Estimating Renal Function in Drug Development: Time to Take the Fork in the Road

Recommended Methods of Drug Dosing Adjustment for Patients With Renal Impairment

Since 2020, there have been changes in Food and Drug Administration guidance and in recommendations by national organizations with a focus on kidney diseases pertaining to the choice of equations used to estimate creatinine clearance and glomerular filtration rate in patients with renal impairment. This includes a recommendation by the National Kidney Foundation to avoid the use of the Cockcroft-Gault equation for drug dosing in patients with renal impairment. This commentary provides an overview of recent recommendations concerning kidney function assessment that have important implications for drug dosing in patients with renal impairment and provides suggestions for implementing these recommendations.

Estimated glomerular filtration rate in observational and interventional studies in chronic kidney disease

Estimated glomerular filtration rate is considered the principal measure of kidney function and, together with albuminuria, is a relevant prognostic factor for the development of end-stage kidney disease. Due to the strong association between estimated glomerular filtration rate and clinical events, such as commencement of dialysis, cardiovascular outcomes and all-cause death, estimated glomerular filtration rate is crucial for clinical decision-making in terms of scheduling follow-up and pharmacological interventions, and planning renal replacement therapies in advanced chronic kidney disease. In this review we discuss the available methods for measuring glomerular filtration rate and for estimating it through mathematical equations developed over the last few decades. We summarize the prognostic association of different percentages of estimated glomerular filtration rate decline and the main clinical outcomes, and how treatments modify estimated glomerular filtration rate decline and the risk of future endpoints. We also examine the role of pre-clinical trial slope and that of estimated glomerular filtration rate as a useful biomarker when evaluating patients for inclusion into both observational and interventional studies.

Prevalence and Risk Factors of Hyperuricemia Among Young and Middle-Aged Tibetan Men Living at Ultrahigh Altitudes: A Cross-Sectional Study

He, Ben, Jiayue Feng, Yan Shu, Lichun Yang, Zepin He, Kanxiu Liao, Hui Zhuo, and Hui Li. Prevalence and risk factors of hyperuricemia among young and middle-aged Tibetan men living at ultrahigh altitudes: a cross-sectional study. High Alt Med Biol. 25:42-48, 2024. Background: Few studies have examined the prevalence or risk factors of hyperuricemia among populations living at ultrahigh altitudes. Here we examined the prevalence of hyperuricemia and factors associated with it among young and middle-aged Tibetan men living at ultrahigh altitudes. Methods: This cross-sectional study analyzed 672 Tibetan men 18-60 years old living on the Qinghai-Tibet Plateau (mean altitude 4,014 m) within the county of Litang in the Ganzi Tibetan autonomous prefecture of Sichuan Province, China. Demographic and clinical data were collected from self-administered questionnaires, physical examinations and laboratory tests. Participants whose blood uric acid (UA) contained >420 μmol/l were classified as having hyperuricemia. Results: Of the 672 men analyzed, 332 (49.4%) had hyperuricemia. Multivariate logistic regression showed risk of hyperuricemia to correlate positively with body mass index (per 1 U increase: odds ratio [OR] 1.172, 95% confidence interval [CI] 1.1066-1.243), triglycerides (OR 1.408, 95% CI 1.084-1.828), red blood cell count (OR 1.376, 95% CI 1.009-1.875), and creatinine level (per 1 U increase: OR 1.051, 95% CI 1.033-1.070). Conversely, risk of hyperuricemia correlated negatively with the presence of diabetes mellitus (OR 0.412, 95% CI 0.175-0.968). Subgroup analyses showed that prevalence of hyperuricemia was significantly higher among those with polycythemia than among those without it, and that UA levels correlated positively with hematocrit and hemoglobin levels. Conclusions: Hyperuricemia is an important public health problem among Tibetan men living at ultrahigh altitudes in Ganzi autonomous prefecture. The region urgently requires appropriate prevention and management efforts.

Medication Management in the Critically Ill Patient with Acute Kidney Injury

ABSTRACT

AKI occurs frequently in critically ill patients. Patients with AKI, including those who require KRT, experience multiple pharmacokinetic and pharmacodynamic perturbations that dynamically influence medication effectiveness and safety. Patients with AKI may experience both subtherapeutic drug concentrations, which lead to ineffective therapy, and supratherapeutic drug concentrations, which increase the risk for toxicity. In critically ill patients with AKI not requiring KRT, conventional GFR estimation equations, especially those based on serum creatinine, have several limitations that can limit the accuracy when used for medication dosing. Alternative methods to estimate kidney function may be informative, including use of measured urinary creatinine clearance, kinetic eGFR, and equations that integrate novel kidney biomarkers. For critically ill patients with AKI requiring KRT, physicochemical properties of the drug, the KRT prescription and circuit configuration, and patient-specific factors each contribute to medication clearance. Evidence-based guidance for medication dosing during AKI requiring KRT is often limited. A working knowledge of the basic tenets of drug elimination during KRT can provide a framework for how to approach decision making when the literature is lacking. Iterative re-evaluation of a patient's progress toward therapeutic goals with a medication must occur over the arc of critical illness, including and especially in the setting of dynamic kidney function.

Estimated glomerular filtration rate with and without race for drug dosing: Cystatin C vs. serum creatinine

The goal of this study was to use a model kidney function clearance-dependent drug (vancomycin) to understand the gain or loss of precision in dosing with use of serum creatinine (S_cr ), serum cystatin C (S_cys ) and race and nonrace-based equations of the estimated glomerular filtration rate (eGFR). In this study of hospitalized patients, we compared S_cr , S_cys and their combination to estimate kidney function and vancomycin clearance. The nonrace-based S_cys eGFR model outperformed other clearance models and improved the probability of target attainment by 15%. When S_cys is not available, we show that the new 2021 CKD-EPI eGFR_cr equation (no race factor) performs as well as the current conventional approach. This improvement in model performance does not negate the need for individualized dosing but exemplifies the need to remove race as a factor of kidney-function dose adjustment.

Removing race and body surface area indexation for estimated kidney function based drug dosing: Aminoglycosides as justification of these principles

STUDY OBJECTIVE

The use of race in medicine can contribute to health inequity. Updated equations for estimated glomerular filtration rate (eGFR) without race have been published. Likewise, de-indexation of eGFR to body surface area (BSA) has been recommended by regulatory guidance for drug dosing in renal impairment. Clinical data justifying these recommendations for drug dosing are sparse. We examined the gain or loss of precision in drug dosing with estimated creatinine clearance (eCLcr) and eGFR using serum creatinine (eGFRcr) with and without race and BSA indexation by evaluating the population pharmacokinetics of the aminoglycosides as a classic drug class to probe kidney function.

DESIGN

Medical records from adult patients treated with gentamicin or tobramycin over a 13-year period were queried. Population pharmacokinetic analyses were performed using a 1-compartment base structural model. Models compared body size descriptors as covariates of the volume of distribution (V). Estimated creatinine clearance and eGFRcr using multiple contemporary equations with and without BSA indexation were tested as covariates of clearance (CL).

MAIN RESULTS

The final data set included 2968 patients treated with either gentamicin (20.2%) or tobramycin (79.8%). Patients self-identified as Caucasian (82%), African-American (10%), or other. The median [5th, 95th percentile] weight and BSA were 80.5 [49.4, 136] kg and 1.94 [1.48, 2.56] m² , respectively. Models of eCLcr and eGFRcr without indexation to BSA had a better model fit than eGFRcr indexed to BSA for aminoglycoside CL. The 2021 Chronic Kidney Disease Epidemiology collaboration (CKD-EPI) eGFRcr equation (no race, no BSA indexation) provided a comparable model fit to the 2009 CKD-EPI eGFRcr equation (with race, no BSA indexation) for aminoglycoside CL.

CONCLUSIONS

Race is not a relevant covariate of aminoglycoside CL. The 2021 CKD-EPI eGFR equation without race and BSA indexation is a better method for gentamicin and tobramycin CL estimation. Confirmation of these results for other drugs can support the harmonization of dosing by kidney function.

Nomogram model for predicting early onset of chronic kidney disease using color Doppler region of interest technique

PURPOSE

The risk factors of chronic kidney disease were analyzed by using the region of interest quantitative technology of color Doppler combined with QLab software, and a Nomogram was established to conduct an individualized assessment of patients with chronic kidney disease.

METHODS

A total of 500 patients with chronic kidney disease diagnosed in our hospital from June 2019 to March 2021 were selected as the chronic kidney disease group, and 300 healthy patients during the same period were selected as the control group. Univariate analysis was performed on the test indexes and the vascularity index, flow index, and vascularization flow index measured by the color doppler region of interest quantitative technique. The above meaningful indicators were included in the Logistics regression analysis to obtain the independent risk factors of early chronic kidney disease. The independent risk factors were imported into R software to draw a Nomogram model for predicting early chronic kidney disease and evaluate the model.

RESULTS

Single factor analysis results suggest age, hypertension, diabetes, hyperlipidemia, disease of heart head blood-vessel, body mass index, vascularity index, flow index, and vascularization flow index, fasting blood sugar, triglyceride, total cholesterol, urea nitrogen, creatinine, uric acid, glomerular filtration rate differences statistically significant (P < 0.05). Logistics regression analysis showed that hypertension, diabetes, flow index, and vascularization flow index, urea nitrogen, and albumin were independent risk factors for the early occurrence of chronic kidney disease. The C-index of this Nomogram using independent risk factors is 0.896 (95%CI 0.862-0.930), which indicates that the Nomogram has good discriminant power. The receiver operating curve of the histograph was area under the curve (AUC) 0.884 (95%CI 0.860-0.908). The receiver operator characteristic curve (ROC) of urea nitrogen, albumin, flow index, and vascularization flow index were evaluated. The results indicated that the best cutoff value of urea nitrogen was 5.9 mmol/L, flow index was 14.67, vascularization flow index was 4.6, and albumin was 40.26 g/L.

CONCLUSION

In the prediction of chronic kidney disease I-II stage, the quantitative technique of color Doppler region of interest has certain diagnostic value. The model established in this study has good discriminative power and can be applied to clinical practice, giving certain indicative significance.

Comparison of Race and Non-Race Based Equations for Kidney Function Estimation in Critically Ill Thai Patients for Vancomycin Dosing

Empiric antibiotic dosing frequently relies on an estimate of kidney function based on age, serum creatinine (SCr), sex, and race (on occasion). New non-Race based estimated glomerular filtration rate (eGFR) equations have been published but their role to support dosing is not known. Here, we report on a population pharmacokinetic model of vancomycin that serves as a useful probe substrate of eGFR in critically ill Thai patients. Data were obtained from medical records during a 10-year period. A nonlinear mixed-effects modeling approach was conducted to estimate vancomycin parameters. Data from 208 critically ill patients (58.2% male and 36.0% septic shock) with 398 vancomycin concentrations were collected. Twenty-three covariates including 12 kidney function estimates were tested and ranked based on the model performance. The median [min, max] age, weight, and SCr was 69 [18, 97] years, 60.0 [27, 120] kg, and 1.53 [0.18, 7.15] mg/dL. The best base model was a one-compartment linear with zero-order input and proportional error model. A Thai specific eGFR equation not indexed to body surface area (BSA) model best predicted vancomycin clearance (CL). The typical value for volume of distribution and CL was 67.5 L and 1.22 L/h, respectively. A loading dose of 2000 mg followed by maintenance dose regimens based on eGFR is suggested. The Thai-GFR not indexed to BSA model best predicts vancomycin CL and dosing in the critically ill Thai population. A 5-10% absolute gain in the vancomycin probability of target attainment is expected with the use of this population specific GFR equation. This article is protected by copyright. All rights reserved.

Translation of Pharmacodynamic Biomarkers of Antibiotic Efficacy in Specific Populations to Optimize Doses

Antibiotic efficacy determination in clinical trials often relies on non-inferiority designs because they afford smaller study sample sizes. These efficacy studies tend to exclude patients within specific populations or include too few patients to discern potential differences in their clinical outcomes. As a result, dosing guidance in patients with abnormal liver and kidney function, age across the lifespan, and other specific populations relies on drug exposure-matching. The underlying assumption for exposure-matching is that the disease course and the response to the antibiotic are similar in patients with and without the specific condition. While this may not be the case, clinical efficacy studies are underpowered to ensure this is true. The current paper provides an integrative review of the current approach to dose selection in specific populations. We review existing clinical trial endpoints that could be measured on a more continuous rather than a discrete scale to better inform exposure-response relationships. The inclusion of newer systemic biomarkers of efficacy can help overcome the current limitations. We use a modeling and simulation exercise to illustrate how an efficacy biomarker can inform dose selection better. Studies that inform response-matching rather than exposure-matching only are needed to improve dose selection in specific populations.

Design and conduct considerations for studies in patients with impaired renal function

An impaired renal function, including acute and chronic kidney disease and end‐stage renal disease, can be the result of aging, certain disease conditions, the use of some medications, or as a result of smoking. In patients with renal impairment (RI), the pharmacokinetics (PKs) of drugs or drug metabolites may change and result in increased safety risks or decreased efficacy. In order to make specific dose recommendations in the label of drugs for patients with RI, a clinical trial may have to be conducted or, when not feasible, modeling and simulations approaches, such as population PK modeling or physiologically‐based PK modelling may be applied. This tutorial aims to provide an overview of the global regulatory landscape and a practical guidance for successfully designing and conducting clinical RI trials or, alternatively, on applying modeling and simulation tools to come to a dose recommendation for patients with RI in the most efficient manner.

Deviant Dosing: A Post hoc Analysis of Pharmacist Characteristics Related to Renal Dosing Decisions

BACKGROUND

A recent study demonstrated that pharmacists presented with multiple estimating equations deviated from recommended dosing guidance more often than pharmacists who were presented with a single estimate on clinical vignettes.

OBJECTIVES

To identify characteristics associated with an increased tendency to deviate from approved recommendations.

METHODS

Participant data were split into 2 cohorts: pharmacists who chose a dose that was inconsistent with dosing recommendations on at least 1 of the 4 vignettes and pharmacists who did not deviate on a single case. Bivariate analysis of demographic- and practice-related variables were conducted between groups using the χ², Mann-Whitney U, or Student t-test for nominal, ordinal, and continuous variables, respectively. Statistically different covariates between groups (P < 0.05) were assessed using multivariable linear regression.

RESULTS

Survey data from 154 inpatient pharmacists, 71 of whom deviated on at least 1 clinical vignette, were analyzed. On univariate analysis, deviator pharmacists were more likely to have completed postgraduate residency training (68% vs 41%; P < 0.05) and board certification (39% vs 20%; P < 0.05). Deviator pharmacists were also more likely to have been presented with multiple renal estimates as opposed to a single estimate and had differing renal dosing practices at baseline (P < 0.05). Following multivariable regression, residency training, mismatched baseline renal practices, and multiple renal estimates remained independent predictors (P < 0.05) of dosing deviation.

CONCLUSION AND RELEVANCE

Higher clinical training, practice variation, and multiple renal estimates may affect renal dosing practices. Prospective, statistically powered studies are needed to verify these hypotheses.

Antimicrobial Dosing in Specific Populations and Novel Clinical Methodologies: Kidney Function

Kidney function is a common parameter used to define antimicrobial drug dosage and frequency of administration. Several methods exist to measure kidney function but for pragmatic reasons rely on estimated kidney function equations based on the endogenous biomarker serum creatinine and common clinical variables. Current regulatory guidance on the design of studies in patients with abnormal kidney function in the United States also recommend consideration of estimated kidney function for this reason. Over the past few decades, alternate endogenous biomarkers, administration of exogenous biomarkers for noninvasive measurement, use of probe substrates to characterize individual kidney drug clearance pathways, modifications to conventional equations to account for time-varying clearance, and improved clinical trial modeling and simulation to factor in these uncertainties have occurred. Furthermore, major changes to kidney replacement therapy delivery in the outpatient, inpatient, and at-home setting are occurring. Antimicrobial drug dose adjustment in this diverse population is complex and in a state of flux due to technical innovations. Over-reliance on kidney function estimates to guide drug dosing in patients with infectious diseases can bias underdosing especially among the acutely ill. A holistic approach to drug dose adjustment in patients with abnormal kidney function is necessary to optimize clinical outcomes.

Study on the Risk Factors for Hyperuricaemia and Related Vascular Complications in Patients with Type 2 Diabetes Mellitus

Purpose

The study aimed to identify diseases that exhibit significant differences between hyperuricaemia (HUA) and non-hyperuricaemia (NHUA) groups and analyse the risk factors for HUA based on the related diseases in type 2 diabetes mellitus (T2DM).

Methods

A total of 3264 T2DM patients were investigated from 2013 to 2017 in the Jinyang and Sanlin communities by obtaining basic data from the electronic medical record system (EMRS). From September 2018 to July 2019, 3000 patients (264 patients were missing during follow-up) were investigated with questionnaires, physical examinations and biochemical index tests. After removing missing values, 2899 patients were divided into HUA and NHUA groups. The chi-square test was used to identify diseases with differences. Using Lasso analysis and logistic regression analysis, risk factors for HUA based on the related diseases were obtained. The C-index, receiver operating characteristic (ROC) curve and calibration plot were used to validate the discrimination and accuracy of the factors.

Results

The chi-square test showed that there were significant differences in coronary heart disease (CHD) and diabetic nephropathy (DN) between the HUA group and the NHUA group. Through Lasso regression, glycosylated haemoglobin A1c (HbA1c), triglyceride (TG), blood urea nitrogen (BUN) and serum creatinine (SCR) were screened in the CHD group. Body mass index (BMI), HbA1c, total cholesterol (TC), TG, BUN, SCR and urine microalbumin (UMA) were screened in the DN group. The P-value of all the variables was less than 0.05. Through the C-index, calibration, and ROC curve analyses, these risk factors had medium accuracy.

Conclusion

HUA was significantly related to CHD and DN. The level of UA was correlated with HbA1c, TG, BUN, and SCR based on CHD. The level of UA was associated with BMI, HbA1c, TC, TG, BUN, SCR, and UMA based on DN.

Using l-Carnitine as a Pharmacologic Probe of the Interpatient and Metabolic Variability of Sepsis

OBJECTIVE

The objective of this review is to discuss the therapeutic use and differential treatment response to Levo-carnitine (l-carnitine) treatment in septic shock, and to demonstrate common lessons learned that are important to the advancement of precision medicine approaches to sepsis. We propose that significant interpatient variability in the metabolic response to l-carnitine and clinical outcomes can be used to elucidate the mechanistic underpinnings that contribute to sepsis heterogeneity.

METHODS

A narrative review was conducted that focused on explaining interpatient variability in l-carnitine treatment response. Relevant biological and patient-level characteristics considered include genetic, metabolic, and morphomic phenotypes; potential drug interactions; and pharmacokinetics (PKs).

MAIN RESULTS

Despite promising results in a phase I study, a recent phase II clinical trial of l-carnitine treatment in septic shock showed a nonsignificant reduction in mortality. However, l-carnitine treatment induces significant interpatient variability in l-carnitine and acylcarnitine concentrations over time. In particular, administration of l-carnitine induces a broad, dynamic range of serum concentrations and measured peak concentrations are associated with mortality. Applied systems pharmacology may explain variability in drug responsiveness by using patient characteristics to identify pretreatment phenotypes most likely to derive benefit from l-carnitine. Moreover, provocation of sepsis metabolism with l-carnitine offers a unique opportunity to identify metabolic response signatures associated with patient outcomes. These approaches can unmask latent metabolic pathways deranged in the sepsis syndrome and offer insight into the pathophysiology, progression, and heterogeneity of the disease.

CONCLUSIONS

The compiled evidence suggests there are several potential explanations for the variability in carnitine concentrations and clinical response to l-carnitine in septic shock. These serve as important confounders that should be considered in interpretation of l-carnitine clinical studies and broadly holds lessons for future clinical trial design in sepsis. Consideration of these factors is needed if precision medicine in sepsis is to be achieved.

The Impact of Multiple Renal Estimates on Pharmacist Dosing Recommendations: A Randomized Trial

Background:

Numerous equations are used for estimation of renal function, and many electronic medical records report multiple clearance estimates to assist with drug dosing. It is unknown whether the presence of multiple clearance estimates affects clinical decision-making.

Objective:

To determine whether the presence of multiple renal clearance estimates affects pharmacist drug dosing decisions.

Methods:

A randomized trial in the form of an electronic survey including 4 clinical vignettes was delivered to hospital pharmacists. Vignettes consisted of a patient presenting with an acute pulmonary embolism requiring enoxaparin therapy. Pharmacists were randomized to receive a single estimate of renal function or multiple estimates for all vignettes. The primary outcome was deviation from approved recommendations on at least 1 vignette. The χ2 test was used to detect differences in deviation rates between groups. Logistic regression was performed to adjust for the effects of potentially confounding variables.

Results:

A total of 154 studies were completed (73 in the multiple-estimate group and 81 in the single-estimate group). Pharmacists presented with multiple renal estimates were significantly more likely to deviate from recommended dosing regimens than pharmacists presented with a single estimate (54.7% vs 38.2%; P = 0.04). The results were driven primarily by the 2 vignettes that included discordance among Cockcroft-Gault equation creatinine clearance estimates. Logistic regression identified multiple estimates as the only independent predictor of deviation ( P = 0.04).

Conclusion and Relevance:

Pharmacists provided with a single renal clearance estimate were more likely to adhere to approved dosing recommendations than pharmacists provided with multiple estimates.

Clearance Confusion: An Exploratory Analysis of Inpatient Dosing Discordances Between Renal Estimating Equations

Background:

Numerous equations exist for estimating renal clearance for drug dosing, and discordance rates may be as high as 40% in certain populations. However, the populations and types of equations used in these studies may not be generalizable to broader pharmacy practice.

Objectives:

To determine the dosing discordance rate between Cockcroft-Gault (C-G), Chronic Kidney Disease Epidemiology (CKD-EPI), and Modification of Diet in Renal Disease (MDRD) equations in a community hospital population.

Methods:

This was a cross-sectional analysis of inpatients who had documented renal function assessment over a 6-month period. Renal estimation was calculated using 5 equations (MDRD, CKD-EPI, and 3 C-G variants). Differences between equations were assessed using mean bias, dosing discordance, and agreement (κ statistic). Patients with acute kidney injury and those requiring renal replacement therapy were excluded.

Results:

A total of 466 patients were eligible for inclusion. Dosing discordance was evident between C-G variants and both MDRD and CKD-EPI equations in greater than 20% of patients. Agreement was highest between MDRD and CKD-EPI (κ = 0.93) and lowest between MDRD and C-G calculated using ideal body weight (κ = 0.33). The majority of discordant instances led to higher dosing recommendations when using MDRD and CKD-EPI equations compared with C-G variants. Dosing discordance exceeded 18% between the different C-G variants, with the highest discordance (36%) observed between total body weight and ideal body weight variants.

Conclusion and Relevance:

Dosing discordance between renal estimating equations is widespread. Practitioners and institutions should be aware of these differences when dosing medications and implementing renal dosing policies.

Sex-specific differences in the prevalence of and risk factors for hyperuricemia among a low-income population in China: a cross-sectional study

Objectives: China has already entered the aging society, and its aging population is the largest worldwide. Accordingly, several aging-related conditions including hyperuricemia are becoming a public health concern owing to their increasing prevalence in rural areas. However, the sex-specific differences in the risk factors for hyperuricemia among the middle-aged and elderly in rural North China are unclear. Thus, this study aimed to evaluate sex-specific differences in the prevalence of and risk factors for hyperuricemia in low-income adults in rural North China. Methods: This population-based cross-sectional study recruited participants aged ≥50 years from the Tianjin Brain Study between April and August 2019. After excluding those who had cancer, severe psychiatric disturbances, hepatic failure, and serious renal disease (i.e., an estimated glomerular filtration rate (eGFR) of <30 mL/min/1.73 m²), 3119 (1392 men and 1727 women) eligible participants were included. Basic information and blood samples were collected, and data were analyzed using logistic regression models. Results: Hyperuricemia was prevalent in 14.4% (men, 14.2%; women, 14.5%)of the participants, and the prevalence significantly increased with increasing age in both sexes (male, P= 0.034; female, P< 0.001). In multivariate analysis, obesity, metabolic syndrome, and high levels of total cholesterol, 2 h plasma glucose, and blood urea nitrogen were risk factors for hyperuricemia in both men and women. Physical activity was a risk factor in men, while a high white blood cell count was a risk factor in women. A high eGFR was a protective factor in both sexes. Conclusions: Hyperuricemia was highly prevalent in low-income adults in Tianjin, with men and women showing differences in risk profiles and comorbidities. Early management of hyperuricemia according to sex-specific risk factors should be considered in primary care to reduce the prevalence and burden of hyperuricemia in rural China.

Evolution of Equations for Estimating Renal Function and Their Application to the Dosing of New Antimicrobials

Objective: To address the background and rationale for the recent introduction of the Modification of Diet in Renal Disease (MDRD) equation for renal dose adjustment of antimicrobials and to provide recommendations for pharmacists dosing new antimicrobial agents. Data Sources: Comprehensive MEDLINE and EMBASE literature searches (from August 2018 to October 2019) were performed. Search terms included creatinine clearance, Cockcroft-Gault, MDRD, and glomerular filtration rate and a subsequent search included the preceding terms AND antimicrobials OR antibiotics. Study Selection and Data Extraction: Available English-language studies on the derivation and/or use of the Cockcroft-Gault (CG) and MDRD study equation were evaluated as well as those that specifically discussed their use for dosing antimicrobial agents. Data Synthesis: The US Food and Drug Administration (FDA) approval of delafloxacin and meropenem-vaborbactam in 2017 ushered in a new era in renal dosing of antibiotics, in that both agents are recommended to be dosed by the MDRD equation. Studies demonstrate that the CG and MDRD equations can result in discrepant dosing recommendations. Relevance to Patient Care and Clinical Practice: The renal estimation equation recommended in a new antibiotic label should dictate the dosing of that medication. It is noteworthy that these equations are not interchangeable. Conclusion: Recently approved antimicrobials utilizing the MDRD equation for renal dose adjustment will be interspersed with old and new antimicrobials utilizing the CG equation because of lack of singular guidance by the FDA. This requires pharmacists to be vigilant in evaluating drug labels to determine which equation is recommended and to understand the differences, strengths, and limitations of each equation.

The Correlation between Serum Uric Acid and Renal Function in Elderly Chinese Diabetes with Normoalbuminuria

OBJECTIVE

The elder diabetic patients increases rapidly in China and often accompany with hyperuricemia. Recently evidences show that renal function has been impaired in part of diabetic patients with normoalbuminuria. Therefore, we investigated the relationship between serum uric acid (SUA) and renal function in Chinese elder diabetes with normoalbuminuria.

METHODS

The physical examination data from 1052 cases of diabetic residents with normoalbuminuria aged 70 years and over in the Jiangchuan community of Minhang District, Shanghai, from October 2011 to September 2014 was analyzed retrospectively. Each received height, body weight, waist circumference (WC), waist-to-hip ratio (WHR), blood pressure (BP), and collected samples of fasting blood and morning urine to detect blood routine, blood glucose, glycosylated hemoglobin (HbA1c), blood lipids, serum creatinine, urinary albumin, urine creatinine, and urine PH value. Correlation between SUA and renal function, an index of which is estimated using estimated glomerular filtration rate (eGFR), was analyzed.

RESULTS

The prevalence of hyperuricemia was 21.10%. Levels of WC and triglyceride (TG) increased and the levels of HbA1c, high density lipoprotein-cholesterol (HDL-C), eGFR, and urine PH decreased while the levels of SUA increased. Moreover, negative correlation of eGFR with age, WC, leukocyte, and SUA (Pearson r=0.415) was observed via Pearson correlation analysis. It indicates the strong association between SUA and eGFR. Furthermore, eGFR independently associated with SUA, age, leukocyte, hemoglobin (Hb), and fasting blood glucose (FBG) was confirmed by multiple linear stepwise regression analysis.

CONCLUSION

SUA may play an important role in the decrease of eGFR in elderly Chinese diabetic patients with normoalbuminuria.