Delivering Person-Centered Peritoneal Dialysis.

Peritoneal dialysis (PD) enables people to have a home-based therapy, permitting greater autonomy for individuals along with enhanced treatment satisfaction compared with in-center dialysis care. The burden of treatment on PD, however, remains considerable and underpins the need for person-centered care. This reflects the need to address the patient as a person with needs and preferences beyond just the medical perspective. Shared decision making is central to the recent International Society for Peritoneal Dialysis recommendations for prescribing PD, balancing the potential benefits of PD on patient well-being with the burden associated with treatment. This review considers the role of high-quality goal-directed prescribing, incremental dialysis, and remote patient monitoring in reducing the burden of dialysis, including an approach to implementing incremental PD. Although patient-related outcomes are important in assessing the response to treatment and, particularly life participation, the corollary of dialysis burden, there are no clear routes to the clinical implementation of patient-related outcome measures. Delivering person-centered care is dependent on treating people both as individuals and as equal partners in their care.

Mortality Rates in Transplant Recipients and Transplantation Candidates in a High-prevalence COVID-19 Environment.

BACKGROUND: The risk of COVID-19 infection in transplant recipients (TRs) is unknown. Patients on dialysis may be exposed to greater risk of infection due to an inability to isolate. Consideration of these competing risks is important before restarting suspended transplant programs. This study compared outcomes in kidney and kidney/pancreas TRs with those on the waiting list, following admission with COVID-19 in a high-prevalence region. METHODS: Audit data from all 6 London transplant centers were amalgamated. Demographic and laboratory data were collected and outcomes included mortality, intensive care (ITU) admission, and ventilation. Adult patients who had undergone a kidney or kidney/pancreas transplant, and those active on the transplant waiting list at the start of the pandemic were included. RESULTS: One hundred twenty-one TRs and 52 waiting list patients (WL) were admitted to hospital with COVID-19. Thirty-six TR died (30%), while 14 WL patients died (27% P = 0.71). There was no difference in rates of admission to ITU or ventilation. Twenty-four percent of TR required renal replacement therapy, and 12% lost their grafts. Lymphocyte nadir and D-dimer peak showed no difference in those who did and did not die. No other comorbidities or demographic factors were associated with mortality, except for age (odds ratio of 4.3 [95% CI 1.8-10.2] for mortality if aged over 60 y) in TR. CONCLUSIONS: TRs and waiting list patients have similar mortality rates after hospital admission with COVID-19. Mortality was higher in older TRs. These data should inform decisions about transplantation in the COVID era.

Identification of Patient Characteristics Associated With SARS-CoV-2 Infection and Outcome in Kidney Transplant Patients Using Serological Screening.

BACKGROUND: From population studies, solid organ transplant recipients are at increased risk of mortality from RT-PCR confirmed COVID-19 infection. The risk factors associated with infection acquisition and mortality in transplant recipients using serological data have not been reported. METHODS: From 1725 maintenance transplant recipients, 855 consecutive patients were screened for SARS-CoV-2 antibodies. Serological screening utilized assays to detect both the N protein and receptor binding domain antibodies. Thirty-three of 855 (3.9%) of the screened patients had prior infection confirmed with RT-PCR. Twenty-one additional patients from our 1725 maintenance cohort with RT-PCR confirmed infection were included in our analysis. RESULTS: Eighty-nine of 855 (10.4%) patients tested positive for SARS-CoV-2 antibodies. Fifty-nine of 89 (66.3%) cases were patients newly identified as exposed, while 30/89 (33.7%) seropositive patients had previous infection confirmed by RT-PCR. A diagnosis of SARS-CoV-2 (RT-PCR or Ab+) was associated with being from a noncaucasoid background, P = 0.015; having a diagnosis of diabetes, P = 0.028 and a history of allograft rejection, P < 0.01. Compared with the RT-PCR+ cohort, patients with serological-proven infection alone were more likely to be receiving tacrolimus monotherapy, P < 0.01, and less likely to have a diagnosis of diabetes, P = 0.012. Seventeen of 113 (15.0%) of all patients with infection (RT-PCR and Ab+) died. Risk factors associated with survival were older age, odds ratio (OR): 1.07 (1.00-1.13), P = 0.041; receiving prednisolone, OR: 5.98 (1.65-21.60), P < 0.01 and the absence of diabetes, OR: 0.27 (0.07-0.99), P = 0.047. CONCLUSIONS: This study identifies risk factors and outcome for COVID-19 infection incorporating data on serologically defined infection and highlights the important contribution of immunosuppression regimen on outcomes.

Informing the Risk of Kidney Transplantation Versus Remaining on the Waitlist in the Coronavirus Disease 2019 Era.

INTRODUCTION: There are limited data pertaining to comparative outcomes of remaining on dialysis versus kidney transplantation as the threat of coronavirus disease 2019 (COVID-19) remains. In this study we delineate the differential risks involved using serologic methods to help define exposure rates. METHODS: From a cohort of 1433 patients with end-stage kidney disease (ESKD), we analyzed COVID-19 infection rates and outcomes in 299 waitlist patients compared with 237 transplant recipients within their first year post-transplant. Patients were followed over a 68-day period from the time our transplant program closed due to COVID-19. RESULTS: The overall mortality rates in waitlist and transplant populations were equivalent (P = 0.69). However, COVID-19 infection was more commonly diagnosed in the waitlist patients (P = 0.001), who were more likely to be tested by reverse transcriptase polymerase chain reaction (P = 0.0004). Once infection was confirmed, mortality risk was higher in the transplant patients (P = 0.015). The seroprevalence in dialysis and transplant patients with undetected infection was 18.3% and 4.6%, respectively (P = 0.0001). After adjusting for potential screening bias, the relative risk of death after a diagnosis of COVID-19 remained higher in transplant recipients (hazard ratio = 3.36 [95% confidence interval = 1.19-9.50], P = 0.022). CONCLUSIONS: Although COVID-19 infection was more common in the waitlist patients, a higher COVID-19‒associated mortality rate was seen in the transplant recipients, resulting in comparable overall mortality rates.

Donor-specific antibodies detected by single antigen beads alone can help risk stratify patients undergoing retransplantation across a repeat HLA mismatch.

Whether reexposure to mismatched HLA antigens (RMM) in the setting of a negative crossmatch is associated with increased immunological risk remains an area of uncertainty. This is due to evidence derived predominantly from registry data, which lacks comprehensive information on alloantibody and rejection. In this study, we analyze the impact of low-level preformed donor-specific antibodies (DSA) against an RMM on transplant outcomes. From 1988 consecutive renal transplant recipients, we analyzed 179 patients undergoing retransplantation, of whom 55 had a RMM. All patients were crossmatch negative and preformed DSA were detected by single antigen beads alone. Multivariate analysis revealed that patients with preformed DSA against an RMM were independently at risk of antibody-mediated rejection (HR 8.70 [3.42-22.10], P < .0001) and death-censored allograft loss (HR 3.08 [1.17-8.14], P = .023). In addition, prior transplant nephrectomy (HR 2.04 [1.00-4.17], P = .0495) was also associated with allograft failure, whereas receiving a retransplant that was matched at HLA class II was associated with a favorable outcome (HR 0.37 [0.14-0.99], P = .047). In the absence of preformed DSA, an RMM was not associated with de novo DSA development, rejection, or allograft loss. In conclusion, an RMM portends increased immunological risk only in the presence of a preformed DSA in patients undergoing retransplantation.

Allosensitization after transplant failure: the role of graft nephrectomy and immunosuppression - a retrospective study.

There are conflicting data about the role of transplant nephrectomy and immunosuppression withdrawal on the development of allosensitization and the impact on re-transplantation. We divided 109 first graft recipients into two groups according to whether they underwent nephrectomy (NX+, n = 61) or their graft was left in situ (NX-, n = 48). Sera were assessed for HLA-A/B/Cw/DR/DQ antibodies at the time of NX/transplant failure and after 3, 6, 12, 24 months. The NX+ group showed a higher rate of donor specific antibody (DSA) and non-DSA human leukocyte antigen (HLA) antibody production at all the time points. Multivariable analysis showed that nephrectomy was a strong, independent risk factor for the development of DSAs after 12 and 24 months (P = 0.005 and 0.008). In the NX- group, low tacrolimus levels correlated with DSA formation (AUC 0.817, P = 0.002; best cut-off level 2.9 ng/ml). Analysis with a standardized pool of UK donors showed a more difficult grade of HLA matchability following nephrectomy compared with the NX- group. Nephrectomy is followed by the long-term production of DSA and non-DSA HLA antibodies and negatively impacts on the chances of finding a HLA-compatible kidney. Tacrolimus levels ≥3 ng/ml are protective against the development of allosensitization and could facilitate re-transplantation in the NX- group.

How to improve duration and efficiency of the antiproteinuric response to Ramipril: RamiPROT-a prospective cohort study.

BACKGROUND: The antiproteinuric pharmacokinetics of Ramipril in response to different doses and modalities of administration has been poorly investigated so far. STUDY DESIGN: Prospective, open-label and not placebo controlled study. SETTING AND PARTICIPANTS: 40 Caucasian adult patients having GFR ≥ 50 mL/min, proteinuria 1-3 g/day; SBP/DBP ≤ 150/90 mmHg were recruited between June 2014 and November 2014. FACTOR AND OUTCOME: Impact on 24 h proteinuria and fractioned proteinuria of Ramipril given at different dosages (2.5 mg/day or Ramipril 5 mg/day or Ramipril 10 mg/day) and with different daily administration modalities (single or two divided doses) for cycles of 10 days. MEASUREMENTS: At the end of each cycle, 24 h and fractioned proteinuria on three timed urinary collections (morning, afternoon and night) were measured. RESULTS: Compared to baseline, Ramipril significantly reduced 24 h proteinuria at each dose and modality of administration. In particular, the greatest effects were evident with the higher and divided dose of the drug. The analysis of the fractioned proteinuria showed that the greatest reduction was obtained in the night urinary collection by administering Ramipril 10 mg/day in two divided doses. LIMITATIONS: Small sample size. CONCLUSIONS: Ramipril reduces proteinuria at any of the tested doses. Although the using of high and divided doses seems to maximize the antiproteinuric effect of the drug, possibly due to a better pharmacological coverage of the nocturnal period.

Exercise in Patients on Dialysis: A Multicenter, Randomized Clinical Trial.

Previous studies have suggested the benefits of physical exercise for patients on dialysis. We conducted the Exercise Introduction to Enhance Performance in Dialysis trial, a 6-month randomized, multicenter trial to test whether a simple, personalized walking exercise program at home, managed by dialysis staff, improves functional status in adult patients on dialysis. The main study outcomes included change in physical performance at 6 months, assessed by the 6-minute walking test and the five times sit-to-stand test, and in quality of life, assessed by the Kidney Disease Quality of Life Short Form (KDQOL-SF) questionnaire. We randomized 296 patients to normal physical activity (control; n=145) or walking exercise (n=151); 227 patients (exercise n=104; control n=123) repeated the 6-month evaluations. The distance covered during the 6-minute walking test improved in the exercise group (mean distance±SD: baseline, 328±96 m; 6 months, 367±113 m) but not in the control group (baseline, 321±107 m; 6 months, 324±116 m; P<0.001 between groups). Similarly, the five times sit-to-stand test time improved in the exercise group (mean time±SD: baseline, 20.5±6.0 seconds; 6 months, 18.2±5.7 seconds) but not in the control group (baseline, 20.9±5.8 seconds; 6 months, 20.2±6.4 seconds; P=0.001 between groups). The cognitive function score (P=0.04) and quality of social interaction score (P=0.01) in the kidney disease component of the KDQOL-SF improved significantly in the exercise arm compared with the control arm. Hence, a simple, personalized, home-based, low-intensity exercise program managed by dialysis staff may improve physical performance and quality of life in patients on dialysis.

[Is it feasible to improve the duration and the efficiency of Ramipril anti-proteinuric response?]. / È possibile migliorare la durata e l'efficacia della risposta anti-proteinurica di Ramipril?

BACKGROUND: Ramipril administered once daily is characterized by an attenuation of its pharmacological activity in the following 24 hours, whose effects on antiproteinuric activity have not yet been investigated. METHODS: The antiproteinuric efficacy of Ramipril has been evaluated in a cross-over study in 20 patients with renal disease, proteinuria and hypertension (GFR50 mL / min, proteinuria <3 g / day; SBP/DBP 150/90 mmHg). Proteinuria was measured over 24 hours on three consecutive urine collections (morning, afternoon and night) in the absence of antiproteinuric drugs and after ten days of treatment with single morning administration of Ramipril 2.5 mg or Ramipril 10 mg. RESULTS: At baseline: mean proteinuria was not significantlychanged over the course of the three urinary collections (88 7.2 mg/h in the morning of 80 10.5 mg/h in the afternoon and 81 10.1 mg/hr during the night). After Ramipril 2.5 mg/day: slight reduction in mean proteinuria, with no significant differences between collections (80 11 mg/h in the morning, 69 7.4 mg/h in the afternoon and 75 9.1 mg/h during the night). After Ramipril 10 mg/day: afternoon and night values of proteinuria were significantly reduced compared to baseline; noctural proteinuria was significantly lower than morning value (51 7.5 mg/h vs. 81 10 mg/h, p <0.05). CONCLUSION: The antiproteinuric effectiveness of Ramipril tends to decrease significantly over the 24hours after a single daily administration. An increase and/or division of Ramipril dose might help to stabilize and to maximizeits antiproteinuric effectiveness.

Serum ß-crosslaps as predictor of long-term parathyroid hormone levels in hemodialysis patients.

BACKGROUND AND AIMS: Parathyroid hormone (PTH) measurements in hemodialysis (HD) patients are routinely performed every 3 to 6 months of therapy, which are adjusted in accordance with PTH. However, recent evidences show very high PTH biological variability. The aim of our study was to evaluate the role of serum ß-crosslap (CTX), a validated marker of bone resorption, as indicator of PTH maintenance at different time intervals. METHODS: Forty-six HD patients fulfilled the inclusion criteria (HD age of more than 21 months and 7 PTH measurements for the last 21 months) for this retrospective cohort study and were enrolled. Data of the backward quarter PTH values for the last 21 months were collected from clinical records, and a single CTX was measured.To evaluate the relationship between CTX value and the maintenance of PTH in the short-term and long-term, 7 time intervals (3, 6, 9, 12, 15, 18, and 21 months) were stated and the mean value of PTH was measured within each interval and calculated for every patient. RESULTS: We found the following: (1) positive correlation between mean PTH in each time interval and ß-crosslaps with a progressive increase of the correlation coefficient (highest value for the 12- and 21-month intervals); (2) significant differences between tertiles of ß-crosslaps at 6-, 9-, 12-, 15-, 18-, and 21-month intervals, with a progressively growing value of the test coefficient; and (3) after the computation of receiver operating characteristic curves, ß-crosslaps showed to significantly estimate threshold PTH values with the highest areas under the curves (AUCs; AUC, 0.763; 95% confidence interval, 0.625-0.901 for <150 pg/mL of PTH; AUC, 0.774; 95% confidence interval, 0.614-0.934 for >300 pg/mL of PTH) and best value of both sensitivity and specificity at the 12-month time interval (82% and 72% for <150 pg/mL of PTH; 78% and 79% for >300 pg/mL of PTH). CONCLUSIONS: In HD patients, ß-crosslaps have a potential ability to best estimate backward PTH into 12 months of interval.

Can renal sonography be a reliable diagnostic tool in the assessment of chronic kidney disease?

OBJECTIVES: Kidney size has been found to be correlated with anthropometric features and kidney function. Therefore, we postulate that if the conventionally measured renal sonographic parameters (pole-to-pole length, width, and parenchymal thickness) are taken according to standardized rules and corrected for body height, their association with kidney function could be strengthened, thus helping validate renal sonographic information for a better assessment of chronic kidney disease (CKD) status. METHODS: This cross-sectional study included 72 stable adult patients with stage 1 to 4 CKD. Sonographic parameters were obtained from both kidneys and averaged, and the measurements obtained were further corrected for patients' body height. The glomerular filtration rate (GFR) was estimated by the Chronic Kidney Disease Epidemiology Collaboration equation. RESULTS: Parenchymal thickness and renal length showed the highest correlation level with the GFR. This significant correlation, however, was greatly ameliorated by the correction for patients' body height (r = 0.537; P < .001; r = 0.510; P < .001, respectively). Of note, the product of these two parameters corrected for body height showed the best degree of correlation with the GFR (r = 0.560; P < .001), as confirmed by analysis of variance after subdivision of the population into CKD stage groups according to the GFR. Receiver operating characteristic curve analysis for discrimination of a GFR of less than 60 mL/min indentified the combined parameter as the one with the highest area under the curve (0.78; 95% confidence interval, 0.66-0.89), followed renal length corrected for height (area under the curve, 0.77; 95% confidence interval, 0.66-0.88). CONCLUSIONS: Correction of renal sonographic parameters for body height strengthens the degree of the correlation of renal sonography with the GFR. The improved correlation with the GFR makes renal sonography a reliable tool for a more complete assessment of patients with CKD.

Fitness for entering a simple exercise program and mortality: a study corollary to the exercise introduction to enhance performance in dialysis (EXCITE) trial.

BACKGROUND/AIMS: In this corollary analysis of the EXCITE study, we looked at possible differences in baseline risk factors and mortality between subjects excluded from the trial because non-eligible (n=216) or because eligible but refusing to participate (n=116). METHODS: Baseline characteristics and mortality data were recorded. Survival and independent predictors of mortality were assessed by Kaplan-Meier and Cox regression analyses. RESULTS: The incidence rate of mortality was higher in non-eligible vs. eligible non-randomized patients (21.0 vs. 10.9 deaths/100 persons-year; P<0.001). The crude excess risk of death in non-eligible patients (HR 1.96; 95% CI 1.36 to 2.77; P<0.001) was reduced after adjustment for risk factors which differed in the two cohorts including age, blood pressure, phosphate, CRP, smoking, diabetes, triglycerides, cardiovascular comorbidities and history of neoplasia (HR 1.60; 95% CI 1.10 to 2.35; P=0.017) and almost nullified after including in the same model also information on deambulation impairment (HR 1.16; 95% CI 0.75 to 1.80; P=0.513). CONCLUSIONS: Deambulation ability mostly explains the difference in survival rate in non-eligible and eligible non-randomized patients in the EXCITE trial. Extending data analyses and outcome reporting also to subjects not taking part in a trial may be helpful to assess the representability of the study population.

Physical performance and clinical outcomes in dialysis patients: a secondary analysis of the EXCITE trial.

BACKGROUND/AIMS: Scarce physical activity predicts shorter survival in dialysis patients. However, the relationship between physical (motor) fitness and clinical outcomes has never been tested in these patients. METHODS: We tested the predictive power of an established metric of motor fitness, the Six-Minute Walking Test (6MWT), for death, cardiovascular events and hospitalization in 296 dialysis patients who took part in the trial EXCITE (ClinicalTrials.gov Identifier: NCT01255969). RESULTS: During follow up 69 patients died, 90 had fatal and non-fatal cardiovascular events, 159 were hospitalized and 182 patients had the composite outcome. In multivariate Cox models - including the study allocation arm and classical and non-classical risk factors - an increase of 20 walked metres during the 6MWT was associated to a 6% reduction of the risk for the composite end-point (P=0.001) and a similar relationship existed between the 6MWT, mortality (P<0.001) and hospitalizations (P=0.03). A similar trend was observed for cardiovascular events but this relationship did not reach statistical significance (P=0.09). CONCLUSIONS: Poor physical performance predicts a high risk of mortality, cardiovascular events and hospitalizations in dialysis patients. Future studies, including phase-2 EXCITE, will assess whether improving motor fitness may translate into better clinical outcomes in this high risk population.

Single FGF-23 measurement and time-averaged plasma phosphate levels in hemodialysis patients.

BACKGROUND AND OBJECTIVES: Plasma phosphate levels display considerable intraindividual variability. The phosphatonin fibroblast growth factor 23 is a central regulator of plasma phosphate levels, and it has been postulated to be a more stable marker than conventional CKD-mineral and bone disorder parameters. Thus, fibroblast growth factor 23 has been hypothesized to reflect time-averaged plasma phosphate levels in CKD patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Among 40 patients from the outpatient dialysis center, serial measurements of plasma calcium and phosphate (before every dialysis session) as well as C-terminal fibroblast growth factor 23, parathyroid hormone, and alkaline phosphatase (one time weekly) were performed over a study period of 4 weeks in November and December of 2011. Intraindividual variability of repeated plasma fibroblast growth factor 23 measurements compared with other CKD-mineral and bone disorder markers was tested, and the association of a single plasma fibroblast growth factor 23 measurement with time-averaged plasma phosphate levels was analyzed. RESULTS: Against expectations, intraindividual variability of fibroblast growth factor 23 (median coefficient of variation=27%; interquartile range=20-35) was not lower than variability of plasma phosphate (median coefficient of variation=15%; interquartile range=10-20), parathyroid hormone (median coefficient of variation=24%; interquartile range=15-39), plasma calcium (median coefficient of variation=3%; interquartile range=2-4), or alkaline phosphatase (median coefficient of variation=5%; interquartile range=3-10). Moreover, the correlation between the last fibroblast growth factor 23 measurement after 4 weeks and time-averaged plasma phosphate did not surpass the correlation between the last fibroblast growth factor 23 measurement and a single plasma phosphate value (r=0.67, P<0.001; r=0.76, P<0.001, respectively). CONCLUSIONS: Surprisingly, fibroblast growth factor 23 was not more closely associated to time-averaged plasma phosphate levels than a single plasma phosphate value, and it did not show a lower intraindividual variability than other tested markers of CKD-mineral and bone disorder. Thus, fibroblast growth factor 23 should not be used in clinical practice as a reflector of time-averaged plasma phosphate levels.

An uncommon presentation of an uncommon nephropathy: the karyomegalic interstitial nephritis.

Karyomegalic interstitial nephritis (KIN) is a rare and certainly underdiagnosed nephropathy. It is characterized by a peculiar histological picture of interstitial nephritis associated with the presence of hyperchromatic, abnormally enlarged nuclei of tubular epithelial cells. KIN has an uncertain etiology, but should be suspected in young patients in the second or third decade of life presenting with progressive renal failure, proteinuria and/or hematuria and a history of recurrent respiratory infections. In these cases, the diagnosis should be suspected and confirmed by a renal biopsy. Herein, we report a case of KIN with atypical clinical presentation in a young patient with progressive kidney failure without proteinuria or hematuria or history of recurrent respiratory infections.

Have we new therapeutic strategies in the treatment of renovascular nephropathy?

Renal artery stenosis (RAS) is a cause of hypertension and ischemic nephropathy. The incidence of this disorder is probably less than 1% in patients with mild hypertension, but rises to as high as 10 to 40% in patients with acute, severe or refractory hypertension. Significant RAS can be caused by atheromatous plaques, or due to fibromuscular dysplasia (FMD). Atherosclerotic lesions are present in almost 7% of adults older than 65 years and up to 50% of patients presenting with diffuse atherosclerotic disease. In contrast to atherosclerosis, FMD most often affects women under the age of 50 and typically involves the distal main renal artery or the intrarenal branches. The optimal treatment for RAS is not yet established. Based on recent trials, we reviewed the literature on pharmacological and endovascular treatment of atherosclerotic RAS and ischemic nephropathy.

Ultrasound renal resistive index is not an organ-specific predictor of allograft outcome.

BACKGROUND: Ultrasound-measured renal resistive index (RRI) has been suggested to predict allograft survival in renal transplant recipients. Based on experimental and clinical data, we objected to the theory that RRI specifically mirrors allograft characteristics. Instead, we hypothesized that RRI rather represents a marker of systemic vascular damage than an organ-specific marker. In order to refute this hypothesis, RRI should override the resistive index measured in other abdominal parenchymatous organs-such as the spleen-as predictor of allograft outcome. We therefore set out to simultaneously measure renal and splenic ultrasound resistive index in kidney allograft recipients. METHODS: Eighty-seven stable transplant recipients were recruited. We measured RRI, splenic resistive index (SRI) and an established marker of systemic vascular damage, namely common carotid intima-media thickness (IMT). During a follow-up of 4.9 ± 0.5 years, the occurrence of the combined primary end point, defined as a decrease of ≥ 50% in estimated glomerular filtration rate (eGFR), need for dialysis treatment or death, was recorded. RESULTS: At baseline, both RRI and SRI correlated with common carotid IMT [RRI: r = 0.203 (P = 0.006); SRI: r = 0.315 (P < 0.001)], but not with allograft-specific markers such as eGFR or proteinuria. Elevated RRI was a weak non-significant predictor of the combined primary end point. Notably, RRI did not surpass SRI as outcome predictor. When analysing individual components of the combined primary end point separately, elevated RRI failed to predict strictly renal events (decrease of ≥ 50% in eGFR/need for dialysis treatment), while it predicted total mortality. CONCLUSIONS: Our findings support the notion that RRI is not a specific indicator of allograft damage. Similar to SRI, RRI is rather associated with systemic vascular damage markers and mortality.

The kidney and the elderly: why does the risk increase?

Ageing is characterised by a decline in renal function and by a higher susceptibility to renal diseases. This has been defined by Fliser as the "myth of the inexorable decline of renal function with senescence" and is a consequence of multiple factors that predispose to renal damage. These include physiological factors that cannot be modified or treated, and pathological factors that can be treated and, sometimes, prevented; the former are represented by anatomic, molecular, and functional changes that physiologically occur during the ageing process; the latter-by acquired risk factors, whose incidence increases in the elderly, thus predisposing to or aggravating the renal damage. These include increased prevalence of age-related diseases, increased consumption of potentially nephrotoxic drugs, increased necessity of radiological procedures using iodinated contrast media, and increased necessity of major surgery. In this review we analyse these factors and their relevance in increasing the risk of renal damage in the elderly.

Preoperative statins improve recovery of renal function but not by an anti-inflammatory effect: observational study in 69 elderly patients undergoing cardiac surgery.

BACKGROUND: Older subjects, including those with normal renal function, have an increased risk of acute kidney injury. Preoperative statin therapy has been reported to improve renal outcome after cardiac surgery and to reduce inflammatory response to cardiopulmonary bypass. No study has hitherto evaluated whether the positive effect of pretreatment with statins on postoperative renal outcome is due to their positive effect on inflammatory burst in elderly patients undergoing myocardial revascularization using cardiopulmonary bypass. METHODS: Sixty-nine consecutive elderly patients to undergo isolated coronary artery bypass were enrolled and divided in two groups according to preoperative statin therapy (statin group n = 39) or not (no-statin group n = 30). Primary end-points of this study were the incidence of postoperative acute kidney injury defined by Acute Kidney Injury Network (AKIN) criteria, of acute renal failure needing renal replacement therapy, and the rate of complete recovery of kidney function. Secondary outcomes were perioperative changes of inflammatory and anti-inflammatory cytokines (IL-1ß, IL-2, IL-6, IL-8, IL-10 and TNF-α serum level). RESULTS: Incidence of acute kidney injury was similar between the two groups within 2 days after surgery (statin group 18/30 vs. no-statin group 18/39 P = 0.25). However, statin patients showed significantly higher glomerular filtration rate at 10th postoperative day than no-statin patients (statin group 80 ± 31.1 ml/min vs. no-statin group 59.2 ± 29.5 ml/min, P = 0.006). No significant difference in cytokine levels was observed, except for a higher IL-10 release in no-statin group at 24 h after surgery (statin group 130.22 ± 174.37 pg/ml vs. no-statin group 273.422 ± 351.52 pg/ml, P = 0.03). CONCLUSIONS: In elderly patients, preoperative statin treatment allows better recovery of renal function following cardiopulmonary bypass but not by an anti-inflammatory effect.