A Personalized Approach to Chronic Kidney Disease and Cardiovascular Disease: JACC Review Topic of the Week

Exercise training and chronic kidney disease: characterization and bibliometrics of citation classics of clinical intervention trials

BACKGROUND

Exercise research targeting chronic kidney disease (CKD) has been conducted for more than 30 years, and the benefits of exercise for CKD patients have been progressively demonstrated. This study analyzes citation classics on clinical intervention trials on exercise training and CKD to describe the research landscape and hotspots through bibliometric analysis.

METHODS

To identify clinical trials of exercise training interventions for CKD with more than 100 citations from the Web of Science Core Collection database. Extracted bibliometric information, participant information, and study characteristics of the included articles. The total citations, annual average citations, publication of year, author keywords, and study-related data were bibliometric analyzed and described using Excel 2019 and VOSviewer software.

RESULTS

A total of 30 citation classics were included, with a total citation frequency of 102 to 279 (mean ± standard deviation: 148.4 ± 49.4). The American Journal of Kidney Diseases (n = 7) published the most (n = 7) classic citations in the field of CKD exercise research, and the Journal of the American Society of Nephrology was the most cited. The hotspot of research around CKD and exercise training interventions focused on population (hemodialysis and end-stage renal disease), exercise type (resistance training, yoga, and leg-cycling), and outcomes (cardiovascular indices, physical performance, psychological status, kidney function, physical activity). Reported dropout rates ranged from 0.0% to 47.4%.

CONCLUSION

A bibliometric analysis of citation classics on exercise training and CKD highlights the potential benefits of exercise as a non-pharmacological therapy for patients with CKD, as well as developments and hotspots in the field.

Increased indexed proximal aortic diameter is a predictor of poor prognosis in maintenance hemodialysis patients

Background: Recent studies have shown that the baseline values of absolute aortic root diameter (ARD) and indexed diameter are associated with all-cause mortality and cardiovascular events in the general population, even in the absence of aneurysmal aortic disease. However, there is limited available data on the association between ARD and prognosis in end-stage renal disease (ESRD) patients receiving maintenance hemodialysis (MHD). Accordingly, the purpose of this study is to investigate the predictive value of ARD for all-cause mortality and cardiovascular events in this specific population.Methods: ARD was measured by echocardiography at the level of the sinuses of Valsalva at end diastole and indexed to body surface area (BSA). The primary endpoint was all-cause mortality. The secondary endpoint was major adverse cardiovascular events (MACE), including cardiovascular mortality, myocardial infarction and stroke. Cox proportional hazards models were conducted to evaluate the association between baseline ARD/BSA and clinical outcomes.Results: A total of 391 patients were included in this study. The primary endpoint occurred in 95 (24.3%) patients while the secondary endpoint occurred in 71 (18.2%) patients. Multivariate Cox regression analysis showed that ARD/BSA was an independent prognostic factor for all-cause mortality (HR, per 1-SD increase, 1.403; 95% CI, 1.118-1.761; p = 0.003) as well as MACE (HR, per 1-SD increase, 1.356; 95% CI, 1.037-1.772; p = 0.026).Conclusions: Our results show that ARD/BSA is predictive of all-cause mortality and MACE in MHD patients with ESRD and support the view that assessment of ARD/BSA may refine risk stratification and preventive strategies in this population.

Renin-angiotensin system inhibition and mortality in patients undergoing dialysis with coronary artery disease: insights from a multi-center observational study

BACKGROUND

While the survival benefits of angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) are firmly established in the general population, their efficacy within patient undergoing dialysis with coronary artery disease (CAD) remains controversial.

METHODS

Between January 2015 and June 2021, 1168 patients undergoing dialysis with CAD were assessed from 30 tertiary medical centers. The primary outcome was all-cause death, and the secondary outcome was cardiovascular death. Inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) were performed to account for between-group differences.

RESULTS

Overall, ACEI or ARB were prescribed to 518 patients (44.3%) upon discharge. After a median follow-up of 22.2 months, 361 (30.9%) patients died, including 243 cardiovascular deaths. The use of ACEI or ARB was associated with a significantly lower risk of all-cause (25.3% vs 35.4%, hazard ratio [HR] 0.65, 95% confidence interval [CI] 0.52-0.82, p < 0.001) and cardiovascular death (17.0% vs 23.8%; HR 0.64, 95% CI 0.48-0.83, p = 0.001). These findings remained consistent across IPTW and PSM analyses. Sensitivity analyses for ACEI and ARB use separately yielded similar results.

CONCLUSIONS

Our findings suggested that among patients undergoing dialysis with CAD, ACEI or ARB use was associated with a lower risk of all-cause and cardiovascular death.

High Fibrinogen Levels with Diabetes Mellitus are Associated with All-Cause and Cardiovascular Mortality in Patients with End-Stage Renal Disease and Acute Coronary Syndrome

Objective

As a biomarker of inflammation and a core component in the coagulation pathway, fibrinogen contributes to atherosclerosis and subsequent adverse cardiovascular events and is modified by the occurrence of diabetes mellitus. However, the association between fibrinogen, diabetes status, and mortality in patients with end-stage renal disease (ESRD) and acute coronary syndrome (ACS) remains scarce.

Methods

A multi-center cohort study enrolled 1079 patients with ESRD and ACS between January 2015 and June 2021. Patients were classified into three groups based on fibrinogen tertiles and were further categorized by diabetes status. The primary outcome was all-cause mortality, while the secondary outcome was cardiovascular mortality.

Results

During a median 21.5 months of follow-up, 386 cases of all-cause mortality were recorded, including 262 cases of cardiovascular mortality. Multivariable Cox regression model revealed that patients with the third tertile of fibrinogen and those with diabetes experienced a significantly increased risk of all-cause mortality (fibrinogen: hazard ratio [HR], 1.70; 95% confidence interval [CI], 1.32-2.19; diabetes: HR, 1.36; 95% CI, 1.10-1.68). When patients were stratified by both fibrinogen levels and diabetes status, patients in the third fibrinogen tertile with diabetes had the highest risk of all-cause mortality (HR 2.43, 95% CI 1.69-3.48) compared to those in the first fibrinogen tertile without diabetes. Similar associations were observed for cardiovascular mortality. Notably, incorporating the combined fibrinogen and diabetes status into the Global Registry of Acute Coronary Events (GRACE) score or baseline risk model led to significant improvements in the C-statistics for predicting mortality, surpassing the advancements achieved with any single biomarker.

Conclusion

In patients with ESRD and ACS, elevated fibrinogen and diabetes were associated with an increased risk of all-cause and cardiovascular mortality. Categorizing patients based on fibrinogen levels and diabetes status could provide valuable information for risk stratification of these patients.

Percutaneous coronary intervention vs . medical therapy in patients on dialysis with coronary artery disease in China

BACKGROUND

The available evidence regarding the benefits of percutaneous coronary intervention (PCI) on patients receiving dialysis with coronary artery disease (CAD) is limited and inconsistent. This study aimed to evaluate the association between PCI and clinical outcomes as compared with medical therapy alone in patients undergoing dialysis with CAD in China.

METHODS

This multicenter, retrospective study was conducted in 30 tertiary medical centers across 12 provinces in China from January 2015 to June 2021 to include patients on dialysis with CAD. The primary outcome was major adverse cardiovascular events (MACE), defined as a composite of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke. Secondary outcomes included all-cause death, the individual components of MACE, and Bleeding Academic Research Consortium criteria types 2, 3, or 5 bleeding. Multivariable Cox proportional hazard models were used to assess the association between PCI and outcomes. Inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) were performed to account for potential between-group differences.

RESULTS

Of the 1146 patients on dialysis with significant CAD, 821 (71.6%) underwent PCI. After a median follow-up of 23.0 months, PCI was associated with a 43.0% significantly lower risk for MACE (33.9% [ n  = 278] vs . 43.7% [ n  = 142]; adjusted hazards ratio 0.57, 95% confidence interval 0.45-0.71), along with a slightly increased risk for bleeding outcomes that did not reach statistical significance (11.1% vs . 8.3%; adjusted hazards ratio 1.31, 95% confidence interval, 0.82-2.11). Furthermore, PCI was associated with a significant reduction in all-cause and cardiovascular mortalities. Subgroup analysis did not modify the association of PCI with patient outcomes. These primary findings were consistent across IPTW, PSM, and competing risk analyses.

CONCLUSION

This study indicated that PCI in patients on dialysis with CAD was significantly associated with lower MACE and mortality when comparing with those with medical therapy alone, albeit with a slightly increased risk for bleeding events that did not reach statistical significance.

Prognostic significance of the hs-CRP/Alb ratio for cardiovascular events in patients with end-stage renal disease undergoing maintenance hemodialysis

OBJECTIVE

To evaluate the predictive power of the high-sensitivity C-reactive protein (hs-CRP) to albumin (Alb) ratio for cardiovascular events in patients receiving maintenance hemodialysis (MHD) for end-stage renal disease (ESRD).

METHODS

This retrospective study enrolled 202 ESRD patients undergoing MHD at Bobai County People's Hospital from November 2020 to November 2022, with follow-up extending to November 2023. Patients were divided into two groups based on the occurrence of cardiovascular events during follow-up: the occurrence group (n = 92) and the non-occurrence group (n = 110). Clinical data were compared between these groups. Independent risk factors for cardiovascular events post-MHD were identified using a multivariate logistic regression model. The hs-CRP/Alb ratio's predictive utility was assessed through receiver operating characteristic (ROC) curve analysis, establishing an optimal cutoff value. A decision tree prediction model was developed to further delineate the probability of cardiovascular events.

RESULTS

The occurrence group was older and had a longer duration of dialysis compared to the non-occurrence group (P < 0.05). They also showed a higher prevalence of diabetic and hypertensive nephropathy and a higher proportion of smokers (all P < 0.05). Notably lower levels of hemoglobin (HGB), triglycerides, total cholesterol, low-density lipoprotein, albumin (Alb), and calcium were detected (all P < 0.05), whereas β2-microglobulin (β2-mg), hs-CRP, phosphorus, and the hs-CRP/Alb ratio were markedly increased (all P < 0.05). Multivariate analysis revealed diabetic nephropathy or hypertensive nephropathy, a high hs-CRP/Alb ratio, and elevated phosphorus levels as risk factors for cardiovascular events, while high hemoglobin levels were protective (P < 0.05). The ROC analysis indicated the hs-CRP/Alb ratio (AUC = 0.884) outperformed other predictors with an optimal cutoff at 0.111. Patients with a hs-CRP/Alb ratio ≥ 0.111 were found to have a 29-fold increased risk of cardiovascular events (95% CI: 11.304-74.842).

CONCLUSION

The hs-CRP/Alb ratio is a significant predictive biomarker for cardiovascular events in ESRD patients undergoing MHD. An elevated hs-CRP/Alb ratio is associated with an increased risk of cardiovascular events, underscoring its utility in this patient population.

Impact of resistance exercise on patients with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) has become an increasingly important public health disease with a high incidence rate and mortality. Although several studies have explored the effectiveness of resistance exercise in improving the prognosis of CKD patients, the number of studies is still limited and the results are still controversial.

OBJECTIVES

We conducted this meta-analysis of randomized controlled trials (RCT) studies to evaluate the effectiveness of resistance exercise on CKD patients.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched from the inception date to October 2023. The meta-analysis was conducted to evaluate 12 main indicators, including glomerular filtration rate (GFR)(ml/(min•1.73m2)), C-reactive protein (CRP) (mg/L), serum creatinine (mg/dL), hemoglobin (g/dL), Glycosylated Hemoglobin, Type A1C (HBA1c) (%), high Density Lipoprotein (HDL) (mg/dL), low Density Lipoprotein (LDL) (mg/dL), 6-min walk(m), body mass index (BMI) (kg/m2), fat-free mass (kg), fat mass (kg), grip strength (kgf).

RESULTS

Sixteen RCT studies were included in this meta-analysis from 875 records. GFR exhibited no significant change in CKD patients treated with resistance exercise (WMD 1.82; 95%CI -0.59 to 4.23; P = 0.139). However, 6-min walk (WMD 89.93; 95%CI 50.12 to 129.74; P = 0.000), fat-free mass (WMD 6.53; 95%CI 1.14 to 11.93; P = 0.018) and grip strength (WMD 3.97; 95%CI 1.89 to 6.05; P = 0.000) were significantly improved with resistance exercise. The level of CRP (WMD - 2.46; 95%CI -4.21 to -0.72; P = 0.006) and HBA1c (WMD - 0.46; 95%CI -0.63 to -0.29; P = 0.000) dropped significantly after resistance exercise treatment.

CONCLUSIONS

Resistance exercise can improve physical function, metabolic condition, inflammatory response and cardiopulmonary function in CKD patients, specifically reflected in the increase of indicators fat-free mass, grip strength, 6-min walk, as well as the decrease of indicators HBA1c and CRP.

Risk prediction models for cardiovascular events in hemodialysis patients: A systematic review

OBJECTIVE

To perform a systematic review of risk prediction models for cardiovascular (CV) events in hemodialysis (HD) patients, and provide a reference for the application and optimization of related prediction models.

METHODS

PubMed, The Cochrane Library, Web of Science, and Embase databases were searched from inception to 1 February 2023. Two authors independently conducted the literature search, selection, and screening. The Prediction model Risk Of Bias Assessment Tool (PROBAST) was applied to evaluate the risk of bias and applicability of the included literature.

RESULTS

A total of nine studies containing 12 models were included, with performance measured by the area under the receiver operating characteristic curve (AUC) lying between 0.70 and 0.88. Age, diabetes mellitus (DM), C-reactive protein (CRP), and albumin (ALB) were the most commonly identified predictors of CV events in HD patients. While the included models demonstrated good applicability, there were still certain risks of bias, primarily related to inadequate handling of missing data and transformation of continuous variables, as well as a lack of model performance validation.

CONCLUSION

The included models showed good overall predictive performance and can assist healthcare professionals in the early identification of high-risk individuals for CV events in HD patients. In the future, the modeling methods should be improved, or the existing models should undergo external validation to provide better guidance for clinical practice.

The moderating effect of fluid overload on the relationship between the augmentation index and left ventricular diastolic function in patients with CKD

Increased vascular stiffness, fluid overload, and left ventricular diastolic dysfunction (LVDD) are common in patients with chronic kidney disease (CKD). We investigated the potential moderating effect of volume status in the relationship between arterial stiffness and left ventricular (LV) diastolic function in non-dialysis patients with stage 5 CKD. The radial augmentation index at a heart rate of 75 beats/min (rAIx75), overhydration/extracellular water (OH/ECW), and E/e´ ratio were concurrently measured in 152 consecutive patients. Each of these parameters reflects the status of vascular stiffness, fluid balance, and LV diastolic function, respectively. Hierarchical regression analysis demonstrated a significant interaction effect of OH/ECW for all patients (P = 0.015), even after controlling for confounders. In separate analyses, this interaction effect was particularly significant in women (P = 0.010), whereas its significance in patients with diabetes was marginally significant (P = 0.062). Our study suggested that fluid overload could be one of the more aggravating factors of LVDD in patients with CKD who have increased arterial stiffness. Therefore, it is advisable to conduct simultaneous assessments of vascular stiffness, fluid balance, and LV function, particularly in the specific groups mentioned earlier. Our results may serve as evidence applicable to patients with chronic heart failure.

Association between the Suita Score and Body Composition in Japanese Adults: A Large Cross-Sectional Study

The purpose of this study was to clarify the relationship between the Suita score (a prediction model for the development of cardiovascular disease) and body composition in Japanese health check-up subjects (6873 men and 8685 women). The Suita score includes 8 items (age, gender, smoking, diabetes, blood pressure, low-density lipoprotein, high-density lipoprotein, and chronic kidney disease). Factors associated with the Suita score within body composition-related parameters (body mass index (BMI), waist circumference (WC), fat mass index, fat-free mass index, fat mass to fat-free mass ratio (F-FF ratio), and water mass index) as assessed by bioelectrical impedance analysis were examined. The mean age of subjects was 54.8 years in men and 52.8 years in women (p < 0.0001). The mean BMI was 23.9 kg/m2 in men and 21.8 kg/m2 in women (p < 0.0001). Diabetes mellitus was found in 1282 subjects (18.7%) among men and 816 subjects (9.4%) among women (p < 0.0001). The mean Suita score was 42.0 in men and 29.6 in women (p < 0.0001). In multivariate analysis, WC (p < 0.0001), F-FF ratio (p < 0.0001), and water mass index (p < 0.0001) were independent factors linked to the Suita score for both genders. In conclusion, body composition can be associated with the Suita score in Japanese adults receiving health check-ups.

Predictive value of the stress hyperglycemia ratio in dialysis patients with acute coronary syndrome: insights from a multi-center observational study

BACKGROUND

Various studies have indicated that stress hyperglycemia ratio (SHR) can reflect true acute hyperglycemic status and is associated with poor outcomes in patients with acute coronary syndrome (ACS). However, data on dialysis patients with ACS are limited. The Global Registry of Acute Coronary Events (GRACE) risk score is a well-validated risk prediction tool for ACS patients, yet it underestimates the risk of major events in patients receiving dialysis. This study aimed to evaluate the association between SHR and adverse cardiovascular events in dialysis patients with ACS and explore the potential incremental prognostic value of incorporating SHR into the GRACE risk score.

METHODS

This study enrolled 714 dialysis patients with ACS from January 2015 to June 2021 at 30 tertiary medical centers in China. Patients were stratified into three groups based on the tertiles of SHR. The primary outcome was major adverse cardiovascular events (MACE), and the secondary outcomes were all-cause mortality and cardiovascular mortality.

RESULTS

After a median follow-up of 20.9 months, 345 (48.3%) MACE and 280 (39.2%) all-cause mortality occurred, comprising 205 cases of cardiovascular death. When the highest SHR tertile was compared to the second SHR tertile, a significantly increased risk of MACE (adjusted hazard ratio, 1.92; 95% CI, 1.48-2.49), all-cause mortality (adjusted hazard ratio, 2.19; 95% CI, 1.64-2.93), and cardiovascular mortality (adjusted hazard ratio, 2.70; 95% CI, 1.90-3.83) was identified in the multivariable Cox regression model. A similar association was observed in both diabetic and nondiabetic patients. Further restricted cubic spline analysis identified a J-shaped association between the SHR and primary and secondary outcomes, with hazard ratios for MACE and mortality significantly increasing when SHR was > 1.08. Furthermore, adding SHR to the GRACE score led to a significant improvement in its predictive accuracy for MACE and mortality, as measured by the C-statistic, net reclassification improvement, and integrated discrimination improvement, especially for those with diabetes.

CONCLUSIONS

In dialysis patients with ACS, SHR was independently associated with increased risks of MACE and mortality. Furthermore, SHR may aid in improving the predictive efficiency of the GRACE score, especially for those with diabetes. These results indicated that SHR might be a valuable tool for risk stratification and management of dialysis patients with ACS.

The triglyceride-glucose index predicts 1-year major adverse cardiovascular events in end-stage renal disease patients with coronary artery disease

BACKGROUND

The triglyceride-glucose (TyG) index has been suggested as a dependable indicator for predicting major adverse cardiovascular events (MACE) in individuals with cardiovascular conditions. Nevertheless, there is insufficient data on the predictive significance of the TyG index in end-stage renal disease (ESRD) patients with coronary artery disease (CAD).

METHODS

This study, conducted at multiple centers in China, included 959 patients diagnosed with dialysis and CAD from January 2015 to June 2021. Based on the TyG index, the participants were categorized into three distinct groups. The study's primary endpoint was the combination of MACE occurring within one year of follow-up, including death from any cause, non-fatal myocardial infarction, and non-fatal stroke. We assessed the association between the TyG index and MACE using Cox proportional hazard models and restricted cubic spline analysis. The TyG index value was evaluated for prediction incrementally using C-statistics, continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

RESULTS

The three groups showed notable variations in the risk of MACE (16.3% in tertile 1, 23.5% in tertile 2, and 27.2% in tertile 3; log-rank P = 0.003). Following complete adjustment, patients with the highest TyG index exhibited a notably elevated risk of MACE in comparison to those in the lowest tertile (hazard ratio [HR] 1.63, 95% confidence interval [CI] 1.14-2.35, P = 0.007). Likewise, each unit increase in the TyG index correlated with a 1.37-fold higher risk of MACE (HR 1.37, 95% CI 1.13-1.66, P = 0.001). Restricted cubic spline analysis revealed a connection between the TyG index and MACE (P for nonlinearity > 0.05). Furthermore, incorporating the TyG index to the Global Registry of Acute Coronary Events risk score or baseline risk model with fully adjusted factors considerably enhanced the forecast of MACE, as demonstrated by the C-statistic, continuous NRI, and IDI.

CONCLUSIONS

The TyG index might serve as a valuable and dependable indicator of MACE risk in individuals with dialysis and CAD, indicating its potential significance in enhancing risk categorization in clinical settings.

Association of triglyceride-glucose index with coronary severity and mortality in patients on dialysis with coronary artery disease

BACKGROUND

The triglyceride-glucose (TyG) index is validated as a reliable biomarker of insulin resistance and an independent predictor of cardiovascular prognosis. However, the prognostic value of the TyG index in patients on dialysis with coronary artery disease (CAD) remained unexplored. This study aimed to determine the association between the TyG index and CAD severity and mortality in these patients.

METHODS

A total of 1061 dialysis patients with CAD were enrolled in this multi-center cohort study from January 2015 to June 2021. The extent and severity of CAD were evaluated using the multivessel disease and Gensini score (GS). Patients were followed up for all-cause death and cardiovascular death.

RESULTS

The multivariable logistic regression model indicated that the TyG index was significantly associated with multivessel disease (odds ratio [OR] 1.51, 95% confidence interval [CI] 1.18-1.94, P = 0.001), and high GS (OR 1.33, 95% CI 1.10-1.61, P = 0.003). After adjusting for baseline risk factors, the hazards of all-cause death and cardiovascular death were 1.23 (95% CI 1.06-1.43, P = 0.007), and 1.33 (95% CI 1.11-1.59, P = 0.002), independent of CAD severity. Restricted cubic spline analysis identified a dose-response association between the TyG index and both CAD severity and mortality (all P for nonlinearity > 0.05). When modeling the TyG index as a categorical variable, these independent associations remained. Subgroup analyses did not substantially modify the results. Furthermore, incorporating the TyG index into the existing risk prediction model improved the predictive accuracy for all-cause death and cardiovascular death, as evaluated by C-statistic, continuous net reclassification improvement, and integrated discrimination improvement.

CONCLUSIONS

In patients on dialysis with CAD, the TyG index was significantly associated with more severe CAD as well as mortality. These results highlight the clinical importance of the TyG index for assessing CAD severity and risk stratification in patients on dialysis with CAD.

Antiplatelet Therapy in End-stage Renal Disease Patients on Maintenance Dialysis: a State-of-the-art Review

Patients with end-stage renal disease (ESRD) on maintenance dialysis have an increased risk of ischaemic events, such as recurrent myocardial infarction (MI) and stroke. Potent antiplatelet therapy may help mitigate this risk. Nonetheless, ERSD patients are also at increased risk of bleeding due to their complex vascular milieu, which limits the routine use of potent P2Y12 inhibitors. Moreover, these patients are often underrepresented or excluded from major clinical trials leaving a significant gap in existing knowledge. Understanding the mechanisms of this paradox may serve as a benchmark for the development of ESRD trials. The present review aims to provide an overview of the pathophysiological nature of increased bleeding and ischaemic risks in ERSD patients as well as summarize available evidence of antiplatelet use and propose new concepts to guide physicians in selecting appropriate drug regimes for this high-risk cohort.

Development and validation of a multivariate model for predicting heart failure hospitalization and mortality in patients receiving maintenance hemodialysis

BACKGROUND

Heart failure (HF) in patients undergoing maintenance hemodialysis (MHD) increases their hospitalization rates, mortality, and economic burden significantly. We aimed to develop and validate a predictive model utilizing contemporary deep phenotyping for individual risk assessment of all-cause mortality or HF hospitalization in patients on MHD.

MATERIALS AND METHODS

A retrospective review was conducted from January 2017 to October 2022, including 348 patients receiving MHD from four centers. The variables were adjusted by Cox regression analysis, and the clinical prediction model was constructed and verified.

RESULTS

The median follow-up durations were 14 months (interquartile range [IQR] 9-21) for the modeling set and 14 months (9-20) for the validation set. The composite outcome occurred in 72 (29.63%) of 243 patients in the modeling set and 39 (37.14%) of 105 patients in the validation set. The model predictors included age, albumin, history of cerebral hemorrhage, use of angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers/"sacubitril/valsartan", left ventricular ejection fraction, urea reduction ratio, N-terminal prohormone of brain natriuretic peptide, and right atrial size. The C-index was 0.834 (95% CI 0.784-0.883) for the modeling set and 0.853 (0.798, 0.908) for the validation set. The model exhibited excellent calibration across the complete risk profile, and the decision curve analysis (DCA) suggested its ability to maximize patient benefits.

CONCLUSION

The developed prediction model offered an accurate and personalized assessment of HF hospitalization risk and all-cause mortality in patients with MHD. It can be employed to identify high-risk patients and guide treatment and follow-up.

Comparing Left Ventricular Diastolic Function between Peritoneal Dialysis and Non-Dialysis Patients with Stage 5 Chronic Kidney Disease: A Propensity Score-Matched Analysis

Patients with chronic kidney disease (CKD) have a high incidence of left ventricular diastolic dysfunction (LVDD), which increases the risk of heart failure and mortality. We assessed fluid overload as an independent risk factor for LVDD in patients with decreased kidney function and compared its impact on the E/e' ratio as a parameter for assessing left ventricular diastolic functions between patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and those with non-dialysis CKD stage 5 (CKD5) using propensity score matching (PSM). After PSM, 222 patients (CAPD, n = 111; CKD5, n = 111) were included. Fluid balance was assessed using bio-impedance spectroscopy and LVDD was determined by echocardiography based on an E/e' ratio of >15. The CKD5 group had a significantly higher E/e' ratio (p = 0.002), while fluid overload (OH/ECW) did not differ significantly between the groups. In the CAPD group, there were no significant differences in OH/ECW between patients with and without LVDD (p = 0.517). However, in the CKD5 group, patients with LVDD showed a significantly higher OH/ECW (p = 0.001). In a regression analysis investigating factors associated with the E/e' ratio, OH/ECW was not significantly associated with the E/e' ratio in the CAPD group (p = 0.087), but in the CKD5 group, it was independently correlated (p = 0.047). The factors closely associated with LVDD varied depending on dialysis dependence. While fluid overload independently influenced LVDD in non-dialysis patients, it was not statistically significant in patients with CAPD. Early assessment and management of volume status are crucial in addressing LVDD in patients with advanced-stage CKD.

Cardiac Phase and Flow Compensation Effects on REnal Flow and Microstructure AnisotroPy MRI in Healthy Human Kidney

BACKGROUND

Renal diffusion-weighted imaging (DWI) involves microstructure and microcirculation, quantified with diffusion tensor imaging (DTI), intravoxel incoherent motion (IVIM), and hybrid models. A better understanding of their contrast may increase specificity.

PURPOSE

To measure modulation of DWI with cardiac phase and flow-compensated (FC) diffusion gradient waveforms.

STUDY TYPE

Prospective.

POPULATION

Six healthy volunteers (ages: 22-48 years, five females), water phantom.

FIELD STRENGTH/SEQUENCE

3-T, prototype DWI sequence with 2D echo-planar imaging, and bipolar (BP) or FC gradients. 2D Half-Fourier Single-shot Turbo-spin-Echo (HASTE). Multiple-phase 2D spoiled gradient-echo phase contrast (PC) MRI.

ASSESSMENT

BP and FC water signal decays were qualitatively compared. Renal arteries and velocities were visualized on PC-MRI. Systolic (peak velocity), diastolic (end stable velocity), and pre-systolic (before peak velocity) phases were identified. Following mutual information-based retrospective self-registration of DWI within each kidney, and Marchenko-Pastur Principal Component Analysis (MPPCA) denoising, combined IVIM-DTI analysis estimated mean diffusivity (MD), fractional anisotropy (FA), and eigenvalues (λi) from tissue diffusivity (Dt ), perfusion fraction (fp ), and pseudodiffusivity (Dp , Dp,axial , Dp,radial ), for each tissue (cortex/medulla, segmented on b0/FA respectively), phase, and waveform (BP, FC). Monte Carlo water diffusion simulations aided data interpretation.

STATISTICAL TESTS

Mixed model regression probed differences between tissue types and pulse sequences. Univariate general linear model analysis probed variations among cardiac phases. Spearman correlations were measured between diffusion metrics and renal artery velocities. Statistical significance level was set at P < 0.05.

RESULTS

Water BP and FC signal decays showed no differences. Significant pulse sequence dependence occurred for λ1 , λ3 , FA, Dp , fp , Dp,axial , Dp,radial in cortex and medulla, and medullary λ2 . Significant cortex/medulla differences occurred with BP for all metrics except MD (systole [P = 0.224]; diastole [P = 0.556]). Significant phase dependence occurred for Dp , Dp,axial , Dp,radial for BP and medullary λ1 , λ2 , λ3 , MD for FC. FA correlated significantly with velocity. Monte Carlo simulations indicated medullary measurements were consistent with a 34 μm tubule diameter.

DATA CONCLUSION

Cardiac gating and flow compensation modulate of measurements of renal diffusion.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY STAGE: 2.

Coronary microcirculation and left ventricular diastolic function but not myocardial deformation indices are impaired early in patients with chronic kidney disease

AIM

To investigate abnormalities in myocardial strain and classic echocardiographic indices and coronary flow reserve (CFR), in younger versus older CKD patients.

METHODS

Sixty consecutive CKD patients (<60 years old n = 30, ≥60 years old n = 30) and 30 healthy controls (age- and gender-matched with younger CKD patients) were recruited. An echocardiographic assessment including myocardial strain indices (i.e. global longitudinal strain -GLS -, TWIST, UNTWIST rate) was performed at baseline and following dipyridamole administration in all participants.

RESULTS

Younger CKD patients had higher E/e', left ventricular mass index and relative wall thickness and lower E' (p < .005 for all) compared to healthy controls. Older CKD patients had lower E/A and E' (p < .05 for both) compared to younger CKD patients; these differences did not remain significant after adjustment for age. CFR was higher in healthy controls compared to younger and older CKD patients (p < .05 for both) without a significant difference between CKD groups. There were no significant differences in GLS, TWIST or UNTWIST values among the three groups of patients. Dipyridamole-induced changes did not differ significantly among the three groups.

CONCLUSIONS

Compared to healthy controls, impaired coronary microcirculation and left ventricular diastolic function, but not myocardial strain abnormalities, are found in young CKD patients and deteriorate with aging.

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.

Dysbiosis of Gut Microbiota Contributes to Uremic Cardiomyopathy via Induction of IFNγ-Producing CD4+ T Cells Expansion

Uremic cardiomyopathy (UCM) correlates with chronic kidney disease (CKD)-induced morbidity and mortality. Gut microbiota has been involved in the pathogenesis of certain cardiovascular disease, but the role of gut microbiota in the pathogenesis of UCM remains unknown. Here, we performed a case-control study to compare the gut microbiota of patients with CKD and healthy controls by 16S rRNA (rRNA) gene sequencing. To test the causative relationship between gut microbiota and UCM, we performed fecal microbiota transplantation (FMT) in 5/6th nephrectomy model of CKD. We found that opportunistic pathogens, particularly Klebsiella pneumoniae (K. pneumoniae), are markedly enriched in patients with CKD. FMT from CKD patients aggravated diastolic dysfunction in the mouse model. The diastolic dysfunction was associated with microbiome-dependent increases in heart-infiltrating IFNγ+ CD4+ T cells. Monocolonization with K. pneumoniae increased cardiac IFNγ+ CD4+ T cells infiltration and promoted UCM development of the mouse model. A probiotic Bifidobacterium animalis decreased the relative abundance of K. pneumoniae, reduced levels of cardiac IFNγ+ CD4+ T cells and ameliorated the severity of diastolic dysfunction in the mice. Thus, the aberrant gut microbiota in CKD patients, especially K. pneumoniae, contributed to UCM pathogenesis through the induction of heart-infiltrating IFNγ+ CD4+ T cells expansion, proposing that a Gut Microbiota-Gut-Kidney-Heart axis could play a critical role in elucidating the etiology of UCM, and suggesting that modulation of the gut bacteria may serve as a promising target for the amelioration of UCM. IMPORTANCE Uremic cardiomyopathy (UCM) correlates tightly with increased mortality in patients with chronic kidney disease (CKD), yet the pathogenesis of UCM remains incompletely understood, limiting therapeutic approaches. Our study proposed that a Gut Microbiota-Gut-Kidney-Heart axis could play a critical role in understanding etiology of UCM. There is a major need in future clinical trials of patients with CKD to explore if modulation of gut microbiota by fecal microbiota transplantation (FMT), probiotics or antibiotics can alleviate cardiac dysfunction, reduce mortality, and improve life quality.

One-Year Mortality after Hemodialysis Initiation: The Prognostic Role of the CHA2DS2-VASc Score

BACKGROUND

CKD is a significant cause of morbidity, cardiovascular and all-cause mortality. CHA2DS2-VASc is a score used in patients with atrial fibrillation to predict thromboembolic risk; it also appears to be useful to predict mortality risk. The aim of the study was to evaluate CHA2DS2-VASc scores as a tool for predicting one-year mortality after hemodialysis is started and for identifying factors associated with higher mortality.

METHODS

Retrospective analysis of patients who started hemodialysis between January 2014 and December 2019 in Centro Hospitalar Universitário Lisboa Norte. We evaluated mortality within one year of hemodialysis initiation. The CHA2DS2-VASc score was calculated at the start of hemodialysis.

RESULTS

Of 856 patients analyzed, their mean age was 68.3 ± 15.5 years and the majority were male (61.1%) and Caucasian (84.5%). Mortality within one-year after starting hemodialysis was 17.8% (n = 152). The CHA2DS2-VASc score was significantly higher (4.4 ± 1.7 vs. 3.5 ± 1.8, p < 0.001) in patients who died and satisfactorily predicted the one-year risk of mortality (AUC 0.646, 95% CI 0.6-0.7, p < 0.001), with a sensitivity of 71.7%, a specificity of 49.1%, a positive predictive value of 23.9% and a negative predictive value of 89.2%. In the multivariate analysis, CHA2DS2-VASc ≥3.5 (adjusted HR 2.24 95% CI (1.48-3.37), p < 0.001) and central venous catheter at dialysis initiation (adjusted HR 3.06 95% CI (1.93-4.85)) were significant predictors of one-year mortality.

CONCLUSION

A CHA2DS2-VASc score ≥3.5 and central venous catheter at hemodialysis initiation were predictors of one-year mortality, allowing for risk stratification in hemodialysis patients.

The prediction of in-hospital mortality in chronic kidney disease patients with coronary artery disease using machine learning models

OBJECTIVE

Chronic kidney disease (CKD) patients with coronary artery disease (CAD) in the intensive care unit (ICU) have higher in-hospital mortality and poorer prognosis than patients with either single condition. The objective of this study is to develop a novel model that can predict the in-hospital mortality of that kind of patient in the ICU using machine learning methods.

METHODS

Data of CKD patients with CAD were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Boruta algorithm was conducted for the feature selection process. Eight machine learning algorithms, such as logistic regression (LR), random forest (RF), Decision Tree, K-nearest neighbors (KNN), Gradient Boosting Decision Tree Machine (GBDT), Support Vector Machine (SVM), Neural Network (NN), and Extreme Gradient Boosting (XGBoost), were conducted to construct the predictive model for in-hospital mortality and performance was evaluated by average precision (AP) and area under the receiver operating characteristic curve (AUC). Shapley Additive Explanations (SHAP) algorithm was applied to explain the model visually. Moreover, data from the Telehealth Intensive Care Unit Collaborative Research Database (eICU-CRD) were acquired as an external validation set.

RESULTS

3590 and 1657 CKD patients with CAD were acquired from MIMIC-IV and eICU-CRD databases, respectively. A total of 78 variables were selected for the machine learning model development process. Comparatively, GBDT had the highest predictive performance according to the results of AUC (0.946) and AP (0.778). The SHAP method reveals the top 20 factors based on the importance ranking. In addition, GBDT had good predictive value and a certain degree of clinical value in the external validation according to the AUC (0.865), AP (0.672), decision curve analysis, and calibration curve.

CONCLUSION

Machine learning algorithms, especially GBDT, can be reliable tools for accurately predicting the in-hospital mortality risk for CKD patients with CAD in the ICU. This contributed to providing optimal resource allocation and reducing in-hospital mortality by tailoring precise management and implementation of early interventions.

Prognostic Effects of Changes in Right Ventricular Fractional Area Change in Patients With Heart Failure

BACKGROUND

It is still unclear whether changes in right ventricular function are associated with prognosis in heart failure (HF) patients. This study aimed to examine the prognostic effect of changes in right ventricular fractional area change (RVFAC).

METHODS AND RESULTS

This study enrolled 480 hospitalized patients with decompensated HF, and measured RVFAC with echocardiography at discharge (first examination) and post-discharge in the outpatient setting (second examination). RVFAC was divided into 3 categories: >35% in 314 patients, 25-35% in 108 patients, and <25% in 58 patients. Next, based on changes in RVFAC from the first to the second examination, the patients were further classed into 4 groups: (1) Preserved/Unchanged (preserved and unchanged RVFAC, n=235); (2) Reduced/Improved (improved RVFAC in at least 1 category, n=106); (3) Reduced/Unchanged (reduced and unchanged RVFAC, n=47); and (4) Preserved or Reduced/Worsened (deteriorated RVAFC in at least 1 category, n=92). Multivariate logistic regression analysis revealed that chronic kidney disease and anemia were the predictors of the preserved or reduced/worsened RVFAC. In the Kaplan-Meier analysis, changes in RVFAC were associated with the cardiac event rate and all-cause mortality. In the multivariable Cox proportional hazard analysis, the preserved or reduced/worsened RVFAC was an independent predictor of cardiac events and all-cause mortality.

CONCLUSIONS

Changes in RVFAC were associated with post-discharge prognosis in hospitalized heart failure patients.

Association between triglyceride-glucose index and worsening renal function in the elderly

Background

Triglyceride-glucose (TyG) index is a simple marker of insulin resistance. However, insufficient data is available on whether the TyG index is associated with worsening renal function (WRF) in the elderly. Therefore, this study was designed to explore the association between the TyG index and WRF based on a community elderly cohort.

Methods

In this study, 7,822 elderly (aged ≥ 65 years) adults from southern China were enrolled and divided into four groups according to the TyG index quartiles. The primary endpoint was incident chronic kidney disease (CKD), defined as incident estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m². Additional endpoints included a decline in eGFR of 30% and 40% during the follow-up period.

Results

During the median 2.04 year follow-up period, 1,541 (19.7%) participants developed CKD. After adjusting for confounding factors, multivariable Cox regression models revealed significant associations between TyG index and incident CKD (HR per SD increase, 1.21; 95% CI: 1.14-1.29), a decline in eGFR of 30% (HR per SD increase, 1.38; 95% CI: 1.26-1.50), and decline in eGFR of 40% (HR per SD increase, 1.42; 95% CI: 1.24-1.63). Furthermore, compared with those in Q1, participants in Q4 demonstrated a higher risk of developing CKD (HR, 1.59; 95% CI: 1.35-1.88). These positive associations remained consistent across different subgroup populations.

Conclusion

Our study suggests a positive and independent association between the TyG index and WRF in the elderly.

Incidence and impact of atrial fibrillation in heart failure patients: real-world data in a large community

AIMS

The objective of the present study is to assess the bidirectional association between heart failure (HF) and atrial fibrillation (AF) using real-world data.

METHODS AND RESULTS

From an electronic health recording with a population of 3 799 885 adult subjects, those with prevalent or incident HF were selected and followed throughout a study period of 5 years. Prevalence and incidence of AF, and their impact in the risk for acute HF hospitalization, worsening renal function, ischaemic and haemorrhagic stroke, and all-cause mortality were identified. We analysed all incident and prevalent patients with HF and AF, 128 086 patients (S1), and subsequently analysed a subset of patients with incident HF and AF, 57 354 patients (S2). We analysed all incident and prevalent patients with HF and AF, 128 086 patients (S1), and subsequently a subset of patients with incident HF and AF, 57 354 patients (S2). The prevalence of AF was 59 906 (46.7%) of the HF patients, while incidence in the S2 was 231/1000 patients/year. In both cohorts, S1 and S2, AF significantly increases the risk of acute heart failure hospitalization [incidence 79.1/1000 and 97.5/1000 patients/year; HR 1.53 (1.48-1.59 95% CI) and HR 1.32 (1.24-1.41 95% CI), respectively], risk of decreased renal function (eGFR reduced by >20%) [66.2/1000 and 94.0/1000 patients/year; HR 1.13 (1.09-1.18 95% CI) and HR 1.22 (1.14-1.31 95% CI), respectively] and all-cause mortality [203/1000 and 294/1000 patients/year; HR 1.62 (1.58-1.65 95% CI) and HR 1.65 (1.59-1.70 95% CI), respectively]. The number of episodes of hospitalization for acute heart failure was also significantly higher in the AF patients (27 623 vs. 10 036, P < 0.001). However, the risk for ischaemic stroke was reduced in the AF subjects [HR 0.66 (0.63-0.74 95% CI)], probably due to the anticoagulant treatment.

CONCLUSIONS

AF is associated with an increment in the risk of episodes of acute heart failure as well as decline of renal function and increment of all-cause mortality.

Prediction and Risk Stratification of Cardiovascular Disease in Diabetic Kidney Disease Patients

Background

Diabetic kidney disease (DKD) patients are facing an extremely high risk of cardiovascular disease (CVD), which is a major cause of death for DKD patients. We aimed to build a deep learning model to predict CVD risk among DKD patients and perform risk stratifying, which could help them perform early intervention and improve personal health management.

Methods

A retrospective cohort study was conducted to assess the risk of the occurrence of composite cardiovascular disease, which includes coronary heart disease, cerebrovascular diseases, congestive heart failure, and peripheral artery disease, in DKD patients. A least absolute shrinkage and selection operator (LASSO) regression was used to perform the variable selection. A deep learning-based survival model called DeepSurv, based on a feed-forward neural network was developed to predict CVD risk among DKD patients. We compared the model performance with the conventional Cox proportional hazards (CPH) model and the Random survival forest (RSF) model using the concordance index (C-index), the area under the curve (AUC), and integrated Brier scores (IBS).

Results

We recruited 890 patients diagnosed with DKD in this retrospective study. During a median follow-up of 10.4 months, there are 289 patients who sustained a subsequent CVD. Seven variables, including age, high density lipoprotein (HDL), hemoglobin (Hb), systolic blood pressure (SBP), smoking status, 24 h urinary protein excretion, and total cholesterol (TC), chosen by LASSO regression were used to develop the predictive model. The DeepSurv model showed the best performance, achieved a C-index of 0.767(95% confidence intervals [CI]: 0.717–0.817), AUC of 0.780(95%CI: 0.721–0.839), and IBS of 0.067 in the validation set. Then we used the cut-off value determined by ROC (receiver operating characteristic) curve to divide the patients into different risk groups. Moreover, the DeepSurv model was also applied to develop an online calculation tool for patients to conduct risk monitoring.

Conclusion

A deep-learning-based predictive model using seven clinical variables can effectively predict CVD risk among DKD patients and perform risk stratification. An online calculator allows its easy implementation.

Sirtuin 7 serves as a promising therapeutic target for cardiorenal diseases

Cardiovascular disorders and associated renal diseases account for the main cause of morbidity and mortality worldwide, necessitating the development of novel effective approaches for the prevention and treatment of cardiorenal diseases. Mammalian sirtuins (SIRTs) function as nicotinamide adenine dinucleotide (NAD+)-dependent protein/histone deacetylases. Seven members of SIRTs share a highly invariant catalytic core domain responsible for the specific enzymatic activity. Intriguingly, the broad distribution of SIRTs and alternative isoforms implicate its distinct functions in diverse cardiac and renal cells and tissue types. Notably, SIRT7 has been shown to exert beneficial effects in cardiorenal physiology and pathophysiology via modulation of senescence, DNA damage repair, ribosomal RNA synthesis, protein biosynthesis, angiogenesis, apoptosis, superoxide generation, cardiorenal metabolism, and dysfunction. Furthermore, SIRT7 has emerged as a critical modulator of a broad range of cellular activities including oxidative stress, inflammation response, endoplasmic reticulum stress, and mitochondrial homeostasis, which are all of great significance in postponing the progression of cardiorenal diseases. More importantly, SIRT7 has been implicated in cardiorenal hypertrophy, fibrosis, remodeling, heart failure, atherosclerosis as well as renal acid-base and electrolyte homeostasis as an essential regulator. In this review, we focus on the involvement in cardiorenal physiology and pathophysiology, diverse actions and underlying mechanisms of the SIRT7 signaling, highlighting its updated research progress in heart failure, atherosclerosis, diabetic nephropathy and other cardiorenal diseases. Targeting SIRT7 signaling could be potentially exploited as a therapeutic strategy aiming to prevent and treat cardiorenal diseases.

Real world data of anticoagulant treatment in non-valvular atrial fibrillation across renal function status

The objective is to assess the impact of anticoagulant treatment in non-valvular atrial fibrillation (AF) and different categories of renal dysfunction in real world. Electronic Health recordings of patients with diagnosis of AF and renal function collected throughout 5 years and classified according to KDIGO categories. Stroke, transitory ischemic attack (TIA), intracranial hemorrhage and all-cause mortality were identified. Anticoagulant treatments during the study period were classified in untreated (never received therapy), VKA, NOAC and Aspirin. The risk of events was calculated by Cox-proportional hazard models adjusted by confounders. A total of 65,734 patients with AF, mean age 73.3 ± 10.49 years old and 47% females and follow-up of 3.2 years were included. KDIGO classification were: G1 33,903 (51.6%), G2 17,456 (26.6%), G3 8024 (12.2%) and G4 6351 (9.7%). There were 8592 cases of stroke and TIA, 437 intracranial hemorrhage, and 9603 all-cause deaths (incidence 36, 2 and 38 per 103 person/year, respectively). 4.1% of patients with CHA2DS2-VASc Score 2 or higher did not receive anticoagulant therapy. Risk of stroke, TIA, and all-cause mortality increased from G1 to G4 groups. Anticoagulant treatments reduced the risk of events in the four categories, but NOAC seemed to offer significantly better protection. Renal dysfunction increases the risk of events in AF and anticoagulant treatments reduced the risk of stroke and all-cause mortality, although NOAC were better than VKA. Efforts should be done to reduce the variability in the use of anticoagulants even in this high risk group.

The anti-aging factor Klotho protects against acquired long QT syndrome induced by uremia and promoted by fibroblast growth factor 23

BACKGROUND

Chronic kidney disease (CKD) is associated with increased propensity for arrhythmias. In this context, ventricular repolarization alterations have been shown to predispose to fatal arrhythmias and sudden cardiac death. Between mineral bone disturbances in CKD patients, increased fibroblast growth factor (FGF) 23 and decreased Klotho are emerging as important effectors of cardiovascular disease. However, the relationship between imbalanced FGF23-Klotho axis and the development of cardiac arrhythmias in CKD remains unknown.

METHODS

We carried out a translational approach to study the relationship between the FGF23-Klotho signaling axis and acquired long QT syndrome in CKD-associated uremia. FGF23 levels and cardiac repolarization dynamics were analyzed in patients with dialysis-dependent CKD and in uremic mouse models of 5/6 nephrectomy (Nfx) and Klotho deficiency (hypomorphism), which show very high systemic FGF23 levels.

RESULTS

Patients in the top quartile of FGF23 levels had a higher occurrence of very long QT intervals (> 490 ms) than peers in the lowest quartile. Experimentally, FGF23 induced QT prolongation in healthy mice. Similarly, alterations in cardiac repolarization and QT prolongation were observed in Nfx mice and in Klotho hypomorphic mice. QT prolongation in Nfx mice was explained by a significant decrease in the fast transient outward potassium (K⁺) current (I_tof), caused by the downregulation of K⁺ channel 4.2 subunit (Kv4.2) expression. Kv4.2 expression was also significantly reduced in ventricular cardiomyocytes exposed to FGF23. Enhancing Klotho availability prevented both long QT prolongation and reduced I_tof current. Likewise, administration of recombinant Klotho blocked the downregulation of Kv4.2 expression in Nfx mice and in FGF23-exposed cardiomyocytes.

CONCLUSION

The FGF23-Klotho axis emerges as a new therapeutic target to prevent acquired long QT syndrome in uremia by minimizing the predisposition to potentially fatal ventricular arrhythmias and sudden cardiac death in patients with CKD.

Clinical characteristics of COVID-19 patients with complications: implications for management

Background:

A novel coronavirus disease 2019 (COVID-19) has caused outbreaks worldwide, and the number of cases is rapidly increasing through human-to-human transmission. Because of the greater transmission capacity and possible subsequent multi-organ damage caused by the virus, it is crucial to understand precisely and manage COVID-19 patients. However, the underlying differences in the clinical features of COVID-19 with and without comorbidities are not fully understood.

Aim:

The objective of this study was to identify the clinical features of COVID-19 patients with and without complications to guide treatment and predict the prognosis.

Method:

We collected the clinical characteristics of COVID-19 patients with and without different complications, including hypertension, cardiovascular disease and diabetes. Next, we performed a baseline comparison of each index and traced the dynamic changes in these factors during hospitalization to explore the potential associations.

Result:

A clinical index of differential expression was used for the regression to select top-ranking factors. The top-ranking clinical characteristics varied in each subgroup, such as indices of liver function, renal function and inflammatory markers. Among them, the indices of renal function were highly ranked in all subgroups and displayed significant differences during hospitalization.

Conclusion:

Organ functions of COVID-19 patients, particularly renal function, should be cautiously taken care of during management and might be a crucial factor for a poor prognosis of these patients with complications.