Prevalent HD Patients Research Articles

Post Covid-19 Vaccination Immune Response in Hemodialysis Patient Compared to Normal Population

Abstract Background The COVID-19 pandemic has profound adverse effects on the population on dialysis. Patients requiring dialysis are at an increased risk of SARS-CoV-2 infection and mortality, and many have experienced psychological distress as well as delayed or suboptimal care. COVID-19 survivors have prolonged viral shedding, but generally develop a robust and long-lasting humoral immune response that correlates with initial disease severity. However, protection against reinfection is incomplete. Aim of the Work This study aimed to studying the immune response to COVID-19 Viruse vaccination in hemodialysis patients compared to the normal population Patients and Methods This study is a prospective case control study which include 40 prevalent HD patients received COVID-19 vaccination in haemodialysis units, Ain Shams University Hospitals. In comparison to 20 healthy control individuals who also received COVID-19 vaccination. Results Our study showed that there was no statistically significant difference between the studied groups as regard demographic data. Where the age ranges from 24-60 years old. There was 11 female and 29 males in our participant. Regarding occupation, there were 11 participants not working and 29 were working. In our study, there was a significant negative correlation between, SARS COVID IgG Au/ml & age per year, duration of hemodialysis per year, and parathyroid hormone. Whereas, there is a significant positive correlation between SARS COVID IgG Au/ml and kt/v % of renal hemodialysis dialysis patients. Otherwise, there is no significant relation between, SARS COVID IgG. In our study, there is a lower significant value of SARS COVID igG in renal dialysis patients compared to the control group regarding the history of COVID19 infection before vaccination and occurrence of post- vaccine adverse effects. Conclusion Hemodialysis patients demonstrate a hyporesponsiveness to vaccination against COVID-19. Although most patients on maintenance hemodialysis developed a substantial humoral response following the COVID vaccine, it was significantly lower than controls.

Nurse-assisted arterio-venous fistula cannulation during home hemodialysis: first results of the DIADIDEAL study

We have launched a pilot study, called DIADIDEAL, to propose nurse-assistance at home for arterio-venous fistula (AVF) cannulation in home hemodialysis (HHD) patients. The aim of the present study was to describe enrollment of the patients and their nurses. All prevalent HD patients on 30th November 2018 with no medical contraindication to HDD treatment and all incident patients on dialysis from the 30th November 2018 to the 21st April 2023 were eligible. Among 155 prevalent HD patients, 4 patients were included. Among the 276 incident patients on dialysis during the study period, 6 were included. We have phoned 23 nurse centers during the recruitment period. Eight of them agreed to learn in our unit how to cannulate AVF; 27 private nurses were enrolled. The results of the DIADIDEAL study will be available in 2024; we hope it will lead to a reimbursement of nurse-AVF cannulation at home in HDD.

Clinical Value of CASR Gene Polymorphism on Cinacalcet Response in Hemodialysis Patients with Secondary Hyperparathyroidism

Abstract Background Secondary hyperparathyroidism (SHPT) is a common complication of chronic kidney disease (CKD) patients on dialysis, associated with increased cardiovascular mortality and morbidity. Aim to evaluate frequency of variants of CaSR genes related to PTH regulation and to assess the effect of these single nucleotide polymorphisms on cinacalcet response among prevalent hemodialysis patients (HD) with SHPT. Patients and Methods This study included 50 prevalent HD patients with SHPT were recruited from Ain Shams University Hospitals' dialysis units. Clinical stable end-stage renal disease (ESDR) (35 males (70%) and 15 females (30%)), ≥ 18 years old on adequate HD for ≥ 6 months, with intact PTH (iPTH) ≥300 pg/ml and had been treated by cinacalcet. The patient was followed retrospectively for 6 months by measuring serum calcium, phosphorous, alkaline phosphatase, PTH to evaluate the response of cinacalcet. CASR gene and single nucleotide polymorphism (SNP) (rs1042636 and rs1802757) were measured by real-time PCR. Results CASR Gene/SNP rs1042636 (A/G), AA homozygous gene (wild gene) was present in n = 48 (96%) while AG heterozygous gene was present in n = 2 (4%). CASR Gene/SNP rs1802757(C/T), CC homozygous gene (wild gene) was present in n = 42 patients (84%) while CT heterozygous gene was present in n = 6 patients (12%). 21 patients (42%) responded to treatment of SHPT with reduction percent and 29 patients (58%) were non-responding to cinacalcet treatment for 6 months duration. The results showed no significant correlation between CASR gene polymorphism and response to treatment (p-value >0.05). Conclusion There is no statistically significant correlation between single nucleotide polymorphisms (SNPs) of the calcium sensing receptor gene (CASR) and response to cinacalcet as treatment of SHPT among HD patients, for further investigation studies.

Impact of Hemodialysis Time Prolongation on Blood Pressure Control

Abstract Introduction Hypertension prevalence among ESRD patients range from 76% to 90%. Sodium & volume overload is among the main mechanisms. Increasing the duration of dialysis time, either by longer session hours or increased sessions, aiming at reducing the dry weight to achieve euvolemia, may be beneficial for individuals who failed to achieve target BP or ideal volume status during standard HD prescription hours. We aim to study the effect of increasing hemodialysis session time on blood pressure control. Methods This observational study was conducted on 50 adult clinically stable hypertensive prevalent HD patients on thrice weekly maintenance HD. Patients with secondary causes of hypertension and Patients with decompensated medical conditions were excluded from our study. Patients were divided into 2 groups: (A) 25 patients who received longer session hemodialysis session (4.5 hour) and (B) 25 patients HD who received the usual 4 hours session. Revision of antihypertensive medications& dosages, dry weight was reassessed regularly, and they were instructed to restrict their salt intake as much as possible aiming at BP < 140/90 mmHg. they were followed up for a period of 6 months assess changes of pre-dialysis blood pressure to monitor response. Results Patients in both groups were age matched, with male sex predominance (64%in groupA&56% in groupB). Patients in both groups underwent their HD sessions mostly through AVF (68% and 92% for group A and B respectively). Ultrafiltration volume declined significantly with longer HD sessions compared to conventional sessions (pvalue <0.001 vs 0.523). Longer HD session time session was associated with highly significant decline in mean SBP, (p-value <0.001). Longer HD session time session was associated with highly statistically significant decline in mean DBP, (p-value <0.001). The decline in mean perdialysis SBP & DBP was -17.27 &-9 mmHg, respectively and the rate of decline of postdialysis SBP & DBP was -6.45 & -12.38 mmHg, respectively at 6th month compared to values in 1st month of follow up period. Conclusion Longer HD session duration is associated with better improvement in UF volume, mean SBP&DBP, pre-dialysis SBP&DBP and post-dialysis SBP&DBP as well.

#2779 THROMBOMODULIN IS A SPECIFIC MARKER OF ENDOTHELIAL DYSFUNCTION IN HEMODIALYSIS PATIENTS WITH NON-ALCOHOLIC FATTY LIVER DISEASE

Abstract Background and Aims Non-alcoholic fatty liver disease (NAFLD) is associated with endothelial dysfunction which is a common problem in hemodialysis patients and a risk for high cardiovascular mortality in hemodialysis. Thrombomodulin is a promising marker of endothelial cell injury in different pathological conditions. This study evaluates the additive effect of non-alcoholic fatty liver disease (NAFLD) in prevalent HD patients on endothelial dysfunction. Methods A case-control study was conducted on 60 end-stage renal disease (ESRD) patients on conventional hemodialysis: group A: 30 patients with NAFLD, group B: 30 patients without NAFLD, and control group of 30 apparently healthy subjects. Excluding elderly, diabetic patients, chronic Liver disease, advanced heart Failure, active infection, COVID-19 infection, autoimmune diseases and patients with hemodialysis catheters. Thrombomodulin was measured for all participants by ELISA technique. Results Thrombomodulin could detect endothelial dysfunction in patients with NAFLD at Cut off value <0.8 ng/ml with sensitivity 53.33%, specificity 80%, PPV 72.7%, and NPV 63.2%. On comparing Thrombomodulin in patients with NAFLD (4.378±3.762 ng/ml), Non-NAFLD (1.126±0.591 ng/ml), and control (0.755±0.314 ng/ml) there was a significant difference (P-value<0.001). Post hoc analysis showed significantly high Thrombomodulin levels in patients with {NAFLD versus Non-NAFLD} and {NAFLD versus control} with p-value<0.001, 0.001 respectively while there was no significant difference between patients with Non-NAFLD and control p-value 0.792. NAFLD patients with positive thrombomodulin have a risk of 2.5 times having endothelial dysfunction. There was no significant correlation between Thrombomodulin and all variables in the study. Conclusions Thrombomodulin can be used as specific marker for endothelial dysfunction in hemodialysis patients with Non Alcoholic fatty liver disease.

#5411 CARDIO-FISTULA RECIRCULATION REDUCTION IN OLDER ADULTS: IT'S NOT THAT EASY

Abstract Background and Aims Older adults are approximately 40% of all prevalent HD patients [ERA Annual report]. Cardiovascular disease is the leading cause of death in this cohort. It is well-known that the cardiotoxic effect of arterio-venous fistula (AVF) is fully realized when cardio-fistula recirculation (CFR) is above 20-30%. We believe that the reduction of AVF blood flow (Qa) in the elderly is often less effective than in the younger patients. Aim: to evaluate the outcomes of Qa reduction in the elder and the younger HD patients. Method The prospective cohort study included 21 patients over 60 years old and 36 patients under 60 years old: the median age was 74 years [IQR 69; 78, min-max 64-81] and 41 years [IQR 35; 45, min-max 31; 55], respectively. In all patients, GFR before reduction was more than 25%: 32.8% [IQR 29.2; 35.1, min-max 27.3; 38.9] and 33% [IQR 31; 35.125, min-max 27.1; 39.3], respectively. Qa reduction was performed by banding of the paraanastomotic AVF segment with intraoperative control (Doppler ultrasonography) until reaching Qa of 1.5 l / min or less. Results In all patients, we noted a significant (p<0.0001 in all cases) decrease in Qa as a result of the banding: in older adults from 2.1 l / min [IQR 1.9; 2.4, min-max 1.8; 2.8] to 1.2 l / min [IQR 1; 1.4, min-max 0.8; 1.5], delta Qa was -1 l / min [IQR -1.2; -0.9, min-max -1.5; -0.7], in younger patients from 2.8 l / min [IQR 2.5; 3.1, min-max 1.9; 3.5] to 1.3 l / min [IQR 1.1; 1.4, min-max 0.9; 1.5], -1.5 l / min [IQR -1.7; -1.3, min-max -2.3; -0.9], respectively. In both elder and younger patients, we noted a significant decrease in CFR - Fig. 1. However, after Qa reduction, only 5 of 21 elderly patients had CFR value less than 20%. Thus, 17 of 21 patients had CFR in the «gray zone» - 20-30%: 22.8% [IQR 21.85; 27.3, min-max 21; 29.2]. In younger patients, 25 of 36 had CFR less than 20% after Qa reduction, while 11 stayed in the «gray zone»: 21.15% [IQR 20.575; 22.3, min-max 20.3; 23.4]. The probability of reducing CFR to a safe level (less than 20%) after surgery was significantly less in the elder patients: RR = 0.3429 [95% CI 0.1495; 0.6852], p = 0.0011. We consider the lower baseline cardiac output in the elderly to be the main reason of the lower efficacy of Qa reduction: the difference between medians (older adults-younger patients before Qa reduction, Hodges-Lehmann method) was 1.9 l / min [95% CI 1.5; 2.4], p <0.0001. At the same time, Qa before reduction did not differ much between the older and the younger: 0.6 l / min [95% CI 0.4; 0.8], p <0.0001. Moreover, the reduction of Qa in elderly patients led to a decrease in the ejection fraction (EF), which was not noticed in young patients - Fig. 2. Notably, in all patients of both groups the initial value of the EF was more than 55%. We believe that this can be explained by an abrupt increase in afterload against the background of a decreased compensatory heart capability in the elderly. At the same time, decrease in the EF after Qa reduction in the elderly may indirectly indicate that conventional EF in the elderly is maintained by a presence of a high-flow AVF. Evaluation of EF against this background creates a putative picture of well-being and can mask the development of heart failure with reduced EF for a long time. Conclusion We noted a lower efficacy of Qa reduction as a method of reducing both cardio-fistula recirculation and cardiovascular risk in the elder patients compared to the younger patients on maintenance HD. Elder patients seem to require a different approach to reduce cardiovascular risk than younger patients.

FC099: Covid-19 and HD Vascular Access: Troubles are Coming

BACKGROUND AND AIMSPatients on HD are known to have many various adverse events associated with past COVID-19. In this cross-sectional study, we assessed the incidence of vascular access (VA) dysfunction (primary end point) and probability of successful reconstruction of preexisting permanent VA (AVF/AVG) in a case of its dysfunction (secondary end point) within two months after discharge from COVID hospital.METHODData were obtained from Moscow region COVID-19 register database. The study includes the results of treatment of 1386 HD patients who were admitted to hospital with suspected or confirmed COVID-19 between February 2020 and November 2021. All COVID-19 positive patients were hospitalized regardless of disease severity to prevent further spread of the infection in dialysis units. The main analysis included 934 patients with known sustainable VA: AVF (N = 804, 86.3%), AVG (N = 54, 5.8%) or CVC (N = 74, 7.9%). Median duration of HD was 34 (IQR 21–69) months (from 6 to 98).RESULTSHospital mortality among HD patients was 32.3%. The AVF/AVG/CVC ratio in recovered (N = 632) and deceased (N = 302) patients was 89.2%/5.7%/5% and 80.1%/6%/13.9%, respectively. HD via CVC was associated with an increased risk of death: RR = 1.877 (95% CI 1.472–2.302); P < 0.0001.Most of the recovered patients with AVFs (Figure 1, left) and AVGs (Figure 1, right) needed interventions due the VA dysfunction. Even if AVF patency was successfully restored, it led to the reduction of its functional segment. In contrast, most of the recovered patients with CVCs did not receive interventions for VA dysfunction (Figure 2).Thus, only 45.4% (287 of 632) of recovered patients did not receive interventions for VA dysfunction; the rest 54.6% showed dysfunction of VA. 23.6% (N = 149) underwent successful AVF/AVG reconstruction and retained function of the preexisting VA. In 15.3% (N = 97) patients, AVF/AVG function was completely lost and a new AVF/AVG was created. Conversion from functional AVF/AVG into CVC was performed in 14.1% (N = 89) patients. Thus, the incidence of complete loss of preexisting permanent VA function was 29.4% (N = 186).Conversion into better vascular access was performed in only 1.7% (N = 11) patients: conversion from AVG into AVF or from CVC into AVF/AVG.Among patients who underwent successful reconstruction of preexisting AVF, the probability of successful restore of its function within the first month was 55.3% (95% CI 48.3–62.2), during the second month—only 31.1% (95% CI 22.9–40.4). For AVG, the probability of maintaining of existing access during the first and second months was 23.8% (95% CI 9.3–45.2] and 18.2% (95% CI 3.2–48.3), respectively. Thus, reconstruction of permanent VA within the second month after discharge from COVID hospital increases the risk of complete loss of its function: RR = 1.469 (95% CI 1.22–1.762). Only 6.6% (N = 37) of patients received AVF/AVG reconstruction in COVID hospital.Compared with 2019, in 2021 the rate of reconstructive surgeries in the Moscow region decreased from 2.771 (95% CI 2.426–3.15) to 1.375 (95% CI 1.114–1.68) per 10 patient-years (only prevalent HD patients; P < 0.0001). The number of tertiary care centers for VA creation and maintaining in the region decreased from eight to five during the pandemic.At the same time, the rate of CVC implantations increased (outside of COVID hospitals) from 1.498 (95% CI 1.248–1.784) to 2.908 (95% CI 2.522–3.337) per 10 patient-years; P < 0.0001.CONCLUSIONCOVID-19 is associated with high incidence of VA dysfunction and complete loss of VA function. The delay in reconstruction of existing VA significantly increases the risk of its loss. This may be caused by a decrease in the number of reconstructive VA surgeries due to reducing the number of specialized centers and personnel. As a result, we observe an increase in CVC usage. Thus, over the next few years, we can expect increased prevalence of central vein stenoses and deterioration of treatment outcomes of HD patients.FIGURE 1:Need for intervention in recoveredafter COVID-19 HD patients with AVF (left) and AVG (right).FIGURE 2:Need for intervention in recovered patients with CVC.

MO793: AVF Blood Flow Reduction in the Older Adults

Abstract BACKGROUND AND AIMS Older adults are approximately 40% of all prevalent HD patients (ERA-EDTA Annual report, 2019). Cardiovascular disease is the leading cause of death in this cohort. It is well-known that the cardiotoxic effect of arterio-venous fistula (AVF) is fully realized when cardio-fistula recirculation (CFR) is above 20–30%. We believe that the reduction of AVF blood flow (Qa) in the elderly is often less effective than in younger patients. To evaluate the outcomes of Qa reduction in the elder and the younger HD patients. METHOD The prospective cohort study included 21 patients ˃ 60 years and 36 patients ˂60 years: the median age was 74 years [interquartile range (IQR) 69; 78, min-max 64–81] and 41 years (IQR 35; 45, min-max 31; 55), respectively. In all patients, glomerular filtration rate (GFR) before reduction was more than 25%: 32.8% (IQR 29.2; 35.1, min-max 27.3; 38.9) and 33% (IQR 31; 35.125, min-max 27.1; 39.3), respectively. Qa reduction was performed by banding of the para-anastomotic AVF segment with intraoperative control (Doppler ultrasonography) until reaching Qa of 1.5 L/min or less. RESULTS In all patients, we noted a significant (P &amp;lt; 0.0001 in all cases) decrease in Qa as a result of the banding: in older adults from 2.1 L/min (IQR 1.9; 2.4, min-max 1.8; 2.8) to 1.2 L/min (IQR 1; 1.4, min-max 0.8; 1.5), delta Qa was −1 L/min (IQR −1.2; −0.9, min-max −1.5; −0.7), in younger patients from 2.8 L/min (IQR 2.5; 3.1, min-max 1.9; 3.5) to 1.3 L/min (IQR 1.1; 1.4, min-max 0.9; 1.5), −1.5 L/min (IQR −1.7; −1.3, min-max −2.3; −0.9], respectively. In both elder and younger patients, we noted a significant decrease in CFR—Figure 1. However, after Qa reduction, only 5/21 elderly patients had CFR value less than 20%. Thus, 17/21 patients had CFR in the ‘gray zone’ —20–30%: 22.8% (IQR 21.85; 27.3, min-max 21; 29.2). In younger patients, 25/36 had CFR ˂ 20% after Qa reduction, while 11 stayed in the ‘gray zone’: 21.15% (IQR 20.575; 22.3, min-max 20.3; 23.4). The probability of reducing CFR to a safe level (˂ 20%) after surgery was significantly less in the elder patients: RR = 0.3429 [95% confidence interval (95%CI) 0.1495; 0.6852], P = 0.0011. We consider the lower baseline cardiac output in the elderly to be the main reason for the lower efficacy of Qa reduction: the difference between medians (older adults-younger patients before Qa reduction, Hodges–Lehmann method) was 1.9 L/min (95% CI 1.5; 2.4), P &amp;lt; 0.0001. At the same time, Qa before reduction did not differ much between the older and the younger: 0.6 L/min (95% CI 0.4; 0.8), P &amp;lt; 0.0001. Moreover, the reduction of Qa in elderly patients led to a decrease in the ejection fraction (EF), which was not noticed in young patients—Figure 2. Notably, in all patients of both groups, the initial value of the EF was more than 55%. We believe that this can be explained by an abrupt increase in afterload against the background of a decreased compensatory heart capability in the elderly. At the same time, a decrease in the EF after Qa reduction in the elderly may indirectly indicate that conventional EF in the elderly is maintained by a presence of a high-flow AVF. Evaluation of EF against this background creates a putative picture of well-being and can mask the development of heart failure with reduced EF for a long time. CONCLUSION We noted a lower efficacy of Qa reduction as a method of reducing both cardio-fistula recirculation and cardiovascular risk in the elder patients compared to the younger patients on maintenance HD. Elder patients seem to require a different approach to reduce cardiovascular risk than younger patients.

MO857: COVID-19 in Moscow Region Among HD Patients: Results of a Population Cross-Sectional Study

Abstract BACKGROUND AND AIMS We aimed to analyze the outcomes of HD patients with COVID-19 hospitalized in the Moscow region, Russia, and to compare it with those in the general population. METHOD Data were obtained retrospectively from the Moscow region COVID-19 register database, which comprises all hospitalizations with suspected or confirmed COVID-19 between February 2020 and November 2021. A total of 384 327 patients were included; 1 435 of them were ESRD patients. RESULTS Among ESRD patients there were 1386 HD patients and 49 kidney graft recipients. Thus, during the specified period, 48.5% of all prevalent HD patients of the Moscow region and only 7.8% of the graft recipients required hospitalization. Due to a few number of hospital admissions among kidney recipients they were excluded from the further analyses. We observed typical 4 waves of hospital admissions in the general population, but not in HD patients. In these patients, we noted a peak in December 2020 with a subsequent decrease in February, 2021; then the number of hospitalizations remained stable. The proportion of HD patients was approximately 0.5% of all patients with COVID-19 admitted to hospital. Almost all HD patients with COVID-19 were hospitalized regardless of disease severity. The mean age of hospitalized HD patients was significantly more than that in the general population: 68.95 ± 13.69 years versus 59.18 ± 17.11 years, P &amp;lt; 0.001. Of note, the mean age of HD patients in Russia is 56.3 ± 11.7 years. The proportion of men among hospitalized HD patients with COVID-19 reached 50.4% versus 43.5% in the general population. HD was associated with a significant increase in the risk of critical but stable and extremely critical (+ worsened: terminal and clinical death) condition at admission (Figure 1A): RR = 3.36 [95% confidence interval (95% CI) 3.12–3.59], P &amp;lt; 0.001 and RR = 4.83 (95% CI 3.93–5.92), P &amp;lt; 0.001, respectively. HD patients were significantly more likely to need for any kind of respiratory support (oxygen mask and mechanical ventilation (MV)) or MV alone (Figure 1B): RR = 1.72 (95% CI 1.63–1.81), P &amp;lt; 0.001 and RR = 4.67 (95% CI 4.18–5.21), P &amp;lt; 0.001, respectively. HD was associated with a significant increase in the risk of death (Figure 1C): RR = 3.48 (95% CI 3.24–3.72), P &amp;lt; 0.001. HD significantly increased the risk of death in patients without oxygen support and in patients with need for an oxygen mask (Figure 2A): RR = 3.56 (95% CI 2.97–4.25), P &amp;lt; 0.001 and RR = 2.47 (95% CI 2.18–2.78), P &amp;lt; 0.001, respectively. For patients requiring MV, mortality was &amp;gt;95% in both cohorts: RR = 0.999 (95% CI 0.955–1.01), P = 0.309. Deceased patients were older than survivors both in HD patients [73 (IQR 65–82) versus 69 (IQR 59–78) years; P &amp;lt; 0.001] and in the general population [72 (IQR 63–82) versus 60 (IQR 48–69) years; P &amp;lt; 0.001], however, the difference between medians was significantly greater in the general population: 13 (95% CI 12–14) versus 5 (95% CI 3–6) years. Heart and lung diseases increased the risk of death. In the general population concomitant heart diseases worsened the prognosis to a greater extent compared with lung diseases: RR = 2.69 (95% CI 2.64–2.74), P &amp;lt; 0.001 and RR = 1.3 (95% CI 1.26–1.35), P &amp;lt; 0.001, respectively. In HD patients pre-existing lung diseases had a greater impact on the risk of death than heart diseases: RR = 2.02 (95% CI 1.71–2.41), P &amp;lt; 0.001 and RR = 3.05 (95% CI 2.73–3.41), P &amp;lt; 0.001, respectively. In the multivariate model, significant predictors of death in HD patients were need for MV (OR = 9.81, 95% CI 8.48–17.8; P &amp;lt; 0.001) and lung diseases (OR = 2.92, 95% CI 1.92–5.42; P &amp;lt; 0.001], but not heart diseases, age and gender. CONCLUSION HD patients with COVID-19 have a significantly worse prognosis compared with the general population. The main risk factors for death are need for respiratory support and pre-existing lung diseases.

Effect of intradialytic exercise on the inflammatory markers in prevalent hemodialysis patients

Abstract Background Chronic low-grade inflammation is a feature of chronic kidney disease associated with increased risk of multiple morbidities and mortalities. Dialysis patients lead a sedentary life style which could add to this risk. Aim assessment of the effect of intradialytic exercise IDE on inflammatory markers in prevalent hemodialysis HD patients. Patients and Methods This longitudinal prospective study included 40 adult patients on regular HD, divided equally into 2 groups; Exercise Group (n = 20); received IDE 3 times/week for 3 months and Non-exercise Group (n = 20) matched in age and sex acting as controls. Patients were subjected to full history taking and clinical examination. Physical performance assessment using Short Physical Performance Battery tests (SPBT), Laboratory investigations included; Complete blood picture, C-reactive protein (CRP) and interleukin 6 (IL6) assessed using Enzyme linked immunosorbent assay. All assessments were repeated 3 months after regular IDE. Results At baseline, there was no difference between both groups regarding physical performance or inflammatory markers. After 3 months, SPBT was significantly increased in Exercise group (P &amp;lt; 0.001). Also, both serum CRP and IL-6 levels showed significant decrease in Exercise group compared to baseline (P &amp;lt; 0.001), while no similar change was noticed in non-exercise group. Conclusion The significant decrease in serum CRP and IL-6 levels after 3 months of regular IDE and the improvement in physical performance in exercise group implements that regular IDE exercise training program can improve physical function and inflammation in hemodialysis patients. Further studies on larger number of patients is warranted.

FC 093EFFICACY OF EXPANDED HEMODIALYSIS AT DIFFERENT DIALYSATE FLOWS

Abstract Background and Aims Expanded hemodialysis (HDx) is based on hollow fibre dialyzer focused on improving the clearance of middle molecules as a target for uremia treatment. According to in vitro and in vivo results, High cut off filters have high enough clearance to allow diminishing of dialysate flow. Our aim is to compare clearance of middle molecules at different dialysate flow (Qd) in HDx with TheranovaMR membranes. Our aim was to Evaluate efficacy of MCO dialyzer in terms of Kt/V and phosphorus levels at different prescribed dialysate flows (Qd) 400 vs 500 ml/min in HD patients from 10 renal clinics in Colombia. Method We performed a Prospective, observational, multicenter cohort study. Prevalent adult HD patients (&amp;gt;90 days), with weight lower or equal to 70 Kg, were included between September to November 2017 and prospectively followed for one year with routine monthly blood tests for HD adequacy and registered at both Qd groups at 1, 3, 6, 9 and 12 months. A mixed-model repeated measures analysis (MMRM) was performed to identify statistical differences over time. Socio-demographic and clinical characteristics of all patients were summarized descriptively by Qd. Results 462 patients were included: 127 with Qd 400 mL/min. We did not find statistically significative differences in serum levels of albumin, hemoglobin, calcium or phosphorus when comparing Qd 400ml/min vs 500 ml/min. We found statistically higher Kt/V in Qd 400 mL/min patients. (Table 2). In a sustainability analysis, part of Blue Planet dialysis research group, we calculated important savings in water waste in Qd 400 mL/min group. Conclusion MCO dialyzers are at least as effective in reaching HD adequacy parameters (Kt/V, PO4) at Qd 400 as 500 mL/min with interesting savings of potable water: 24 Liters were saved in each session per patient.

MO856IMPACT OF HEMODIALYSIS TIME PROLONGATION ON BLOOD PRESSURE CONTROL IN PREVALENT HEMODIALYSIS PATIENTS

Abstract Background and Aims Hypertension prevalence among ESRD patients range from 76% to 90%. Sodium &amp; volume overload is among the main mechanisms. Increasing theduration of dialysis time, either by longer session hours or increased sessions, aiming at reducing the dry weight to achieve euvolemia, may be beneficial for individuals who failed to achieve target BP or ideal volume status during standard HD prescription hours.We aim to study the effect of increasing hemodialysis session time on blood pressure control. Method This observational study was conducted on 50 adult clinically stable hypertensive prevalent HD patients on thrice weekly maintenance HD. Patients with secondary causes of hypertension and Patients with decompensated medical conditions were excluded from our study.Patients were divided into 2 groups:(A) 25 patients who received longer session hemodialysis session (4.5hour) and (B) 25 patients HD who received the usual 4 hours session. Revision of antihypertensive medications&amp;dosages,dry weight was reassessed regularly, andthey were instructed to restrict their salt intake as much as possible aiming at BP &amp;lt;140/90mmHg.they werefollowed up for a period of 6 months assess changes of pre-dialysis blood pressure to monitor response. Results Patients in both groups were age matched, with male sex predominance (64%in groupA&amp;56% in groupB). Patients in both groups underwent their HD sessions mostly through AVF (68% and 92% for group A and B respectively). Ultrafiltration volume declined significantly with longer HD sessions compared to conventional sessions (p-value &amp;lt;0.001 vs 0.523). Longer HD session time session was associated with highly significant decline in mean SBP, (p-value &amp;lt;0.001). Longer HD session time session was associated with highly statistically significant decline in mean DBP, (p-value &amp;lt;0.001). The decline in mean perdialysis SBP &amp; DBP was -17.27 &amp;-9 mmHg, respectively and the rate of decline of postdialysis SBP &amp; DBP was -6.45 &amp; -12.38 mmHg, respectively at 6th month compared to values in 1st month of follow up period. Conclusion Longer HD session duration is associated with better improvement in UF volume, mean SBP&amp;DBP, pre-dialysis SBP&amp;DBP and post-dialysis SBP&amp;DBP as well.

MO880EFFECTIVENESS OF MEDIUM CUT-OFF VS HIGH FLUX DIALYZERS: A PROPENSITY SCORE MATCHING COHORT STUDY

Abstract Background and Aims According to emerging evidence, medium cut-off membrane improves clearance of molecules larger than 25 kDa, including larger uremic toxins. There is growing evidence on clinical effectiveness outcomes associated with the use of these membranes. Our aim was to evaluate clinical effectiveness of medium cut-off (HDx) versus high flux (HF-HD) dialyzers in terms of hospitalization rate and duration, cardiovascular event rate and survival in a HD prevalent cohort in Colombia through an observational, multicenter retrospective cohort analysis. Method Adult Prevalent HD patients (&amp;gt; 90 days in HD) at Baxter Renal Care Services Colombia were included between September 1st, 2017 to November 30th, 2017 (follow-up until 2 years). Socio-demographic and clinical characteristics of all patients were summarized descriptively. Inverse probability of treatment weighting on the propensity score was used to balance comparison groups on indicators of baseline socio-demographic and clinical characteristics. Weighted incidence rate ratios (IRRs) and rates and duration of hospitalization and cardiovascular events according to dialyzer type were obtained using binomial negative regression with the weighting sample. Results We evaluated 1098 patients (37.7% women): 534 in HF-HD vs 564 in HDx (Table 1), median age was 60.6 years. Mean time on HD was 5.6 years (SD 5.51) for HF-HD and 5.88 for HDX (SD 5.48) We observed lower hospitalization rates in HDx group, (IRR HDx/HF-HD: 0.82 95% CI 0.69 to 0.98; p=0.03); and cardiovascular events rate, (IRR HDx/HF-HD: 0.65 95% CI 0.47 to 0.91; p=0.01) see Table 2. Main cause of hospitalization was cardio-cerebrovascular (Table 3). We observed no differences in hospitalization duration or survival. Conclusion We evaluated 1098 patients (37.7% women): 534 in HF-HD vs 564 in HDx (Table 1), median age was 60.6 years. Mean time on HD was 5.6 years (SD 5.51) for HF-HD and 5.88 for HDX (SD 5.48) We observed lower hospitalization rates in HDx group, (IRR HDx/HF-HD: 0.82 95% CI 0.69 to 0.98; p=0.03); and cardiovascular events rate, (IRR HDx/HF-HD: 0.65 95% CI 0.47 to 0.91; p=0.01) see Table 2. Main cause of hospitalization was cardio-cerebrovascular (Table 3). We observed no differences in hospitalization duration or survival.

MO599COMPARISON OF TOTAL BODY WATER MEASURED BY BIOIMPEDANCE SPECTROSCOPY TO UREA DISTRIBUTION VOLUME ESTIMATED FROM UREA KINETIC MODELING IN HEMODIALYSIS PATIENTS

Abstract Background and Aims Monitoring of fluid, body composition and nutritional changes is important in clinical nephrology. The Body Composition Monitor (BCM; Fresenius Medical Care, Bad Homburg, Germany) measures whole-body bioimpedance and determines extracellular and intracellular resistance by using the Cole-model to estimate total body water (TBW-BCM) and its partition into extracellular and intracellular water. Both can then be used to define body composition and separate body weight into lean tissue mass, adipose tissue mass, and fluid overload. Urea kinetic modeling (UKM) allows the estimation of dialysis dose (double-pooled Kt/V), urea distribution volume (V-UKM) and dietary protein intake. We studied the bias between estimated V-UKM to anthropometric and measured TBW-BCM (Vant, TBW-BCM). Method Pre-hemodialysis (HD), electrodes for the BCM assessments were placed on the non-arteriovenous access arm and ipsilateral leg, respectively, with the patient in a supine position. Vant was calculated using the Watson equation. In addition to these assessments we entered the specified values from the most recent urea kinetic modeling (UKM) treatment into the online solute-solver calculator (http://ureakinetics.org). We chose a baseline ratio of modeled/anthropometric volume of 0.6 to 1.3 L to exclude values with data entry errors and/or UKM sampling errors. We calculated the post HD TBW-BCM by subtracting the intradialytic weight loss and adjusted these estimates by the differences in post HD weight between sessions to make both estimates comparable. We depicted the comparison between the estimated V-UKM versus the TBW-BCM in a scatter- and Bland-Altman (BA) plot (Figure). For the purpose of error investigation we studied the computed bias (V-UKM minus TBW-BCM) as a function of body mass index (BMI) and stray capacitance (td) in a BA plot. We then calculated the difference between Vant and V-UKM and illustrated the comparison in a scatter and BA plot. Results In a cross-sectional design, we studied 161 stable prevalent HD patients (61.3±14.7 years, 98 (60.9%) males, height of 167.5±10.7 cm) prior to their treatment. The regression plot showed slight agreement (R2= 0.69) and the Bland-Altman plot no systematic trends or proportional error in the main analysis (Figure 1a and b). Neither BMI or td explained bias and variance in the bias between both estimates. Vant and V-UKM plots showed agreement (R2 of 0.68) with a mean bias of -2.3±5.1 and no proportional error. Conclusion Both TBW-BCM and the V-UKM as the “bronze standard” of TBW estimation seemed to agree reasonably well. Neither body composition measurement or kinetic modeling approach showed any significant influence on the accuracy and precision of the estimate. According to BCM availability, estimated V-UKM or measured TBW-BCM could be used alternatively in practice to support clinical decision when pharmacokinetic considerations are concerned.

Impact of Hemodialysis Time Prolongation on Blood Pressure Control

Introduction: Hypertension prevalence among end-stage renal disease (ESRD) patients range from 76% to 90%. Increasing the duration of dialysis time, either by longer session hours or increased sessions, aiming at reducing the dry weight to achieve euvolemia, may be beneficial for individuals who failed to achieve target BP or ideal volume status during standard HD prescription hours. Objective: We aimed to study the effect of increasing hemodialysis session time on blood pressure control. Methods: This observational study was conducted on 50 hypertensive prevalent HD patients on thrice-weekly maintenance HD. Patients were divided into 2 groups: (A) 25 patients who received longer hemodialysis session (4.5 hours) and (B) 25 patients HD who received the usual 4 hours session. They were followed up for a period of 6 months to assess changes of pre-dialysis blood pressure to monitor response. Results: Ultrafiltration volume declined significantly with longer HD sessions compared to conventional sessions (p-value < 0.001 versus 0.523). Longer HD session time group was associated with highly significant decline in mean SBP, (p-value < 0.001). Moreover, longer HD session time group was associated with highly statistically significant decline in mean DBP, (p-value < 0.001). The decline in mean perdialysis SBP & DBP was -17.27 & -9 mmHg respectively and the rate of decline of postdialysis SBP & DBP was -6.45 & -12.38 mmHg respectively at 6th month compared to values in 1st month of follow up period. Conclusion: Longer HD session duration is associated with better improvement in UF volume, mean SBP & DBP, pre-dialysis SBP & DBP and post-dialysis SBP & DBP as well.

Proton pump inhibitor use and its relation to serum magnesium levels among hemodialysis patients: A single centre study in a South Indian tertiary care hospital

Introduction: Proton pump inhibitors (PPI) are commonly used in clinical practice for various indications such as gastritis, peptic ulcer and gastroesophageal reflux disease. In Observational studies, Hypomagnesaemia has been associated with PPI use in general population. Hypomagnesaemia is a significant predictor of mortality especially in HD patients. There is a lack of data regarding association of PPI with hypomagnesemia in dialysis population. Materials and Method: Study was conducted in Tertiary care hospital using a pre dialysis serum samples by colorimetric-kit method. Mean of two consecutive serum Mg levels measured at 6 weeks interval was calculated for further analysis. Clinical, demographic data along with duration of PPI use in months were recorded. Patients on diuretics, chronic diarrhoea and HD for Acute Kidney Injury were excluded. Student t-test was used for comparison between PPI users and non users.single-centre observational design on 87 prevalent HD patients on twice weekly and thrice weekly maintenance HD with regular PPI use for >2 weeks. Serum Magnesium (Mg) level was determined using Results:55 patients were on Proton Pump Inhibitors at the time of study. All patients were dialyzed with dialysate Mg of 1.2mg/dL (0.7 mmol/L). Average duration of PPIs use was 6 months (6± 1.45 months). Serum Mg levels among PPI users was 2.5 mg/dL and non-users was 2.4 mg/dL. No correlation was found between serum Mg levels and duration of PPIs use (p > 0.8). Conclusion: In our study we did not find any association between hypomagnesemia and PPI use in hemodialysis patients. As our study was single centered, small population with short follow up, further well defined long term Randomized controlled trials on Mg levels with PPI use are needed. Keywords:Hypomagnesemia, Proton pump inhibitor, Chronic kidney disease, Hemodialysis

Barriers to Home Hemodialysis Across Saskatchewan, Canada: A Cross-Sectional Survey of In-Center Dialysis Patients.

Background:Despite clinical and lifestyle advantages of home hemodialysis (HHD) compared with in-center hemodialysis (ICHD), it remains underutilized in our province. The aim of the study was to explore the patients’ perception and to identify the barriers to use of HHD in Saskatchewan, Canada.Objectives:The primary objective of the study was to evaluate and explore patient perceptions of HHD and to identify the obstacles for adoption of HHD in Saskatchewan. The secondary objective was to examine variations in the patients’ perceptions and barriers to HHD by center (main dialysis units vs satellite dialysis units).Design:This is a cross-sectional observational survey study.Setting:Two major centers (Regina and Saskatoon) and 5 associated satellite units attached to each center across the province of Saskatchewan.Patients:We approached all prevalent ICHD patients across Saskatchewan, 398 agreed to participate in the study.Measurements:Self-reported barriers to HHD were assessed using a questionnaire.Methods:A questionnaire was designed to determine the patients’ perceived barriers to HHD. Descriptive statistics was used to present the data. Chi-square and Mann-Whitney U test were used to compare the patients’ responses between main and satellite unitsResults:Satisfaction with current dialysis care (91%), increase in utility bills (65%), fear of catastrophic events at home (59%), medicalization of one’s home (54%), and knowledge deficits toward treatment modalities (54%) were the main barriers to HHD uptake. Compared with patients dialyzing in our main units, satellite patients chose not to pursue HHD more frequently because they had greater satisfaction with their current dialysis unit care (97% vs 87%, P < .001), felt more comfortable dialyzing under the supervision of medical staff (95% vs 86%, P < .007), could not afford additional utility costs (92% vs 45%, P < .001), were unaware of the risks and benefits of HHD (83% vs 33%, P < .001), had concerns over time commitments for training to HHD (69% vs 32%, P < .001), and had concern for family burnout (60.8% vs 40.6%, P < .001).Limitations:We used questionnaires to quantify known barriers, and this prevents inclusion of additional barriers that individual patients may consider important. Cross-sectional data can only be used as a snapshot. Only 398 patients agreed to participate, and the results cannot be generalized to 740 prevalent HD patients. We did not capture data on demographics (age, income, and literacy level), comorbidities, and dialysis vintage, which would have been helpful in interpretation of the results.Conclusions:Satisfaction with in-center care, lack of awareness and education, specifically in the satellite population, concerns with family burnout, expenses associated with utilities, and training time will need to be addressed to increase the uptake of HHD.Trial Registration:The study was not registered on a publicly accessible registry as it did not involve any health care intervention on human participants.

Dual Roles of the Mineral Metabolism Disorders Biomarkers in Prevalent Hemodilysis Patients: In Renal Bone Disease and in Vascular Calcification.

SummaryBackgroundVascular calcification (VC) is highly prevalent in dialysis (HD) patients, and its mechanism is multifactorial. Most likely that systemic or local inhibitory factor is overwhelmed by promoters of VC in these patients. VC increased arterial stiffness, and left ventricular hypertrophy. Thus, the present study aimed to investigate the association of VC and myocardial remodeling and to analyze their relationship with VC promoters (fibroblast growth factor 23-FGF23, Klotho, intact parathormon-iPTH, vitamin D) in 56 prevalent HD patients (median values: age 54 yrs, HD vintage 82 months).MethodsBesides routine laboratory analyzes, serum levels of FGF 23, soluble Klotho, iPTH, 1,25-dihydroxyvitamin D3; pulse wave velocity (PWV); left ventricular (LV) mass by ultrasound; and VCs score by Adragao method were measured.ResultsVC was found in 60% and LV concentric or eccentric hypertrophy in 50% patients. Dialysis vintage (OR 1.025, 95%CI 1.007–1.044, p=0.006) FGF23 (OR 1.006, 95% CI 0.992–1.012, p=0.029) and serum magnesium (OR 0.000, 95%CI 0.000–0.214, p=0.04) were associated with VC. Changes in myocardial geometry was associated with male sex (beta=-0.273, 95% CI -23.967 1.513, p=0.027), iPTH (beta 0.029, 95%CI -0.059–0.001, p=0.027) and vitamin D treatment (beta 25.49, 95%CI 11.325–39.667, p=0.001). Also, patients with the more widespread VC had the highest LV remodeling categories. PWV was associated patient’s age, cholesterol, diastolic blood pressure, LV mass (positively) and serum calcium (negatively), indicating potential link with atherosclerotic risk.ConclusionsDespite to different risk factors for VC and myocardial remodeling, obtained results could indicate that risk factors intertwine in long-term treatment of HD patients and therefore careful and continuous correction of mineral metabolism disorders is undoubtedly of the utmost importance.

Soluble Toll-like Receptor 4: A New Player in Subclinical Inflammation and Malnutrition in Hemodialysis Patients

Toll-like receptor 4 (TLR4) promotes inflammation in hemodialysis patients (HD). A soluble form of extracellular TLR4 (sTLR4) has been recently characterized, which showed the ability to attenuate TLR4 signalling. In this study, we describe the sTLR4 profile in regular HD patients. In a cross-sectional study we enrolled forty prevalent HD patients (68.2 ± 16.3 years, twenty-five males) with a median dialysis vintage of 41 months. Nineteen patients were undergoing standard bicarbonate HD (BHD) and 21 patients on-line hemodiafiltration (HDF). Ten healthy sex-matched subjects constituted the controls (C). Before and after the HD session, serum was tested for sTLR4 levels by ELISA. Moreover, clinical and biochemical datawere collected, including body mass index, albumin, and C-reactive protein (CRP) levels. Body composition was expressed as a 3-compartment model, providing lean tissue index and fat tissue index (FTI). Describe the profile of sTLR4 in HD patients, evaluating the correlations among sTLR4 levels and the main clinical characteristics, inflammatory and nutritional parameters. Patients with subclinical inflammation (i.e., high CRP levels without clinical symptomatology) presented higher sTLR4 levels (0.42±0.25ng/mL) with respect to both C and not inflamed HD patients (0.23±0.19ng/mL, P<.05). There was a significant direct correlation between predialysis sTLR4 and body mass index, FTI (r=0.55), and CRP levels (r=0.52) and inverse correlation with lean tissue index and albumin (r=-0.4). In multivariate analysis, sTLR4 resulted directly associated with FTI (P=.038). Notably, sTLR4 levels resulted higher in bicarbonate hemodialysis versus hemodiafiltration (0.37±0.18 vs. 0.19±0.21ng/mL, P<.05). sTLR4 correlates with inflammatory and nutritional parameters, presenting as a new potential player in modulating subclinical inflammation in HD patients.

Volume Estimates in Chronic Hemodialysis Patients by the Watson Equation and Bioimpedance Spectroscopy and the Impact on the Kt/Vurea calculation.

Background:Accurate assessment of total body water (TBW) is essential for the evaluation of dialysis adequacy (Kt/Vurea). The Watson formula, which is recommended for the calculation of TBW, was derived in healthy volunteers thereby leading to potentially inaccurate TBW estimates in maintenance hemodialysis recipients. Bioimpedance spectroscopy (BIS) may be a robust alternative for the measurement of TBW in hemodialysis recipients.Objectives:The primary objective of this study was to evaluate the accuracy of Watson formula–derived TBW estimates as compared with TBW measured with BIS. Second, we aimed to identify the anthropometric characteristics that are most likely to generate inaccuracy when using the Watson formula to calculate TBW. Finally, we derived novel anthropometric equations for the more accurate estimation of TBW.Design and Setting:This was a cross-sectional study of prevalent in-center HD patients at St Michael’s Hospital.Patients:One hundred eighty-four hemodialysis patients (109 men and 75 women) were evaluated in this study.Measurements:Anthropometric measurements including weight, height, waist circumference, midarm circumference, and 4-site skinfold (biceps, triceps, subscapular, and suprailiac) thickness were measured; fat mass was measured using the formula by Durnin and Womersley. We measured TBW by BIS using the Body Composition Monitor (Fresenius Medical Care, Bad Homburg, Germany).Methods:We used the Bland-Altman method to calculate the difference between the TBW derived from the Watson method and the BIS. To derive new equations for TBW estimation, Pearson’s correlation coefficients between BIS-TBW (the reference test) and other variables were examined. We used the least squares regression analysis to develop parsimonious equations to predict TBW.Results:TBW values based on the Watson method had a high correlation with BIS-TBW (correlation coefficients = 0.87 and P < .001). Despite the high correlation, the Watson formula overestimated TBW by 5.1 (4.5-5.8) liters and 3.8 (3.0-4.5) liters, in men and women, respectively. Higher fat mass and waist circumference (general and abdominal obesity) were correlated with the greater TBW overestimation by the Watson formula. We created separate equations for men and women based on weight and waist circumference.Limitations:The main limitation of our study was the lack of an external validation for our novel estimating equation. Furthermore, though BIS has been validated against traditional reference standards, our assumption that it represents the “gold standard” for body compartment assessment may be flawed.Conclusions:The Watson formula generally overestimates TBW in chronic dialysis recipients, particularly in patients with the highest waist circumference. Widespread reliance on the Watson formula for derivation of TBW may lead to the underestimation of Kt/Vurea..