angiotensin II-receptor blockers and Angiotensin-converting-enzyme inhibitors (ACE) in patients with MS and early nephropathy. In this prospective three year study, we randomly assigned 123 patients (mean age 45.8±11.7 years, range 31-57 years, 72 male and 51 female) with metabolic syndrome and early nephropathy to receive either the ACE inhibitor Quinapril (Accupro, Pfizer International, 20mg daily, 43 subjects) or Angiotensin II- receptor blocker Valsartan (Diovan, Novartis, 160 mg daily, in 41 subjects) or in combination Valsartan / Quinapril (160 mg/20 mg daily, in 39 subjects). The endpoint was the change in the glomerular filtration rate (GFR) (determined by measuring the plasma Clearance of Creatinine) between the baseline value and the last available value during the three-year treatment. After three years, indices of GFR increased by 4.2 ml/min/1.73m² in Quinapril-treated patients, compared with - 4.7 ml/min/1.73m² in Valsartan-treated subjects, and - 7.1 ml /min/ 1.73m² in Valsartan /Quinapril group (p<0.01). The results indicated that Valsartan was not superior to Quinapril, but the renoprotective effects of the combined therapy with Valsartan/Quinapril significantly improved after three years. © 2011 Bull. Georg. Natl. Acad. Sci.

Marked Association Between Obesity and Glomerular Hyperfiltration: A Cross-sectional Study in an African Population

Obesity and African American ethnicity are established independent risk factors for the development of chronic kidney disease. No data exist about the association between obesity and renal hemodynamics in the African region. Cross-sectional study. 301 nondiabetic participants (97 lean, 108 overweight, and 96 obese) of African descent with a positive family history of hypertension from the Seychelles islands. Body mass index (BMI). Glomerular hyperfiltration, glomerular filtration rate (GFR), effective renal plasma flow (ERPF), and filtration fraction. GFR and ERPF were measured using inulin and para-aminohippurate clearances, respectively. Participants' baseline demographics, laboratory data, and blood pressure were measured using standard techniques. The prevalence of glomerular hyperfiltration (defined as GFR >or=140 mL/min) increased across BMI categories (7.2%, 14.8%, and 27.1% for lean, overweight, and obese participants, respectively; P < 0.001). Higher BMI was associated with higher median GFR (99, 110, and 117 mL/min for lean, overweight, and obese participants, respectively; P < 0.001), ERPF (424, 462, and 477 mL/min, respectively; P = 0.01), and filtration fraction (0.23, 0.24, and 0.25; P < 0.001). Multivariate analyses adjusting for age, sex, blood pressure, fasting glucose level, and urinary sodium excretion and accounting for familial correlations confirmed the associations between high BMI (>25 kg/m(2)) and increased GFR, ERPF, and filtration fraction. No association between BMI categories and GFR was found with adjustment for body surface area. Participants had a positive family history of hypertension. Overweight and obesity are associated with increased GFR, ERPF, and filtration fraction and a high prevalence of glomerular hyperfiltration in nondiabetic individuals of African descent. The absence of associations between BMI categories and GFR indexed for body surface area raises questions regarding the appropriateness of indexing GFR for body surface area in overweight populations.

Errors induced by indexing glomerular filtration rate for body surface area: reductio ad absurdum

Errors induced by indexing glomerular filtration rate for body surface area: reductio ad absurdum

Indexation du débit de filtration glomérulaire par la surface corporelle : mythe et réalité

Indexing glomerular filtration rate (GFR) for body surface area (BSA) is often realized without arising any questions. However, physiological basis for such an indexation are very poor. Indeed, indexing GFR for BSA to avoid variation due to differences in body size necessarily implies that GFR is a linear function of BSA and that the intercept of this linear function is zero. Moreover, when GFR is indexed for BSA, the relation indexed GFR-BSA must completely disappear. These physiological prerequisites are not found for BSA indexation. We will review the history of this indexation and will underline errors and defaults. Different equations to estimate BSA exist and will be discussed. The choice of "1.73m(2)" will be also criticized. Moreover, indexing GFR for BSA has little impact on GFR results in "normal" body size population. Nevertheless, this indexation will have strong consequences in very lean (such as anorexia) and in obese patients. We will discuss possible alternatives proposed to substitute for BSA indexation.