Removing Race from eGFR calculations: Implications for Urologic Care

Impact of race-based calculations of eGFR on the management of muscle invasive bladder cancer

PURPOSE

The estimated glomerular filtration rate (eGFR) has historically been calculated with a race-coefficient multiplier (RCM); however, the RCM has been broadly criticized as inaccurate and a potential contributor to exacerbating disparities. We evaluated the impact of the RCM on eGFR and examined the 30-day post-cystectomy complications in a muscle-invasive bladder cancer cohort.

MATERIALS AND METHODS

We retrospectively analyzed patients diagnosed with MIBC who underwent cystectomy in the ACS NSQIP database from 2006 to 2020 using CPT and ICD codes. The eGFR was computed using the Modification of Diet in Renal Diseases equation which has RCM = 1.212 for black patients. Using the race data field, patients were categorized into Black and non-Black. The eGFR cut-off of 60 mL/min/1.73 m2 was chosen for patient stratification because it represents a key clinical threshold in the classification of chronic kidney disease and influences various care decisions such as chemotherapy choice. Subsequently, we examined the 30-day post-cystectomy cardiovascular and pulmonary (CV&P) complications in these patients stratified by their eGFR using descriptive statistics and a multivariable logistic regression model.

RESULTS

The application of the RCM to estimate eGFR in the Black cohort increased the mean eGFR from 57.8 to 70.0 ml/min/1.73 m2 (P = 0.001) which led to a 17.3% (45.6% vs 62.9%, P = 0.001) increase in the proportion of Black patients with eGFR≥60 ml/min/1.73 m2. The rate of CV&P complications post-cystectomy among this group of 17.3% of patients in the Black cohort was 7.6% compared to a 4.3% complication rate among a non-Black cohort matched for similar eGFR for whom RCM was not applied (P = 0.06). Black patients in this RCM-dependent category of eGFR≥60 mL/min/1.73 m2 had higher adjusted odds of developing 30-day post cystectomy CV&P complications compared to eGFR-matched non-Black patients (OR = 2.2, 95% CI = 1.13-4.31, P = 0.02).

CONCLUSION

In this study, we found that inclusion of RCM in the eGFR significantly increases the proportion of Black patients with eGFR≥60. This RCM might also be associated with higher post-cystectomy CV&P complications; therefore, future studies are needed to evaluate the implications of race-based algorithms on outcomes.

Literacy and Language Barriers to Overcome in Laboratory Medicine

In the context of laboratory medicine, the authors describe 3 barriers to health communication: access, health communication, and language responsiveness. These barriers are interconnected and present in millions of people in need of equitable access to health communication. Equitable access entails health communication written in plain language and languages other than English to address language and literacy barriers and increase trust by avoiding language discordance and the spread of infodemics. This review includes several options to implement multidisciplinary efforts that lead to measurable improvements in health literacy.

When Positive is Negative: Health Literacy Barriers to Patient Access to Clinical Laboratory Test Results

BACKGROUND

Health literacy is a multidimensional set of skills (e.g., narrative, numeracy, digital, medication) that patients need to access and understand health information timely and accurately to make evidence-based informed decisions.

CONTENT

Multiple barriers prevent patients from effectively interacting with health information. The most salient barriers are poor overall health literacy skills and linguistic proficiency in English. As patients prefer direct access to laboratory test results, especially those of routine tests, contextualization and provider-directed interpretation of results are required to foster shared decision-making to address their healthcare issues and improve health outcomes.

SUMMARY

The use of systematic approaches that account for poor health literacy skills and include culturally and linguistically appropriate planning and availability of resources is warranted at individual and population health levels (e.g., human-centered design of patient portals).

Retaining Race in Chronic Kidney Disease Diagnosis and Treatment

The best overall measure of kidney function is glomerular filtration rate (GFR) as commonly estimated from serum creatinine concentrations (eGFRcr) using formulas that correct for the higher average creatinine concentrations in Blacks. After two decades of use, these formulas have come under scrutiny for estimating GFR differently in Blacks and non-Blacks. Discussions of whether to include race (Black vs. non-Black) in the calculation of eGFRcr fail to acknowledge that the original race-based eGFRcr provided the same CKD treatment recommendations for Blacks and non-Blacks based on directly (exogenously) measured GFR. Nevertheless, the National Kidney Foundation and the American Society of Nephrology Task Force on Reassessing the Inclusion of Race in Diagnosing Kidney Disease removed race in CKD treatment guidelines and pushed for the immediate adoption of a race-free eGFRcr formula by physicians and clinical laboratories. This formula is projected to negate CKD in 5.51 million White and other non-Black adults and reclassify CKD to less severe stages in another 4.59 million non-Blacks, in order to expand treatment eligibility to 434,000 Blacks not previously diagnosed and to 584,000 Blacks previously diagnosed with less severe CKD. This review examines: 1) the validity of the arguments for removing the original race correction, and 2) the performance of the proposed replacement formula. Excluding race in the derivation of eGFRcr changed the statistical bias from +3.7 to -3.6 ml/min/1.73m2 in Blacks and from +0.5 to +3.9 in non-Blacks, i.e., promoting CKD diagnosis in Blacks at the cost of restricting diagnosis in non-Blacks. By doing so, the revised eGFRcr greatly exaggerates the purported racial disparity in CKD burden. Claims that the revised formulas identify heretofore undiagnosed CKD in Blacks are not supported when studies that used kidney failure replacement therapy and mortality are interpreted as proxies for baseline CKD. Alternatively, a race-stratified eGFRcr (i.e., separate equations for Blacks and non-Blacks) would provide the least biased eGFRcr for both Blacks and non-Blacks and the best medical treatment for all patients.

Race-free estimated glomerular filtration rate equation in kidney transplant recipients: development and validation study

OBJECTIVE

To compare the performance of a newly developed race-free kidney recipient specific glomerular filtration rate (GFR) equation with the three current main equations for measuring GFR in kidney transplant recipients.

DESIGN

Development and validation study SETTING: 17 cohorts in Europe, the United States, and Australia (14 transplant centres, three clinical trials).

PARTICIPANTS

15 489 adults (3622 in development cohort (Necker, Saint Louis, and Toulouse hospitals, France), 11 867 in multiple external validation cohorts) who received kidney transplants between 1 January 2000 and 1 January 2021.

MAIN OUTCOME MEASURE

The main outcome measure was GFR, measured according to local practice. Performance of the GFR equations was assessed using P30 (proportion of estimated GFR (eGFR) within 30% of measured GFR (mGFR)) and correct classification (agreement between eGFR and mGFR according to GFR stages). The race-free equation, based on creatinine level, age, and sex, was developed using additive and multiplicative linear regressions, and its performance was compared with the three current main GFR equations: Modification of Diet in Renal Disease (MDRD) equation, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2009 equation, and race-free CKD-EPI 2021 equation.

RESULTS

The study included 15 489 participants, with 50 464 mGFR and eGFR values. The mean GFR was 53.18 mL/min/1.73m2 (SD 17.23) in the development cohort and 55.90 mL/min/1.73m2 (19.69) in the external validation cohorts. Among the current GFR equations, the race-free CKD-EPI 2021 equation showed the lowest performance compared with the MDRD and CKD-EPI 2009 equations. When race was included in the kidney recipient specific GFR equation, performance did not increase. The race-free kidney recipient specific GFR equation showed significantly improved performance compared with the race-free CKD-EPI 2021 equation and performed well in the external validation cohorts (P30 ranging from 73.0% to 91.3%). The race-free kidney recipient specific GFR equation performed well in several subpopulations of kidney transplant recipients stratified by race (P30 73.0-91.3%), sex (72.7-91.4%), age (70.3-92.0%), body mass index (64.5-100%), donor type (58.5-92.9%), donor age (68.3-94.3%), treatment (78.5-85.2%), creatinine level (72.8-91.3%), GFR measurement method (73.0-91.3%), and timing of GFR measurement post-transplant (72.9-95.5%). An online application was developed that estimates GFR based on recipient's creatinine level, age, and sex (https://transplant-prediction-system.shinyapps.io/eGFR_equation_KTX/).

CONCLUSION

A new race-free kidney recipient specific GFR equation was developed and validated using multiple, large, international cohorts of kidney transplant recipients. The equation showed high accuracy and outperformed the race-free CKD-EPI 2021 equation that was developed in individuals with native kidneys.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05229939.

Addressing Racism in Ethics Consultation: An Expansion of the Four-Box Method

AbstractRacism is a pervasive issue in patient care and a key social determinant of health. Clinical ethicists, like others involved in patient care, have a duty to recognize and respond to racism on both individual and systems-wide levels to improve patient care. Doing so can be challenging and, like other skills in ethics consultation, may benefit from specialized training, standardized tools and approaches, and practice. Learning from existing frameworks and tools, as well as building new ones, can help guide clinical ethicists to systematically approach racism as it affects clinical cases. Here, we propose an expansion of the commonly used four-box method to clinical ethics consultation, where racism is considered as a potential factor in each of the four boxes. We apply this method to two clinical cases to highlight ethically salient information that might be missed using the standard formulation of the four boxes but captured with the expanded version. We argue that this expansion of an existing clinical ethics consultation tool is ethically justified insofar as it (a) creates a more just approach, (b) supports individual consultants and services, and (c) facilitates communication in contexts where racism impinges on effecting good patient care.