The association of sleep duration with the risk of chronic kidney disease: a systematic review and meta-analysis.

Background and hypothesis: Published literature suggests that sleep duration and quality may be affected in adults with chronic kidney disease. However, the relationship between these two entities remains a matter of debate. The objective of this systematic review and meta-analysis is to assess the effect of sleep duration and quality on chronic kidney disease. Methods: A systematic review of the Medline/PubMed, Embase, Cochrane Library, and CINAHL databases was conducted for articles pertaining to the association between sleep duration and quality on chronic kidney disease. The main outcome was the hazard/risk ratio of chronic kidney disease in patients of varying sleep durations and quality. Results: In total, 42 studies (2 613 971 patients) with a mean age of 43.55 ± 14.01 years were included in the meta-analysis. Compared with a reference range of 7 to 8 hours of sleep, short sleep durations of ≤4 hours (RR 1.41, 95% CI: 1.16 to 1.71, P < 0.01), ≤5 hours (RR 1.46, 95% CI: 1.22 to 1.76, P < 0.01), ≤6 hours (RR 1.18, 95% CI: 1.09 to 1.29, P < 0.01), and ≤7 hours (RR 1.19, 95% CI: 1.12 to 1.28, P < 0.01) were significantly associated with an increased risk of incident chronic kidney disease. Long sleep durations of ≥8 hours (RR 1.15, 95% CI: 1.03 to 1.28, P < 0.01) and ≥9 hours (RR 1.46, 95% CI: 1.28 to 1.68, P < 0.01) were also significantly associated with an increased risk of incident chronic kidney disease. Meta-regression did not find any significant effect of age, gender, geographical region, and BMI and an association with sleep duration and risk of incident chronic kidney disease. Conclusion: Both short and long sleep durations were significantly associated with a higher risk of chronic kidney disease. Interventions targeted toward achieving an optimal duration of sleep may reduce the risk of incident chronic kidney disease.

Sodium-Glucose Cotransporter-2 Inhibitors Use in Patients with Reduced Kidney Function Hospitalized for Fluid Overload and Heart Failure: An Observational Study.

INTRODUCTION: Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are recommended in kidney disease and heart failure to reduce adverse clinical outcomes, but utilization can vary. To understand potential gaps in clinical practice and identify opportunities for improvement, we aimed to describe the prevalence and factors associated with SGLT2i prescription in patients with reduced kidney function hospitalized for fluid overload and/or heart failure. METHODS: Single-center observational study of patients with reduced kidney function (eGFR 20-59 mL/min/1.73 m2) hospitalized for fluid overload or heart failure between January 2022 and December 2023. Data were retrieved from electronic medical records. The outcome was SGLT2i prescription at discharge. Potential variables affecting SGLT2i prescription were identified during stakeholder engagement and evaluated using multivariable logistic regression. RESULTS: Among 2,543 patients, the median age was 79 (71, 86) years and admission eGFR was 38.7 (28.4, 49.4) mL/min/1.73 m2. SGLT2i was prescribed to 630 (24.8%) patients at discharge. SGLT2i prescription at discharge was independently associated with cardiovascular disease (OR 1.76, 95% CI: 1.31-2.35), diabetes (OR 1.59, 95% CI: 1.19-2.14), fluid overload or heart failure as the primary discharge diagnosis (OR 1.71, 95% CI: 1.29-2.28), SGLT2i pre-hospitalization (OR 104.91, 95% CI: 63.22-174.08), RAS blocker (OR 2.1, 95% CI: 1.65-2.89), and higher eGFR (OR 1.01, 95% CI: 1.003-1.02) at discharge; but inversely associated with older age (OR 0.97, 95% CI: 0.96-0.98). CONCLUSION: SGLT2i prescription at discharge was suboptimal among patients with reduced kidney function hospitalized for fluid overload and/or heart failure, especially in older age and more severe kidney disease. Additionally, cardiovascular disease, diabetes, primary discharge diagnosis of fluid overload or heart failure, prior SGLT2i use, and concurrent RAS blocker at discharge were independently associated with SGLT2i prescription at discharge. Interventions are needed to increase clinicians' knowledge and overcome clinical inertia to increase SGLT2i use in patients with fluid overload and heart failure.

Hospital Readmissions for Fluid Overload among Individuals with Diabetes and Diabetic Kidney Disease: Risk Factors and Multivariable Prediction Models.

AIMS: Hospital readmissions due to recurrent fluid overload in diabetes and diabetic kidney disease can be avoided with evidence-based interventions. We aimed to identify at-risk patients who can benefit from these interventions by developing risk prediction models for readmissions for fluid overload in people living with diabetes and diabetic kidney disease. METHODS: This was a single-center retrospective cohort study of 1,531 adults with diabetes and diabetic kidney disease hospitalized for fluid overload, congestive heart failure, pulmonary edema, and generalized edema between 2015 and 2017. The multivariable regression models for 30-day and 90-day readmission for fluid overload were compared with the LACE score for discrimination, calibration, sensitivity, specificity, and net reclassification index (NRI). RESULTS: Readmissions for fluid overload within 30 days and 90 days occurred in 8.6% and 17.2% of patients with diabetes, and 8.2% and 18.3% of patients with diabetic kidney disease, respectively. After adjusting for demographics, comorbidities, clinical parameters, and medications, a history of alcoholism (HR 3.85, 95% CI: 1.41-10.55) and prior hospitalization for fluid overload (HR 2.50, 95% CI: 1.26-4.96) were independently associated with 30-day readmission in patients with diabetic kidney disease, as well as in individuals with diabetes. Additionally, current smoking, absence of hypertension, and high-dose intravenous furosemide were also associated with 30-day readmission in individuals with diabetes. Prior hospitalization for fluid overload (HR 2.43, 95% CI: 1.50-3.94), cardiovascular disease (HR 1.44, 95% CI: 1.03-2.02), eGFR ≤45 mL/min/1.73 m2 (HR 1.39, 95% CI: 1.003-1.93) was independently associated with 90-day readmissions in individuals with diabetic kidney disease. Additionally, thiazide prescription at discharge reduced 90-day readmission in diabetic kidney disease, while the need for high-dose intravenous furosemide predicted 90-day readmission in diabetes. The clinical and clinico-psychological models for 90-day readmission in individuals with diabetes and diabetic kidney disease had better discrimination and calibration than the LACE score. The NRI for the clinico-psychosocial models to predict 30- and 90-day readmissions in diabetes was 22.4% and 28.9%, respectively. The NRI for the clinico-psychosocial models to predict 30- and 90-day readmissions in diabetic kidney disease was 5.6% and 38.9%, respectively. CONCLUSION: The risk models can potentially be used to identify patients at risk of readmission for fluid overload for evidence-based interventions, such as patient education or transitional care programs to reduce preventable hospitalizations.

Early repeat hospitalization for fluid overload in individuals with cardiovascular disease and risks: a retrospective cohort study.

AIMS: Fluid overload is a common manifestation of cardiovascular and kidney disease and a leading cause of hospitalizations. To identify patients at risk of recurrent severe fluid overload, we evaluated the incidence and risk factors associated with early repeat hospitalization for fluid overload among individuals with cardiovascular disease and risks. METHODS: Single-center retrospective cohort study of 3423 consecutive adults with an index hospitalization for fluid overload between January 2015 and December 2017 and had cardiovascular risks (older age, diabetes mellitus, hypertension, dyslipidemia, kidney disease, known cardiovascular disease), but excluded if lost to follow-up or eGFR < 15 ml/min/1.73 m2. The outcome was early repeat hospitalization for fluid overload within 30 days of discharge. RESULTS: The mean age was 73.9 ± 11.6 years and eGFR was 54.1 ± 24.6 ml/min/1.73 m2 at index hospitalization. Early repeat hospitalization for fluid overload occurred in 291 patients (8.5%). After adjusting for demographics, comorbidities, clinical parameters during index hospitalization and medications at discharge, cardiovascular disease (adjusted odds ratio, OR 1.66, 95% CI 1.27-2.17), prior hospitalization for fluid overload within 3 months (OR 2.52, 95% CI 1.17-5.44), prior hospitalization for any cause in within 6 months (OR 1.33, 95% CI 1.02-1.73) and intravenous furosemide use (OR 1.58, 95% CI 1.10-2.28) were associated with early repeat hospitalization for fluid overload. Higher systolic BP on admission (OR 0.992, 95% 0.986-0.998) and diuretic at discharge (OR 0.50, 95% CI 0.26-0.98) reduced early hospitalization for fluid overload. CONCLUSION: Patients at-risk of early repeat hospitalization for fluid overload may be identified using these risk factors for targeted interventions.

Exploration of patients' preference for modalities of care among peritoneal dialysis patients in Singapore: a single-center experience.

INTRODUCTION: Peritoneal dialysis (PD) is home-based dialysis therapy and therefore a suitable modality for kidney failure patients, particularly, during the COVID-19 pandemic. The present study examined patients' preferences for different PD-related services. METHODS: This was a cross-sectional survey study. Anonymized data from PD patients followed up at a single center in Singapore were collected using an online platform. The study focused on telehealth services, home visits, and monitoring of quality-of-life (QoL). RESULTS: A total of 78 PD patients responded to the survey. The majority of participants were Chinese (76%), married (73%), and between 45 and 65 years old (45%). The in-person visit was preferred over teleconsultation for consultation with nephrologists (68% versus 32%), counseling for kidney disease and dialysis by renal coordinators (59%), whereas the telehealth service was favored over in-person visit for dietary counseling (60%) and medication counseling (64%). Most participants (81%) preferred medication delivery over self-collection, and the acceptable turnaround time was 1 week. Sixty percent would like to have a regular home visit, but 23% refused such visits. The preferred frequency of home visits was one-to-three visits within the first 6 months (74%) and then 6 monthly for subsequent visits (40%). The majority of participants (87%) agreed with QoL monitoring, and the preferred frequency of monitoring varied between 6 monthly (45%) and yearly (40%). Participants also indicated three key areas in research to improve QoL, such as the development of artificial kidneys, portable PD devices, and simplification of PD procedure. Participants also would like to see improvement in two main areas of PD services, such as delivery service for PD solutions and social (instrumental, informational, and emotional) support. CONCLUSIONS: Most PD patients preferred in-person visits with nephrologists or renal coordinators; however, they favored telehealth services with dieticians and pharmacists. PD patients also welcomed home visit service and QoL monitoring. Future studies should confirm these findings.

A deep learning system for retinal vessel calibre improves cardiovascular risk prediction in Asians with chronic kidney disease.

Backgraund: Cardiovascular disease (CVD) and mortality is elevated in chronic kidney disease (CKD). Retinal vessel calibre in retinal photographs is associated with cardiovascular risk and automated measurements may aid CVD risk prediction. Methods: Retrospective cohort study of 860 Chinese, Malay and Indian participants aged 40-80 years with CKD [estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2] who attended the baseline visit (2004-2011) of the Singapore Epidemiology of Eye Diseases Study. Retinal vessel calibre measurements were obtained by a deep learning system (DLS). Incident CVD [non-fatal acute myocardial infarction (MI) and stroke, and death due to MI, stroke and other CVD] in those who were free of CVD at baseline was ascertained until 31 December 2019. Risk factors (established, kidney, and retinal features) were examined using Cox proportional hazards regression models. Model performance was assessed for discrimination, fit, and net reclassification improvement (NRI). Results: Incident CVD occurred in 289 (33.6%) over mean follow-up of 9.3 (4.3) years. After adjusting for established cardiovascular risk factors, eGFR [adjusted HR 0.98 (95% CI: 0.97-0.99)] and retinal arteriolar narrowing [adjusted HR 1.40 (95% CI: 1.17-1.68)], but not venular dilation, were independent predictors for CVD in CKD. The addition of eGFR and retinal features to established cardiovascular risk factors improved model discrimination with significantly better fit and better risk prediction according to the low (<15%), intermediate (15-29.9%), and high (30% or more) risk categories (NRI 5.8%), and with higher risk thresholds (NRI 12.7%). Conclusions: Retinal vessel calibre measurements by DLS were significantly associated with incident CVD independent of established CVD risk factors. Addition of kidney function and retinal vessel calibre parameters may improve CVD risk prediction among Asians with CKD.

Immune monitoring of prevalent kidney transplant recipients using Torque Teno Virus: Protocol for a single-centre prospective cohort study.

INTRODUCTION: Kidney transplant recipients (KTRs) suffer from immunosuppression-related adverse events (iRAEs), such as infections and malignancy from chronic immunosuppression, but are also at risk of graft loss from rejection with underimmunosuppression. Biomarkers that predict both iRAEs and rejection while allowing individualisation of immunosuppression exposure are lacking. Although plasma viral DNA levels of torque teno virus (TTV), a widely prevalent, non-pathogenic virus, have been shown to predict both iRAE and rejection in newly transplanted KTRs within the first year after transplant, its role for prevalent KTRs on stable immunosuppression is less clear.This study aims to determine the prognostic value of TTV levels for severe infections (defined as infections requiring hospitalisation) in prevalent KTRs on stable immunosuppression for at least 3 months and compare it against that of other commonly available biomarkers. The study also aims to explore the relationship between TTV levels and factors affecting the 'net state of immunosuppression' as well as other clinical outcomes. METHODS AND ANALYSIS: This is a single-centre, prospective, observational cohort study of 172 KTRs on stable immunosuppression for more than 3 months. TTV levels will be measured using the TTV R-GENE kit upon recruitment when study subjects are admitted and when kidney allograft biopsies are performed. Subjects will be monitored for iRAEs and rejection for at least 12 months. The relationship between TTV load and clinical outcomes such as severe infections will be analysed and compared against that from other common biomarkers and previously published predictive scores. ETHICS AND DISSEMINATION: The study was approved by the SingHealth Centralised Institutional Review Board (2023/2170). The results will be presented at conferences and submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05836636.

Efficacy and safety of low dose, weight-based subcutaneous enoxaparin protocol in recurrent arteriovenous access thrombosis.

BACKGROUND: This study aims to evaluate the safety and efficacy of a short-term, low dose, weight-based subcutaneous enoxaparin protocol (SEP) in maintaining the patency of arteriovenous (AV) access with recurrent thrombosis. METHODS: Prospective follow-up of 25 patients who presented to a tertiary institution with recurrent AV access thrombosis and treated with anticoagulation according to SEP following successful thrombectomy. Patency and safety outcomes of SEP were studied. RESULTS: The participants were 66.4 ± 10.2 years old and predominantly male (60%) and of Chinese ethnicity (72%). The AV accesses had a median age of 1.4 (0.6, 5.6) years with 60% being non-autogenous arteriovenous access while 40% were autogenous arteriovenous access. Thrombolytic agents (urokinase (72%) or alteplase (28%)) were used in all procedures while adjunct thrombectomy device was used in only four procedures. The mean dose of enoxaparin was 36.0 ± 8.2 mg or 0.64 ± 0.1 mg/kg/day for a mean duration 30.0 days (Interquartile range: 27.5, 31.0). One patient developed minor bleeding episode. Kaplan-Meier analysis demonstrated that the mean thrombosis-free survival pre- versus post-SEP adoption was 27.3 (95% CI 17.9-36.7) versus 183.5 (95% CI 100.1-266.9) days (p < 0.001). After adjusting for the type of thrombolytic agent, use of adjunct thrombectomy device, cutting balloon, drug-coated balloon, and stent graft, SEP remained a significant factor associated with longer thrombosis-free patency (HR 0.166: 95% CI 0.070-0.392, p < 0.001). DISCUSSION: SEP appears to be a feasible and safe thromboprophylaxis method to improve thrombosis-free patency for AV access with recurrent thrombosis.

Clinical features, management and outcomes of peritoneal dialysis patients during Delta and Omicron waves of COVID-19 infections.

INTRODUCTION: There were discrete outbreaks of SARS-CoV-2 infection in 2021 (Delta wave) and 2022 (Omicron wave) in Singapore, which affected patients receiving peritoneal dialysis (PD). METHODS: This study included all PD patients with COVID-19 infection from a single center between October 2021 and March 2022. The clinical presentation, management and outcomes of patients during the Delta and Omicron outbreaks were compared. RESULTS: A total of 44 PD patients developed SARS-CoV-2 infection (23 during the Delta wave and 21 during the Omicron wave): median age 66 (60.5-68.5) years, male (63.6%), Chinese ethnic (77.3%), diabetes mellitus (56.8%), and cardiovascular disease (45.5%). Approximately, 93.2% received two doses of the mRNA COVID-19 vaccine. Cough (81.8%) and fever (54.5%) were common presenting symptoms. Chest radiography showed ground glass opacity in 23.5% of patients, consolidation in 55.6%, and bilateral lung involvement in 33.3%. Eleven patients (25.6%) received antiviral therapy (Remdesivir), 7 (16.3%) received steroid, and 4 (9.3%) received monoclonal antibodies. Patients infected during the Delta wave were more likely to be hospitalized (73.9 vs 14.3%; p < 0.001) and receive antiviral therapy (39.1 vs 10.0%; p = 0.03) than those during the Omicron wave. The overall mortality rate was 11.4%, with significantly higher mortality during the Delta wave than during the Omicron wave (21.7 vs 0%; p = 0.03). CONCLUSIONS: The mortality rate was high among infected PD patients during Delta wave of COVID-19 infection. However, during the Omicron wave, most infected patients were treated in the community with favorable outcomes.

Impact of focal segmental glomerulosclerosis over the past decade.

OBJECTIVE: This is a study on the demographics and clinical outcomes including the response to therapy of patients with focal segmental glomerulosclerosis (FSGS) over the past decade. MATERIALS AND METHODS: All histologically proven FSGS cases diagnosed between 2008 and 2018 were analyzed for their clinical, laboratory, and histological characteristics including treatment that could influence the disease progression and renal outcome of these patients. We used the Columbia Classification for FSGS for the renal biopsy. RESULTS: There were two subgroups of FSGS patients; those with nephrotic syndrome and those without nephrotic syndrome. Patients with FSGS with non-nephrotic syndrome had poorer survival rates compared to the nephrotic group. For those without nephrotic syndrome, the indices responsible for progression involved more tubular and blood vessel lesions in addition to glomerular pathology compared to those with nephrotic syndrome. Patients with FSGS with nephrotic syndrome responded to immunosuppressants more favorably compared to the non-nephrotic group, though both groups responded with decreasing proteinuria. The nephrotic group had a better 10-year long-term survival rate of 92 vs. 72% for the non-nephrotic group (log-rank 0.002). The 10-year survival for the whole group of FSGS patients was 64%. CONCLUSION: Our data suggest that in FSGS, one of the significant components of the disease is the vascular and tubular damage, apart from the underlying glomerular pathology, resulting in varying responses to therapy, and the difference is reflected in inherently poorer response to immunosuppressant therapy in those without nephrotic syndrome as opposed to those with nephrotic syndrome, who responded to immunosuppressant therapy (IST) with stabilization of renal function and had less blood vessel and tubular lesions.

Development and validation of a novel nomogram to predict diabetic kidney disease in patients with type 2 diabetic mellitus and proteinuric kidney disease.

PURPOSE: Differentiating between diabetic kidney disease (DKD) and non-diabetic kidney disease (NDKD) in patients with Type 2 diabetes mellitus (T2DM) is important due to implications on treatment and prognosis. Clinical methods to accurately distinguish DKD from NDKD are lacking. We aimed to develop and validate a novel nomogram to predict DKD in patients with T2DM and proteinuric kidney disease to guide decision for kidney biopsy. METHODS: A hundred and two patients with Type 2 Diabetes Mellitus (T2DM) who underwent kidney biopsy from 1st January 2007 to 31st December 2016 were analysed. Univariate and multivariate analyses were performed to identify predictive variables and construct a nomogram. The discriminative ability of the nomogram was assessed by calculating the area under the receiver operating characteristic curve (AUROC), while calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test and calibration plot. Internal validation of the nomogram was assessed using bootstrap resampling. RESULTS: Duration of T2DM, HbA1c, absence of hematuria, presence of diabetic retinopathy and absence of positive systemic biomarkers were found to be independent predictors of DKD in multivariate analysis and were represented as a nomogram. The nomogram showed excellent discrimination, with a bootstrap-corrected C statistic of 0.886 (95% CI 0.815-0.956). Both the calibration curve and the Hosmer-Lemeshow goodness-of-fit test (p = 0.242) showed high degree of agreement between the prediction and actual outcome, with the bootstrap bias-corrected curve similarly indicating excellent calibration. CONCLUSIONS: A novel nomogram incorporating 5 clinical parameters is useful in predicting DKD in type 2 diabetes mellitus patients with proteinuric kidney disease.

Use of the helical SUPERA™ stent and Passeo-18 Lux™ drug-coated balloon to treat recurrent cephalic arch stenosis for dysfunctional brachiocephalic fistulas: 1 year results of the Arch V SUPERA-LUX study.

BACKGROUND: Aim of Arch V SUPERA-LUX was to evaluate the safety and efficacy of the combination therapy of SUPERA™ (Abbott Vascular, Santa Clara, CA, USA) helical stent implantation and Passeo-18 Lux™ (Biotronik Asia Pacific Pte Ltd, Singapore) drug coated balloon (DCB) elution to treat recurrent cephalic arch stenosis (CAS) in the setting of AV access dysfunction. METHODS: Investigator-initiated, single-center, single-arm prospective pilot study of 20 end-stage renal failure Asian patients with a dysfunctional brachiocephalic fistula. All had symptomatic recurrent CAS within 6 months of prior intervention. The lesion was pre-dilated with a standard high-pressure balloon (Biotronik Passeo-35 HP balloon). The DCB (Passeo-18 Lux™) is subsequently inflated and the SUPERA™ stent deployed to sit 2 mm distal to the cephalic arch and covering the CAS but within the DCB zone. All patients were prescribed dual antiplatelet therapy for 3 months and followed up with Duplex ultrasound at 6- and 12-months. RESULTS: There were 9 (45%) males and mean age was 67 ± 11.0 years. Mean time from prior procedure was 113 ± 68 days and main indication for reintervention was high venous pressure (9/20, 45%). Technical success was 100% and there were no peri-procedural complications related to either stent or DCB deployment. Target lesion primary patency at 6- and 12-months was 10/18 (55%) and 5/16 (31%), respectively. Mean time to target lesion re-intervention was 170 ± 82 days. Circuit access patency was 8/18 (44%) and 2/16 (13%) at 6- and 12-months respectively and mortality was 3/20 (15%) attributed to the patients' underlying co-morbidities. CONCLUSION: Dual prong strategy of using SUPERA™ stenting and Passeo-18 Lux™ drug elution for recurrent CAS, although safe, was no more efficacious than conventional balloon angioplasty or stenting alone. Development of an intense inflammatory reaction within the stent led to reinterventions of a number of cases with suboptimal results.

Intervention with selution SLR™ Agent Balloon for Endovascular Latent Limus therapy for failing AV Fistulas (ISABELLA) Trial: Protocol for a pilot clinical study and pre-clinical results.

BACKGROUND: The aim of this pilot clinical study is to evaluate the safety and efficacy of the Selution Sustained Limus Release (SLR)™ sirolimus-coated balloon (M.A. MedAlliance SA, Nyon, Switzerland) for improving the patency of failing arterio-venous fistulas (AVF) in hemodialysis patients. We also present herein a pre-clinical pharmacokinetic and safety evaluation of Selution™ to justify its first use in hemodialysis patients for endovascular access salvage. METHODS AND RESULTS: This is an investigator-initiated prospective single-center, non-blinded single-arm trial. Forty patients with clinically significant de novo or recurrent stenoses in a mature AVF circuit will be recruited. All stenotic lesions will be prepared with high pressure non-compliant conventional balloon angioplasty (CBA) prior to deployment of the Sustained-Release Selution™ sirolimus drug-eluting balloon. The primary efficacy endpoint is 6-month target lesion primary patency and the primary safety endpoint is freedom from localized or systemic serious adverse events through 30 days. Secondary endpoints of interest include technical and clinical success rates and circuit access patency at 3 and 6 months. Follow-up will occur for 2 years for those patients whose AVFs remain patent. Pharmacokinetic and histological animal safety studies performed with the Selution™ coating formulation showed prolonged arterial tissue retention of sirolimus with therapeutic levels up to 60 days and non-toxic and rapidly declining blood levels. Histological results in animal models demonstrated safety, freedom from intraluminal thrombus, reduction in restenosis by sirolimus elution compared to CBA, and no evidence of embolic phenomena indicative of adverse particulate effects. DISCUSSION: Long release sirolimus coated balloons may serve as a promising novel alternative therapy to paclitaxel-based technology for treating conduit stenosis secondary to neointimal hyperplasia. Pre-clinical pharmacokinetic and histological animal data are encouraging and provide suggestion of safety and efficacy in this setting. This single-center trial will provide a first step toward demonstration of efficacy and safety of this device for treatment of stenotic fistulas.

Endovascular salvage of failing arterio-venous fistulas utilising sirolimus eluting balloons: Six months results from the ISABELLA trial.

BACKGROUND: Aim of this pilot clinical study was to evaluate the safety and efficacy of the Selution Sustained Limus Release (SLR)™ sirolimus-eluting balloon (SEB) for improving failing arterio-venous fistulas (AVF) patency in Asian haemodialysis patients. METHODS: Prospective single-centre, multi-investigator, non-consecutive, non-blinded single arm trial. Forty end-stage renal failure Asian patients with a dysfunctional AVF underwent SEB angioplasty between May and November 2020. All stenotic lesions were prepared with high pressure non-compliant balloon angioplasty prior to SEB angioplasty. Endpoints of interest included target lesion primary patency and circuit access patency and safety through 30 days. All patients received dual antiplatelet therapy for 1 month and were followed up with Duplex ultrasound at 6 months. RESULTS: There was one subject dropout so final n = 39 patients (mean age 65.0 ± 11.9; males = 26 (66.7%)) and n = 43 target lesions treated. Main indication for intervention was dropping access flow (24/39; 61.5%) and most common target lesion was in the juxta-anastomosis (24/43; 54.5%). There was 100% technical and procedural success. There were no adverse events related to the SEB. Target lesion primary patency rates at 3 and 6 months were 39/41 (95.1%) and 28/39 (71.8%) respectively. Access circuit patency rates at 3 and 6 months were 35/37 (94.6%) and 22/35 (62.9%) respectively. There were 3 (7.7%) deaths all attributable to patients' underlying co-morbidities. CONCLUSIONS: Fistuloplasty using the novel Selution SLR™ SEB for dysfunctional AVF circuits seems a safe and effective modality in Asian haemodialysis patients at 6 months but larger randomised controlled studies are required now to determine its true efficacy against plain balloon angioplasty.

Ranger™ paclitaxel-coated balloon versus conventional balloon angioplasty for treatment of failing arteriovenous fistulas and grafts in haemodialysis patients: A retrospective cohort study.

BACKGROUND: Aim was to compare the safety and patency efficacy outcomes between Ranger™ paclitaxel-coated balloon (PCB)- versus conventional balloon angioplasty (POBA) in the treatment of haemodialysis access-related conduit stenosis. METHODS: Retrospective single-centre, multi-investigator, consecutive, double-arm comparative cohort study. About 130 end-stage renal failure Asian patients with dysfunctional arteriovenous fistula (AVF) or arteriovenous graft underwent PCB or POBA fistuloplasty between November 2018 and June 2020. All stenotic lesions were prepared with high pressure non-compliant balloon angioplasty prior to PCB angioplasty. All patients received at least one antiplatelet agent for 3 months duration post procedure. RESULTS: Mean age was 66.0 ± 10 years and 79/130 (61%) were males. PCB arm (n = 65) versus POBA arm (n = 65). Majority were AVFs circuits (122/130, 94%). Main indication for intervention was dropping access flow (98/130, 76%). About 172 lesions were treated (56% POBA, 44% PCB), and the juxta-anastomosis (JAS) was the main target lesion (87/172, 51%). There were no significant differences in safety outcomes (30-day adverse events, access thrombosis, abandoned AVF and death) between treatment groups. Mean time to target lesion reintervention (TLR) was longer in PCB-treated lesions (7.1 ± 2.7 vs 5.8 ± 3.2 months, p = 0.03), especially amongst recurrent lesions (7.3 ± 2.4 vs 5.7 ± 3.2, p = 0.02). Mean time to circuit reintervention was also longer in PCB-treated circuits (6.9 ± 2.8 vs 5.8 ± 3.7months, p = 0.04). There were 16 deaths (12%), all attributed to patient's underlying comorbidities. CONCLUSIONS: Fistuloplasty with Ranger™ PCB for failing arteriovenous circuits in end-stage renal failure patients, is a safe and efficacious modality compared to POBA in terms of longer freedom from TLR.

COVID-19 vaccination in peritoneal dialysis patients.

BACKGROUND: COVID-19 vaccine is recommended in Peritoneal dialysis (PD) patients, but a paucity of data is available regarding vaccine-related adverse effects among PD patients. METHOD: A cross-sectional study was conducted in a single center between October and November 2021. PD patients were provided with the online survey link to participate in the study. RESULTS: A total of 107 PD patients responded to the survey (55%: male, 79%: Chinese, 40%: > 65 years old). Of these, 95% received the COVID-19 vaccine (77% received two doses and 22% received three doses). Most participants (91%) received Pfizer vaccine. The main source of vaccine information was from the government (48%). The most common reason to receive and refuse vaccines were the perception of the seriousness of COVID-19 infection (63%) and concern about vaccine safety (60%), respectively. After the first dose, 25% of patients developed one or more vaccine-related adverse effects. Common local adverse effect was pain at the injection site (21%), and systemic adverse effects were muscle pain (15%), fatigue (13%). Similar adverse effects were observed with subsequent doses. None of them required hospitalization for vaccine-related adverse effects. Female patients had a higher risk of developing adverse effects than male patients after the first dose (odds ratio: 3.37; 95% confidence interval: 1.25 - 9.08). No such difference was observed in the subsequent dose. Age, race, employment status and history of drug allergy were not associated with the risk of adverse effects. CONCLUSIONS: The COVID-19 vaccine was well-tolerated by most PD patients, but few experienced non-severe adverse effects. All PD patients should be vaccinated against SAR-COV-2 infection.

Neutrophil gelatinase-associated lipocalin: a biochemical marker for acute kidney injury and long-term outcomes in patients presenting to the emergency department.

Introduction: Creatinine has limitations in identifying and predicting acute kidney injury (AKI). Our study examined the utility of neutrophil gelatinase-associated lipocalin (NGAL) in predicting AKI in patients presenting to the emergency department (ED), and in predicting the need for renal replacement therapy (RRT), occurrence of major adverse cardiac events (MACE) and all-cause mortality at three months post visit. Methods: This is a single-centre prospective cohort study conducted at Singapore General Hospital (SGH). Patients presenting to SGH ED from July 2011 to August 2012 were recruited. They were aged ≥21 years, with an estimated glomerular filtration rate <60 mL/min/1.73 m2, and had congestive cardiac failure, systemic inflammatory response syndrome or required hospital admission. AKI was diagnosed by researchers blinded to experimental measurements. Serum NGAL was measured as a point-of-care test. Results: A total of 784 patients were enrolled, of whom 107 (13.6%) had AKI. Mean serum NGAL levels were raised (P < 0.001) in patients with AKI (670.0 ± 431.9 ng/dL) compared with patients without AKI (490.3 ± 391.6 ng/dL). The sensitivity and specificity of NGAL levels >490 ng/dL for AKI were 59% (95% confidence interval [CI] 49%-68%) and 65% (95% CI 61%-68%), respectively. Need for RRT increased 21% per 100 ng/dL increase in NGAL (P < 0.001), whereas odds of death in three months increased 10% per 100 ng/dL increase in NGAL (P = 0.028). No clear relationship was observed between NGAL levels and MACE. Conclusion: Serum NGAL identifies AKI and predicts three-month mortality.

Regional citrate anticoagulation vs systemic heparin anticoagulation for double-filtration plasmapheresis.

INTRODUCTION: Double-filtration plasmapheresis (DFPP) has been utilized for immunomodulation in kidney transplantation. Anticoagulation is important to maintain circuit patency during DFPP. We aimed to compare the efficacy and safety of regional citrate anticoagulation (RCA) with systemic heparin anticoagulation during DFPP in kidney transplant recipients. METHODS: A retrospective cohort study was conducted to compare the efficacy and safety of RCA (RCA-DFPP) to systemic heparin anticoagulation (Hep-DFPP) for DFPP among kidney transplant recipients in a single tertiary center. RESULTS: A total of 112 sessions of DFPP were performed for 23 subjects, of which 62 sessions were RCA-DFPP and 50 sessions were Hep-DFPP. There were 13 sessions (11.6%) of premature circuit clotting, 10 sessions (16.1%) for RCA-DFPP and 3 sessions (6.0%) for Hep-DFPP (P = .10). All premature circuit clotting episodes occurred in subjects who underwent DFPP through a vascular catheter. Premature circuit clotting was associated with the use of a vascular catheter (odds ratio [OR] 14.2, 95% confidence interval [CI] 2.7-73.7; P < .01) and high postfilter ionized calcium (OR 12.7, 95% CI 1.4-112.5; P < .01). There was no major bleeding event. Hep-DFPP was associated with higher occurrence of hypocalcemia (OR 1.1, 95% CI 1.0-1.2; P < .01) and metabolic acidosis (OR 1.4, 95% CI 1.2-2.0; P = .04), while hypomagnesemia was more common for RCA-DFPP (OR 2.9, 95% CI 1.1-7.4; P = .03). CONCLUSION: Amongst kidney transplant patients who receive DFPP therapy, RCA-DFPP may be comparable to Hep-DFPP for the maintenance of circuit patency. Functioning vascular access is vital in avoiding premature clotting of the circuit. Close monitoring of electrolyte imbalances and coagulopathy related to DFPP is recommended.