Chronic Hemodialysis Patients Research Articles

#3101 LOW CIRCULATING LEVELS OF CARDIO-REGULATORY MIRNAS PREDICT WORSE OUTCOMES IN HEMODIALYSIS PATIENTS

Abstract Background and Aims Patients with end stage renal disease (ESKD) on hemodialysis (HD) have a high risk of cardiovascular (CV) events, this being mostly related to the presence of uraemic cardiomyopathy. A deregulation in the expression of various microRNAs (miRNAs: non-coding RNAs that regulate post-transcriptional gene expression) has previously been implied in pathological cardiac remodelling. Nevertheless, scarce evidence has accrued so far on a possible significance in CV morbidity and mortality in HD patients, in relationship with the presence of uremic cardiomyopathy. Method We run a pilot, prospective, multicentre cohort study involving 74 ESKD patients undergoing chronic HD from 3 different hospitals in Italy and Greece. HD patients underwent a thorough clinical, laboratory and echocardiography assessment and were then prospectively followed for 24 months or until the occurrence of a composite endpoint of (CV and all-cause) mortality or non-fatal CV events. Through a systematic review of the literature, we identified a small panel of miRNAs (30a-5p, 23a-3p,451a and let7d-5p), which levels are known to be altered in either major CV disorders and kidney failure. miRNAs were then measured in the blood of HD patients and in a small group of matched healthy controls. Results miRNAs 23a-3p (p<0.0001), 451a (p = 0.001), 30a-5p (p = 0.003) and let7d-5p (p <0.0001) were all reduced in HD patients as compared with controls. Significant correlations were found between miRNAs and indexes of cardiac dysfunction such as Vmax, TAPSE and E/E’, as well as with some other laboratory parameters such as uric acid, sodium, potassium, HDL and CRP. During follow-up, 30/74 patients (40.5%) reached the composite endpoint. In these individuals, all miRNAs but let7d-5p were significantly reduced at baseline (p<0.0001). As showed by multivariate Cox-regression analyses, miRNAs 23a-3p, 451a, 30a-5p were all predictors of the composite endpoint (HR ranging from 0.943 to 0.995; p = 0.05 to 0.02) and Kaplan-Meier analyses confirmed a faster progression to the endpoint in subjects with miRNAs levels below an optimal ROC-derived cut-off value (p ranging from 0.001 to <0.0001; crude HRs 7.95 to 8.61; Figure 1). Conclusion Our study demonstrated that the evaluation of a very small panel of circulating miRNAs (30-5p, 23a–3p and 451a) may impart important prognostic information in chronic HD patients with respect to mortality and CV risk. Although the biological meaning of their deregulation remains unanswered, these preliminary findings may set the stage for larger investigation to generalize their usefulness as biomarkers, as well as possible therapeutic targets.

#4877 THE EFFECT OF NURSE-LED 8-ZONE LUNG ULTRASOUND GUIDED TITRATION OF DRY WEIGHT ON HYPERTENSION IN APPARENTLY EUVOLAEMIC HAEMODIALYSIS PATIENTS

Abstract Background and Aims Hypertension related to subclinical volume overload is a common clinical problem in hemodialysis patients. Lung ultrasound (LUS) is a validated technique for minute titration of dry weight, but has limited adoption in clinical practice because it is currently a physician (nephrologist)-led methodology and time consuming with 24-lung zones needing to be imaged. This study aims to show that (1) a simplified 8-zone LUS protocol is effective at dry weight titration in clinically euvolaemic chronic haemodialysis patients, as determined by 24-hour ambulatory blood pressure monitoring (ABPM), and that (2) nurse-led LUS for dry weight titration is feasible and safe. Method This was a 6-week pre and post intervention study in 13 clinically euvolemic haemodialysis patients with chronic hypertension. 4 senior dialysis nurses with at least 4 years of dialysis nursing experience respectively were trained in LUS image acquisition and interpretation via a 1 day workshop by a certified Nephrologist and passed an image interpretation test. 8-zone LUS (which has been described by Volpicelli et al.[1]) was performed midweek, weekly. A Nephrologist reviewed all the acquired LUS images retrospectively. Dry weight was titrated down at a rate not exceeding 0.3 kg per week if LUS Kerley B lines exceeded 3 in any lung zone. All patients underwent 24-hour ABPM at baseline and after 6 weeks. Nurses underwent a post study qualitative survey to elucidate success factors and confidence in LUS technique. Results The study cohort was predominantly male (69%) and diabetic (92%), with an average age of 68 ± 10 years. The average time required for a nurse to complete 1 LUS scan was 3 ± 0.4 minutes. 75% of the cohort had dry weight reduction post-study, which ranged from 0.08 – 0.9% of initial dry weight. Correspondingly, the median number of ultrasonographic B-lines reduced from 4 to 3, although this did not reach statistical significance. Overall, there were reductions in 24-hour systolic BP (146.42±17.03 vs 139.08±12.40 mmHg; p = 0.067) and diastolic BP (72.75±11.79 vs 70.75±11.69 mmHg; p = 0.561). Similarly, there were trends towards improvements in pre- and post-dialysis systolic and diastolic BPs, although only pre-dialysis diastolic BPs showed statistically significant improvement (80±16.05 to 72.33±13.32 mmHg, p = 0.046). This may be related to small sample size. Nil adverse outcomes such as intra-dialytic hypotension, vascular thrombosis, cardiovascular events or fluid overload were reported during the study. 1 patient demised from pneumonia sepsis, which was deemed to be unrelated to the study. All nurses expressed confidence in LUS image acquisition and interpretation following the workshop. Their confidence was further bolstered by the end of the study. They also felt that point-of-care LUS was a useful skill for experienced haemodialysis nurses who were often responsible for day to day adjustment of fluid removal on dialysis. Conclusion We have demonstrated that nurse-led 8-zone LUS can effectively and safely titrate dry weight in chronic haemodialysis patients, as evidenced by improvements in 24-hours ABPM. Importantly, these results are similar to that of randomized controlled trials such as the LUST study where LUS was physician-led. There remains little doubt about the importance of LUS in volume assessment. In-depth studies are required to determine the competencies of, and risk-benefit assessment for nurse-led LUS, to improve the clinical relevance and penetrance of this tool.

#2918 SERUM 25(OH)-VITAMIN D AND 1,25(OH)2 VITAMIN D IN HEMODIALYSIS PATIENTS: FACTORS AFFECTING THEIR CONCENTRATIONS AND THEIR EFFECT ON SURVIVAL

Abstract Background and Aims In haemodialysis patients, serum levels of vitamin D metabolites, 25-hydroxy-vitamin D (25D), a nutritional status of vitamin D, and 1,25-dihydroxy-vitamin D (1,25D), an active form of vitamin D, are previously reported to be low. In recent years of new CKD-MBD guidelines utilizing calcimimetics, vitamin D receptor agonists (VDRA) and new phosphate binders, relationship between serum 25D, 1,25D concentrations and clinical parameters in haemodialysis patients are not well known. We measured both serum 25D and 1,25D concentrations in chronic haemodialysis patients, and examined their association with several clinical factors and also with survival, in both cross-sectional and longitudinal analyses. Method A total of 108 stable haemodialysis patients (72 ± 10 year-old, 64 males, haemodialysis duration 6.9 ± 7.5 years, 45 with type 2 diabetes) were examined. Serum 25D was measured by a ECRIA method, and 1,25D by a RIA2 antibody method, and serum PTH by a IRMA assay. In a cross-sectional analysis, association of these vitamin D metabolites with clinical parameters was examined. In a longitudinal study, patients were followed for 3 years and survival of the patients was examined in relation with these vitamin D metabolites. Results Serum 25D concentrations were 12.0 ± 4.0 ng/ml, being hypovitaminosis D (<30 ng/ml) in all patients. Serum 1,25D concentrations were 14.7 ± 8.7 pg/ml, being lower than normal ranges (60-120 pg/ml) in 93% of the patients. There was no significant differences in 25D or 1,25D between those with diabetes and without. Although there was no significant correlation between 25D and haemodialysis duration, there was a significant negative correlation between 1,25D and haemodialysis duration (r = -0.187, p = 0.042). Neither of 1,25D or 25D was significantly correlated with serum calcium or phosphate concentrations. There was a significant, positive correlation between 25D and serum albumin (r = 0.172, p = 0.0454), although there was no significant correlation between 1,25D and serum albumin. Although there was no significant correlation between 25D and serum PTH, there was a significant, negative correlation between 1,25D and serum PTH (r = -0.379, p<0.001). Similarly, although there was no significant correlation between 25D and serum alkaline phosphatase, there was a significant, negative correlation between 1,25D and serum alkaline phosphatase (r = -0.309, p = 0.001). There were no significant differences in serum two vitamin D metabolites between patients with (n = 65) and without VDRA treatment, nor between those with (n = 12) and without calcimimetics. In a multiple regression analysis after adjustment of age, gender, haemodialysis duration, and VDRA treatment, serum 25D concentrations were significantly, independently associated with serum albumin (β = -0.244, p = 0.0149) (R2 = 0.125, p = 0.007). In a multiple regression analysis after the same adjustment, serum 1,25D concentrations were significantly, independently associated with serum intact PTH (β = -0.310, p = 0.003) (R2 = 0.200, p = 0.002). In the follow-up of three year, 16 patients died. Kaplan Meier analysis revealed that there tended to be better survival in patients with higher 25D concentration (n = 52) than those with lower concentration (p = 0.1936), although no significant association was seen between 1,25D and survival. Conclusion These results indicate that hypovitaminosis D (low 25D<30 ng/ml) is seen in all haemodialysis patients, and in most of these patients, serum 1,25D concentrations are low. Lower serum 25D concentrations are significantly associated with lower serum albumin, i.e., poorer nutritional status. Higher serum 1,25D, even in low ranges, is significantly associated with lower intact PHT and alkaline phosphatase, i.e. lower bone metabolism status. The results suggest that, in the era of new CKD-MBD treatments with calcimimetics and new VDRA, serum 25D may represent a nutritional status, and that serum 1,25D concentrations with regard to bone metabolism may be re-considered for the assessment of CKD-MBD, particularly in regards to prevention of secondary hyperparathyroidism.

#5203 THE INCESSANT QUEST FOR DRY WEIGHT: SHOULD WE ADOPT NEW STRATEGIES?

Abstract Background and Aims The estimate of the hydration state in the chronic hemodialysis patient is a key point of his care. Currently, there is no Gold Standard feasable in daily routine despite the increasingly numerous tools such as impedancemetry and pulmonary cardiac ultrasound. The objective of our study is to compare the results of the clinical estimation of dry weight with the results of impedancemetry and cardiac ultrasound results. Method This is a transverse study in the dialysis unit of Taher Sfar Mahdia hospital. The estimation of the hydration state was assessed before and after the hemodialysis session by the three above methods. The volume evaluation was carried out by a clinical score (NYHA> III dyspnea, orthopnee; jugular turgor (TJ), hepato-jugular reflux (HRJ), crackling in auscultation, peripheral edema and pre-dialysis hypertension); as well as by cardiac ultrasound (diameter of the lower vein, E/E ratio and systolic pulmonary arterial pressures). Results The values ​​measured by the different techniques decreased significantly after the hemodialysis session (p <0.001). At the two -stroke studied, we have objectified a significant correlation between the results of the impedancemetry, the index of the lower vein and its compliance. A significant difference between the results provided by the techniques studied and the results of the clinical evaluation was found in 64 % of patients. Only the orthopnee (p = 0.03) and the hepato-jugular reflux (p = 0.04) were significantly associated with the ultrasound overload diagnosis. Conclusion The existence of a difference between the subjective and objective target weight suggests the incessant need for a mixture between the different techniques evaluated. Our strategy requires to be adapted to the particularities of each patient.

#6814 A NEW SORBENT DEVICE FOR MULTIPLE CLINICAL PURPOSES: CURRENT EVIDENCE AT A PRIVATE HOSPITAL IN MEXICO

Abstract Background and Aims Adsorption is an extracorporeal technique utilized for blood purification, it also complements convection and diffusion for solute removal. Since 1991 we had used blood purification techniques, over the years, new adsorption cartridges had been developed, the new ones involving treatment for inflammatory conditions, chronic uremic symptoms and autoimmune diseases. HA130, HA230, and HA330 (Jafron, Zhuhai City, China) are among the widely used adsorption cartridges in China. We report highlights of the use of hemoperfusion using HA130 cartridges in the Mexican population cohorts in the context of multiple chronic inflammatory conditions in order to support evidence of effectiveness and safety. Method We retrospectively analyzed the medical records of 14 critically ill patients in the context of chronic inflammatory conditions such as acute kidney injury in chronic kidney disease, acute lung injury due to SARS-COV-2 infection and sepsis. Hemoperfusion in addition to standard therapy (fluid resuscitation, vasopressors, antimicrobial therapy and ventilatory support) resulted in the improvement of inflammatory substances levels when compared to standard therapy alone. Out of the 14 patients, 7 patients used HA130 cartridges and 7 patients with standard therapy alone. Results There were no significant side effects associated with HA130 cartridge use. HA 130 cartridges were found to be effective in reducing uremic symptoms in chronic hemodialysis patients, improvement of pruritus score and decreased parathyroid hormone and phosphate product (p<0.5) when compared to HD alone, creatinine (MARS: −24 μmol/L, −19.5 to −10.46, p < 0.001; SPAD: −2 μmol/L, −9.0 to +7.0/L, p = 0.314) and urea (MARS: −0.9 mmol/L, −318 to −0.189, p = 0.024; SPAD: −0.1 mmol/L, −1.0 to +0.68, p = 0.523). 66.6% of cost-effectiveness when compared to standard therapy. Conclusion In the group of patients that used HA130 cartridges we found statistically significant (p <0.05) reduction of pruritus score, PTH, phosphate product, creatine and urea when compared to the group of patients with standard therapy alone. The development in new cartridges technology allows more wide applications for renal patients. As we expand to involve other indications for this therapy there is cost-effectiveness improvement for the patients.More studies in different clinical settings are needed in order to achieve adsorption therapy national recommendations. We also found that the HA130 cartridges are effective in reducing uremic symptoms and microinflammatory status in acute kidney injury in chronic kidney disease patients due to the elimination of middle and small molecule uremic toxins and inflammatory mediators and endotoxins. This may translate as an improvement of quality of life and survive rates in patients with chronic hemodialysis, even though more studies are needed in order to prove this assumption.

#2871 BRAIN NATRIURETIC PEPTIDE LEVEL IN CHRONIC EGYPTIAN HEMODIALYSIS PATIENTS: ITS RELATION TO VENTRICULAR FUNCTION AND VOLUME STATUS

Abstract Background and Aims Volume overload is major problem in chronic hemodialysis patient and BNP level is related to volume status of the patient . Aims To assess BNP level in hemodialysis patient before and after HD session and to study its role as a marker for volume overload in hemodialysis patient depending on clinical findings and echocardiography parametershemodialysis. Method The study was conducted on 50 patients of Nephrology and hemodialysis unit, Mansoura University Hospital. Our patients were classified according to left ventricular mass index (LVMI) into patients with left ventricular hypertrophy (LVH)(35 patients) and patients without LVH (15 patients). We classified our patients into another two groups according to predialysis BNP level to group with BNP level˃100pg/ml(33 patients) which was associated with cardiac dysfunction and group with BNP level˂100pg/ml (17 patients). Results In the present study, the median of pre-dialysis BNP level was 126 pg/ml and the median of post- dialysis BNP was 25 pg/ml, this demonstrate that BNP plasma level decline after the hemodialysis session. Among The studied patients, the mean of predialysis systolic BP in patients with high BNP level ˃100 pg/ml is (155.65) higher than patients with low BNP level˂100 pg/ml . The incidence of lower limb edema, congested neck veins and chest crepitations was high in the group with BNP level (˃100 pg/ml) when compared with BNP level (<100 pg/ml). In the present study, according to ROC curve, predialysis BNP level may be a marker for lower limb edema with cutoff point (140.8) pg/ml with (85%) sensitivity and (77%) specificity and shows that the best cutoff point of predialysis BNP level in prediction of neck veins is (40.4) pg/ml with (94%) sensitivity and(28%) specificity and shows that the best cutoff point of predialysis BNP level in prediction of chest crepitation is (42.8) with (82%) sensitivity and (30%) specificity . Conclusion In Egyptian hempodialysis patients, there is a negative correlation between BNP predialysis and weight pre and post dialysis.There is significant correlation between BNP postdialysis and systoilc BP predialysis, RVD and COP. There is signifcant correlation between delta BNP and systoilc BP predialysis and ultrafiltration volume.

#6055 PATIENT REPORTED OUTCOMES AMONG DIALYSIS POPULATION IN STATE OF QATAR

Abstract Background Patients with (ESKD) undergoing dialysis, experience large burden of the disease and suffer variable symptoms that impact their health-related quality of life (HRQL). However, their symptoms are often under-recognized and under treated by their health care providers because they depend on objective measures such as physical examination and lab results. These examinations mostly don't reflect patients’ symptoms and the impact on health-related quality of life. Therefore, standardized subjective measures are important for symptoms screening and may improve symptom detection and treatment. Patient-Reported Outcome Measures (PROMs) are example of these measures and it capture patients’ symptom burden, level of functioning, and HRQL. PROMs can be used to evaluate and monitor aspects of patients’ health that may otherwise be overlooked, inform care planning, and facilitate the introduction of treatments. Aims To capture patients perceptions of their health and to address the HRQL symptoms in haemodialysis,to capture patients perception of their health and address the HRQL symptoms in chronic haemodialysis patients. To find the tools for follow up those HRQL symptoms. To encourage and promote patients patriation in care plan. Method Sample of 94 haemodialysis patients were included. We used two validated questionnaires to assess patients reported outcome (IPOS & EQ-5D) because there is no single instrument has established itself as the gold standard for measuring patient status. The (IPOS) captures symptoms such as, diarrhea, changes in skin color, restlessness, difficulty to sleep,itching,poor mobility, drowsiness, mouth sore, constipation, poor appetite,vomiting,nausea,weakness and renal scale. The (EQ-5D) is a standardized measure of health-related quality of life from five dimensions (Mobility, self-care, usual activities, pain, depression and anxiety). Results Majority of participants in this survey were male (n = 56; 60%). Middle eastern (67%), between the age of 19 to 77 (Mean = 53; STD =14). In the IPOS 50% of the patients reported the presence of symptoms such as difficulty of sleeping, itching, poor mobility, and general weakness. However, the severity of these symptoms varied from zero severity to overwhelming, 16% of patients were bothered by severe difficulties to sleep and poor mobility,15% had severe lack of energy,13% severe shortness of breath and 11% reported poor appetite. Pain was reported by 44% of patients out of which 33% expressed it as slight to moderate and 11% reported severe pain. The EQ-5D revealed that 47% have problem in walking, 41% of patients found to have difficulties in performing their usual activities, 27% of patients expressed feelings of depression and anxiety (22% mild to moderate and 5% severe).In addition 17% reported difficulties to perform self-care activities such as washing and dressing themselves. Conclusion Patients reported outcome is an important approach that captures patients’ perspectives of health and disease. PROM could result in improvement of health care delivery because it is a way to evaluate health care interventions effectiveness in a reliable and acceptable way that value patient's feedback. clinicians can utilize treatment aids to manage symptoms. Treatment aids are actionable assessment and treatment resources developed by expert clinicians and patient partners for the management of certain symptoms using these aids will help in tailoring patients therapy to improve outcome. And patients physician communication and improve quality performance.

#5221 PULMONARY HYPERTENSION: AN IMPORTANT RISK FACTOR IN CARDIOVASCULAR MORTALITY IN DIALYSIS PATIENTS

Abstract Background and Aims It is widely known that chronic dialysis patients experience significantly higher cardiovascular (CV) death rates than the overall population. Among other CV risk factors, recent research has shown pulmonary hypertension (PH) as a consequence of chronic kidney disease and end-stage renal failure. The present study aimed to determine the risk factors that impact survival in chronic haemodialysis and peritoneal dialysis patients and to analyse the correlation of these factors with pulmonary hypertension. Method We studied 125 stable haemodialysis and peritoneal patients (females 40%, mean age 52.42 ±11.88 years) on RRT for more than three months with a two-year follow-up. Demographic information, clinical characteristics, blood tests, and a thorough echocardiographic evaluation were collected at the optimal dry weight. After conventional echocardiographic examination, a tissue Doppler echocardiographic (TDE) examination was performed to evaluate the global and regional myocardial systolic and diastolic functions and pulmonary hypertension. Systolic pulmonary artery pressure (sPAP) of 35 mmHg was used to define PH. Results The cardiovascular mortality rate was 15.5%. In ROC analysis for CV mortality, the area under the curve (AUC) for PH and CRP was found 0.8; for LVM-I, E/E', and PP, the AUC was 0.76, 0.75, 0.72, respectively, while the inverse relationship was found with MASa and TASa with AUC = 0.66 and 0.95 respectively. According to the echocardiographic findings, PH was found in 28% (35 patients) of all patients. The mean PH was 33.46±5.38 mmHg. The higher level of higher parathormone (PTH), C-reactive protein (CRP), and E/E’ average, the lower left ventricular ejection fraction (EF), the peak systolic velocity at the lateral mitral annulus (MASa), and the peak systolic velocity at the lateral tricuspid annulus (TASa) were found to be predictors of PH. Patients evaluated with PH have a significantly lower cardiovascular survival rate [Long Rank (Mantel-Cox) p = 0.0001. Conclusion Our research demonstrates that cardiovascular morbidity and death in dialysis patients are mainly attributed to pulmonary hypertension, inflammation, vascular stiffness, and left ventricular hypertrophy. PH is common among dialysis patients. Inflammation, CKD-MBD biomarkers linked to systolic and diastolic left and right ventricular dysfunction, and inflammation all influence it. These conditions are all connected. Cardiovascular imaging is simple to use, offers a favourable viewpoint in the early identification of cardiac abnormalities and quick treatment of this disease, and is thus strongly advised in the dialysis population.

#5177 COVID-19 IN ELDERLY CHRONIC HEMODIALYSIS PATIENTS: PREDICTORS OF MORTALITY

Abstract Background and Aims Studies have shown that the incidence of severe COVID-19 pneumonia is higher in elderly patients and especially those with comorbidities including chronic kidney disease. The aim of our study was to determine risk factors for mortality in elderly chronic hemodialysis (HD) patients. Method We conducted a cross-sectional, observational, and analytical study, in the dialysis unit of the internal medicine department at Charles Nicolle Hospital over an 11-month period from September 2020 to August 2021. We studied the correlation between mortality and the different epidemiological, clinical and biological data via the SPSS software. Results We included 59 patients, with a mean age of 73 years [65-93] and a gender ratio of 1. All patients had confirmed COVID-19 infection, chronic kidney failure and required regular HD since at least 3 months. One on four patients had a coronary artery disease, 55% were diabetics and 72% had hypertension. From the 19 patients who underwent chest scan, 68% had severe lesions. Emergency HD had to be conducted for 25% of the patients, mainly because of hyperkalemia. At least one ongoing HD session was interrupted for neurologic, hemodynamic or respiratory instability in 26% of the patients. Mortality rate was 58%. Data that were associated with mortality in the univariate study were oxygen needs (p<10-3), COVID-19 infection severity (p=0.007), and interruption of HD session (p<10-3). Low blood pH levels and high pCo2 levels were also correlated to mortality (p=0.032 and p=0.020). Predictors of mortality in multivariate analysis were high oxygen needs (OR=1.368; 95% CI [1.081-1.732]; P = .009), interruption of HD session (OR=1.426; 95% CI [1.070-1.846]; P = .014) and severe form of COVID-19 infection (OR=1.770; 95% CI [1.062-2.980]; P = .029). Conclusion According to these results, high oxygen needs, severity of COVID-19 infection and interruption of HD session represented risk factors of death in elderly patients undergoing chronic hemodialysis. As highlighted in previous studies, mortality rate in COVID-19 seems to be higher among elderly patients. However, diabetes and cardiovascular diseases were not identified as predictors of mortality in this sample of patients.

#3255 BETA2 MICROGLOBULIN IS AN INDEPENDENT PARAMETER RELATED WITH DYSFUNCTION OF NATURAL KILLER CELL ACTIVITY IN HEMODIALYSIS PATIENTS

Abstract Background and Aims End-stage renal disease patients are characterized by immune dysfunction. Natural killer (NK) cells area lymphocytes of innate immune system that play a key role in an immune response towards viral infections and tumors. We aimed to analyze clinical factors related to the NK cell activity in chronic hemodialysis (HD) patients. Method Clinically stable 196 patients who were treated by HD for more than 3 months were enrolled from 4 outpatient HD clinics. NK cell activity was assessed using NK Vue assay (NKMAX, Sungnam, Korea) that uses serum of ex-vivo stimulated whole blood to detect interferon (IFN)-γ secreted from NK cells as an indicator of NK cell activity. All patients were stratified as abnormal (<250 pg/ml) and normal (≥250 pg/ml) groups according to NK cell activity. Results Mean age of the HD patients was 62.7 years [range 31 to 95 years] and mean HD duration was 49.2 months [range 3 to 221 months]. In total, 68 (35%) of HD patients showed abnormal NK cell activity. The abnormal NK cell activity group showed significantly increased age and shorter HD duration compared to the normal NK cell activity group (66.7 ± 11.9 vs. 60.6 ± 13.4 years, p = 0.001; 33.8 ± 33.0 vs. 57.5 ± 48.5 months, p<0.001, respectively). The serum albumin and parathyroid hormone levels were significantly lower in the abnormal NK cell activity group (3.7 ± 0.4 vs. 3.9 ± 0.3 g/dL, p = 0.005 and 176 ± 153 vs. 240 ± 260 pg/mL, respectively). In contrast, hemoglobin, blood urea nitrogen, urea reduction ratio, and C-reactive protein levels were comparable between the two groups. In multivariate regression analysis, old age, short dialysis duration, low serum albumin and high beta2 microglobulin levels were independent risk factors of abnormal NK cell activity in HD patients (adjusted odd ratio [AOR], 1.033; 95% confidence interval [CI], 1.005-1.062, p = 0.02; AOR, 0.981; 95% CI, 0.971-0.992; p<0.001, AOR, 0.395; 95% CI, 0.157-0.995; p = 0.049, and AOR, 1.042; 95% CI, 1.011-1.075; p = 0.008, respectively). Conclusion Our results suggest that young age and good nutrition as well as lower burden of middle molecule uremic toxin is associated with greater NK cell activity in HD patients.

#4520 THE USE OF FAR INFRARED LIGHT DURING HEMODIALYSIS SEEMS TO MAINTAIN ARTERIOVENOUS FISTULA BLOOD FLOW BETTER THAN USING A HEAT PAD - A PILOT STUDY

Abstract Background and Aims The use of the native arteriovenous fistula (AVF) in chronic hemodialysis (HD) patients yields great challenges to keep a patent AVF, especially among those with diabetes mellitus and cardiovascular disease. Often repeated radiological interventions or surgery of the AVF is necessary. Accumulation of advanced glycation end products (AGE) in tissue is shown to contribute to the complications of diabetes mellitus and uremia [1]. Far infrared light (FIR) irradiation of the AVF have shown protective effects in maintaining AVF blood flow [2,3]. Using a heat pad (HP) to stimulate vascular flow is another alternative. Primary aim of the study was to compare if the use of a HP is as good as FIR to maintain AVF blood flow. Secondary aim: Evaluate change in AGE accumulation in tissue after FIR and HP treatment. Method This pilot study included HD patients with a native lower arm AVF. Eighteen patients were randomly assigned to treatment during HD; Ten patients to FIR and another group of eight patients to use HP (Two of the HP-patients refused to fulfill the study). Before and after a period of 15 HD treatments each, blood tests, AVF blood-flow measured with a Transsonic® and skin autofluorescence (SAF, measuring AGE) were analyzed. The distance of the FIR emitter to the AVF puncture area was 25 cm. The HP-group was exposed to a waterfilled rubber HP that kept a temperature of 40-41°C and was positioned to the backside of the AVF arm to avoid dislodgement of or compressing needles. The patient was her/his own control and non-parametric Mann-Whitney U- and Wilcoxon sign ranked tests were used. Results The blood flow of the AVF was similar at start in the FIR group versus the HP-group median 921 ml/min IQR (714-1210) vs. 610 ml/min, IQR (538-861), p = 0.118, while after 15 treatments the blood flow was maintained in the FIR group but was lower in the HP-group; median 902 ml/min IQR (718-1241) vs. 635 ml/min IQR (531-772), p = 0.022. The FIR exposure did not alter the SAF content (in arbitrary units -AU) after treatment and was similar in the FIR group (median 3.2 AU, IQR 2.2-3.6) and in the HP group (median 3.2, IQR 2.4-3.3), p-value = 0.864.During the follow-up period after 3 and 6 months, PTA was performed due stenosis with decreased blood flow of the AVF in 3/10 patients in the FIR group and 1/6 patients in the HP group. Data are given as median and interquartile range (IQR). A two-sided p-value of <0.05 was defined as significant. Conclusion This pilot study showed that the access flow after FIR versus HP exposure during 15 HD treatments was better maintained among patients treated with FIR than with HP. SAF as a predictor for atherosclerosis was not changed. Long-term exposure to FIR may be necessary.

#2668 SUPERIOR BIOCOMPATIBILITY OF REGIONAL CITRATE ANTICOAGULATION COMPARED TO HEPARIN DURING EXPANDED HEMODIALYSIS WITH THERANOVA® MEMBRANE

Abstract Background and Aims Regional citrate anticoagulation (RCA) is known to improve the biocompatibility of hemodialysis (HD) by reducing complement, leukocyte and platelet activation. As continuous exposure to bio-incompatible HD may accelerate cardiovascular disease and increase mortality, improved biocompatibility may be important for clinical outcomes, including long-term survival of chronic HD patients. We found no reports of RCA during expanded hemodialysis (HDx), except our recent pilot study [1]. The aim of our trial was to compare RCA and full dose unfractionated heparin (UFH) during HDx with respect to biocompatibility parameters. Methods We performed a randomized, cross-over trial in 32 patients on chronic HD. Each had 2 HDx procedures with Theranova® membrane: one with UFH and one with RCA. RCA was achieved with 8% trisodium citrate at a flow rate of 150 mL/min. Anticoagulation with UFH was achieved by a bolus of 30 I.U. per kg of body weight, followed by an infusion of 18 I.U. per kg of body weight per hour. Anticoagulation was monitored by post-filter ionized calcium (RCA) or activated partial thromboplastin time (UFH). The primary outcomes were serum concentrations of C3a (marker of complement activation) and myeloperoxidase (MPO; marker of leukocyte activation) and plasma concentrations of platelet factor 4 (PF4; marker of platelet activation). Blood was drawn prior to, after 15 minutes and just before the end of HDx. The area under the biocompatibility marker concentration-time curve (AUC) was calculated for an individual biocompatibility marker from all three concentrations using the linear trapezoidal rule. As a secondary outcome, adhesion of blood cells and activation of clotting on inner surfaces of dialyzer fibers were visualized using scanning electron microscopy (SEM) in a subset of patients (n = 5). Biocompatibility parameters were compared between the groups using paired t-test or Wilcoxon signed-rank test. Results The trial included 22 males and 10 females. Patients were of mean age 65 ± 12 years with median dialysis vintage of 31 (IQR 17-89) months. Mean duration of HDx was 4.4 ± 0.4 hours (always the same for an individual patient). All patients had arteriovenous fistulas. Analysis of PF4 included only 8 patients, while the rest had concentrations of PF4 above the measuring range, probably due to unspecific platelet degranulation because of preanalytical factors. The concentrations of C3a, MPO and PF4 rose significantly after 15 minutes of HDx with UFH, while we observed no significant rises during HDx with RCA (Table 1). The AUC for biocompatibility markers were significantly smaller during HDx with RCA in comparison to UFH: 1163.0 ± 306.8 vs. 1444.1 ± 385.9 µgh/L for C3a (p<0.001); 78.2 (IQR 39.0-131.2) vs. 275.1 (IQR 136.9-492.9) µgh/L for MPO (p<0.001) and 100.0 (IQR 51.8-196.6) vs. 379.4 (IQR 295.0-553.0) IUh/mL for PF4 (p = 0.04). SEM showed almost no deposition on the membrane with comparable clotting score: 2 (IQR 1-3) for RCA vs. 2 (IQR 1-2.25) for UFH (p = 0.40). Conclusion Given the higher activation of complement, leukocytes and platelets during HDx with UFH, we conclude that RCA offers superior biocompatibility compared to UFH during HDx. Whether improved biocompatibility has clinical relevance remains to be explored.

#4894 EFFICIENCY AND SAFETY OF AN ASSISTED HOME HEMODIALYSIS PROGRAM IN THE STATE OF QATAR: A RETROSPECTIVE STUDY

Abstract Background and Aims Home hemodialysis (HHD) usually done as self-care by patient themselves through a portable haemodialysis (HD) machine under training and monitoring by dialysis team. HHD offers greater patient autonomy, cost benefits, treatment-related flexibility, and improved quality of life compared to traditional in-centre HD. Uptake of HHD is limited by patient motivation, cognitive and/or physical barriers, as well as lack of support of family and community. Assisted HHD (AHHD) is a new concept where dialysis team provides HD at home. Usually, it is done by a visiting dialysis nurse using mobile HD machine. Its use is limited due to financial and logistical restriction. We like to present our unique experience in providing AHHD in the State of Qatar. Planning for our AHHD program started in July 2020. Because of COVID-19 pandemic, it faced many challenges and delays. We started first patient in July of 2021. In our program, we use traditional HD machine (not portable) with connection set up in the house in a dedicated room. Special training was provided to AHHD staff regarding the special care needed for home setting (including social, complication of home dialysis settings, decision making, follow up of protocols and policies, etc.) Method We performed a retrospective study between July 1st, 2021 - December 31st, 2022. Our primary objectives were efficiency and safety of AHHD, and secondary objective was cost effectiveness. We included adult chronic HD patients (on HD >3 months) using ambulance (or eligible for it) with functional dialysis access. We excluded patients who are not suitable for home environment (psychiatric illness, aggressive behaviour, etc.). Data were collected from our national electronic health record system. Results 946 patients screened for the program. 237 were eligible (exclusion mostly due to lack of national insurance coverage or not meeting mobility/transport criteria). 121 patients refused to participate (mostly for feeling safer in the clinic setting or improper home environment), 40 patients were undecided, and 76 patients accepted and started AHHD. Age was 73+/-11 years. We had 32 males and 44 females. Mean follow up period were 7 months. 12 patients died and 2 patients returned to dialysis centre during follow up period. Only 15 out of the total 126 hospitalizations were related to dialysis (mostly due to volume overload and non-compliance with dialysis schedule and time). We had 55 patients with permcath and 21 with AV fistulas. We had 8 incidents of dialysis catheter malfunction (6 required tissue plasminogen activator installation in the house setting and only two needed catheter exchange (one had catheter related infection)). No reported significant access bleeding or hypotension episodes. We had 20 technical incidents during the study related to electricity or water supply failures. All incidents were resolved without much interruption of treatment. The program overall was cost effective and reduced cost by over 25% (mostly related to saving of ambulance cost). Patients and their families were very satisfied with the program overall. Conclusion We present a unique successful program related to providing AHHD. Targeting certain dialysis population showed great care, safety, cost saving, better QOL and satisfaction.

#2913 BLOODSTREAM INFECTIONS IN CHRONIC HEMODIALYSIS PATIENTS: CHARACTERISTICS AND OUTCOMES

Abstract Background and Aims Bloodstream Infections (BSI) are a major cause of death and hospitalization among hemodialysis (HD) patients. In recent years several preventive measures were introduced to reduce BSI in HD patients. Despite these various strategies, the rate of BSI in HD remains high. The aim of the present study was to explore factors associated with BSI in a contemporary cohort of HD patients at a public teaching hospital dialysis center. Method This was a retrospective cohort study of HD patients with a BSI in the years 2014 to 2018. The cohort included patients aged ≥ 18 years treated with chronic HD for at least three months. The primary outcome was the occurrence of BSI. We examined the clinical characteristics of the patients, causative pathogens, and mortality. Results The study involved 251 chronic HD patients. The mean age was 68.5±13.4 years, 69.9% were male. The most frequent cause of end-stage renal disease was diabetes (46.7% of patients). The mean time from initiation of HD was 34.8±40.8 months and the follow up period was 25.2±15.9 months. During the observation period, 44 patients (17.5%) developed 54 BSI events, while 9 of them (3.6% of the whole cohort) developed recurrent BSI events. Gram-negative microorganisms caused 46.3% of all BSI events. 31.4% of these BSI were caused by resistant bacteria. In multivariate logistic regression analysis, factors that increased the risk of mortality were BSI events (OR 2.566, p = 0.035), patients' age (OR 1.068, p<0.001), diabetes (OR 1.019, p = 0.001). Conclusion We noted an increased prevalence of gram-negative pathogens in the etiology of BSI in HD patients. Our findings highlight the need to be aware of local epidemiology in order to implement appropriate preventative measures and tailor empiric antibiotic therapy.

#3243 CANCER PATIENTS WITH END-STAGE KIDNEY DISEASE ON CHRONIC HEMODIALYSIS: CHANGING THE PARADIGM

Abstract Background and Aims In the last decade, new therapeutic regimens have dramatically improved the prognosis of cancer patients and changed the paradigm of a previously highly lethal disease, increasing the number of cancer patients with chronic kidney disease (CKD) who progress to end-stage kidney disease (ESKD). However decision-making regarding dialysis initiation in patients with cancer and ESKD remains however controversial. The aim of our study was to characterize the clinical course and evaluate survival outcomes of cancer patients on chronic hemodialysis (HD). Method We conducted a retrospective study of chronic HD patients in a single oncology hospital unit between January 1991 and November 2022. Outpatients on HD for more than one month, who underwent dialysis after the diagnosis of cancer were included. Univariate and multivariate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were estimated using the Cox proportional hazards risk model. Results Two hundred and twelve patients were recruited. Mean age at HD initiation was 65.7±14.7 years. The most prevalent ESKD etiologies were cast nephropathy, chronic interstitial nephritis, and surgical removal of the kidney. The most common tumors were genitourinary, multiple myeloma (MM) and gastrointestinal corresponding to 80.6% of all cancers. There were 143 deaths over a median follow-up period of 23 months (IQR: 7.25 – 54). The overall survival rates were 76.5% at 1 year, 59.6% at 3 years and 39.2% at 5 years. The median survival time was 44 months (95% CI: 30.58 – 51.42). An increased mortality risk was observed in patients with MM (HR: 3.38; 95% CI: 1.01-11.39; p = 0.045) and in those who started HD from 2001 to 2011 (HR: 1.60; 95% CI: 1.06-2.42; p = 0.001). The presence of metastasis or multiple tumors was not associated with all-cause mortality. Conclusion Our results highlight the importance of considering cancer patients for renal support therapies, including those with multiple tumors and metastatic disease. In fact, with the new treatments available, many patients have chronic oncological disease non-fatal in the short term. To the best of our knowledge, this is the largest study of cancer patients on chronic HD.

#3739 SHUNT PORTOSYSTEMIC COMPLICATED BY HYPERAMMONEMIA AND HEPATIC ENCEPHALOPATHY SUPPORTED BY DAILY DIALYSIS IN A CHRONIC HEMODIALYSIS PATIENT

Abstract Background and Aims Hepatic encephalopathy is a neuropsychiatric syndrome that may develop as a consequence of liver insufficiency. In acute liver failure, hepatic encephalopathy suggests the severity of the disease. In end-stage chronic liver diseases, episodes of hepatic encephalopathy are frequently fully and spontaneously reversible. Clinical manifestations vary from mild neuropsychiatric disorders to coma. The pathogenesis of hepatic encephalopathy is complex and not clearly understood. Ammonia plays a key role. In the healthy individual, ammonia is, during its first hepatic passage, directly degraded into urea, itself excreted by the kidney and the stools, and to a lesser degree in glutamine. Ammonia is also metabolized by the muscle striped. In case of liver failure and/or shunts portosystemic, there is a defect in hepatic clearance ammonia which is then found in excess in systemic circulation. Decreased muscle mass, linked to malnutrition, frequent in the patient cirrhotic and chronic hemodialysis, also helps to decrease metabolism ammonia. Due to the increase in permeability of the blood-brain barrier, the brain is exposed to excessive concentrations ammonia causing functional brain abnormalities and structural, which can partly explain the signs neurology of hepatic encephalopathy. In end stage chronic renal failure, clearance of ammonia via extracorporeal treatment has not been systematically evaluated. Several studies with small samples have demonstrated the effectiveness of hemodialysis, compared to peritoneal dialysis, in terms of ammonium purification in chronic renal failure, on dialysis or not on dialysis. The aim of this study was to evaluate the effectiveness of daily dialysis for the purification of ammoniumin a chronic hemodialysis patient with hepatic encephalopathy. Case Report A 40-year-old man undergoing chronic hemodialysis was referred to gastroenterology department of Mohammed VI University center of Marrakesh for inoperable shunt portosystemic complicated by hyperammonemia causing hepatic encephalopathy consisting of headaches and seizures. His medical history was significant for liver cirrhosis caused by infection with hepatitis B, end stage kidney disease due to membranoproliferative glomerulonephritis, for which the patient is on hemodialysis at the rate of 3 sessions per week. The patient went on to develop portal hypertension and ascites requiring frequent hospital admissions and treatment with diuretics. He was on a low-protein and low-sodium diet. While on oral furosemide 250 mg daily and spironolactone 100 mg daily, his diuresis was adequate. Before referral, this patient had already suffered 4 episodes of tonic clonic seizures. His 1st hemodialysis session in our training was on January 10, 2023, he was given daily hemodialysis sessions with daily blood tests, including immediate pre and post dialysis ammonia. Pre-dialytic ammonia levels varied between 103 and 161 µmol/l, as well as post-dialytic ammonia levels varied between 24 and 37 µmol/l, knowing that the normal value of laboratory ammonia varied between 10 and 51 µmol/l. The evolution was marked by a clear clinical improvement, with a disappearance of the seizures without a significant drop in ammonia after 14 daily hemodialysis sessions. Serum creatinine and urea declined, and sodium increased. Accumulation of ascites slowed and the patient could eat and sleep normally and was again independent with self care. The patient returned home on January 24. Conclusion This study shows the interest of daily hemodialysis sessions as a potential treatment for hyperammonemia in a patient on chronic intermittent hemodialysis, with a portosystemic shunt. The interest lies in the fact that the improvement is mainly clinical than biological (persistent hyperammonemia).

#6348 HFR USING A HIGH-FLUX DIALYZER (SUPRA-H) AS NEW EFFECTIVE ALTERNATIVE TO ON-LINE HEMODIAFILTRATION: A SINGLE SESSION ANALYSIS

Abstract Background and Aims Hemodiafiltration with regeneration of the ultrafiltrate (HFR) is a highly biocompatible dialysis technique that combines convection, diffusion, and adsorption. SUPRA-H is a new HFR system which uses a high-flux dialyzer in the diffusive stage to improve large uremic toxin removal. The aim of our study was to compare the toxin removal of the SUPRA-H system with high-volume online-hemodiafiltration (OL-HDF). Method In an open, randomized, cross-over, single-center, controlled study, 16 adult chronic hemodialysis patients were treated with SUPRA-H or OL-HDF. Hemodialysis sessions were delivered with Flexya dialysis monitor (Medtronic) in the middle-week session, lasting four hours. OL-HDF session was performed in post-dilution mode with the same high-flux dialyzer (Phylter HF17G, Medtronic) as that used in the diffusive stage of the SUPRA-H system. All other dialysis parameters were kept constant in both study arms. The reduction rate (RR) of urea, creatinine, phosphate, β2-microglobulin (β2mglob), kappa (κFLC) and lambda (λFLC) free light chains, interleukin-6 (IL-6) p-Cresyl sulfate, indoxyl sulfate and albumin, was intraindividually compared for the two dialysis types with linear mixed models. Results Whereas urea RR was significantly lower, SUPRA-H had significantly higher RR for κFLC (Median: 58.63%, IQR: 49.91-70.24) than those obtained with OL-HDF (Median: 51.97%, IQR: 37.12-62.71); p = 0.03). The RRs for the other large and protein-bound uremic toxins tended to be higher with the SUPRA-H system (Figure 1). There were no significant differences in the RRs for creatinine, phosphate, IL-6, and albumin. Conclusion The new HFR system SUPRA-H, appears to be a potential technologic step ahead in terms of improved large molecule removal for dialysis patients, and might contribute to a more adequate dialysis therapy.

#6715 COGNITIVE IMPAIRMENT IS ASSOCIATED WITH INCREASED MORTALITY IN HEMODIALYSIS PATIENTS

Abstract Background and Aims Patients on dialysis are at substantially higher risk for developing cognitive impairment compared with the general population. At the same time cognitive impairment is a strong and independent risk factor for all-cause mortality. Given that the approaches used to access the prevalence of cognitive disfunction widely vary in different patient populations, their true burden in hemodialysis patients remains poorly understood. The aim of our study was to determine the association between cognitive impairment and overall survival and mortality in patients undergoing hemodialysis treatment. Method A total of 69 chronic hemodialysis patients (47 men and 22 women) were included. The median age of patients was 61 [47-69] years. The median duration of hemodialysis treatment was 32 [21-72] months. The study of cognitive status was conducted using the Montreal Cognitive Assessment (MoCA) questionnaire. The test results are between 0 and 30 points. A score of 26 points or more is considered the norm, less than 26 indicates the presence of cognitive impairment. The end point was a fatal outcome from acute pathology or progression of a chronic disease. The analysis of survival and mortality was evaluated using survival tables, the construction of Kaplan-Mayer curves with the Mantel-Cox log–rank criterion. The risks of the influence of cognitive impairment on mortality were assessed using Cox regression. Results During the 24-month follow-up period, 23 patients died. Structure of mortality over the observation period: acute coronary syndrome – 6 (26 %), COVID-19 – 6 (26 %), acute cerebrovascular accident – 2 (9%), thromboembolic complications – 3 (13%), another causes – 6 (26 %). In patients with cognitive impairment on hemodialysis, the average survival value was 16.33 months ± 1.70 months [CI 95% 12.99-19.66] and 20.48 months±1.32 months [CI 95% 17.88-23.07] in patients without cognitive impairment. According to the Mantel-Cox log-rank criterion, there was a statistically significant decrease in overall survival in patients with cognitive impairment, P = .02. The mortality rate of dialysis patients with cognitive impairment was 51%, without cognitive impairment – 19%. Relative risk of death in the group of patients with cognitive impairment using Cox regression: Hazard ratio (HR) :2.90 [95% CI 1.11-7.37, P = .03]. Conclusion Our results support the notion that cognitive impairment may be an independent predictor of all-cause mortality in hemodialysis patients. There are limitations on the sample size of patients in our study. Further larger-scale observations a large cohort of patients are required.

#4524 TRIBOELECTRIC EVALUATION OF ARTERIOVENOUS FISTULA FOR HAEMODIALYSIS: A PILOT STUDY

Abstract Background and Aims Determination of stenosis in an arteriovenous fistula (AVF) for hemodialysis is an essential step in the management of patients with end-stage kidney disease. Stenosis, or narrowing of the blood vessels, can significantly reduce blood flow and ultimately lead to thrombosis and dysfunction of the AVF. Therefore, accurate and frequent surveillance is crucial for detection of stenosis and for the proper management of AVF. Surveillance of AVF is based on direct methods including ultrasound imaging and magnetic resonance angiography both dependent from examiner availability and not ever regularly repeatable. The triboelectric effect refers to the phenomenon where certain materials become charged after coming into contact with another material. In blood vessels the rubbing of erythrocytes against each other and arterial and vein wall generates a negative triboelectric charge and an electric potential range directly related to flow rate. The aim of our study was firstly to investigate the potential reliability of a wearable device able (Figure 1A) to record this constant potential and consequently evaluating the aptitude of waveforms generated to detect AVF stenosis in comparison to standard doppler evaluation. Method Between September 2022 and January 2023, we screened forty-eight patients from two hemodialysis centers in Catanzaro (Italy) Patients were divided in two groups basing on the assessment from two blinded experienced examiners for recognized criteria for stenosis: 2 major criteria (reduction of vessel size greater than 50% and a ratio between systolic peak velocity (SPV) in the stenotic region and SPV in pre-stenotic region major of 2 (>2)) and a supplementary finding like drop of the access flow [QA] below 500ml/min or drop of QA>25% as compared to the previous measurements in FAV with QA<1000ml/min or residual diameter <2mm). Patients were then evaluated using the PVDF/Kapton triboelectric sensor placed in contact with the skin on the lower surface, and with the thumb in contact with the upper surface to close the circuit and graphically recording typical pattern waveform generated. AVFs were analyzed considering the following acquisition sites: the chamber which corresponds to the site where surgery anastomosis was performed, a site located 5 cm from the chamber, and finally at the level of the humeral artery. Results There was an almost perfect (R = 0.97) correlation between the blood flow measured at the humeral artery level and the maximum-time derivative equation computed for each patient (Figure 1B). Based on doppler evaluation, 14/48 patients (29%) were classified as stenotic. Of these, 13 patients (93%) presented a typical wave pattern (B-point) with a ‘Notch’ shape (Figure 1D) which, conversely, was found in only 1 patient out of 34 without evidence of stenosis. The presence of Notch reflected the presence of stenosis with a Sensitivity of 92,8% (95%CI 66,1 to 99,8%), a specificity of 97% (95%CI 84,7 to 99,9%), holding an overall accuracy of 95,8% (95%CI 85,7% to 99,5%). Patients without stenosis assumed a different waveform (Figure 1C). Conclusions In chronic hemodialysis patients, the evaluation of AVF by a biosensor based on triboelectric potential measurement might represent an accurate and easy-to-perform surrogate of standard eco-doppler method for a quick and reliable evaluation of AVF functioning and, particularly, for a rapid risk stratification of patients with high suspect of AVF stenosis.

#3103 OMENTIN-1 AND SUBCLINICAL ATHEROSCLEROSIS IN ESKD PATIENTS UNDERGOING HEMODIALYSIS AND IN KIDNEY TRANSPLANT RECIPIENTS

Abstract Background and Aims In end-stage kidney disease (ESKD) patients, atherosclerosis is a key-player for cardiovascular risk, being influenced by endothelial dysfunction, inflammation and mineral dysmetabolism. Omentin-1 is an adipokine involved in various pathological conditions (diabetes, metabolic syndrome, obesity), and has recently been studied as a prognostic factor for atherosclerosis progression and mortality in the general population. In this study, we evaluated the possible relationships between Omentin-1 and incipient carotid atherosclerosis in the clinical setting of ESKD. Method Circulating blood Omentin-1 levels were measured in a cohort of 77 asymptomatic ESKD patients (40 kidney transplant recipients, Ktx and 37 chronic hemodialysis patients, HD) and in 30 healthy controls. Carotid intima-media thickness (cIMT) was measured before a single HD session or before a Ktx outpatient visit. Pathological cIMT was defined for mean values > 0.9 mm and/or an unilateral cIMT above the 75th percentile. Results Omentin-1 levels were higher in the entire ESKD cohort than in healthy controls (324 [90.3-770] vs. 110 [35.4-240.9] pg/ml; p = 0.03). Ktx patients had lower levels than HD patients (p = 0.01) while higher Omentin-1 levels were found in HD patients (474.9 [197.2-1432.1] ng/ml) compared to both healthy subjects (p = 0.009) and Ktx (p = 0.01). Mean cIMT in all ESKD was 0.78 ± 0.32 mm. 36 patients (46.7%) with pathological cIMT values displayed lower Omentin-1 levels as compared with others (168.7 [51.1-457.8] vs 474.9 [197.2-1432.1] and p = 0.004). Multivariate correlations analyses indicated Omentin-1 as the stronger independent predictor of carotid atherosclerosis (β-0.687; p = 0.03) in the whole cohort, even more than age, total cholesterol and diastolic BP. Conclusion In ESKD patients, Omentin-1 reflects the severity of carotid atherosclerosis independently from traditional confounders and may serve as an additive biomarker for risk prediction and risk stratification. Future studies are awaited to confirm these preliminary findings in larger cohorts.