Development of a prognostic risk score to predict early mortality in incident elderly Japanese hemodialysis patients

BACKGROUND

Information of short-term prognosis after hemodialysis (HD) introduction is important for elderly patients with chronic kidney disease (CKD) and their families choosing a modality of renal replacement therapy. Therefore, we developed a risk score to predict early mortality in incident elderly Japanese hemodialysis patients.

MATERIALS AND METHODS

We analyzed data of incident elderly HD patients from a nationwide cohort study of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) to develop a prognostic risk score. Candidate risk factors for early death within 1 year was evaluated using multivariate logistic regression analysis. The risk score was developed by summing up points derived from parameter estimate values of independent risk factors. The association between risk score and early death was tested using Cox proportional hazards models. This risk score was validated twice by using an internal validation cohort derived from the JRDR and an external validation cohort collected for this study.

RESULTS

Using the development cohort (n = 2,000), nine risk factors were retained in the risk score: older age (>85), yes = 2, no = 0; sex, male = 2, female = 0; lower body mass index (<20), yes = 2, no = 0; cancer, yes = 1, no = 0; dementia, yes = 3, no = 0; lower creatinine (<6.5 mg/dL), yes = 1, no = 0; lower albumin (<3.0 g/dL), yes = 3, no = 0; normal or high calcium (≥8.5 mg/dL), yes = 1, no = 0; and higher C reactive protein (>2.0 mg/dL), yes = 2, no = 0. In the internal and external validation cohorts (n = 739, 140, respectively), the medium- and high-risk groups (total score, 6 to 10 and 11 or more, respectively) showed significantly higher risk of early death than the low-risk group (total score, 0 to 5) (p<0.001).

CONCLUSION

We developed a prognostic risk score predicting early death within 1 year in incident elderly Japanese HD patients, which may help detect elderly patients with a high-risk of early death after HD introduction.

The medical cost and outcome of desensitization protocol in kidney transplantation recipients with high immunological risks

BACKGROUND

Kidney transplantation is a well-established alternative in renal replacement therapy. Compared with hemodialysis, low-immunological-risk kidney transplantation can reduce the medical treatment costs associated with end-stage renal disease. However, there are few reports on whether high-immunological-risk kidney transplantation reduces the financial burden on governments. We investigated the medical costs of high-immunological-risk kidney transplantation in comparison with the cost of hemodialysis in Japan.

METHODS

We compared the medical costs of high-immunological-risk kidney transplantation with those of hemodialysis. 15 patients who underwent crossmatch-positive and/or donor-specific antibody-positive kidney transplantations between 2020 and 2021 were enrolled in this study. The patients received intravenous immunoglobulin, plasmapheresis, and rituximab as desensitizing therapy.

RESULTS

Acute antibody-mediated rejection was detected in nine (60%) recipients, while there were no indications of graft function deterioration during the follow-up. For each patient, the transplant hospitalization cost was 38 428 ± 8789 USD. However, the cumulative costs were 59 758 ± 10 006 USD and 79 781 ± 16 366 USD, at 12 and 24 months, respectively. Compared with hemodialysis (34 286 USD per year), high-immunological-risk kidney transplantation tends to be expensive in the first year, but the cost is likely to be lower than that of hemodialysis after 3 years.

CONCLUSIONS

Although kidney transplantation is initially expensive compared with hemodialysis, the medical cost becomes advantageous after 3 years even in kidney transplant recipients with high immunological risk.

Impact of Dysmagnesemia on Atrial Fibrillation in Maintenance Hemodialysis Patients: A Nationwide Study

INTRODUCTION

The dose-response relationship between serum magnesium (sMg) and atrial fibrillation (AF) and the contribution of dysmagnesemia to AF among hemodialysis patients remain unknown. Hence, we examined the dose-response correlation between sMg and AF and estimated the extent of the contribution of dysmagnesemia to AF in this population.

METHODS

This was a nationwide cross-sectional study on the Japanese Society for Dialysis Therapy registry, also known as Japanese Renal Data Registry (JRDR), encompassing a nationwide population of dialysis centers, as of the end of 2019. Eligible participants were adult patients undergoing hemodialysis three times per week. The main exposure was sMg, categorized into seven categories (≤1.5, >1.5-≤2, >2-≤2.5, >2.5-≤3, >3-≤3.5, >3.5-≤4, and ≥4.0 mg/dL). The outcome was AF reported by dialysis facilities. The independent contribution to AF was assessed via logistic regression to generate population-attributable fractions, assuming a causal relationship between sMg and AF.

RESULTS

Total 165,926 patients from 2,549 facilities were investigated. AF prevalence was 7.9%. Compared with the reference (>2.5-≤3 mg/dL), lower sMg was associated with increased AF (adjusted odds ratios (ORs) (95% confidence interval, CI) of 1.49 (1.19-1.85), 1.24 (1.17-1.32), and 1.11 (1.06-1.16) for sMg of ≤1.5, >1.5-≤2.0, and >2.0-≤2.5 mg/dL categories, respectively). Elevated sMg was associated with fewer AF (adjusted OR 0.87 [95% CI, 0.79-0.96] for sMg of >3.0-≤3.5 mg/dL). The adjusted population-attributable fraction of lower sMg and higher and lower sMg for AF was 7.4% and 6.9%, respectively. An association did indeed exist between lower sMg and AF, with the lowest percentages of AF at sMg levels above the reference range for the general population.

CONCLUSION

Dysmagnesemia may be an important contributor to AF among adult hemodialysis patients. Further, longitudinal studies are warranted to determine whether sMg correction reduces the AF incidence.

Effect of atherosclerosis on the relationship between atrial fibrillation and ischemic stroke incidence among patients on hemodialysis

In patients undergoing hemodialysis, the impact of atrial fibrillation (AF) through cardiac thromboembolism on the development of ischemic stroke may be influenced by the severity of atherosclerosis present. However, there are no large-scale reports confirming whether the severity of atherosclerosis influences the relationship between AF and stroke development in patients requiring hemodialysis. We aimed to investigate the effects of atherosclerotic disease on the relationship between AF and new-onset ischemic stroke. This nationwide longitudinal study based on dialysis facilities across Japan used data collected from the Japanese Renal Data Registry at the end of 2019 and 2020. The exposure was AF at the end of 2019, identified using a resting 12-lead electrocardiography. The primary outcome was the incidence of cerebral infarction (CI) after 1 year. To examine whether the number of atherosclerotic diseases modified the association between AF and the outcome, we estimated the odds ratios (ORs) using a logistic regression model and then assessed the presence of global interaction using Wald test. Following the study criteria, data from 151,350 patients (mean age, 69 years; men, 65.2%; diabetic patients, 48.7%) were included in the final analysis. A total of 9841 patients had AF (prevalence, 6.5%). Between 2019 and 2020, 4967 patients (3.2%) developed ischemic stroke. The adjusted OR of AF for new-onset CI was 1.5, which showed a decreasing trend with an increasing number of atherosclerotic diseases; the interaction was not significant (P = 0.34). While age, diabetes mellitus, smoking, systolic blood pressure, and serum C-reactive protein concentration were positively associated with CI, intradialytic weight gain, body mass index, and serum albumin level were negatively associated. While we demonstrated the association between AF and new-onset CI among Japanese patients on hemodialysis, we failed to demonstrate the evidence that the association was attenuated with an increasing numbers of atherosclerotic complications.

Minimum-incision transsubclavian transcatheter aortic valve replacement with balloon-expandable valve for dialysis patients

BACKGROUND

Dialysis patients undergoing transcatheter aortic valve replacement (TAVR) face increased risk and have poorer outcomes than non-dialysis patients. Moreover, TAVR in dialysis patients using an alternative approach is considered extremely risky and little is known about the outcomes. We routinely perform minimum-incision transsubclavian TAVR (MITS-TAVR), which is contraindicated for transfemoral (TF) TAVR. This study aimed to evaluate the outcomes of MITS-TAVR compared with those of TF-TAVR in dialysis patients.

METHODS

This single-center, observational study included 79 consecutive dialysis patients who underwent MITS-TAVR (MITS group, n = 22) or TF-TAVR (TF group, n = 57) under regional anesthesia.

RESULTS

The rates of peripheral artery disease (MITS vs. TF, 72.7 % vs. 26.3 %; p < 0.01), shaggy aortas (MITS vs. TF, 63.6 % vs. 5.26 %; p < 0.01), and tortuous aortas (MITS vs. TF, 13.6 % vs. 1.75 %; p = 0.031) were significantly higher in the MITS group. The 30-day mortality was 2.53 % and comparable between the two groups (MITS vs. TF, 4.54 % vs. 1.75 %; p = 0.479). In the MITS group, 14 patients had ipsilateral dialysis fistulas, and three patients had patent in situ ipsilateral internal thoracic artery grafts; however, no vascular complications were observed. Kaplan-Meier survival curves for the two groups showed no significant difference in the survival rate (at 2 years; MITS vs. TF, 77.3 % vs. 68.8 %; p = 0.840) and freedom from cardiovascular mortality (at 2 years; MITS vs. TF, 90.9 % vs. 96.5 %; p = 0.898). The multivariable Cox proportional hazard model also indicated that survival in the MITS group was not significantly different from that in the TF group (hazard ratio 1.48; 95 % confidence interval, 0.77-2.85, p = 0.244). The patency rate of ipsilateral dialysis fistula was 100 % during follow-up.

CONCLUSION

The outcome of MITS-TAVR was comparable to that of TF-TAVR in dialysis patients, despite the higher risk of patient characteristics.

The uric acid-urea distribution volume ratio is a potential marker of hydration status in patients on hemodialysis

The distribution volume of uric acid is affected by the amount of extracellular water (ECW), while urea distribution volume can be considered as total body water (TBW). Thus, the ratio of distribution volumes of uric acid and urea can be paralleled to and be considered as the proxy of ECW/TBW. A total of 108 patients at our facility was included. The uric acid and urea distribution volume ratio (UUVdR) calculated from the single-pool model, which was measured within 1 month of the time when the bioimpedance index was measured. ECW/TBW at the end of the HD session was measured by InBody S10. We investigated the association between the UUVdR and the ECW/TBW values and the factors affecting the residuals of the regression equation. We also evaluated the predictive ability of overhydration or dehydration in randomly selected two groups, i.e., the training group and the validation group. ECW/TBW correlated highly with UUVdR. Multivariate analysis demonstrated that only creatinine and ECW/TBW were significantly associated with regression residuals. The cutoff values of UUVdR for overhydration and dehydration were 0.666 and 0.579, respectively, in the training group. Their AUC were 0.872 and 0.898, respectively. The sensitivity and specificity values in the validation group were 0.571 and 0.868 for overhydration, and 0.444 and 0.953 for dehydration, respectively. UUVdR might be a proxy of hydration status in hemodialysis patients. It may be possible to predict hydration status without dedicated devices in the epidemiological study.

Efficacy of molnupiravir and sotrovimab in Japanese dialysis patients with COVID-19 in clinical practice during the Omicron (BA.1 and BA.2) pandemic

INTRODUCTION

In the present study, the efficacy of sotrovimab and molnupiravir in dialysis patients with COVID-19 was investigated using a registry of COVID-19 in Japanese dialysis patients.

METHODS

Dialysis patients with confirmed SARS-CoV-2 during the COVID-19 (Omicron BA.1 and BA.2) pandemic were analyzed. Patients were classified into four treatment groups: molnupiravir monotherapy (molnupiravir group), sotrovimab monotherapy (sotrovimab group), molnupiravir and sotrovimab combination therapy (combination group), and no antiviral therapy (control group). The mortality rates in the four groups were compared.

RESULTS

A total of 1480 patients were included. The mortality of the molnupiravir, sotrovimab, and combination groups were significantly improved compared to the control group (p < 0.001). Multivariate analysis indicated that antiviral therapy improves the survival of dialysis patients with COVID-19 (hazard ratio was 0.184 for molnupiravir, 0.389 for sotrovimab, and 0.254 for combination groups, respectively).

CONCLUSION

Sotrovimab showed efficacy in Omicron BA.1 but attenuated in BA.2. Molnupiravir also showed efficacy in BA.2, suggesting administration of molnupiravir would be important.

Immediate drop of urine osmolality upon tolvaptan initiation predicts impact on renal prognosis in patients with ADPKD

BACKGROUND AND HYPOTHESIS

Tolvaptan, a vasopressin V2 receptor antagonist, is used for treating autosomal dominant polycystic kidney disease (ADPKD). We focused on changes in urinary osmolality (U-Osm) after tolvaptan initiation to determine whether they were associated with the therapeutic response to tolvaptan.

METHODS

This was a single-centre, prospective, observational cohort study. Seventy-two patients with ADPKD who received tolvaptan were recruited. We analysed the relationship between changes in U-Osm and annual estimated glomerular filtration rate (eGFR) in terms of renal prognostic value using univariable and multivariable linear regression analyses.

RESULTS

The mean value of U-Osm immediately before tolvaptan initiation was 351.8 ± 142.2 mosm/kg H2O, which decreased to 97.6 ± 23.8 mosm/kg H2O in the evening. The decrease in U-Osm was maintained in the outpatient clinic 1 month later. However, the values of U-Osm showed higher variability (160.2 ± 83.8 mosm/kg H2O) than did those in the first evening of tolvaptan administration. Multivariate analysis revealed that the baseline eGFR, baseline urinary protein, and U-Osm change in the evening of the day of admission (initial U-Osm drop) were significantly correlated with the subsequent annual change in eGFR.

CONCLUSIONS

U-Osm can be measured easily and rapidly, and U-Osm change within a short time after tolvaptan initiation may be a useful index for the renal prognosis in actual clinical practice.

Associations of calcium, phosphate and intact parathyroid hormone levels with mortality, residual kidney function and technical failure among patients on peritoneal dialysis

Background

Associations of calcium, phosphate and intact parathyroid hormone (iPTH) levels with outcomes may be different between patients on peritoneal dialysis (PD) and hemodialysis (HD). The aim of the study is to evaluate these associations among PD patients.

Methods

In this prospective cohort study on the Japan Renal Data Registry, adults on PD at the end of 2009 were included. The observation period was until the end of 2018 and the data were censored at the time of transplantation or transition to HD. Exposures were time-averaged or time-dependent albumin-corrected calcium (cCa), phosphate and iPTH levels. Outcomes were all-cause and cardiovascular mortality, transition to HD and urine output. Data were analyzed using Cox regression models or linear mixed-effects models and the results were shown as cubic spline curves.

Results

Among 7393 patients, 590 deaths and 211 cardiovascular deaths were observed during a median follow-up of 3.0 years. Higher cCa and phosphate levels were associated with higher mortality. Lower cCa levels were associated with a faster decline, whereas lower phosphate was associated with a slower decline in urine output. Lower phosphate and iPTH levels were associated with a lower incidence of transition to HD.

Conclusions

Among PD patients, the observed associations of cCa, phosphate and iPTH with mortality, residual kidney function and technical failure suggest that avoiding high cCa, phosphate and iPTH levels might improve outcomes.

Citric acid-based bicarbonate dialysate attenuates aortic arch calcification in maintenance hemodialysis patients: a retrospective observational study

BACKGROUND

Progression of aortic calcification is associated with all-cause and cardiovascular mortality in hemodialysis patients. Blood calciprotein particle (CPP) levels are associated with coronary artery calcification and were reported to be inhibited when using citric acid-based bicarbonate dialysate (CD). Therefore, this study aimed to examine the effect of CD on the progression of the aortic arch calcification score (AoACS) and blood CPP levels in hemodialysis patients.

METHODS

A 12-month retrospective observational study of 262 hemodialysis patients was conducted. AoACS was evaluated by calculating the number of calcifications in 16 segments of the aortic arch on chest X-ray (minimum score is 0; maximum score is 16 points). The patients were divided into the following groups according to their baseline AoACS: grade 0, AoACS = 0 points; grade 1, AoACS 1-4 points; grade 2, AoACS 5-8 points; grade 3, AoACS 9 points or higher. Patients on bisphosphonates or warfarin or with AoACS grade 3 were excluded. Progression, defined as ΔAoACS (12-month score - baseline score) > 0 points, was compared between the CD and acetic acid-based bicarbonate dialysate (AD) groups before and after adjusting the background using propensity score matching.

RESULTS

The AoACS progression rate was significantly lower in the CD group than in the AD group (before matching: P = 0.020, after matching: P = 0.002). Multivariate logistic regression analysis showed that CD was significantly associated with AoACS progression (odds ratio 0.52, 95% confidence interval 0.29‒0.92, P = 0.025).

CONCLUSION

CD may slow the progression of vascular calcification in hemodialysis patients.

Effectiveness of SARS-CoV-2 vaccines on hemodialysis patients in Japan: A nationwide cohort study

INTRODUCTION

This study compared the outcomes of dialysis patients who received SARS-CoV-2 vaccine with those who did not use data from the Japanese COVID-19 registry.

METHODS

A total of 1260 dialysis patients with confirmed positive SARS-CoV-2 infection was included in this study. Patients were divided into two groups: patients who experienced breakthrough infection and those who were unvaccinated. The need of oxygen supplementation and mortality risks were compared using multivariate logistic regression analysis.

RESULTS

The mortality rate was 24.2% in unvaccinated patients and 8.6% in breakthrough patients. The odds ratio of need of oxygen supplementation in the breakthrough patients relative to unvaccinated patients was 0.197. The hazard ratio of mortality in the breakthrough patients relative to unvaccinated patients was 0.464.

CONCLUSION

Our prospective observational study showed that SRAS-CoV-2 vaccination in hemodialysis patients is vital for reducing need of oxygen supplementation and mortality risk.

Physical function management for elderly dialysis patients: prevention and improvement of frailty and disability

Frailty has become an emerging public health problem in the aging society and is regarded as a state of vulnerability to developing increased dependency and/or mortality when exposed to a stressor. As the proportion of elderly dialysis patients is increasing worldwide, frailty has recently influenced on the clinical outcomes among those patients also caused great attention. The prevalence of frailty among dialysis patients has ranged from 3.0- to 10-fold higher than in community-dwelling elderly. Since frailty has been found to be associated with higher mortality, independent of clinical characteristics and comorbidity, interventions to improve frailty have the potential to contribute to better quality of life and lower mortality among dialysis patients. Moreover, clinical research should be focused on the possibility that early rehabilitation of dialysis patients might improve poor outcomes. Current clinical question should aim to take an appropriate strategy to address frailty, including identifying the optimal timing for intervention.

Glycated albumin to glycated hemoglobin ratio and mortality in diabetic patients on dialysis: a new association

Hemoglobin A1c (A1c) and glycated albumin (GA) are two blood glycated proteins commonly used to monitor glycemic control in dialysis patients with diabetes. However, little is known about the association between the GA/A1c ratio and mortality in these populations. Here, we examine these associations using a nationwide cohort.

We enrolled 28 994 dialysis patients with diabetes who met our inclusion criteria (female, 32.9%; mean age, 67.4 ± 11.6 years; mean dialysis duration, 6.3 ± 5.8 years). After dividing the patients into groups based on GA/A1c quantiles and adjusting for 18 potential confounders, adjusted hazard ratios and 95% confidence limits were calculated for 3-year mortality and cause-specific mortalities. Additionally, propensity score matching analyses were used to compare mortalities between the low and high GA/A1c groups.

After adjusting for possible confounders, significantly increased mortality was found in patients with GA/A1c ratios of 3.6–4.0 (HR 1.21 (1.10–1.34)) or higher (HR 1.43 (1.30–1.58)) than in those with GA/A1c ratios of 3.0–3.3. The risks of infectious and cardiovascular death were higher in these patients regardless of their nutritional status. In the propensity score matching analyses, significantly increased mortality was consistently found in those with a higher ratio (≥3.3) (HR 1.23 (1.14–1.33)) than in those with a lower ratio.

The GA/A1c ratio was significantly associated with 3-year mortality, especially infectious and cardiovascular mortality, in dialysis patients with diabetes. This ratio may be a promising new clinical indicator of survival in these patients, independent of their current glycemic control and nutritional markers.

Investigation for the efficacy of COVID-19 vaccine in Japanese CKD patients treated with hemodialysis

Background

Dialysis patients are predisposed to severe disease and have a high mortality rate in coronavirus disease 2019 (COVID-19) due to their comorbidities and immunocompromised conditions. Therefore, dialysis patients should be prioritized for vaccination. This study aimed to examine how long the effects of the vaccine are maintained and what factors affect antibody titers.

Methods

Hemodialysis patients (HD group) and age- and sex-matched non-dialysis individuals (Control group), receiving two doses of BNT162b2 vaccine, were recruited through the Japanese Society for Dialysis Therapy (JSDT) Web site in July 2021. Anti-SARS-CoV-2 immunoglobulin (IgG) (SARS-CoV-2 IgG titers) was measured before vaccination, 3 weeks after the first vaccination, 2 weeks after the second vaccination, and 3 months after the second vaccination, and was compared between Control group and HD group. Factors affecting SARS-CoV-2 IgG titers were also examined using multivariable regression analysis and stepwise regression analysis (least AIC). In addition, we compared adverse reactions in Control and HD groups and examined the relationship between adverse reactions and SARS-CoV-2 IgG titers.

Results

Our study enrolled 123 participants in the Control group (62.6% men, median age 67.0 years) and 206 patients in the HD group (64.1% men, median age 66.4 years). HD group had significantly lower SARS-CoV-2 IgG titers at 3 weeks after the first vaccination (p < 0.0001), 2 weeks after second vaccination (p = 0.0002), and 3 months after the second vaccination (p = 0.045) than Control group. However, the reduction rate of SARS-CoV-2 IgG titers between 2 weeks and 3 months after the second vaccination was significantly smaller in HD group than in Control (p = 0.048). Stepwise regression analysis revealed that dialysis time was identified as the significant independent factors for SARS-CoV-2 IgG titers at 2 weeks after the second vaccination in HD group (p = 0.002) and longer dialysis time resulted in higher maximum antibody titers. The incidences of fever and nausea after the second vaccination were significantly higher in the HD group (p = 0.039 and p = 0.020). Antibody titers in those with fever were significantly higher than those without fever in both groups (HD: p = 0.0383, Control: p = 0.0096).

Conclusion

HD patients had significantly lower antibody titers than age- and sex-matched non-dialysis individuals over 3 months after vaccination. Dialysis time was identified as a factor affecting SARS-CoV-2 IgG titers in HD group, with longer dialysis time resulting in higher maximum SARS-CoV-2 IgG titers.

Committee report: Questionnaire survey on the treatment of COVID-19 in patients receiving dialysis therapy

Background

Patients with coronavirus disease 2019 (COVID-19) who receive dialysis therapy develop more severe disease and have a poorer prognosis than patients who do not. Although various data on the treatment of patients not receiving dialysis therapy have been reported, clinical practice for patients on dialysis is challenging as data is limited. The Infection Control Committee of the Japanese Society for Dialysis Therapy decided to clarify the status of treatment in COVID-19 patients on dialysis.

Methods

A questionnaire survey of 105 centers that had treated at least five COVID-19 patients on dialysis was conducted in August 2021.

Results

Sixty-six centers (62.9%) responded to the questionnaire. Antivirals were administered in 27.7% of facilities treating mild disease (most patients received favipiravir) and 66.7% of facilities treating moderate disease (most patients with moderate or more severe conditions received remdesivir). Whether and how remdesivir is administered varies between centers. Steroids were initiated most frequently in moderate II disease (50.8%), while 43.1% of the facilities initiated steroids in mild or moderate I disease. The type of steroid, dose, and the duration of administration were generally consistent, with most facilities administering dexamethasone 6 mg orally or 6.6 mg intravenously for 10 days. Steroid pulse therapy was administered in 48.5% of the facilities, and tocilizumab was administered in 25.8% of the facilities, mainly to patients on ventilators or equivalent medications, or to the cases of exacerbations. Furthermore, some facilities used a polymethylmethacrylate membrane during dialysis, nafamostat as an anticoagulant, and continuous hemodiafiltration in severe cases. There was limited experience of polymyxin B-immobilized fiber column-direct hemoperfusion and extracorporeal membrane oxygenation. The discharge criteria for patients receiving dialysis therapy were longer than those set by the Ministry of Health, Labor and Welfare in 22.7% of the facilities.

Conclusions

Our survey revealed a variety of treatment practices in each facility. Further evidence and innovations are required to improve the prognosis of patients with COVID-19 receiving dialysis therapy.

An Investigation into Possible Sex Differences in Association of Hemoglobin with Survival Among Hemodialysis Patients in the J-DOPPS Cohort

AIMS

Lower hemoglobin levels are common among females without kidney diseases. However, little is known about the sex-specific management of anemia in hemodialysis patients.

METHODS

This prospective cohort study investigated the role of sex differences in the association between categorical baseline or time-varying hemoglobin levels and all-cause mortality via cox regression using data from 6890 patients the Japan Dialysis Outcomes and Practice Patterns Study (J-DOPPS, 2005-2015). Likelihood ratio tests were used to evaluate the effect modification of sex on the relationship between hemoglobin and mortality.

RESULTS

A total of 781 patients died during the median follow-up of 31 months. Mortality risk, adjusted for case mix, varied between five hemoglobin categories, with the highest category (≥12 g/dl) having a hazard ratio of 0.73 (0.41-1.29) for females and 2.02 (1.03-3.95) for males versus 10-10.9 g/dl. Despite this difference, the p-value comparing the overall among males versus females was.35. Similar associations were observed in models stratified by patient age (<75 years), time on dialysis (≤1 year), and models lagging the hemoglobin exposure.

CONCLUSIONS

The results based on this sample of Japanese hemodialysis patients did not support the hypothesis that the association between hemoglobin and survival differed by sex. We also could not conclude that the association was identical, as the parameter estimates are consistent with male patients having a relatively greater mortality risk than female patients at higher hemoglobin levels. More detailed investigations into the effects of higher hemoglobin levels by sex might help better understand strategies for anemia management.

The Japanese Society for Apheresis clinical practice guideline for therapeutic apheresis

Most of the diseases for which apheresis therapy is indicated are intractable and rare, and each patient has a different background and treatment course prior to apheresis therapy initiation. Therefore, it is difficult to conduct large-scale randomized controlled trials to secure high-quality evidence. Under such circumstances, the American Society for Apheresis (ASFA) issued its guidelines in 2007, which were repeatedly revised until the latest edition in 2019. The ASFA guidelines are comprehensive. However, in the United States, a centrifugal separation method is mainly used for apheresis, whereas the mainstream procedure in Japan is the membrane separation method. The target diseases and their backgrounds are different from those in Japan. Due to these differences, the direct adoption of the ASFA guidelines in Japanese practice creates various problems. One of the features of apheresis in Japan is the development of treatment methods using hollow-fiber devices such as double filtration plasmapheresis (DFPP) and selective plasma exchange and adsorption-type devices such as polymyxin B-immobilized endotoxin adsorption columns. Specialists in emergency medicine, hematology, collagen diseases/rheumatology, respiratory medicine, cardiovascular medicine, gastroenterology, neurology, nephrology, and dermatology who are familiar with apheresis therapy gathered for this guideline, which covers 86 diseases. In addition, since apheresis therapy involves not only physicians but also clinical engineers, nurses, dieticians, and many other medical professionals, this guideline was prepared in the form of a worksheet so that it can be easily understood at the bedside. Moreover, to the clinical purposes, this guideline is designed to summarize apheresis therapy in Japan and to disseminate and further develop Japanese apheresis technology to the world. As diagnostic and therapeutic techniques are constantly advancing, the guidelines need to be revised every few years. In order to ensure the high quality of apheresis therapy in Japan, both the Japanese Society for Apheresis Registry and the guidelines will be inseparable.

Safety and efficacy of cell-free and concentrated ascites reinfusion therapy against cirrhotic ascites in comparison with malignancy-related ascites

BACKGROUND AND AIM

Cell-free and concentrated ascites reinfusion therapy (CART) has been performed against cirrhotic ascites, one of the most common complications seen in patients with decompensated cirrhosis. The aim of this study is to investigate its safety and efficacy, and differences in clinical profiles from CART against malignancy-related ascites with different pathological background.

METHODS

The present investigation involved a sub-analysis of data obtained from a prospective observational study of CART performed at 22 centers. The condition of each procedure, therapeutic options, laboratory data, performance status, dietary intake, and abdominal circumference of participants were analyzed. Clinical parameters were compared between before and after CART, with or without albumin infusion, and also primary diseases including cirrhosis and malignant disease.

RESULTS

Between January 2014 and January 2015, a total of 48 and 275 CART procedures were performed in patients with cirrhosis and malignancies. In cirrhotic patients, serum albumin concentration increased significantly in groups both with and without concomitant albumin infusion (P = 0.002 and P = 0.023), and no significant difference in CART interval was seen between these groups (P = 0.393). CART interval was not significantly different between cirrhosis and malignancy groups (P = 0.334). Dietary intake significantly improved after CART in both groups (P = 0.043 and P < 0.001). Adverse events were with no clinical significance as observed in patients with malignancies.

CONCLUSIONS

Cell-free and concentrated ascites reinfusion therapy was performed safely and effectively in patients with ascites related to decompensated cirrhosis and offers the potential efficacy to maintain plasma colloid osmotic pressure after paracentesis as well as in patients with malignancy.

Survival and predictive factors in dialysis patients with COVID-19 in Japan: a nationwide cohort study

Background

The Japanese Association of Dialysis Physicians, the Japanese Society for Dialysis Therapy, and the Japanese Society of Nephrology jointly established COVID-19 Task Force Committee and began surveying the number of newly infected patients.

Methods

This registry of the COVID-19 Task Force Committee was used to collect data of dialysis patients; a total of 1010 dialysis patients with COVID-19 were included in the analysis. Overall survival of patients was investigated with stratification by age group, complication status, and treatment. In addition, predictive factors for mortality were also investigated. The overall survival was estimated by Kaplan–Meier methods and compared by using log-rank test. Multivariate analysis was performed to identify the risk factor of mortality. For all statistical analyses, p < 0.05 was considered to be statistically significant.

Results

The mortality risk was increased with age (p < 0.001). The mortality risk was significantly higher in patients with peripheral arterial disease (HR: 1.49, 95% CI 1.05–2.10) and significantly lower in patients who were treated with remdesivir (HR: 0.60, 95% CI 0.37–0.98). Multivariate analysis showed increased risk of mortality with increment in BMI, and increment in CRP, and decreased risk with increment in albumin.

Conclusion

Dialysis patients have a high severity of illness and a high risk of mortality in cases of COVID-19. Treatment with remdesivir might be effective in shortening the duration of hospitalization and reducing the risk of mortality.

Annual dialysis data report of the 2018 JSDT Renal Data Registry: dementia, performance status, and exercise habits

According to the annual survey of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) conducted at the end of 2018, there were a total of 339,841 patients receiving dialysis (hereinafter, dialysis patients) in Japan. The survey included questions regarding the presence/absence of dementia, the performance status (PS), and the exercise habits of individual patients. The survey revealed that 10.8% of all dialysis patients had dementia (1.8% in the age group of less than 65 years, 6.8% in the age group of 65–74 years, and 22.7% in the age group of 75 years or older). These prevalences of dementia were approximately equal to those estimated from the survey conducted in 2010. Regarding PS, the percentage of patients with lower activity levels tended to be relatively high among patients who were less than 15 years old and those who were 60 years old or older. Concerning the exercise habits of dialysis patients, the percentage of patients who were classified as “not at all or hardly” in response to the question about exercise habit was the highest (60–80%) of all the exercise habit classifications in each of the age groups analyzed.

Nationwide survey of the coronavirus disease 2019 prevention and treatment systems for kidney disease patients: a study of Japanese Society of Nephrology-certified educational facilities

Background

There are no reports of a large-scale survey on the infection prevention measures against coronavirus disease 2019 (COVID-19) in nephrology facilities. This study investigated the facility-level nephrology practices adopted during the COVID-19 pandemic and their associated challenges. Additionally, the treatment patterns and outcomes of chronic kidney disease (CKD) patients with COVID-19 were reviewed.

Methods

We conducted a nationwide questionnaire survey of 704 educational facilities that were certified by the Japanese Society of Nephrology (JSN) from October 20, 2020 to November 16, 2020. The questionnaire reviewed the facility characteristics, infection prevention measures taken during routine nephrology practice, impact of COVID-19 on nephrology practice, experiences in managing CKD patients with COVID-19, and nosocomial transmission in the nephrology unit.

Results

Of the 347 facilities that responded, 95.1% checked outpatients’ body temperatures and COVID-19 symptoms at their visits. To reduce face-to-face contact, 80% and 70% of the facilities lengthened the intervals between outpatient visits and introduced online/telephonic consultations, respectively. As a result, more than half of the hospitals experienced a decrease in the numbers of outpatients and inpatients (64% and 50%, respectively). During the study period, 347 facilities managed 479 CKD patients with COVID-19. Oxygen administration and mechanical ventilation were performed for 47.8% and 16.5% of the patients, respectively, with a 9.2% total mortality rate.

Conclusion

This survey demonstrated that JSN-certified educational nephrology facilities adopted multiple measures to manage the COVID-19 pandemic; however, they faced several challenges. Sharing these experiences could standardize these approaches and prepare us better for the future.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10157-021-02082-z.

Infection prevention measures for patients undergoing hemodialysis during the COVID-19 pandemic in Japan: a nationwide questionnaire survey

Background

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic affecting a variety of medical treatments, including hemodialysis. This study aims to investigate the implementation of infection control measures, to examine the shortage of personal protective equipment (PPE) and disinfectants, and to quantify the number of nosocomial COVID-19 transmissions in hemodialysis facilities in Japan during the pandemic.

Methods

We conducted a nationwide questionnaire survey between 20 October and 16 November 2020 (i.e., between the "second wave" and "third wave" in Japan) in the 4198 dialysis facilities of the Japanese Association of Dialysis Physicians and the Japanese Society for Dialysis Therapy. A total of 2227 facilities (53.0%) responded. The questionnaire consisted of (i) characteristics of facilities, (ii) infection prevention measures in routine dialysis practices, (iii) shortage of PPE, (iv) feasibility of various isolation measures, and (v) nosocomial transmission.

Results

Half of the responding facilities were hospitals with multiple departments, and the other half were clinics specialized in dialysis. Several infection prevention measures such as health checks of staff and patients, donning of masks before and after hemodialysis, and disinfection of frequently contacted areas were implemented during the COVID-19 pandemic. There was a significant improvement in the implementation rate of these measures during the pandemic, compared to before it, which reached over 90%. More than half of the facilities reported a shortage of disposable masks (67.2%) and hand sanitizer alcohol (56.7%). Isolation of COVID-19 patients in private rooms was possible only in 52.7% of the facilities. The majority of facilities (73.3%) could not accept COVID-19 dialysis patients due to lack of space and manpower. Nosocomial transmission of COVID-19 occurred in 4.0% of the facilities. Of those infected, 51.9% were staff.

Conclusions

This survey revealed that most hemodialysis facilities in Japan had improved implementation of infection control measures and had shortage of PPEs and disinfectants, though some facilities did not implement infection prevention measures adequately, mainly due to the limited space of the facility. It may be recommended that each facility immediately establishes isolation measures to prepare for the pandemic of COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41100-021-00350-y.

2018 annual dialysis data report of the JSDT Renal Data Registry: patients with hepatitis

Abstract

According to the annual survey of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) conducted at the end of 2018, a total of 339,841 patients were receiving dialysis (hereinafter, dialysis patients) in Japan. This survey included an investigation of individual test results for hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) antibody (HCV-Ab), HCV-RNA, and serum alanine aminotransferase (ALT) (glutamic pyruvic transaminase [GPT]). The survey revealed that among dialysis patients in Japan, the prevalence of HBsAg positivity was 1.38% and the prevalence of HCV-Ab positivity was 4.7% at the end of 2018, both of which were markedly lower than the corresponding rates documented in 2007 (9.8% and 4.7%, respectively). The proportion of HCV-RNA-positive patients among all HCV-Ab-positive patients was 37.5%, which was also markedly lower than the percentage recorded in 2007 (64.0%). The prevalence of HBsAg positivity tended to increase as the dialysis vintage increased. The prevalence of HCV-Ab positivity was also not correlated with the dialysis vintage during the first 30 years of dialysis; however, it tended to increase as the dialysis vintage increased beyond the 30th year.

Trial registration

University hospital Medical Information Network (UMIN) Clinical Trials Registry, UMIN000018641. The JRDR was approved by the ethics committee of the JSDT (approval number 1-3) and was registered on August 8, 2015 (accessed June 2, 2020).

Association between Dipeptidyl Peptidase-4 Inhibitor Prescription and Erythropoiesis-Stimulating Agent Hyporesponsiveness in Hemodialysis Patients with Diabetes Mellitus

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) has been hypothesized to improve responsiveness to erythropoiesis-stimulating agent (ESA). We aimed to describe the trend in DPP-4 inhibitor prescription patterns and assess the association between DPP-4 inhibitor prescription and ESA hyporesponsiveness (eHypo) in Japanese hemodialysis (HD) patients with diabetes mellitus (DM).

METHODS

We analyzed data from the Japan Dialysis Outcomes and Practice Patterns Study phase 4-6 (2009-2017) on patients with DM who underwent HD thrice per week for at least 4 months. The primary exposure of interest was having a DPP-4 inhibitor prescription. The primary analysis outcomes were a binary indicator of eHypo (mean hemoglobin <10 and mean ESA dose >6,000 units/week over 4 months) and the natural log-transformed ESA resistance index (ERI). We used conditional logistic regression to compare within-patient changes in eHypo before and after initial DPP-4 inhibitor prescription. We used linear generalized estimating equation models to compare continuous ERI outcomes while accounting for within-patient repeated measurements with an exchangeable correlation structure.

RESULTS

There was a monotonic increase in DPP-4 inhibitor prescription according to study year up to 20% in 2017. Moreover, 12.8% of patients with a DPP-4 inhibitor prescription were ESA hyporesponsive before the initial DPP-4 inhibitor prescription. After DPP-4 inhibitor prescription, the odds of eHypo and mean log-ERI remained unchanged in the whole cohort of our study. The interaction analysis of DPP-4 inhibitor and sideropenia showed that DPP-4 inhibitors attenuated eHypo in the patients without iron deficiency.

CONCLUSION

Our findings indicate a recent increase in DPP-4 inhibitor prescription among Japanese HD patients with DM. DPP-4 inhibitors could improve ERI in patients undergoing HD without iron deficiency.

Medical Director Practice of Advising Increased Dietary Protein Intake in Hemodialysis Patients With Hyperphosphatemia: Associations With Mortality in the Dialysis Outcomes and Practice Patterns Study

OBJECTIVES

Patients undergoing hemodialysis (HD) may have poor nutritional status and hyperphosphatemia. Nephrologists sometimes manage hyperphosphatemia by prescribing phosphate binders and/or recommending restriction of dietary phosphate including protein-rich foods; the later may, however, adversely affect nutritional status.

DESIGN AND METHODS

The analysis includes 8805 HD patients on dialysis ≥ 120 days in 12 countries in Dialysis Outcomes and Practice Patterns Study (DOPPS) phase 4 (2009-2011), from 248 facilities. The primary exposure variable was response to the following question: "For patients with serum albumin 3.0 g/dL and phosphate 6.0 mg/dL, do you recommend to (A) increase or (B) decrease/no change in dietary protein intake (DPI)?". The association between medical director's practice of recommending an increase in DPI and all-cause mortality was analyzed with Cox regression adjusted for potential confounders. Linear and logistic regressions were used to model the cross-sectional associations between DPI advice practice and intermediate markers of patient nutrition.

RESULTS

Median follow-up was 1.6 years. In the case scenario, 91% of medical directors in North America had a practice of recommending DPI increase compared to 58% in Europe (range = 36%-83% across 7 countries) and 56% in Japan. The practice of advising DPI increase was weakly associated with lower mortality [HR (95% CI): 0.88 (0.76-1.02)]. The association tended to be stronger in patients with age 70+ years [HR (95% CI): 0.82 (0.69-0.97), P = .12 for interaction]. The practice of advising DPI increase was associated with 0.276 mg/dL higher serum creatinine levels (95% CI: 0.033-0.520) after adjustment for case mix.

CONCLUSIONS

Medical director's practice of recommending an increase in DPI for HD patients with low albumin and high phosphate levels was associated with higher serum creatinine levels and potentially lower all-cause mortality. To recommend protein intake liberalization in parallel with phosphate management by physicians may be a critical practice for better nutritional status and outcomes in HD patients.

Clinical usefulness of cell-free and concentrated ascites reinfusion therapy (CART) in combination with chemotherapy for malignant ascites: a post-marketing surveillance study

BACKGROUND

Cell-free and concentrated ascites reinfusion therapy (CART) has been suggested to be able to treat malignant ascites more safely and effectively with chemotherapy because of its ability to retain serum protein and albumin. Although the characteristics of cancer types and CART and the clinical implications of combination therapy with antitumor agents are becoming widespread, there are limited reports on its efficacy and complications.

METHODS

In this prospective observational national post-marketing study, 128 patients with malignancies received 300 CART sessions at 22 centers. After excluding other malignancies, the patients were divided into four groups: gynecological malignancies with chemotherapy (GYC+; 18 cases and 36 times) and without chemotherapy (GYC-; 35 cases and 52 times), and gastrointestinal malignancies with chemotherapy (GIC+; 8 cases and 16 times) and without chemotherapy (20 cases and 58 times).

RESULTS

There were significant reductions in the body weight in all groups and significant reductions in abdominal circumference and significant improvements in the diet and Eastern Cooperative Oncology Group performance status only in the GYC+ group. The total serum protein and albumin increased significantly in all groups, except for the GIC+ group, before and after CART. There was no significant difference in the presence or absence of antitumor medication.

CONCLUSION

With CART, there were differences in the improvement of the clinical symptoms between malignancy groups. The combination of CART and antineoplastic agents may be as safe as CART alone in cases of exudative malignant ascites.

Granulocyte and monocyte apheresis therapy for patients with active ulcerative colitis associated with COVID-19

Coronavirus disease 2019 (COVID-19), caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is now a pandemic. Although several treatment guidelines have been proposed for patients who have both inflammatory bowel disease and COVID-19, immunosuppressive therapy is essentially not recommended, and the treatment options are limited. Even in the COVID-19 pandemic, adjuvant adsorptive granulocyte and monocyte apheresis may safely bring ulcerative colitis (UC) into remission by removing activated myeloid cells without the use of immunosuppressive therapy. Our patient was a 25-year-old Japanese male with UC and COVID-19. This is the first case report of the induction of UC remission with granulocyte and monocyte apheresis treatment for active UC associated with COVID-19.

Impact of visceral fat area in patients with chronic kidney disease

Longitudinal studies evaluating the association between visceral fat area (VFA) and kidney function decline in patients with chronic kidney disease (CKD) are limited, and little is known about VFA interactions contributing to the kidney prognosis (e.g. interactions between VFA ≥ 100 cm² and age, sex, and CKD category). In this study, we stratified patients with CKD according to VFA category, as well as age, sex, CKD category, hyperglycemia, and diabetes mellitus, and determined the ability of obesity-related indicators (body mass index, waist circumference, subcutaneous fat area, visceral-to-subcutaneous fat ratio) to predict the renal prognosis. Kidney outcomes (≥ 50% estimated glomerular filtration rate decline or end-stage kidney disease) were examined in 200 patients with CKD (median follow-up, 12.3 years). On multivariable Cox analysis, an increase in VFA (10-cm² increase) was significantly associated with kidney outcomes in the entire cohort, and VFA was significantly associated with kidney disease progression even in the VFA < 100 cm² sub-cohort. Interestingly, the hazard ratio (HR) was higher for VFA (10-cm² increase) than for the VFA ≥ 100 cm² sub-cohort (HR 1.33 vs. 1.07). Overall, VFA was found to be the most versatile obesity-related indicator associated with kidney disease progression. VFA was associated with the primary outcome in the sub-cohorts of CKD stages 1-2, hyperglycemia, and diabetes mellitus. A high VFA was a significant kidney prognostic factor in the entire CKD cohort, with greater significance in patients with VFA < 100 cm² than in patients with VFA ≥ 100 cm². Our results may provide new insights into strategies for treating CKD.

Sex Differences in Time-Series Changes in Pseudo-R2 Values Regarding Hyperuricemia in Relation to the Kidney Prognosis

Studies on sex differences in time-series changes in pseudo-R² values regarding hyperuricemia (HU) in relation to the kidney prognosis among patients with chronic kidney disease (CKD) are scant. The kidney prognosis was evaluated in 200 patients with CKD (median follow-up, 12.3 years). Survival analyses and logistic regression analyses were conducted, generating time-series pseudo-R² values. We used four definitions of HU according to serum uric acid (SUA) levels (HU6, SUA ≥ 6.0 mg/dL; HU7, SUA ≥ 7.0 mg/dL; HU8, SUA ≥ 8.0 mg/dL) and antihyperuricemic agent use to calculate the mean and percentage of the change in pseudo-R² values from the 6th year until the end of the study (6Y–End Mean and 6Y–End Change, respectively). The multivariable Cox regression analysis showed that HU7 was significantly associated with kidney outcomes. When stratified by sex, the 6Y–End Mean was clearly higher in women than in men for all HU definitions, with the highest value (0.1755) obtained for HU7 in women. The pseudo-R² values for HU6 in women showed an increasing pattern, with a 6Y–End Change of 11.4%/year. Thus, it may be clinically meaningful to consider sex differences in the time-series pseudo-R² values regarding HU and kidney outcomes.

Long-Term Beneficial Effects of Tonsillectomy on Patients with Immunoglobulin A Nephropathy

BACKGROUND

Tonsillectomy may treat IgA nephropathy (IgAN) by reducing the levels of galactose-deficient IgA1. Therefore, we aimed to analyze the long-term effects of tonsillectomy on patients with IgAN, as an initial treatment and as a treatment at any time in their lives.

METHODS

In this retrospective cohort analysis, 1147 patients with IgAN were grouped according to whether they had undergone tonsillectomy at any time, >1 year after renal biopsy (study 1), or within 1 year after renal biopsy (study 2). The patients were propensity-score matched or divided into four groups according to their proteinuria and renal function. The 20-year renal survival rates were evaluated until serum creatinine levels doubled (primary end point) and ESKD occurred (secondary end point).

RESULTS

Patients in both studies had similar background characteristics after propensity score matching. In study 1, the renal survival rates for the primary and secondary end points were significantly higher for patients who underwent tonsillectomy at any time or >1 year after renal biopsy compared with those who did not. In study 2, the renal survival rates for the primary and secondary end points were significantly higher for patients who underwent tonsillectomy soon after renal biopsy compared with those who did not (primary end point, 98% versus 69%, P=0.001; secondary end point, 100% versus 75%, P=0.0001). A stratified analysis showed that significant treatment efficacy was observed for patients with proteinuria >1.0 g/d. Multivariate Cox regression analyses showed that tonsillectomy was associated with disease progression (hazard ratio, 0.27; P=0.04). Complications associated with tonsillectomy occurred in 8% of patients.

CONCLUSIONS

Among patients with IgAN, tonsillectomy at any time of life, or soon after renal biopsy, prevents disease progression, and the procedure is relatively safe.

Visceral to subcutaneous fat ratio as an indicator of a ≥30% eGFR decline in chronic kidney disease

Whether the visceral-to-subcutaneous fat ratio (V/S ratio) is associated with renal prognosis in patients with chronic kidney disease (CKD) remains unclear. Furthermore, little is known about the effect of sex and the absolute amount of visceral fat accumulation such as visceral fat area (VFA) ≥100 cm² on the V/S ratio in relation to renal prognosis. In this study, 200 patients with CKD were evaluated for renal prognosis. Survival analyses and logistic regression analyses were conducted, generating time-series pseudo-R² values. The mean and percent change of the pseudo-R² values from the 6^th year to the 10^th year (6Y–10Y Mean and 6Y–10Y Change, respectively) were calculated for determining the cut-off points for the medium-term renal prognosis. Multivariate Cox regression analysis revealed that the V/S ratio was significantly associated with renal outcomes and that the VFA category (VFA ≥ 100 cm²) had significant interactions with the V/S ratio regarding renal prognosis. The hazard ratio (HR) of the V/S ratio was higher in the sub-cohort of VFA < 100 cm² than in the sub-cohort of VFA ≥ 100 cm² (HR: 6.42 vs. 1.00). Regarding sex differences, a strong association was noted between the V/S ratio and renal prognosis in women but not in men (HR: 2.40 vs. 1.10). On the other hand, 6Y–10Y Mean of the pseudo-R² values indicated differences in the cut-off points of the V/S ratio between men and women (V/S ratio: 0.75 vs. 0.5). Our findings indicate that it may be clinically meaningful to consider the differences in sex and the amount of VFA ≥100 cm² for the V/S ratio in relation to renal outcomes in patients with CKD. The 6Y–10Y Mean of the pseudo-R² values contributed to determining the cut-off points of the V/S ratio according to the sex difference.

Hemodialysis crossover study using a relative blood volume change-guided ultrafiltration control compared with standard hemodialysis: the BV-UFC study

Background

It has been difficult to sufficiently achieve body-fluid management using blood volume (BV) monitor during hemodialysis (HD) with constant ultrafiltration (UF) rate. Recently, a relative BV change-guided UF control (BV-UFC) system was developed by combining the concepts of an automatic feedback system that could control the UF rate and profile with real- time monitoring of relative changes in BV (%ΔBV). However, this system has limited application in the clinical setting. Therefore, in this study, we aimed to perform the crossover study on HD with BV-UFC compared to standard HD in terms of hemodynamic stability during HD.

Methods

Forty-eight patients entered an 8-week crossover period of standard HD or HD with BV-UFC. Prevalence of intradialytic hypotension (IDH) as a primary outcome and changes in blood pressure (BP), differences in %ΔBV, and achievement of the target ultrafiltration volume as secondary outcomes were compared. IDH was defined as a reduction in systolic BP ≥20 mmHg from the baseline value at 10 min after HD initiation.

Results

No significant differences were found in the prevalence of IDH, frequency of intervention for symptomatic IDH, and achievement of the target ultrafiltration volume between the groups. The %ΔBV was significantly fewer (-12.1 ± 4.8% vs. -14.4 ± 5.2%, p <0.001) in the HD with BV-UFC than that in the standard HD.

Conclusions

HD with BV-UFC did not reduce the prevalence of IDH compared with standard HD. The relief of a relative BV reduction at the end of HD may be beneficial in patients undergoing HD with BV-UFC.

Trial Registration

UMIN, UMIN000024670. Registered on December 1, 2016.

International variation in dialysis discontinuation in patients with advanced kidney disease

BACKGROUND

Decisions about dialysis for advanced kidney disease are often strongly shaped by sociocultural and system-level factors rather than the priorities and values of individual patients. We examined international variation in the uptake of conservative approaches to the care of patients with advanced kidney disease, in particular discontinuation of dialysis.

METHODS

We employed an observational cohort study design using data collected from patients maintained on long-term hemodialysis between 1996 and 2015 in facilities across 12 developed countries participating in the Dialysis Outcomes and Practice Patterns Study (DOPPS). The main outcome was discontinuation of dialysis therapy. We analyzed the association between several patient characteristics and time to dialysis discontinuation by country and phase of study entry.

RESULTS

A total of 259 343 DOPPS patients contributed data to the study, of whom 48 519 (18.7%) died during the study period. Of the decedents, 5808 (12.0%) discontinued dialysis before death. Rates of discontinuation were higher within the first few months after initiation of dialysis, among older adults, among those with a greater number of comorbidities and among those living in an institution. After adjustment for age, sex, dialysis duration, diabetes and dialysis era, rates of discontinuation were highest in Canada, the United States and Australia/New Zealand (33.8, 31.4 and 21.5 per 1000/yr, respectively) and lowest in Japan and Italy (< 0.1 per 1000/yr). Crude discontinuation rates were highest in dialysis facilities that were more likely to offer comprehensive conservative renal care to older adults.

INTERPRETATION

We found persistent international variation in average rates of dialysis discontinuation not explained by differences in patient case-mix. These differences may reflect physician-, facility- and society-level differences in clinical practice. There may be opportunities for international cross-collaboration to improve support for patients with end-stage renal disease who prefer a more conservative approach.

Association of erythropoietin resistance and fibroblast growth factor 23 in dialysis patients: Results from the Japanese Dialysis Outcomes and Practice Patterns Study

BACKGROUND

Fibroblast growth factor 23 (FGF23) plays an important role in chronic kidney disease (CKD)-related mineral and bone disorders. High FGF23 levels are associated with increased risk of anaemia in non-haemodialysis CKD patients. FGF23 also negatively regulates erythropoiesis in mice. We hypothesized that higher FGF23 levels are associated with increased erythropoietin hyporesponsiveness among haemodialysis patients.

METHODS

The study included 1044 patients from the Japanese Dialysis Outcomes and Practice Patterns Study (J-DOPPS) phase 5 (2012-2015). The outcome was erythropoiesis-stimulating agent hyporesponsiveness (ESA-hypo), defined as mean Hgb <10 g/dL and standardized mean ESA dose >6000 u/week over 4 months following FGF23 measurement. The association between ESA-hypo and FGF23 was estimated using multivariable-adjusted logistic generalized estimating equation regression models.

RESULTS

Patients with higher levels of FGF23 were younger and had higher levels of serum albumin, creatinine, albumin-corrected calcium, phosphorus, PTH, 25(OH)-vitamin D, and had higher percentages of intravenous (IV) iron, IV vitamin D and cinacalcet use. ESA-hypo was present in 144 patients (13.8%). Compared with the third quintile of FGF23 levels, the odds ratio (95% CI) of ESA-hypo was 2.14 (0.99, 4.62) and 1.74 (0.74, 4.11) for the first and fifth quintiles, respectively.

CONCLUSION

The lowest and highest levels of FGF23 were associated with higher odds of ESA-hypo in patients on maintenance haemodialysis, although the associations were not statistically significant. The relationship between FGF23 and anaemia, and particularly the increased risks of ESA-hypo at low FGF23 levels which might be the result of energy saving, must be confirmed in larger clinical studies.

Maximum Carotid Intima-Media Thickness in Association with Renal Outcomes

Aim: We aimed to examine the association between the maximum intima-media thickness of the carotid artery (Max IMT) and renal prognosis, considering their potential interaction with age.

Methods: Survival analyses were performed in 112 patients with chronic kidney disease (CKD), to assess renal prognosis, with the endpoint defined as a ≥ 30% decline in estimated glomerular filtration rate (eGFR) or end-stage renal disease.

Results: During a median follow-up of 12.5 years, 44 participants reached the study endpoint. The major determinant of Max IMT was the maximum IMT of the internal carotid artery (Max ICA-IMT), which was the distribution ratio of 50.0% of Max IMT. Kaplan–Meier analyses showed that Max IMT ≥ 1.5 mm was significantly associated with renal prognosis when age and eGFR were matched. On multivariate Cox regression analysis, Max IMT was significantly associated with the renal outcomes and had a significant interaction with the age categories (≥ 65 years or ＜65 years) ( P =0.0153 for interaction). A 1-mm increase in Max IMT was significantly associated with disease progression in the sub-cohort ＜65 years age-category, but not in the ≥ 65 years age-category; similarly the hazard ratio (HR) in the ＜65 years age-category was higher than in the ≥ 65 years age-category (HR: 2.52 vs. 0.95). Comparable results were obtained for Max ICA-IMT, Max bulb-IMT, but not for Max common carotid artery-IMT.

Conclusions: A higher Max IMT was a significant renal prognosis factor in patients with CKD aged ＜65 years. Our results may provide new insights into treating CKD.

COVID-19 of dialysis patients in Japan: Current status and guidance on preventive measures

In Japan, the first case of COVID‐19 in dialysis patients was reported on March 1, 2020. A total of 31 cases were reported by April 10, and it increased to 95 by May 15. Thereafter, with the rapid increase in the number of COVID‐19 cases in the general population since late March, there was a not surprising increase in the number of COVID‐19 cases in dialysis patients. The mortality rate is 16.2% (16/99 cases) in dialysis patients, which is higher than 5.3% (874/16 532 cases) in the general population. This higher mortality rate in dialysis patients with COVID‐19 might be related to their age; the majority of COVID‐19 cases are aged between 70 and 90 years old in dialysis patients, compared with between 20 and 60 years old in the general population. As COVID‐19 presents with severe symptoms and is associated with a high mortality rate in dialysis patients, dialysis patients who have contracted severe acute respiratory syndrome coronavirus 2 infection confirmed by polymerase chain reaction testing are required to be hospitalized under Japanese government policy. In cases of COVID‐19 hospitalizations, it is essential to prevent nosocomial infection. Therefore, patients must be sufficiently instructed in infection prevention and robust measures to prevent contraction and spread of the infection must be taken at dialysis facilities.

Biochemical evaluation of processed ascites in patients undergoing cell-free and concentrated ascites reinfusion therapy

The biochemical composition of processed ascites is not well researched and may differ among institutions. This prospective study was conducted to evaluate the biochemical characteristics of processed ascites of 11 patients with liver cirrhosis and carcinoma who underwent cell-free and concentrated ascites reinfusion therapy. The ascites due to carcinoma were more acidic and had higher lactate dehydrogenase activity than those due to liver cirrhosis. The ascites due to liver cirrhosis contained a higher amount of immunoglobulin than those due to carcinoma. Immunoglobulin preparations were approximately 2.95% IgG in liver cirrhosis ascites and 2.25% IgG in carcinoma ascites. Moreover, the concern about IgA infusion in the patient with IgA deficiency made it important to identify the source of the ascites. The present study provided fundamental information regarding the safety of cell-free and concentrated ascites reinfusion therapy.

High Serum Phosphate Level as a Risk Factor to Determine Renal Prognosis in Autosomal Dominant Polycystic Kidney Disease: A Retrospective Study

Background: Serum phosphate levels, which are associated with the progression of renal dysfunction in chronic kidney disease, in patients with autosomal dominant polycystic kidney disease (ADPKD) are lower than those in patients with other kidney diseases. However, their role in ADPKD remains unclear. This study aimed to determine whether serum phosphate levels could have an association with renal prognoses among patients with ADPKD. Methods: In total, 55 patients with PKD1 or PKD2 mutations but not undergoing dialysis were evaluated. Data regarding serum phosphate levels were collected, and Cox regression analyses were used to calculate hazard ratios (HRs) with renal replacement therapy as the endpoint. Results: The median (quartile 1; quartile 3) serum phosphate concentration was 3.4 (3.1; 3.9) mg/dL, and the estimated glomerular filtration rate (eGFR) was 39.5 (17.6; 65.7) mL/min/1.73 m². The multivariate analysis that included age, PKD1 mutation, eGFR, urinary protein excretion, hyperuricemia, and serum phosphate determined that eGFR (HR, 0.82; 95% confidence interval (CI), 0.74-0.90; p < 0.0001) and serum phosphate (HR, 6.78; 95% CI, 1.94-34.02; p = 0.0021) were independently associated with renal replacement therapy. Conclusions: We found that serum phosphate levels were significantly associated with poor renal prognoses in patients with ADPKD.

Annual dialysis data report 2017, JSDT Renal Data Registry

Abstract

The annual survey of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) was conducted for 4413 dialysis facilities at the end of 2017; among which 4360 facilities (98.8%) responded to the facility questionnaire, and 4188 (94.9%) responded to the patient questionnaire. The response rate of the 2017 survey was comparable with the past, even though it was the third year after the new anonymization method. The number of chronic dialysis patients in Japan continues to increase every year; it has reached 334,505 at the end of 2017. The mean age was 68.43 years. The prevalence rate was 2640 patients per million population. Diabetic nephropathy was the most common primary disease among the prevalent dialysis patients (39.0%), followed by chronic glomerulonephritis (27.8%) and nephrosclerosis (10.3%). The rate of diabetic nephropathy and nephrosclerosis has been increasing year by year, whereas that of chronic glomerulonephritis was declining. The number of incident dialysis patients during 2017 was 40,959; it has remained stable since 2008. The average age was 69.68 years and diabetic nephropathy (42.5%) was the most common cause in the incident dialysis patients. These patients caused by diabetes did not change in number for recent several years. Further, 32,532 patients died in 2017; the crude mortality rate was 9.8%. The patients treated by hemodiafiltration (HDF) have been increasing rapidly from the revision of medical reimbursement for HDF therapy in 2012. It has attained 95,140 patients at the end of 2017, which were 18,304 greater than that in 2016. The number of peritoneal dialysis (PD) patients was 9090 in 2017, which had been slightly decreasing since 2014. Further, 19.4% of PD patients treated in the combination of hemodialysis (HD) or HDF therapy (hybrid therapy). And 984 patients were treated by home HD therapy at the end of 2017; it increased by 49 from 2016.

Trial registration

JRDR was approved by the ethical committee of JSDT (approval number 1-3) and has been registered in “University hospital Medical Information Network (UMIN) Clinical Trials Registry” as a clinical trial ID of UMIN000018641 at 8th August 2015. https://upload.umin.ac.jp/cgi-bin/ctr/ctr_view_reg.cgi?recptno=R000021578 (Accessed 31 July 2019).

In vitro Evaluation of Solute Removal Characteristics in Intermittent Infusion Hemodiafiltration

BACKGROUND

In a typical hemodialysis (HD) session, excessive water removal sometimes induces peripheral circulatory failure and a rapid drop in blood pressure. Intermittent infusion hemodiafiltration (I-HDF), a new modality of dialysis therapy, has been developed to improve peripheral circulation by repeated intermittent infusion of dialysate during an HD session. In a typical I-HDF session, we infuse a volume of 200 mL of ultrapure dialysate by backfiltration at 150 mL/min every 30 min. The same volume is alternately removed from the patient's blood by filtration at a constant rate after each infusion. However, solute removal characteristics in I-HDF have not been clarified previously. We therefore conducted an in vitro study to investigate the characteristics of solute removal and the factors affecting such removal.

SUMMARY

We used human plasma to evaluate the effects of filtration (QF)/infusion (QI) flow rates on solute clearance (CL) and to estimate the time-averaged solute CL (TACL) values. The CL values for all solutes decreased with increasing QI. For small molecules such as urea, the CL values predominantly decreased with increasing QI because of decreasing diffusive transport. For medium and large solutes such as β2 microglobulin or larger, CL values predominantly increased with increasing QF because of increasing convective transport. However, the effects of these changes on TACL values were small compared with the CL value in a typical HD session because of the alternate filtration and infusion in I-HDF. Key Messages: Solute removal characteristics in I-HDF do not differ significantly from those in conventional HD treatment.

Long-term follow-up characteristics of patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) receiving chronic hemodialysis at a single center

BACKGROUND

The clinical characteristics and treatment of patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) after initiating chronic hemodialysis remain unknown.

METHODS

We retrospectively enrolled 11 adult patients with AAV receiving chronic hemodialysis in our hospital from 2000-2016. We collected data describing each patient's clinical findings and treatment before and after initiating hemodialysis. Patients with AAV with and without post-hemodialysis AAV relapse were compared statistically.

RESULTS

The average observation period was 6.8 ± 4.1 years, and the interval between diagnosis and initiating chronic hemodialysis was 1.9 ± 2.6 years. Before initiating chronic hemodialysis, five patients (45%) experienced 12 AAV relapses, with diagnoses made serologically or symptomatically. After initiating chronic hemodialysis, four patients experienced nine relapses, with no significant difference between the number of relapses and the number of patients experiencing relapse (p = 0.067 and 0.083, respectively). For patients' entire clinical courses before initiating chronic hemodialysis, the average steroid dose was 11.6 ± 6.9 g/y. Comparing before and after initiating chronic hemodialysis, the steroid dose decreased significantly to 3.3 ± 1.4 g/y after initiating chronic hemodialysis (p = 0.0012). Two of 11 patients died of serious infections after initiating chronic hemodialysis.

CONCLUSIONS

Our results showed that the number of relapses tended to be lower despite a significantly different lower amount of steroid after initiating hemodialysis compared with before initiating hemodialysis, and the burn-out phenomenon specific to uremic patients was inferred. We believe that early tapering of steroids should be considered to avoid death rather than focusing only on relapse.