Controversies in timing of dialysis initiation and the role of race and demographics

Challenges for eGFR equations in the developing world

The populations in countries that have the highest number of individuals with chronic kidney disease (CKD) are the low and middle-income countries which are ethnically diverse. The regional and international data highlighting the need for continuous monitoring of renal function warrants that such countries use equations that give the best estimates of glomerular filtration rate for their settings. While chronic disease conditions such as diabetes and hypertension are the main conditions associated with CKD in adult populations and complicated urinary tract infections and congenital anomalies in the kidney and the urinary tract in the young, the management of patients with CKD at any age can be impacted by medical and non-biological factors. This communication seeks to posit issues that may be germane to consider when using the CKD-EPI 2021 equations in the adult and young adult populations. These equations, by excluding the race factor, have put the spotlight on the relevance of the cultural and economic context concerning the management of renal patents. The social determinants of health, how an individual defines their gender, the cultural acceptance of such or the lack thereof, factors influencing the choice of the test, communication, and technology among others may all affect renal care. These issues together may have a greater impact on renal patient care and outcome than racial disparity. While the racial divide may have been a driver for differential treatment in developed nations with different ethnic groups they may be less so when compared with more homogenous populations.

The Construction and Meaning of Race Within Hypertension Guidelines: A Systematic Scoping Review

BACKGROUND

Professional society guidelines are evidence-based recommendations intended to promote standardized care and improve health outcomes. Amid increased recognition of the role racism plays in shaping inequitable healthcare delivery, many researchers and practitioners have critiqued existing guidelines, particularly those that include race-based recommendations. Critiques highlight how racism influences the evidence that guidelines are based on and its interpretation. However, few have used a systematic methodology to examine race-based recommendations. This review examines hypertension guidelines, a condition affecting nearly half of all adults in the United States (US), to understand how guidelines reference and develop recommendations related to race.

METHODS

A systematic scoping review of all professional guidelines on the management of essential hypertension published between 1977 and 2022 to examine the use and meaning of race categories.

RESULTS

Of the 37 guidelines that met the inclusion criteria, we identified a total of 990 mentions of race categories. Black and African/African American were the predominant race categories referred to in guidelines (n = 409). Guideline authors used race in five key domains: describing the prevalence or etiology of hypertension; characterizing prior hypertension studies; describing hypertension interventions; social risk and social determinants of health; the complexity of race. Guideline authors largely used race categories as biological rather than social constructions. None of the guidelines discussed racism and the role it plays in perpetuating hypertension inequities.

DISCUSSION

Hypertension guidelines largely refer to race as a distinct and natural category rather than confront the longstanding history of racism within and beyond the medical system. Normalizing race as a biological rather than social construct fails to address racism as a key determinant driving inequities in cardiovascular health. These changes are necessary to produce meaningful structural solutions that advance equity in hypertension education, research, and care delivery.

Effect of Tolvaptan in Patients with Chronic Kidney Disease Stage G5, and Impact of Concomitant Use of Thiazide Diuretics: A Retrospective Cohort Study

BACKGROUND

The diuretic effect of tolvaptan, a vasopressin V2 receptor antagonist, in patients with severe renal dysfunction remains poorly characterized. Thiazide diuretics reduce urinary volume (UV) in patients with nephrogenic diabetes insipidus, which lacks V2 receptor function.

OBJECTIVE

This retrospective study investigated the acute urinary effects of tolvaptan in patients with stage G5 chronic kidney disease and congestive heart failure (CHF), and the impact of thiazide diuretics on the urinary effects of tolvaptan.

METHODS

UVs 24 h before and after tolvaptan administration and 30-day dialysis initiation rate were compared between patients with and without thiazide diuretic administration.

RESULTS

Thiazide diuretics were used in 26 of the 106 recruited patients (age 73.4 ± 13.0 years; estimated glomerular filtration rate 8.07 ± 3.13 mL/min/1.73 m²). The pre- and post-tolvaptan 24-h UVs were significantly higher in patients not administered thiazide diuretics (1043.4 ± 645.6 vs. 1422.2 ± 774.0 mL/day; p < 0.001) than in those administered thiazide diuretics (1177.3 ± 686.5 vs. 1173.1 ± 629.1 mL/day; p = 0.93). In a multivariate regression model, thiazide diuretic use was significantly associated with decreased 24-h UV (β coefficient - 486.7, 95% confidence interval [CI] - 674.5 to - 298.8); increased urine osmolality (β coefficient 37.7, 95% CI 17.1-58.4); increased body weight (β coefficient 0.62, 95% CI 0.31-0.92); and increased 30-day dialysis initiation rate (odds ratio 3.40, 95% CI 1.18-9.82) after tolvaptan administration.

CONCLUSIONS

Tolvaptan exhibited significant diuretic effects in patients with CHF, including those with severe renal dysfunction, which were diminished with concomitant thiazide diuretic use.

Black Race Is Associated With Higher Rates of Early-Onset End-Stage Renal Disease and Increased Mortality Following Liver Transplantation

Black race is a risk factor for end-stage renal disease (ESRD). Racial disparities in the risks of early and long-term renal complications after liver transplantation (LT) have not been systematically studied. This study evaluated racial differences in the natural history of acute and chronic renal insufficiency after LT. This was a retrospective single-center cohort study of 763 non-Hispanic White and 181 Black LT recipients between 2008 and 2017. Black race was investigated as an independent predictor of the following outcomes: (1) receipt and duration of early post-LT hemodialysis and (2) time to post-LT ESRD. The interaction of race and post-LT ESRD on survival was also studied. Black recipients had higher rates of pre-LT hypertension (P < 0.001), but diabetes mellitus and renal function before LT were not different by race (all P > 0.05). Overall, 15.2% of patients required early hemodialysis immediately after LT with no difference by race (covariate-adjusted odds ratio, 0.89; P = 0.71). Early dialysis discontinuation was lower among Black recipients (covariate-adjusted hazard ratio [aHR], 0.47; P = 0.02), whereas their rate of post-LT ESRD was higher (aHR, 1.91; P = 0.005). Post-LT survival after ESRD was markedly worse for Black (aHR, 11.18; P < 0.001) versus White recipients (aHR, 5.83; P < 0.001; interaction P = 0.08). Although Black and White LT recipients had comparable pretransplant renal function, post-LT renal outcomes differed considerably, and the impact of ESRD on post-LT survival was greater for Black recipients. This study highlights the need for an individualized approach to post-LT management to improve outcomes for all patients.

Racial Disparities in Bariatric Surgery Complications and Mortality Using the MBSAQIP Data Registry

Background

Racial disparities in postoperative complications have been demonstrated in bariatric surgery, yet the relationship of race to complication severity is unknown.

Study Design

Adult laparoscopic primary bariatric procedures were queried from the 2015 and 2016 MBSAQIP registry. Adjusted logistic and multinomial regressions were used to examine the relationships between race and 30-day complications categorized by the Clavien-Dindo grading system.

Results

A total of 212,970 patients were included in the regression analyses. For Black patients, readmissions were higher (OR = 1.39, p < 0.0001) and the odds of a Grade 1, 3, 4, or 5 complication were increased compared with White patients (OR = 1.21, p < 0.0001; OR = 1.21, p < 0.0001; OR = 1.22, p = 0.01; and OR = 1.43, p = 0.04) respectively. The odds of a Grade 3 complication for Hispanic patients were higher compared with White patients (OR = 1.59, p < 0.0001).

Conclusion

Black patients have higher odds of readmission and multiple grades of complications (including death) compared with White patients. Hispanic patients have higher odds of a Grade 3 complication compared with White patients. No significant differences were found with other races. Specific causes of these disparities are beyond the limitations of the dataset and stand as a topic for future inquiry.

Initiation of Hemodialysis After Eight Years Following the Diagnosis of Stage 5 Chronic Kidney Disease: A Case Report

With the growing global rates of diabetes and hypertension, chronic kidney disease (CKD) appears to be a major contributor to morbidity and all-cause mortality. In recent years, there has been growing controversy regarding the optimal timing for the initiation of hemodialysis in this patient cohort. In this report, we present the case of a 52-year-old female with a 15-year history of CKD who was admitted to the hospital with clinical manifestations of uremia, volume overload, and symptomatic anemia. The patient presented with fatigue, nausea, progressive shortness of breath, and lightheadedness for two weeks, which had limited the activities of daily living. For the past eight years, her estimated glomerular filtration rate (GFR) had ranged from 5 to 15 mL/min/1.73 m2, consistent with kidney failure seen in stage 5 CKD. Prior to her recent admission, the patient had been grossly asymptomatic and had been responsive to medical therapy. After appropriate management with hemodialysis, a transfusion of packed red blood cells, and medication adjustment, the patient was scheduled for maintenance dialysis through an arteriovenous fistula. She had no further complaints and her laboratory abnormalities were found normalized at the six-month follow-up. This case report presents the survival and outcome of a patient with stage 5 CKD, who was only initiated on hemodialysis eight years after her diagnosis.

Explaining trends and variation in timing of dialysis initiation in the United States

The United States Renal Data System (USRDS) registry of end-stage renal disease has often been used to study the timing of dialysis initiation, measured by estimated glomerular filtration rate (eGFR) at dialysis initiation. We conducted an observational study and examined how well variables in the USRDS database explain the trends and variation in eGFR at dialysis initiation.We identified 971,481 patients who initiated dialysis between 1995 and 2012 in the USRDS registry.The mean eGFR at dialysis initiation monotonically rose from 7.7 in 1995 to 11.1 in 2009, and then leveled off to 10.9 mL/min/1.73 m in 2012. The trend of rising, then leveling off was similar across all subgroups studied. Substantial variation in eGFR at dialysis initiation was observed, with standard deviation of 4.38 (95% CI: 2.0-18.4). A total of 11.4% of the total variation occurred across physicians and 88.6% within physicians. Adjustment for measured factors only modestly decreased the total variation. Of the total variance, 10.7% was explained by measured patient-level variables and 1.2% by measured physician and other factors, while 9.2% of physician-level variation and 78.9% of patient-level variation remained unexplained. The extent of variation explained by measured variables was similar over the entire study period.The finding that the majority of variation in eGFR at dialysis initiation is unexplained by measured variables casts doubt on how well eGFR serves as a measure for "timing" of dialysis initiation, and it indicates the need to collect more focused data to gain understanding of factors that affect timing of dialysis initiation in the US.

Timing of Dialysis Initiation: What Has Changed Since IDEAL?

The optimal timing of initiation of maintenance dialysis in patients with end-stage renal disease currently is unknown. This transition period is one of exceptionally high vulnerability for patients; annual mortality rates in stage 5 chronic kidney disease through the first year of maintenance dialysis exceed 20%. The results of the Initiating Dialysis Early and Late (IDEAL) study, a randomized trial that tested the impact of dialysis initiation at two different levels of kidney function on outcomes, showed no significant difference in survival or other patient-centered outcomes between treatment groups. These data have challenged the established paradigm of using estimates of glomerular filtration as the primary guide for initiation of maintenance dialysis and illustrate the compelling need for research to optimize the high-risk transition period from chronic kidney disease to end-stage renal disease. This article reviews the findings of the IDEAL study and summarizes the evolution of research findings, updated clinical practice guidelines, and trends in dialysis initiation practices in the United States in the 6 years since the publication of the results from IDEAL. Complementary strategies to the use of estimated glomerular filtration rate to optimally time the initiation of maintenance dialysis and potentially improve patient-centered outcomes also are considered.

Serum phosphate and social deprivation independently predict all-cause mortality in chronic kidney disease

Background

Hyperphosphataemia is linked to cardiovascular disease and mortality in chronic kidney disease (CKD). Outcome in CKD is also affected by socioeconomic status. The objective of this study was to assess the associations between serum phosphate, multiple deprivation and outcome in CKD patients.

Methods

All adult patients currently not on renal replacement therapy (RRT), with first time attendance to the renal outpatient clinics in the Glasgow area between July 2010 and June 2014, were included in this prospective study. Area socioeconomic status was assessed as quintiles of the Scottish Index of Multiple Deprivation (SIMD). Outcomes were all-cause and cardiovascular mortality and commencement of RRT.

Results

The cohort included 2950 patients with a median (interquartile range) age 67.6 (53.6–76.9) years. Median (interquartile range) eGFR was 38.1 (26.3–63.5) ml/min/1.73 m², mean (±standard deviation) phosphate was 1.13 (±0.24) mmol/L and 31.6 % belonged to the most deprived quintile (SIMD quintile I). During follow-up 375 patients died and 98 commenced RRT. Phosphate ≥1.50 mmol/L was associated with all-cause (hazard ratio (HR) 2.51; 95 % confidence interval (CI) 1.63-3.89) and cardiovascular (HR 5.05; 95 % CI 1.90–13.46) mortality when compared to phosphate 0.90–1.09 mmol/L in multivariable analyses. SIMD quintile I was independently associated with all-cause mortality. Phosphate did not weaken the association between deprivation index and mortality, and there was no interaction between phosphate and SIMD quintiles. Neither phosphate nor SIMD predicted commencement of RRT.

Conclusions

Multiple deprivation and serum phosphate were strong, independent predictors of all-cause mortality in CKD and showed no interaction. Phosphate also predicted cardiovascular mortality. The results suggest that phosphate lowering should be pursued regardless of socioeconomic status.

Examining determinants of patient outcome in a low clearance clinic

BACKGROUND

With an aging population and limited resources, the incidence and prevalence of chronic kidney disease is increasing. We aimed at assessing the impact of the low clearance clinic (LCC) on not only the natural history of patients with deteriorating renal function but also the timing of renal replacement therapy (RRT) and mortality.

METHODS

A retrospective cohort study involving 271 patients who entered the LCC at Hull from July 2007 to December 2010 was conducted. Descriptive analysis based on baseline characteristics was performed and slope-estimated glomerular function rates (eGFR) before and after entry to the LCC were calculated. This aided survival analysis using quartiles and Kaplan-Meier. The change in slope eGFR was the study primary end point, but secondary end points, including mortality and time to RRT, were also measured.

RESULTS

The average length of time within the LCC was 14 months and of those receiving RRT, 61% received this intervention within one year compared with 38% after 1 year. The rapidly declining rate of eGFR prior to entry into the LCC was predictive of both those who would need haemodialysis sooner within a mean of 21 months and of mortality within an average of 26.3 months. Slope eGFRs before and after entry into the LCC showed that 63.3% of patients improved on entry into the LCC.

CONCLUSIONS

The LCC impacts the rate of decline in eGFR. A rapidly declining eGFR prior to entering the LCC was predictive of RRT requirement. There was no significant impact on mortality.

Effect of dialysis initiation timing on clinical outcomes: a propensity-matched analysis of a prospective cohort study in Korea

BACKGROUND

Controversy persists regarding the appropriate initiation timing of renal replacement therapy for patients with end-stage renal disease. We evaluated the effect of dialysis initiation timing on clinical outcomes. Initiation times were classified according to glomerular filtration rate (GFR).

METHODS

We enrolled a total of 1691 adult patients who started dialysis between August 2008 and March 2013 in a multi-center, prospective cohort study at the Clinical Research Center for End Stage Renal Disease in the Republic of Korea. The patients were classified into the early-start group or the late-start group according to the mean estimated GFR value, which was 7.37 ml/min/1.73 m2. The primary outcome was patient survival, and the secondary outcomes were hospitalization, cardiovascular events, vascular access complications, change of dialysis modality, and peritonitis. The two groups were compared before and after matching with propensity scores.

RESULTS

Before propensity score matching, the early-start group had a poor survival rate (P<0.001). Hospitalization, cardiovascular events, vascular access complications, changes in dialysis modality, and peritonitis were not different between the groups. A total of 854 patients (427 in each group) were selected by propensity score matching. After matching, neither patient survival nor any of the other outcomes differed between groups.

CONCLUSIONS

There was no clinical benefit after adjustment by propensity scores comparing early versus late initiation of dialysis.