Acute kidney injury following coronary revascularization procedures in patients with advanced CKD

Cannabis Use and Risk of Acute Kidney Injury in Patients with Advanced Chronic Kidney Disease Transitioning to Dialysis

Background: The current social and legal landscape is likely to foster the medicinal and recreational use of cannabis. Synthetic cannabinoid use is associated with acute kidney injury (AKI) in case reports; however, the association between natural cannabis use and AKI risk in patients with advanced chronic kidney disease (CKD) is unknown. Materials and Methods: From a nationally representative cohort of 102,477 U.S. veterans transitioning to dialysis between 2007 and 2015, we identified 2215 patients with advanced CKD who had undergone urine toxicology (UTOX) tests within a year before dialysis initiation and had inpatient serial serum creatinine levels measured within 7 days after their UTOX test. The exposure of interest was cannabis use compared with no use as ascertained by the UTOX test. We examined the association of this exposure with AKI using logistic regression and inverse probability of treatment weighting with extensive adjustment for potential confounders. Results: The mean age of the overall cohort was 61 years; 97% were males, 51% were African Americans, 97% had hypertension, 76% had hyperlipidemia, and 75% were diabetic. AKI occurred in 56% of the cohort, and in multivariable-adjusted analysis, cannabis use (when compared with no substance use) was not associated with significantly higher odds of AKI (odds ratio 0.85, 95% confidence interval 0.38-1.87; p=0.7). These results were robust to various sensitivity analyses. Conclusions: In this observational study examining patients with advanced CKD, cannabis use was not associated with AKI risk. Additional studies are needed to characterize the impact of cannabis use on risk of kidney disease and injury.

Comparison of long-term cardiovascular and renal outcomes between percutaneous coronary intervention and coronary artery bypass grafting in multi-vessel disease with chronic kidney disease

Objective

This study aims to analyze cardiac and renal outcomes of chronic kidney disease (CKD) patients with multi-vessel disease who have undergone coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI).

Materials and methods

Chronic kidney disease patients with multi-vessel disease who underwent CABG or PCI were retrospectively selected from our database and divided into the PCI group [further stratified into PCI with complete revascularization (PCI-CR) and PCI with incomplete revascularization (PCI-IR) groups] and the CABG group. The primary endpoint was the composite of all-cause death, myocardial infarction (MI), or stroke at 5 years. The key secondary endpoint was the 5-year rate of the renal composite outcome, defined as >40% glomerular filtration rate decrease, initiation of dialysis, and/or kidney transplant. Outcomes were compared using Cox proportional hazards regression analysis, and the results were further adjusted by multivariable analyses and inverse probability weighting.

Results

Among the study population (n = 798), 443 (55.5%) patients received CABG and 355 (44.5%) patients received PCI. Compared with the CABG group, the PCI group had similar risk of the primary endpoint (CABG vs. PCI, 19.3% vs. 24.0%, HR: 1.28, 95% CI: 0.95–1.73, p = 0.11) and a lower risk of the renal composite outcome (36.6% vs. 31.2%, HR: 0.74, 95% CI 0.58–0.94, p = 0.03). In addition, PCI-IR was associated with a significantly higher risk of the primary endpoint than CABG (HR: 1.54, 95% CI: 1.11–2.13, p = 0.009) or PCI-CR (HR: 1.78, 95% CI: 1.09–2.89, p = 0.02). However, PCI-CR had a comparable 5-year death, MI, or stroke rate to CABG (HR: 0.86, 95% CI 0.54–1.38, p = 0.54).

Conclusion

Coronary artery bypass grafting showed an incidence of death, MI, or stroke similar to PCI but was associated with a higher risk of renal injury. PCI-CR had a prognosis comparable with that of CABG, while PCI-IR had worse prognosis. If PCI is chosen for revascularization in patients with CKD, achieving CR should be attempted to ensure favorable outcomes.

Clinical trial registration

[clinicaltrials.gov], identifier [NCT 03870815].

Association of dyskalemias with short-term health care utilization in patients with advanced CKD

BACKGROUND: Patients with advanced chronic kidney disease (CKD) are at high risk for dyskalemias, which may induce arrhythmias that require immediate emergent or hospital care. The association of dyskalemias with short-term hospital/emergency room (ER) visits in advanced CKD is understudied. OBJECTIVE: To assess the association of dyskalemias with short-term hospital/ER visits in an advanced CKD population. METHODS: From among 102,477 US veterans transitioning to dialysis from 2007 to 2015, we identified 21,366 patients with 2 predialysis outpatient eGFR < 30 ml/min/1.73m2 90-365 days apart (with the second eGFR serving as the index date) and at least 1 potassium (K) in the baseline period (1 year before index) and 1 outpatient K (oK) in the follow-up (1 year after the index but before dialysis initiation). We examined the association of time-varying hypokalemia (K < 3.5 mEq/L) and hyperkalemia (K > 5.5 mEq/L) vs referent (3.5-5.5 mEq/L) with separate hospital and ER visits within 2 calendar days following each oK value over the 1-year follow-up period from the index. We used generalized estimating equations with binary distribution and logit link to model the exposure-outcome relationship adjusted for various confounders. We conducted various subgroup and sensitivity analyses to test the robustness of our results. RESULTS: Over the 1-year follow-up, 125,266 oK measurements were observed, of which 6.8% and 3.7% were classified as hyper- and hypokalemia, respectively. In the multivariable-adjusted model, hyperkalemia (adjusted odds ratio [aOR] = 2.04; 95% CI = 1.88-2.21) and hypokalemia (aOR = 1.66; 95% CI = 1.48-1.86) were associated with significantly higher odds of hospital visits. Similarly, hyperkalemia (aOR = 1.83; 95% CI = 1.65-2.03) and hypokalemia (aOR = 1.24; 95% CI = 1.07-1.44) were associated with significantly higher odds of ER visits. Results were robust to subgroups and sensitivity analyses. CONCLUSIONS: In patients with advanced CKD, dyskalemias are associated with higher risk of hospital/ER visits. Interventions targeted at lowering the risk of dyskalemias might help in reducing the health care utilization and associated economic burden among patients with advanced CKD experiencing dyskalemias. DISCLOSURES: This study was supported by grant 5U01DK102163 from the National Institute of Health (NIH) to Kamyar Kalantar-Zadeh and Csaba P. Kovesdy and by resources from the US Department of Veterans Affairs. The data reported here have been supplied in part by the United States Renal Data System (USRDS). Support for VA/CMS data were provided by the Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Health Services Research and Development, VA Information Resource Center (project numbers SDR 02-237 and 98-004). Opinions expressed in this article are those of the authors and do not necessarily represent the opinion of the Department of Veterans Affairs or the funding institution. Kovesdy has received honoraria from Akebia, Ardelyx, Astra Zeneca, Bayer, Boehringer-Ingelheim, Cara Therapeutics, Reata, and Tricida unrelated to this study. Kalantar-Zadeh has received honoraria and/or support from Abbott, Abbvie, ACI Clinical (Cara Therapeutics), Akebia, Alexion, Amgen, American Society of Nephrology, Astra-Zeneca, Aveo, BBraun, Chugai, Cytokinetics, Daiichi, DaVita, Fresenius, Genentech, Haymarket Media, Hofstra Medical School, International Federation of Kidney Foundations, International Society of Hemodialysis, International Society of Renal Nutrition & Metabolism, Japanese Society of Dialysis Therapy, Hospira, Kabi, Keryx, Kissei, Novartis, OPKO, National Institutes of Health, National Kidney Foundations, Pfizer, Regulus, Relypsa, Resverlogix, Dr Schaer, Sandoz, Sanofi, Shire, Veterans Affairs, Vifor, UpToDate, and ZS-Pharma, unrelated to this study. Gatwood has received research support from AstraZeneca, Merck & Co., and GlaxoSmithKline unrelated to this study. Obi has received research support from Relypsa/Vifor Pharma Inc. The remaining authors declare that they have no relevant financial interests.

Chronic kidney disease

Chronic kidney disease is a progressive disease with no cure and high morbidity and mortality that occurs commonly in the general adult population, especially in people with diabetes and hypertension. Preservation of kidney function can improve outcomes and can be achieved through non-pharmacological strategies (eg, dietary and lifestyle adjustments) and chronic kidney disease-targeted and kidney disease-specific pharmacological interventions. A plant-dominant, low-protein, and low-salt diet might help to mitigate glomerular hyperfiltration and preserve renal function for longer, possibly while also leading to favourable alterations in acid-base homoeostasis and in the gut microbiome. Pharmacotherapies that alter intrarenal haemodynamics (eg, renin-angiotensin-aldosterone pathway modulators and SGLT2 [SLC5A2] inhibitors) can preserve kidney function by reducing intraglomerular pressure independently of blood pressure and glucose control, whereas other novel agents (eg, non-steroidal mineralocorticoid receptor antagonists) might protect the kidney through anti-inflammatory or antifibrotic mechanisms. Some glomerular and cystic kidney diseases might benefit from disease-specific therapies. Managing chronic kidney disease-associated cardiovascular risk, minimising the risk of infection, and preventing acute kidney injury are crucial interventions for these patients, given the high burden of complications, associated morbidity and mortality, and the role of non-conventional risk factors in chronic kidney disease. When renal replacement therapy becomes inevitable, an incremental transition to dialysis can be considered and has been proposed to possibly preserve residual kidney function longer. There are similarities and distinctions between kidney-preserving care and supportive care. Additional studies of dietary and pharmacological interventions and development of innovative strategies are necessary to ensure optimal kidney-preserving care and to achieve greater longevity and better health-related quality of life for these patients.

Atherosclerotic Vascular Disease Associated with Chronic Kidney Disease

Cardiovascular risk increases as glomerular filtration rate (GFR) declines in progressive renal disease and is maximal in patients with end-stage renal disease requiring maintenance dialysis. Atherosclerotic vascular disease, for which hyperlipidemia is the main risk factor and lipid-lowering therapy is the key intervention, is common. However, the pattern of dyslipidemia changes with low GFR and the association with vascular events becomes less clear. While the pathophysiology and management of patients with early chronic kidney disease (CKD) is similar to the general population, advanced and end-stage CKD is characterized by a disproportionate increase in fatal events, ineffectiveness of statin therapy, and greatly increased risk associated with coronary interventions. The most effective strategies to reduce atherosclerotic cardiovascular disease in CKD are to slow the decline in renal function or to restore renal function by transplantation.

Safety and Efficacy of Minimum- or Zero-Contrast IVUS-Guided Percutaneous Coronary Interventions in Chronic Kidney Disease Patients: A Systematic Review

Conventional percutaneous coronary interventions (PCIs) frequently cause severe complications in chronic kidney disease (CKD) patients. Low-to-zero contrast intravascular ultrasound (IVUS) guided PCIs are promising alternatives in the CKD setting. We aim to systematically review up-to-date literature that have reported data and outcomes of low-to-zero contrast PCIs performed in CKD patients. We searched Embase, PubMed, and Cochrane databases for full-text articles that reported original data regarding efficacy and/or safety outcomes of IVUS-guided PCIs in patients with CKD. The quality of non-randomized trials included was assessed using the Newcastle-Ottawa scale. Six papers were included in the present systematic review: One non-randomized trial, two case series, and three case reports. Given the literature reported so far, contrast-free and IVUS-guided PCI procedures in patients with CKD appear to be safe (both in cardiac and renal outcomes) with a comparable efficacy to the conventional procedure, even in complex atherosclerotic lesions. No patient included in the mentioned studies showed renal function deterioration and did not need renal replacement therapy after the zero-contrast IVUS-guided percutaneous procedures. From a cardiovascular point of view, this technique proved to be safe in terms of cardiovascular outcomes. The undesirable consequences of conventional PCI in the CKD population might soon be effectively hampered by safer low-to-zero contrast IVUS-guided PCI procedures after a mandatory and rigorous evidence-based validation in long-awaited randomized controlled trials.

Potassium Trajectories prior to Dialysis and Mortality following Dialysis Initiation in Patients with Advanced CKD

INTRODUCTION

Patients with advanced non-dialysis-dependent CKD (NDD-CKD) have a reduced ability for maintaining plasma potassium (K) in normal range. Deviation from normal plasma K ranges is associated with increased mortality; however, the average trajectory of plasma K over time in patients with advanced NDD-CKD and the outcomes associated with plasma K trajectory are unknown.

METHODS

We identified 34,167 US veterans with advanced NDD-CKD transitioning to dialysis between October 2007 and March 2015 with at least 1 K measurement each year over a 3-year period prior to dialysis transition (3-year prelude). The K trajectory defined as the change in K (slope) per year over the entire 3-year prelude was estimated using linear mixed-effects models. The association between unadjusted (crude) K slope (categorized as stable [-0.09 to 0.09 mEq/L/year], decreasing [≤-0.10 mEq/L/year], and increasing [≥0.10 mEq/L/year]) and time to all-cause and cardiovascular mortality during the 6 months following dialysis initiation was assessed using multivariable-adjusted survival models.

RESULTS

The crude and multivariable-adjusted K slopes (mean, 95% CI) over the 3-year prelude were 0.008 (0.0059, 0.0110) and -0.15 mEq/L/year (-0.19, -0.11), respectively. Decreasing K slope was associated with higher multivariable-adjusted risk of all-cause mortality (adjusted hazard ratio [95% CI] vs. stable K slope: 1.08 [1.00-1.17]). No association was observed between K slope and cardiovascular mortality.

DISCUSSION/CONCLUSION

The average intraindividual plasma K trajectory is remarkably stable in patients with advanced NDD-CKD. A decreasing K slope is associated with higher all-cause mortality risk.

Predialysis Potassium Variability and Postdialysis Mortality in Patients With Advanced CKD

Introduction

Patients with advanced non–dialysis-dependent chronic kidney disease (NDD-CKD) are prone to potassium (K) imbalances due to reduced kidney function. Both hypo- and hyperkalemia are associated with increased mortality; however, it is unclear if K variability before dialysis initiation is associated with outcomes after dialysis initiation.

Methods

We identified 34,167 US veterans with advanced NDD-CKD transitioning to dialysis between October 1, 2007, through March 31, 2015, who had at least 1 K measurement each year over a 3-year period before transition (3-year prelude). For each patient, a linear mixed-effects model was used to regress K over time (in years) over the 3-year prelude to derive K variability (square root of the average squared distance between the observed and estimated K). The main outcomes of interest were 6-month all-cause and cardiovascular mortality after dialysis initiation. Multivariable Cox and Fine-Gray competing risk regression adjusted for 3-year prelude K intercept, K slope (per year), demographics, smoking status, comorbidities, length of hospitalizations, body mass index, vascular access type, medications, average estimated glomerular filtration rate, and number of K measurements over the 3-year prelude were used to assess the association of K variability (expressed as quartiles) with all-cause and cardiovascular mortality, respectively.

Results

Higher prelude K variability was associated with higher multivariable-adjusted risk of all-cause mortality but not cardiovascular mortality (adjusted hazard/subhazard ratios [95% confidence interval] for highest quartile [vs. lowest] of K variability, 1.14 [1.03–1.25] and 0.99 [0.85–1.16] for all-cause and cardiovascular mortality, respectively).

Conclusion

Higher K variability is associated with higher all-cause mortality after dialysis initiation.

Longer Predialysis ACEi/ARB Utilization Is Associated With Reduced Postdialysis Mortality

BACKGROUND

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ACEi/ARB) improve predialysis outcomes; however, ACEi/ARB are underused in patients transitioning to dialysis. We examined the association of different patterns of predialysis ACEi/ARB use with postdialysis survival and whether potentially modifiable adverse events are associated with lower predialysis ACEi/ARB use.

METHODS

This was a historic cohort study of 34,676 US veterans with, and 10,690 without, ACEi/ARB exposure in the 3-year predialysis period who subsequently transitioned to dialysis between 2007 and 2014. Associations of different patterns of predialysis ACEi/ARB use with postdialysis all-cause mortality and with predialysis acute kidney injury and hyperkalemia events were examined using multivariable adjusted regression analyses.

RESULTS

The mean age of the cohort was 70 years, 98% were males and 27% were African Americans. Compared to ACEi/ARB nonuse, continuous ACEi/ARB use was associated with lower postdialysis all-cause mortality (adjusted hazard ratio [aHR]; 95% confidence interval [95% CI] 0.87; 0.83-0.92). In analyses modeling the duration of predialysis ACEi/ARB use, ACEi/ARB use of 50%-74% and ≥75% were associated with lower mortality compared to nonuse (adjusted hazard ratio, 95% confidence interval 0.96, 0.92-0.99 and 0.91; 0.88-0.94, respectively), whereas no increase in postdialysis survival was observed with shorter predialysis ACEi/ARB use. Predialysis acute kidney injury was associated with shorter duration (<50%) of ACEi/ARB use and hyperkalemia was associated with interrupted and ACEi/ARB use of <75%.

CONCLUSIONS

Longer predialysis ACEi/ARB exposure was associated with lower postdialysis mortality. Prospective studies are needed to evaluate the benefits of strategies enabling uninterrupted predialysis ACEi/ARB use.

Revascularization Strategies in Patients with Chronic Kidney Disease and Acute Coronary Syndromes

PURPOSE OF REVIEW

Chronic kidney disease (CKD) is a highly prevalent condition that increases the incidence and complexity of acute coronary syndrome (ACS). The purpose of this review is to summarize current evidence, uncertainties, and opportunities in the management of patients with CKD and ACS, with a focus on revascularization.

RECENT FINDINGS

Patients with CKD have been systematically under-represented or excluded from clinical trials in ACS. Available data, however, demonstrates that although patients with CKD and ACS benefit from revascularization, they are also less likely to receive recommended medical and revascularization therapies when compared to patients with normal kidney function. Despite the increased short-term risk of major morbidity and mortality, patients with CKD and ACS should be considered for an early invasive strategy while also trying to mitigate the risks of procedural related complications. Until evidence emerges from randomized clinical trials, the decision about revascularization strategy should involve multi-disciplinary collaboration, heart team consensus, and patient shared decision-making.