Secular Trend in GFR Decline in Non-Dialysis CKD Based on Observational Data From Standard of Care Arms of Trials.

RATIONALE & OBJECTIVE: The standard of care (SoC) group of randomized controlled trials (RCTs) is a useful setting to explore the secular trends in kidney disease progression because implementation of best clinical practices is pursued for all patients enrolled in trials. This meta-analysis evaluated the secular trend in the change of glomerular filtration rate (GFR) decline in the SoC arm of RCTs in chronic kidney disease (CKD) published in the last 30 years. STUDY DESIGN: Systematic review and meta-analysis of the SoC arms of RCTs analyzed as an observational study. SETTING & STUDY POPULATIONS: Adult patients with CKD enrolled in the SoC arm of RCTs. SELECTION CRITERIA FOR STUDIES: Phase 3 RCTs evaluating GFR decline as an outcome in SoC arms. DATA EXTRACTION: Two independent reviewers evaluated RCTs for eligibility and extracted relevant data. ANALYTICAL APPROACH: The mean of GFR declines extracted in the SoC arm of selected RCTs were pooled by using a random effects model. Meta-regression analyses were performed to identify factors that may explain heterogeneity. RESULTS: The SoC arms from 92 RCTs were included in the meta-analysis with a total of 32,202 patients. The overall mean GFR decline was-4.00 (95% CI, -4.55 to-3.44) mL/min/1.73m2 per year in the SoC arms with a high level of heterogeneity (I2, 98.4% [95% CI, 98.2-98.5], P<0.001). Meta-regression analysis showed an association between publication year (ß estimate, 0.09 [95% CI, 0.032-0.148], P=0.003) and reduction in GFR over time. When evaluating publication decade categorically, GFR decline was-5.44 (95% CI, -7.15 to-3.73), -3.92 (95% CI, -4.82 to-3.02), and -3.20 (95% CI, -3.75 to -2.64) mL/min/1.73m2 per year during 1991-2000, 2001-2010, and 2011-2023, respectively. Using meta-regression, the heterogeneity of GFR decline was mainly explained by age and proteinuria. LIMITATIONS: Different methods assessing GFR in selected trials and observational design of the study. CONCLUSIONS: In the last 3 decades, GFR decline has decreased over time in patients enrolled in RCTs who received the standard of care. TRIAL REGISTRATION: Registered at PROSPERO with record number CRD42022357704. PLAIN-LANGUAGE SUMMARY: This study evaluated the secular trend in the change in glomerular filtration rate (GFR) decline in the placebo arms of randomized controlled trials (RCTs) that were studying approaches to protect the kidneys in the setting of chronic kidney disease. The placebo groups of RCTs are useful for examining whether the rate of progression of kidney disease has changed over time. We found an improvement in the slope of change in GFR over time. These findings suggest that adherence to standards of kidney care as implemented in clinical trials may be associated with improved clinical outcomes, and these data may inform the design of future RCTs in nephrology.

Dipping Status, Ambulatory Blood Pressure Control, Cardiovascular Disease, and Kidney Disease Progression: A Multicenter Cohort Study of CKD.

RATIONALE & OBJECTIVE: Ambulatory blood pressure (BP) monitoring allows concurrent evaluation of BP control and nocturnal BP dipping status, both related to adverse outcomes. However, few studies have assessed the prognostic role of combining information on dipping status and achieved ambulatory BP in patients with chronic kidney disease (CKD). STUDY DESIGN: Prospective observational cohort study. SETTING & PARTICIPANTS: 906 patients with hypertension and CKD attending 1 of 3 Italian nephrology clinics. EXPOSURE: Four groups were defined by simultaneously classifying systolic ambulatory BP levels as being at goal (daytime SBP <135 and nighttime SBP <120 mm Hg) or above goal, and the presence or absence of nocturnal dipping (nighttime to daytime SBP ratio of <0.9 versus ≥0.9). OUTCOME: The composite of time to initiation of maintenance dialysis or estimated glomerular filtration rate (eGFR) decline ≥50%, and the composite of fatal and nonfatal cardiovascular events. ANALYTICAL APPROACH: Multivariable Cox proportional hazards models were used to estimate risks of kidney disease progression and cardiovascular disease in the 4 exposure groups where nocturnal dipping with systolic ambulatory BP at goal was the reference group. RESULTS: The mean patient age was 63.8 years, 61% were male, and 26.4% had diabetes; eGFR was 41.1 ± 20.8 mL/min/1.73 m2. The dipping prevalence in each of the 4 groups was as follows: nocturnal dipping with ambulatory BP at goal, 18.6%; no nocturnal dipping with ambulatory BP at goal, 20.5%; nocturnal dipping with ambulatory BP above goal, 11.8%; and no nocturnal dipping with ambulatory BP above goal, 49.1%. Among patients with ambulatory BP above goal, the risk of cardiovascular events was greater in the absence (HR, 2.79 [95% CI, 1.64-4.75]) and presence (HR, 2.05 [95% CI, 1.10-3.84]) of nocturnal dipping. The same held true for risk of kidney disease progression (HRs of 2.40 [95% CI, 1.58-3.65] and 2.11 [95% CI, 1.28-3.48] in the absence and presence of nocturnal dipping, respectively). Patients at the ambulatory BP goal but who did not experience nocturnal dipping had an increased risk of the cardiovascular end point (HR, 2.06 [95% CI, 1.15-3.68]) and the kidney disease progression outcome (HR, 1.82 [95% CI, 1.17-2.82]). LIMITATIONS: Lack of a diverse cohort (all those enrolled were White). Residual uncontrolled confounding. CONCLUSIONS: Systolic ambulatory BP above goal or the absence of nocturnal dipping, regardless of ambulatory BP, is associated with higher risks of cardiovascular disease and kidney disease progression among patients with CKD. PLAIN-LANGUAGE SUMMARY: Among patients with chronic kidney disease (CKD), ambulatory blood pressure (BP) monitoring improves the identification of individuals at high risk of clinical disease outcomes. Those with uncontrolled ambulatory BP are known to have a higher risk of developing cardiovascular disease and kidney disease progression, particularly when their ambulatory BP does not decline by at least 10% at night. Whether this is also true for patients with presence of optimal ambulatory BP levels but a BP pattern of no nighttime decline is largely unknown. We measured ambulatory BP in 900 Italian patients with CKD and followed them for several years. We found that, independent of ambulatory BP level, the absence of nighttime reductions in BP was associated with worsening of CKD and more frequent cardiovascular events. The absence of nighttime declines in BP is an independent risk factor for adverse events among patients with CKD. Future studies are needed to examine whether treating the absence of nighttime declines in BP improves clinical outcomes.

Sex difference in cardiovascular risk in patients with chronic kidney disease: pooled analysis of four cohort studies.

BACKGROUND: Progression of chronic kidney disease (CKD) has proven to be faster in men than in women. Whether the same holds true for cardiovascular risk remains ill-defined. METHODS: We conducted a pooled analysis of 4 cohort studies from 40 nephrology clinics in Italy including patients with CKD (estimated GFR<60 ml/min/1.73m2 or higher if proteinuria > 0.15 g/day). The aim was to compare multivariable-adjusted risk (Hazard Ratio, 95% Confidence Interval) of a composite cardiovascular endpoint (cardiovascular death and non-fatal myocardial infarction, congestive heart failure, stroke, revascularization, peripheral vascular disease, and non-traumatic amputation) in women (n = 1 192) versus men (n = 1 635). RESULTS: At baseline, women had slightly higher systolic blood pressure (SBP) as compared with men (139±19 vs 138±18 mmHg, P = 0.049), lower eGFR (33.4 vs 35.7 mL/min/1.73 m2, P = 0.001) and lower urine protein excretion (0.30 g/day vs 0.45 g/day in men, P < 0.001). Women did not differ from men in age and prevalence of diabetes while having a lower prevalence of cardiovascular disease, left ventricular hypertrophy and smoking habit. During a median follow-up of 4.0 years, 517 fatal and non-fatal cardiovascular events were registered (199 in women and 318 in men). The adjusted risk of cardiovascular events was lower in women (0.73, 0.60-0.89, P = 0.002) than in men; however, the cardiovascular risk advantage of women progressively diminished as SBP (as continuous variable) increased (P for interaction = 0.021). Similar results were obtained when considering SBP categories; when compared to men, women had lower cardiovascular risk for SBP <130 mmHg (0.50, 0.31-0.80; P = 0.004) and between 130-140 mmHg (0.72, 0.53-0.99; P = 0.038), while no difference was observed for SBP>140 mmHg (0.85, 0.64-1.11; P = 0.232). CONCLUSIONS: Higher BP levels abolish the cardiovascular protection seen in female vs male patients with overt CKD. This finding supports the need for higher awareness of hypertensive burden in women with CKD.

Risk of end-stage kidney disease in kidney transplant recipients versus patients with native chronic kidney disease: multicentre unmatched and propensity-score matched analyses.

BACKGROUND: In kidney transplant recipients (KTR), the end-stage kidney disease (ESKD) risk dependent on the risk factors acting in native chronic kidney disease (CKD) remains undefined. METHODS: We compared risk and determinants of ESKD between 757 adult KTR and 1940 patients with native CKD before and after propensity-score (PS) analysis matched for unmodifiable risk factors [(age, sex, diabetes, cardiovascular disease and estimated glomerular filtration rate (eGFR)]. RESULTS: In unmatched cohorts, eGFR was lower in CKD versus KTR (45.9 ± 11.3 versus 59.2 ± 13.4 mL/min/1.73 m2, P < 0.001). During a median follow-up of 5.4 years, the unadjusted cumulative incidence of ESKD was consistently lower in unmatched KTR versus CKD. Conversely, in PS-matched analysis, the risk of ESKD in KTR was 78% lower versus CKD at 1 year of follow-up while progressively increased over time resulting similar to that of native CKD patients after 5 years and 2.3-fold higher than that observed in CKD at 10 years. R2 analysis in unmatched patients showed that the proportion of the outcome variance explained by traditional ESKD determinants was smaller in KTR versus native CKD (31% versus 70%). After PS matching, the risk of ESKD [hazard ratio (HR), 95% confidence interval (95% CI)] was significantly associated with systolic blood pressure (1.02, 1.01-1.02), phosphorus (1.31, 1.05-1.64), 24-h proteinuria (1.11, 1.05-1.17) and haemoglobin (0.85, 0.78-0.93) irrespective of KTR status. Similar data were obtained after matching also for modifiable risk factors. CONCLUSIONS: In KTR, when compared with matched native CKD patients, the risk of ESKD is lower in the first 5 years and higher later on. Traditional determinants of ESKD account for one-third of the variability of time-to-graft failure.

The number of risk factors not at target is associated with cardiovascular risk in a type 2 diabetic population with albuminuria in primary cardiovascular prevention. Post-hoc analysis of the NID-2 trial.

BACKGROUND: Nephropathy in Diabetes type 2 (NID-2) study is an open-label cluster randomized clinical trial that demonstrated that multifactorial intensive treatment reduces Major Adverse Cardiac Events (MACEs) and overall mortality versus standard of care in type 2 diabetic subjects with albuminuria and no history of cardiovascular disease. Aim of the present post-hoc analysis of NID- 2 study is to evaluate whether the number of risk factors on target associates with patient outcomes. METHODS: Intervention phase lasted four years and subsequent follow up for survival lasted 10 years. To the aim of this post-hoc analysis, the whole population has been divided into 3 risk groups: 0-1 risk factor (absent/low); 2-3 risk factors (intermediate); 4 risk factors (high). Primary endpoint was a composite of fatal and non-fatal MACEs, the secondary endpoint was all-cause death at the end of the follow-up phase. RESULTS: Absent/low risk group included 166 patients (52.4%), intermediate risk group 128 (40.4%) and high-risk group 23 (7.3%). Cox model showed a significant higher risk of MACE and death in the high-risk group after adjustment for confounding variables, including treatment arm (HR 1.91, 95% CI 1.04-3.52, P = 0.038 and 1.96, 95%CI 1.02-3.8, P = 0,045, respectively, vs absent/low risk group). CONCLUSIONS: This post-hoc analysis of the NID-2 trial indicates that the increase in the number of risk factors at target correlates with better cardiovascular-free survival in patients with type 2 diabetes at high CV risk. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov number, NCT00535925. https://clinicaltrials.gov/ct2/show/NCT00535925.

Chronic Hyperkaliemia in Chronic Kidney Disease: An Old Concern with New Answers.

Increasing potassium intake ameliorates blood pressure (BP) and cardiovascular (CV) prognoses in the general population; therefore the World Health Organization recommends a high-potassium diet (90-120 mEq/day). Hyperkalaemia is a rare condition in healthy individuals due to the ability of the kidneys to effectively excrete dietary potassium load in urine, while an increase in serum K+ is prevalent in patients with chronic kidney disease (CKD). Hyperkalaemia prevalence increases in more advanced CKD stages, and is associated with a poor prognosis. This scenario generates controversy on the correct nutritional approach to hyperkalaemia in CKD patients, considering the unproven link between potassium intake and serum K+ levels. Another concern is that drug-induced hyperkalaemia leads to the down-titration or withdrawal of renin-angiotensin system inhibitors (RASI) and mineralocorticoids receptors antagonists (MRA) in patients with CKD, depriving these patients of central therapeutic interventions aimed at delaying CKD progression and decreasing CV mortality. The new K+-binder drugs (Patiromer and Sodium-Zirconium Cyclosilicate) have proven to be adequate and safe therapeutic options to control serum K+ in CKD patients, enabling RASI and MRA therapy, and possibly, a more liberal intake of fruit and vegetables.

Efficacy and durability of multifactorial intervention on mortality and MACEs: a randomized clinical trial in type-2 diabetic kidney disease.

BACKGROUND: Multiple modifiable risk factors for late complications in patients with diabetic kidney disease (DKD), including hyperglycemia, hypertension and dyslipidemia, increase the risk of a poor outcome. DKD is associated with a very high cardiovascular risk, which requires simultaneous treatment of these risk factors by implementing an intensified multifactorial treatment approach. However, the efficacy of a multifactorial intervention on major fatal/non-fatal cardiovascular events (MACEs) in DKD patients has been poorly investigated. METHODS: Nephropathy in Diabetes type 2 (NID-2) study is a multicentre, cluster-randomized, open-label clinical trial enrolling 395 DKD patients with albuminuria, diabetic retinopathy (DR) and negative history of CV events in 14 Italian diabetology clinics. Centres were randomly assigned to either Standard-of-Care (SoC) (n = 188) or multifactorial intensive therapy (MT, n = 207) of main cardiovascular risk factors (blood pressure < 130/80 mmHg, glycated haemoglobin < 7%, LDL, HDL and total cholesterol < 100 mg/dL, > 40/50 mg/dL for men/women and < 175 mg/dL, respectively). Primary endpoint was MACEs occurrence by end of follow-up phase. Secondary endpoints included single components of primary endpoint and all-cause death. RESULTS: At the end of intervention period (median 3.84 and 3.40 years in MT and SoC group, respectively), targets achievement was significantly higher in MT. During 13.0 years (IQR 12.4-13.3) of follow-up, 262 MACEs were recorded (116 in MT vs. 146 in SoC). The adjusted Cox shared-frailty model demonstrated 53% lower risk of MACEs in MT arm (adjusted HR 0.47, 95%CI 0.30-0.74, P = 0.001). Similarly, all-cause death risk was 47% lower (adjusted HR 0.53, 95%CI 0.29-0.93, P = 0.027). CONCLUSION: MT induces a remarkable benefit on the risk of MACEs and mortality in high-risk DKD patients. Clinical Trial Registration ClinicalTrials.gov number, NCT00535925. https://clinicaltrials.gov/ct2/show/NCT00535925.

Are all erythropoiesis-stimulating agents created equal?

Erythropoiesis-stimulating agents (ESAs) are effective drugs to correct and maintain haemoglobin (Hb) levels, however, their use at doses to reach high Hb targets has been associated with an increased risk of cardiovascular adverse events, mortality and cancer. Presently used ESAs have a common mechanism of action but different pharmacokinetic and pharmacodynamic characteristics. Accordingly, the mode of activation of the erythropoietin (EPO) receptor can exert marked differences in downstream events. It is unknown whether the various ESA molecules have different efficacy/safety profiles. The relative mortality and morbidity risks associated with the use of different types of ESAs remains poorly evaluated. Recently an observational study and a randomized clinical trial provided conflicting results regarding this matter. However, these two studies displayed several differences in patient characteristics and ESA molecules used. More importantly, by definition, randomized clinical trials avoid bias by indication and suffer less from confounding factors. Therefore they bring a higher degree of evidence. The scenario becomes even more complex when considering the new class of ESAs, called prolyl-hydroxylase domain (PHD) inhibitors. They are oral drugs that mimic exposure to hypoxia and stabilize hypoxia-inducible factor α. They profoundly differ from presently used ESAs, as they have multiple targets of action, including the stimulation of endogenous EPO synthesis, direct mobilization/absorption of iron and a higher reduction of hepcidin. Accordingly, they have the potential to be more effective in inflamed patients with functional iron deficiency, i.e. the setting of patients who are at higher risk of cardiovascular events and mortality in response to present ESA use. As for ESAs, individual PHD inhibitors differ in molecular structure and degree of selectivity for the three main PHD isoforms; their efficacy and safety profiles may therefore be different from that of presently available ESAs.

Types of erythropoiesis-stimulating agents and risk of end-stage kidney disease and death in patients with non-dialysis chronic kidney disease.

BACKGROUND: Despite the widespread use of erythropoiesis-stimulating agents (ESAs) to treat anaemia, the risk of adverse outcomes associated with the use of different types of ESAs in non-dialysis chronic kidney disease (CKD) is poorly investigated. METHODS: From a pooled cohort of four observational studies, we selected CKD patients receiving short-acting (epoetin α/ß; n = 299) or long-acting ESAs (darbepoetin and methoxy polyethylene glycol-epoetin ß; n = 403). The primary composite endpoint was end-stage kidney disease (ESKD; dialysis or transplantation) or all-cause death. Multivariable Cox models were used to estimate the relative risk of the primary endpoint between short- and long-acting ESA users. RESULTS: During follow-up [median 3.6 years (interquartile range 2.1-6.3)], the primary endpoint was registered in 401 patients [166 (72%) in the short-acting ESA group and 235 (58%) in the long-acting ESA group]. In the highest tertile of short-acting ESA dose, the adjusted risk of primary endpoint was 2-fold higher {hazard ratio [HR] 2.07 [95% confidence interval (CI) 1.37-3.12]} than in the lowest tertile, whereas it did not change across tertiles of dose for long-acting ESA patients. Furthermore, the comparison of ESA type in each tertile of ESA dose disclosed a significant difference only in the highest tertile, where the risk of the primary endpoint was significantly higher in patients receiving short-acting ESAs [HR 1.56 (95% CI 1.09-2.24); P = 0.016]. Results were confirmed when ESA dose was analysed as continuous variable with a significant difference in the primary endpoint between short- and long-acting ESAs for doses >105 IU/kg/week. CONCLUSIONS: Among non-dialysis CKD patients, the use of a short-acting ESA may be associated with an increased risk of ESKD or death versus long-acting ESAs when higher ESA doses are prescribed.

Sex difference in ambulatory blood pressure control associates with risk of ESKD and death in CKD patients receiving stable nephrology care.

BACKGROUND: It is unknown whether faster progression of chronic kidney disease (CKD) in men than in women relates to differences in ambulatory blood pressure (ABP) levels. METHODS: We prospectively evaluated 906 hypertensive CKD patients (553 men) regularly followed in renal clinics to compare men versus women in terms of ABP control [daytime <135/85 and nighttime blood pressure (BP) <120/70 mmHg] and risk of all-cause mortality and end-stage kidney disease (ESKD). RESULTS: Age, estimated glomerular filtration rate and use of renin-angiotensin system inhibitors were similar in men and women, while proteinuria was lower in women [0.30 g/24 h interquartile range (IQR) 0.10-1.00 versus 0.42 g/24 h, IQR 0.10-1.28, P = 0.025]. No sex-difference was detected in office BP levels; conversely, daytime and nighttime BP were higher in men (134 ± 17/78 ± 11 and 127 ± 19/70 ± 11 mmHg) than in women (131 ± 16/75 ± 11, P = 0.005/P < 0.001 and 123 ± 20/67 ± 12, P = 0.006/P < 0.001), with ABP goal achieved more frequently in women (39.1% versus 25.1%, P < 0.001). During a median follow-up of 10.7 years, 275 patients reached ESKD (60.7% men) and 245 died (62.4% men). Risks of ESKD and mortality (hazard ratio and 95% confidence interval), adjusted for demographic and clinical variables, were higher in men (1.34, 1.02-1.76 and 1.36, 1.02-1.83, respectively). Adjustment for office BP at goal did not modify this association. In contrast, adjustment for ABP at goal attenuated the increased risk in men for ESKD (1.29, 0.98-1.70) and death (1.31, 0.98-1.77). In the fully adjusted model, ABP at goal was associated with reduced risk of ESKD (0.49, 0.34-0.70) and death (0.59, 0.43-0.80). No interaction between sex and ABP at goal on the risk of ESKD and death was found, suggesting that ABP-driven risks are consistent in males and females. CONCLUSIONS: Our study highlights that higher ABP significantly contributes to higher risks of ESKD and mortality in men.

Volume-Independent Sodium Toxicity in Peritoneal Dialysis: New Insights from Bench to Bed.

Sodium overload is common in end-stage kidney disease (ESKD) and is associated with increased cardiovascular mortality that is traditionally considered a result of extracellular volume expansion. Recently, sodium storage was detected by Na23 magnetic resonance imaging in the interstitial tissue of the skin and other tissues. This amount of sodium is osmotically active, regulated by immune cells and the lymphatic system, escapes renal control, and, more importantly, is associated with salt-sensitive hypertension. In chronic kidney disease, the interstitial sodium storage increases as the glomerular filtration rate declines and is related to cardiovascular damage, regardless of the fluid overload. This sodium accumulation in the interstitial tissues becomes more significant in ESKD, especially in older and African American patients. The possible negative effects of interstitial sodium are still under study, though a higher sodium intake might induce abnormal structural and functional changes in the peritoneal wall. Interestingly, sodium stored in the interstial tissue is not unmodifiable, since it is removable by dialysis. Nevertheless, the sodium removal by peritoneal dialysis (PD) remains challenging, and new PD solutions are desirable. In this narrative review, we carried out an update on the pathophysiological mechanisms of volume-independent sodium toxicity and possible future strategies to improve sodium removal by PD.

Sex Differences in the Progression of CKD Among Older Patients: Pooled Analysis of 4 Cohort Studies.

RATIONALE & OBJECTIVE: Data for the association of sex with chronic kidney disease (CKD) progression are conflicting, a relationship this study sought to examine. STUDY DESIGN: Pooled analysis of 4 Italian observational cohort studies. SETTING & PARTICIPANTS: 1,311 older men and 1,024 older women with estimated glomerular filtration rate (eGFR)<45mL/min/1.73m2 followed up in renal clinics. PREDICTOR: Sex. OUTCOMES: End-stage kidney disease (ESKD), defined as maintenance dialysis or kidney transplantation, as the primary outcome; all-cause mortality and eGFR decline as secondary outcomes. ANALYTICAL APPROACH: Cox proportional hazard analysis to estimate the relative risk for ESKD and mortality and linear mixed models to estimate the rate of eGFR decline. RESULTS: Age, systolic blood pressure, and use of renin-angiotensin system inhibitors were similar in men and women. Baseline eGFRs were 27.6±10.2 in men and 26.0±10.6mL/min/1.73m2 in women (P<0.001), while median proteinuria was lower in women (protein excretion, 0.45 [IQR, 0.14-1.10] g/d) compared with men (0.69 [IQR 0.19-1.60] g/d; P<0.001). During a median follow-up of 4.2 years, 757 developed ESKD (59.4% men) and 471 died (58.4% men). The adjusted risks for ESKD and mortality were higher in men (HRs of 1.50 [95% CI, 1.28-1.77] and 1.30 [95% CI, 1.06-1.60], respectively). This finding was consistent across CKD stages. We observed a significant interaction between sex and proteinuria, with the risk for ESKD in men being significantly greater than for women at a level of proteinuria of ∼0.5g/d or greater. The slope of decline in eGFR was steeper in men (-2.09; 95% CI, -2.21 to-1.97mL/min/1.73m2 per year) than in women (-1.79; 95% CI, -1.92 to-1.66mL/min/1.73m2 per year; P<0.001). Although sex differences in eGFR decline were not different across CKD stages (P=0.3), the difference in slopes between men and women was progressively larger with proteinuria >0.5g/d (P = 0.04). LIMITATIONS: Residual confounding; only whites were included. CONCLUSIONS: Excess renal risk in men may, at least in part, be related to higher levels of proteinuria in men compared with women.

Reclassification of chronic kidney disease patients for end-stage renal disease risk by proteinuria indexed to estimated glomerular filtration rate: multicentre prospective study in nephrology clinics.

BACKGROUND: In non-dialysis chronic kidney disease (CKD), absolute proteinuria (Uprot) depends on the extent of kidney damage and residual glomerular filtration rate (GFR). We therefore evaluated, as compared with Uprot, the strength of association of proteinuria indexed to estimated GFR (eGFR) with end-stage renal disease (ESRD) risk. METHODS: In a multi-cohort prospective study in 3957 CKD patients of Stages G3-G5 referred to nephrology clinics, we tested two multivariable Cox models for ESRD risk, with either Uprot (g/24 h) or filtration-adjusted proteinuria (F-Uprot) calculated as Uprot/eGFR ×100. RESULTS: Mean ± SD age was 67 ± 14 years, males 60%, diabetics 29%, cardiovascular disease (CVD) 34%, eGFR 32 ± 13 mL/min/1.73 m2, median (interquartile range) Uprot 0.41 (0.12-1.29) g/24 h and F-Uprot 1.41 (0.36-4.93) g/24 h per 100 mL/min/1.73 m2 eGFR. Over a median follow-up of 44 months, 862 patients reached ESRD. At competing risk analysis, ESRD risk progressively increased when F-Uprot was 1.0-4.9 and ≥5.0 versus <1.0 g/24 h per 100 mL/min/1.73 m2 eGFR in Stages G3a-G4 (P < 0.001) and Stage G5 (P = 0.002). Multivariable Cox analysis showed that Uprot predicts ESRD in Stages G3a-G4 while in G5 the effect was not significant; conversely, F-Uprot significantly predicted ESRD at all stages. The F-Uprot model allowed a significantly better prediction versus the Uprot model according to Akaike information criterion. Net reclassification improvement was 12.2% (95% confidence interval 4.2-21.1), with higher reclassification in elderly, diabetes and CVD, as well as in diabetic nephropathy and glomerulonephritis, and in CKD Stages G4 and G5. CONCLUSIONS: In patients referred to nephrology clinics, F-Uprot predicts ESRD at all stages of overt CKD and improves, as compared with Uprot, reclassification of patients for renal risk, especially in more advanced and complicated disease.

Cost-analysis of persistent hyperkalaemia in non-dialysis chronic kidney disease patients under nephrology care in Italy.

AIM: In patients with chronic kidney disease (CKD), hyperkalaemia (HK) (potassium level ≥ 5.0 mEq/L) is associated with poor clinical outcomes. This study provides novel insights by comparing management costs of CKD patients with normokalaemia vs those with persistent HK regularly followed in renal clinics in Italy. METHODS: To this aim, a Markov model over life-time horizon was developed. Time to end-stage renal disease (ESRD) and time to death in CKD patients were derived from an observational multi-centre database including 1665 patients with non-dialysis CKD stage 1-5 under nephrology care in Italy (15 years follow-up). Resource use for CKD and HK management was obtained from the observational database, KDIGO international guidelines, and clinical expert opinion. RESULTS: Results showed that patients with normokalaemia vs persistent HK brought an average per patient lifetime cost-saving of €16 059 besides delayed onset of ESRD by 2.29 years and increased survival by 1.79 years with increment in total survival and dialysis-free survival in normokalaemia that decreased from early to advanced disease. Cost-saving related to normokalaemia increased at more advanced CKD; however, it was already evident at early stage (3388.97€ at stage 1-3a). OWSA confirmed cost-saving associated with normokalaemia across all parameter variations. DISCUSSION AND CONCLUSION: This model is the first to simulate the impact of HK in non-dialysis CKD patients on economic and clinical outcomes using real-world data from nephrology clinics. In these patients, persistent HK results into higher lifetime costs, besides poorer clinical outcomes, that are evident since the early stages of CKD. Maintaining normokalaemia should therefore be of main concern in CKD treatment planning to improve long-term economic and clinical outcomes.

Management of hepatitis C virus infection in patients with chronic kidney disease: position statement of the joint committee of Italian association for the study of the liver (AISF), Italian society of internal medicine (SIMI), Italian society of infectious and tropical disease (SIMIT) and Italian society of nephrology (SIN).

Hepatitis C virus (HCV) infection is now considered a systemic disease due to the occurrence of extra-hepatic manifestations. Among these, the renal involvement is frequent. HCV infection, in fact, is strongly associated with proteinuria and chronic kidney disease (CKD) and negatively affects the prognosis of renal patients. In the last few years, availability of more specific and effective drugs against HCV has dramatically changed the clinical course of this disease. These drugs may provide further advantages in the CKD population as a whole by reducing progression of renal disease, mortality rate and by increasing the survival of graft in renal transplant recipients. The strict pathogenetic and prognostic link between HCV infection and CKD requires an ongoing relationship among the healthcare professionals involved in the treatment of both HCV infection and CKD. Therefore, Scientific Societies involved in the care of this high-risk population in Italy have organized a joint expert panel. The aim of the panel is to produce a position statement that can be used in daily clinical practice for the management of HCV infected patients across the whole spectrum of renal disease, from the conservative phase to renal replacement treatments (dialysis and transplantation). Sharing specific evidence-based expertise of different professional healthcare is the first step to obtain a common ground of knowledge on which to instate a model for multidisciplinary management of this high-risk population. Statements cover seven areas including epidemiology of CKD, HCV-induced glomerular damage, HCV-related renal risk, staging of liver disease in patients with CKD, prevention of transmission of HCV in hemodialysis units, treatment of HCV infection and management of HCV in kidney transplantation.

Effect of Increased Convection Volume by Mid-Dilution Hemodiafiltration on the Subclinical Chronic Inflammation in Maintenance Hemodialysis Patients.

Mid-dilution hemodiafiltration (MID) is a dialytic technique that might improve systemic inflammation of patients in chronic hemodialysis (HD) by increasing substitution volumes. To verify this hypothesis, we performed a prospective cross-over study comparing the effect on inflammatory biomarkers of higher convection by MID versus standard convection by post-dilution hemodiafiltration (HDF). Patients under chronic HD were therefore treated by MID and HDF by crossover design. Each treatment period lasted 4 months, with 1 month of wash-out where patients were treated by HD, for a total of 9 months. Primary outcome was the change of serum pre-dialytic C-Reactive Protein (CRP), interleukin 6 (IL-6), IL-1, IL-10, transforming growth factor-ß (TGF-ß), tumor necrosis factor-α, albumin and pre-albumin. Samples were obtained monthly. Ten HD patients were enrolled (age: 64.9 ± 12.6 years; 70% males; dialytic vintage: 10.6 [2.7-16.2] years). Mean convection volume was 40.1 ± 2.5 L/session in MID and 20.1 ± 2.6 L/session in HDF. A significant reduction of ß2-Microglobulin was detected as a result of either treatment. In MID, CRP decreased from 11.3 (3.2-31.0) to 3.1 (1.4-14.4) mg/L (p = 0.007), IL-6 from 12.7 (5.0-29.7) to 8.3 (4.4-14.0) pg/mL (p = 0.003), and TGF-ß from 10.6 (7.4-15.6) to 7.4 (5.9-9.3) ng/mL (p = 0.001). A significant reduction of CRP from 8.5 (3.2-31.0) to 4.6 (3.2-31.0) mg/L was also detected in HDF (p = 0.037), whereas no significant reduction of IL-6 (p = 0.147) and TGF-ß (p = 0.094) was found. Percentage reduction of IL-6 correlated with mean convective volume in HDF (R = 0.666; p = 0.036) and in MID (R = 0.760; p = 0.020). Therefore, MID and HDF are associated with an attenuation of inflammatory pattern that is correlated with a high convective volume.

SGLT2 Inhibitors: Nephroprotective Efficacy and Side Effects.

The burden of diabetic kidney disease (DKD) has increased worldwide in the last two decades. Besides the growth of diabetic population, the main contributors to this phenomenon are the absence of novel nephroprotective drugs and the limited efficacy of those currently available, that is, the inhibitors of renin-angiotensin system. Nephroprotection in DKD therefore remains a major unmet need. Three recent trials testing effectiveness of sodium-glucose cotransporter 2 inhibitors (SGLT2-i) have produced great expectations on this therapy by consistently evidencing positive effects on hyperglycemia control, and more importantly, on the cardiovascular outcome of type 2 diabetes mellitus. Notably, these trials also disclosed nephroprotective effects when renal outcomes (glomerular filtration rate and albuminuria) were analyzed as secondary endpoints. On the other hand, the use of SGLT2-i can be potentially associated with some adverse effects. However, the balance between positive and negative effects is in favor of the former. The recent results of Canagliflozin and Renal Endpoints in Diabetes with Established Nephropathy Clinical Evaluation Study and of other trials specifically testing these drugs in the population with chronic kidney disease, either diabetic or non-diabetic, do contribute to further improving our knowledge of these antihyperglycemic drugs. Here, we review the current state of the art of SGLT2-i by addressing all aspects of therapy, from the pathophysiological basis to clinical effectiveness.

Different rates of progression and mortality in patients with chronic kidney disease at outpatient nephrology clinics across Europe.

The incidence of renal replacement therapy varies across countries. However, little is known about the epidemiology of chronic kidney disease (CKD) outcomes. Here we describe progression and mortality risk of patients with CKD but not on renal replacement therapy at outpatient nephrology clinics across Europe using individual data from nine CKD cohorts participating in the European CKD Burden Consortium. A joint model assessed the mean change in estimated glomerular filtration rate (eGFR) and mortality risk simultaneously, thereby accounting for mortality risk when estimating eGFR decline and vice versa, while also correcting for the measurement error in eGFR. Results were adjusted for important risk factors (baseline eGFR, age, sex, albuminuria, primary renal disease, diabetes, hypertension, obesity and smoking) in 27,771 patients from five countries. The adjusted mean annual eGFR decline varied from 0.77 (95% confidence interval 0.45, 1.08) ml/min/1.73m2 in the Belgium cohort to 2.43 (2.11, 2.75) ml/min/1.73m2 in the Spanish cohort. As compared to the Italian PIRP cohort, the adjusted mortality hazard ratio varied from 0.22 (0.11, 0.43) in the London LACKABO cohort to 1.30 (1.13, 1.49) in the English CRISIS cohort. These results suggest that the eGFR decline showed minor variation but mortality showed the most variation. Thus, different health care organization systems are potentially associated with differences in outcome of patients with CKD within Europe. These results can be used by policy makers to plan resources on a regional, national and European level.

Cardiorenal prognosis by residual proteinuria level in diabetic chronic kidney disease: pooled analysis of four cohort studies.

Background: No study has assessed whether the prognosis of coexisting diabetes mellitus and chronic kidney disease (DM-CKD) is dictated by DM per se or by the extent of proteinuria. Methods: In this pooled analysis of four prospective studies in CKD patients treated with drugs inhibiting the renin-angiotensin system, we compared the risk of all-cause mortality, fatal and non-fatal cardiovascular (CV) events and end-stage renal disease (ESRD) between patients with (n = 693) and without diabetes (n = 1481) stratified by proteinuria level (<0.15, 0.15-0.49, 0.5-1 and >1 g/day). Results: The group with DM-CKD was older (69 ± 11 versus 65 ± 15 years), had a higher body mass index (29.6 ± 5.4 versus 27.5 ± 4.8 kg/m2) and systolic blood pressure (143 ± 19 versus 136 ± 18 mmHg), prevalent CV disease (48% versus 29%) and lower estimated glomerular filtration rate (34.5 ± 17.9 versus 36.6 ± 19.0 mL/min/1.73 m2). During 4.07 years of follow-up, there were 466 patients with ESRD, 334 deaths and 401 CV events occurred. In the subgroup with urine protein <0.15 g/day (N = 662), the risks of ESRD, CV events and mortality were similar in diabetic and non-diabetic patients. Conversely, in DM-CKD patients, the mortality risk was higher in proteinuric patients {hazard ratio 1.92 [95% confidence interval (CI) 1.25-2.95); 1.99 (1.26-3.15) and 1.98 (1.28-3.06) for proteinuria 0.15-0.49, 0.5-1 and >1 g/day, respectively}, whereas in non-diabetics the mortality risk increased only for proteinuria 0.5-1 g/day [HR 1.60 (95% CI 1.07-2.40)] and >1 g/day [HR 1.69 (95% CI1.20-2.55)]. In both groups, CV risk had a trend similar to that of mortality. ESRD risk increased progressively across strata >0.5 g/day independent of diabetic status. Conclusions: We provide evidence that patients with non-proteinuric DM-CKD are not exposed to higher cardiorenal risk. In contrast, in the presence of moderate proteinuria and diabetes per se is associated with a higher risk of mortality and CV events, whereas the entity of abnormal proteinuria modulates ESRD risk independent of diabetes.

Effect of post-nephrectomy acute kidney injury on renal outcome: a retrospective long-term study.

PURPOSE: The effects on renal prognosis of acute kidney injury after elective unilateral nephrectomy are ill-defined. We evaluated as whether post-operative acute kidney injury modifies renal outcome over the long term. METHODS: This is a retrospective study examining all consecutive adult patients referred to three Nephrology Units and that had previously undergone elective unilateral nephrectomy. We evaluated the association of post-nephrectomy acute kidney injury with the combined renal outcome of chronic dialysis requirement, ≥ 40% decline in glomerular filtration rate or new-onset severe proteinuria (> 500 mg/24 h). Clinical correlates of acute kidney injury and renal outcome were also examined. RESULTS: 106 patients were enrolled. 52 patients had post-operative acute kidney injury with a median increment of serum creatinine of 0.67 [0.48-0.86] mg/dl; in these patients, serum creatinine and urea increased from the first day post-nephrectomy while contraction of urinary output was found in 7 patients. Older age [OR: 1.72; 95% CI 1.05-2.82; P = 0.030] associated with post-operative acute kidney injury. Over a median follow-up of 8.9 [95% CI 3.1-24.2] years, the combined renal outcome occurred, respectively, in 28 (53.8%) and 14 (25.9%) patients with and without acute kidney injury (P = 0.003). Logistic regression analysis showed that acute kidney injury (OR: 3.22; 95% CI 1.35-7.66; P = 0.008) and male gender (OR: 2.72; 95% CI 1.08-6.85; P = 0.034) were associated with poor renal outcome after adjustment for main comorbidities. CONCLUSIONS: In our population of referred patients, acute kidney injury after unilateral nephrectomy was common and associated with progressive chronic kidney disease, especially in older males.