Cardiovascular Outcomes of Transcatheter Aortic Valve Implantation in Patients With Chronic Kidney Disease in Octogenarian Population

Limited data are available regarding in-hospital outcomes of transcatheter aortic valve implantation (TAVI) in the octogenarian population with chronic kidney disease (CKD). We sought to study the cardiovascular outcomes of TAVI in CKD hospitalization with different stages at the national cohort registry. We used the National Inpatient Sample database to compare TAVI CKD low-grade (LG) (stage I to IIIa, b) versus TAVI CKD high-grade (HG) (stage IV to V) in octogenarians. Outcomes such as inpatient mortality, cardiogenic shock, new permanent pacemaker implantation, acute kidney injury), sudden cardiac arrest, mechanical circulatory support, major bleeding, transfusion, and resource utilization were compared between the 2 cohorts. A total of 74,766 octogenarian patients (TAVI CKD-HG n = 12,220; TAVI CKD-LG n = 62,545) were included in our study. On matched analysis, TAVI CKD-HG had higher odds of in-hospital mortality (adjusted odds ratio [aOR] 2.18, 95% confidence interval [CI] 1.0-2.5, p <0.0001), cardiogenic shock (aOR 1.22, 95% CI 1.07 to 1.39, p = 0.0019), permanent pacemaker implantation (aOR 1.14, 95% CI 1.06 to 1.23, p = 0.0006), acute kidney injury (aOR 1.19, 95% CI 1.13 to 1.27, p <0.0001), sudden cardiac arrest (aOR 1.32, 95% CI 1.09 to 1.61, p = 0.004), major bleeding (aOR 1.1, 95% CI 1.006 to 1.22, p <0.0368) and higher rates of blood transfusion (aOR 1.62, 95% CI 1.5 to 1.75, p <0.0001) when compared with the TAVI CKD-LG cohort. However, there was no statistically significant difference in the odds of cerebrovascular accident and mechanical circulatory support use between the 2 groups.

Questionable Validity of Creatinine-Based eGFR in Elderly Patients but Cystatin C Is Helpful in First-Line Diagnostics

BACKGROUND

The recommended chronic kidney disease (CKD) first-line diagnostic test is based on the creatinine-derived (estimated) glomerular filtration rate (eGFR). Cystatin C use may provide a better assessment.

METHODS

We compared creatinine- and cystatin C-derived eGFR determination as the first-line diagnostic test for 112 hospital patients aged > 60 years (median = 76 years). The patients were judged to not have CKD (no-CKD group) according to the first-line diagnostic recommendations (n = 61, eGFR (CKD Epidemiology Collaboration (CKD-EPI)) ≥ 60 mL/min/1.73 m2, total urine protein < 150 mg/g creatinine, urinary red/white blood cells not increased) or classified to be at risk for kidney insufficiency due to aortic valve dysfunction (at-risk group; n = 51). The accuracy of the eGFR values was evaluated retrospectively with the final case diagnoses.

RESULTS

The eGFR (Caucasian, Asian, pediatric, and adult formula (CAPA)) was found to be linearly correlated to the eGFR (CKD-EPI) (R2 = 0.5, slope = 0.69, p < 0.0001). In 93/112 (>80%) cases, the eGFR (CAPA) yielded lower values (on average ≈-20%). In 55/112 (49%) cases, the cystatin C-derived CKD stage was lower. CKD reclassification from no-CKD to a kidney-insufficient state (i.e., CKD1/2 to CKD3a/b or 4) or reclassification to a more severe kidney insufficiency (i.e., CKD3a → 3b/4 or 3b → 4) was found in 41/112 (37%) cases. A worse CKD classification (no-CKD → kidney-insufficient) based on the eGFR (CAPA) was plausible in 30% of cases in light of the final case diagnoses.

CONCLUSION

In elderly patients (>60 years), renal function appears to be systematically overestimated by the creatinine-based eGFR (CKD-EPI), indicating that, for this group, the cystatin C-based eGFR (CAPA) should be used as the first-line diagnostic test.

Nrf2 Protein Serum Concentration in Human CKD Shows a Biphasic Behavior

Oxidative stress contributes to the progression of chronic kidney disease (CKD) and CKD-related mortality. The nuclear factor erythroid 2-related factor 2 (Nrf2) is essential in the regulation of cellular redox status, and Nrf2-activating therapies are under evaluation in several chronic diseases, including CKD. It is therefore inevitable to understand how Nrf2 behaves in advancing CKD. We analyzed Nrf2 protein concentrations in patients with varying extents of CKD but without renal replacement therapy, and in healthy subjects. Compared to healthy controls, Nrf2 protein was upregulated in mild to moderate kidney function impairment (G1-3). Within the CKD population, we found a significant positive correlation between Nrf2 protein concentration and kidney function (estimated glomerular filtration rate). In severe kidney function impairment (G4,5), Nrf2 protein was reduced compared to mild to moderate kidney function impairment. We conclude that Nrf2 protein concentration in severe kidney function impairment is reduced relative to the mild to moderate kidney function impairment where increased Nrf2 protein concentrations prevail. With respect to the implementation of Nrf2 targeted therapies, it will be necessary to explore in which population of patients with CKD such therapies are able to effectively add to the endogenous Nrf2 activity.

The association between vitamin D deficiency and risk of renal event: Results from the Korean cohort study for outcomes in patients with chronic kidney disease (KNOW-CKD)

Backgrounds

Some observational studies have suggested a possible association between vitamin D deficiency and CKD. However, in most studies, the causality between low levels of vitamin D and risk of renal events could not be explained. We investigated the relationship between vitamin D deficiency and risk of severe CKD stage and renal event in a large-scale prospective cohort study.

Methods

We used data from a prospective cohort of 2,144 patients with available information on serum 25-hydroxyvitamin D (25(OH)D) levels at baseline from KNOW-CKD, 2011-2015 were included. Vitamin D deficiency was defined as serum 25(OH)D levels < 15 ng/mL. We performed a cross-sectional analysis to elucidate the relationship between 25(OH)D and CKD stage using baseline CKD patient data. We further examined a cohort analysis to clarify the association between 25(OH)D and risk of renal event. Renal event was a composite of the first occurrence of a 50% decline in eGFR from the baseline value or the onset of CKD stage 5 (initiation of dialysis or kidney transplantation) across the follow-up period. We also investigated the associations of vitamin D deficiency with risk of renal event according to diabetes and overweight status.

Results

Vitamin D deficiency were significantly associated with an increased risk of severe CKD stage - 1.30-fold (95% CI: 1.10-1.69) for 25(OH)D. Deficiency of 25(OH)D with 1.64-fold (95% CI: 1.32-2.65) was related to renal event compared with the reference. Furthermore, vitamin D deficiency patients with presence of DM and overweight status also displayed higher risk than non-deficient patients for risk of renal event.

Conclusion

Vitamin D deficiency is associated with significantly increased risk of severe CKD stage and renal event.

Factors associated with the absence of pharmacological treatment for common modifiable complications in children with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is associated with many comorbidities requiring complex management. We described treatment patterns for common modifiable CKD complications (high blood pressure, anemia, hyperphosphatemia, and acidosis) according to severity of CKD and examined factors associated with the absence of drug therapy, among participants with a persistent comorbidity, for 1 year in children enrolled in the CKiD study.

METHODS

A total of 703 CKiD participants contributed 2849 person-visits over a median 3.5 years of follow-up. Using pairs of annual visits, we examined whether participants with abnormal biomarker levels at the first (index) visit persisted in the abnormal levels 1 year later according to CKD risk stage. Multivariate analyses identified demographic and clinical factors associated with the absence of drug therapy among those with persistent comorbid conditions for 1 year.

RESULTS

The overall proportions of person-visits prescribing therapy at 1-year follow-up for treating anemia, acidosis, hyperphosphatemia, and high blood pressure were 54%, 45%, 29%, and 81%, respectively. The frequency of therapy increased with advanced CKD risk stage for all comorbidities; however, 19-23% of participants with acidosis, 24-27% with anemia, and 30-39% with hyperphosphatemia at high-risk stages (E and F) were not prescribed appropriate therapy despite the persistence of abnormal levels of these biomarkers for at least 1 year. The resolution of comorbidities at advanced CKD stages without treatment was unlikely.

CONCLUSIONS

Many children with CKD in the CKiD cohort did not receive pharmacological treatment for common and persistent modifiable comorbidities, even in severe CKD risk stages.

Glucose-Lowering Medication Use in CKD: Analysis of US Medicare Beneficiaries Between 2007 and 2016

BACKGROUND

Information regarding the use of glucose-lowering medications in patients with chronic kidney disease (CKD) is limited.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Medicare 5% random sample of patients with CKD with type 2 diabetes, 2007 to 2016.

PREDICTORS

Study year, CKD stage, low-income subsidy status, and demographic characteristics (age, sex, and race/ethnicity).

OUTCOMES

Trends in use of glucose-lowering medications.

ANALYTICAL APPROACH

Yearly cohorts of patients with CKD and type 2 diabetes were created. Descriptive statistics were used to report proportions of patients using glucose-lowering medications. To test overall trends in glucose-lowering medication classes, linear probability models with adjustment for age, sex, race/ethnicity, CKD stage, and low-income subsidy status were used.

RESULTS

Metformin use increased significantly from 32.7% in 2007 to 48.7% in 2016. Use of newer classes of glucose-lowering medications increased significantly, including dipeptidyl peptidase 4 inhibitors (5.6%, 2007; 21.7%, 2016), glucagon-like peptide 1 receptor agonists (2.3%, 2007; 6.1%, 2016), and sodium-glucose cotransporter 2 inhibitors (0.2%, 2013; 3.3%, 2016). Newer insulin analogue use increased from 37.2% in 2007 to 46.3% in 2013 and then remained steady. Use of sulfonylureas, thiazolidinediones, older insulins (human regular and neutral protamine Hagedorn), α-glucosidase inhibitors, amylin mimetics, and meglitinides decreased significantly. Insulin was the most highly used single medication class. Insulin use was higher among low-income subsidy than among non-low-income subsidy patients. Combination therapy was less common as CKD stage increased.

LIMITATIONS

Patients with CKD and type 2 diabetes and the CKD stages were identified with diagnosis codes and could not be verified through medical record review. Our results may not be generalizable to younger patients with CKD with type 2 diabetes.

CONCLUSIONS

Use of metformin and newer glucose-lowering medication classes is increasing in patients with CKD with type 2 diabetes. We anticipate that percentages of patients with CKD using these newer agents will increase.

Neutrophil-to-lymphocyte ratio predicts long-term all-cause mortality in patients with chronic kidney disease stage 5

INTRODUCTION

A high neutrophil-to-lymphocyte ratio (NLR) has been reported to be a strong biomarker of inflammation.

AIM

We sought to evaluate the impact of NLR on long-term all-cause and cardio-vascular (CV) mortality in hemodialysis (HD) patients.

MATERIAL AND METHODS

total of 84 chronic kidney disease (CKD) stage 5 patients with 54 of them on HD, with a median age of 61.5 (51.3-74.8) years were enrolled. e association between NLR and clinical biomarkers was investigated. Multivariable Cox regression analysis was used to find significant predictors of all-cause and CV mortality at follow-up.

RESULTS

the median NLR (interquartile range) was 3.0 (2.1-4.1). Patients with NLR ≥3.9 (the highest tertile) had higher five-year all-cause mortality then remaining patients (53.6% vs. 30.4%; p = 0.039). On the contrary, only a trend towards increased CV mortality was observed (25.0% vs. 42.9%; p = 0.10). NLR ≥3.9 was a significant predictor of all-cause mortality at five years [hazard ratio (95%CI): 2.23 (1.10-4.50); p = 0.025] in Cox regression model adjusted for age, gender, and diabetes status. Similarly, while using NLR as continuous variable a significant association between NLR and all-cause mortality was confirmed even a er adjustment for covariates [hazard ratio per 1 unit increase (95%CI): 1.26 (1.06-1.51); p = 0.009] with the area under the receiver operating characteristic (ROC) curve of 0.64. Correlations between NLR and WBC, concentration of fibrinogen, albumin were observed.

CONCLUSIONS

Asymptomatic inflammation measured by NLR showed an association with long-term all-cause mortality in stage 5 CKD patients, even while white blood cell count was in the normal range.

[The accuracy of hospital discharge records and their use in identifying and staging chronic kidney disease]

Administrative databases contain precious information that can support the identification of specific pathologies. Specifically, chronic kidney disease (CKD) patients could be identified using hospital discharge records (HDR); these should contain information on the CKD stage using subcategories of the ICD9-CM classification's 585 code (subcategories can be expressed just by adding a fourth digit to this code). To verify the accuracy of HDR data regarding the coding of CKD collected in the Italian region Emilia-Romagna, we analyzed the HDR records of patients enrolled in the PIRP project, which could easily be matched with eGFR data obtained through laboratory examinations. The PIRP database was used as the gold standard because it contains data on CKD patients followed up since 2004 in thirteen regional nephrology units and includes data obtained from reliable and homogeneous laboratory measurement. All HDR of PIRP patients enrolled between 2009 and 2017 were retrieved and matched with available laboratory data on eGFR, collected within 15 days before or after discharge. We analyzed 4.168 HDR, which were classified as: a) unreported CKD (n=1.848, 44.3%); b) unspecified CKD, when code 585.9 (CKD, not specified) or 586 was used (n=446, 10.7%); c) wrong CKD (n=833, 20.0%); d) correct CKD (n=1041, 25.0%). We noticed the proportion of unreported CKD growing from 32.9% in 2009 to 56.6% in 2017, and the correspondent proportion of correct CKDs decreasing from 25.4% to 22.3%. Across disciplines, Nephrology showed the highest concordance (69.1%) between the CKD stage specified in the HDRs and the stage reported in the matched laboratory exam, while none of the other disciplines, except for Geriatrics, reached 20% concordance. When the CKD stage was incorrectly coded, it was generally underestimated; among HDRs with unreported or unspecified CKD at least half of the discharges were matched with lab exams reporting CKD in stage 4 or 5. We found that the quality of CKD stage coding in the HDR record database was very poor, and insufficient to identify CKD patients unknown to nephrologists. Moreover, the growing proportion of unreported CKD could have an adverse effect on patients' timely referral to a nephrologist, since general practitioners might remain unaware of their patients' illness. Actions aimed at improving the training of the operators in charge of HDRs compilation and, most of all, at allowing the exploitation of the informative potential of HDRs for epidemiological research are thus needed.

Relationship of Estimated GFR and Albuminuria to Concurrent Laboratory Abnormalities: An Individual Participant Data Meta-analysis in a Global Consortium

RATIONALE & OBJECTIVE

Chronic kidney disease (CKD) is complicated by abnormalities that reflect disruption in filtration, tubular, and endocrine functions of the kidney. Our aim was to explore the relationship of specific laboratory result abnormalities and hypertension with the estimated glomerular filtration rate (eGFR) and albuminuria CKD staging framework.

STUDY DESIGN

Cross-sectional individual participant-level analyses in a global consortium.

SETTING & STUDY POPULATIONS

17 CKD and 38 general population and high-risk cohorts.

SELECTION CRITERIA FOR STUDIES

Cohorts in the CKD Prognosis Consortium with data for eGFR and albuminuria, as well as a measurement of hemoglobin, bicarbonate, phosphorus, parathyroid hormone, potassium, or calcium, or hypertension.

DATA EXTRACTION

Data were obtained and analyzed between July 2015 and January 2018.

ANALYTICAL APPROACH

We modeled the association of eGFR and albuminuria with hemoglobin, bicarbonate, phosphorus, parathyroid hormone, potassium, and calcium values using linear regression and with hypertension and categorical definitions of each abnormality using logistic regression. Results were pooled using random-effects meta-analyses.

RESULTS

The CKD cohorts (n=254,666 participants) were 27% women and 10% black, with a mean age of 69 (SD, 12) years. The general population/high-risk cohorts (n=1,758,334) were 50% women and 2% black, with a mean age of 50 (16) years. There was a strong graded association between lower eGFR and all laboratory result abnormalities (ORs ranging from 3.27 [95% CI, 2.68-3.97] to 8.91 [95% CI, 7.22-10.99] comparing eGFRs of 15 to 29 with eGFRs of 45 to 59mL/min/1.73m2), whereas albuminuria had equivocal or weak associations with abnormalities (ORs ranging from 0.77 [95% CI, 0.60-0.99] to 1.92 [95% CI, 1.65-2.24] comparing urinary albumin-creatinine ratio > 300 vs < 30mg/g).

LIMITATIONS

Variations in study era, health care delivery system, typical diet, and laboratory assays.

CONCLUSIONS

Lower eGFR was strongly associated with higher odds of multiple laboratory result abnormalities. Knowledge of risk associations might help guide management in the heterogeneous group of patients with CKD.

Pregnancy and Kidney Outcomes in Patients With IgA Nephropathy: A Cohort Study

BACKGROUND

The outcomes of pregnancy in immunoglobulin A nephropathy (IgAN) are controversial. This cohort study assessed the effects of pregnancy on kidney disease progression and risk factors for adverse pregnancy outcomes in patients with IgAN.

STUDY DESIGN

A cohort study.

SETTING & PARTICIPANTS

Women of child-bearing age with IgAN and minimum follow-up of 1 year after biopsy from December 2003 to September 2014.

PREDICTORS

Pregnancy, treated as a time-dependent variable; baseline (at time of biopsy) estimated glomerular filtration rate (eGFR), proteinuria, blood pressure, and kidney pathology (Oxford MEST classification).

OUTCOMES

Kidney disease progression event, defined as 30% decline in eGFR or end-stage kidney disease; rate of eGFR decline; and adverse pregnancy outcomes, including severe preeclampsia and fetal loss.

RESULTS

Of 413 patients enrolled, 266 (64.4%), 101 (24.5%), 40 (9.6%), and 6 (1.5%) had chronic kidney disease (CKD) stages 1, 2, 3, and 4, respectively. During follow-up, 104 had 116 pregnancies, of which 110 continued beyond week 20; 309 patients did not become pregnant. After adjustment for age, eGFR, mean arterial pressure, proteinuria, and pathology class at the time of biopsy, subsequent pregnancy among patients with CKD stages 3 to 4, but not CKD stages 1 to 2, was associated with faster eGFR decline (-7.44 vs -3.90mL/min/1.73m² per year; P=0.007) and increased incidence of kidney progression events (HR, 5.14; 95% CI, 1.16-22.74) compared with patients who did not become pregnant.

LIMITATIONS

Relatively small sample size and single-center experience.

CONCLUSIONS

Pregnancy accelerated kidney disease progression in women with IgAN and CKD stage 3, but not in those at stage 1 or 2.

Excess mortality attributable to chronic kidney disease. Results from the PIRP project

Although chronic kidney disease (CKD) has a high mortality rate, the estimation of CKD mortality burden in the general population may be challenging because CKD is not always listed as a cause of death in mortality registries. To overcome this limitation, relative survival was used to estimate the excess mortality attributable to CKD as compared to the general population using data of patients registered in the Prevenzione Insufficienza Renale Progressiva (PIRP) registry since 2005 and were followed up until 2013. Relative survival was the ratio of survival observed in CKD patients to the expected survival of the general population. Multivariate parametric survival analysis was used to identify factors predicting excess mortality. The relative survival of CKD patients at 9 years was 0.708. Survival was significantly lower in CKD patients with cardiovascular comorbidities, proteinuria, diabetes, anemia and high phosphate levels and in advanced CKD stages, males, older patients and those who underwent dialysis. Relative survival is a viable method to determine mortality attributable to CKD. Study limitations are that patients are representative only of CKD patients followed by nephrologists and that our follow-up duration may be relatively short as a model for mortality.