Angiotensin-Converting Enzyme Inhibitors or Angiotensin-Receptor Blockers for Advanced Chronic Kidney Disease : A Systematic Review and Retrospective Individual Participant-Level Meta-analysis of Clinical Trials.

BACKGROUND: In patients with advanced chronic kidney disease (CKD), the effects of initiating treatment with an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin-receptor blocker (ARB) on the risk for kidney failure with replacement therapy (KFRT) and death remain unclear. PURPOSE: To examine the association of ACEi or ARB treatment initiation, relative to a non-ACEi or ARB comparator, with rates of KFRT and death. DATA SOURCES: Ovid Medline and the Chronic Kidney Disease Epidemiology Collaboration Clinical Trials Consortium from 1946 through 31 December 2023. STUDY SELECTION: Completed randomized controlled trials testing either an ACEi or an ARB versus a comparator (placebo or antihypertensive drugs other than ACEi or ARB) that included patients with a baseline estimated glomerular filtration rate (eGFR) below 30 mL/min/1.73 m2. DATA EXTRACTION: The primary outcome was KFRT, and the secondary outcome was death before KFRT. Analyses were done using Cox proportional hazards models according to the intention-to-treat principle. Prespecified subgroup analyses were done according to baseline age (<65 vs. ≥65 years), eGFR (<20 vs. ≥20 mL/min/1.73 m2), albuminuria (urine albumin-creatinine ratio <300 vs. ≥300 mg/g), and history of diabetes. DATA SYNTHESIS: A total of 1739 participants from 18 trials were included, with a mean age of 54.9 years and mean eGFR of 22.2 mL/min/1.73 m2, of whom 624 (35.9%) developed KFRT and 133 (7.6%) died during a median follow-up of 34 months (IQR, 19 to 40 months). Overall, ACEi or ARB treatment initiation led to lower risk for KFRT (adjusted hazard ratio, 0.66 [95% CI, 0.55 to 0.79]) but not death (hazard ratio, 0.86 [CI, 0.58 to 1.28]). There was no statistically significant interaction between ACEi or ARB treatment and age, eGFR, albuminuria, or diabetes (P for interaction > 0.05 for all). LIMITATION: Individual participant-level data for hyperkalemia or acute kidney injury were not available. CONCLUSION: Initiation of ACEi or ARB therapy protects against KFRT, but not death, in people with advanced CKD. PRIMARY FUNDING SOURCE: National Institutes of Health. (PROSPERO: CRD42022307589).

A meta-analysis of randomized controlled clinical trials for implications of acute treatment effects on glomerular filtration rate for long-term kidney protection.

Pharmacologic interventions to slow chronic kidney disease progression, such as ACE-inhibitors, angiotensin receptor blockers, or sodium glucose co-transporter 2 inhibitors, often produce acute treatment effects on glomerular filtration rate (GFR) that differ from their long-term chronic treatment effects. Observational studies assessing the implications of acute effects cannot distinguish acute effects from GFR changes unrelated to the treatment. Here, we performed meta-regression analysis of multiple trials to isolate acute effects to determine their long-term implications. In 64 randomized controlled trials (RCTs), enrolling 154,045 participants, we estimated acute effects as the mean between-group difference in GFR slope from baseline to three months, effects on chronic GFR slope (starting at three months after randomization), and effects on three composite kidney endpoints defined by kidney failure (GFR 15 ml/min/1.73m2 or less, chronic dialysis, or kidney transplantation) or sustained GFR declines of 30%, 40% or 57% decline, respectively. We used Bayesian meta-regression to relate acute effects with treatment effects on chronic slope and the composite kidney endpoints. Overall, acute effects were not associated with treatment effects on chronic slope. Acute effects were associated with the treatment effects on composite kidney outcomes such that larger negative acute effects were associated with lesser beneficial effects on the composite kidney endpoints. Associations were stronger when the kidney composite endpoints were defined by smaller thresholds of GFR decline (30% or 40%). Results were similar in a subgroup of interventions with supposedly hemodynamic effects that acutely reduce GFR. For studies with GFR 60 mL/min/1.73m2 or under, negative acute effects were associated with larger beneficial effects on chronic GFR slope. Thus, our data from a large and diverse set of RCTs suggests that acute effects of interventions may influence the treatment effect on clinical kidney outcomes.

A randomized multicenter trial on a lung ultrasound-guided treatment strategy in patients on chronic hemodialysis with high cardiovascular risk.

Lung congestion is a risk factor for all-cause and cardiovascular mortality in patients on chronic hemodialysis, and its estimation by ultrasound may be useful to guide ultrafiltration and drug therapy in this population. In an international, multi-center randomized controlled trial (NCT02310061) we investigated whether a lung ultrasound-guided treatment strategy improved a composite end point (all-cause death, non-fatal myocardial infarction, decompensated heart failure) vs usual care in patients receiving chronic hemodialysis with high cardiovascular risk. Patient-Reported Outcomes (Depression and the Standard Form 36 Quality of Life Questionnaire, SF36) were assessed as secondary outcomes. A total of 367 patients were enrolled: 183 in the active arm and 180 in the control arm. In the active arm, the pre-dialysis lung scan was used to titrate ultrafiltration during dialysis and drug treatment. Three hundred and seven patients completed the study: 152 in the active arm and 155 in the control arm. During a mean follow-up of 1.49 years, lung congestion was significantly more frequently relieved in the active (78%) than in the control (56%) arm and the intervention was safe. The primary composite end point did not significantly differ between the two study arms (Hazard Ratio 0.88; 95% Confidence Interval: 0.63-1.24). The risk for all-cause and cardiovascular hospitalization and the changes of left ventricular mass and function did not differ among the two groups. A post hoc analysis for recurrent episodes of decompensated heart failure (0.37; 0.15-0.93) and cardiovascular events (0.63; 0.41-0.97) showed a risk reduction for these outcomes in the active arm. There were no differences in patient-reported outcomes between groups. Thus, in patients on chronic hemodialysis with high cardiovascular risk, a treatment strategy guided by lung ultrasound effectively relieved lung congestion but was not more effective than usual care in improving the primary or secondary end points of the trial.

Dialysis dose and mortality in haemodialysis: is higher better?

BACKGROUND: The effect of dialysis dose on mortality remains unsettled. Current guidelines recommend targeting a single-pool Kt/V (spKt/V) at 1.20-1.40 per thrice-weekly dialysis session. However, the optimal dialysis dose remains mostly disputed. METHODS: In a nationwide registry of all incident patients receiving thrice-weekly haemodialysis, 32 283 patients had available data on dialysis dose, estimated by Kt/V and its variants epuration volume per session (Kt) and Kt indexed to body surface area (Kt/A). Survival was analysed with a multivariate Cox model and a concurrent risk model accounting for renal transplantation. A predictive model of Kt in the upper quartile was developed. RESULTS: Regardless of the indicator, a higher dose of dialysis was consistently associated with better survival. The survival differential of Kt was the most discriminating, but marginally, compared with the survival differential according to Kt/V and Kt/A. Patient survival was higher in the upper quartile of Kt (>69 L/session) then deteriorated as the Kt decreased, with a difference in survival between the upper and lower quartile of 23.6% at 5 years. Survival differences across Kt distribution were similar after accounting for kidney transplantation as a competing risk. Predictive factors for Kt in the upper quartile were arteriovenous fistula versus catheters and graft, haemodiafiltration versus haemodialysis, scheduled dialysis start versus emergency start, long weekly dialysis duration and spKt/V measurement versus double-pool equilibrated Kt/V. CONCLUSIONS: Our data confirm the existence of a relationship between dialysis dose and survival that persisted despite correcting for known confounders. A model for predicting a high dose of dialysis is proposed with practical relevance.

Impact of the dialysate acid component on haemodialysis mortality rates.

BACKGROUND: No prospective study has evaluated the long-term effect on mortality of the new acid concentrates added to bicarbonate dialysate. The aim of this pharmacoepidemiological study was to evaluate the association between hydrochloric or citric acid-based dialysate and mortality on haemodialysis (HD). METHODS: This study included 117 796 patients with 3 723 887 months on HD recorded in the national French Renal Epidemiology and Information Network registry. Dialysate acid components were retrospectively reconstructed for each facility. All patients on HD were associated each month with an exposure based on that at their facility of treatment. We took each patient's time-varying exposure into account to calculate the monthly mortality rates for each exposure. Incidence rate ratios (IRRs) for mortality were calculated with a Poisson regression, with acetic acid as the reference. Regressions were adjusted for initial clinical characteristics (age, gender, previous cardiovascular events, active malignancy, diabetes, pulmonary disease, mobility), dialysis technique and location (in-centre, outpatient centre, self-care unit) and ESRD vintage, updated monthly. RESULTS: The crude mortality rate per 1000 patient-months with citric acid {11.5 [95% confidence interval (CI) 11.1-12.0]} was lower than with either acetic acid [12.9 (95% CI 12.8-13.1)] or hydrochloric acid [12.8 (95% CI 12.2-13.5)]. For the 2014-17 period, the IRR for mortality with citric acid [adjusted IRR 0.94 (95% CI 0.90-0.99)] and with hydrochloric acid [adjusted IRR 0.86 (95% CI 0.79-0.94)] were significantly lower than with acetic acid. CONCLUSION: This post-marketing study of long-term exposure to dialysate acidifiers at the patient level found the use of citric and hydrochloric acid-based dialysates, compared with acetic acid, was associated with lower mortality.

Effect of adding vildagliptin to insulin in haemodialysed patients with type 2 diabetes: The VILDDIAL study, a randomized, multicentre, prospective study.

AIM: To evaluate the effect of adding the dipeptidyl-peptidase-4 inhibitor vildagliptin to insulin on the glycaemic control of patients with type 2 diabetes undergoing haemodialysis. METHODS: Overall, 65 insulin-treated patients with type 2 diabetes undergoing haemodialysis (HbA1c: 7.3% ± 1.1%; age: 70.5 ± 8.5 years) were randomized (1:1) either to receive vildagliptin 50 mg/day in addition to insulin (vildagliptin-insulin group) or to pursue their usual insulin regimen (insulin-only group). Continuous glucose monitoring (CGM) was performed for 48 ± 6 hours at baseline and at week 12. The primary study endpoint was change from baseline in mean interstitial glucose using CGM. The secondary endpoints included other CGM variables and glucose control markers. RESULTS: After 12 weeks, a greater reduction in mean CGM glucose from baseline was observed in the vildagliptin-insulin group compared with the insulin-only group, although the between-treatment difference was not statistically significant (mean difference [CI 95%]: -0.96 mmol/L [-2.09; 0.18] vs. -0.29 mmol/L [-1.29; 0.76], P = 0.32). However, a significant decrease from baseline in HbA1c, glycated albumin and insulin daily doses was observed in the vildagliptin-insulin group versus the insulin-only group (-0.6% [-1.19; -0.1], P < 0.01), in the vildagliptin-insulin group versus no change in the insulin-only group (-130.6 µmol/L [-271; 10.7] vs. +36.2 µmol/L [-164.4; 236.9], P = 0.04 and - 5.9 IU/day [-1.8; 7.1] vs. +1.1 IU/day [-14.5; 16.6], P = 0.01, respectively). There was no significant difference in the percentage of time spent in hypoglycaemia using CGM, occurrence of severe hypoglycaemia or number of adverse events. CONCLUSION: In this study, vildagliptin added to insulin improved glycaemic control with an associated insulin-sparing effect in patients with type 2 diabetes undergoing haemodialysis and was well tolerated.

Metabolic syndrome in haemodialysis patients: prevalence, determinants and association to cardiovascular outcomes.

BACKGROUND: In the general population, metabolic syndrome (MetS) is predictive of major adverse cardiovascular events (MACE). Waist circumference (WC), a component of the MetS criteria, is linked to visceral obesity, which in turn is associated with MACE. However, in haemodialysis (HD) patients, the association between MetS, WC and MACE is unclear. METHODS: In a cross-sectional study of 1000 HD patients, we evaluated the prevalence and characterised the clinical predictors of MetS. The relationship between MetS and its components, alone or in combination, and MACE (coronary diseases, peripheral arteriopathy, stroke or cardiac failure), was studied using receiver operating characteristics (ROC) curves and logistic regression. RESULTS: A total of 753 patients were included between October 2011 and April 2013. The prevalence of MetS was 68.5%. Waist circumference (> 88 cm in women, 102 cm in men) was the best predictor of MetS (sensitivity 80.2; specificity 82.3; AUC 0.80; p <  0.05). In multivariate analysis, MetS was associated with MACE (OR: 1.85; 95CI 1.24-2.75; p <  0.01), but not WC alone. There was a stronger association between the combination of abdominal obesity, hypertriglyceridaemia and low high-density lipoprotein cholesterol with MACE after exclusion of impaired fasting glucose and hypertension. CONCLUSIONS: MetS is frequent and significantly associated with MACE in our haemodialysis cohort and probably in other European dialysis populations as well. In HD patients, a new simplified definition could be proposed in keeping with the concept of the "hypertriglyceridaemic waist".

Relative prognostic impact of nutrition, anaemia, bone metabolism and cardiovascular comorbidities in elderly haemodialysis patients.

BACKGROUND: The prognostic impact of nutrition and chronic kidney disease (CKD) complications has already been described in elderly haemodialysis patients but their relative weights on risk of death remain uncertain. Using structural equation models (SEMs), we aimed to model a single variable for nutrition, each CKD complication and cardiovascular comorbidities to compare their relative impact on elderly haemodialysis patients' survival. METHODS: This prospective study recruited 3165 incident haemodialysis patients ≥75 years of age from 178 French dialysis units. Using SEMs, the following variables were computed: nutritional status, anaemia, mineral and bone disorder and cardiovascular comorbidities. Systolic blood pressure was also used in the analysis. Survival analyses used Poisson models. RESULTS: The population average age was 81.9 years (median follow-up 1.51 years, 35.5% deaths). All variables were significantly associated with mortality by univariate analysis. Nutritional status was the variable most strongly associated with mortality in the multivariate analysis, with a negative prognostic impact of low nutritional markers {incidence rate ratio [IRR] 1.42 per 1 standard deviation [SD] decrement [95% confidence interval (CI) 1.32-1.53]}. The 'cardiovascular comorbidities' variable was the second variable associated with mortality [IRR 1.19 per 1 SD increment (95% CI 1.11-1.27)]. A trend towards low intact parathyroid hormone and high serum calcium and low values of systolic blood pressure were also associated with poor survival. The variable 'anaemia' was not associated with survival. CONCLUSIONS: These findings should help physicians prioritize care in elderly haemodialysis patients with CKD complications, with special focus on nutritional status.