Population Of Hemodialysis Patients Research Articles

Analyzing Monthly Blood Test Data to Forecast 30-Day Hospital Readmissions among Maintenance Hemodialysis Patients.

Background: The increase in the global population of hemodialysis patients is linked to aging demographics and the prevalence of conditions such as arterial hypertension and diabetes mellitus. While previous research in hemodialysis has mainly focused on mortality predictions, there is a gap in studies targeting short-term hospitalization predictions using detailed, monthly blood test data. Methods: This study employs advanced data preprocessing and machine learning techniques to predict hospitalizations within a 30-day period among hemodialysis patients. Initial steps include employing K-Nearest Neighbor (KNN) imputation to address missing data and using the Synthesized Minority Oversampling Technique (SMOTE) to ensure data balance. The study then applies a Support Vector Machine (SVM) algorithm for the predictive analysis, with an additional enhancement through ensemble learning techniques, in order to improve prediction accuracy. Results: The application of SVM in predicting hospitalizations within a 30-day period among hemodialysis patients resulted in an impressive accuracy rate of 93%. This accuracy rate further improved to 96% upon incorporating ensemble learning methods, demonstrating the efficacy of the chosen machine learning approach in this context. Conclusions: This study highlights the potential of utilizing machine learning to predict hospital readmissions within a 30-day period among hemodialysis patients based on monthly blood test data. It represents a significant leap towards precision medicine and personalized healthcare for this patient group, suggesting a paradigm shift in patient care through the proactive identification of hospitalization risks.

Transferrin levels are associated with malnutrition markers in hemodialysis patients in KwaZulu-Natal, South Africa

Introduction Malnutrition is a global phenomenon and may be contributing to the increasing size of the hemodialysis (HD) population in South Africa and is affecting morbidity and clinical outcomes. Our study assessed whether transferrin could be a possible marker for malnutrition in the HD population. Methods Clinical parameters (including skinfold thickness and mid-upper arm circumference [MUAC]) and laboratory markers (including transferrin and hemoglobin) were measured during a six-month period in a sample of 59 HD patients. Results Linear regression analysis showed that MUAC (p = 0.027) as well as skinfold thickness (p = 0.021) had a significant association with transferrin levels within the HD participants. There was no significant association between transferrin levels or MUAC with hemoglobin levels (p = 0.075). Furthermore, the study found that decreased transferrin levels (< 2.15 g/dL to 3.80 g/dL) were closely related to malnutrition in the malnutrition distribution groups within the study, with 97.7% of HD participants being classified in one of the malnutrition groups. Conclusion Thus, transferrin levels are a valuable marker for malnutrition within the HD patient population and can be included along with clinical assessment parameters such as MUAC and skinfold thickness as primary indicators for malnutrition.

One-Year Quality of Life Trend in a Large Population of Incident Hemodialysis Patients

One-Year Quality of Life Trend in a Large Population of Incident Hemodialysis Patients

Independent Predictors of One-Year Quality of Life Trend in a Large Population of Hemodialysis Patients: Importance of Vascular Access Management

Independent Predictors of One-Year Quality of Life Trend in a Large Population of Hemodialysis Patients: Importance of Vascular Access Management

The influence of Klotho protein and prooxidant-antioxidant balance combination on the mortality of HD patients.

End-stage renal disease patients on chronic hemodialysis (HD) have a shortened life expectancy compared to the general population. The aim of this study was to evaluate a possible link between three new and emerging factors in renal pathophysiology: Klotho protein, telomere length in peripheral blood mononuclear cells (TL) and redox status parameters before HD (bHD) and after HD (aHD), and to test mortality prediction capability of these emerging parameters in a population of HD patients. The study included 130 adult patients with average age 66 (54-72), on HD (3 times per week; 4-5h per session). Klotho level, TL, routine laboratory parameters, dialysis adequacy and redox status parameters: advanced oxidation protein products (AOPP), prooxidant-antioxidant balance (PAB), superoxide anion (O2.-), malondialdehyde (MDA), ischemia-modified albumin (IMA), total sulfhydryl group content (SHG), and superoxide dismutase (SOD) were determined. Klotho concentration was significantly higher aHD; 68.2 (22.6-152.9) vs. bHD 64.2 (25.5-119.8) (p = 0.027). The observed increase in TL was not statistically significant. AOPP, PAB, SHG, and SOD activity were significantly increased aHD (p > 0.001). The patients with the highest mortality risk score (MRS) had significantly higher PAB bHD (p = 0.002). Significantly lower O2.- (p < 0.001), SHG content (p = 0.072), and IMA (p = 0.002) aHD were found in patients with the lowest MRS values. Principal component analysis revealed redox balance-Klothofactor as a significant predictor of high mortality risk (p = 0.014). Decreased Klotho and TL attrition as well as redox status disturbance could be connected with higher mortality rate in HD patients.

Impact of the COVID-19 Pandemic in Spain in the Successive Pandemic Waves on Hemodialysis Patients and Healthcare Personnel.

(1) Background: The impact of SARS-CoV-2 has been variable over the time course of the pandemic and in different populations. The aim was to analyze the impact of COVID-19 infection in a known population of hemodialysis (HD) patients and professionals in Spain at different times of the pandemic. (2) Methods: We conducted an observational, descriptive study with a follow-up from 3 March 2020 to 23 April 2022 (776 days), using in average of 414 professionals and 1381 patients from 18 HD units in Spain. The data from the positive PCR or the rapid antigen detection test (RADT) subject were analyzed and segmented into six periods (waves). (3) Results: Of 703 positive COVID-19 tests, 524 were HD patients (74.5%), and 179 were HD professionals (25.5%). Overall, 38% of staff and 43% of patients were affected. Differences were observed in regard to incidence (21% vs. 13%), mortality (3.5% vs. 0%), and symptomatology between the patients and professionals and throughout the pandemic. (4) Conclusions: COVID-19 severity varied during different pandemic waves, with a greater impact seen in the first wave. HD professionals and patients had similar infection rates, but patients had higher mortality rates. Community transmission was the primary route of infection.

#4637 IS THE NEUTROPHIL/LYMPHOCYTE RATIO USEFUL IN PREDICTING THE OCCURRENCE OF DEPRESSION IN CHRONIC HEMODIALYSIS PATIENTS?

Abstract Background and Aims Depression is one of the most described psychiatric disorders in chronic hemodialysis patients. Previous studies have shown that the chronic inflammatory state is involved in the progression of depressive symptoms. The neutrophil/lymphocyte ratio (NLR) is an inexpensive and easily measured inflammatory marker. To date, the association between NLR and depression in this population in Morocco has never been described. Method In this multicenter cross-sectional study, we included a population of chronic hemodialysis patients over a period of 3 months (September- December 2023). The Patient Health Questionnaire-9 (PHQ-9) translated into Arabic (validated version) was used to assess depressive symptoms. NLR was calculated as the ratio of neutrophils to lymphocytes. An N/L ratio greater than 2.5 was considered high. We also used the patients' medical records to collect data on their biological tests and medical history. Results A total of 69 patients with a M/F sex ratio 1.2. The mean duration of HD was 7 ± 3.5 years, with a mean age of 53 ± 13.2 years. 28% were diabetic and 32% hypertensive. Depressive symptoms were detected in 20% of the 69 patients, and 72% of our patients had an NLR &amp;gt;2.5. In univariate analysis, PHQ-9 scores were positively correlated with NLR and negatively correlated with albumin. There was no correlation between PHQ-9 score and sex, age, duration of dialysis, diabetes, hypertension, ferritin. NLR was a significant predictor of mild (p = 0.06) and moderate or moderately severe (p = 0.04) depressive symptoms, after adjusting for age, gender, Kt/V, duration of dialysis, history of hypertension, diabetes and Charlson Comorbidity Index score. Conclusion These results suggest that NLR can be used as a biomarker to predict depressive symptoms in chronic hemodialysis patients.

#6792 VASCULAR ACCESS SURVIVAL OUTCOME IN ELDERLY HEMODIALYSIS PATIENTS: A SINGLE-CENTER RETROSPECTIVE STUDY

Abstract Background and Aims Elderly hemodialysis patients usually have lower life patency of vascular access than another age-group. Our center, elderly patients are the most of population of hemodialysis patients. Prior to initiate hemodialysis, planning of first vascular access has been established by patients, nephrologist, and vascular surgeon. The canulation technique for arteriovenous fistula (AVFs) has been determined by experienced hemodialysis-nurse and patient preferences. The aim of this study was to analyze the survival outcome of the access depending on the vascular type in the elderly. Method The study was collected retrospective data between Jan 1, 2013, and December 31,2022. We identified elderly patient (age ≥65) who initiate in-center hemodialysis and first-use vascular access in our center, including arteriovenous fistulas, graft, tunnel-catheter. Outcomes were vascular access patency and subgroup analysis for non-extreme elderly group and extreme (age ≥80) elderly group. A χ2 test, Kaplan-Meier analysis were performed. Results Overall number of elderly patients who initiated hemodialysis are 170: 63 AVFs-first (74% buttonhole cannulation technique), 21 grafts-first and 86 for tunnel-catheters. Mean survival of vascular accesses are higher in AVFs group (78 months in AVFs, 52.5 months in grafts, 53.3 months in tunnel-catheter P = 0.012). The outcome was consistency in the subgroup age 65-80 (80.9 months in AVFs, 47.3 months in grafts, 47.2 months in tunnel-catheter P = 0.005). However, mean vascular access survival did not differ in subgroup age &amp;gt;80 (56.3 months in AVFs, 58.4 months in grafts, 56.4 months in tunnel-catheter P = 0.98). Conclusion In our single center data, vascular access patency of elderly patients was highest in AVFs-first group and AVFs should be the first choice for elderly patients who would initiate hemodialysis especially non-extreme elderly group.

Visual Impairment in Hemodialyzed Patients-An IVIS Study.

Background and Objectives: The growing and aging population of hemodialysis patients has become increasingly disabled, with more complex comorbidities, and are older upon initiating dialysis. Visual impairment can adversely affect their quality of life and life satisfaction. Treatment evaluation should not only consider remission of the disease, but also the improvement of quality of life and life satisfaction. This is a single-center cross-sectional study. It was designed to evaluate visual impairment in hemodialyzed patients, its correlation with quality of life and life satisfaction, and its relationship to clinical outcomes in hemodialyzed patients. Materials and Methods: Seventy patients with chronic kidney disease undergoing hemodialysis and aged 18 years or older were recruited from a single Dialysis Unit. The Impact of Visual Impairment Scale (IVIS), WHOQOL-BREF, and Cantril Ladder questionnaires were utilized to assess both sociodemographic and clinical variables. Results: It was found that, among all assessed variables (i.e., sex, marital status, level of education, months on hemodialysis, history of kidney transplantation, Kt/V, URR, and UF), only age and central venous catheter placement were positively correlated with IVIS scores, while arteriovenous fistula and willingness to become a kidney transplant recipient were negatively correlated. Furthermore, a comparison between patients with moderate and severe visual impairment yielded supplemental data indicating that individuals whose dialysis access was through a dialysis catheter and those ineligible or unwilling to undergo transplantation suffered more often from severe visual impairment. This finding may be attributed to age. Conclusions: Older patients were predominantly observed to experience visual impairment. Patients intending to receive a kidney transplant and whose dialysis access was through an arteriovenous fistula were less prone to visual impairment, compared to those who may be ineligible or unwilling to receive transplantation and those with hemodialysis catheters. This phenomenon can be attributed to age-related distinctions in patients' suitability for specific dialysis access and transplantation. Those reporting visual impairment gave lower ratings in all four domains of their quality of life (comprising physical health, psychological health, social relationships, and environment) and in both present and anticipated five-year life satisfaction. More severe visual impairment was related to an additional reduction in physical health, social relationship, and environment domains, and in life satisfaction.

DEPRESSION AND ANXIETY IN HEMODIALYSIS PATIENTS

Objective:Depression and anxiety represent the most common expression of psychological distress in dialysis patients, and this distress is associated with a high mortality rate. Its prevalence, which varies from one study to another, remains underestimated. The objective of our study is to estimate the prevalence of depression and anxiety, in a population of chronic hemodialysis patients, and to identify the sociodemographic, clinical factors associated with them. Materials and Methods: Our study was carried out in the hemodialysis unit of the nephrology department of the Mohammed V military training hospital (HMIM V) in Rabat. It is a descriptive cross-sectional study conducted during June and July 2018, in 35 patients with chronic kidney failure, managed in periodic hemodialysis and who had given their free and informed consent to participate in the study. We used the Hospital-Anxiety and Depression Scale for the diagnosis of anxiety and depression. Results:Depression was found in 16 patients (45.7%) including 8 men and 8 women. The occurrence of depression was significantly related to gender, professional status, and the existence of somatic comorbidities. Anxiety was found in 21 patients (60%), including 10 men and 11 women. The occurrence of anxiety was significantly related to age, professional status, duration of professional status, duration of hemodialysis, existence of somatic comorbidities and professional status.

Effect of Protective Measures Adopted in the COVID-19 Pandemic on Hemodialysis Patients.

Introduction The use of masks and other preventive measures is nowadays an essential measure to prevent COVID-19 infections, particularly in hemodialysis patients. The aim of this study was to understand whether these protective measures adopted during the COVID-19 pandemic reduced or somehow contained the number of respiratory infections in a population of hemodialysis patients. Methods This was a longitudinal retrospective single-center study of hemodialysis patientswith at least six months of follow-upin a central hospital. A total of 103 patients were evaluated for the study. Two groups were defined: a control group that was followed in the year before the beginning of the pandemic and a group that followed in the year after its beginning. Results Patients in the pandemic group had a higher prevalence of previous major cardiovascular events (48.9% vs 8.6%) and heart failure (31.3% vs 12.1%) than those in the control group. Vaccination rates for influenza and pneumococcusas well as the monthly analytical results were similar in both groups. There were no significant differences in lower respiratory infections, hospitalizations caused by lower respiratory infections, and mortality between both groups. However, not accounting for aspiration pneumonias, the pandemic group had half the mortality due to respiratory infections (2.2% vs 5.2%). Conclusion Despite patients in the pandemic group having a similar prevalence of respiratory infections and hospitalizations motivated by lower respiratory infections, they presented about half the mortality of the control group. This suggests thatalthough there was no decrease in the number of infections, protective measures may have contributed to a decreased mortality.

Frailty status improvement after kidney transplantation.

Frailty is a clinical syndrome characterized by a decrease in strength, resistance and body physiological condition, making the individual more vulnerable, and increasing his/her risk of dependence and death. Kidney transplant (KT) is currently the best end-stage renal disease therapeutic alternative for certain individuals. Frailty status occurs in approximately 20% of KT patients. Thus, it was evaluated if there would be any change in frailty status level in a population of adult patients on chronic HD after receiving KT. A cross-sectional study was conducted on a population of adult hemodialysis patients (n: 57), with the objective of evaluating if there was a significant change in their clinical frailty score (CFS) after 6months of KT. For the statistical analysis, the Student's t-test, and the test of statistical significance between two proportions were applied. Mean CFS before KT was 4 (vulnerable), and after KT was 3 (robust). CFS value was significantly lower after KT (p value < 0.01). A significant improvement was found between pre- and post-transplant clinical frailty scores in hemodialysis adult patients.

Role of Lung Ultrasound in the Assessment of Hydration Status of Chronic Haemodialysis Patients

Background: Fluid overload is frequent in Haemodialysis (HD) and is one of the major factors of cardiovascular morbidity and mortality for chronic HD patients. The main challenge with chronic haemodialysis patients is indeed the maintenance of a normal extracellular volume through dry weight determination. Our study aimed at assessing the role of lung ultrasound in the detection of B-lines for the determination of hydration status in chronic HD patients. Methods: We conducted a cross-sectional study including 31 patients undergoing chronic HD treatment for at least 3 months, in the Yaounde University Teaching Hospital dialysis unit. Lung ultrasonography and clinical examinations were performed immediately before dialysis, and 30 minutes after dialysis. Differences between clinical and ultrasound variables before and after dialysis were measured to assess the effects of dialysis. Association between categorical variables was assessed with the Chi-squared test or Fischer test, and Rho’s Spearman coefficient for quantitative variables. Results: There was a reduction in the median of B-lines score after dialysis [12 (7 - 26) versus 8 (5 - 13)], clinical score [2 (1 - 3) versus 0 (-1 - 2)], mean of systolic blood pressure (164.74 ± 26.50 versus 158.48 ± 27.89), frequency of dyspnoea in patients (32.3% versus 6.5%); and raising of the frequency of cramps in patients (0% versus 19.4%) and all statistically significant (p ≤ 0.031). B-lines score before and after dialysis was associated with dyspnoea and raised jugular venous pressure (p < 0.05). B-lines score before dialysis was correlated with B-lines score after dialysis (r = 0.805; p < 0.001), B-lines reduction (r = 0.862; p < 0.001), and clinical score (r = 0.49; p = 0.005). Reduction of B-lines score was not correlated with weight loss. Conclusion: Lung ultrasound for the detection of B-lines reflects the variation of extracellular volume during dialysis and can even capture pulmonary oedema at a pre-clinical stage. It is then a reliable and sensible method for assessing extravascular lung water and thus hydration status of haemodialysis patients. It could constitute a better alternative for an objective and accurate definition of dry weight, specifically in the African and Cameroonian context, with its assets being low cost, availability, and easiness to perform in a large population of HD patients. We, therefore, recommend further multicentric studies in order to design a standardized protocol of ultrasound follow-up for all chronic HD patients’ hydration status assessments.

Biphasic Dynamics of Inflammatory Markers Following Hemodialysis Initiation: Results From the International MONitoring Dialysis Outcome Initiative

Inflammation is highly prevalent among patients with end-stage kidney disease and is associated with adverse outcomes. We aimed to investigate longitudinal changes in inflammatory markers in a diverse international incident hemodialysis patient population. The MONitoring Dialysis Outcomes (MONDO) Consortium encompasses hemodialysis databases from 31 countries in Europe, North America, South America, and Asia. The MONDO database was queried for inflammatory markers (total white blood cell count [WBC], neutrophil count, lymphocyte count, serum albumin, and C-reactive protein [CRP]) and hemoglobin levels in incident hemodialysis patients. Laboratory parameters were measured every month. Patients were stratified by survival time (≤6 months, >6 to 12 months, >12 to 18 months, >18 to 24 months, >24 to 30 months, >30 to 36 months, and >36months) following dialysis initiation. We used cubic B-spline basis function to evaluate temporal changes in inflammatory parameters in relationship with patient survival. We studied 18,726 incident hemodialysis patients. Their age at dialysis initiation was 71.3 ± 11.9 years; 10,802 (58%) were males. Within the first 6 months, 2068 (11%) patients died, and 12,295 patients (67%) survived >36 months (survivor cohort). Hemodialysis patients who died showed a distinct biphasic pattern of change in inflammatory markers where an initial decline of inflammation was followed by a rapid rise that was consistently evident approximately 6 months before death. This pattern was similar in all patients who died and was consistent across the survival time intervals. In contrast, in the survivor cohort, we observed initial decline of inflammation followed by sustained low levels of inflammatory biomarkers. Our international study of incident hemodialysis patients highlights a temporal relationship between serial measurements of inflammatory markers and patient survival. This finding may inform the development of prognostic models, such as the integration of dynamic changes in inflammatory markers for individual risk profiling and guiding preventive and therapeutic interventions.

Regional Differences in Quality of Life in a Large Multinational Population of Chronic Hemodialysis Patients

Regional Differences in Quality of Life in a Large Multinational Population of Chronic Hemodialysis Patients

Neuropathies périphériques et facteurs associés chez les hémodialysés chroniques du Bénin

IntroductionPeripheral neuropathies, in hemodialysis patients, are frequent. ObjectiveTo study peripheral neuropathies in the population of chronic hemodialysis patients in Benin. MethodsThis was a descriptive and analytical cross-sectional study conducted from April 1st to July 31st, 2017 in the hemodialysis units of the two public dialysis centers in Benin. Recruitment was exhaustive with inclusion of all patients with hemodialysis for more than 3months, aged at least 18years and consenting. The diagnosis of peripheral neuropathy was based on the presence of sensory-motor and/or vegetative disorders associated with amyotrophy, abolition or reduction of osteotendinous reflexes and absence of central signs. ResultsA total of 189 hemodialysis patients were included in the two public hemodialysis centers of Benin, 180 at the CNHU-HKM and 9 at the CHUD/BA. The mean age was 50.23±13.31years with extremes from 20 to 85 years and a sex ratio of 1.59. The overall frequency of peripheral neuropathy was 59.26%, including polyneuropathies (72.32%), unifocal mononeuropathies (10.71%), polyradiculoneuropathies (9.82%), and multiple mononeuropathies (7.14%). The associated factor in multivariate analysis was socioeconomic level (P=0.001; OR 39.41; 95% CI 4.81–322.64). ConclusionPeripheral neuropathy is frequent in chronic hemodialysis patients in Benin, requiring early detection and management.

Acid–base balance in hemodialysis patients in everyday practice

Introduction Abnormalities in blood bicarbonates (HCO3 –) concentration are a common finding in patients with chronic kidney disease, especially at the end-stage renal failure. Initiating of hemodialysis does not completely solve this problem. The recommendations only formulate the target concentration of ≥22 mmol/L before hemodialysis but do not guide how to achieve it. The aim of the study was to assess the acid–base balance in everyday practice, the effect of hemodialysis session and possible correlations with clinical and biochemical parameters in stable hemodialysis patients. Material and methods We enrolled 75 stable hemodialysis patients (mean age 65.5 years, 34 women), from a single Department of Nephrology. We assessed blood pressure, and acid–base balance parameters before and after mid-week hemodialysis session. Results We found significant differences in pH, HCO3 – pCO2, lactate before and after HD session in whole group (p < 0.001; p < 0.001; p < 0.001; p = 0.001, respectively). Buffer bicarbonate concentration had only statistically significant effect on the bicarbonate concentration after dialysis (p < 0.001). Both pre-HD acid–base parameters and post-HD pH were independent from buffer bicarbonate content. We observed significant inverse correlations between change in the serum bicarbonates and only two parameters: pH and HCO3 – before hemodialysis (p = 0.013; p < 0.001, respectively). Conclusions Despite the improvement in hemodialysis techniques, acid–base balance still remains a challenge. The individual selection of bicarbonate in bath, based on previous single tests, does not improve permanently the acid–base balance in the population of hemodialysis patients. New guidelines how to correct acid–base disorders in hemodialysis patients are needed to have less ‘acidotic’ patients before hemodialysis and less ‘alkalotic’ patients after the session.

MEASUREMENT OF PULSE WAVE VELOCITY IN HEMODIALYSIS PATIENTS

Objective: Cardiovascular complications represent the leading cause of death in chronic kidney disease. These patients combine classical and unconventional cardiovascular risk factors. Arterial stiffness, assessed by measuring the pulse wave velocity (PWV), is a reliable means of assessing cardiovascular risk. It has been rarely studied in hemodialysis patients. The purpose of our study was to evaluate the level of arterial stiffness by measuring carotid-femoral pulse wave velocity in a population of chronic hemodialysis patients and to investigate factors contributing to arterial stiffness. Design and method: We conducted a cross-sectional, descriptive study concerning the carotid-femoral pulse wave in hemodialysis patients during two years. Results: Our population included 38 chronic hemodialysis patients. Mean duration of hemodialysis was 29.21 ± 24.56 months. The mean age was 49 ± 13 years (16–78 years). Twelve patients were hypertensive (31.6%). Mean arterial pressure was 95 ± 13.5 mmHg. Hemoglobin value was 9.20 ± 1.66 g / dl. PTH was 714 ± 573 ng / l. PWV was 9.03 ± 2.73 m / s (5–16 m / s). Univariate analysis concluded that PWV acceleration was correlated with age, history of stroke, history of coronary artery disease, diabetes, HTA, elevated PTH and elevated CRP. Conclusions: A better understanding of factors influencing arterial stiffness, allows to intensify primary and secondary prevention in hemodialysis patients.

MO914: Development of Antibody Response to SARS-COV-2 Vaccines in Haemodialysis Patients

Abstract BACKGROUND AND AIMS Previous data has shown a reduced immune response shortly after SARS-CoV-2 vaccinations in haemodialysis patients. We therefore investigated the long-term antibody response in patients from different outpatient dialysis centres at 4 weeks and 6 months after a complete vaccination against COVID-19. The results were compared with the humoral responses of non-dialysis subjects. METHODS We designed a retrospective multicentric cohort study, enrolling 106 haemodialysis patients and 50 non-dialysis patients after the SARS-CoV-2 vaccination. SARS-CoV-2 antibody testing was performed as part of routine clinical practice 4 weeks as well as 6 months after the immunization with chemiluminescence immunoassays designed to detect antibodies against the SARS-CoV-2 spike protein (Elecsys Anti-SARS-CoV-2 S, Roche Diagnostics, Mannheim, Germany). Testing was performed in the Institute of Laboratory Medicine of the University Hospital Munich. According to the manufacturer's specifications, anti-SARS-CoV-2 S titres &amp;gt;0.8 U/mL are considered reactive (sensitivity 98.8% and specificity 99.9%). Anti-SARS-CoV-2 S titres &amp;lt; 100 U/mL were defined as a low antibody response. RESULTS A total of 106 haemodialysis patients with a median age of 73 years received a SARS-CoV-2 vaccination (n = 105 mRNA, n = 1 AstraZeneca). Of these, 50 non-dialysis patients with a median age of 56 years received a SARS-CoV-2 vaccination (n = 45 mRNA, n = 5 mRNA/AstraZeneca). During the observational period, 8 haemodialysis patients and 2 non-dialysis patients additionally contracted a SARS-CoV-2 infection. Between the two testings, an overall decrease in anti-SARS-CoV-2 S antibody titres was observed (haemodialysis patients from a median of 252 to 95 U/mL, non-dialysis patients from a median of 1621 to 441 U/mL). At 6 months after the complete vaccination, 99 (93%) haemodialysis patients still presented with a detectable anti-SARS-CoV-2 spike antibody response (&amp;gt;0.8 U/mL), comparable to 100% of the non-dialysis subjects. However, 60 (57%) haemodialysis patients showed low antibody response (&amp;lt;100 U/mL), whereas only 5 (10%) non-dialysis patients presented with low antibody response. Patients with an additional infection showed an increased titre of antibodies during follow-up. CONCLUSIONS Our data suggest regular antibody testing as well as a need for booster vaccination in the vulnerable population of haemodialysis patients.

Diminished Short- and Long-Term Antibody Response after SARS-CoV-2 Vaccination in Hemodialysis Patients.

Short-term studies have shown an attenuated immune response in hemodialysis patients after COVID-19-vaccination. The present study examines how antibody response is maintained after vaccination against SARS-CoV-2 in a large population of hemodialysis patients from six outpatient dialysis centers. We retrospectively assessed serum antibody levels against SARS-CoV-2 spike protein and nucleocapsid protein (electrochemiluminescence immunoassays, Roche Diagnostics) after COVID-19-vaccination in 298 hemodialysis and 103 non-dialysis patients (controls), comparing early and late antibody response. Compared to a non-dialysis cohort hemodialysis patients showed a favorable but profoundly lower early antibody response, which decreased substantially during follow-up measurement (median 6 months after vaccination). Significantly more hemodialysis patients had anti-SARS-CoV-2-S antibody titers below 100 U/mL (p < 0.001), which increased during follow-up from 23% to 45% but remained low in the control group (3% vs. 7%). In multivariate analysis, previous COVID-19 infections (p < 0.001) and female gender (p < 0.05) were significantly associated with higher early as well as late antibody vaccine response in hemodialysis patients, while there was a significant inverse correlation between patient age and systemic immunosuppression (p < 0.001). The early and late antibody responses were significantly higher in patients receiving vaccination after a SARS-CoV-2 infection compared to uninfected patients in both groups (p < 0.05). We also note that a higher titer after complete immunization positively affected late antibody response. The observation, that hemodialysis patients showed a significantly stronger decline of SARS-CoV-2 vaccination antibody titers within 6 months, compared to controls, supports the need for booster vaccinations to foster a stronger and more persistent antibody response.