Early start hemodialysis with a catheter may be associated with greater mortality: A propensity score analysis

INTRODUCTION

Deciding when and how to initiate hemodialysis (HD) is still controversial. An early start (ES) seems to show a lack of benefit. "Lead time bias" and comorbidities have been associated with different outcomes in ES groups. On the other hand, it is well accepted that the impact the type of vascular access (VA) has on patient survival. Our aim was to evaluate survival with early start (ES) versus late start (LS) on HD, taking into account the vascular access (VA) used.

METHODS

Between 01/1995 and 06/2018, 503 incidental patients initiated HD at our Dialysis Unit. eGFR was estimated by the CKD-EPI equation. Diabetes mellitus (DM), coronary disease (CD), and peripheral vascular disease (PVD) were considered comorbid conditions. According to eGFR and VA, patients were divided into four groups: G1: ES (eGFR > 7 mL/min) with catheter (ES + C), G2: ES with fistula or graft (F/G) (ES + F/G), G3: LS (eGFR< 7 mL/min) with catheter (LS + C), and G4: LS with F/G (LS + F/G). The cut-off value to define ES or LS was based on median eGFR for these 503 patients. We compared patient's survival rates by Kaplan-Meier and log-rank test. The four groups were compared before and after matching with propensity scores (PS). Cox analysis was performed to determine the impact of predictors of mortality.

RESULTS

Median eGFR was 7 (5.3-9.5) mL/min/1.73 m2 , median follow-up time was 30.9 (13-50) months, 52.1% had F/G access at entry, and 46.9% died during the observation period. Among the four groups, the ES + C were significantly older, and there were more diabetics and comorbid conditions, while phosphatemia, iPTH, albumin, and hemoglobin were significantly higher in the LS groups. Before propensity score (PS) matching, the ES + C group had a poor survival rate (p < 0.0001), while LS + F/G access had the best survival. After PS, a total of 180 patients were selected in the same four groups and ES + C kept showing a statistically significant poorer survival. Multivariate analysis revealed that ES + C was an independent predictor of mortality.

CONCLUSION

In this retrospective study, ES + C on HD was associated with a higher mortality rate than LS. This association persisted after PS matching.

Access to treatment in chronic kidney disease, dialysis and transplantation. Is there gender equality?

Sex and gender are often used as synonyms. However, while sex describes only a biological state, gender is a dynamic concept that takes into account psychosocial and cultural aspects of human existence that can change according to place and time. Inequality in medicine has been described in several areas. Among them, gender inequality has been disregarded for many years and is now a matter of concern. Chronic kidney disease (CKD) is a growing epidemic worldwide, affecting approximately 10% of the population. Although both men and women are affected, gender equality, especially in access to different treatments, is a matter of concern. We decided to investigate gender equality in patients with CKD. To this end, we conducted a literature narrative review to determine whether gender inequalities were found in CKD patients in general and in access to different treatment modalities in particular. A non-language restricted search was performed until November 30th 2022 in PubMed, SciELO, Trip Database, Google Scholar, MEDES y MEDLINE. We also investigated the situation in this regard in our country. We found that CKD is more prevalent in women than men, nevertheless this prevalence decreases along the CKD stages to the point that more men reach end stage kidney disease (ESKD) and dialysis. Access to transplant (ATT) is higher in men than in women although posttransplant survival shows no gender differences. Finally, most series have shown that women are more frequently Kidney transplantation (KT) living donors than men. Results in our country are similar to the published literature with the exception of a higher proportion of men as KT living donors. As in other areas, gender inequality in Nephrology has been largely overlooked. In this review we have highlighted gender differences in CKD patients. Gender inequality in Nephrology exists and needs to be looked upon in order to reach a personalized clinical approach.

Prospective cohort study of Torque Teno Virus (TTV) viral load kinetics and the association with graft rejection in renal transplant patients

INTRODUCTION

Graft survival is mainly determined by rejections and infectious complications in transplant recipients. Torque Teno Virus (TTV), a nonpathogenic and ubiquitous single-stranded DNA virus, has been proposed as a biomarker of the immune status in transplant patients. This study aimed to determine the correlation between a Home-Brew TTV PCR and R-GENE®PCR; the TTV viral load kinetics in renal transplant recipients and the association with graft rejection.

MATERIALS AND METHODS

Prospective cohort study on 107 adult renal transplant recipients. TTV viral load was determined in 746 plasma samples collected before and after renal transplantation by a Home-Brew PCR and a commercial PCR (R-GENE®PCR). Associations of TTV viral load with graft rejections were analyzed.

RESULTS

Agreement of both PCR assays was 93.2% and Pearson correlation coefficient was r: 0.902 (95%CI: 0.8881-0.9149, p < 0.0001). TTV viral load kinetics showed an initial gradual increase reaching a peak at 3 months. This highest value was followed by a slight decrease, reaching a plateau significantly higher than the initial baseline at 6 months (p < 0.0001). Between (181-270) days post-transplantation, TTV median viral load in patients with graft rejection was significantly lower, 3.59 Log₁₀ copies/mL (by Home-Brew PCR) and 3.10 Log₁₀ copies/mL (by R-GENE®PCR) compared to patients without graft rejection (6.14 and 5.96 Log₁₀ copies/mL, respectively).

CONCLUSIONS

Significantly lower TTV viral load was observed in patients with renal rejection occurring at a median of 243 days post-transplantation. Given the dynamic behavior of TTV viral load post-transplantation, cut-off values for risk stratification to predict rejection might be determined in relation to the post-transplant period.

Renal Transplantation in the Elderly: Are They All the Same? A Multicenter, Comorbidity-Based Study

INTRODUCTION

The age for kidney transplantation (KT) is no longer a limitation and several studies have shown benefits in the survival of elderly patients. The aim of this study was to examine the relationship of the baseline Charlson comorbidity index (CCI) score to morbidity and mortality after transplantation.

METHODS

In this multicentric observational retrospective cohort study, we included patients older than 60 years admitted on the waiting list (WL) for deceased donor KT from January 01, 2006, to December 31, 2016. The CCI score was calculated for each patient at inclusion on the WL.

RESULTS

Data for analysis were available of 387 patients. The patients were divided in tertiles of CCI: group 1 (CCI: 1-2) n = 117, group 2 (CCI: 3-4) n = 158, and group 3 (CCI: ≥5) n = 112. Patient survival was significantly different between CCI groups at 1, 3, and 5 years, respectively: 90%, 88%, and 84% for group 1, 88%, 80%, and 72% for group 2, and 87%, 75%, and 63% for group 3 (p < 0.0001). Variables associated with mortality were CCI score (p < 0.0001), HLA mismatch (p = 0.014), length of hospital stay (p < 0.0001), surgical complications (p = 0.048).

CONCLUSION

Individualized strategies to modify these variables may improve patient's morbidity and mortality after KT.

Assessment of the humoral response to the homologous Gam-COVID-Vac (Sputnik V) or heterologous Sputnik V/mRNA-1273 (Moderna) vaccination against SARS-CoV-2 in dialysis patients

BACKGROUND AND AIM

Dialysis patients are a high-risk population and have a reduced immune response to vaccination against SARS-CoV-2. The aim of this study was to assess the humoral response to homologous Gam-COVID-Vac (Sputnik V) and heterologous Sputnik V/mRNA-1273 (Moderna) vaccination in dialysis patients. The vaccination scheme depended on dose availability and the prioritization of risk populations as established by the Argentine Ministry of Health.

METHODS

Previous COVID-19 infection was determined in symptomatic patients. Binding IgG antibodies against the spike (S) receptor-binding domain (RBD) of SARS-CoV-2 (anti-S-RBD) concentration was assessed between 3 and 16 weeks after the boost dose. Anti-S-RBD antibodies were quantified using the Abbott Diagnostics SARS-CoV-2 IgG II Quant chemiluminescent microparticle immunoassay (CMIA) on an Architect i2000 SR and an Alinity I analyzer (Abbott Diagnostics, Abbott Park, Illinois, USA). To standardize the results to WHO binding antibody units (BAU), a correction factor for Abbott arbitrary units (AU) was applied where 1 BAU/mL equals 0.142 AU, as previously established by Abbott with the WHO international standard NIBSC 20-136. Following the manufacturer's recommendations, samples were considered reactive for anti-S-RBD when titers were above 50 AU/mL (7.2 BAU/mL). An 80% protective effect (PROT-80) against symptomatic SARS-CoV-2 infection was assumed when anti-S-RBD titers were 506 BAU/ml or higher. Charlson Comorbidity Index (CCI) score was classified as mild = 1-2, moderate = 3-4, and severe ≥ 5. Side effects were evaluated until day 7 by patients´ self-reported questionnaire.

RESULTS

One hundred seven participants were enrolled [n = 84 homologous (SpV/SpV), nn 23 heterologous (SpV/Mod)]. Median (IQR) age was 64 (50-75) years old and 79 (73.8%) were male. Additionally, 19 (22.6%) of the SpV/SpV and 4 (17.4%) of the SpV/Mod group had a prior confirmed SARS-CoV-2 infection (p = 0.589). In the overall population, 103 patients reached seroconversion (96.3%). Anti-S-RBD IgG median titers (IQR) were higher in the heterologous [1222 (288-5680) BAU/mL] than in the homologous scheme [447 (100-1551) BAU/mL], p = 0.022. In a linear model adjusted for age, gender, days from first vaccination to boost dose and days from the boost dose to the anti-S-RBD IgG determination, previous SARS-COV-2 infection (B: 2062.2; CI95: 1231.8-2892.6; p < 0.001), and SpV/Mod vaccination scheme (B: 1294.6; CI95: 435.58-2147.6; p = 0.003) were independently associated with anti-S-RBD levels. Finally, a higher frequency of adverse effects was associated with the heterologous scheme, although they were well tolerated by all individuals.

CONCLUSIONS

The present study provides evidence that the homologous SpV/SpV and heterologous SpV/Mod schemes showed good efficacy and safety in patients on chronic dialysis. These results could be useful for designing future vaccination strategies, especially aimed at this risk group.

Assessing Renal Function for Kidney Donation. How Low Is Too Low?

Kidney transplantation (KT) is the treatment of choice for patients with end-stage kidney disease (ESKD) with decreased morbi-mortality, improved life quality, and reduced cost. However, the shortage of organs from deceased donors led to an increase in KT from living donors. Some stipulate that living donors have a higher risk of ESKD after donation compared with healthy non-donors. The reason for this is not clear. It is possible that ESKD is due to the nephrectomy-related reduction in glomerular filtration rate (GFR), followed by an age-related decline that may be more rapid in related donors. It is essential to assess donors properly to avoid rejecting suitable ones and not accepting those with a higher risk of ESKD. GFR is a central aspect of the evaluation of potential donors since there is an association between low GFR and ESKD. The methods for assessing GFR are in continuous debate, and the kidney function thresholds for accepting a donor may vary according to the guidelines. While direct measurements of GFR (mGFR) provide the most accurate evaluation of kidney function, guidelines do not systematically use this measurement as a reference. Also, some studies have shown that the GFR decreases with age and may vary with gender and race, therefore, the lower limit of GFR in patients eligible to donate may vary based on these demographic factors. Finally, it is known that CrCl overestimates mGFR while eGFR underestimates it, therefore, another way to have a reliable GFR could be the combination of two measurement methods.

Seroprevalence of hepatitis B, hepatitis C and HIV infection among patients undergoing haemodialysis in Buenos Aires, Argentina

Introduction. Blood-borne infections are a major cause of harm in individuals on haemodialysis (HD). In particular, knowledge about hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV) status in HD patients is a major concern, since these infections may cause comorbidities in this setting. There is a paucity of data regarding this issue in Argentina.Hypothesis/Gap Statement. The epidemiological surveillance of HBV, HCV, and HIV is a fundamental tool for planning and implementing health strategies in order to prevent and control viral transmission of these viral agents.Aim. To determine the seroprevalence of HBV, HCV and HIV infections in HD patients in Buenos Aires, Argentina.Methodology. Seven hundred and forty-eight HD patients were included in a retrospective cross-sectional study. Serological assays were performed to determine HBV, HCV and HIV status. HBV HBsAg and anti-HBc IgG were analysed using AxSYM (samples before 2010) or the Architect Abbott system (samples since 2010), anti-HCV IgG testing was performed using the anti-HCV enzyme immunoassay AxSYM HCV V3.0 and ARCHITECT anti-HCV, while HIV was tested for using AxSYM HIV 1/2 gO and ARCHITECT HIV Ag/Ab Combination. HCV genotyping was carried out by phylogenetic analysis of the NS5B partial gene.Results. Infection with one of the viruses was detected in 31.1 % of patients [HBV in 82 (11.0 %), HCV in 179 (23.9 %) and HIV in 6 (0.8 %)]. Thirty-two (4.3 %) patients had 2 virus markers [27 (3.6 %) with HCV/HBV, 4 (0.5 %) with HCV/HIV and 1 (0.13 %) with HBV/HIV]. Finally, a single patient (0.13 %) presented all three markers. Time on dialysis was correlated with HCV but not with HBV infection. The HCV subtype distribution in HD patients was inverted with respect to that observed in the general population (HCV-1a 73.2 % and HCV-1b 26.8 % in HD vs HCV-1a 26.5 % and HCV-1b 73.5 % in the general population, P <0.001).Conclusion. Despite the implementation of universal precautionary biosafety standards for dialysis, infection with HBV and HCV continues to occur at very high rates in HD patients. The results emphasize the need to carry out proactive tasks for early diagnosis and treatment of infected individuals and to vaccinate those with non-protective antiHBs antibodies in order to reduce morbidity and mortality in HD patients.

Renal Transplantation in Patients Older Than 60 Years With High Comorbidity. Is There a Survival Benefit? A Multicenter Study in Argentina

BACKGROUND

The impact of renal transplantation (RT) in the elderly with many comorbid conditions is a matter of concern. The aim of our study was to assess the impact of RT on the survival of patients older than 60 years compared with those remaining on the waiting list (WL) according to their comorbidities.

METHODS

In this multicentric observational retrospective cohort study, we included all patients older than 60 years old admitted on the WL from 01 January 2006 to 31 December 2016. The Charlson comorbidity index (CCI) score was calculated for each patient at inclusion on the WL. Kidney donor risk index was used to assess donor characteristics.

RESULTS

One thousand and thirty-six patients were included on the WL of which 371 (36%) received an RT during a median follow-up period of 2.5 (1.4-4.1) years. Patient survival was higher after RT compared to patients remaining on the WL, 87%, 80%, and 72% versus 87%, 55%, and 30% at 1, 3, and 5 years, respectively. After RT survival at 5 years was 37% higher for patients with CCI ≥ 3, and 46% higher in those with CCI < 3, compared with patients remaining on the WL. On univariate and multivariate analysis, patient survival was independently associated with a CCI of ≥3 (hazard ratio 1.62; confidence interval 1.09-2.41; P < 0.02) and the use of calcineurin-based therapy maintenance therapy (hazard ratio 0.53; confidence interval 0.34-0.82; P < 0.004).

CONCLUSIONS

Our study showed that RT improved survival in patients older than 60 years even those with high comorbidities. The survival after transplantation was also affected by comorbidities.

Reduced survival in patients who return to dialysis after kidney allograft failure

BACKGROUND

The outcome of patients who return to dialysis after Kidney allograft failure (KAF) remains unclear. Our aim was to compare the outcome of KAF patients vs two different types of transplant naive incident dialysis (TNID) patients, those on the waiting list (WL) and those with a kidney transplant contraindication (KTC).

METHODS

We performed an observational study using data from the Argentinian Dialysis Registry between 2005 and 2016. We compare mortality between KAF, WL, and KTC.

RESULTS

We included 75 722 patients of which 2734 were KAF. Survival between the three cohorts (KAF vs WL (n = 14 630) vs KTC (n = 58 358) revealed a significant difference (log-rank test: P < .0001) indicating worse survival for KTC patients and best survival for WL. We found that KAF patients had as poor outcome as KTC patients after multivariate adjustment. Cox regression showed that age >65 years: HR: 1.845 (1.79-1.89) P < .0001, transient catheter: HR: 1.303 (1.26-1.34) P < .0001, diabetic: HR: 1.273 (1.22-1.31) P < .0001, hepatitis C: HR: 1.156 (1.09-1.22) P < .0001, and albumin: HR: 1.247 (1.21-1.28) P < .0001 were associated with mortality.

CONCLUSION

Patients who return to dialysis after KAF have higher mortality than WL patients and similar to KTC patients.

P1729HEMODYNAMIC AND AUTONOMIC PERFORMANCE IN CHRONIC DIALYSIS AND RENAL TRANSPLANT PATIENTS. IS THERE AN IMPROVEMENT?

Background and Aims

Chronic kidney disease (CKD) is a major public health problem, with high prevalence worldwide. It’s associated with high morbidity and mortality, especially in the advanced stage when substitution therapies are needed. It’s well established that Ps with end-stage kidney disease have increased mortality due to an elevated incidence of cardiovascular diseases (CVD). The best treatment for this population it’s definitely the kidney transplant (KT), mostly because it improves the quality of life and reduces global and CV mortality compared with Ps treated with chronic dialysis (Dx). There is not a convincing explanation about the physiological mechanisms involved in this improvement. Impedance cardiography (IC) it’s a well established, validated method to asses hemodynamics parameters.

Study and describe the differences between hemodynamic and autonomic profiles between KT and Dx Ps using IC.

Method

We studied 331 Ps as part of a cardiovascular evaluation program in Ps with ESKD which is being carried out in our institution (CEMIC, Buenos Aires). Of these, 190 were on Dx and 141 on KT. Non-invasive hemodynamic assessment was performed using IC (Z Logic- Exxer SA) in supine and standing position, taking into account the following variables: heart rate (HR), thoracic fluid content (TFC), stroke volume (SV), systemic vascular resistance index (SVRI), arterial compliance index (ACI), and pre-ejection period (PEP). Ps in the Dx group were studied on the interdialytic day. We evaluated the autonomic profile by studying the variability of HR (Kubios Finland) for three minutes, with measurements of the spectral components, high frequency (HF), low frequency (LF), total power (totpowar) and the ratio LF/HF. We compared absolute supine variables and then the differences between supine and standing positions. Exclusions criteria: less than six months of KT or Dx; incomplete basic hemodynamic study or lack of data; amputation; previous KT.

Results

We included 107 Ps of Dx and 118 of KT. No significant differences were detected in terms of age, sex, diabetes, and antihypertensive treatment. Ps on Dx had more prevalence of hypertension and CVD. Those in KT group had a median time of 72,5 months of transplantation and 46 months of prior dialysis time, with a media of eGFR (CKD-Epi) of 56 ml/min/1,72 m2. Ps on Dx had a median of 22 months on substitution treatment. The hemodynamic evaluation showed that KT Ps had lower HR (p=o,oo1), higher ACI (p=0,002) and PEP (p=0,05), and a tendency of higher SV (p=0,07). The autonomic evaluation showed no significant differences between the two groups, though the totpowar had a tendency to be higher in the KT group with a median of 367(200-625) compared with 248 (103-465) in the Dx group (p=0,07). The changes in the variables during the standing position evidenced that Ps on Dx had a lower elevation of HR (p=0,04) and SVRI (p&lt;0,001). We assessed the prevalence of orthostatic hypotension defined as a reduction of the SBP in 20 mmHg and/or the DBP in 10 mmHg after standing up. The Dx group had a prevalence of 30% and the KT group of 20%, but the difference was not significant.

Conclusion

Ps with KT seems to have a better hemodynamic profile than those on Dx, mainly, a better vascular response with a more physiological- compensatory elevation of HR and VSRI when they stand up. Although the autonomic activity showed no significant statistical difference, the total power, an expression of the whole autonomic activity, showed us a clear tendency in favor of KT, which needs to be confirmed with a larger size sample.

Surveillance Registry of Sirolimus Use in Recipients of Kidney Allografts From Expanded Criteria Donors

BACKGROUND

The use of expanded criteria donor (ECD) kidneys has increased the overall availability of renal transplants. This study assessed the use of sirolimus in patients receiving Argentina-ECD kidneys.

METHODS

This observational, open-label, 1-arm, prospective, longitudinal pilot study was conducted at 8 transplant centers in Argentina. Adults receiving kidney transplants (without pancreas) from ECDs were eligible if they were converted to sirolimus 1 to 36 months' posttransplantation, with sirolimus becoming base therapy within 1 month after conversion. Patients were followed up for 1 year. Outcomes included reasons for conversion, acute rejection, patient and graft survival, graft status, and safety.

RESULTS

The intention-to-treat population included 52 patients (mean age, 48.7 years). Calcineurin inhibitor nephropathy (40%) and chronic allograft nephropathy (25%) were the most frequent reasons for conversion. Two acute rejections occurred during follow-up, but no patients experienced graft loss. One patient died during follow-up, and 3 patients died within 1 month of the last sirolimus dose. Levels of serum creatinine and creatinine clearance remained stable from baseline to week 52/53. Mean proteinuria measured in a subset of patients was 0.2 ± 0.2 g/24 hours before conversion and increased to 0.6 ± 1.2 g/24 hours at week 24/25 and 0.5 ± 0.6 g/24 hours at week 52/53. Adverse events were consistent with those in previous conversion trials; the most common were infections and infestations (54%).

CONCLUSIONS

This pilot study illustrates the potential benefits of sirolimus in recipients of ECD kidneys in Argentina. Larger, randomized controlled trials are needed to confirm these findings and to clarify the long-term benefits of sirolimus in this patient population.

[Acute peripheral demyelinating polyneuropathy and acute renal failure after administration of FK506]

FK 506 is a potent immunosuppressive agent in clinical use in solid organ transplantation since 1989. Approximately 5% of patients receiving FK 506 develop major central nervous system toxicity but peripheral nervous system involvement is very uncommon, and there are only 4 reported cases of demyelinating polyneuropathy in patients who received a liver transplant. We report a case of demyelinating polyneuropathy associated with the use of FK 506 in a renal transplant recipient.

Short term effects of air pollution on mortality in the city of Lyon, France, 1985-90

OBJECTIVE

The short term association between daily mortality and ambient air pollution in the city of Lyon, France (population, 410,000) between 1985 and 1990 was assessed using time series analysis.

DESIGN

This study followed the standardised design and statistical analysis (Poisson regression) that characterise the APHEA project.

METHODS

Four categories of cause of death were studied: total (minus external causes), respiratory, cardiovascular, and digestive causes (as a control condition).

RESULTS

No association was found with any cause of death for nitrogen dioxide (NO2) and ozone (O3), nor, for any pollutant, for digestive conditions. Sulphur dioxide (SO2) and, to a much lesser degree, suspended particles (PM13), were significantly related to mortality from respiratory and cardiovascular conditions. The relative risk (RR) of respiratory deaths associated with a 50 micrograms/m3 increment of mean daily SO2 over the whole period was 1.22 (95% CI 1.05, 1.40); the RR for cardiovascular deaths was 1.54 (1.22, 1.96). The corresponding RRs for PM13 were 1.04 (1.00, 1.09) for respiratory mortality and 1.04 (0.99, 1.10) for cardiovascular deaths.

CONCLUSIONS

The effects of particulates were slightly increased during the cold season. When particulates concentrations were greater than 60 micrograms/m3, the joint SO2 effect was increased, suggesting some interaction between the two pollution indicators. These results agree with other studies showing an association between particulate pollution and daily mortality; however, they also suggest the noxious effect of SO2.