Strategies to Reduce Rehospitalization in Patients with CKD and Kidney Failure

Obesity Metabolic Phenotypes and Unplanned Readmission Risk in Diabetic Kidney Disease: An Observational Study from the Nationwide Readmission Database

BACKGROUND AND AIM

Obesity is a potentially modifiable factor for reducing readmissions, with heterogeneity that varies according to the metabolic status. Our objective was to examine the independent or mutual relationship between obesity and metabolic abnormalities and diabetic kidney disease (DKD)-related hospitalizations.

METHODS

493,570 subjects with DKD were enrolled in the 2018 Nationwide Readmission Database (NRD, United States). The at-risk population was reclassified into refined obesity subtypes based on the body mass index (BMI) classification of metabolic abnormalities (hypertension and/or dyslipidemia) to investigate the 180 d readmission risk and hospitalization costs related to DKD.

RESULTS

The overall readmission rate was 34.1%. Patients with metabolic abnormalities, regardless of obesity, had a significantly higher risk of readmission compared to non-obese counterparts (adjusted HR, 1.11 [95% CI, 1.07-1.14]; 1.12 [95% CI, 1.08-1.15]). Hypertension appeared to be the only metabolic factor associated with readmission among individuals with DKD. Obesity without metabolic abnormalities was independently associated with readmission (adjusted HR,1.08 [1.01,1.14]), especially among males and those >65 years (adjusted HR,1.10 [1.01-1.21]; 1.20 [1.10-1.31]). Women or those ≤65 years with metabolic abnormalities (all p <0.050) had elevated readmission rates, regardless of obesity; however, no such trend was observed in obese subjects without metabolic abnormalities (adjusted HR, 1.06 [0.98,1.16]). Additionally, obesity and metabolic abnormalities were associated with elevated hospitalization costs (all p <0.0001).

CONCLUSIONS

Increased BMI and hypertension are positively associated with readmissions and related costs among patients with DKD, which should be considered in future studies.

Burden of Hypertensive Crisis in Patients With End-Stage Kidney Disease on Maintenance Dialysis: Insights From United States Renal Data System Database

BACKGROUND

There is paucity of information on the incidence, clinical characteristics, admission trends, and outcomes of hypertensive crisis (HTN-C) in patients with end-stage kidney disease (ESKD) who are on maintenance dialysis.

METHODS

We conducted a retrospective observational study of HTN-C admissions in patients with end-stage kidney disease using the United States Renal Data System. We identified patients with end-stage kidney disease aged ≥18 years on dialysis and were hospitalized for HTN-C from January 2006 to August 2015.

RESULTS

A total of 54 483 patients with end-stage kidney disease were hospitalized for HTN-C during the study period. After study exclusions, 37 214 patients were included in the analysis. A majority of patients were Black, there were more women than men and the South region of the country accounted for a great majority of patients. During the study period, hospitalization rates increased from 1060 per 100 000 beneficiary years to 1821 (P_trend<0.0001). Overall, in-hospital mortality, 30-day, and 1-year mortality were 0.6%, 2.3%, and 21.8%, respectively, and 30-day readmission rate was 31.1%. During the study period, most study outcomes showed a significant decreasing trend (in-hospital mortality 0.6%-0.5%, 30-day mortality 2.4%-1.9%, 1-year mortality 23.9%-19.7%, P_trend<0.0001 for all).

CONCLUSIONS

Hospitalizations for HTN-C have increased consistently during the decade studied. Although temporal trends showed improving mortality and readmission rates, the absolute rates were still high with 1 in 3 patients readmitted within 30 days and 1 in 5 patients dying within 1 year of index hospitalization.

Readmission rates and risk factors for readmission after transcatheter aortic valve replacement in patients with end-stage renal disease

Objectives

We sought to examine readmission rates and predictors of hospital readmission following TAVR in patients with ESRD.

Background

End-stage renal disease (ESRD) is associated with poor outcomes following transcatheter aortic valve replacement (TAVR).

Methods

We assessed index hospitalizations for TAVR from the National Readmissions Database from 2017 to 2018 and used propensity scores to match those with and without ESRD. We compared 90-day readmission for any cause or cardiovascular cause. Length of stay (LOS), mortality, and cost were assessed for index hospitalizations and 90-day readmissions. Multivariable logistic regression was performed to identify predictors of 90-day readmission.

Results

We identified 49,172 index hospitalizations for TAVR, including 1,219 patients with ESRD (2.5%). Patient with ESRD had higher rates of all-cause readmission (34.4% vs. 19.2%, HR 1.96, 95% CI 1.68–2.30, p<0.001) and cardiovascular readmission (13.2% vs. 7.7%, HR 1.85, 95% CI 1.44–2.38, p<0.001) at 90 days. During index hospitalization, patients with ESRD had longer length of stay (mean difference 1.9 days), increased hospital cost (mean difference $42,915), and increased in-hospital mortality (2.6% vs. 0.9%). Among those readmitted within 90 days, patients with ESRD had longer LOS and increased hospital charge, but similar in-hospital mortality. Diabetes (OR 1.86, 95% CI 1.31–2.64) and chronic pulmonary disease (OR 1.51, 95% CI 1.04–2.18) were independently associated with higher odds of 90-day readmission in patients with ESRD.

Conclusion

Patients with ESRD undergoing TAVR have higher mortality and increased cost associated with their index hospitalization and are at increased risk of readmission within 90 days following TAVR.

Chronic kidney disease, risk of readmission, and progression to end-stage renal disease in 519,387 patients undergoing coronary artery bypass grafting

Objective

The association between chronic kidney disease and adverse outcomes after coronary artery bypass grafting is well established; in contrast, the association between chronic kidney disease and readmission has been less thoroughly investigated. We hypothesized that patients at higher chronic kidney disease stages have greater risk of readmission, poorer operative outcomes, and greater hospitalization cost.

Methods

Using the 2016-2018 Nationwide Readmissions Database, we identified 519,387 patients who underwent isolated coronary artery bypass grafting. Patients were stratified by chronic kidney disease stage based on International Classification of Diseases 10^th Revision classification. Multivariable logistic regression was used to assess risk factors for in-hospital mortality and 90-day readmission.

Results

Hospital readmission, in-hospital mortality, and cost progressively increased with worsening chronic kidney disease stage; patients with end-stage renal disease had the highest in-hospital mortality rate (7.2%), hospitalization costs ($59,616) (P < .001), and 90-day readmission rate (40%) (P < .001). Chronic kidney disease stage greater than 3 was associated with in-hospital mortality (odds ratio, 1.56, 95% confidence interval, 1.40-1.73; P < .001) and 90-day readmission (odds ratio, 1.66, 95% confidence interval, 1.56-1.76; P < .001). At 30 days after discharge, new-onset dialysis dependence was more frequent in patients readmitted with chronic kidney disease 4 to 5 (8.9%; n = 1495) than in patients with chronic kidney disease 1 to 3 (1.4%; n = 8623) and patients without chronic kidney disease (0.3%; n = 38,885). At 90 days after discharge, dialysis dependence increased to 11.1% (n = 1916) in readmitted patients with chronic kidney disease 4 to 5 but remained stable for patients with chronic kidney disease 1 to 3 (1.4%; n = 10,907) and patients without chronic kidney disease (0.3%; n = 50,200).

Conclusions

Chronic kidney disease stage is strongly associated with mortality, new-onset dialysis dependence, readmission, and higher cost after coronary artery bypass grafting. Patients with chronic kidney disease 4 and 5 and patients with end-stage renal disease are readmitted at the highest rates. Although further research is needed, a targeted approach may reduce costly readmissions and improve outcomes after coronary artery bypass grafting in patients with chronic kidney disease.

A Web-based, Provider-driven Mobile App to Enhance Patient Care Coordination between Dialysis Facilities and Hospitals: Development and Pilot Implementation Study (Preprint)

Background

Objective

Methods

Results

Conclusions

Silencing of O-linked N-acetylglucosamine transferase ameliorates hypercalcemia-induced neurotoxicity in renal failure by regulating EZH2/KLF2/CXCL1 axis

Hypocalcemia, associated with Calcium neurotoxicity, has been reported to induce nerve dysfunction, which is a significant problem of renal failure. This study identifies a molecular mechanism of the O-linked N-acetylglucosamine transferase (OGT)-mediated enhancer of zeste homolog 2 (EZH2)/krüppel-like factor 2 (KLF2)/chemokine (C-X-C motif) ligand 1 (CXCL1) axis underlying the hypercalcemia-induced nerve injury in renal failure. Bioinformatics analyses were used to screen out the key factors in hypercalcemia-induced nerve injury in renal failure. Chronic kidney disease (CKD) was induced by an adenine diet in mice, followed by injection of adenovirus vector carrying short hairpin RNA targeting OGT, followed by behavioral tests and collection of the cerebral cortex for primary neurons. Calcium level in neurons was measured by Fluo-4-am and Perkin Elmer+ Operetta. Neuronal apoptosis and viability were detected by flow cytometry and the MTS method. The binding of EZH2 to KLF2 promoter was verified by chromatin immunoprecipitation assay. The concentration of Ca2+ in brain tissues of CKD model mice was increased, and nerve functions were obviously damaged. High expression of OGT occurred in kidney tissue of CKD model mice. Silencing OGT reduced the hypercalcemia-induced toxicity of neurons by inhibiting the expression of EZH2, which elevated the expression of CXCL1 in primary neurons by diminishing KLF2. Silencing OGT attenuated hypercalcemia-induced neurotoxicity by regulating the EZH2/KLF2/CXCL1 axis. In vivo experiments further confirmed that silencing OGT could reduce hypercalcemia-induced nerve injury in CKD mice. Taken together, silencing OGT downregulates EZH2, which increases the expression of KLF2 and then decreases the expression of CXCL1, thus alleviating hypercalcemia-induced nerve injury in renal failure.

Hospitalization Trajectories and Risks of ESKD and Death in Individuals With CKD

INTRODUCTION

Management of chronic kidney disease (CKD) entails high medical complexity and often results in high hospitalization burden. There are limited data on the associations of longitudinal hospital utilization patterns with adverse clinical outcomes in individuals with CKD.

METHODS

We derived cumulative all-cause hospitalization trajectory groups using latent class trajectory analysis in 3012 participants of the Chronic Renal Insufficiency Cohort (CRIC) Study who were alive and did not reach end-stage kidney disease (ESKD) within 4 years of study entry. Cox proportional hazards models tested the associations between hospitalization trajectory groups and risks of ESKD and death prior to the onset of ESKD (ESKD-censored death).

RESULTS

Within 4 years of study entry, there were 5658 hospitalizations among 3012 participants. We identified 3 distinct subgroups of individuals with CKD based on cumulative all-cause hospitalization trajectories over 4 years: low-utilizer (n = 1066), intermediate-utilizer (n = 1802), and high-utilizer (n = 144). High-utilizers represented a patient population of lower socioeconomic status who had a greater prevalence of comorbid conditions and lower kidney function compared with intermediate- and low-utilizers. After the 4-year ascertainment period to form the trajectory subgroups, there were 544 ESKD events and 437 ESKD-censored deaths during a median follow-up time of 5.1 years. Compared with low-utilizers, intermediate-utilizers and high-utilizers were at 1.49-fold (95% confidence interval [CI] 1.22-1.84) and 1.75-fold (95% CI 1.20-2.56) higher risk of ESKD in adjusted analyses, respectively. Compared with low-utilizers, intermediate-utilizers and high-utilizers were at 1.48-fold (95% CI 1.17-1.87) and 2.58-fold (95% CI 1.74-3.83) higher risk of ESKD-censored death in adjusted analyses, respectively.

CONCLUSIONS

Trajectories of cumulative all-cause hospitalization identify subgroups of individuals with CKD who are at high risk of ESKD and death.