The Glomerular Filtration Rate (GFR) at Dialysis Initiation and Mortality in Chronic Kidney Disease (CKD) in East Asian Populations: A Meta-analysis

One-Year Mortality after Hemodialysis Initiation: The Prognostic Role of the CHA2DS2-VASc Score

BACKGROUND

CKD is a significant cause of morbidity, cardiovascular and all-cause mortality. CHA2DS2-VASc is a score used in patients with atrial fibrillation to predict thromboembolic risk; it also appears to be useful to predict mortality risk. The aim of the study was to evaluate CHA2DS2-VASc scores as a tool for predicting one-year mortality after hemodialysis is started and for identifying factors associated with higher mortality.

METHODS

Retrospective analysis of patients who started hemodialysis between January 2014 and December 2019 in Centro Hospitalar Universitário Lisboa Norte. We evaluated mortality within one year of hemodialysis initiation. The CHA2DS2-VASc score was calculated at the start of hemodialysis.

RESULTS

Of 856 patients analyzed, their mean age was 68.3 ± 15.5 years and the majority were male (61.1%) and Caucasian (84.5%). Mortality within one-year after starting hemodialysis was 17.8% (n = 152). The CHA2DS2-VASc score was significantly higher (4.4 ± 1.7 vs. 3.5 ± 1.8, p < 0.001) in patients who died and satisfactorily predicted the one-year risk of mortality (AUC 0.646, 95% CI 0.6-0.7, p < 0.001), with a sensitivity of 71.7%, a specificity of 49.1%, a positive predictive value of 23.9% and a negative predictive value of 89.2%. In the multivariate analysis, CHA2DS2-VASc ≥3.5 (adjusted HR 2.24 95% CI (1.48-3.37), p < 0.001) and central venous catheter at dialysis initiation (adjusted HR 3.06 95% CI (1.93-4.85)) were significant predictors of one-year mortality.

CONCLUSION

A CHA2DS2-VASc score ≥3.5 and central venous catheter at hemodialysis initiation were predictors of one-year mortality, allowing for risk stratification in hemodialysis patients.

Muscle mass and estimates of renal function: a longitudinal cohort study

BACKGROUND

Creatinine is the most widely used test to estimate the glomerular filtration rate (GFR), but muscle mass as key determinant of creatinine next to renal function may confound such estimates. We explored effects of 24-h height-indexed creatinine excretion rate (CER index) on GFR estimated with creatinine (eGFR_Cr ), muscle mass-independent cystatin C (eGFR_Cys ), and the combination of creatinine and cystatin C (eGFR_Cr-Cys ) and predicted probabilities of discordant classification given age, sex, and CER index.

METHODS

We included 8076 adults enrolled in the PREVEND study. Discordant classification was defined as not having eGFR_Cr  <60 mL/min per 1.73 m² when eGFR_Cys was <60 mL/min/1.73 m² . Baseline effects of age and sex on CER index were quantified with linear models using generalized least squares. Baseline effects of CER index on eGFR were quantified with quantile regression and logistic regression. Effects of annual changes in CER index on trajectories of eGFR were quantified with linear mixed-effects models. Missing observations in covariates were multiply imputed.

RESULTS

Mean (SD) CER index was 8.0 (1.7) and 6.1 (1.3) mmol/24 h per meter in male and female participants, respectively (P_difference  < 0.001). In male participants, baseline CER index increased until 45 years of age followed by a gradual decrease, whereas a gradual decrease across the entire range of age was observed in female participants. For a 70-year-old male participant with low muscle mass (CER index of 2 mmol/24 h per meter), predicted baseline eGFR_Cr and eGFR_Cys disagreed by 24.7 mL/min/1.73 m² (and 30.1 mL/min/1.73 m² when creatinine was not corrected for race). Percentages (95% CI) of discordant classification in male and female participants aged 60 years and older with low muscle mass were 18.5% (14.8-22.1%) and 15.2% (11.4-18.5%), respectively. For a 70-year-old male participant who lost muscle during follow-up, eGFR_Cr and eGFR_Cys disagreed by 1.5, 5.0, 8.5, and 12.0 mL/min/1.73 m² (and 6.7, 10.7, 13.5, and 15.9 mL/min/1.73 m² when creatinine was not corrected for race) at baseline, 5 years, 10 years, and 15 years of follow-up, respectively.

CONCLUSIONS

Low muscle mass may cause considerable overestimation of single measurements of eGFR_Cr . Muscle wasting may cause spurious overestimation of repeatedly measured eGFR_Cr . Implementing muscle mass-independent markers for estimating renal function, like cystatin C as superior alternative to creatinine, is crucial to accurately assess renal function in settings of low muscle mass or muscle wasting. This would also eliminate the negative consequences of current race-based approaches.

Early as compared to late initiation of twice-weekly hemodialysis and short-term survival among end-stage renal disease patients

INTRODUCTION

The impact of timing of hemodialysis (HD) for end-stage renal disease (ESRD) patients treated with twice-weekly HD remains unclear. We aimed to determine the effects of late initiation of HD on short-term mortality and hospitalization.

METHODS

A multicenter cohort study was conducted in 11 HD centers in Northeastern Thailand (HEmodialysis Network of the NorthEastern Thailand study group). We recruited adult ESRD patients who were treated with twice-weekly HD for more than 3 months and had data on eGFR at HD initiation. Clinical and laboratory values at the time of recruitment were recorded. Late and early (eGFR at start <5 and >5 ml/min/1.73 m² ) initiations were defined. Outcomes were disease-related death (excluding any accidental deaths) and first hospitalization. Data analysis was performed by multivariable cox-regression analysis.

FINDINGS

A total of 407 patients who had data on eGFR at HD initiation (303 in late group and 104 in early group) were included for analysis. There were 56.8% male with a mean age of 55 years. During the 15.1 months of follow-up, there were 27 (6.6%) disease-related deaths. The 1-year survival rate was similar among late and early initiation groups. The incidence density of first hospitalization in the late group was significantly lower than those in the early group (HR adjusted, 0.63; 95% CI, 0.40-0.99, p = 0.047). Among 303 patients who were in the late start group, patients with diabetes had a higher mortality rate (HR, 3.49; 95% CI, 1.40-8.70, p = 0.007) when compared to non-diabetic patients.

DISCUSSION

Early initiation of HD at eGFR >5 ml/min/1.73 m² had no short-term survival benefit compared to the late group in ESRD patients treated with twice-weekly HD for at least 3 months in a resource-limited setting. A survival benefit from an early start of HD was found among diabetic patients.

Sodium-Glucose Cotransporter 2 Inhibitors and Kidney Outcomes: True Renoprotection, Loss of Muscle Mass or Both?

Inhibitors of sodium-glucose cotransporter 2 (SGLT2) have emerged as practice-changing treatments for patients with type 2 diabetes, reducing both the risk of cardiovascular events and kidney events. However, regarding the latter, caution is warranted, as these kidney endpoints are defined using glomerular filtration rate estimations based on creatinine, the non-enzymatic product of creatine residing in muscles. Creatinine-based estimations of the glomerular filtration rate are only valid if the treatment has no effect on changes in muscle mass over time. Yet, circumstantial evidence suggests that treatment with SGLT2 inhibitors does result in a loss of muscle mass, rendering serum creatinine-based kidney endpoints invalid. Currently, it cannot be excluded that the described renoprotective effect of SGLT2 inhibitors is in part or in whole the consequence of a loss of muscle mass. Post-hoc analyses of existing trials or new trials based on kidney function markers independent of muscle mass can provide more definitive answers on the proposed renoprotective effects of SGLT2 inhibitors.

Assessment of dialysis initiation by a fuzzy mathematics equation (ADIFE): a study protocol for a randomised controlled trial

INTRODUCTION

Starting dialysis early or late both result in a low quality of life and a poor prognosis in patients undergoing haemodialysis. However, there remains no consensus on the optimal timing of dialysis initiation, mainly because of a lack of suitable methods to assess variations in dialysis initiation time. We have established a novel equation named DIFE (Dialysis Initiation based on Fuzzy-mathematics Equation) through a retrospective, multicentre clinical cohort study in China to determine the most suitable timing of dialysis initiation. The predictors of the DIFE include nine biochemical markers and clinical variables that together influence dialysis initiation. To externally validate the clinical accuracy of DIFE, we designed the assessment of DIFE (ADIFE) study as a prospective, open-label, multicentre, randomised controlled trial to assess the clinical outcomes among patients who initiate dialysis in an optimal start dialysis group and a late-start dialysis group, based on DIFE.

METHODS AND ANALYSIS

A total of 388 enrolled patients with end-stage renal disease will be randomised 1:1 to the optimal start dialysis group, with a DIFE value between 30 and 35, or the late-start dialysis group, with a DIFE value less than 30, using the Randomization and Trial Supply Management system. Participants will be assessed for changes in signs and symptoms, dialysis mode and parameters, biochemical and inflammatory markers, Subjective Global Assessment, Kidney Disease Quality of Life Short Form, Cognitive Assessment, medical costs, adverse events and concomitant medication at baseline, predialysis visiting stage and postdialysis visiting stage, every 12-24 weeks. The following data will be recorded on standardised online electronic case report forms. The primary endpoint is 3-year all-cause mortality. The secondary endpoints include non-fatal cerebrocardiovascular events, annual hospitalisation rate, quality of life, medical costs and haemodialysis related complications.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Ethics Committee of the First Affiliated Hospital of Dalian Medical University China (registration no: YJ-KY-2017-119) and the ethics committees of all participating centres. The final results of the ADIFE trial will be presented to the study sponsor, clinical researchers and the patient and public involvement reference group. Findings will be disseminated through peer-reviewed journals, Clinical Practice Guidelines and at scientific meetings.

TRIAL REGISTRATION NUMBER

ClinicalTrial.gov. Registry (NCT03385902); pre-results.