Estimated glomerular filtration rate and albuminuria for prediction of cardiovascular outcomes: a collaborative meta-analysis of individual participant data

The association between hypertriglyceridemic-waist phenotype and chronic kidney disease: a cohort study and meta-analysis

Evidence on the association between hypertriglyceridemic-waist phenotype (HTGW) and chronic kidney disease (CKD) is limited and inconsistent. We aimed to explore such association among 7406 Chinese aged ≥ 45 years in a cohort setting, followed by a meta-analysis. Participants were categorized into four phenotypes: NTNW (normal triglycerides and normal waist circumference), NTGW (isolated enlarged waist circumference), HTNW (isolated high triglycerides), and HTGW (high triglycerides and enlarged waist circumference). We used multivariate logistic regression to determine the association between different phenotypes and risk of CKD in the cohort study. For meta-analysis, we searched relevant studies from Embase, Medline, PubMed, and Web of Science from dataset inception up to May 1, 2021. A random-effect model was used to estimate the pooled effect and I² statistic was applied to evaluate heterogeneity. In the cohort study, compared to the NTNW phenotype, HTGW (OR 1.82, 95% CI 1.32 to 2.51, p < 0.01) and NTGW (OR 1.48, 95% CI 1.13 to 1.94, p = 0.004) were significantly associated with CKD risk after 4 years follow-up, but not for the HTNW phenotype. The meta-analysis also showed a positive association between HTGW phenotype and CKD risk (pooled OR 1.53, 95% CI 1.31 to 1.79, I² = 62.4%). Assessment of triglyceridemic-waist phenotypes might help to identify individuals with high-risk of developing CKD.

Nonlinear causal effects of estimated glomerular filtration rate on myocardial infarction risks: Mendelian randomization study

BACKGROUND

Previous observational studies suggested that a reduction in estimated glomerular filtration rate (eGFR) or a supranormal eGFR value was associated with adverse cardiovascular risks. However, a previous Mendelian randomization (MR) study under the linearity assumption reported null causal effects from eGFR on myocardial infarction (MI) risks. Further investigation of the nonlinear causal effect of kidney function assessed by eGFR on the risk of MI by nonlinear MR analysis is warranted.

METHODS

In this MR study, genetic instruments for log-eGFR based on serum creatinine were developed from European samples included in the CKDGen genome-wide association study (GWAS) meta-analysis (N=567,460). Alternate instruments for log-eGFR based on cystatin C were developed from a GWAS of European individuals that included the CKDGen and UK Biobank data (N=460,826). Nonlinear MR analysis for the risk of MI was performed using the fractional polynomial method and the piecewise linear method on data from individuals of white British ancestry in the UK Biobank (N=321,024, with 12,205 MI cases).

RESULTS

Nonlinear MR analysis demonstrated a U-shaped (quadratic P value < 0.001) association between MI risk and genetically predicted eGFR (creatinine) values, as MI risk increased as eGFR declined in the low eGFR range and the risk increased as eGFR increased in the high eGFR range. The results were similar even after adjustment for clinical covariates, such as blood pressure, diabetes mellitus, dyslipidemia, or urine microalbumin levels, or when genetically predicted eGFR (cystatin C) was included as the exposure.

CONCLUSION

Genetically predicted eGFR is significantly associated with the risk of MI with a parabolic shape, suggesting that kidney function impairment, either by reduced or supranormal eGFR, may be causally linked to a higher MI risk.

Peritoneal Dialysis for Potential Kidney Transplant Recipients: Pride or Prejudice?

Kidney transplantation (KT) is recognized as the gold-standard of treatment for patients with end-stage renal disease. Additionally, it has been demonstrated that receiving a pre-emptive KT ensures the best recipient and graft survivals. However, due to an overwhelming discrepancy between the organs available and the patients on the transplant waiting list, the vast majority of transplant candidates require prolonged periods of dialysis before being transplanted. For many years, peritoneal dialysis (PD) and hemodialysis (HD) have been considered competitive renal replacement therapies (RRT). This dualistic vision has recently been questioned by evidence suggesting that an individualized and flexible approach may be more appropriate. In fact, tailored and cleverly planned changes between different RRT modalities, according to the patient’s needs and characteristics, are often needed in order to achieve the best results. While home HD is still under scrutiny in this particular setting, current data seems to favor the use of PD over in-center HD in patients awaiting a KT. In this specific population, the demonstrated advantages of PD are superior quality of life, longer preservation of residual renal function, lower incidence of delayed graft function, better recipient survival, and reduced cost.

Heart Disease and Stroke Statistics-2022 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2022 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population and an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, and the global burden of cardiovascular disease and healthy life expectancy.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

The relationship between urinary albumin to creatinine ratio and all-cause mortality in the elderly population in the Chinese community: a 10-year follow-up study

BACKGROUND

In patients with diabetes and hypertension, proteinuria is independently associated with all-cause death. However, in the general population, urinary albumin to creatinine ratio (UACR) is less used to predict all-cause mortality. When the urinary albumin to creatinine ratio is within the normal range (UACR< 30 mg/g), the clinical relevance of an increased urinary albumin excretion rate is still debated. We studied the relationship between UACR and all-cause mortality in community populations, and compared UACR groups within the normal range.

METHODS

The participants were the inhabitants from the Wanshoulu community in Beijing, China. The average age is 71.48 years, and the proportion of women is 60.1%. A total of 2148 people completed random urine samples to determine the urinary albumin to creatinine ratio (UACR). The subjects were divided into three groups according to UACR: Group 1 (UACR< 10 mg/g), Group 2 (10 mg/g < UACR< 30 mg/g), Group 3 (UACR> 30 mg/g). We used Kaplan-Meier survival analysis and Cox regression model to verify the relationship between UACR and all-cause mortality.

RESULTS

At an average follow-up of 9.87 years (718,407.3 years), the total mortality rate were 183.4/1000. In the Cox proportional hazards model, after adjusting for possible confounders, those with normal high-value UACR (group 2) showed a higher all-cause mortality than those with normal low-value UACR (group 1) [hazard ratio (HR) 1.289, 95% confidence interval (CI) 1.002 ~ 1.659 for all-cause mortality]. Those with proteinuria (group 3) showed a higher all-cause mortality than those with normal low-value UACR (group 1) [hazard ratio (HR) 1.394, 95% confidence interval (CI) 1.020 ~ 1.905 for all-cause mortality].

CONCLUSION

Urinary albumin to creatinine ratio is an important risk factor for all-cause death in community population. Even if it is within the normal range (UACR< 30 mg/g), it occurs in people with high normal value (10 mg/g < UACR< 30 mg/g), the risk of all-cause death will also increase.

Association of accelerometer-measured physical activity with kidney function in a Japanese population: the DOSANCO Health Study

BACKGROUND

Sedentary behavior and decreased physical activity are associated with reduced kidney function, yet most evidence is based on self-reported physical activity. This study investigated the association between accelerometer-based physical activity level and kidney function in a general Japanese population.

METHODS

A cross-sectional study was conducted in 440 community-dwelling Japanese participants, aged 35-79 years. Time (min/d) was assessed for the following types of physical activity: sedentary behavior, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA). Kidney function was assessed using estimated glomerular filtration rate (eGFR). A linear regression model was employed to calculate the β coefficient of eGFR for a 60-min/d increase in sedentary behavior and LPA and a 10-min/d increase in MVPA. A logistic regression model was used to calculate the odds ratio for low eGFR (< 60 versus ≥60 mL/min/1.73m²) for a 60-min/d or 10-min/d increase in each physical activity type.

RESULTS

MVPA time and eGFR were positively associated in both men and women, after adjusting for age, body mass index, and other clinical characteristics (Men: β, 0.91; P = 0.021; Women: β, 0.70; P = 0.034). In women, sedentary behavior and eGFR were inversely associated after adjusting for the same factors (β, - 1.06; P = 0.048). The odds ratio (95% confidence interval) for low eGFR associated with a 60-min increase in sedentary behavior was 1.65 (1.07-2.55) after adjusting for the same factors in women.

CONCLUSION

Longer sedentary behavior and shorter MVPA time were associated with lower kidney function in the Japanese population.

The Association Between Hypertriglyceridemic-Waist Phenotype and Chronic Kidney Disease in Patients with Type 2 Diabetes: A Cross-Sectional METAL Study

BACKGROUND

The aim of this study was measuring the association between the hypertriglyceridemic-waist (HTGW) phenotype and chronic kidney disease in a large type 2 diabetes population.

METHODS

A total of 4254 diabetic patients from the cross-sectional Environmental Pollutant Exposure and Metabolic Diseases in Shanghai (METAL) study were enrolled. The hypertriglyceridemic-waist (HTGW) phenotype was defined as the presence of an elevated waist circumference (WC) and elevated triglyceride (TG) concentration. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m² or urinary albumin creatinine ratio (uACR) more than 30 mg/g. Linear and multiple logistic regression models were used for measuring the association between HTGW phenotype and chronic kidney disease.

RESULTS

The prevalence of CKD was 29% and 35.8% in total participants and participants with HTGW phenotype, respectively. Subjects in the HTGW phenotype group were more likely to have CKD (OR 1.47, 95% CI: 1.11, 1.95) compared with subjects in the normal waist circumference and normal triglycerides (NTNW) group. HTGW phenotype was both associated with the increasing risk of decreased eGFR (OR 1.31, 95% CI: 1.02, 1.75) and elevated uACR (OR 1.57, 95% CI: 1.18, 2.11). Furthermore, the stratified analysis showed that the strongest positive association between HTGW phenotype and CKD presence was found in the subgroup of presence of hypertension. The associations were all fully adjusted for age, sex, BMI, current smoking, current drinking and other confounding factors.

CONCLUSION

Our study suggested a positive association between the HTGW phenotype and CKD in Chinese type 2 diabetes patients. Further prospective studies are needed to confirm our findings and to investigate the underlying biological mechanisms.

Association of Kidney Function with Risk of Incident Dementia: A Prospective Cohort Study of 275,167 UK Biobank Participants

BACKGROUND

Previous studies have reported inconsistent associations between chronic kidney disease (CKD) and dementia.

OBJECTIVE

To evaluate whether CKD is a risk factor for dementia and compare the performance of different measures of calculating estimated glomerular filtration rate (eGFR).

METHODS

275,167 participants from UK Biobank were included and eGFR at baseline was calculated using serum creatinine (eGFRcr), cystatin C (eGFRcys), and creatinine-cystatin C equations (eGFRcr-cys). Restricted cubic splines and Cox regression models were performed to assess the relationship of eGFR with all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD).

RESULTS

We observed a U-shaped relationship between each eGFR and risk of all-cause dementia and VaD, with eGFRcys and eGFRcr-cys showing a closer linkage (peGFRcys <0.0001, peGFRcrhboxcys<0.0001 and peGFRcr = 0.0001). Lower and supranormal eGFR were related to increased risk of all-cause dementia. Compared to the reference category of 90-104 ml/min/1.73 m2, adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of all-cause dementia for eGFRcr-cys 30-59, <30, and ≥105 ml/min/1.73 m2 were 1.26 (95% CI [1.05-1.50], p = 0.012), 2.62 (95% CI [1.54-4.47], p < 0.001), and 1.41 (95% CI [1.17-1.70], p < 0.001). No statistically significant association was observed between eGFR with risk of AD.

CONCLUSION

This prospective study identified impaired kidney function as a critical risk factor for dementia and noted the application of cystatin C strengthened the relationship between CKD and dementia, underlining the significant value of preserving kidney function to reduce the risk of dementia and considering cystatin C measurement as part of clinical practice.

Discovery of novel eGFR-associated multiple independent signals using a quasi-adaptive method

A decreased estimated glomerular filtration rate (eGFR) leading to chronic kidney disease is a significant public health problem. Kidney function is a heritable trait, and recent application of genome-wide association studies (GWAS) successfully identified multiple eGFR-associated genetic loci. To increase statistical power for detecting independent associations in GWAS loci, we improved our recently developed quasi-adaptive method estimating SNP-specific alpha levels for the conditional analysis, and applied it to the GWAS meta-analysis results of eGFR among 783,978 European-ancestry individuals. Among known eGFR loci, we revealed 19 new independent association signals that were subsequently replicated in the United Kingdom Biobank (n = 408,608). These associations have remained undetected by conditional analysis using the established conservative genome-wide significance level of 5 × 10^-8. Functional characterization of known index SNPs and novel independent signals using colocalization of conditional eGFR association results and gene expression in cis across 51 human tissues identified two potentially causal genes across kidney tissues: TSPAN33 and TFDP2, and three candidate genes across other tissues: SLC22A2, LRP2, and CDKN1C. These colocalizations were not identified in the original GWAS. By applying our improved quasi-adaptive method, we successfully identified additional genetic variants associated with eGFR. Considering these signals in colocalization analyses can increase the precision of revealing potentially functional genes of GWAS loci.

CKD: The burden of disease invisible to research funders

The uptake of the current concept of chronic kidney disease (CKD) by the public, physicians and health authorities is low. Physicians still mix up CKD with chronic kidney insufficiency or failure. In a recent manuscript, only 23% of participants in a cohort of persons with CKD had been diagnosed by their physicians as having CKD while 29% has a diagnosis of cancer and 82% had a diagnosis of hypertension. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. A prevalent view is that for those in whom kidneys fail, the problem is "solved" by dialysis or kidney transplantation. However, the main burden of CKD is accelerated aging and all-cause and cardiovascular premature death. CKD is the most prevalent risk factor for lethal COVID-19 and the factor that most increases the risk of death in COVID-19, after old age. Moreover, men and women undergoing KRT still have an annual mortality which is 10-100-fold higher than similar age peers, and life expectancy is shortened by around 40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth global cause of death by 2040 and the second cause of death in Spain before the end of the century, a time when 1 in 4 Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded CIBER network research structure in Spain. Leading Spanish kidney researchers grouped in the kidney collaborative research network REDINREN have now applied for the RICORS call of collaborative research in Spain with the support of the Spanish Society of Nephrology, ALCER and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true. However, only the highest level of research funding through the CIBER will allow to adequately address the issue before it is too late.

Time-Updated Changes in Estimated GFR and Proteinuria and Major Adverse Cardiac Events: Findings from the Chronic Renal Insufficiency Cohort (CRIC) Study

RATIONALE & OBJECTIVE

Evaluating repeated measures of estimated glomerular filtration rate (eGFR) and urinary protein-creatinine ratio (UPCR) over time may enhance our ability to understand the association between changes in kidney parameters and cardiovascular disease risk.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Annual visit data from 2,438 participants in the Chronic Renal Insufficiency Cohort (CRIC).

EXPOSURES

Average and slope of eGFR and UPCR in time-updated, 1-year exposure windows.

OUTCOMES

Incident heart failure, atherosclerotic cardiovascular disease events, death, and a composite of incident heart failure, atherosclerotic cardiovascular disease events, and death.

ANALYTICAL APPROACH

A landmark analysis, a dynamic approach to survival modeling that leverages longitudinal, iterative profiles of laboratory and clinical information to assess the time-updated 3-year risk of adverse cardiovascular outcomes.

RESULTS

Adjusting for baseline and time-updated covariates, every standard deviation lower mean eGFR (19mL/min/1.73m²) and declining slope of eGFR (8mL/min/1.73m² per year) were independently associated with higher risks of heart failure (hazard ratios [HRs] of 1.82 [95% CI, 1.39-2.44] and 1.28 [95% CI, 1.12-1.45], respectively) and the composite outcome (HRs of 1.32 [95% CI, 1.11-1.54] and 1.11 [95% CI, 1.03-1.20], respectively). Every standard deviation higher mean UPCR (136mg/g) and increasing UPCR (240mg/g per year) were also independently associated with higher risks of heart failure (HRs of 1.58 [95% CI, 1.28-1.97] and 1.20 [95% CI, 1.10-1.29], respectively) and the composite outcome (HRs of 1.33 [95% CI, 1.17-1.50] and 1.12 [95% CI, 1.06-1.18], respectively).

LIMITATIONS

Limited generalizability of annual eGFR and UPCR assessments; several biomarkers for cardiovascular disease risk were not available annually.

CONCLUSIONS

Using the landmark approach to account for time-updated patterns of kidney function, average and slope of eGFR and proteinuria were independently associated with 3-year cardiovascular risk. Short-term changes in kidney function provide information about cardiovascular risk incremental to level of kidney function, representing possible opportunities for more effective management of patients with chronic kidney disease.

Association between metabolic scores for visceral fat and chronic kidney disease: A cross-sectional study

INTRODUCTION

Central obesity is closely linked to the risk of chronic kidney disease (CKD). This study aimed to evaluate the association between the novel central obesity index- metabolic score for visceral fat (METS-VF) and the risk of CKD in a Chinese population, and to compare its ability to predict CKD with other central obesity indices including waist circumference (WC), waist-to-height ratio (WHtR), lipid accumulation product (LAP), visceral adiposity index (VAI), a body shape index (ABSI), body roundness index (BRI), and cardiometabolic index (CMI).

METHODS

This cross-sectional study included 8866 individuals from China. Demographic information, lifestyle data, and medical history data were collected, and physical examinations, anthropometric measurements and laboratory tests were performed for each participant. CKD was defined as an estimated GFR< 60 ml/min/1.73m². Multivariate logistic regression models were used to evaluate the association between the METS-VF and the prevalence of CKD. Receiver operating characteristic (ROC) analyses were performed to assess and compare the predictive abilities of the central obesity indices and determine the optimal cut-off points.

RESULTS

A graded increase in the prevalence of CKD was observed with increasing METS-VF tertiles. Moreover, the METS-VF was independently associated with the risk of CKD after adjustment for current smoking, current drinking, physical activity level, diabetes, hypertension, CVD history and BMI. Compared with participants with a METS-VF in the lowest tertile, the multivariate-adjusted ORs and 95% CIs for participants with a METS-VF in the highest tertile were 3.943 (2.435-6.385) in the overall population, 3.585 (1.585-8.109) for men and 4.627 (2.485-8.616) for women. Significant interactions were found between the METS-VF and the risk of CKD by age (P value for interaction = 0.023). In ROC analysis, the METS-VF had a higher AUC value than other indices for predicting CKD in men and had comparable or higher AUC than other indices for women. For predicting CKD, the optimal cut-off value of the METS-VF was 6.891 for men and 6.744 for women. The METS-VF yielded the greatest Youden index among all indices for both sexes.

CONCLUSION

A higher METS-VF was independently associated with a greater risk of CKD. The METS-VF can be a useful clinical indicator for identifying CKD, as it had superior predictive power for CKD when compared with other central obesity indices.

Exploring New Kingdoms: The Role of Extracellular Vesicles in Oxi-Inflamm-Aging Related to Cardiorenal Syndrome

The incidence of age associated chronic diseases has increased in recent years. Although several diverse causes produce these phenomena, abundant evidence shows that oxidative stress plays a central role. In recent years, numerous studies have focused on elucidating the role of oxidative stress in the development and progression of both aging and chronic diseases, opening the door to the discovery of new underlying mechanisms and signaling pathways. Among them, senolytics and senomorphics, and extracellular vesicles offer new therapeutic strategies to slow the development of aging and its associated chronic diseases by decreasing oxidative stress. In this review, we aim to discuss the role of extracellular vesicles in human cardiorenal syndrome development and their possible role as biomarkers, targets, or vehicles of drugs to treat this syndrome.

OMICS in Chronic Kidney Disease: Focus on Prognosis and Prediction

Chronic kidney disease (CKD) patients are characterized by a high residual risk for cardiovascular (CV) events and CKD progression. This has prompted the implementation of new prognostic and predictive biomarkers with the aim of mitigating this risk. The ‘omics’ techniques, namely genomics, proteomics, metabolomics, and transcriptomics, are excellent candidates to provide a better understanding of pathophysiologic mechanisms of disease in CKD, to improve risk stratification of patients with respect to future cardiovascular events, and to identify CKD patients who are likely to respond to a treatment. Following such a strategy, a reliable risk of future events for a particular patient may be calculated and consequently the patient would also benefit from the best available treatment based on their risk profile. Moreover, a further step forward can be represented by the aggregation of multiple omics information by combining different techniques and/or different biological samples. This has already been shown to yield additional information by revealing with more accuracy the exact individual pathway of disease.

Risk for subsequent hypertension and cardiovascular disease after living kidney donation: is it clinically relevant?

The first successful live donor kidney transplant was performed in 1954. Receiving a kidney transplant from a live kidney donor remains the best option for increasing both life expectancy and quality of life in patients with end-stage kidney disease. However, ever since 1954, there have been multiple questions raised on the ethics of live kidney donation in terms of negative impacts on donor life expectancy. Given the close relationship between reduced kidney function in patients with chronic kidney disease (CKD) and hypertension, cardiovascular disease and cardiovascular mortality, information on the impact of kidney donation on these is particularly relevant. In this article, we review the existing evidence, focusing on the more recent studies on the impact of kidney donation on all-cause mortality, cardiovascular mortality, cardiovascular disease and hypertension, as well as markers of cardiovascular damage including arterial stiffness and uraemic cardiomyopathy. We also discuss the similarities and differences between the pathological reduction in renal function that occurs in CKD, and the reduction in renal function that occurs because of a donor nephrectomy. Kidney donors perform an altruistic act that benefits individual patients as well as the wider society. They deserve to have high-quality evidence on which to make informed decisions.

Albuminuria predicts worsening renal function after transcatheter aortic valve replacement

BACKGROUND

The impact of albuminuria on worsening renal function (WRF) and clinical outcomes after transcatheter aortic valve replacement (TAVR) is unknown.

METHODS

Overall, 142 patients who underwent TAVR for severe aortic stenosis were divided into two groups based on the preoperative urinary albumin-to-creatinine ratio (ACR): high (ACR ≥30 mg/g) and low (ACR <30 mg/g). The incidence of WRF (an absolute increase in serum creatinine level of ≥0.3 mg/dL or ≥1.5-fold from baseline or dialysis initiation) at 6 months after TAVR and the incidence of all-cause death and heart failure readmission during follow-up were investigated.

RESULTS

Half of the examined patients [n=71/142 (50.0%)] had a high ACR. Patients with a high ACR more frequently had WRF at 6 months than those with a low ACR (17.6% vs. 2.9%, p=0.004). Multivariate analysis showed a high ACR was independently associated with WRF (odds ratio, 7.76; 95% confidence interval, 1.62-37.30; p=0.01), whereas baseline estimated glomerular filtration rate <60 mL/min/1.73m² was not (odds ratio, 0.34; 95% confidence interval, 0.08-1.50; p=0.15). Patients with a high ACR had a higher risk of composite outcomes of all-cause death and heart failure readmission (p=0.002).

CONCLUSIONS

Preoperative albuminuria (ACR ≥30 mg/g) was independently associated with WRF at 6 months after TAVR. Furthermore, patients with an ACR ≥30 mg/g had higher risks of all-cause death and heart failure readmission than those with an ACR <30 mg/g.

Selection of 51 predictors from 13,782 candidate multimodal features using machine learning improves coronary artery disease prediction

Current cardiovascular risk assessment tools use a small number of predictors. Here, we study how machine learning might: (1) enable principled selection from a large multimodal set of candidate variables and (2) improve prediction of incident coronary artery disease (CAD) events. An elastic net-based Cox model (ML4HEN-COX) trained and evaluated in 173,274 UK Biobank participants selected 51 predictors from 13,782 candidates. Beyond most traditional risk factors, ML4HEN-COX selected a polygenic score, waist circumference, socioeconomic deprivation, and several hematologic indices. A more than 30-fold gradient in 10-year risk estimates was noted across ML4HEN-COX quintiles, ranging from 0.25% to 7.8%. ML4HEN-COX improved discrimination of incident CAD (C-statistic = 0.796) compared with the Framingham risk score, pooled cohort equations, and QRISK3 (range 0.754-0.761). This approach to variable selection and model assessment is readily generalizable to a broad range of complex datasets and disease endpoints.

Meta-analyses identify DNA methylation associated with kidney function and damage

Chronic kidney disease is a major public health burden. Elevated urinary albumin-to-creatinine ratio is a measure of kidney damage, and used to diagnose and stage chronic kidney disease. To extend the knowledge on regulatory mechanisms related to kidney function and disease, we conducted a blood-based epigenome-wide association study for estimated glomerular filtration rate (n = 33,605) and urinary albumin-to-creatinine ratio (n = 15,068) and detected 69 and seven CpG sites where DNA methylation was associated with the respective trait. The majority of these findings showed directionally consistent associations with the respective clinical outcomes chronic kidney disease and moderately increased albuminuria. Associations of DNA methylation with kidney function, such as CpGs at JAZF1, PELI1 and CHD2 were validated in kidney tissue. Methylation at PHRF1, LDB2, CSRNP1 and IRF5 indicated causal effects on kidney function. Enrichment analyses revealed pathways related to hemostasis and blood cell migration for estimated glomerular filtration rate, and immune cell activation and response for urinary albumin-to-creatinineratio-associated CpGs.

Nephron overload as a therapeutic target to maximize kidney lifespan

Kidney lifespan is a patient-oriented outcome that provides much needed context for understanding chronic kidney disease (CKD). Nephron endowment, age-associated decline in nephron number, kidney injury history and the intrinsic capacity of nephrons to adapt to haemodynamic and metabolic overload vary widely within the population. Defining percentiles of kidney function might therefore help to predict individual kidney lifespan and distinguish healthy ageing from progressive forms of CKD. In response to nephron loss, the remaining nephrons undergo functional and structural adaptations to meet the ongoing haemodynamic and metabolic demands of the organism. When these changes are no longer sufficient to maintain kidney cell homeostasis, remnant nephron demise occurs and CKD progression ensues. An individual's trajectory of glomerular filtration rate and albuminuria reflects the extent of nephron loss and adaptation of the remaining nephrons. Nephron overload represents the final common pathway of CKD progression and is largely independent of upstream disease mechanisms. Thus, interventions that efficiently attenuate nephron overload in early disease stages can protect remnant kidney cells and nephrons, and delay CKD progression. This Review provides a conceptual framework for individualized diagnosis, monitoring and treatment of CKD with the goal of maximizing kidney lifespan.

Fibroblast Growth Factor-23-Klotho Axis in Cardiorenal Syndrome: Mediators and Potential Therapeutic Targets

Cardiorenal syndrome (CRS) is a complex disorder that refers to the category of acute or chronic kidney diseases that induce cardiovascular disease, and inversely, acute or chronic heart diseases that provoke kidney dysfunction. There is a close relationship between renal and cardiovascular disease, possibly due to the presence of common risk factors for both diseases. Thus, it is well known that renal diseases are associated with increased risk of developing cardiovascular disease, suffering cardiac events and even mortality, which is aggravated in those patients with end-stage renal disease or who are undergoing dialysis. Recent works have proposed mineral bone disorders (MBD) as the possible link between kidney dysfunction and the development of cardiovascular outcomes. Traditionally, increased serum phosphate levels have been proposed as one of the main factors responsible for cardiovascular damage in kidney patients. However, recent studies have focused on other MBD components such as the elevation of fibroblast growth factor (FGF)-23, a phosphaturic bone-derived hormone, and the decreased expression of the anti-aging factor Klotho in renal patients. It has been shown that increased FGF-23 levels induce cardiac hypertrophy and dysfunction and are associated with increased cardiovascular mortality in renal patients. Decreased Klotho expression occurs as renal function declines. Despite its expression being absent in myocardial tissue, several studies have demonstrated that this antiaging factor plays a cardioprotective role, especially under elevated FGF-23 levels. The present review aims to collect the recent knowledge about the FGF-23-Klotho axis in the connection between kidney and heart, focusing on their specific role as new therapeutic targets in CRS.

Association between pulse pressure and progression of chronic kidney disease

The aim of this study was to investigate the association between pulse pressure (PP) and chronic kidney disease (CKD) progression among the general population in Japan. We conducted a population-based cohort study of the residents of Iki Island, Nagasaki, Japan, from 2008 to 2018. We identified 1042 participants who had CKD (estimated glomerular filtration rate(eGFR) < 60 mL/min/1.73 m2 or the presence of proteinuria) at baseline. Cox's proportional hazard model was used to evaluate the association between PP and progression of CKD. During a 4.66-year mean follow-up, there were 241 cases of CKD progression (incident rate: 49.8 per 1000 person-years). A significant increase existed in CKD progression per 10 mmHg of PP elevation, even when adjusted for confounding factors [adjusted hazard ratio 1.17 (1.06-1.29) p < 0.001]. Similar results were obtained even after dividing PP into quartiles [Q2: 1.14 (0.74-1.76), Q3: 1.35 (0.88-2.06), Q4: 1.87 (1.23-2.83) p = 0.003 for trend]. This trend did not change significantly irrespective of baseline systolic or diastolic blood pressures. PP remained a potential predictive marker, especially for eGFR decline. In conclusion, we found a significant association between PP and CKD progression. PP might be a potential predictive marker for CKD progression.

Sodium-glucose cotransporter 2 inhibitors: renal outcomes according to baseline albuminuria

Sodium-glucose co-transporter 2 inhibitors (SGLT2is) reduce albuminuria and hard renal outcomes (decline of renal function, renal replacement therapy and renal death) in patients with/without type 2 diabetes at high cardiovascular or renal risk. The question arises whether baseline albuminuria also influences renal outcomes with SGLT2is as reported with renin-angiotensin-aldosterone system inhibitors. Post hoc analyses focusing on albuminuria and renal outcomes of four cardiovascular outcome trials [EMPA-REG OUTCOME (Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients), CANVAS (Canagliflozin Cardiovascular Assessment Study), DECLARE-TIMI 58 (Multicenter Trial to Evaluate the Effect of Dapagliflozin on the Incidence of Cardiovascular Events-Thrombolysis in Myocardial Infarction 58) and VERTIS CV (Evaluation of Ertugliflozin Efficacy and Safety Cardiovascular Outcomes Trial)] and some renal data from two heart failure trials [Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF) and EMPEROR-Reduced (Empagliflozin Outcome Trial in Patients With Chronic Heart Failure With Reduced Ejection Fraction)] showed renal protection with SGLT2is without significant interaction (P > 0.10) when comparing renal outcomes according to baseline levels (A1, A2 and A3) of urinary albumin:creatinine ratio (UACR), a finding confirmed in a dedicated meta-analysis. Two trials [CREDENCE (Evaluation of the Effects of Canagliflozin on Renal and Cardiovascular Outcomes in Participants With Diabetic Nephropathy) and DAPA-CKD (Dapagliflozin and Prevention of Adverse Outcomes in Chronic Kidney Disease)] specifically recruited patients with CKD and UACRs of 200-5000 mg/g. A post hoc analysis of CREDENCE that distinguished three subgroups according to UACR (300-1000, 1000-3000 and >3000 mg/g) showed a greater relative reduction in UACR in patients with lower baseline albuminuria levels (P for interaction = 0.03). Patients with a UACR >1000 mg/g showed a significantly greater reduction in absolute (P for interaction < 0.001) and a trend in relative (P for interaction = 0.25) risk of renal events versus those with lower UACR levels. In conclusion, baseline UACR levels do not significantly influence the nephroprotection by SGLT2is, yet the greater protection in patients with very high UACRs in CREDENCE deserves confirmation. The underlying mechanisms of renal protection with SGLT2is might be different in patients with or without (high) UACR.

Epidemiological characteristics of diabetic kidney disease in Taiwan

Diabetic kidney disease (DKD) is a critical microvascular complication of diabetes. With the continuous increase in the prevalence of diabetes since 2000, the prevalence of DKD has also been increasing in past years. The prevalence of DKD among individuals with type 2 diabetes in Taiwan increased from 13.32% in 2000 to 17.92% in 2014. The cumulative incidence of DKD among individuals with type 1 diabetes in Taiwan was higher than 30% during 1999-2012. DKD is the leading cause of end-stage renal disease (ESRD), with a prevalence of approximately 45% in a population on chronic dialysis in Taiwan. Among individuals with type 2 diabetes, the prevalence of ESRD in the receipt of dialysis also increased from 1.32% in 2005 to 1.47% in 2014. Risk factors for DKD development are age, race, family history, hyperglycemia, hypertension, dyslipidemia, dietary patterns, and lifestyles. Prognostic factors that aggravate DKD progression include age, family history, sex, glycemic control, blood pressure (BP), microvascular complications, and atherosclerosis. This review summarizes updated information on the onset and progression of DKD, particularly in the Taiwanese population. Translating these epidemiological features is essential to optimizing the kidney care and improving the prognosis of DKD in Asian populations.

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.

Association of left ventricular hypertrophy and functional impairment with cardiovascular outcomes and mortality among patients with chronic kidney disease, results from the C-STRIDE study

AIM

Left ventricular hypertrophy and impaired systolic and diastolic function are commonly seen in patients with chronic kidney disease (CKD), but relationships between the disorders and cardiovascular outcomes are not well established among the patients.

METHODS

Totally, 2020 patients with CKD Stages 1-4 were used in the analysis. Left ventricular hypertrophy was defined by left ventricular mass index >49.2 g/m^2.7 in men and > 46.7 g/m^2.7 in women. Incident heart failure, non-heart failure cardiovascular events, and all-cause mortality were recorded longitudinally. Cox proportional hazards regression model was used to evaluate the association between the echo parameters and the outcomes, with death treated as the competing risk event for the cardiovascular events.

RESULTS

After a median follow-up of 4.5 years, 53 heart failure, 76 non-heart failure cardiovascular events and 82 deaths occurred. No overall association was found between left ventricular hypertrophy and subsequent heart failure, but the relationship was significant among patients with no diabetes with the multivariable adjusted hazard ratio of 3.66 (95% confidence interval: 1.42-9.46). Ejection fraction<55% was associated with both heart failure and non-heart failure cardiovascular events with hazard ratios of 3.16 (1.28-7.77) and 2.76 (1.08-7.04), respectively. E/A ratio ≤ 0.75 was associated with non-heart failure cardiovascular events [hazard ratio = 2.03 (1.09-3.80)], compared with E/A ratio of 0.76-1.49.

CONCLUSION

Associations of reduced left ventricular ejection fraction with both heart failure and non-heart failure cardiovascular events and of impaired left ventricular diastolic function with non-heart failure cardiovascular events were validated in a Chinese cohort of CKD.

The Glomerular Filtration Rate: From the Diagnosis of Kidney Function to a Public Health Tool

The prevalence of chronic kidney disease (CKD) continues to increase worldwide, as well as the associated morbidity and mortality and the consequences on the patients' quality of life and countries' economies. CKD often evolves without being recognized by patients and physicians, although the diagnosis is based on two simple laboratory data: the estimated glomerular filtration rate (eGFR) and urine analysis. To measure GFR, the knowledge about the physiologic processes at the nephron level, the concept of clearance, and the identification of creatinine as a suitable endogenous marker for measuring the creatinine clearance (CrCl) had to be previously developed. On those bases, different equations to calculate CrCl (Cockcroft and Gault, 1976), or estimated GFR (four variables MDRD, 1999; CKD-Epi, 2009, among others) were generated. They all include creatinine and some demographic data, such as sex and age. However, to compare results throughout life or among laboratories, the creatinine determination must be standardized. In addition, the accuracy of these equations remains controversial in certain subgroups of patients. For these reasons, other mathematical models to improve CrCl estimation have been developed, such as when urine cannot be collected, in debilitated elderly patients and patients with trauma, diabetes, or obesity. Currently, eGFR in adults can be measured and reported immediately, using isotope dilution mass spectrometry traceable creatinine-based equations. In conclusion, based on knowledge obtained from renal physiology, eGFR can be used in the clinic for the diagnosis and early treatment of CKD, as well as a public instrument to estimate the prevalence.

[Triglyceride-glucose product is an independent risk factor for predicting chronic kidney disease in middle-aged and elderly population: a prospective cohort study]

OBJECTIVE

To explore the correlation of triglyceride-glucose product (TyG) index with chronic kidney disease (CKD) in elderly population in Lanzhou (Gansu Province, China).

METHODS

From May to September, 2011, a total of 3868 middleaged and elderly individuals without CKD from 3 communities in Lanzhou were selected as the cohort study population and were followed for an average of 3.1 years (from June, 2014 to August, 2015). After excluding those with missing follow-up data, a total of 3439 individuals were included for analysis, who were divided according to the quartile of TyG index into Q1 group (TyG≤8.47), Q2 group (TyG 8.48-8.84), Q3 group (TyG 8.85-9.20) and Q4 group (TyG>9.20). The estimated glomerular filtration rate (eGFR) and urinary albumin/creatinine ratio (UACR) were used to evaluate the renal function of the participants.

RESULTS

In this cohort, a high TyG index was found to correlate with a high risk of CKD (P < 0.05). Analysis of the follow-up data showed that the TyG index was significantly higher in patients who developed CKD during the follow-up than in those without CKD (P < 0.05). Logistic regression analysis showed that TyG index was an independent risk factor for abnormal eGFR and CKD (P < 0.05).

CONCLUSION

A high TyG index is an independent risk factor for CKD in middle-aged and elderly population.

Kidney disease risk factors do not explain impacts of low dietary protein on kidney function and structure

The kidneys balance many byproducts of the metabolism of dietary components. Previous studies examining dietary effects on kidney health are generally of short duration and manipulate a single macronutrient. Here, kidney function and structure were examined in C57BL/6J mice randomized to consume one of a spectrum of macronutrient combinations (protein [5%–60%], carbohydrate [20%–75%], and fat [20%–75%]) from weaning to late-middle age (15 months). Individual and interactive impacts of macronutrients on kidney health were modeled. Dietary protein had the greatest influence on kidney function, where chronic low protein intake decreased glomerular filtration rates and kidney mass, whereas it increased kidney immune infiltration and structural injury. Kidney outcomes did not align with cardiometabolic risk factors including glucose intolerance, overweight/obesity, dyslipidemia, and hypertension in mice with chronic low protein consumption. This study highlights that protein intake over a lifespan is an important determinant of kidney function independent of cardiometabolic changes.

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Chronic high macronutrient intake from any source increases kidney function (GFR)

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Low protein intake led to greater kidney tubular structural injury and inflammation

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Lower protein intake decreased kidney mass and glomerular filtration capacity

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Kidney outcomes did not align with longevity or cardiometabolic outcomes

CKD: The burden of disease invisible to research funders

The uptake of the current concept of chronic kidney disease (CKD) by the public, physicians and health authorities is low. Physicians still mix up CKD with chronic kidney insufficiency or failure. In a recent manuscript, only 23% of participants in a cohort of persons with CKD had been diagnosed by their physicians as having CKD while 29% has a diagnosis of cancer and 82% had a diagnosis of hypertension. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. A prevalent view is that for those in whom kidneys fail, the problem is “solved” by dialysis or kidney transplantation. However, the main burden of CKD is accelerated aging and all-cause and cardiovascular premature death. CKD is the most prevalent risk factor for lethal COVID-19 and the factor that most increases the risk of death in COVID-19, after old age. Moreover, men and women undergoing KRT still have an annual mortality which is 10–100-fold higher than similar age peers, and life expectancy is shortened by around 40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth global cause of death by 2040 and the second cause of death in Spain before the end of the century, a time when 1 in 4 Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded CIBER network research structure in Spain. Leading Spanish kidney researchers grouped in the kidney collaborative research network REDINREN have now applied for the RICORS call of collaborative research in Spain with the support of the Spanish Society of Nephrology, ALCER and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true. However, only the highest level of research funding through the CIBER will allow to adequately address the issue before it is too late.

The Renal Pathology of Obesity: Structure-Function Correlations

The kidney is one of the target organs that may show health disorders as a result of obesity. Obesity-related glomerulopathy (ORG) is a kidney disease category based on a biopsy diagnosis that may occur secondary to obesity. Detailed clinicopathologic observations of ORG have provided significant knowledge regarding obesity-associated renal complications. Glomerulomegaly with focal segmental glomerulosclerosis of perihilar locations is a typical renal histopathologic finding in ORG, which has long been considered to represent a state of single-nephron glomerular hyperfiltration. This hypothesis was recently confirmed in ORG patients by estimating single-nephron glomerular filtration rate using a combined image analysis and biopsy-based stereology. Overshooting in glomerulotubular and tubuloglomerular interactions may lead to glomerular hyperfiltration/hypertension, podocyte failure, tubular protein-traffic overload, and tubulointerstitial scarring, constituting a vicious cycle of a common pathway to the further loss of functioning nephrons and the progression of kidney functional impairment.

Relationship between Kidney Function and Subclinical Atherosclerosis Progression Evaluated by Coronary Artery Calcification

Aims: The roles of urinary albumin, eGFRcystatin (eGFRcys), and eGFRcreatinine (eGFRcre) in the progression of coronary artery calcification (CAC) remain unclear. Therefore, the present study investigated the relationship between kidney function and CAC progression.

Methods: A total of 760 Japanese men aged 40-79 years were enrolled in this population-based study. Kidney function was measured using eGFRcre, eGFRcys, and the urine albumin-to-creatinine ratio. CAC scores were calculated using the Agatston method. CAC progression was defined as an annual increase of ＞10 Agatston units (AU) among men with 0＜CAC＜100 AU at baseline, that of ＞10% among those with CAC ≥ 100 AU, and any progression for those with CAC=0 at baseline. The relative risk (RR) of CAC progression based on kidney function was assessed using a robust Poisson regression model.

Results: The mean follow-up period was 4.9 years. CAC progression was detected in 45.8% of participants. Positive associations between CAC progression and albuminuria (＞30mg/g) (RR: 1.29; 1.09 to 1.53;p=0.004) and low eGFRcys (＜60ml/min/1.73m²) (RR: 1.27; 1.05 to 1.53;p=0.012) remained significant after adjustments for age, the follow-up time, and computerized tomography type. Following further adjustments for hypertension, diabetes mellitus, dyslipidemia, C-reactive protein, and lifestyle factors, CAC progression was associated with albuminuria (RR: 1.20; 1.01 to 1.43;p=0.04) and low eGFRcys (RR: 1.19; 0.99 to 1.43;p=0.066), but not with eGFRcre.

Conclusion: CAC progression was associated with albuminuria; however, its relationship with eGFRcys was weakened by adjustments for risk factors.

Serum Uric Acid and Kidney Disease Measures Independently Predict Cardiovascular and Total Mortality: The Uric Acid Right for Heart Health (URRAH) Project

Background: Serum uric acid predicts the onset and progression of kidney disease, and the occurrence of cardiovascular and all-cause mortality. Nevertheless, it is unclear which is the appropriate definition of hyperuricemia in presence of chronic kidney disease (CKD). Our goal was to study the independent impact of uric acid and CKD on mortality. Methods: We retrospectively investigated 21,963 patients from the URRAH study database. Hyperuricemia was defined on the basis of outcome specific cut-offs separately identified by ROC curves according to eGFR strata. The primary endpoints were cardiovascular and all-cause mortality. Results: After a mean follow-up of 9.8 year, there were 1,582 (7.20%) cardiovascular events and 3,130 (14.25%) deaths for all causes. The incidence of cardiovascular and all-cause mortality increased in parallel with reduction of eGFR strata and with progressively higher uric acid quartiles. During 215,618 person-years of follow-up, the incidence rate for cardiovascular mortality, stratified based on eGFR (>90, between 60 and 90 and <60 ml/min) was significantly higher in patients with hyperuricemia and albuminuria (3.8, 22.1 and 19.1, respectively) as compared to those with only one risk factor or none (0.4, 2.8 and 3.1, respectively). Serum uric acid and eGFR significantly interact in determining cardiovascular and all-cause mortality. For each SUA increase of 1 mg/dl the risk for mortality increased by 10% even after adjustment for potential confounding factors included eGFR and the presence of albuminuria. Conclusions: hyperuricemia is a risk factor for cardiovascular and all-cause mortality additively to eGFR strata and albuminuria, in patients at cardiovascular risk.

Elevated Levels of Renalase, the β-NAD(P)H Isomerase, Can Be Used as Risk Factors of Major Adverse Cardiovascular Events and All-Cause Death in Patients with Chronic Kidney Disease

Background: Renalase is an enzyme and a cytokine involved in cell survival. Since its discovery, associations between it and both cardiovascular and kidney disease have been noted. Recognizing this, we conducted a study in which we followed patients with chronic kidney disease. Material and methods: The study involved 90 CKD patients with varying stages of the disease and 30 healthy controls. Renalase was measured with an ELISA kit, and patients were followed-up after a median of 18 months. During the follow-up, we asked about the occurrence of MACE, all-cause mortality and the need for dialysis initiation. Results: In CKD subgroups, RNSL correlated with all-cause death only in the HD group (Rs = 0.49, p < 0.01). In the whole CKD population, we found a positive correlation of RNSL concentration and both MACE occurrence (Rs = 0.38, p < 0.001) and all-cause death (Rs = 0.34, p < 0.005). There was a significant increase in MACE occurrence probability in patients with elevated renalase levels (>25 μg/mL). Conclusions: Elevated renalase levels can be used as a risk factor of MACE in patients with CKD, but its long-term utility needs further research. High renalase levels are a risk factor of death among CKD patients. In HD patients, all deaths were observed among patients with >30 μg/mL; this level could be used as a “red flag” marker in future studies.

Anticoagulation in patients with kidney failure on dialysis: factor XI as a therapeutic target

Chronic kidney disease is present in almost 10% of the world population and is associated with excess mortality and morbidity. Reduced glomerular filtration rate and the presence and extent of proteinuria, key domains of chronic kidney disease, have both been shown to be strong and independent risk factors for cardiovascular disease. Patients with kidney failure requiring dialysis are at highest risk for cardiovascular events (e.g., stroke or myocardial infarction), and of developing chronic cardiovascular conditions, such as heart failure. Despite the high burden of cardiovascular disease, there is a paucity of evidence supporting therapies to reduce this risk. Although long-term anticoagulant treatment has the potential to prevent thromboembolism in persons with kidney failure on dialysis, this possibility remains understudied. The limited data available on anticoagulation in patients with kidney failure has focused on vitamin K antagonists or direct oral anticoagulants that inhibit thrombin or factor (F) Xa. The risk of bleeding is a major concern with these agents. However, FXI is emerging as a potential safer target for new anticoagulants because FXI plays a greater part in thrombosis than in hemostasis. In this article, we (i) explain the rationale for considering anticoagulation therapy in patients with kidney failure to reduce atherothrombotic events, (ii) highlight the limitations of current anticoagulants in this patient population, (iii) explain the potential benefits of FXI inhibitors, and (iv) summarize ongoing studies investigating FXI inhibition in patients with kidney failure on dialysis.

Urine Albumin-Creatinine ratio is associated with prognosis in patients with diabetic foot osteomyelitis

AIMS

We aimed to explore the association between albuminuria and clinical outcomes in patients with diabetic foot osteomyelitis (DFO).

METHODS

This is an observational retrospective study and a total of 202 inpatients with DFO were eligible for inclusion in our study. Based on urine albumin-creatinine ratio (UACR), the patients were divided into three groups: normoalbuminuria group, microalbuminuria group and macroalbuminuria group. The data collected include demographics data, laboratory data, clinical diagnostic data, diabetic foot examination and clinical visit data. The association was then evaluated between albuminuria and all-cause mortality, major cardiovascular adverse events (MACE) and mixed endpoint events.

RESULTS

The mean age was 60.3 years, 62.9% were male and 45.05% were urinary protein-positive. The incidence rates of all-cause mortality, MACE and mixed endpoint events related to elevated UACR were significantly increased in patients with DFO (all P for trend < 0.01). After adjusting for confounders, compared with normoalbuminuria group, the risk of all-cause mortality, MACE and mixed endpoint events in the microalbuminuria group increased by 81.8%, 135.4% and 136.4%, respectively. The risk of all-cause mortality, MACE and mixed endpoint events in the macroalbuminuria group increased by 246.2%, 145.1% and 252.3%, respectively. The population attributable risk percentage (PAR%) suggested that 50.16% of all-cause mortality, 47.85% of MACE and 59.11% of mixed endpoint events could be attributed to the elevated UACR. Meanwhile, compared with normoalbuminuria, those with microalbuminuria or macroalbuminuria have lower apoA1 and ABI, higher SCr and higher incidence rate of CHD, hindfoot infection and severe infection (all P < 0.05).

CONCLUSIONS

In patients with DFO, the UACR level is associated with all-cause mortality, MACE and mixed endpoint events and elevated UACR levels increase the risk of all-cause mortality, MACE and mixed endpoint events.

Association of Kidney Function With NMR-Quantified Lipids, Lipoproteins, and Metabolic Measures in Mexican Adults

CONTEXT

Chronic kidney disease (CKD) and diabetes are associated with dyslipidemia, metabolic abnormalities, and atherosclerotic risk. Nuclear magnetic resonance (NMR) spectroscopy provides much more detail on lipoproteins than traditional assays.

METHODS

In about 38 000 participants from the Mexico City Prospective Study, aged 35 to 84 years and not using lipid-lowering medication, NMR spectroscopy quantified plasma concentrations of lipoprotein particles, their lipidic compositions, and other metabolic measures. Linear regression related low estimated glomerular filtration rate (eGFR; <60 mL/min/1.73 m2) to each NMR measure after adjustment for confounders and for multiplicity. Analyses were done separately for those with and without diabetes.

RESULTS

Among the 38 081 participants (mean age 52 years, 64% women), low eGFR was present for 4.8% (306/6403) of those with diabetes and 1.2% (365/31 678) of those without diabetes. Among both those with and without diabetes, low eGFR was significantly associated with higher levels of 58 NMR measures, including apolipoprotein B (Apo-B), the particle numbers of most Apo-B containing lipoproteins, the cholesterol and triglycerides carried in these lipoproteins, several fatty acids, total cholines and phosphatidylcholine, citrate, glutamine, phenylalanine, β-OH-butyrate, and the inflammatory measure glycoprotein-A, and significantly lower levels of 13 NMR measures, including medium and small high-density lipoprotein particle measures, very low-density lipoprotein particle size, the ratio of saturated:total fatty acids, valine, tyrosine, and aceto-acetate.

CONCLUSIONS

In this Mexican population with high levels of adiposity and diabetes, low kidney function was associated with widespread alterations in lipidic and metabolic profiles, both in those with and without diabetes. These alterations may help explain the higher atherosclerotic risk experienced by people with CKD.

Chronic kidney disease measures for cardiovascular risk prediction

Chronic kidney disease (CKD) affects 15-20% of adults globally and causes various complications, one of the most important being cardiovascular disease (CVD). CKD has been associated with many CVD subtypes, especially severe ones like heart failure, independent of potential confounders such as diabetes and hypertension. There is no consensus in major clinical guidelines as to how to incorporate the two key measures of CKD (glomerular filtration rate and albuminuria) for CVD risk prediction. This is a critical missed opportunity to appropriately refine predicted risk and personalize prevention therapies according to CKD status, particularly since these measures are often already evaluated in clinical care. In this review, we provide an overview of CKD definition and staging, the subtypes of CVD most associated with CKD, major pathophysiological mechanisms, and the current state of CKD as a predictor of CVD in major clinical guidelines. We will introduce the novel concept of a "CKD Add-on", which allows the incorporation of CKD measures in existing risk prediction models, and the implications of taking into account CKD in the management of CVD risk.

RICORS2040: the need for collaborative research in chronic kidney disease

Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is ‘solved’ by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020–2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true.

Association between renal function and cardiovascular mortality: a retrospective cohort study of elderly from health check-up

OBJECTIVES

This study aimed to investigate the relationship between cardiovascular mortality in elderly Asians and decline in renal function.

DESIGN

A retrospective cohort study.

SETTING

Community-based health examination database from Taipei city.

PARTICIPANTS

At the beginning, the database included 315 045 health check-up visits of 97 803 elderly persons aged ≥65 years old from 2005 to 2012. After excluding missing values and outliers, there were 64 732 elderly persons with at least two visits retained for further analyses.

PRIMARY OUTCOME MEASURES

Kidney function indicators include estimated glomerular filtration rate (eGFR) and urine protein, and rapid decline in eGFR was defined as slope ≤ -5 mL/min/1.73 m² per year. The endpoint outcome was defined as the cardiovascular deaths registered in the death registry encoded by the International Classification of Diseases. We applied a Cox proportional hazards model to analyse the association between renal function and cardiovascular mortality.

RESULTS

In this study, we found 1264 elderly persons died from cardiovascular diseases, for whom the data included 4055 previous health check-up visits. We observed significant and independent associations of eGFR <60 mL/min/1.73 m² (HR (95% CI) of 60>eGFR≥45 and eGFR<45 in males: 2.85 (1.33 to 6.09) and 3.98 (1.84 to 8.61); in females: 3.66 (1.32 to 10.15) and 6.77 (2.41 to 18.99)), positive proteinuria (HR (95% CI) of +/-, +,++ and +++, ++++ in males: 1.51 (1.29 to 1.78) and 2.31 (1.51 to 3.53); in females: 1.93 (1.54 to 2.42) and 4.23 (2.34 to 7.65)) and rapid decline in eGFR (HR (95% CI) in males: 3.24 (2.73 to 3.85); in females: 2.83 (2.20 to 3.64) with higher risk of cardiovascular mortality. The joint effect of increased concentration of urine protein and reduced eGFR was associated with a higher risk of cardiovascular mortality.

CONCLUSIONS

Renal function and rapid decline in renal function are independent risk factors for cardiovascular mortality in the elderly.

Systematic Review of Cardiovascular Outcome Trials Using New Antidiabetic Agents in CKD Stratified by Estimated GFR

Introduction

Cardiovascular benefits observed with new antidiabetic agents may not extend to chronic kidney disease (CKD) patients. This study performed a systematic review and meta-analysis of cardiovascular outcome trials (CVOTs) using new antidiabetic agents stratified by kidney function.

Methods

MEDLINE (via PubMed) and the Cochrane Central Register of Controlled Trials were searched for eligible studies up to November 16, 2020. Data were stratified by the trial entry estimated glomerular filtration rate (eGFR) and albuminuria. Primary major cardiovascular event (MACE) outcomes were extracted, and a meta-analysis with a random effects model was performed to estimate overall risk ratios (RRs).

Results

Our search identified 16 studies for inclusion (glucagon-like peptide-1 [GLP-1] analogues, n = 6; dipeptidyl-peptidase 4 [DPP-4] inhibitors, n = 4; and sodium-glucose cotransporter-2 [SGLT-2] inhibitors, n = 6) with a combined total of 150,816 participants (28.2% with eGFR <60 ml/min per 1.73 m², n = 42,534). The RR for MACE with GLP-1 analogues with an eGFR ≥60 ml/min per 1.73 m² was 0.87 (95% confidence interval [CI], 0.77-0.98; P = 0.02) and 0.90 (95% CI, 0.78-1.04; P = 0.14) with an eGFR <60 ml/min per 1.73 m². The RR for MACE with DPP-4 inhibitors with eGFR ≥60 ml/min per 1.73 m² was 0.99 (95% CI, 0.92-1.07; P = 0.86) and 0.99 (95% CI, 0.91-1.08; P = 0.86) with an eGFR <60 ml/min per 1.73 m². The RR for MACE with SGLT-2 inhibitors with an eGFR ≥60 ml/min per 1.73 m² was 1.01 (95% CI, 0.92-1.10; P = 0.87) and 0.85 (95% CI, 0.75-0.95; P = 0.005) with an eGFR <60 ml/min per 1.73 m². Most analyses had significant heterogeneity. Sufficient albuminuria data were unavailable to analyze empirically.

Conclusion

Clear evidence for MACE prevention in diabetes patients with an eGFR <60 ml/min per 1.73 m² currently exists for SGLT-2 inhibitors only. However, similar GLP-1 analogue effect sizes suggest a lack of sufficient power rather than a lack of effect.

Cardiovascular and Renal Outcomes with Efpeglenatide in Type 2 Diabetes

BACKGROUND

Four glucagon-like peptide-1 (GLP-1) receptor agonists that are structurally similar to human GLP-1 have been shown to reduce the risk of adverse cardiovascular events among persons with type 2 diabetes. The effect of an exendin-based GLP-1 receptor agonist, efpeglenatide, on cardiovascular and renal outcomes in patients with type 2 diabetes who are also at high risk for adverse cardiovascular events is uncertain.

METHODS

In this randomized, placebo-controlled trial conducted at 344 sites across 28 countries, we evaluated efpeglenatide in participants with type 2 diabetes and either a history of cardiovascular disease or current kidney disease (defined as an estimated glomerular filtration rate of 25.0 to 59.9 ml per minute per 1.73 m² of body-surface area) plus at least one other cardiovascular risk factor. Participants were randomly assigned in a 1:1:1 ratio to receive weekly subcutaneous injections of efpeglenatide at a dose of 4 or 6 mg or placebo. Randomization was stratified according to use of sodium-glucose cotransporter 2 inhibitors. The primary outcome was the first major adverse cardiovascular event (MACE; a composite of nonfatal myocardial infarction, nonfatal stroke, or death from cardiovascular or undetermined causes).

RESULTS

A total of 4076 participants were enrolled; 2717 were assigned to receive efpeglenatide and 1359 to receive placebo. During a median follow-up of 1.81 years, an incident MACE occurred in 189 participants (7.0%) assigned to receive efpeglenatide (3.9 events per 100 person-years) and 125 participants (9.2%) assigned to receive placebo (5.3 events per 100 person-years) (hazard ratio, 0.73; 95% confidence interval [CI], 0.58 to 0.92; P<0.001 for noninferiority; P = 0.007 for superiority). A composite renal outcome event (a decrease in kidney function or macroalbuminuria) occurred in 353 participants (13.0%) assigned to receive efpeglenatide and in 250 participants (18.4%) assigned to receive placebo (hazard ratio, 0.68; 95% CI, 0.57 to 0.79; P<0.001). Diarrhea, constipation, nausea, vomiting, or bloating occurred more frequently with efpeglenatide than with placebo.

CONCLUSIONS

In this trial involving participants with type 2 diabetes who had either a history of cardiovascular disease or current kidney disease plus at least one other cardiovascular risk factor, the risk of cardiovascular events was lower among those who received weekly subcutaneous injections of efpeglenatide at a dose of 4 or 6 mg than among those who received placebo. (Funded by Sanofi; AMPLITUDE-O ClinicalTrials.gov number, NCT03496298.).

A Cross-Sectional Study for Prevalence and Association of Risk Factors of Chronic Kidney Disease Among People With Type 2 Diabetes in the Indian Setting

INTRODUCTION

Current evidence demonstrates that people with type 2 diabetes (T2D) are at a higher risk of developing chronic kidney disease (CKD) with greater morbidity and mortality. We, therefore, aimed to document and categorize demographic, anthropometric, and physiological risk factors of CKD in people with T2D in India. Additionally, we also attempted to evaluate the magnitude of each risk factor, namely age, duration of diabetes, HbA1c, and body mass index (BMI) in its etiology.

METHODS

This observational, single-center, and cross-sectional study was performed at a diabetes care center in Lucknow, India. Out of a total of 504 eligible patients, we could get the required data from 435 patients. The following data were collected: demographic data, estimated glomerular filtration rate (eGFR), serum creatinine, urinary albumin creatinine ratio (UACR), and HbA1c levels. Appropriate statistical tests were applied.

RESULT

The 435 eligible people with diabetes had a mean age (SD) of 51 (±10.52) years; female 48.02%, duration of diabetes 7 (±5.4) years; HbA1c 8.6 (±2.3)% and eGFR values 80.2 (±26.6) mL/min/1.73m2 at the time of presentation. The eGFR values correlated negatively with age and duration of diabetes, and positively with increasing BMI. The Spearman correlation coefficient showed that clinical parameters such as age, duration of diabetes, and BMI have a weak, but statistically significant correlation with eGFR while eGFR did not correlate with HbA1c level in the study. Further, we did not find a correlation between eGFR and UACR.

CONCLUSION

In people with T2D, age and duration of diabetes are important risk factors for the development of CKD based on the eGFR. Hence, even in the absence of high UACR values, a low eGFR should prompt periodic monitoring to reduce the risk of progression of CKD, especially, in older people with long-standing T2D. Our study did not find HbA1c as a suitable tool to assess the CKD progression risk, but historical glycaemic control over longer periods revealed by sequential values of HbA1c over the duration of disease may correlate with the progression of CKD.

Changes in GFR and Albuminuria in Routine Clinical Practice and the Risk of Kidney Disease Progression

RATIONALE & OBJECTIVE

Changes in urinary albumin-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) have been used separately as alternative kidney disease outcomes in randomized trials. We tested the hypothesis that combined changes in UACR and eGFR predict advanced kidney disease better than either alone.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

91,319 primary care patients assembled from the Clinical Practice Research Datalink in the United Kingdom between 2000 and 2015.

EXPOSURES

Changes in UACR and eGFR (categorized as ≥30% increase, stable, or ≥30% decrease), alone and in combination, over a 3-year period.

OUTCOMES

The primary outcome was advanced CKD (sustained eGFR <30 mL/min/1.73 m2); secondary outcomes included kidney failure, cardiovascular disease, and all-cause mortality.

ANALYTICAL APPROACH

Multivariable Cox regression with bias from missing values assessed using multiple imputation; discrimination statistics compared across exposure groups.

RESULTS

91,319 individuals were studied, with a mean eGFR of 72.6 mL/min/1.73 m2 and median UACR of 9.7 mg/g; 70,957 (77.7%) had diabetes. During a median follow-up of 2.9 years, 2,541 people progressed to advanced CKD. Compared with stable values, hazard ratios for a ≥30% increase in UACR and ≥30% decrease in eGFR were 1.78 (95% CI, 1.59-1.98) and 7.53 (95% CI, 6.70-8.45), respectively, for the outcome of advanced CKD. Compared with stable values of both, the hazard ratio for the combination of an increase in UACR and a decrease in eGFR was 15.15 (95% CI, 12.43-18.46) for the outcome of advanced CKD. The combination of changes in UACR and eGFR predicted kidney outcomes better than either alone.

LIMITATIONS

Selection bias, relatively small proportion of individuals without diabetes, and very few kidney failure events.

CONCLUSIONS

In a large-scale general population, the combination of an increase in UACR and a decrease in eGFR was strongly associated with the risk of advanced CKD. Further assessment of combined changes in UACR and eGFR as an alternative outcome for kidney failure in trials of CKD progression is warranted.

Management of Blood Pressure in Patients With Chronic Kidney Disease Not Receiving Dialysis: Synopsis of the 2021 KDIGO Clinical Practice Guideline

DESCRIPTION

The Kidney Disease: Improving Global Outcomes (KDIGO) 2021 clinical practice guideline for the management of blood pressure (BP) in patients with chronic kidney disease (CKD) not receiving dialysis is an update of the KDIGO 2012 guideline on the same topic and reflects new evidence on the risks and benefits of BP-lowering therapy among patients with CKD. It is intended to support shared decision making by health care professionals working with patients with CKD worldwide. This article is a synopsis of the full guideline.

METHODS

The KDIGO leadership commissioned 2 co-chairs to convene an international Work Group of researchers and clinicians. After a Controversies Conference in September 2017, the Work Group defined the scope of the evidence review, which was undertaken by an evidence review team between October 2017 and April 2020. Evidence reviews were done according to the Cochrane Handbook. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach was used to guide the development of the recommendations and rate the strength and quality of the evidence. Practice points were included to provide guidance when evidence was insufficient to make a graded recommendation. The guideline was revised after public consultation between January and March 2020.

RECOMMENDATIONS

The updated guideline comprises 11 recommendations and 20 practice points. This synopsis summarizes key recommendations pertinent to the diagnosis and management of high BP in adults with CKD, excluding those receiving kidney replacement therapy. In particular, the synopsis focuses on recommendations for standardized BP measurement and a target systolic BP of less than 120 mm Hg, because these recommendations differ from some other guidelines.

Chronic kidney disease

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

Ticagrelor monotherapy in patients with chronic kidney disease undergoing percutaneous coronary intervention: TWILIGHT-CKD

AIMS

The aim of this study was to assess the impact of chronic kidney disease (CKD) on the safety and efficacy of ticagrelor monotherapy among patients undergoing percutaneous coronary intervention (PCI).

METHODS AND RESULTS

In this prespecified subanalysis of the TWILIGHT trial, we evaluated the treatment effects of ticagrelor with or without aspirin according to renal function. The trial enrolled patients undergoing drug-eluting stent implantation who fulfilled at least one clinical and one angiographic high-risk criterion. Chronic kidney disease, defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, was a clinical study entry criterion. Following a 3-month period of ticagrelor plus aspirin, event-free patients were randomly assigned to aspirin or placebo on top of ticagrelor for an additional 12 months. Of the 6835 patients randomized and with available eGFR at baseline, 1111 (16.3%) had CKD. Ticagrelor plus placebo reduced the primary endpoint of Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding as compared with ticagrelor plus aspirin in both patients with [4.6% vs. 9.0%; hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.31-0.80] and without (4.0% vs. 6.7%; HR 0.59, 95% CI 0.47-0.75; Pinteraction = 0.508) CKD, but the absolute risk reduction was greater in the former group. Rates of death, myocardial infarction, or stroke were not significantly different between the two randomized groups irrespective of the presence (7.9% vs. 5.7%; HR 1.40, 95% CI 0.88-2.22) or absence of (3.2% vs. 3.6%; HR 0.90, 95% CI 0.68-1.20; Pinteraction = 0.111) CKD.

CONCLUSION

Among CKD patients undergoing PCI, ticagrelor monotherapy reduced the risk of bleeding without a significant increase in ischaemic events as compared with ticagrelor plus aspirin.

Long-term monitoring in primary care for chronic kidney disease and chronic heart failure: a multi-method research programme

Background

Long-term monitoring is important in chronic condition management. Despite considerable costs of monitoring, there is no or poor evidence on how, what and when to monitor. The aim of this study was to improve understanding, methods, evidence base and practice of clinical monitoring in primary care, focusing on two areas: chronic kidney disease and chronic heart failure.

Objectives

The research questions were as follows: does the choice of test affect better care while being affordable to the NHS? Can the number of tests used to manage individuals with early-stage kidney disease, and hence the costs, be reduced? Is it possible to monitor heart failure using a simple blood test? Can this be done using a rapid test in a general practitioner consultation? Would changes in the management of these conditions be acceptable to patients and carers?

Design

Various study designs were employed, including cohort, feasibility study, Clinical Practice Research Datalink analysis, seven systematic reviews, two qualitative studies, one cost-effectiveness analysis and one cost recommendation.

Setting

This study was set in UK primary care.

Data sources

Data were collected from study participants and sourced from UK general practice and hospital electronic health records, and worldwide literature.

Participants

The participants were NHS patients (Clinical Practice Research Datalink: 4.5 million patients), chronic kidney disease and chronic heart failure patients managed in primary care (including 750 participants in the cohort study) and primary care health professionals.

Interventions

The interventions were monitoring with blood and urine tests (for chronic kidney disease) and monitoring with blood tests and weight measurement (for chronic heart failure).

Main outcome measures

The main outcomes were the frequency, accuracy, utility, acceptability, costs and cost-effectiveness of monitoring.

Results

Chronic kidney disease: serum creatinine testing has increased steadily since 1997, with most results being normal (83% in 2013). Increases in tests of creatinine and proteinuria correspond to their introduction as indicators in the Quality and Outcomes Framework. The Chronic Kidney Disease Epidemiology Collaboration equation had 2.7% greater accuracy (95% confidence interval 1.6% to 3.8%) than the Modification of Diet in Renal Disease equation for estimating glomerular filtration rate. Estimated annual transition rates to the next chronic kidney disease stage are ≈ 2% for people with normal urine albumin, 3–5% for people with microalbuminuria (3–30 mg/mmol) and 3–12% for people with macroalbuminuria (> 30 mg/mmol). Variability in estimated glomerular filtration rate-creatinine leads to misclassification of chronic kidney disease stage in 12–15% of tests in primary care. Glycaemic-control and lipid-modifying drugs are associated with a 6% (95% confidence interval 2% to 10%) and 4% (95% confidence interval 0% to 8%) improvement in renal function, respectively. Neither estimated glomerular filtration rate-creatinine nor estimated glomerular filtration rate-Cystatin C have utility in predicting rate of kidney function change. Patients viewed phrases such as ‘kidney damage’ or ‘kidney failure’ as frightening, and the term ‘chronic’ was misinterpreted as serious. Diagnosis of asymptomatic conditions (chronic kidney disease) was difficult to understand, and primary care professionals often did not use ‘chronic kidney disease’ when managing patients at early stages. General practitioners relied on Clinical Commissioning Group or Quality and Outcomes Framework alerts rather than National Institute for Health and Care Excellence guidance for information. Cost-effectiveness modelling did not demonstrate a tangible benefit of monitoring kidney function to guide preventative treatments, except for individuals with an estimated glomerular filtration rate of 60–90 ml/minute/1.73 m2, aged < 70 years and without cardiovascular disease, where monitoring every 3–4 years to guide cardiovascular prevention may be cost-effective. Chronic heart failure: natriuretic peptide-guided treatment could reduce all-cause mortality by 13% and heart failure admission by 20%. Implementing natriuretic peptide-guided treatment is likely to require predefined protocols, stringent natriuretic peptide targets, relative targets and being located in a specialist heart failure setting. Remote monitoring can reduce all-cause mortality and heart failure hospitalisation, and could improve quality of life. Diagnostic accuracy of point-of-care N-terminal prohormone of B-type natriuretic peptide (sensitivity, 0.99; specificity, 0.60) was better than point-of-care B-type natriuretic peptide (sensitivity, 0.95; specificity, 0.57). Within-person variation estimates for B-type natriuretic peptide and weight were as follows: coefficient of variation, 46% and coefficient of variation, 1.2%, respectively. Point-of-care N-terminal prohormone of B-type natriuretic peptide within-person variability over 12 months was 881 pg/ml (95% confidence interval 380 to 1382 pg/ml), whereas between-person variability was 1972 pg/ml (95% confidence interval 1525 to 2791 pg/ml). For individuals, monitoring provided reassurance; future changes, such as increased testing, would be acceptable. Point-of-care testing in general practice surgeries was perceived positively, reducing waiting time and anxiety. Community heart failure nurses had greater knowledge of National Institute for Health and Care Excellence guidance than general practitioners and practice nurses. Health-care professionals believed that the cost of natriuretic peptide tests in routine monitoring would outweigh potential benefits. The review of cost-effectiveness studies suggests that natriuretic peptide-guided treatment is cost-effective in specialist settings, but with no evidence for its value in primary care settings.

Limitations

No randomised controlled trial evidence was generated. The pathways to the benefit of monitoring chronic kidney disease were unclear.

Conclusions

It is difficult to ascribe quantifiable benefits to monitoring chronic kidney disease, because monitoring is unlikely to change treatment, especially in chronic kidney disease stages G3 and G4. New approaches to monitoring chronic heart failure, such as point-of-care natriuretic peptide tests in general practice, show promise if high within-test variability can be overcome.

Future work

The following future work is recommended: improve general practitioner–patient communication of early-stage renal function decline, and identify strategies to reduce the variability of natriuretic peptide.

Study registration

This study is registered as PROSPERO CRD42015017501, CRD42019134922 and CRD42016046902.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 10. See the NIHR Journals Library website for further project information.

Association between Inguinal Hernia and Arterial Disease: A Preliminary Report

Simple Summary

While the association between venous disease and inguinal hernia has been well demonstrated, there is less evidence concerning the association between arterial diseases (AD), such as carotid stenosis, peripheral artery disease and abdominal aortic aneurysms, and inguinal hernia. We surprisingly found that the prevalence of AD is large, being higher than 40% in our study cohort. Moreover, patients with AD as compared to those without AD are characterized by additional other comorbidities such as greater albuminuria, higher frequency of a smoking habit and older age. Hence, we provided a characterization of patients with inguinal hernia with respect to concomitant presence of AD.

Abstract

Background: Inguinal hernia (IH) is a major problem in general surgery and its prevalence is increasing. The presence of hernias has been associated with a wide spectrum of venous diseases, with the involvement of imbalances in collagen and extracellular matrix deposition and metalloproteinases dysfunction. We aimed to evaluate whether the association between IH and vascular diseases is also present with respect to arterial diseases. Methods: We designed a cross-sectional observational study enrolling consecutive patients undergoing surgical repair of IH. Arterial diseases (AD) considered were carotid stenosis, peripheral artery disease and abdominal aortic aneurysms. Results: Study population consisted of 70 patients. Mean age was 63.2 ± 4.7 years. Prevalence of AD was 42.9% in the whole cohort. AD patients were older (p = 0.015), and more frequently had hypertension (p = 0.001) and active smoking habits (p = 0.001) than the no-AD group. Albumin-to-creatinine ratio (ACR) was higher in AD than in no-AD patients (p < 0.001). At multivariable analysis, increased ACR (odds ratio, OR: 1.14, p < 0.001), old age (OR: 1.25, p = 0.001) and a smoking habit (OR: 3.20, p = 0.001) were significant correlates for the presence of AD. Conclusions: Prevalence of AD in patients with IH is non-negligible. Old age, a smoking habit and an abnormal excretion of urine albumin are associated with the presence of AD in these patients. Future studies are needed to gain more insights into the pathogenic mechanisms underlying this association, exploring also the specific role of metalloproteinases.

Kidney-Related Research in the United States: A Position Statement From the National Kidney Foundation and the American Society of Nephrology

Kidney disease is an important US public health problem because it affects over 37 million Americans, and Medicare expenditures for patients with chronic kidney disease now alone exceed $130 billion annually. Kidney disease is characterized by strong racial, ethnic, and socioeconomic disparities, and reducing kidney disease incidence will positively impact US health disparities. Due to the aging of the US population and an unabated obesity epidemic, the number of patients receiving treatment for kidney failure is anticipated to increase, which will escalate kidney disease health expenditures. The historical and current investment in kidney-related research via the National Institute of Diabetes and Digestive and Kidney Diseases has severely lagged behind ongoing expenditures for kidney disease care. Increasing research investment will identify, develop, and increase implementation of interventions to slow kidney disease progression, reduce incidence of kidney failure, enhance survival, and improve quality of life. This perspective states the urgent reasons why increasing investment in kidney-related research is important for US public health. The National Kidney Foundation and the American Society of Nephrology are working together to advocate for increased funding for the National Institute of Diabetes and Digestive and Kidney Diseases. The long-term goal is to reduce the burden of kidney disease in the US population and improve the quality of life of patients living with kidney disease.