Evolution of Echocardiographic Measures of Cardiac Disease From CKD to ESRD and Risk of All-Cause Mortality: Findings From the CRIC Study

Factors associated with risk analysis for asymptomatic left ventricular diastolic dysfunction in nondialysis patients with chronic kidney disease

Heart failure (HF) constitutes a major determinant of outcome in chronic kidney disease (CKD) patients. The main pattern of HF in CKD patients is preserved ejection fraction (HFpEF), and left ventricular diastolic dysfunction (LVDD) is a frequent pathophysiological mechanism and specific preclinical manifestation of HFpEF. Therefore, exploring and intervention of the factors associated with risk for LVDD is of great importance in reducing the morbidity and mortality of cardiovascular disease (CVD) complications in CKD patients. We designed this retrospective cross-sectional study to collect clinical and echocardiographic data from 339 nondialysis CKD patients without obvious symptoms of HF to analyze the proportion of asymptomatic left ventricular diastolic dysfunction (ALVDD) and its related factors associated with risk by multivariate logistic regression analysis. Among the 339 nondialysis CKD patients, 92.04% had ALVDD. With the progression of CKD stage, the proportion of ALVDD gradually increased. The multivariate logistic regression analysis revealed that increased age (OR 1.237; 95% confidence interval (CI) 1.108-1.381, per year), diabetic nephropathy (DN) and hypertensive nephropathy (HTN) (OR 25.000; 95% CI 1.355-48.645, DN and HTN vs chronic interstitial nephritis), progression of CKD stage (OR 2.785; 95% CI 1.228-6.315, per stage), increased mean arterial pressure (OR 1.154; 95% CI 1.051-1.268, per mmHg), increased urinary protein (OR 2.825; 95% CI 1.484-5.405, per g/24 h), and low blood calcium (OR 0.072; 95% CI 0.006-0.859, per mmol/L) were factors associated with risk for ALVDD in nondialysis CKD patients after adjusting for other confounding factors. Therefore, dynamic monitoring of these factors associated with risk, timely diagnosis and treatment of ALVDD can delay the progression to symptomatic HF, which is of great importance for reducing CVD mortality, and improving the prognosis and quality of life in CKD patients.

Risk Factors and Outcomes Associated With Heart Failure With Preserved and Reduced Ejection Fraction in People With Chronic Kidney Disease

BACKGROUND

Heart failure (HF) is associated with poor outcomes in people with chronic kidney disease, yet it is unknown whether outcomes differ by HF subtype. This study aimed to examine associations of incident HF with preserved ejection fraction (HFpEF) versus HF with reduced ejection fraction (HFrEF) with progression to end-stage kidney disease (ESKD) and mortality.

METHODS

We studied individuals with chronic kidney disease in the CRIC study (Chronic Renal Insufficiency Cohort) who were free of HF at cohort entry. Incident HF hospitalizations were adjudicated and classified into HFpEF (ejection fraction, ≥50%) or HFrEF (ejection fraction, <50%) based on echocardiograms performed during the hospitalization or at a research study visit. ESKD was defined as need for chronic dialysis or kidney transplant. Cox proportional hazards were used to evaluate the association of time-updated HF subtype with risk of ESKD and mortality, adjusting for demographics, comorbidities, and medication use.

RESULTS

Among the 3557 study participants without HF at cohort entry, mean age was 57 years and mean estimated glomerular filtration rate was 45 mL/min per 1.73 m2. A total of 682 participants had incident HF. Incidence rates for HFpEF and HFrEF were 0.9 (95% CI, 0.8-1.0) and 0.7 (95% CI, 0.6-0.8) per 100 person-years, respectively (Pdifference=0.005). Associations of incident HF with progression to ESKD were not statistically different for HFpEF (hazard ratio, 2.06 [95% CI, 1.66-2.56]) and HFrEF (hazard ratio, 1.80 [95% CI, 1.36-2.38]; P=0.42). The associations with mortality were stronger for HFrEF (hazard ratio, 2.73 [95% CI, 2.24-3.33]) compared with HFpEF (hazard ratio, 1.99 [95% CI, 1.65-2.40]; P=0.0002).

CONCLUSIONS

In a chronic kidney disease population, the rates of HFpEF hospitalizations were greater than that of HFrEF. Risk of ESKD was high but not statically different across HF subtypes. There was a stronger association of HFrEF with mortality. Prevention and treatment of both HFpEF and HFrEF should be central priorities to improve outcomes in chronic kidney disease.

Knowledge landscapes and emerging trends of cardiorenal syndrome type 4: a bibliometrics and visual analysis from 2004 to 2022

PURPOSE

To evaluate the key topics and emerging trends in the field of cardiorenal syndrome type 4 (CRS-4) by bibliometrics and visual analysis.

METHODS

Citespace, VOSviewer, and Bibliometrix package were used to analyze the collected data from the Web of Science Core Collection, including publication trends, leading countries, active authors and institutions, co-cited references, journals, and keyword analysis.

RESULTS

Finally, 2267 articles were obtained. From 2004 to 2022, the number of publications was increasing year by year. A total of 735 authors from 543 institutions in 94 countries/regions participated in the publication of CRS-4 field, which were mostly from North America and Europe. Most of the co-cited references were reviews or guidelines from kidney/heart specialist journals or top journals. The journals concerning nephrology had a higher academic influence in this field. Oxidative stress and inflammation remained hot topics in CRS-4 research, as well as uremic toxins. Fibroblast growth factor 23 and klotho were emerging trends in recent years. Sodium glucose cotransporter 2 (SGLT2) inhibitors were the latest frontier hot spots. Future research advances may pay more attention to the prevention and prognosis assessment of CRS-4.

CONCLUSION

Our study provides some key information for scholars to determine the direction of future research.

Fibroblast Growth Factor 23 and Risk of Heart Failure Subtype: The CRIC (Chronic Renal Insufficiency Cohort) Study

Rationale & Objective

Heart failure (HF) is an important cause of morbidity and mortality among individuals with chronic kidney disease (CKD). A large body of evidence from preclinical and clinical studies implicates excess levels of fibroblast growth factor 23 (FGF23) in HF pathogenesis in CKD. It remains unclear whether the relationship between elevated FGF23 levels and HF risk among individuals with CKD varies by HF subtype.

Study Design

Prospective cohort study.

Settings & Participants

A total of 3,502 participants were selected in the Chronic Renal Insufficiency Cohort study.

Exposure

Baseline plasma FGF23.

Outcomes

Incident HF by subtype and total rate of HF hospitalization. HF was categorized as HF with preserved ejection fraction (HFpEF, ejection fraction [EF] ≥ 50%), HF with reduced EF (HFrEF, EF < 50%) and HF with unknown EF (HFuEF).

Analytical Approach

Multivariable-adjusted cause-specific Cox proportional hazards models were used to investigate associations between FGF23 and incident hospitalizations for HF by subtype. The Lunn-McNeil method was used to compare hazard ratios across HF subtypes. Poisson regression models were used to evaluate the total rate of HF.

Results

During a median follow-up time of 10.8 years, 295 HFpEF, 242 HFrEF, and 156 HFuEF hospitalizations occurred. In multivariable-adjusted cause-specific Cox proportional hazards models, FGF23 was significantly associated with the incidence of HFpEF (HR, 1.41; 95% CI, 1.21-1.64), HFrEF (HR, 1.27; 95% CI, 1.05-1.53), and HFuEF (HR, 1.40; 95% CI, 1.13-1.73) per 1 standard deviation (SD) increase in the natural log of FGF23. The Lunn-McNeil method determined that the risk association was consistent across all subtypes. The rate ratio of total HF events increased with FGF23 quartile. In multivariable-adjusted models, compared with quartile 1, FGF23 quartile 4 had a rate ratio of 1.81 (95% CI, 1.28-2.57) for total HF events.

Limitations

Self-report of HF hospitalizations and possible lack of an echocardiogram at time of hospitalization.

Conclusions

In this large multicenter prospective cohort study, elevated FGF23 levels were associated with increased risks for all HF subtypes.

Plain-Language Summary

Heart failure (HF) is a prominent cause of morbidity and mortality in individuals with chronic kidney disease (CKD). Identifying potential pathways in the development of HF is essential in developing therapies to prevent and treat HF. In a large cohort of individuals with CKD, the Chronic Renal Insufficiency Cohort (N = 3,502), baseline fibroblast growth factor-23 (FGF23), a hormone that regulates phosphorous, was evaluated in relation to the development of incident and recurrent HF with reduced, preserved, and unknown ejection fraction. In this large multicenter prospective cohort study, elevated FGF23 levels were associated with increased risk of all HF subtypes. These findings demonstrate the need for further research into FGF23 as a target in preventing the development of HF in individuals with CKD.

Pre-Heart Failure Longitudinal Change in a Hispanic/Latino Population-Based Study: Insights From the Echocardiographic Study of Latinos

BACKGROUND

Pre-heart failure (pre-HF) is an entity known to progress to symptomatic heart failure (HF).

OBJECTIVES

This study aimed to characterize pre-HF prevalence and incidence among Hispanics/Latinos.

METHODS

The Echo-SOL (Echocardiographic Study of Latinos) assessed cardiac parameters on 1,643 Hispanics/Latinos at baseline and 4.3 years later. Prevalent pre-HF was defined as the presence of any abnormal cardiac parameter (left ventricular [LV] ejection fraction <50%; absolute global longitudinal strain <15%; grade 1 or more diastolic dysfunction; LV mass index >115 g/m2 for men, >95 g/m2 for women; or relative wall thickness >0.42). Incident pre-HF was defined among those without pre-HF at baseline. Sampling weights and survey statistics were used.

RESULTS

Among this study population (mean age: 56.4 years; 56% female), HF risk factors, including prevalence of hypertension and diabetes, worsened during follow-up. Significant worsening of all cardiac parameters (except LV ejection fraction) was evidenced from baseline to follow-up (all P < 0.01). Overall, the prevalence of pre-HF was 66.7% at baseline and the incidence of pre-HF during follow-up was 66.3%. Prevalent and incident pre-HF were seen more with increasing baseline HF risk factor burden as well as with older age. In addition, increasing the number of HF risk factors increased the risk of prevalence of pre-HF and incidence of pre-HF (adjusted OR: 1.36 [95% CI: 1.16-1.58], and adjusted OR: 1.29 [95% CI: 1.00-1.68], respectively). Prevalent pre-HF was associated with incident clinical HF (HR: 10.9 [95% CI: 2.1-56.3]).

CONCLUSIONS

Hispanics/Latinos exhibited significant worsening of pre-HF characteristics over time. Prevalence and incidence of pre-HF are high and are associated with increasing HF risk factor burden and with incidence of cardiac events.

Vitamin D Metabolites and Risk of Cardiovascular Disease in Chronic Kidney Disease: The CRIC Study

Background The ratio of 24,25-dihydroxyvitamin D3/25-hydroxyvitamin D3 (vitamin D metabolite ratio [VDMR]) may reflect functional vitamin D activity. We examined associations of the VDMR, 25-hydroxyvitamin D (25[OH]D), and 1,25-dihydroxyvitamin D (1,25[OH]2D) with cardiovascular disease (CVD) in patients with chronic kidney disease. Methods and Results This study included longitudinal and cross-sectional analyses of 1786 participants from the CRIC (Chronic Renal Insufficiency Cohort) Study. Serum 24,25-dihydroxyvitamin D3, 25(OH)D, and 1,25(OH)2D were measured by liquid chromatography-tandem mass spectrometry 1 year after enrollment. The primary outcome was composite CVD (heart failure, myocardial infarction, stroke, and peripheral arterial disease). We used Cox regression with regression-calibrated weights to test associations of the VDMR, 25(OH)D, and 1,25(OH)2D with incident CVD. We examined cross-sectional associations of these metabolites with left ventricular mass index using linear regression. Analytic models adjusted for demographics, comorbidity, medications, estimated glomerular filtration rate, and proteinuria. The cohort was 42% non-Hispanic White race and ethnicity, 42% non-Hispanic Black race and ethnicity, and 12% Hispanic ethnicity. Mean age was 59 years, and 43% were women. Among 1066 participants without prevalent CVD, there were 298 composite first CVD events over a mean follow-up of 8.6 years. Lower VDMR and 1,25(OH)2D were associated with incident CVD before, but not after, adjustment for estimated glomerular filtration rate and proteinuria (hazard ratio, 1.11 per 1 SD lower VDMR [95% CI, 0.95-1.31]). Only 25(OH)D was associated with left ventricular mass index after full covariate adjustment (0.6 g/m2.7 per 10 ng/mL lower [95% CI, 0.0-1.3]). Conclusions Despite modest associations of 25(OH)D with left ventricular mass index, 25(OH)D, the VDMR, and 1,25(OH)2D were not associated with incident CVD in chronic kidney disease.

The association between changes in echocardiography and risk of heart failure hospitalizations and death in adults with chronic kidney disease

Adults with chronic kidney disease (CKD) are at increased risk for developing heart failure (HF). However, longitudinal cardiac remodeling in CKD has not been well-characterized and its association with HF outcomes remains unknown. We evaluated the association between change in echocardiographic parameters between baseline and year 4 with the subsequent risk of HF hospitalization and death using Cox proportional hazard models in a landmark analysis of a prospective multicenter CKD cohort. Among 2673 participants, mean ± SD age was 61 ± 11 years, with 45% women, and 56% non-white. A total of 472 hospitalizations for HF and 776 deaths occurred during a median (interquartile range) follow-up duration of 8.0 (6.3-9.1) years. Patients hospitalized for HF experienced larger preceding absolute increases in left ventricular (LV) volumes and decreases in LV ejection fraction. Adverse changes in LV ejection fraction, LV cavity volume, LV mass index, and LV geometry were independently associated with an increased risk of HF hospitalization and death. Among adults with CKD, deleterious cardiac remodeling occurs over a relatively short timeframe and adverse remodeling is associated with increased risk of HF-related morbidity and mortality.

Echocardiographic parameters and cardiovascular disease in Japanese- and US-based CKD cohorts

Japanese and US populations have similar chronic kidney disease prevalence but differing clinical outcomes. A secondary analysis compared cardiovascular outcomes in a Japanese- and a US-based chronic kidney disease cohort and found that the US cohort had markedly worse cardiovascular outcomes. Mediation analysis demonstrated that differences in left ventricular structure and function could explain most of the cardiovascular outcome difference. We examine and contextualize this finding and describe implications for precision nephrology and for population health.

Heart Failure-Type Symptom Score Trajectories in CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

RATIONALE & OBJECTIVE

Quality of life in chronic kidney disease (CKD) is impaired by a large burden of symptoms including some that overlap with the symptoms of heart failure (HF). We studied a group of individuals with CKD to understand the patterns and trajectories of HF-type symptoms in this setting.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

3,044 participants in the Chronic Renal Insufficiency Cohort (CRIC) without prior diagnosis of HF.

PREDICTORS

Sociodemographics, medical history, medications, vital signs, laboratory values, echocardiographic and electrocardiographic parameters.

OUTCOME

Trajectory over 5.5 years of a HF-type symptom score (modified Kansas City Cardiomyopathy Questionnaire [KCCQ] Overall Summary Score with a range of 0-100 where<75 reflects clinically significant symptoms).

ANALYTICAL APPROACH

Latent class mixed models were used to model trajectories. Multinomial logistic regression was used to model relationships of predictors with trajectory group membership.

RESULTS

Five trajectories of KCCQ score were identified in the cohort of 3,044 adults, 45% of whom were female, and whose median age was 61 years. Group 1 (41.7%) had a stable high score (minimal symptoms, average score of 96); groups 2 (35.6%) and 3 (15.6%) had stable but lower scores (mild symptoms [average of 81] and clinically significant symptoms [average of 52], respectively). Group 4 (4.9%) had a substantial worsening in symptoms over time (mean 31-point decline), and group 5 (2.2%) had a substantial improvement (mean 33-point increase) in KCCQ score. A majority of group 1 was male, without diabetes or obesity, and this group had higher baseline kidney function. A majority of groups 2 and 3 had diabetes and obesity. A majority of group 4 was male and had substantial proteinuria. Group 5 had the highest proportion of baseline cardiovascular disease (CVD).

LIMITATIONS

No validation cohort available, CKD management changes in recent years may alter trajectories, and latent class models depend on the missing at random assumption.

CONCLUSIONS

Distinct HF-type symptom burden trajectories were identified in the setting of CKD, corresponding to different baseline characteristics. These results highlight the diversity of HF-type symptom experiences in individuals with CKD.

Clinical impact of left ventricular systolic dysfunction in patients undergoing dialysis access surgery

BACKGROUND

An arteriovenous fistula (AVF) is the most frequently used dialysis access for haemodialysis. However, it can cause volume loading for the heart and may induce circulatory failure when performed in patients with low cardiac function. This study aimed to characterise patients with low cardiac function when initiating dialysis and determine how cardiac function changes after the dialysis access surgery.

METHODS

We conducted a retrospective observational study at two centres incorporating 356 patients with end-stage kidney disease who underwent echocardiography before the dialysis access surgery.

RESULTS

An AVF and a subcutaneously fixed superficial artery were selected in 70.4% and 23.5% of 81 patients with reduced/mildly reduced (< 50%) left ventricular ejection fraction (LVEF), respectively, and in 94.2% and 1.1% of 275 patients with preserved (≥ 50%) LVEF (p < 0.001), respectively. Follow-up echocardiography was performed in 70.4% and 38.2% of patients with reduced/mildly reduced and preserved LVEF, respectively, which showed a significant increase in LVEF (41 ± 9-44 ± 12%, p = 0.038) in patients with reduced/mildly reduced LVEF. LVEF remained unchanged in 12 patients with reduced/mildly reduced LVEF who underwent subcutaneously fixed superficial artery (30 ± 10-32 ± 15%, p = 0.527). Patients with reduced/mildly reduced LVEF had lower survival rates after surgery than those with preserved LVEF (p = 0.021 for log-rank).

CONCLUSION

The LVEF subcategory was associated with dialysis access selection. After the dialysis access surgery, LVEF was increased in patients with reduced/mildly reduced LVEF. These results may help select dialysis access for patients initiating dialysis.

Diastolic dysfunction is an independent predictor for cardiovascular events after an acute kidney injury

BACKGROUND AND AIM

Acute kidney injury (AKI) conditions several short- and long-term complications. The aim of the present study was to analyse the impact of cardiac function and structure in the cardiovascular prognosis after an in-hospital AKI episode.

MATERIAL AND METHODS

This is an observational retrospective cohorts study including all in-hospital AKI episodes in 2013 and 2014 in our centre. At baseline, epidemiological values, comorbidities and echocardiography parameters were collected. During a follow-up of 49 ± 28 months, cardiovascular events (CVE) were collected, and associated factors were analysed.

RESULTS

1255 patients were included (55% male, age 75 ± 13 years). Of the 676 (54%) that had a previous echocardiogram, 46% had left ventricular hypertrophy, 38% pulmonary hypertension, 38% diastolic dysfunction and 22% systolic dysfunction. During the follow-up, 484 (39%) developed a CVE. Associated factors to VCE were male sex, age, diabetes mellitus, hypertension, dyslipidemia, coronary heart disease, heart failure, atrial fibrillation, neoplasia and chronic kidney disease (also, glomerular filtration rate at baseline and after the AKI episode). Survival curves demonstrated that all the echocardiographic parameters were associated to CVE. An adjusted Cox regression model showed that age (HR 1.017), diabetes (HR 1.576) and diastolic dysfunction (HR 1.358) were independent predictors for CVE.

CONCLUSION

Diastolic dysfunction is an independent predictor for long-term cardiovascular events after an in-hospital acute kidney injury episode.

Deep Learning Using Electrocardiograms in Patients on Maintenance Dialysis

Cardiovascular morbidity and mortality occur with an extraordinarily high incidence in the hemodialysis-dependent end-stage kidney disease population. There is a clear need to improve identification of those individuals at the highest risk of cardiovascular complications in order to better target them for preventative therapies. Twelve-lead electrocardiograms are ubiquitous and use inexpensive technology that can be administered with minimal inconvenience to patients and at a minimal burden to care providers. The embedded waveforms encode significant information on the cardiovascular structure and function that might be unlocked and used to identify at-risk individuals with the use of artificial intelligence techniques like deep learning. In this review, we discuss the experience with deep learning-based analysis of electrocardiograms to identify cardiovascular abnormalities or risk and the potential to extend this to the setting of dialysis-dependent end-stage kidney disease.

Heart failure-type symptom scores in chronic kidney disease: The importance of body mass index

OBJECTIVES

This analysis sought to determine factors (including adiposity-related factors) most associated with HF-type symptoms (fatigue, shortness of breath, and edema) in adults with chronic kidney disease (CKD).

BACKGROUND

Symptom burden impairs quality of life in CKD, especially symptoms that overlap with HF. These symptoms are common regardless of clinical HF diagnosis, and may be affected by subtle cardiac dysfunction, kidney dysfunction, and other factors. We used machine learning to investigate cross-sectional relationships of clinical variables with symptom scores in a CKD cohort.

METHODS

Participants in the Chronic Renal Insufficiency Cohort (CRIC) with a baseline modified Kansas City Cardiomyopathy Questionnaire (KCCQ) score were included, regardless of prior HF diagnosis. The primary outcome was Overall Summary Score as a continuous measure. Predictors were 99 clinical variables representing demographic, cardiac, kidney and other health dimensions. A correlation filter was applied. Random forest regression models were fitted. Variable importance scores and adjusted predicted outcomes are presented.

RESULTS

The cohort included 3426 individuals, 10.3% with prior HF diagnosis. BMI was the most important factor, with BMI 24.3 kg/m2 associated with the least symptoms. Symptoms worsened with higher or lower BMIs, with a potentially clinically relevant 5 point score decline at 35.7 kg/m2 and a 1-point decline at the threshold for low BMI, 18.5 kg/m2. The most important cardiac and kidney factors were heart rate and eGFR, the 4th and 5th most important variables, respectively. Results were similar for secondary analyses.

CONCLUSIONS

In a CKD cohort, BMI was the most important feature for explaining HF-type symptoms regardless of clinical HF diagnosis, identifying an important focus for symptom directed investigations.

Automated Determination of Left Ventricular Function Using Electrocardiogram Data in Patients on Maintenance Hemodialysis

BACKGROUND AND OBJECTIVES

Left ventricular ejection fraction is disrupted in patients on maintenance hemodialysis and can be estimated using deep learning models on electrocardiograms. Smaller sample sizes within this population may be mitigated using transfer learning.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We identified patients on hemodialysis with transthoracic echocardiograms within 7 days of electrocardiogram using diagnostic/procedure codes. We developed four models: (1) trained from scratch in patients on hemodialysis, (2) pretrained on a publicly available set of natural images (ImageNet), (3) pretrained on all patients not on hemodialysis, and (4) pretrained on patients not on hemodialysis and fine-tuned on patients on hemodialysis. We assessed the ability of the models to classify left ventricular ejection fraction into clinically relevant categories of ≤40%, 41% to ≤50%, and >50%. We compared performance by area under the receiver operating characteristic curve.

RESULTS

We extracted 705,075 electrocardiogram:echocardiogram pairs for 158,840 patients not on hemodialysis used for development of models 3 and 4 and n=18,626 electrocardiogram:echocardiogram pairs for 2168 patients on hemodialysis for models 1, 2, and 4. The transfer learning model achieved area under the receiver operating characteristic curves of 0.86, 0.63, and 0.83 in predicting left ventricular ejection fraction categories of ≤40% (n=461), 41%-50% (n=398), and >50% (n=1309), respectively. For the same tasks, model 1 achieved area under the receiver operating characteristic curves of 0.74, 0.55, and 0.71, respectively; model 2 achieved area under the receiver operating characteristic curves of 0.71, 0.55, and 0.69, respectively, and model 3 achieved area under the receiver operating characteristic curves of 0.80, 0.51, and 0.77, respectively. We found that predictions of left ventricular ejection fraction by the transfer learning model were associated with mortality in a Cox regression with an adjusted hazard ratio of 1.29 (95% confidence interval, 1.04 to 1.59).

CONCLUSION

A deep learning model can determine left ventricular ejection fraction for patients on hemodialysis following pretraining on electrocardiograms of patients not on hemodialysis. Predictions of low ejection fraction from this model were associated with mortality over a 5-year follow-up period.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2022_06_06_CJN16481221.mp3.

Prediction of Incident Heart Failure in CKD: The CRIC Study

Introduction

Heart failure (HF) is common in chronic kidney disease (CKD); identifying patients with CKD at high risk for HF may guide clinical care. We assessed the prognostic value of cardiac biomarkers and echocardiographic variables for 10-year HF prediction compared with a published clinical HF prediction equation in a cohort of participants with CKD.

Methods

We studied 2147 Chronic Renal Insufficiency Cohort (CRIC) participants without prior HF with complete clinical, cardiac biomarker (N-terminal brain natriuretic peptide [NT-proBNP] and high sensitivity troponin-T [hsTnT]), and echocardiographic data (left ventricular mass [LVM] and left ventricular ejection fraction [LVEF] data). We compared the discrimination of the 11-variable Atherosclerosis Risk in Communities (ARIC) HF prediction equation with LVM, LVEF, hsTnT, and NT-proBNP to predict 10-year risk of hospitalization for HF using a Fine and Gray modeling approach. We separately evaluated prediction of HF with preserved and reduced LVEF (LVEF ≥50% and <50%, respectively). We assessed discrimination with internally valid C-indices using 10-fold cross-validation.

Results

Participants' mean (SD) age was 59 (11) years, 53% were men, 43% were Black, and mean (SD) estimated glomerular filtration rate (eGFR) was 44 (16) ml/min per 1.73 m2. A total of 324 incident HF hospitalizations occurred during median (interquartile range) 10.0 (5.7-10.0) years of follow-up. The ARIC HF model with clinical variables had a C-index of 0.68. Echocardiographic variables predicted HF (C-index 0.70) comparably to the published ARIC HF model, while NT-proBNP and hsTnT together (C-index 0.73) had significantly better discrimination (P = 0.004). A model including cardiac biomarkers, echocardiographic variables, and clinical variables had a C-index of 0.77. Discrimination of HF with preserved LVEF was lower than for HF with reduced LVEF for most models.

Conclusion

The ARIC HF prediction model for 10-year HF risk had modest discrimination among adults with CKD. NT-proBNP and hsTnT discriminated better than the ARIC HF model and at least as well as a model with echocardiographic variables. HF clinical prediction models tailored to adults with CKD are needed. Until then, measurement of NT-proBNP and hsTnT may be a low-burden approach to predicting HF in this population, as they offer moderate discrimination.

Mortality Trends after Transfer from Peritoneal Dialysis to Hemodialysis

Introduction

Transition to hemodialysis (HD) is a common outcome in peritoneal dialysis (PD), but the associated mortality risk is poorly understood. This study sought to identify rates of and risk factors for mortality after transitioning from PD to HD.

Methods

Patients with incident PD (between 2000 and 2014) who transferred to HD for ≥1 day were identified, using data from Australia and New Zealand Dialysis and Transplantation registry (ANZDATA), Canadian Organ Replacement Register (CORR), Europe Renal Association (ERA) Registry, and the United States Renal Dialysis System (USRDS). Crude mortality rates were calculated for the first 180 days after transfer. Separate multivariable Cox models were built for early (<90 days), medium (90–180 days), and late (>180 days) periods after transfer.

Results

Overall, 6683, 5847, 21,574, and 80,459 patients were included from ANZDATA, CORR, ERA Registry, and USRDS, respectively. In all registries, crude mortality rate was highest during the first 30 days after a transfer to HD declining thereafter to nadir at 4 to 6 months. Crude mortality rates were lower for patients transferring in the most recent years (than earlier). Older age, PD initiation in earlier cohorts, and longer PD vintage were associated with increased risk of death, with the strongest associations during the first 90 days after transfer and attenuating thereafter. Mortality risk was lower for men than women <90 days after transfer, but higher after 180 days.

Conclusion

In this multinational study, mortality was highest in the first month after a transfer from PD to HD and risk factors varied by time period after transfer. This study highlights the vulnerability of patients at the time of modality transfer and the need to improve transitions.

3D Echocardiography - A Useful Method for Cardiovascular Risk Assessment in End-Stage Renal Disease Patients

Patients with chronic kidney disease (CKD) have an increased risk of premature mortality, mainly due to cardiovascular causes. The association between hemodialysis and accelerated atherosclerosis has long been described. The ankle-brachial index (ABI) is a surrogate marker of atherosclerosis and recent studies indicate its utility as a predictor of future cardiovascular disease and all-cause mortality. The clinical implications of ABI cut-points are not well defined in patients with CKD. Echocardiography is the most widely used imaging method for cardiac evaluation. Structural and functional myocardial abnormalities are common in patients with CKD due to pressure and volume overload as well as non-hemodynamic factors associated with CKD. Our study aimed to identify markers of subclinical cardiovascular risk assessed using ABI and 2D and 3D echocardiographic parameters evaluating left ventricular (LV) structure and function in patients with end-stage renal disease (ESRD) (patients undergoing dialysis), patients after kidney transplantation and non-ESRD patients (control). In ESRD, particularly in hemodialysis patients, changes in cardiac structure, rather than function, seems to be more pronounced. 3D echocardiography appears to be more sensitive than 2D echocardiography in the assessment of myocardial structure and function in CKD patients. Particularly 3D derived end-diastolic volume and 3D derived LV mass indexed for body surface appears to deteriorate in dialyzed and transplanted patients. In 2D echocardiography, myocardial mass represented by left ventricular mass/body surface area index (LVMI) appears to be a more sensitive marker of cardiac structural changes, compared to relative wall thickness (RWT), left ventricle and diastolic diameter index (LVEDDI) and left atrial volume index (LAVI). We observed a generally favorable impact of kidney transplantation on cardiac structure and function; however, the differences were non-significant. The improvement seems to be more pronounced in cardiac function parameters, peak early diastolic velocity/average peak early diastolic velocity of mitral valve annulus (E/e´), 3D left ventricle ejection fraction (LV EF) and global longitudinal strain (GLS). We conclude that ABI is not an appropriate screening test to determine the cardiovascular risk in patients with ESRD.

Left atrial strain: A novel "biomarker" for chronic kidney disease patients?

Cardiovascular disease and chronic kidney disease are frequently inter-connected and this association leads to an exponential growth of cardiovascular risk. This risk is currently underestimated by the existing algorithms and there is a constant need for new markers to predict adverse outcomes in this special population. In general population left atrial strain has emerged as an important tool for both the diagnosis and prognostic stratification, but data regarding its role in chronic kidney disease patients is scarce. The purpose of this review is to summarize the current evidence regarding this matter. Left atrial size and function mirror the duration and severity of increased left ventricular filling pressures. Increased left atrial volume index and impaired left atrial strain parameters are independent predictors for adverse cardiovascular events. Left atrial strain is impaired before changes in volume appear, thus being able to predict both diastolic and systolic function in chronic kidney disease patients. Finally, left atrial strain can identify renal patients with impaired exercise capacity and this could have clinical applications in the rehabilitation of this patients.

A longitudinal study of cardiac structure and function using echocardiography in patients undergoing peritoneal dialysis

Background

Peritoneal dialysis (PD) can be associated with abnormal cardiac structure and function and increased mortality risk. Therefore, in this study, we analyzed the cardiac structure and function dynamic changes using echocardiography during the first 2 years of PD therapy. We also assessed its associations with all-cause mortality risk after 2 years of follow-up.

Methods

End-stage renal disease (ESRD) patients that have started PD from 2011 to 2017, and had echocardiography at baseline and years 1 and 2, were included in this study. Echocardiographic parameters were compared between baseline and year 2. Multivariable Cox models were used to estimate the association between echocardiographic parameters changes and all-cause mortality risk.

Results

We finally enrolled 72 PD patients in this study. The mean right ventricular diameter (RVD) increased from baseline (18.31 mm) to year 1 (18.75 mm) and year 2 (19.65 mm). We also observed a significant decrease in cardiac output (CO) between baseline and year 2. Additionally, a slight decrease trend in ejection fraction (EF) was observed. Finally, every 1 % increase in RVD was associated with a 68.2 % higher mortality risk after dialysis (HR, 1.682; 95 % CI, 1.017–2.783).

Conclusions

Our results demonstrated a susceptibility for deteriorated right cardiac structure and function during the first 2 years of PD treatment. Also, higher all-cause mortality risk was observed after 2 years of PD. Altogether, these results highlighted the need for additional focus on regular echocardiographic examinations during long-term PD management.

Trial registration

The PD-CRISC cohort, registered with the Chinese Clinical Trial Registry (ChiCTR1900023565).

Aortic Root Dilatation Is Attenuated with Diabetes but Is Not Associated with Renal Progression in Chronic Kidney Disease

Patients with chronic kidney disease (CKD) often have cardiac functional and structural abnormalities which can lead to adverse cardiovascular outcomes. In this study, we investigated associations between diabetes mellitus (DM) and cardiac functional and structural parameters in patients with CKD focusing on aortic root diameter (ARD). We also investigated associations of renal outcomes with DM and cardiac functional and structural characteristics. We enrolled 419 patients with CKD stage 3–5 were enrolled. ARD was normalized to body surface area (BSA) (ARD/BSA), and the rate of decline in renal function was assessed by the estimated glomerular filtration rate (eGFR) slope (mL/min/1.73 m²/year). ARD/BSA ≥2.1 cm/m² in men or ≥2.2 cm/m² in women was defined as indicating aortic root dilatation. The patients with DM had lower ARD/BSA, higher left atrial dimension (LAD), lower left ventricular ejection fraction, lower ratio of peak early transmitral filling wave velocity to peak late transmitral filling wave velocity, and higher left ventricular relative wall thickness, than those without DM. After multivariable analysis, DM (vs. non-DM; coefficient β, −0.060; p = 0.018) was significantly associated with low ARD/BSA. Significantly fewer patients with DM had aortic root dilatation compared to those without DM (14.3% vs. 23.1%, p = 0.022). In the patients with DM, there were significant associations between a high left ventricular mass index (LVMI) (per 1 g/m², β, −0.016; p = 0.040) and high LAD (per 1 cm; β, −1.965; p < 0.001) with a low eGFR slope. However, other parameters, including ARD/BSA, were not associated with eGFR slope. Furthermore, there were no associations between eGFR slope and any of the echocardiographic parameters in the patients without DM. Aortic root dilatation was attenuated in the patients with DM, but it was not associated with a decline in renal function. However, high LAD and LVMI were associated with rapid renal function decline in the CKD patients with DM.

Disparate Information Provided by Pulse Wave Velocity versus Other Measures of Aortic Compliance in End-Stage Renal Disease

INTRODUCTION

Unfavorable changes in cardiac and arterial function are related to poor prognosis in chronic kidney disease (CKD). We compared hemodynamic profiles between subjects with end-stage renal disease and 2 control groups with corresponding pulse wave velocities (PWVs).

METHODS

Noninvasive hemodynamics were recorded during passive head-up tilt in CKD stage 5 patients (n = 35), patients with primary hypertension (n = 35, n = 30 with antihypertensive medications), and subjects without cardiovascular or renal diseases and cardiovascular medications (n = 70). The groups were selected to have corresponding age, sex, body mass index, and PWV. Hemodynamic data were captured using whole-body impedance cardiography and radial tonometric pulse wave analysis.

RESULTS

Supine blood pressure did not differ between the groups, but upright diastolic blood pressure was lower in CKD patients than in the 2 control groups (p ≤ 0.001 for both, RANOVA). Despite similar PWV, supine aortic pulse pressure was higher in CKD patients versus nonmedicated subjects (p = 0.029). Two additional measures indicated reduced aortic compliance in CKD patients versus both control groups: lower ratio of stroke index to aortic pulse pressure (p ≤ 0.023) and higher aortic characteristic impedance (p ≤ 0.003). The subendocardial viability ratio was lower in the CKD group than in both control groups (p ≤ 0.039).

CONCLUSION

In the absence of differences in PWV, higher aortic pulse pressure and characteristic impedance, and lower ratio of stroke index to aortic pulse pressure, suggest reduced aortic compliance and impaired left ventricular function in CKD patients. A lower subendocardial viability ratio predisposes the CKD patients to impaired cardiac oxygen supply versus hypertensive patients and nonmedicated controls.

Clinical Assistant Analysis of Color Doppler Ultrasound in Diagnosis Parameters of Chronic Heart Failure

Chronic heart failure (CHF) is a group of clinical syndromes caused by changes in myocardial structure and function caused by any reason, leading to ventricular filling and ejection disorders. It is the final stage of the development of various cardiovascular diseases. It is a progressive disease. Once it starts, even if there is no new myocardial damage, the clinic is still in a stable stage, and it can still continue to develop on its own. This article uses the comprehensive parameters of echocardiography to evaluate the overall heart function of patients with chronic heart failure, and evaluates the treatment effect of patients with chronic heart failure. A total of 160 patients with chronic heart failure were studied, including 80 cases in the follow-up group, 40 cases in the non-follow-up group, and 40 cases in the normal control group. The heart failure ultrasound index composed of the comprehensive parameters of echocardiography was used to measure brain natriureric pepride (BNP), and the heart function was graded. The results showed that when the heart failure ultrasound index value >3, the diagnosis of symptomatic chronic heart failure had a sensitivity of 94.7%, a specificity of 94.6%, a positive predictive value of 97.8%, and a negative predictive value of 80.6%. The heart failure ultrasound index was positively correlated with plasma BNP and NYHA heart function (respectively 0.68, 0.73). After 6 months of observation, the ultrasound index of heart failure in the follow-up group decreased significantly before and after treatment. The experimental results show that the heart failure ultrasound index can be used to guide the treatment of patients with chronic heart failure, evaluate the treatment effect, and evaluate the prognosis. Appropriate health education and standardized medication can improve the treatment effect of chronic heart failure and improve the quality of life of patients.

Quality of Life Is Associated with Cardiac Biomarkers, Echocardiographic Indices, and Mortality in CKD Stage 4-5 Patients Not on Dialysis

INTRODUCTION

Patients with CKD have an impaired health-related quality of life (QoL). Most studies have been conducted on dialysis patients, and less is known about QoL and its determinants in predialysis patients. We studied the association between QoL and comorbidities, cardiac biomarkers, echocardiography, and mortality in patients with CKD stage 4-5 not on dialysis.

METHODS

A total of 140 patients enrolled in the Chronic Arterial Disease, Quality of Life and Mortality in Chronic Kidney Injury (CADKID) study filled the Kidney Disease Quality of Life Short Form (KDQOL-SF) at the beginning of the study. Echocardiography and biochemical parameters were obtained at baseline. Patients were followed up for at least 2 years or until death.

RESULTS

The median age was 66 years, and 51 (36%) patients were female. The median estimated glomerular filtration rate was 13 mL/min per 1.73 m2. Obesity, diabetes, atrial fibrillation, and congestive heart failure were associated with lower QoL scores in multiple KDQOL-SF domains. Cardiac biomarkers, troponin T (p = 0.02), N-terminal pro-B-type natriuretic peptide (p = 0.006), and the echocardiographic parameter of cardiac systolic function left ventricular global longitudinal strain (p = 0.02) were significant predictors of lower physical component summary (PCS) score in multivariable regression models after controlling for age, BMI, and diabetes. A low PCS score predicted mortality in a multivariable Cox proportional hazards model [HR 0.96 (95% CI 0.92-0.99), p = 0.03]. QoL was not associated with kidney disease progression.

CONCLUSION

Impaired QoL in CKD stage 4-5 patients not on dialysis is associated with cardiac biomarker levels, echocardiographic indices, and mortality.

Cardiac Imaging in Dialysis Patients

There is a well-established yet unexplained high prevalence of cardiovascular morbidity and mortality in individuals with end-stage kidney disease receiving dialysis. Potential causes include changes in cardiac structure and function, with increased left ventricular mass index as the best established cardiac structural change associated with this increase in mortality. However, in recent years, new echocardiographic and cardiac magnetic resonance imaging techniques have emerged that may provide novel markers that may better explain the mechanisms underlying the cardiovascular morbidity and mortality observed in end-stage kidney disease. This review outlines advances in cardiac imaging and the current status of imaging modalities, including echocardiography, cardiac magnetic resonance imaging, and cardiac positron emission tomography, to identify dialysis patients at high risk for cardiovascular mortality.

Left-sided heart disease and risk of death in patients with end-stage kidney disease receiving haemodialysis: an observational study

BACKGROUND

Cardiovascular disease is the most common cause of death in patients with end-stage kidney disease on haemodialysis. The potential clinical consequence of systematic echocardiographic assessment is however not clear. In an unselected, contemporary population of patients on maintenance haemodialysis we aimed to assess: the prevalence of structural and functional heart disease, the potential therapeutic consequences of echocardiographic screening and whether left-sided heart disease is associated with prognosis.

METHODS

Adult chronic haemodialysis patients in two large dialysis centres had transthoracic echocardiography performed prior to dialysis and were followed prospectively. Significant left-sided heart disease was defined as moderate or severe left-sided valve disease or left ventricular ejection fraction (LVEF) ≤40%.

RESULTS

Among the 247 included patients (mean 66 years of age [95%CI 64-67], 68% male), 54 (22%) had significant left-sided heart disease. An LVEF ≤40% was observed in 31 patients (13%) and severe or moderate valve disease in 27 (11%) patients. The findings were not previously recognized in more than half of the patients (56%) prior to the study. Diagnosis had a potential impact on management in 31 (13%) patients including for 18 (7%) who would benefit from initiation of evidence-based heart failure therapy. After 2.8 years of follow-up, all-cause mortality among patients with and without left-sided heart disease was 52 and 32% respectively (hazard ratio [HR] 1.95 (95%CI 1.25-3.06). A multivariable adjusted Cox proportional hazard analysis showed that left-sided heart disease was an independent predictor of mortality with a HR of 1.60 (95%CI 1.01-2.55) along with age (HR per year 1.05 [95%CI 1.03-1.07]).

CONCLUSION

Left ventricular systolic dysfunction and moderate to severe valve disease are common and often unrecognized in patients with end-stage kidney failure on haemodialysis and are associated with a higher risk of death. For more than 10% of the included patients, systematic echocardiographic assessment had a potential clinical consequence.

Cardiovascular Determinants of Mortality in Advanced Chronic Kidney Disease

BACKGROUND

Patients with advanced chronic kidney disease (CKD stage 4-5) have an increased risk of death. To study the determinants of all-cause mortality, we recruited 210 consecutive CKD stage 4-5 patients not on dialysis to the prospective Chronic Arterial Disease, quality of life and mortality in chronic KIDney injury (CADKID) study.

METHODS

One hundred seventy-four patients underwent maximal bicycle ergometry stress testing and lateral lumbar radiography to study abdominal aortic calcification score and echocardiography. Carotid and femoral artery intima-media thickness and elasticity and brachial artery flow-mediated dilatation were measured in 156 patients.

RESULTS

The duration of follow-up was 42 ± 17 months (range 134-2,217 days). The mean age was 61 ± 14 years, and the estimated glomerular filtration rate was 12 (11-15) mL/min/1.73 m2. Thirty-six (21%) patients died during follow-up (time to death 835 ± 372 days). Seventy-five and 21 patients had diabetes and coronary artery disease, respectively, and all but one had hypertension. In the respective multivariate proportional hazards models adjusted for age, sex, and coronary artery disease, the significant determinants of mortality were troponin T, N-terminal pro-B-type natriuretic peptide, maximal ergometry performance, abdominal aortic calcification score, E/e' ratio, and albumin.

CONCLUSION

Stress ergometry performance, abdominal aortic calcification score, E/e' of echocardiography, and plasma cardiac biomarkers and albumin predict mortality in advanced CKD.

Longitudinal changes of left and right cardiac structure and function in patients with end-stage renal disease on replacement therapy

BACKGROUND

Few data are available regarding longitudinal changes of cardiac structure and function in end-stage chronic kidney disease (CKD). Aim of the present study is to describe serial echocardiographic findings in a cohort of dialyzed CKD patients.

METHODS

In this retrospective longitudinal study, we included n = 120 dialyzed CKD patients who underwent at least 2 echocardiograms either 1, 2 or 3 years apart. After baseline echocardiogram, n = 112 had a further examination at year 1, n = 76 at year 2 and n = 45 at year 3. Echocardiographic examination included Tissue Doppler Imaging of both left (LV) and right (RV) ventricle.

RESULTS

LV geometry and LV mass index did not significantly change over time. RV progressively dilated (mean change +1.3 mm, +1.1 mm and +3.1 mm at year 1, 2 and 3 respectively, p = 0.002, adjusted p = 0.003). Tissue Doppler parameters showed significant changes with regard to both LV (mean change of E/E' +0.7, +1.3, +1.7 at year 1, 2 and 3 respectively p<0.001, adjusted p = 0.079) and RV (mean change of S wave (cm/sec) -1, -1.7, -2 at year 1, 2 and 3 respectively, p <0.001, adjusted p = 0.041). Decrease of RV S wave negatively correlated with E/E' changes (r=-0.303, p = 0.002; r=-0.246, p = 0.049; r=-0.265, p = 0.089; at year 1, 2 and 3 respectively). LV ejection fraction (LVEF) progressively declined (p = 0.034, adjusted p = 0.140), albeit being significant lower against baseline only at year 3 (mean change -4.3%, p<0.05).

CONCLUSIONS

In dialyzed CKD patients we observed parallel worsening of LV diastolic and RV systolic function accompanied by RV dilation. LVEF decreased less sharply.

Associations Between Cardiac Biomarkers and Cardiac Structure and Function in CKD

Introduction

Subclinical changes to cardiac structure and function detected with echocardiography precede the development of clinical heart failure (HF) in persons with chronic kidney disease (CKD). Circulating cardiac biomarkers may reflect these pathophysiological changes. This study investigated associations between established biomarkers (N-terminal pro-B-type natriuretic peptide [NT-proBNP] and high-sensitivity troponin T [hsTnT]) and novel biomarkers (growth differentiation factor 15 [GDF-15], galectin-3 [Gal-3], and soluble ST-2 [sST-2]), using echocardiographic measurements in persons with CKD.

Methods

In cross-sectional analyses among 2101 participants with mild to moderate CKD in the Chronic Renal Insufficiency Cohort (CRIC), biomarker levels measured at baseline were evaluated with echocardiographic measurements 1 year later. These included left ventricular mass index (LVMI), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), left ventricular ejection fraction (LVEF), and left atrial diameter (LAD). Multivariable linear regression analyses tested associations of each biomarker with echocardiographic measurements, adjusting for covariates.

Results

GDF-15 was significantly associated with higher LVMI (1.0 g/m^2.7; 95% CI, 0.4–1.7), LVESV (0.4 ml/m^2.7; 95% CI, 0.0–0.7), and LVEDV (0.6 ml/m^2.7; 95% CI, 0.1–1.1), but not with LVEF or LAD. These findings were not significant when adjusting for NT-proBNP and hsTnT. Gal-3 and sST-2 had no significant associations. Higher levels of NT-proBNP and hsTnT were associated with all echocardiographic measurements.

Conclusion

In patients with CKD, the novel biomarker GDF-15, a marker of inflammation and tissue injury, and clinical biomarkers NT-proBNP and hsTnT, were associated with echocardiographic measurements of subclinical cardiovascular disease. Collectively, these biomarkers may highlight biological pathways that contribute to the development of clinical HF.

Burden and Outcomes of Heart Failure Hospitalizations in Adults With Chronic Kidney Disease

BACKGROUND

Data on rates of heart failure (HF) hospitalizations, recurrent hospitalizations, and outcomes related to HF hospitalizations in chronic kidney disease (CKD) are limited.

OBJECTIVES

This study examined rates of HF hospitalizations and re-hospitalizations within a large CKD population and evaluated the burden of HF hospitalizations with the risk of subsequent CKD progression and death.

METHODS

The prospective CRIC (Chronic Renal Insufficiency Cohort) study measured the estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (ACR) at baseline. The crude rates and rate ratios of HF hospitalizations and 30-day HF re-hospitalizations were calculated using Poisson regression models. Cox regression was used to assess the association of the frequency of HF hospitalizations within the first 2 years of follow-up with risk of subsequent CKD progression and death.

RESULTS

Among 3,791 participants, the crude rate of HF admissions was 5.8 per 100 person-years (with higher rates of HF with preserved ejection fraction vs. HF with reduced ejection fraction). The adjusted rate of HF was higher with a lower eGFR (vs. eGFR >45 ml/min/1.73 m²); the rate ratios were 1.7 and 2.2 for eGFR 30 to 44 and <30 ml/min/1.73 m² (vs. >45 ml/min/1.73 m²), respectively. Similarly, the adjusted rates of HF hospitalization were significantly higher in those with higher urine ACR (vs. urine ACR <30 mg/g); the rate ratios were 1.9 and 2.6 for urine ACR 30 to 299 and ≥300 mg/g, respectively. Overall, 20.6% of participants had a subsequent HF re-admission within 30 days. HF hospitalization within 2 years of study entry was associated with greater adjusted risks for CKD progression (1 hospitalization: hazard ratio [HR]: 1.93; 95% confidence interval [CI]: 1.40 to 2.67; 2+ hospitalizations: HR: 2.14; 95% CI: 1.30 to 3.54) and all-cause death (1 hospitalization: HR: 2.20; 95% CI: 1.71 to 2.84; 2+ hospitalizations: HR: 3.06; 95% CI: 2.23 to 4.18).

CONCLUSIONS

Within a large U.S. CKD population, the rates of HF hospitalizations and re-hospitalization were high, with even higher rates across categories of lower eGFR and higher urine ACR. Patients with CKD hospitalized with HF had greater risks of CKD progression and death. HF prevention and treatment should be a public health priority to improve CKD outcomes.

Association Between Renal Function and Troponin T Over Time in Stable Chronic Kidney Disease Patients

Background

People with reduced glomerular filtration rate (GFR) often have elevated cardiac troponin T (cTnT) levels. It remains unclear how cTnT levels develop over time in those with chronic kidney disease (CKD). The aim of this study was to prospectively study the association between cTnT and GFR over time in older advanced‐stage CKD patients not on dialysis.

Methods and Results

The EQUAL (European Quality Study) study is an observational prospective cohort study in stage 4 to 5 CKD patients aged ≥65 years not on dialysis (incident estimated GFR, <20 mL/min/1.73 m²). The EQUAL cohort used for the purpose of this study includes 171 patients followed in Sweden between April 2012 and December 2018. We used linear mixed models, adjusted for important groups of confounders, to investigate the effect of both measured GFR and estimated GFR on high‐sensitivity cTnT (hs‐cTnT) trajectory over 4 years. Almost all patients had at least 1 hs‐cTnT measurement elevated above the 99th percentile of the general reference population (≤14 ng/L). On average, hs‐cTnT increased by 16%/year (95% CI, 13–19; P<0.0001). Each 15 mL/min/1.73 m² lower mean estimated GFR was associated with a 23% (95% CI, 14–31; P<0.0001) higher baseline hs‐cTnT and 9% (95% CI, 5–13%; P<0.0001) steeper increase in hs‐cTnT. The effect of estimated GFR on hs‐cTnT trajectory was somewhat lower than a previous myocardial infarction (15%), but higher than presence of diabetes mellitus (4%) and male sex (5%).

Conclusions

In CKD patients, hs‐cTnT increases over time as renal function decreases. Lower CKD stage (each 15 mL/min/1.73 m² lower) is independently associated with a steeper hs‐cTnT increase over time in the same range as other established cardiovascular risk factors.

Cardiac Biomarkers and Risk of Incident Heart Failure in Chronic Kidney Disease: The CRIC (Chronic Renal Insufficiency Cohort) Study

Background

Cardiac biomarkers may signal mechanistic pathways involved in heart failure (HF), a leading complication in chronic kidney disease. We tested the associations of NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide), high‐sensitivity troponin T (hsTnT), galectin‐3, growth differentiation factor‐15 (GDF‐15), and soluble ST2 (sST2) with incident HF in chronic kidney disease.

Methods and Results

We examined adults with chronic kidney disease enrolled in a prospective, multicenter study. All biomarkers were measured at baseline. The primary outcome was incident HF. Secondary outcomes included HF with preserved ejection fraction (EF≥50%) and reduced ejection fraction (EF<50%). Cox models were used to test the association of each cardiac biomarker with HF, adjusting for demographics, kidney function, cardiovascular risk factors, and medication use. Among 3314 participants, all biomarkers, with the exception of galectin‐3, were significantly associated with increased risk of incident HF (hazard ratio per SD higher concentration of log‐transformed biomarker): NT‐proBNP (hazard ratio, 2.07; 95% CI, 1.79–2.39); hsTnT (hazard ratio, 1.38; 95% CI, 1.21–1.56); GDF‐15 (hazard ratio, 1.44; 95% CI, 1.26–1.66) and sST2 (hazard ratio, 1.19; 95% CI, 1.05–1.35). Higher NT‐proBNP, hsTnT, and GDF‐15 were also associated with a greater risk of HF with reduced EF; while higher NT‐proBNP GDF‐15 and sST2 were associated with HF with preserved EF. Galectin‐3 was not associated with either HF with reduced EF or HF with preserved EF.

Conclusions

In chronic kidney disease, elevations of NT‐proBNP, hsTnT, GDF‐15, sST2 were associated with incident HF. There was a borderline association of galectin‐3 with incident HF. NT‐proBNP and hsTnT were more strongly associated with HF with reduced EF, while the associations of the newer biomarkers GDF‐15 and sST2 were stronger for HF with preserved EF.