Estimated Glomerular Filtration Rate Research Articles

Prevalence of impaired renal function among childless men as compared to fathers: a population-based study

Male reproductive impairment has been linked with an increased risk of numerous non-communicable diseases. Yet, epidemiological data on renal disease among subfertile men is scarce. Therefore, by using male childlessness as a proxy for male infertility, we aimed to investigate its association with renal function. Data was sourced from a population-based cohort including 22,444 men. After exclusion of men aged < 45 years (n = 10,842), the remaining men were divided into two groups: these being childless (n = 5494) and fathers (n = 6108). Logistic regression was applied to explore the association between male childlessness and renal impairment. Childless men as compared to fathers, were more likely to have an estimated-glomerular filtration rate < 60 ml/min/1.73m2 (OR 1.36, 95 CI 1.08–1.70; p = 0.008). After adjustment for age, marital status, smoking habits, diabetes, hypertension and other components of metabolic syndrome, childless men were also more likely to have dipstick proteinuria (OR 1.85, 95 CI 1.16–2.95; p = 0.01). With the growing panorama of disease associated with male reproductive impairment, men with fertility issues may constitute a target population with potential benefit from closer follow-up of their renal function.

Bias and Accuracy of Glomerular Filtration Rate Estimating Equations in the US

There is increasing concern that continued use of a glomerular filtration rate (GFR) estimating equation adjusted for a single racial group could exacerbate chronic kidney disease-related disparities and inequalities. To assess the performance of GFR estimating equations across varied patient populations. PubMed, Embase, Web of Science, ClinicalTrials.gov, and Scopus databases were systematically searched from January 2012 to February 2023. Inclusion criteria were studies that compared measured GFR with estimated GFR in adults using established reference standards and methods. A total of 6663 studies were initially identified for screening and review. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 2 authors independently extracted data on studies that examined the bias and accuracy of GFR estimating equations. For each outcome, a random-effects model was used to calculate pooled estimates. Data analysis was conducted from March to December 2023. The primary outcomes were bias and accuracy of estimated GFRs in Black vs non-Black patients, as well as in individuals with chronic conditions. Bias was defined as the median difference between the measured GFR and the estimated GFR. Accuracy was assessed with P30 (the proportion of persons in a data set whose estimated GFR values were within 30% of measured GFR values) and measures of heterogeneity. A total of 12 studies with a combined 44 721 patients were included. Significant heterogeneity was found in the bias of various GFR estimation equations. Race-corrected equations and creatinine-based equations tended to overestimate GFR in Black populations and showed mixed results in non-Black populations. For creatinine-based equations, the mean bias in subgroup analysis was 2.1 mL/min/1.73 m2 (95% CI, -0.2 mL/min/1.73 m2 to 4.4 mL/min/1.73 m2) in Black persons and 1.3 mL/min/1.73 m2 (95% CI, 0.0 mL/min/1.73 m2 to 2.5 mL/min/1.73 m2) in non-Black persons. Equations using only cystatin C had small biases. Regarding accuracy, heterogeneity was high in both groups. The overall P30 was 84.5% in Black persons and 87.8% in non-Black persons. Creatinine-based equations were more accurate in non-Black persons than in Black persons. For creatinine-cystatin C equations, the P30 was higher in non-Black persons. There was no significant P30 difference in cystatin C-only equations between the 2 groups. In patients with chronic conditions, P30 values were generally less than 85%, and the biases varied widely. This systematic review and meta-analysis of GFR estimating equations suggests that there is bias in race-based GFR estimating equations, which exacerbates kidney disease disparities. Development of a GFR equation independent of race is a crucial starting point, but not the sole solution. Addressing the disproportionate burden of kidney failure on Black individuals in the US requires an enduring, multifaceted approach that should include improving diagnostics, tackling social determinants of health, confronting systemic racism, and using effective disease prevention and management strategies.

Comparison of estimated GFR using cystatin C versus creatinine in pediatric kidney transplant recipients

BackgroundAn accurate, rapid estimate of glomerular filtration rate (GFR) in kidney transplant patients affords early detection of transplant deterioration and timely intervention. This study compared the performance of serum creatinine (Cr) and cystatin C (CysC)-based GFR equations to measured GFR (mGFR) using iohexol among pediatric kidney transplant recipients.MethodsCysC, Cr, and mGFR were obtained from 45 kidney transplant patients, 1–18 years old. Cr- and CysC-estimated GFR (eGFR) was compared against mGFR using the Cr-based (Bedside Schwartz, U25-Cr), CysC-based (Gentian CysC, CAPA, U25-CysC), and Cr-CysC combination (CKiD Cr-CysC, U25 Cr-CysC) equations in terms of bias, precision, and accuracy. Bland–Altman plots assessed the agreement between eGFR and mGFR. Secondary analyses evaluated the formulas in patients with biopsy-proven histological changes, and K/DOQI CKD staging.ResultsBias was small with Gentian CysC (0.1 ml/min/1.73 m2); 88.9% and 37.8% of U25-CysC estimations were within 30% and 10% of mGFR, respectively. In subjects with histological changes on biopsy, Gentian CysC had a small bias and U25-CysC were more accurate—both with 83.3% of and 41.7% of estimates within 30% and 10% mGFR, respectively. Precision was better with U25-CysC, CKiD Cr-CysC, and U25 Cr-CysC. Bland–Altman plots showed the Bedside Schwartz, Gentian CysC, CAPA, and U25-CysC tend to overestimate GFR when > 100 ml/min/1.72 m2. CAPA misclassified CKD stage the least (whole cohort 24.4%, histological changes on biopsy 33.3%).ConclusionsIn this small cohort, CysC-based equations with or without Cr may have better bias, precision, and accuracy in predicting GFR.Graphical abstractA higher resolution version of the Graphical abstract is available as Supplementary information

The highlights in nephrology in 2023

This article aims to summarize the “Quoi de neuf en néphrologie?” session held at the 2023 SFNDT Congress in Liège and sessions focused on updates regarding IgA nephropathy (NIgA) and ANCA-associated vasculitis. The agenda for the nephrology “Quoi de neuf en néphrologie?” session this year was to review key publications from non-nephrology journals, discussing topics such as nephroprotection, treatment of glomerulopathies (IgA and APOL1), clinical trials on arterial hypertension, urinary lithiasis, and other areas of renal physiology, including glomerular filtration rate estimation.

Toward Equitable Kidney Function Estimation in Critical Care Practice: Guidance From the Society of Critical Care Medicine's Diversity, Equity, and Inclusion in Renal Clinical Practice Task Force.

Accurate glomerular filtration rate (GFR) assessment is essential in critically ill patients. GFR is often estimated using creatinine-based equations, which require surrogates for muscle mass such as age and sex. Race has also been included in GFR equations, based on the assumption that Black individuals have genetically determined higher muscle mass. However, race-based GFR estimation has been questioned with the recognition that race is a poor surrogate for genetic ancestry, and racial health disparities are driven largely by socioeconomic factors. The American Society of Nephrology and the National Kidney Foundation (ASN/NKF) recommend widespread adoption of new "race-free" creatinine equations, and increased use of cystatin C as a race-agnostic GFR biomarker. Literature review and expert consensus. English language publications evaluating GFR assessment and racial disparities. We provide an overview of the ASN/NKF recommendations. We then apply an Implementation science methodology to identify facilitators and barriers to implementation of the ASN/NKF recommendations into critical care settings and identify evidence-based implementation strategies. Last, we highlight research priorities for advancing GFR estimation in critically ill patients. Implementation of the new creatinine-based GFR equation is facilitated by low cost and relative ease of incorporation into electronic health records. The key barrier to implementation is a lack of direct evidence in critically ill patients. Additional barriers to implementing cystatin C-based GFR estimation include higher cost and lack of test availability in most laboratories. Further, cystatin C concentrations are influenced by inflammation, which complicates interpretation. The lack of direct evidence in critically ill patients is a key barrier to broad implementation of newly developed "race-free" GFR equations. Additional research evaluating GFR equations in critically ill patients and novel approaches to dynamic kidney function estimation is required to advance equitable GFR assessment in this vulnerable population.

Refining GFR estimation: a quest for the unobservable truth?

Assessing glomerular filtration rate (GFR), which is central to evaluating kidney health, remains challenging. Measured GFR is not widely available and lacks standardization. Estimated GFR can be highly inaccurate for some patients and has limited applicability to many patient populations, such as those who are acutely ill. Recent metabolomic advances show promise for identifying new filtration markers that might enhance GFR estimation. Improving GFR assessment will require refinement in both GFR measurement and estimation methods.

Alternative creatinine-based GFR estimates in United States populations—similar performance, same gaps—is it time to move on?

This study evaluated performance of the European Kidney Function Consortium (EKFC) equation in a US cohort, comparing population-specific (EKFCPS) with race-free (EKFCRF) Q values (median normal creatinine). Both EKFCPS and EKFCRF equations showed less bias than the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 equation. The percentage of estimated glomerular filtration rate (GFR) within 30% of measured GFR was similar for CKD-EPI 2021 (79.2% [range, 78.5%-79.9%]) and EKFCRF (80.1% [range, 79.4%-80.7%]) equations but improved with the EKFCPS equation (81.1% [range, 80.5%-81.8%]), confirming utility of the EKFC equation in US populations.

New race-free creatinine- and cystatin C-based equations for the estimation of glomerular filtration rate and association with cardiovascular mortality in the AtheroGene study

Renal function is associated with cardiovascular outcomes and mortality. Among equations used to eGFR, CKD–EPI equations show more accurate association with cardiovascular risk and mortality than MDRD. Recently, new CKD–EPI equations were proposed which do not include race and would be considered sufficiently accurate to estimate eGFR in clinical practice. It is unknown if these new race-free equations are comparably well associated with cardiovascular outcomes in high-risk individuals. The analysis was performed in the AtheroGene Study cohort including patients at high cardiovascular risk. eGFR was determined using the established as well as the recently developed formulas which are calculated without the otherwise existing coefficient for black race. The outcome was cardiovascular death. Analyses included Cox-proportional hazard regression and area-under-the-curve calculation. The analysis included 2089 patients followed up for a median of 3.8 years with a maximum of 6.9 years, corresponding to an overall period of 7701 patient-years. Cardiovascular death occurred in 93 (4.45%), corresponding to an annualized rate of 1.2/100 person-years. In all Cox regression analyses, the estimated adjusted GFR was an independent predictor of cardiovascular death. The equations which included cystatin C showed higher C-index compared to those which did not include cystatin C (0.75–0.76 vs. 0.71, respectively). The equations for the estimation of eGFR which include cystatin C are better associated with cardiovascular death compared to the race-free equations which include only creatinine. This finding adds on the related literature which supports the elimination of race in GFR-estimating equations, and promotion of the use of cystatin C.

Evaluation of risk stratification for acute kidney injury: a comparative analysis of EKFC, 2009 and 2021 CKD-EPI glomerular filtration estimating equations

BackgroundThe adoption of the 2021 CKD-EPIcr equation for glomerular filtration rate (GFR) estimation provided a race-free eGFR calculation. However, the discriminative performance for AKI risk has been rarely validated. We aimed to evaluate the differences in acute kidney injury (AKI) prediction or reclassification power according to the three eGFR equations.MethodsWe performed a retrospective observational study within a tertiary hospital from 2011 to 2021. Acute kidney injury was defined according to KDIGO serum creatinine criteria. Glomerular filtration rate estimates were calculated by three GFR estimating equations: 2009 and 2021 CKD-EPIcr, and EKFC. In three equations, AKI prediction performance was evaluated with area under receiver operator curves (AUROC) and reclassification power was evaluated with net reclassification improvement analysis.ResultsA total of 187,139 individuals, including 27,447 (14.7%) AKI and 159,692 (85.3%) controls, were enrolled. In the multivariable regression prediction model, the 2009 CKD-EPIcr model (continuous eGFR model 2, 0.7583 [0.755–0.7617]) showed superior performance in AKI prediction to the 2021 CKD-EPIcr (0.7564 [0.7531–0.7597], < 0.001) or EKFC model in AUROC (0.7577 [0.7543–0.761], < 0.001). Moreover, in reclassification of AKI, the 2021 CKD-EPIcr and EKFC models showed a worse classification performance than the 2009 CKD-EPIcr model. (− 7.24 [− 8.21–− 6.21], − 2.38 [− 2.72–− 1.97]).ConclusionRegarding AKI risk stratification, the 2009 CKD-EPIcr equation showed better discriminative performance compared to the 2021 CKD-EPIcr equation in the study population.Graphical abstract

Effect of Intravitreal Anti-Endothelial Growth Factor Agents on Renal Function in Patients With Diabetes Mellitus

BackgroundIntravitreal administration of vascular endothelial growth factor inhibitors (anti-VEGF) is the treatment of choice in retinal pathology associated with type 2 diabetes mellitus (DM2). We aimed to analyze the effect on renal function in patients with DM2 after intravitreal anti-VEGF administration. MethodsSingle-center retrospective and observational study of patients with DM2 with and without chronic kidney disease (CKD). We analyzed the evolution of renal function after anti-VEGF onset, compared with a control group. ResultsWe included 45 patients (55.6% male) who received anti-VEGF therapy. Mean age was 74.4±11.5 (50-91) years. These were compared with 45 patients with similar characteristics. After 12-months, 76.3% had CKD with a mean reduction in estimate glomerular filtration rate (eGFR) of 19.4%. Nine patients (20%) had a >25% reduction in eGFR, and three patients (6.7%) had a >50% reduction in GFR. At 24-months, 80% of patients had CKD with a mean eGFR drop of 28%. The mean eGRF slope of patients who had received anti-VEGF treatment was 10 ml/min/year compared to 1,5 ml/min/year in the control group (p<0.05). After the first administration, five patients (17.2%) in the CKD group required renal replacement therapy during follow-up (mean time 22±12 months). Main risk factors for need of dialysis were age, presence of previous CKD, and baseline proteinuria. ConclusionIntravitreal anti-VEGF administration is a risk factor for CKD and rapid progression to end-stage kidney disease in patients with previous CKD. Knowing these drugs' implications is crucial to avoid CKD progression and opportunely limit their use in certain patients.

Performance evaluation of Chronic Kidney Disease Epidemiology Collaboration equations for estimated glomerular filtration rate compared to inulin clearance in Koreans.

A race-free glomerular filtration rate (GFR) estimation equation has recently been developed. However, the performance of the new Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations needs to be evaluated in Asian populations. We performed a cross-sectional study at a single center in South Korea. The measured GFR (mGFR) was determined based on systemic inulin clearance. The GFR was estimated using the five CKD-EPI equations: 2009 CKD-EPIcr, 2012 CKD-EPIcr-cys, 2012 CKD-EPIcys, 2021 CKD-EPIcr, and 2021 CKD-EPIcr-cys. The performances of five estimated GFR (eGFR) equations were assessed by bias, precision, and accuracy (percentage of estimates within 30% of mGFR). The median mGFR and interquartile range (IQR) was 53.5 (32.4-80.0) mL/min/1.73 m2. The mGFR better correlated with 2009 CKD-EPIcr (ρ = 0.628) and 2021 CKD-EPIcr-cys (ρ = 0.806) than with 2021 CKD-EPIcr (ρ = 0.623) and 2012 CKD-EPIcr-cys (ρ = 0.801). The median bias of 2009 CKD-EPIcr and 2012 CKD-EPIcr-cys were lower than those of 2021 CKD-EPI equations (2009 CKD-EPIcr, 2.24 [IQR, -8.83 to 17.39] vs. 2021 CKD-EPIcr, 5.40 [IQR, -6.04 to 20.40]; 2012 CKD-EPIcr-cys, 6.74 [IQR, -2.81 to 20.80] vs. 2021 CKD-EPIcr-cys, 10.54 [IQR, 0.30-24.37]; all in mL/min/1.73 m2). The percentage of eGFR values within 30% of mGFR was higher in 2009 CKD-EPIcr and 2012 CKD-EPIcr-cys equations than 2021 CKD-EPI equations. The CKD prevalence in 2009 CKD-EPIcr, 2021 CKD-EPIcr, 2012 CKD-EPIcr-cys, and 2021 CKD-EPIcr-cys was 54.8%, 51.0%, 47.7%, and 44.8%, respectively. Our study demonstrated better performance of the original CKD-EPIcr and CKD-EPIcr-cys equations than the 2021 new CKD-EPI equations. We do not recommend the adoption of the new CKD-EPI equations in Korea.

Association of serum syndecan-1 concentrations with albuminuria in type 2 diabetes.

Syndecan (SDC)-1 is a transmembrane heparan sulfate proteoglycan and is a major component of endothelial glycocalyx (EG). This study aimed to investigate the association of serum SDC-1 concentration as a marker of EG degradation with albuminuria in type 2 diabetes. We included 370 patients with type 2 diabetes and 219 individuals with no diabetes. The individuals with estimate glomerular filtration rate <30mL/min/1.73m2 were excluded. Serum SDC-1 concentration was higher in type 2 diabetes than in no diabetes. The presence of diabetes was independently associated with log [SDC-1] in multivariate analysis. In type 2 diabetes, serum SDC-1 concentration was correlated with log [urinary albumin-to-creatinine ratio (ACR)]. Moreover, log [SDC-1] was an independent determinant of log [ACR] after adjustment for known risk factors of albuminuria. Serum SDC-1 concentration was higher in patients with type 2 diabetes compared to individuals with no diabetes and an independent determinant of ACR. This study implicates the role of the EG degradation in albuminuria in type 2 diabetes.

Current clinical application of glomerular filtration rate assessment methods in pediatric populations

Glomerular filtration rate (GFR) is a critical indicator of renal function assessment, which exhibits age-dependency in children and may differ from adults under various disease conditions. In recent years, there has been a growing focus on GFR among scholars, with an increasing number of clinical studies dedicated to refining and optimizing GFR estimation to span all pediatric age groups. However, the methods and assessment equations for estimating GFR may vary under different disease conditions, affecting the accuracy and applicability of assessments. This article reviews the peculiarities of renal function in children, explores GFR measurement methods, and evaluates the application of various GFR assessment equations in pediatric clinical practice, providing a reference for clinical assessment of renal function in children.

Early kidney damage in diabetic adolescents with increased blood pressure and glomerular hyperfiltration.

The early impact of type 1 diabetes mellitus (DM1), increased blood pressure and glomerular hyperfiltration (GHF) on kidney damage in adolescents using two urinary markers of kidney injury - neutrophil gelatinase-associated lipocalin (uNGAL) and transferrin (uTransf) - was assessed. The study group consisted of 80 adolescents with DM1, of whom 42 were patients with increased blood pressure (IBP), and 38 were patients with normal blood pressure (NBP). Blood pressure was assessed by 24-hour ambulatory blood-pressure monitoring. All patients showed estimated glomerular-filtration rates (eGFRs) above 90 mL/min/1.73 m2. The control group consisted of 19 healthy, age and gender-matched adolescents. All diabetic children showed a significant increase in uNGAL (P<0.001). This increase was not related to blood pressure. The uNGAL was elevated in all patients with normal albuminuria, normal eGFR and NBP. The concentration of uTransf was not increased in the entire studied group and was not related to blood pressure. Children with GHF had significantly higher levels of both uTransf (P=0.010) and uNGAL (P<0.001). In patients with GHF, blood pressure was normal. Patients with IBP showed a significantly higher value for triglycerides (r=0.247; P=0.032) and a longer duration of diabetes (r=0.264; P=0.019). Diabetes is the leading risk factor for early kidney injury. However, increased blood pressure does not lead to kidney damage, at least in the early stage of DM1. The uNGAL is the early indicator of kidney injury and increases in patients with normal albuminuria, normal glomerular filtration and normal blood pressure. Glomerular hyperfiltration seems to be a marker of diabetic-kidney involvement.

Association of estimated glomerular filtration rate with prostate cancer risk in a cross-ethnic population: a Mendelian randomization study

ObjectiveTo investigate whether a causal relationship exists between the estimated glomerular filtration rate (EGFR) and the occurrence of prostate cancer in East Asian and European populations and to determine if genetic factors influence the association between the EGFR and prostate cancer risk.MethodsIn this Mendelian randomization study, the existence of a causal relationship between the EGFR and prostate cancer occurrence was assessed using five analytical techniques, including Mendelian randomization-Egger regression (MR-Egger), calculation of the weighted median estimator (WME), the maximum likelihood ratio method, the linear median weighting method and the random-effects inverse-variance weighting (IVW) method.ResultsIn the IVW model, no causal relationship was observed between the EGFR and prostate cancer in either the East Asian or European populations.ConclusionsAfter excluding confounding factors and reverse causal associations using two-sample Mendelian randomization, unbiased estimates were obtained, and there was no causal relationship between prostate cancer and the EGFR in the East Asian or European populations. Therefore, for patients with suspected prostate cancer, it is considered unnecessary to improve the detection of glomerular filtration rate, which will effectively reduce the economic burden of patients.

Comparison of different estimated glomerular filtration rates for monitoring of kidney function in oncology patients.

Tyrosine kinase inhibitors (TKIs) are associated with kidney function deterioration. A shift is ongoing towards glomerular filtration rate (GFR) equations based on other protein markers, such as cystatin C (CSTC) and β-trace protein (BTP). We evaluated various GFR equations for monitoring of kidney function in actively treated oncology patients. We monitored 110 patients receiving a TKI. Blood and urine were collected during therapy. Serum analysis included creatinine (Cr), CSTC and BTP; for consequent GFR determination. Urine was analysed for protein, albumin, immunoglobulin G, and α-1-microglobulin. A similar analysis was done in a patient subgroup receiving immune checkpoint inhibitors (ICI) as prior or subsequent line of therapy. Cr remained constant during TKI treatment (P=0.7753), whereas a significant decrease in CSTC (from week 2 onward, P<0.0001) and BTP (at weeks 2 and 4, P=0.0100) were noticed. Consequently, GFR estimations, using CSTC and/or BTP as a biochemical parameter, showed an apparent increase in GFR, whereas this was not observed for Cr-related GFR estimations. As a result, the GFR gap (ΔGFR) was significantly different from week 2 onward between Cr-based and CSTC-based GFR and between BTP-based and CSTC-based GFR. Glomerular damage was noticed with significant increase in urine protein-to-creatinine ratio, albumin-to-creatinine ratio and immunoglobulin G (all P<0.0001). No change in α-1-microglobulin was seen. ICI treatment had no effect on Cr (P=0.2262), CSTC (P=0.7341), and BTP concentrations (P=0.3592). GFR equations, in which CSTC is incorporated, fail to correctly estimate the GFR in oncology patients treated with TKIs. As TKI-treated patients show clear signs of glomerular injury, further assessment is needed on how to correctly monitor the kidney function in actively treated oncology patients.

Optimization of Kidney Health in Liver Transplant Candidates: Pretransplant Considerations and Modalities.

Patients with decompensated end-stage liver disease (ESLD) are at increased risk for mortality, and only liver transplantation (LT) offers meaningful hope for survival. These patients are at risk for kidney dysfunction through the continuum of care for ESLD including LT. We discuss the role of accurate estimation and measurement of baseline glomerular filtration rate in assessment of kidney dysfunction among those with ESLD. Optimizing kidney function is a vital goal in the management of these patients before LT. In this review, we summarize salient aspects of assessing and optimizing kidney function in this patient population. Precipitating factors and different causes of acute kidney injury are discussed, including hepatorenal syndrome. We further review treatment options for acute kidney injury including volume management. The role of vasopressor therapy, renal replacement therapy, and transjugular intrahepatic portosystemic shunting are discussed.

The Impact of Baseline Vitamin D Level in Patients Receiving Gefitinib-Directed Therapy for EGFR-Mutant Non-Small-Cell Lung Cancer.

There is contradicting evidence on vitamin D levels and cancer mortality rates. In this study, we aimed to evaluate the impact of baseline vitamin D level on the outcome in patients with estimated glomerular filtration rate (EGFR)-mutant advanced non-small-cell lung cancer (NSCLC) who received either gefitinib or gefitinib with chemotherapy (pemetrexed and carboplatin) as first-line therapy in a prospective randomized study. This was a post hoc analysis of a phase III randomized trial comparing gefitinib with gefitinib with carboplatin and pemetrexed in patients with advanced NSCLC with activating EGFR mutations in the first-line setting. As a part of regular practice, baseline vitamin D levels were measured using circulating 25(OH) levels in blood. We included 334 patients who had baseline vitamin D levels in the study and evaluated the effect of the vitamin D level on oncologic outcomes. There were 136 (40.7%) patients with a sufficient (>20 ng/mL) baseline vitamin D level, and 198 (59.3%) patients who were deficient in vitamin D (<20 ng/mL). The median progression-free survival (PFS) in patients with normal vitamin D levels was 17 months, whereas that in patients with deficient vitamin D levels was 15 months, with a hazard ratio of 1.45 (95% confidence interval [CI] = 1.03-2.06). The median overall survival (OS) in patients with normal vitamin D levels was 28.6 months, whereas that in patients with deficient vitamin D levels was 28.5 months, with a hazard ratio of 1.17 (95% CI = 0.81-1.68). On multivariate analysis, only 2 factors impacted the PFS, the baseline vitamin D level, and the treatment regimen; other factors like age, sex, disease stage, and performance status did not. Baseline vitamin D levels have a significant impact on PFS, whereas OS is not affected by the baseline vitamin D levels on patients receiving targeted therapy for EGFR-mutant lung cancer. The trial was prospectively registered with the Clinical Trial Registry of India, registration number CTRI/2016/08/007149. The date of the registration was 5 August 2016.

Measurement of Glomerular Filtration Rate in Patients Undergoing Renal Surgery for Cancer: Estimated Glomerular Filtration Rate versus Measured Glomerular Filtration Rate in the Era of Precision Medicine.

In the era of precision medicine, determining reliable renal function assessment remains a critical and debatable issue, especially in nephrology and oncology. This paper delves into the significance of accurately measured glomerular filtration rate (mGFR) in clinical practice, highlighting its essential role in guiding medical decisions and managing kidney health, particularly in the context of renal cancer (RC) patients undergoing nephrotoxic anti-cancer drugs. The limitations and advantages of traditional glomerular filtration rate (GFR) estimation methods, primarily using serum biomarkers like creatinine and cystatin C, are discussed, emphasizing their possible inadequacy in cancer patients. Specifically, newer formulae designed for GFR estimation in cancer patients may not perform at best in RC patients. The paper explores various methods for direct GFR measurement, including the gold standard inulin clearance and alternatives like iohexol plasma clearance. Despite the logistical challenges of these methods, their implementation is crucial for accurate renal function assessment. The paper concludes by emphasizing the need for continued research and innovation in GFR measurement methodologies to improve patient outcomes, particularly in populations with complex medical needs.

Evaluating the renoprotective effectiveness of sodium-glucose co-transporter 2 inhibitor therapy in patients with chronic kidney disease: A prospective study

Background/Aim. Chronic kidney disease (CKD) is a global health concern associated with increased cardio-vascular risks and premature mortality. Proteinuria is a key prognostic indicator for CKD outcome. Sodium-glucose cotransporter 2 (SGLT2) inhibitors show potential for reducing proteinuria and slowing CKD progression. The aim of the study was to determine the impact of SGLT2 inhibitor therapy on CKD patients by evaluating the changes in the level of serum creatinine (sCr), 24-hour (24h) urine protein (UP), estimated glomerular filtration rate (GFR), and blood pressure (BP). Methods. This prospective study monitored 79 patients with CKD on therapy with SGLT2 inhibitors, who were followed up for one year. Patients received an SGLT2 inhibitor (dapagliflozin) once daily (10 mg), and assessment of specific parameters was conducted at baseline, 6 months, and 1 year later during the therapy. The study evaluated the levels of sCr, 24h UP, GFR, systolic BP (BPs), diastolic BP (BPd), uric acid (UA), total cholesterol (TC), triglycerides (Tg), low-density lipoprotein (LDL) cholesterol, sodium (Na+), and potassium (K+). Results. Over the one-year follow-up, significant changes were seen in UA levels (5.36, 4.99, 4.94 mg/dL, respectively; p = 0.032), 24h UP (662.60, 574.11, 417.09 mg/dL, respectively; p = 0.028), as well as BPs (128.44, 125.64, 126.12 mmHg, respectively; p = 0.026). No significant variations were observed in GFR, BPd, sCr, TC, Tg, LDL, and K+ levels. Na+ levels displayed a notable decrease (148.21, 147.57, 146.41 mmol/L, respectively; p = 0.021). Conclusion. The study suggests a potential benefit of SGLT2 inhibitors in managing CKD.