Evaluating the Impact and Rationale of Race-Specific Estimations of Kidney Function: Estimations from U.S. NHANES, 2015-2018.

BACKGROUND: Standard equations for estimating glomerular filtration rate (eGFR) employ race multipliers, systematically inflating eGFR for Black patients. Such inflation is clinically significant because eGFR thresholds of 60, 30, and 20 ml/min/1.73m2 guide kidney disease management. Racialized adjustment of eGFR in Black Americans may thereby affect their clinical care. In this study, we analyze and extrapolate national data to assess potential impacts of the eGFR race adjustment on qualification for kidney disease diagnosis, nephrologist referral, and transplantation listing. METHODS: Using population-representative cross-sectional data from the United States National Health and Nutrition Examination Survey (NHANES) from 2015-2018, eGFR values for Black Americans were calculated using the Modification of Diet in Renal Disease (MDRD) equation with and without the 1.21 race-specific coefficient using cohort data on age, sex, race, and serum creatinine. FINDINGS: Without the MDRD eGFR race adjustment, 3.3 million (10.4%) more Black Americans would reach a diagnostic threshold for Stage 3 Chronic Kidney Disease, 300,000 (0.7%) more would qualify for beneficial nephrologist referral, and 31,000 (0.1%) more would become eligible for transplant evaluation and waitlist inclusion. INTERPRETATION: These findings suggest eGFR race coefficients may contribute to racial differences in the management of kidney. We provide recommendations for addressing this issue at institutional and individual levels. FUNDING: No external funding was received for this study.

Impact of pre-dialysis nephrology care engagement and decision-making on provider and patient action toward permanent vascular access.

BACKGROUND: While catheters are often thought the result of emergency hemodialysis (HD) initiation among patients with little or no pre-dialysis nephrology care, the role of patient level of engagement in care and modality decision-making have not been fully explored. METHODS: This is a retrospective medical record review of adults (age 18-89 years) who received care in academically affiliated private practice, public hospital, or Veterans Administration settings prior to initiating HD with a catheter between 10/1/2011 and 9/30/2012. Primary predictors were level of patient engagement in nephrology care within 6 months of HD initiation and timing of modality decision-making. Primary outcomes were provider action (referral) and any patient action (evaluation by a vascular surgeon, vein mapping or vascular surgery) toward [arteriovenous fistula or graft, (AVF/AVG)] creation. RESULTS: Among 92 incident HD patients, 66% (n = 61) initiated HD via catheter, of whom 34% (n = 21) had ideal engagement in care but 42% (n = 25) had no documented decision. Providers referred 48% (n = 29) of patients for AVF/AVG, of whom 72% (n = 21) took any action. Ideal engagement in care predicted provider action (adjusted OR 13.7 [95% CI 1.08, 175.1], p = 0.04), but no level of engagement in care predicted patient action (p > 0.3). Compared to patients with no documented decision, those with documented decisions within 3, 3-12, or more than 12 months before initiating dialysis were more likely to have provider action toward AVF/AVG (adjusted OR [95% CI]: 9.0 [1.4,55.6], p = 0.2, 37.6 [3.3423.4] p = 0.003, and 4.8 [0.8, 30.6], p = 0.1, respectively); and patient action (adjusted OR [95% CI]: 18.7 [2.3, 149.0], p = 0.006, 20.4 [2.6, 160.0], p = 0.004, and 6.2 [0.9, 44.0], p = 0.07, respectively). CONCLUSIONS: Timing of patient modality decision-making, but not level of engagement in pre-dialysis nephrology care, was predictive of patient and provider action toward AVF/AVG Interventions addressing patients' psychological preparation for dialysis are needed.

A Conceptual Framework of Palliative Care across the Continuum of Advanced Kidney Disease.

Kidney palliative care is a growing discipline within nephrology. Kidney palliative care specifically addresses the stress and burden of advanced kidney disease through the provision of expert symptom management, caregiver support, and advance care planning with the goal of optimizing quality of life for patients and families. The integration of palliative care principles is necessary to address the multidimensional impact of advanced kidney disease on patients. In particular, patients with advanced kidney disease have a high symptom burden and experience greater intensity of care at the end of life compared with other chronic serious illnesses. Currently, access to kidney palliative care is lacking, whether delivered by trained kidney care professionals or by palliative care clinicians. These barriers include a gap in training and workforce, policies limiting access to hospice and outpatient palliative care services for patients with ESKD, resistance to integrating palliative care within the nephrology community, and the misconception that palliative care is synonymous with end-of-life care. As such, addressing kidney palliative care needs on a population level will require not only access to specialized kidney palliative care initiatives, but also equipping kidney care professionals with the skills to address basic kidney palliative care needs. This article will address the role of kidney palliative care for patients with advanced kidney disease, describe models of care including primary and specialty kidney palliative care, and outline strategies to improve kidney palliative care on a provider and system level.

Characteristics and Outcomes of In-Hospital Palliative Care Consultation among Patients with Renal Disease Versus Other Serious Illnesses.

BACKGROUND AND OBJECTIVES: Despite significant morbidity and mortality associated with ESRD, these patients receive palliative care services much less often than patients with other serious illnesses, perhaps because they are perceived as having less need for such services. We compared characteristics and outcomes of hospitalized patients in the United States who had a palliative care consultation for renal disease versus other serious illnesses. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In this observational study, we used data collected by the Palliative Care Quality Network, a national palliative care quality improvement collaborative. The 23-item Palliative Care Quality Network core dataset includes demographics, processes of care, and clinical outcomes of all hospitalized patients who received a palliative care consultation between December of 2012 and March of 2016. RESULTS: The cohort included 33,183 patients, of whom 1057 (3.2%) had renal disease as the primary reason for palliative care consultation. Mean age was 71.9 (SD=16.8) or 72.8 (SD=15.2) years old for those with renal disease or other illnesses, respectively. At the time of consultation, patients with renal disease or other illnesses had similarly low mean Palliative Performance Scale scores (36.0% versus 34.9%, respectively; P=0.08) and reported similar moderate to severe anxiety (14.9% versus 15.3%, respectively; P=0.90) and nausea (5.9% versus 5.9%, respectively; P>0.99). Symptoms improved similarly after consultation regardless of diagnosis (P≥0.50), except anxiety, which improved more often among those with renal disease (92.0% versus 66.0%, respectively; P=0.002). Although change in code status was similar among patients with renal disease versus other illnesses, from over 60% full code initially to 30% full code after palliative care consultation, fewer patients with renal disease were referred to hospice than those with other illnesses (30.7% versus 37.6%, respectively; P<0.001). CONCLUSIONS: Hospitalized patients with renal disease referred for palliative care consultation had similar palliative care needs, improved symptom management, and clarification of goals of care as those with other serious illnesses.

The Kidney and Periodontal Disease (KAPD) study: A pilot randomized controlled trial testing the effect of non-surgical periodontal therapy on chronic kidney disease.

INTRODUCTION: Chronic kidney disease (CKD) remains a prevalent public health problem that disproportionately affects minorities and the poor, despite intense efforts targeting traditional risk factors. Periodontal diseases are common bacterial plaque-induced inflammatory conditions that can respond to treatment and have been implicated as a CKD risk factor. However there is limited evidence that treatment of periodontal disease slows the progression of CKD. METHODS/DESIGN: We describe the protocol of the Kidney and Periodontal Disease (KAPD) study, a 12-month un-blinded, randomized, controlled pilot trial with two intent-to-treat treatment arms: 1. immediate intensive non-surgical periodontal treatment or 2. rescue treatment with delayed intensive treatment. The goals of this pilot study are to test the feasibility of conducting a larger trial in an ethnically and racially diverse, underserved population (mostly poor and/or low literacy) with both CKD and significant periodontal disease to determine the effect of intensive periodontal treatment on renal and inflammatory biomarkers over a 12-month period. RESULTS: To date, KAPD has identified 634 potentially eligible patients who were invited to in-person screening. Of the 83 (13.1%) of potentially eligible patients who attended in-person screening, 51 (61.4%) were eligible for participation and 46 enrolled in the study. The mean age of participants is 59.2years (range 34 to 73). Twenty of the participants (43.5%) are Black and 22 (47.8%) are Hispanic. DISCUSSION: Results from the KAPD study will provide needed preliminary evidence of the effectiveness of non-surgical periodontal treatment to slow CKD progression and inform the design future clinical research trials.

The association of periodontal disease with kidney function decline: a longitudinal retrospective analysis of the MrOS dental study.

BACKGROUND: Identifying modifiable risk factors for chronic kidney disease (CKD) is essential for reducing its burden. Periodontal disease is common, modifiable and has been implicated as a novel potential CKD risk factor, but evidence of its association with kidney function decline over time is limited. METHODS: In a longitudinal retrospective cohort of 761 elderly men with preserved kidney function [estimated glomerular filtration rate > 60 mL/min/1.73 m(2) using a calibrated creatinine and cystatin C (eGFRcr-cys) equation] at baseline, we performed multivariable Poisson's regression to examine the association of severe periodontal disease with incident CKD, defined as incident eGFRcr-cys <60 mL/min/1.73 m(2) and rapid (>5% annualized) eGFRcr-cys decline. Severe periodontal disease was defined in two ways: (i) ≥5 mm proximal attachment loss in 30% of teeth examined (European Workshop in Periodontology Group C, European Workshop); and (ii) 2+ interproximal sites with attachment loss ≥6 mm and 1+ interproximal sites with probing depth ≥5 mm (Centers for Disease Control/American Academy of Periodontology, CDC/AAP). RESULTS: At baseline, the mean age was 73.4 (SD 4.8) years, the median eGFRcr-cys was 82.4 mL/min/1.73 m(2), and 35.5 and 25.4% of participants had severe periodontal disease by European Workshop and CDC/AAP criteria, respectively. After a mean follow-up of 4.9 years (SD 0.3), 56 (7.4%) participants had incident CKD. Severe periodontal disease was associated with a 2-fold greater rate of incident CKD [incidence rate ratio (IRR) 2.01 (1.21-3.44), P = 0.007] after adjusting for confounders compared with not severe periodontal disease by European Workshop criteria but did not reach statistical significance by CDC/AAP criteria [IRR 1.10 (0.63-1.91), P = 0.9]. CONCLUSIONS: Severe periodontal disease may be associated with incident clinically significant kidney function decline among a cohort of elderly men.

Potential Impact of Prescribing Metformin According to eGFR Rather Than Serum Creatinine.

OBJECTIVE: Many societies recommend using estimated glomerular filtration rate (eGFR) rather than serum creatinine (sCr) to determine metformin eligibility. We examined the potential impact of these recommendations on metformin eligibility among U.S. adults. RESEARCH DESIGN AND METHODS: Metformin eligibility was assessed among 3,902 adults with diabetes who participated in the 1999-2010 National Health and Nutrition Examination Surveys and reported routine access to health care, using conventional sCr thresholds (eligible if <1.4 mg/dL for women and <1.5 mg/dL for men) and eGFR categories: likely safe, ≥45 mL/min/1.73 m(2); contraindicated, <30 mL/min/1.73 m(2); and indeterminate, 30-44 mL/min/1.73 m(2)). Different eGFR equations were used: four-variable MDRD, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine (CKD-EPIcr), and CKD-EPI cystatin C, as well as Cockcroft-Gault (CG) to estimate creatinine clearance (CrCl). Diabetes was defined by self-report or A1C ≥6.5% (48 mmol/mol). We used logistic regression to identify populations for whom metformin was likely safe adjusted for age, race/ethnicity, and sex. Results were weighted to the U.S. adult population. RESULTS: Among adults with sCr above conventional cutoffs, MDRD eGFR ≥45 mL/min/1.73 m(2) was most common among men (adjusted odds ratio [aOR] 33.3 [95% CI 7.4-151.5] vs. women) and non-Hispanic Blacks (aOR vs. whites 14.8 [4.27-51.7]). No individuals with sCr below conventional cutoffs had an MDRD eGFR <30 mL/min/1.73 m(2). All estimating equations expanded the population of individuals for whom metformin is likely safe, ranging from 86,900 (CKD-EPIcr) to 834,800 (CG). All equations identified larger populations with eGFR 30-44 mL/min/1.73 m(2), for whom metformin safety is indeterminate, ranging from 784,700 (CKD-EPIcr) to 1,636,000 (CG). CONCLUSIONS: The use of eGFR or CrCl to determine metformin eligibility instead of sCr can expand the adult population with diabetes for whom metformin is likely safe, particularly among non-Hispanic blacks and men.

Association Between Periodontal Disease and Kidney Function Decline in African Americans: The Jackson Heart Study.

BACKGROUND: Chronic kidney disease (CKD) remains a prevalent public health problem that disproportionately affects African Americans, despite intense efforts targeting traditional risk factors. Periodontal disease, a chronic bacterial infection of the oral cavity, is both common and modifiable and has been implicated as a novel potential CKD risk factor. The authors seek to examine to what extent periodontal disease is associated with kidney function decline. METHODS: This retrospective cohort study examines 699 African American participants with preserved kidney function (defined by estimated glomerular filtration rate (eGFR) >60 mL/minute/1.73 m(2) at baseline) who underwent complete dental examinations as part of the Dental-Atherosclerosis Risk in Communities study (1996 to 1998) and subsequently enrolled in the Jackson Heart Study (2000 to 2004). Using multivariable Poisson regression, the authors examined the association of periodontal disease (severe versus non-severe) with incident CKD, defined as incident eGFR <60 mL/minute/1.73 m(2) and rapid (5% annualized) eGFR decline at follow-up among those with preserved eGFR at baseline. RESULTS: Mean (± SD) age at baseline was 65.4 (± 5.2) years, and 16.3% (n = 114) had severe periodontal disease. There were 21 cases (3.0%) of incident CKD after a mean follow-up of 4.8 (± 0.6) years. Compared with participants with non-severe periodontal disease, those with severe periodontal disease had a four-fold greater rate of incident CKD (adjusted incidence rate ratio 4.18 [95% confidence interval 1.68 to 10.39], P = 0.002). CONCLUSIONS: Severe periodontal disease is prevalent among a population at high risk for CKD and is associated with clinically significant kidney function decline. Further research is needed to determine if periodontal disease treatment alters the trajectory of renal deterioration.

A palliative approach to dialysis care: a patient-centered transition to the end of life.

As the importance of providing patient-centered palliative care for patients with advanced illnesses gains attention, standard dialysis delivery may be inconsistent with the goals of care for many patients with ESRD. Many dialysis patients with life expectancy of <1 year may desire a palliative approach to dialysis care, which focuses on aligning patient treatment with patients' informed preferences. This commentary elucidates what comprises a palliative approach to dialysis care and describes its potential and appropriate use. It also reviews the barriers to integrating such an approach into the current clinical paradigm of care and existing infrastructure and outlines system-level changes needed to accommodate such an approach.

Effect of food insecurity on chronic kidney disease in lower-income Americans.

BACKGROUND: The relation of food insecurity (inability to acquire nutritionally adequate and safe foods) and chronic kidney disease (CKD) is unknown. We examined whether food insecurity is associated with prevalent CKD among lower-income individuals in both the general US adult population and an urban population. METHODS: We conducted cross-sectional analyses of lower-income participants of the National Health and Nutrition Examination Survey (NHANES) 2003-2008 (n = 9,126) and the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study (n = 1,239). Food insecurity was defined based on questionnaires and CKD was defined by reduced estimated glomerular filtration rate or albuminuria; adjustment was performed with multivariable logistic regression. RESULTS: In NHANES, the age-adjusted prevalence of CKD was 20.3, 17.6, and 15.7% for the high, marginal, and no food insecurity groups, respectively. Analyses adjusting for sociodemographics and smoking status revealed high food insecurity to be associated with greater odds of CKD only among participants with either diabetes (OR = 1.67, 95% CI: 1.14-2.45 comparing high to no food insecurity groups) or hypertension (OR = 1.37, 95% CI: 1.03-1.82). In HANDLS, the age-adjusted CKD prevalence was 5.9 and 4.6% for those with and without food insecurity, respectively (p = 0.33). Food insecurity was associated with a trend towards greater odds of CKD (OR = 1.46, 95% CI: 0.98-2.18) with no evidence of effect modification across diabetes, hypertension, or obesity subgroups. CONCLUSION: Food insecurity may contribute to disparities in kidney disease, especially among persons with diabetes or hypertension, and is worthy of further study.

Body mass index and early kidney function decline in young adults: a longitudinal analysis of the CARDIA (Coronary Artery Risk Development in Young Adults) study.

BACKGROUND: Identifying potentially modifiable risk factors is critically important for reducing the burden of chronic kidney disease. We sought to examine the association of body mass index (BMI) with kidney function decline in a cohort of young adults with preserved glomerular filtration at baseline. STUDY DESIGN: Longitudinal cohort. SETTING & PARTICIPANTS: 2,839 black and white young adults with cystatin C-based estimated glomerular filtration rate (eGFRcys)>90mL/min/1.73m(2) taking part in the year-10 examination (in 1995-1996) of the Coronary Artery Risk Development in Young Adults (CARDIA) Study. PREDICTOR: BMI, categorized as 18.5-24.9 (reference), 25.0-29.9, 30.0-39.9, and ≥40.0kg/m(2). OUTCOMES: Trajectory of kidney function decline, rapid decline (>3% per year), and incident eGFRcys <60mL/min/1.73m(2) over 10 years of follow-up. MEASUREMENTS: GFRcys estimated from the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation for calibrated cystatin C at CARDIA years 10, 15, and 20. RESULTS: At year 10, participants had a mean age of 35.1 years, median eGFRcys of 114mL/min/1.73m(2), and 24.5% had BMI≥30.0kg/m(2). After age 30 years, average eGFRcys was progressively lower with each increment in BMI after adjustment for baseline age, race, sex, hyperlipidemia, smoking status, and physical activity. Higher BMI category was associated with successively higher odds of rapid decline (for 25.0-29.9, 30.0-39.9, and ≥40.0kg/m(2), adjusted ORs were 1.50 [95% CI, 1.21-1.87], 2.01 [95% CI, 1.57-2.87], and 2.57 [95% CI, 1.67-3.94], respectively). 18 participants (0.6%) had incident eGFRcys<60mL/min/1.73m(2). In unadjusted analysis, higher BMI category was associated with incident eGFRcys<60mL/min/1.73m(2) (for 25.0-29.9, 30.0-39.9, and ≥40.0kg/m(2), ORs were 5.17 [95% CI, 1.10-25.38], 7.44 [95% CI, 1.54-35.95], and 5.55 [95% CI, 0.50-61.81], respectively); adjusted associations were no longer significant. LIMITATIONS: Inability to describe kidney function before differences by BMI category were already evident. Absence of data for measured GFR or GFR estimated from serum creatinine level. CONCLUSIONS: Higher BMI categories are associated with greater declines in kidney function in a cohort of young adults with preserved GFR at baseline. Clinicians should vigilantly monitor overweight and obese patients for evidence of early kidney function decline.

Estimated kidney function based on serum cystatin C and risk of subsequent coronary artery calcium in young and middle-aged adults with preserved kidney function: results from the CARDIA study.

Whether kidney dysfunction is associated with coronary artery calcium (CAC) in young and middle-aged adults who have a cystatin C-derived estimated glomerular filtration rate (eGFRcys) greater than 60 mL/min/1.73 m(2) is unknown. In the Coronary Artery Risk Development in Young Adults (CARDIA) cohort (recruited in 1985 and 1986 in Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California), we examined 1) the association of eGFRcys at years 10 and 15 and detectable CAC over the subsequent 5 years and 2) the association of change in eGFRcys and subsequent CAC, comparing those with stable eGFRcys to those whose eGFRcys increased (>3% annually over 5 years), declined moderately (3%-5%), or declined rapidly (>5%). Generalized estimating equation Poisson models were used, with adjustment for age, sex, race, educational level, income, family history of coronary artery disease, diabetes, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and tobacco use. Among 3,070 participants (mean age 35.6 (standard deviation, 4.1) years and mean eGFRcys 106.7 (standard deviation, 18.5) mL/min/1.73 m(2)), 529 had detectable CAC. Baseline eGFRcys was not associated with CAC. Moderate eGFRcys decline was associated with a 33% greater relative risk of subsequent CAC (95% confidence interval: 5, 68; P = 0.02), whereas rapid decline was associated with a 51% higher relative risk (95% confidence interval: 10, 208; P = 0.01) in adjusted models. In conclusion, among young and middle-aged adults with eGFRcys greater than 60 mL/min/1.73 m(2), annual decline in eGFRcys is an independent risk factor for subsequent CAC.

Vulnerable populations and the association between periodontal and chronic kidney disease.

BACKGROUND AND OBJECTIVES: Recent studies suggest an overall association between chronic kidney disease (CKD) and periodontal disease, but it is unknown whether this association is similar across various subpopulations. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This study was a cross-sectional analysis of 2001 to 2004 National Health and Nutrition Examination Survey data. CKD was defined as a urinary albumin-to-creatinine ratio ≥30 mg/g or estimated GFR of 15 to 59 ml/min per 1.73 m(2). Adjusted odds ratios were calculated using multivariable logistic regression with U.S. population-based weighting. RESULTS: These analyses included 6199 dentate adult participants (aged 21 to 75 years) with periodontal exams. The estimated prevalences of moderate/severe periodontal disease and CKD were 5.3% and 10.6%, respectively. Periodontal disease was associated with >2-fold higher risk of CKD that was moderately attenuated after adjustment for age, gender, race/ethnicity, tobacco use, hypertension, diabetes, educational attainment, poverty index ratio, and dental care use. There were no statistically significant interactions between periodontal disease and race/ethnicity, educational attainment, or poverty status. Less-than-recommended dental care use was associated with periodontal disease and CKD and was increasingly prevalent among nonwhites, lower educational attainment, and lower poverty status. CONCLUSIONS: The association between periodontal disease and CKD is not significantly different among subgroups. However, because nonwhites, those with a lower educational level, and the poor less frequently report use of recommended dental care, the association between periodontal disease and kidney function over time may become stronger among these groups and warrants further investigation.

Acute myocardial infarction length of stay and hospital mortality are not associated with language preference.

BACKGROUND: Language barriers between patients and providers may influence the process and quality of care. OBJECTIVE: To examine the association of language preference with length of stay (LOS) and in-hospital mortality for patients admitted for acute myocardial infarction (AMI). DESIGN, SETTING, AND PARTICIPANTS: Electronic administrative hospital discharge data for all non-disabled Medicaid beneficiaries age 35 years and older admitted to all acute care California hospitals with a diagnosis of AMI between 1994 and 1998. METHODS: We used multivariate regression to explore whether observed differences in the hospital LOS and in-hospital mortality between non-English preference (NEP) and English preference (EP) individuals could be explained by individual and/or hospital level factors. We adjusted for patient level characteristics using 24 covariates from a previously validated prediction model of mortality after hospitalization for AMI. RESULTS: Of 12,609 Medicaid patients across 401 California hospitals, 2,757 (22%) had NEP. NEP was associated with a 3.9% increased LOS (95% CI 0.7, 7.1; p = 0.02) in unadjusted analysis and a 3.8% increased LOS (95% CI 0.3, 7.3; p = 0.03) after controlling for patient level characteristics. Differences in LOS were no longer significant after adjusting receipt of cardiac procedure/ surgery (2.8%; 95% CI -0.6, 6.2; p = 0.1) or after adjusting for hospital (0.9%; 95% CI -2.5, 4.3; p = 0.6). Non-English language preference was associated with lower in-hospital mortality in unadjusted analysis (odds ratio [OR] = 0.80; 95% CI 0.69, 0.94; p = 0.005), but was not significant after adjusting for patient level characteristics (adjusted OR [AOR] 0.95; 95% CI 0.78, 1.27; p = 0.6). Adjusting for receipt of cardiac procedure/ surgery (AOR 0.97; 95% CI 0.79, 1.18; p = 0.7) and hospital (AOR 0.97; 95% CI 0.78; 1.21; p = 0.8) did not alter this finding. CONCLUSIONS: Language preference is not associated with AMI mortality, and the small increase in length of stay associated with non-English preference is accounted for by hospital level factors. Our results suggest that system level differences are important to consider in studies of the effect of language barriers in the health care setting.