Prediction of the risk of 3-year chronic kidney disease among elderly people: a community-based cohort study

OBJECTIVE

We conducted a community-based cohort study to predict the 3-year occurrence of chronic kidney disease (CKD) among population aged ≥60 years.

METHOD

Participants were selected from two communities through randomized cluster sampling in Jiading District of Shanghai, China. The two communities were randomly divided into a development cohort (n = 12012) and a validation cohort (n = 6248) with a 3-year follow-up. Logistic regression analysis was used to determine the independent predictors. A nomogram was established to predict the occurrence of CKD within 3 years. The area under the curve (AUC), the calibration curve and decision curve analysis (DCA) curve were used to evaluate the model.

RESULT

At baseline, participants in development cohort and validation cohort were with the mean age of 68.24 ± 5.87 and 67.68 ± 5.26 years old, respectively. During 3 years, 1516 (12.6%) and 544 (8.9%) new cases developed CKD in the development and validation cohorts, respectively. Nine variables (age, systolic blood pressure, body mass index, exercise, previous hypertension, triglycerides, fasting plasma glucose, glycated hemoglobin and serum creatinine) were included in the prediction model. The AUC value was 0.742 [95% confidence interval (CI), 0.728-0.756] in the development cohort and 0.881(95%CI, 0.867-0.895) in the validation cohort, respectively. The calibration curves and DCA curves demonstrate an effective predictive model.

CONCLUSION

Our nomogram model is a simple, reasonable and reliable tool for predicting the risk of 3-year CKD in community-dwelling elderly people, which is helpful for timely intervention and reducing the incidence of CKD.

Prevalence and risk factors for impaired renal function among Asian patients with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is associated with impaired renal function, and both diseases often occur alongside other metabolic disorders. However, the prevalence and risk factors for impaired renal function in patients with NAFLD remain unclear. The objective of this study was to identify the prevalence and risk factors for renal impairment in NAFLD patients.

METHODS

All adults aged 18-70 years with ultrasound-diagnosed NAFLD and transient elastography examination from eight Asian centers were enrolled in this prospective study. Liver fibrosis and cirrhosis were assessed by FibroScan-aspartate aminotransferase (FAST), Agile 3+ and Agile 4 scores. Impaired renal function and chronic kidney disease (CKD) were defined by an estimated glomerular filtration rate (eGFR) with value of < 90 mL/min/1.73 m2 and < 60 mL/min/1.73 m2, respectively, as estimated by the CKD-Epidemiology Collaboration (CKD-EPI) equation.

RESULTS

Among 529 included NAFLD patients, the prevalence rates of impaired renal function and CKD were 37.4% and 4.9%, respectively. In multivariate analysis, a moderate-high risk of advanced liver fibrosis and cirrhosis according to Agile 3+ and Agile 4 scores were independent risk factors for CKD (P< 0.05). Furthermore, increased fasting plasma glucose (FPG) and blood pressure were significantly associated with impaired renal function after controlling for the other components of metabolic syndrome (P< 0.05). Compared with patients with normoglycemia, those with prediabetes [FPG ≥ 5.6 mmol/L or hemoglobin A1c (HbA1c) ≥ 5.7%] were more likely to have impaired renal function (P< 0.05).

CONCLUSIONS

Agile 3+ and Agile 4 are reliable for identifying NAFLD patients with high risk of CKD. Early glycemic control in the prediabetic stage might have a potential renoprotective role in these patients.

Temporal validation of a Generalized Additive2 Model (GA2M) to assess the risk of Chronic Kidney Disease (CKD)

OBJECTIVE

To assess the temporal validity of a model predicting the risk of Chronic Kidney Disease (CKD) using Generalized Additive2 Models (GA2M).

MATERIALS

We adopted the Italian Health Search Database (HSD) with which the original algorithm was developed and validated by comparing different machine learnings models.

METHODS

We selected all patients aged >=15 being active in HSD in 2019. They were followed up until December 2022 so being updated with three years of data collection. Those with prior diagnosis of CKD were excluded. A GA2M-based algorithm for CKD prediction was applied to this cohort in order to compare observed and predicted risk. Area Under Curve (AUC) and Average Precision (AP) were calculated.

RESULTS

We obtained an AUC and AP equal to 88% and 30%, respectively.

DISCUSSION

The prediction accuracy of the algorithm was largely consistent with that obtained in our prior work which was based on a different time-window for data collection. We therefore underlined and demonstrated the relevance of temporal validation for this prediction tool.

CONCLUSION

The GA2M confirmed its high accuracy in prediction of CKD. As such, the respective patient- and population-based informatic tools might be implemented in primary care.

Screening for protein energy wasting in children with chronic kidney disease using dual energy x-ray absorptiometry as an additional tool

BACKGROUND

The current diagnosis of protein energy wasting (PEW) is based on scoring systems that lack precision in measuring muscle deficits. We undertook this cross-sectional study to determine the prevalence of PEW in children with chronic kidney disease (CKD) using a scoring system that included dual energy x-ray absorptiometry (DEXA) for measuring lean body mass (LBM) and to determine the prevalence of selected markers in PEW.

METHODS

Thirty CKD and 20 healthy children (1-18 years) were evaluated for (1) reduced dietary protein intake (DPI); (2) BMI < fifth centile for height age (BMI/HA); (3) serum albumin < 3.8 g/dl, cholesterol < 100 mg/dl, or CRP > 3 mg/L; (4) LBM < fifth centile for height age [LBMr] on DEXA. PEW was scored as minimal-one parameter positive in 2/4 categories; standard-one parameter positive in 3/4 categories; or modified-standard plus height < 2 SD.

RESULTS

Twenty children with CKD (66.7%) had PEW, (5/9) 55% in CKD 3, and (15/21) 71% in advanced CKD; minimal 12, standard 1, and modified 7. LBMr was seen in 20 (100%), reduced DPI in 16 (80%), and BMI/HA in 6 (30%) children with PEW. LBMr had 100% sensitivity and BMI/HA 100% specificity. LBMr was seen in 8 who had no other criteria for PEW. None of the parameters were positive in controls (p < 0.01).

CONCLUSIONS

PEW prevalence in CKD was high. Both prevalence and severity were higher in advanced CKD. LBMr was a highly sensitive marker to detect PEW. LBMr seen in some children with CKD who were negative for other markers could represent subclinical PEW.

Reassuring pregnancy outcomes in women with mild COL4A3-5-related disease (Alport syndrome) and genetic type of disease can aid personalized counseling

Individualized pre-pregnancy counseling and antenatal care for women with chronic kidney disease (CKD) require disease-specific data. Here, we investigated pregnancy outcomes and long-term kidney function in women with COL4A3-5 related disease (Alport Syndrome, (AS)) in a large multicenter cohort. The ALPART-network (mAternaL and fetal PregnAncy outcomes of women with AlpoRT syndrome), an international collaboration of 17 centers, retrospectively investigated COL4A3-5 related disease pregnancies after the 20th week. Outcomes were stratified per inheritance pattern (X-Linked AS (XLAS)), Autosomal Dominant AS (ADAS), or Autosomal Recessive AS (ARAS)). The influence of pregnancy on estimated glomerular filtration rate (eGFR)-slope was assessed in 192 pregnancies encompassing 116 women (121 with XLAS, 47 with ADAS, and 12 with ARAS). Median eGFR pre-pregnancy was over 90ml/min/1.73m2. Neonatal outcomes were favorable: 100% live births, median gestational age 39.0 weeks and mean birth weight 3135 grams. Gestational hypertension occurred during 23% of pregnancies (reference: 'general' CKD G1-G2 pregnancies incidence is 4-20%) and preeclampsia in 20%. The mean eGFR declined after pregnancy but remained within normal range (over 90ml/min/1.73m2). Pregnancy did not significantly affect eGFR-slope (pre-pregnancy β=-1.030, post-pregnancy β=-1.349). ARAS-pregnancies demonstrated less favorable outcomes (early preterm birth incidence 3/11 (27%)). ARAS was a significant independent predictor for lower birth weight and shorter duration of pregnancy, next to the classic predictors (pre-pregnancy kidney function, proteinuria, and chronic hypertension) though missing proteinuria values and the small ARAS-sample hindered analysis. This is the largest study to date on AS and pregnancy with reassuring results for mild AS, though inheritance patterns could be considered in counseling next to classic risk factors. Thus, our findings support personalized reproductive care and highlight the importance of investigating kidney disease-specific pregnancy outcomes.

Cystatin C should be routinely available for estimating kidney function

PURPOSE OF REVIEW

In this report, we summarize why the availability of cystatin C is important across a variety of clinical scenarios, the recent literature on when, why and in whom cystatin C testing should be considered, and how nephrologists can take practical steps to incorporate cystatin C testing into their practice.

RECENT FINDINGS

Large intra-individual discrepancies between estimated glomerular filtration rate by creatinine (eGFRcr) and estimated glomerular filtration rate by creatinine eGFRcys (known as eGFRdiff) are observed in at least 1 in 4 people. These differences are seen more commonly among more vulnerable individuals: older adults, females, non-White individuals and those living with multiple medical conditions. A large eGFRdiff, where eGFRcys is lower than eGFRcr, is associated with a plethora of adverse outcomes, including medication-associated adverse events, acute kidney injury, cardiovascular disease, kidney failure and all-cause mortality. Among studies that have measured GFR, eGFRcr-cys usually provides the most accurate estimation of kidney function compared to mGFR, including among participants with large discrepancies between eGFRcr and eGFRcys.

SUMMARY

Cystatin C improves sensitivity and specificity of chronic kidney disease diagnosis, improves detection of harmful acute and chronic changes in kidney function, improves precision of treatment eligibility and safety, and may reduce healthcare inequalities. Better education, curiosity, and motivation among nephrologists could substantially improve the availability and utilization of cystatin C.

Novel indications for referral and care for simultaneous liver kidney transplant recipients

PURPOSE OF REVIEW

Kidney dysfunction is challenging in liver transplant candidates to determine whether it is reversible or not. This review focuses on the pertinent data on how to best approach liver transplant candidates with kidney dysfunction in the current era after implementing the simultaneous liver kidney (SLK) allocation policy and safety net.

RECENT FINDINGS

The implementation of the SLK policy inverted the steady rise in SLK transplants and improved the utilization of high-quality kidneys. Access to kidney transplantation following liver transplant alone (LTA) increased with favorable outcomes. Estimating GFR in liver transplant candidates remains challenging, and innovative methods are needed. SLK provided superior patient and graft survival compared to LTA only for patients with advanced CKD and dialysis at least 3 months. SLK can provide immunological protection against kidney rejection in highly sensitized candidates. Post-SLK transplant care is complex, with an increased risk of complications and hospitalization.

SUMMARY

The SLK policy improved kidney access and utilization. Transplant centers are encouraged, under the safety net, to reserve SLK for liver transplant candidates with advanced CKD or dialysis at least 3 months while allowing lower thresholds for highly sensitized patients. Herein, we propose a practical approach to liver transplant candidates with kidney dysfunction.

Clinical significance of amphiregulin in patients with chronic kidney disease

BACKGROUND

Amphiregulin (AREG) is a ligand of epidermal growth factor receptor (EGFR), which plays an important role in injury-induced kidney fibrosis. However, the clinical significance of serum soluble AREG in chronic kidney disease (CKD) is unclear. In this study, we elucidated the clinical significance of serum soluble AREG in CKD by analyzing the association of serum soluble AREG levels with renal function and other clinical parameters in patients with CKD.

METHODS

In total, 418 Japanese patients with CKD were enrolled, and serum samples were collected for the determination of soluble AREG and creatinine (Cr) levels, and other clinical parameters. Additionally, these parameters were evaluated after 2 and 3 years. Moreover, immunohistochemical assay was performed ate AREG expression in the kidney tissues of patients with CKD.

RESULTS

Soluble AREG levels were positively correlated with serum Cr (p < 0.0001). Notably, initial AREG levels were positively correlated with changes in renal function (ΔCr) after 2 (p < 0.0001) and 3 years (P = 0.048). Additionally, soluble AREG levels were significantly higher (p < 0.05) in patients with diabetic nephropathy or primary hypertension. Moreover, AREG was highly expressed in renal tubular cells in patients with advanced CKD, but only weakly expressed in patients with preserved renal function.

CONCLUSION

Serum soluble AREG levels were significantly correlated with renal function, and changes in renal function after 2 and 3 years, indicating that serum soluble AREG levels might serve as a biomarker of renal function and renal prognosis in CKD.

Impact of chronic kidney disease and end-stage renal disease on outcomes after complex endovascular and open aortic aneurysm repair

OBJECTIVE

Chronic kidney disease (CKD) and end-stage renal disease are traditionally associated with worse outcomes after endovascular aortic repair (EVAR) and open aneurysm repair (OAR) of abdominal aortic aneurysms (AAAs). However, there needs to be more data on complex AAA repair involving the aorta's visceral segment. This study stratifies complex AAA repair outcomes by CKD severity and dialysis dependence.

METHODS

All patients undergoing elective OAR and fenestrated/branched EVAR (F-BEVAR) for complex AAA with preoperative renal function data captured by the Vascular Quality Initiative between January 2003 and September 2020 were analyzed. Patients were stratified by CKD class as follows: normal/mild (CKD 1 and 2), moderate (CKD class 3a), moderate to severe (CKD 3b), severe (CKD class 4 and 5), and dialysis. Only patients with clamp sites above one of the renal arteries were included for complex OAR. For F-BEVAR, patients with proximal landing zones below zone 5 (above celiac artery) were included, and distal landing zones between zones 1 and 5 were excluded. Primary outcomes were perioperative and 1-year mortality. Predictors of mortality were identified by Cox multivariate regression models.

RESULTS

We identified 7849 elective complex AAA repairs: 4230 (54%) complex OARs and 3619 (46%) F-BEVARs. Most patients were White (89%) and male (74%), with an average age of 72 ± 8 years. The patients who underwent F-BEVAR were older and had more comorbidities. Elective F-BEVAR for complex AAA started in 2012 and increased from 1.4% in 2012 to 58% in 2020 (P < .001). The OAR cohort had more perioperative complications, but less 1-year mortality. The normal/mild CKD cohort had the highest 1-year survival compared with other groups after both complex OAR and F-BEVAR. On Cox regression analysis, when compared with CKD 1-2, worsening CKD stage (CKD 3b: hazard ratio [HR], 2.5; 95% confidence interval [CI], 1.82-3.40; P < .001; CKD 4-5: HR, 1.9; 95% CI, 1.16-3.26; P = .011; and dialysis: HR, 4.4; 95% CI, 2.53-7.72; P < .001) were independently associated with 1-year survival after F-BEVAR. After complex OAR, worsening CKD stage but not dialysis was associated with 1-year mortality compared with CKD 1-2 (CKD 3b: HR, 1.6; 95% CI, 1.13-2.35; P = .009; CKD 4-5: HR, 3.4; 95% CI, 2.03-5.79; P < .001).

CONCLUSIONS

CKD severity is an essential predictor of perioperative and 1-year mortality after complex AAA repair, irrespective of the treatment modality, which may reflect the natural history of CKD. Consideration should be given to raising the threshold for elective AAA repair in patients with moderate to severe CKD and end-stage renal disease, given the high 1-year mortality rate.

Has the time come for age-adapted glomerular filtration rate criteria to define chronic kidney disease: how soon is now?

PURPOSE OF REVIEW

The conventional definition of chronic kidney disease (CKD) primarily relies on the identification of albuminuria or a decline in estimated glomerular filtration rate (eGFR). For many years, a straightforward eGFR threshold of <60 ml/min/1.73 m 2 has been widely adopted as the standard for defining CKD. Nonetheless, this criterion fails to consider the natural aging process of the kidney, and this oversight may affect the accurate diagnosis of kidney disease particularly at the extremes of age.

RECENT FINDINGS

The fixed eGFR threshold of <60 ml/min/1.73 m 2 for defining CKD misses crucial opportunities for risk prevention. Studies have revealed that the eGFR threshold at which the risks for adverse long-term health outcomes such as mortality, cardiovascular events, and kidney failure begin to rise varies substantially by age. Specifically, this threshold is lower for the elderly and higher for young adults. Consequently, this results in the over-diagnosis of kidney disease in the elderly and the under-diagnosis of kidney disease in young adults.

SUMMARY

To address these limitations of the current CKD definition, we discuss a number of proposed age-adapted eGFR criteria and weigh their pros and cons against the current, simple, and universally accepted approach.

Resting strain analysis to identify myocardial ischemia in patients with advanced chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is associated with higher incidence of cardiovascular death. Screening for coronary artery disease in asymptomatic or mildly symptomatic patients is challenging.

OBJECTIVE

The aim of this study was to investigate the incremental value of resting deformation analysis in predicting positive results for myocardial ischemia during stress transthoracic echocardiography in patients with end-stage CKD.

METHODS

Sixty-one patients (mean age: 62.3 ± 11.8, 65.7% men) with end-stage CKD were included in the study. Patients underwent a resting transthoracic echocardiogram and a dobutamine stress contrast echo (DSE) protocol. Positive results of DSE were defined as stress-induced left ventricular (LV) wall motion abnormalities.

RESULTS

The study cohort had normal or mildly impaired systolic function: mean LV ejection fraction (EF) was 49.2% (±10.4) and mean LV global longitudinal strain (GLS) was 14.4% (±4.5). Half of our population had impaired left atrial (LA) strain: mean LA reservoir, conduit, and contractile reserve were 24.1% (±12.6), 10.6% (±5.9), and 13.6% (±9.2), respectively. DSE was positive for ischemia in 55.7%. A significant negative association with DSE results was found for LV EF, LV GLS and the conduit phase of LA strain. Both LV and LA dimensions showed positive correlation with presence of ischemia in DSE. Multivariate logistic regression analysis showed that LV GLS was independently associated with DSE (p = 0.007), after controlling for covariates, with high diagnostic accuracy.

CONCLUSION

Resting LV deformation could predict positive results during DSE, thus may be useful to better identify renal patients who might benefit from coronary artery screening.

Cost-effectiveness of sodium zirconium cyclosilicate for advanced chronic kidney patients in Singapore

INTRODUCTION

Hyperkalaemia (HK) is prevalent among patients with chronic kidney disease (CKD) and chronic heart failure, especially if they are treated with renin-angiotensin-aldosterone system inhibitors (RAASi). This study evaluated the cost-effectiveness of a newly developed anti-HK therapy, sodium zirconium cyclosilicate (SZC), to the current standard of care for treating HK in advanced CKD patients from the Singapore health system perspective.

METHODS

We adapted a global microsimulation model to simulate individual patients' potassium level trajectories with baseline potassium ≥5.5 mmol/L, CKD progression, changes in treatment, and other fatal and non-fatal events. Effectiveness data was derived from ZS-004 and ZS-005 trials. Model parameters were localised using CKD patients' administrative and medical records at the Singapore General Hospital Department of Renal Medicine. We estimated the lifetime cost and quality-adjusted life years (QALYs) of each HK treatment, and the incremental cost-effectiveness ratio of SZC.

RESULTS

SZC demonstrated cost-effectiveness with an incremental cost-effectiveness ratsio of SGD 45 068 per QALY over a lifetime horizon, below the willingness-to-pay threshold of SGD 90 000 per QALY. Notably, SZC proved most cost-effective for patients with less severe CKD who were concurrently using RAASi. Sensitivity analyses confirmed the robustness of the findings, accounting for alternative parameter values and statistical uncertainty.

CONCLUSION

This study establishes the cost-effectiveness of SZC as a treatment for HK, highlighting its potential to mitigate the risk of hyperkalaemia and optimise RAASi therapy. These findings emphasise the value of integrating SZC into the Singapore health system for improved patient outcomes and resource allocation.

Gender, age and nationality differences in chronic kidney disease prevalence in the emirate of Abu Dhabi, UAE

AIM

We aimed to better understand the prevalence of chronic kidney disease in Abu Dhabi, UAE, where a very diverse ethnic population lives, each with their own risk profile.

METHODS

Data were analysed on all patients who were tested for serum creatinine in December 2019 for 4 years within our healthcare network. We analysed data for kidney disease by age, gender and nationality to study differences in prevalence and risk.

RESULTS

The entire cohort (EC) consisted 1 925 672 samples from 703 122 patients. 24% of patients had GFR < 90 mL/min/1.73 m2 (CKD2-5), 4% had more severe kidney dysfunction (CKD3-5) and 2% had UACR >3 mg/mmol and with GFR > 90 (CKD1). The long follow-up (LFU) group comprised 45.6% of patients who had eGFR on at least two occasions more than 90 days apart, and of these 19.5% had sustained eGFR <90, and 5.2% had CKD3-5. Males had lower eGFR than females in the EC (RR 1.68) and the LFU group (RR 1.76). Emirati Females had the lowest prevalence in the EC (2.9%) and expatriate females in the LFU (3.5%) groups. The relative risks of CKD in expatriate males were highest in the EC (2.14) and the LFU (2.39) groups. When we looked at the age distribution by nationality there were highly significant differences in some populations being highly represented at younger ages.

CONCLUSION

The prevalence of kidney disease in Abu Dhabi has a male predominance, with younger expatriates highly represented. A targeted strategy to identify those at high risk may identify early CKD to prevent progression to end-stage kidney disease.

Prediction models for earlier stages of chronic kidney disease

PURPOSE OF REVIEW

Identifying patients with risk of developing progressive chronic kidney disease (CKD) early is an important step in improving kidney care. This review discusses four recently developed models, two which predict risk of new onset disease, and two which predict progression earlier in the course of disease.

RECENT FINDINGS

Several models predicting CKD incidence and progression have been recently developed and externally validated. A connecting theme across these models is the use of data beyond estimated glomerular filtration rate, allowing for greater accuracy and personalization. Two models were developed with stratification by diabetes status, displaying excellent model fit with and without variables like use of diabetes medication and hemoglobin A1C. Another model was designed to be patient facing, not requiring the knowledge of any laboratory values for use. The final model was developed using lab data and machine learning. These models demonstrated high levels of discrimination and calibration in external validation, suggesting suitability for clinical use.

SUMMARY

Models that predict risk of CKD onset and progression have the potential to significantly reduce disease burden, financial cost, and environmental output from CKD through upstream disease prevention and slowed progression. These models should be implemented and evaluated prospectively in primary care settings.

Development and Validation of the Rating of CKD Knowledge Among Older Adults (Know-CKD) With Kidney Failure

RATIONALE & OBJECTIVE

Few older adults with kidney failure engage in shared decision making (SDM) for kidney replacement therapy. The lack of instruments to assess SDM-relevant knowledge domains may contribute to this. We assessed the reliability and validity of a new instrument, the Rating of CKD Knowledge Older Adults (Know-CKD).

STUDY DESIGN

Multistage process, including a stakeholder-engaged development phase, pilot testing, and validation of a knowledge instrument using a cross-sectional survey of older adults with CKD.

SETTING & PARTICIPANTS

363 patients aged 70+years with nondialysis advanced chronic kidney disease (CKD) (estimated glomerular filtration rate [eGFR]<30mL/min/1.73m2) in Boston, Chicago, Portland, ME, and San Diego from June 2018 and January 2020.

EXPOSURE

Educational level, higher literacy (Single Item Literacy Screener [SILS]) and numeracy (Subjective Numeracy Scale [SNS]), having participated in clinic-sponsored dialysis education, and self-reported "feeling informed" about options for treatment.

OUTCOME

Validity and reliability of the Know-CKD instrument.

ANALYTICAL APPROACH

Reliability was assessed with the Kuder-Richardson-20 coefficient. Construct validity was demonstrated by testing a priori hypotheses using t test, analysis of variance (ANOVA) tests, and linear regression analyses.

RESULTS

The mean (± SD) participant age was 77.6±5.9 years, and mean eGFR was 22.7±7.2mL/min/1.73m2; 281 participants (78%) self-reported as White. The 12-item Know-CKD assessment had good reliability (Kuder-Richardson-20 reliability coefficient=0.75), and a mean score of 58.2% ± 22.3 SD. The subscales did not attain acceptable reliability. The proportion answering correctly on each item ranged from 20.1% to 91.7%. In examining construct validity, the hypothesized associations held; Know-CKD significantly associated with higher education (β=6.98 [95% CI, 1.34-12.61], P=0.02), health literacy (β = -12.67 [95% CI, -19.49 to-5.86], P≤0.001), numeracy per 10% higher (β=1.85 [95% CI, 1.02-2.69], P≤0.001), and attendance at dialysis class (β=18.28 [95% CI, 13.30-23.27], P≤0.001). These associations were also observed for the subscales except for prognosis (not associated with literacy or numeracy).

LIMITATIONS

Know-CKD is only available in English and has been used only in research settings.

CONCLUSIONS

For older adults facing dialysis initiation decisions, Know-CKD is a valid, reliable, and easy to administer measure of knowledge. Further research should examine the relationship of kidney disease knowledge and SDM, patient satisfaction, and clinical outcomes.

PLAIN-LANGUAGE SUMMARY

The Rating of CKD Knowledge Among Older Adults (Know-CKD) study measures knowledge of chronic kidney disease (CKD) and is designed for older adults. Most existing knowledge measures for CKD focus on people of all ages and all CKD stages. This measure is useful because it will allow researchers to assess how well patient education efforts are working. Patient education is a way to help patients make decisions about their care. We describe how the measure was developed by a team of doctors, researchers, and patients, and how the measure performed among persons with advanced CKD aged 70 years and older. Know-CKD can inform efforts to improve shared decision-making research and practice for older patients with kidney disease.

Serum PRO-C3 is useful for risk prediction and fibrosis assessment in MAFLD with chronic kidney disease in an Asian cohort

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is an emerging risk factor for chronic kidney disease (CKD). N-terminal propeptide of collagen type 3 (PRO-C3) is a biomarker of advanced fibrosis in MAFLD and PRO-C3 may be involved in renal fibrosis. We aimed to use PRO-C3 measurements to generate a new algorithmic score to test the prediction of MAFLD with chronic kidney disease (MAFLD-CKD).

METHODS

A derivation and independent validation cohort of 750 and 129 Asian patients with biopsy-confirmed MAFLD were included. Serum PRO-C3 concentration was measured and regression analyses were performed to examine associations with MAFLD-CKD. A derivative algorithm for MAFLD-CKD risk prediction was evaluated with receiver operator characteristic (ROC) curve analysis.

RESULTS

The study included two Asian cohorts (n = 180 with MAFLD-CKD; mean-eGFR: 94.93 mL/min/1.73 m2; median-urinary albumin-to-creatinine ratio: 6.58 mg/mmol). PRO-C3 was associated with the severity of MAFLD-CKD and independently associated with MAFLD-CKD (adjusted odds ratio = 1.16, 95% confidence interval [CI]: 1.08-1.23, p < .001). A new non-invasive score (termed PERIOD) including PRO-C3 efficiently predicted MAFLD-CKD (AUROC = .842, 95% CI: .805-.875). Accuracy, specificity and negative predictive values were 80.2%, 85.1% and 88.4%, respectively. In the validation cohort, the PERIOD score had good diagnostic performance (AUROC = .807, 95% CI: .691-.893) with similar results in all patient subgroups. In the MAFLD-CKD subgroup, the accuracy for identifying advanced fibrosis was further improved by combining the PRO-C3-based ADAPT with the Agile 3+ scores (AUROC = .90, 95% CI: .836-.964).

CONCLUSIONS

The PERIOD score is helpful for accurately predicting the risk of MAFLD-CKD. PRO-C3 can also be used to assess liver fibrosis in people with MAFLD-CKD.

Characteristics and predictors of chronic kidney disease in children with myelomeningocele: a nationwide cohort study

BACKGROUND

Myelomeningocele (MMC) is highly prevalent in developing countries, and MMC-related neurogenic bladder is an important cause of childhood chronic kidney disease (CKD). This nationwide study aimed to evaluate demographic and clinical features of pediatric patients with MMC in Turkey and risk factors associated with CKD stage 5.

METHODS

Data from children aged 0-19 years old, living with MMC in 2022, were retrospectively collected from 27 pediatric nephrology centers. Patients > 1 year of age without pre-existing kidney abnormalities were divided into five groups according to eGFR; CKD stages 1-5. Patients on dialysis, kidney transplant recipients, and those with eGFR < 15 ml/min/1.73 m2 but not on kidney replacement therapy at time of study constituted the CKD stage 5 group.

RESULTS

A total of 911 (57.8% female) patients were enrolled, most of whom were expectantly managed. Stages 1-4 CKD were found in 34.3%, 4.2%, 4.1%, and 2.4%, respectively. CKD stage 5 was observed in 5.3% of patients at median 13 years old (range 2-18 years). Current age, age at first abnormal DMSA scan, moderate-to-severe trabeculated bladder on US and/or VCUG, and VUR history were independent risk factors for development of CKD stage 5 (OR 0.752; 95%; CI 0.658-0.859; p < 0.001; OR 1.187; 95% CI 1.031-1.367; p = 0.017; OR 10.031; 95% CI 2.210-45.544; p = 0.003; OR 2.722; 95% CI 1.215-6.102; p = 0.015, respectively). Only eight CKD stage 5 patients underwent surgery related to a hostile bladder between 1 and 15 years old.

CONCLUSION

MMC-related CKD is common in childhood in Turkey. A proactive approach to neurogenic bladder management and early protective surgery in selected cases where conservative treatment has failed should be implemented to prevent progressive kidney failure in the pediatric MMC population in our country.

Dietary cholesterol intake is not associated with the development of chronic kidney disease: Results from two Korean cohort studies

BACKGROUND AND AIMS

Although dyslipidemia is a major risk factor for chronic kidney disease (CKD), the relationship between dietary cholesterol and CKD remains unknown. We investigated the association between cholesterol intake and CKD risk.

METHODS AND RESULTS

The Korea National Health and Nutrition Examination Survey (KNHANES) 2019-2021 (n = 13,769) and the Korean Genome and Epidemiology Study (KoGES) (n = 9225) data were used for this study. Cholesterol intake was assessed using a 24-h recall food frequency questionnaire, and participants were categorized into three groups (T1, T2, and T3) based on cholesterol intake. Primary outcomes were prevalence and incidence of CKD. Higher cholesterol intake was modestly associated with increased serum levels of total, low-density lipoprotein, and high-density lipoprotein cholesterol in the KNHANES. However, we found no significant association between cholesterol intake and CKD prevalence in the KNHANES, regardless of a history of hypercholesterolemia. In the KoGES, during a median follow-up of 11.4 years, cholesterol intake was not associated with incident CKD in participants without hypercholesterolemia (hazard ratio [HR] per 10 mg increase, 1.00; 95 % confidence interval [CI], 0.99-1.01) and in those with hypercholesterolemia (HR, 1.01; 95 % CI, 0.98-1.04). Egg consumption also showed no significant association with the risk of incident CKD. Additionally, cholesterol intake had no significant interaction on the relationships between serum cholesterol levels and incident CKD.

CONCLUSION

Although cholesterol intake was associated with increased serum cholesterol levels, it was not associated with CKD prevalence and incidence. Our findings suggest that reducing cholesterol intake alone may not be sufficient to prevent CKD.

Variations in Incidence and Prognosis of Stage 4 CKD Among Adults Identified Using Different Algorithms: A Population-Based Cohort Study

RATIONALE & OBJECTIVE

Clinical guidelines define chronic kidney disease (CKD) as abnormalities of kidney structure or function for>3 months. Assessment of the duration criterion may be implemented in different ways, potentially impacting estimates of disease incidence or prevalence in the population, individual diagnosis, and treatment decisions, especially for more severe cases. We investigated differences in incidence and prognosis of CKD stage G4 identified by 1 of 4 algorithms.

STUDY DESIGN

Population-based cohort study in Alberta, Canada.

SETTING & PARTICIPANTS

Residents>18 years old with incident CKD stage G4 (eGFR 15-29mL/min/1.73m2) diagnosed between April 1, 2015, and March 31, 2018, based on administrative and laboratory data.

EXPOSURE

Four outpatient eGFR-based algorithms, increasing in stringency, for defining cohorts with CKD G4 were evaluated: (1) a single test, (2) first eGFR<30mL/min/1.73m2 and a second eGFR 15-29mL/min/1.73m2 measured>90 days apart (2 tests), (3) ≥2 eGFR measurements of<30mL/min/1.73m2 sustained for>90 days (qualifying period) and the last eGFR in the qualifying period of 15-29mL/min/1.73m2 (relaxed sustained), and (4) ≥2 consecutive measurements of 15-29mL/min/1.73m2 for>90 days (rigorous sustained).

OUTCOME

Time to the earliest of death, eGFR improvement (a sustained increase in eGFR to≥30mL/min/1.73m2 for>90 days and>25% increase from the index eGFR), or kidney failure.

ANALYTICAL APPROACH

For each of the 4 cohorts, incidence rates and event-specific cumulative incidence functions at 1 year from cohort entry were estimated.

RESULTS

The incidence rates of CKD G4 decreased as algorithms became more stringent, from 190.7 (single test) to 79.9 (rigorous sustained) per 100,000 person-years. The 2 cohorts based on sustained reductions in eGFR were of comparable size and 1-year event-specific probabilities. The 2 cohorts based on a single test and a 2-test sequence were larger and experienced higher probabilities of eGFR improvement.

LIMITATIONS

A short follow-up period of 1 year and a predominantly White population.

CONCLUSIONS

The use of more stringent algorithms for defining CKD G4 results in substantially lower estimates of disease incidence, the identification of a group with a lower probability of eGFR improvement, and a higher risk of kidney failure. These findings can inform implementation decisions of disease definitions in clinical reporting systems and research studies.

PLAIN-LANGUAGE SUMMARY

Although guidelines recommend>3 months to define chronic kidney disease (CKD), the methods for defining specific stages, particularly G4 (eGFR 15-29mL/min/1.73m2) when referral to nephrology services is recommended, have been implemented differently across studies and surveillance programs. We studied differences in incidence and prognosis of CKD G4 cohorts identified by 4 algorithms using administrative and outpatient laboratory databases in Alberta, Canada. We found that, compared with a single-test definition, more stringent definitions resulted in a lower disease incidence and identified a group with worse short-term kidney outcomes. These findings highlight the impact of the choice of algorithm used to define CKD G4 on disease burden estimates at the population level, on individual prognosis, and on treatment/referral decisions.

Pubertal luteinizing hormone levels in children with chronic kidney disease and association with change in glomerular filtration rate

BACKGROUND

Children with chronic kidney disease (CKD) are at risk for abnormalities in pubertal development. We aimed to describe the timing of pubertal onset by luteinizing hormone (LH) levels and the association between hormonal onset of puberty with changes in GFR.

METHODS

Data from the Chronic Kidney Disease in Children (CKiD) study were collected prospectively. GFR was estimated at annual visits and measured by iohexol clearance every other year. LH was measured from stored repository serum samples in a nested sample of 124 participants. Hormonal onset of puberty was defined as LH level greater than or equal to 0.3 IU/L. A mixed effects model with random intercepts and slopes was used to compare the slope of decline of GFR before and after hormonal onset of puberty. The model was adjusted for age, glomerular disease diagnosis, baseline proteinuria on the log scale, and BMI.

RESULTS

Median age at hormonal onset of puberty was 9.9 years (IQR 8.1, 11.9) in girls and 10.2 years (IQR 9.2, 11.0) in boys. The mixed effects model showed faster decline in both estimated GFR and measured GFR in boys after hormonal onset of puberty (p < 0.001), and a similar but attenuated accelerated estimated GFR decline was observed for girls with no difference for measured GFR.

CONCLUSIONS

LH levels in the post-pubertal range were observed prior to clinical manifestations of puberty in children with CKD. Hormonal onset of puberty was associated with faster decline in GFR, particularly among boys with CKD.

Circulating miR-423-5p levels are associated with carotid atherosclerosis in patients with chronic kidney disease

BACKGROUND AND AIMS

Carotid atherosclerosis is associated with an elevated risk of stroke in patients with chronic kidney disease. However, the molecular basis for the incidence of carotid atherosclerosis in patients with CKD is poorly understood. Here, we investigated whether circulating miR-423-5p is a crucial link between CKD and carotid atherosclerosis.

METHODS AND RESULTS

We recruited 375 participants for a cross-sectional study to examine the occurrence of carotid plaque and plaque thicknesses. Levels of miR-423-5p were determined by qPCR analysis. We found that non-dialysis CKD patients had higher circulating exosomal and plasma miR-423-5p levels, and dialysis-dependent patients had lower miR-423-5p levels than non-dialysis CKD patients. After excluding for the influence of dialysis patients, linear regression analysis indicated that levels of circulating miR-423-5p are negatively correlated with eGFR (P < 0.001). Higher plasma miR-423-5p levels were associated with the incidence and severity of carotid plaques. In parallel, we constructed a murine model of CKD with a 5/6 nephrectomy protocol and performed RNA sequencing studies of aortic tissues. Consistent with these findings in CKD patients, circulating exosomal miR-423-5p levels in CKD mice were elevated. Furthermore, our RNA-seq studies indicated that the putative target genes of miR-423-5p were related to oxidative stress functions for aorta of CKD mice.

CONCLUSION

Levels of miR-423-5p are associated with the presence and severity of carotid plaque in CKD. Data from our mouse model suggests that miR-423-5p likely influences gene expression programs related to oxidative stress in aorta of CKD mice.

Development and validation of a race-agnostic computable phenotype for kidney health in adult hospitalized patients

Standard race adjustments for estimating glomerular filtration rate (GFR) and reference creatinine can yield a lower acute kidney injury (AKI) and chronic kidney disease (CKD) prevalence among African American patients than non-race adjusted estimates. We developed two race-agnostic computable phenotypes that assess kidney health among 139,152 subjects admitted to the University of Florida Health between 1/2012-8/2019 by removing the race modifier from the estimated GFR and estimated creatinine formula used by the race-adjusted algorithm (race-agnostic algorithm 1) and by utilizing 2021 CKD-EPI refit without race formula (race-agnostic algorithm 2) for calculations of the estimated GFR and estimated creatinine. We compared results using these algorithms to the race-adjusted algorithm in African American patients. Using clinical adjudication, we validated race-agnostic computable phenotypes developed for preadmission CKD and AKI presence on 300 cases. Race adjustment reclassified 2,113 (8%) to no CKD and 7,901 (29%) to a less severe CKD stage compared to race-agnostic algorithm 1 and reclassified 1,208 (5%) to no CKD and 4,606 (18%) to a less severe CKD stage compared to race-agnostic algorithm 2. Of 12,451 AKI encounters based on race-agnostic algorithm 1, race adjustment reclassified 591 to No AKI and 305 to a less severe AKI stage. Of 12,251 AKI encounters based on race-agnostic algorithm 2, race adjustment reclassified 382 to No AKI and 196 (1.6%) to a less severe AKI stage. The phenotyping algorithm based on refit without race formula performed well in identifying patients with CKD and AKI with a sensitivity of 100% (95% confidence interval [CI] 97%-100%) and 99% (95% CI 97%-100%) and a specificity of 88% (95% CI 82%-93%) and 98% (95% CI 93%-100%), respectively. Race-agnostic algorithms identified substantial proportions of additional patients with CKD and AKI compared to race-adjusted algorithm in African American patients. The phenotyping algorithm is promising in identifying patients with kidney disease and improving clinical decision-making.

Chronic kidney disease and cognitive performance: NHANES 2011-2014

PURPOSE

Previous studies suggest an association between chronic kidney disease (CKD) and cognitive impairment. The purpose of this study was to explore the association between the diverse stages of CKD and the cognitive performance of elderly American adults.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 were used. Multivariate adjusted logistic regression, subgroup analysis, and the restricted cubic spline model were used to assess the associations of CKD stage and estimated glomerular filtration rate (eGFR) with cognitive performance. The measures used to evaluate cognitive function included the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) test, the Animal Fluency test, and the Digit Symbol Substitution test (DSST).

RESULTS

This study included 2234 participants aged ≥ 60 years. According to the fully adjusted model, stages 3-5 CKD were significantly associated with the CERAD test score (OR = 0.70, 95% CI [0.51, 0.97], p = 0.033), the Animal Fluency test score (OR = 0.64, 95% CI [0.48, 0.85], p = 0.005), and the DSST score (OR = 0.60, 95% CI [0.41, 0.88], p = 0.013). In addition, the incidence of poor cognitive function increased with decreasing eGFR, especially for individuals with low and moderate eGFRs. Both the DSST score (p nonlinearity < 0.0001) and the Animal Fluency test score (p nonlinearity = 0.0001) had nonlinear dose-response relationships with the eGFR. However, a linear relationship was shown between the eGFR and CERAD test score (p nonlinearity = 0.073).

CONCLUSIONS

CKD, especially stages3-5 CKD, was significantly associated with poor cognitive performance in terms of executive function, learning, processing speed, concentration, and working memory ability. All adults with CKD should be screened for cognitive impairment.

Comprehensive geriatric assessment of older patients with renal disease: a cross-sectional survey

Multidimensional health function impairments are common in older patients with chronic kidney disease (CKD). The purpose of this study was to explore whether the risk or severity of geriatric syndrome increased with a decline in renal function. This survey was conducted for CKD patients aged  ≥ 60 years and hospitalized at West China Hospital of Sichuan University (Center of Gerontology and Geriatrics, Nephrology, and Endocrinology) and Chengdu Kangfu Kidney Disease Hospital from September 01, 2013 to June 30, 2014. Patients underwent multidimensional individualized assessments by trained doctors. Logistic regression analysis found that the risk of assisted walking (P = 0.001) and urinary incontinence (P = 0.039) increased with a decline in renal function. Regression analysis revealed that the scores of activities of daily living (P = 0.024), nutritional status (P = 0.000), total social support (P = 0.014), and objective support (P = 0.000) decreased with a decline in renal function.

UroAngel: a single-kidney function prediction system based on computed tomography urography using deep learning

BACKGROUND

Accurate estimation of the glomerular filtration rate (GFR) is clinically crucial for determining the status of obstruction, developing treatment strategies, and predicting prognosis in obstructive nephropathy (ON). We aimed to develop a deep learning-based system, named UroAngel, for non-invasive and convenient prediction of single-kidney function level.

METHODS

We retrospectively collected computed tomography urography (CTU) images and emission computed tomography diagnostic reports of 520 ON patients. A 3D U-Net model was used to segment the renal parenchyma, and a logistic regression multi-classification model was used to predict renal function level. We compared the predictive performance of UroAngel with the Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations, and two expert radiologists in an additional 40 ON patients to validate clinical effectiveness.

RESULTS

UroAngel based on 3D U-Net convolutional neural network could segment the renal cortex accurately, with a Dice similarity coefficient of 0.861. Using the segmented renal cortex to predict renal function stage had high performance with an accuracy of 0.918, outperforming MDRD and CKD-EPI and two radiologists.

CONCLUSIONS

We proposed an automated 3D U-Net-based analysis system for direct prediction of single-kidney function stage from CTU images. UroAngel could accurately predict single-kidney function in ON patients, providing a novel, reliable, convenient, and non-invasive method.

Determinants of early chronic kidney disease in patients with recently diagnosed type 2 diabetes mellitus: a retrospective study from the Taiwan Diabetes Registry

BACKGROUND

We tried to identify the risk factor associate with early chronic kidney disease (CKD) in recently diagnosed type 2 diabetes mellitus patients by utilizing real-world data from Taiwan Diabetes Registry.

MATERIALS AND METHODS

Patients with type 2 diabetes mellitus recently diagnosed within 1 year. We divided the study participants into control group and early CKD group. Early CKD was defined as either CKD stage G1 with albuminuria, CKD stage G2 with albuminuria, or CKD stage G3a regardless of albuminuria (Urine-albumin to creatinine ratio (UACR) ≥ 3 mg/mmol). Control group was defined as CKD G1 or CKD G2 without albuminuria. Logistic regression analyses were used to compare differences in clinical characteristics between the subgroups. Linear regression models were employed to examine the factors predicting estimated glomerular filtration rate (eGFR) and UACR.

RESULTS

Total 2217 patients with recently diagnosed type 2 diabetes mellitus were included. 1545 patients were assigned to control group and 618 patients were assigned to the early CKD group. Age (odds ratio (OR) 1.215, 95% confidence interval [CI] 1.122-1.316), systolic blood pressure (OR 1.203, 95% CI 1.117-1.296), glycated hemoglobin (OR 1.074, 95% CI 1.023-1.129) and triglyceride (OR 2.18, 95% CI 1.485-3.199) were found to be significant risk factors. Further, presence of bidirectional association between UACR and eGFR was found.

CONCLUSIONS

We reported factors associated with early CKD in recently diagnosed type 2 diabetes mellitus patients. Variables that associated with eGFR and UACR were identified respectively, included a mutual influence between UACR and eGFR.

Effect modification of polypharmacy on incident frailty by chronic kidney disease in older adults

BACKGROUND

Frailty and polypharmacy are common conditions in older adults, especially in those with chronic kidney disease (CKD). Therefore, we analyzed the association of polypharmacy and incident frailty and the effect modification by CKD in very old adults.

METHODS

In non-frail individuals within the Berlin Initiative (cohort) Study, polypharmacy (≥ 5 medications) was assessed according to multiple definitions based on the number of regular and on demand prescription and over the counter drugs, as well as vitamins and supplements. CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73m2 and/or an albumin-creatinine ratio ≥ 30 mg/g. Incident frailty was assessed at follow-up using Fried criteria. Logistic regression was applied to assess (1) the association of different polypharmacy definitions with incident frailty and (2) effect modification by CKD.

RESULTS

In this cohort study, out of 757 non-frail participants (mean age 82.9 years, 52% female, 74% CKD), 298 (39%) participants reported polypharmacy. Over the observation period of 2.1 years, 105 became frail. Individuals with polypharmacy had 1.96 adjusted odds (95% confidence interval (CI): 1.20-3.19) of becoming frail compared to participants without polypharmacy. The effect of polypharmacy on incident frailty was modified by CKD on the additive scale (relative excess risk due to interaction: 1.56; 95% CI 0.01-3.12).

CONCLUSIONS

This study demonstrates an association of polypharmacy and incident frailty and suggests strong evidence for an effect modification of CKD on polypharmacy and incident frailty. Revision of prescriptions could be a target strategy to prevent frailty occurrence, especially in older adults with CKD.

Frail hypertensive older adults with prediabetes and chronic kidney disease: insights on organ damage and cognitive performance - preliminary results from the CARYATID study

BACKGROUND

Hypertension and chronic kidney disease (CKD) pose significant public health challenges, sharing intertwined pathophysiological mechanisms. Prediabetes is recognized as a precursor to diabetes and is often accompanied by cardiovascular comorbidities such as hypertension, elevating the risk of pre-frailty and frailty. Albuminuria is a hallmark of organ damage in hypertension amplifying the risk of pre-frailty, frailty, and cognitive decline in older adults. We explored the association between albuminuria and cognitive impairment in frail older adults with prediabetes and CKD, assessing cognitive levels based on estimated glomerular filtration rate (eGFR).

METHODS

We conducted a study involving consecutive frail older patients with hypertension recruited from March 2021 to March 2023 at the ASL (local health unit of the Italian Ministry of Health) of Avellino, Italy, followed up after three months. Inclusion criteria comprised age over 65 years, prior diagnosis of hypertension without secondary causes, prediabetes, frailty status, Montreal Cognitive Assessment (MoCA) score < 26, and CKD with eGFR > 15 ml/min.

RESULTS

237 patients completed the study. We examined the association between albuminuria and MoCA Score, revealing a significant inverse correlation (r: 0.8846; p < 0.0001). Subsequently, we compared MoCA Score based on eGFR, observing a significant difference (p < 0.0001). These findings were further supported by a multivariable regression analysis, with albuminuria as the dependent variable.

CONCLUSIONS

Our study represents the pioneering effort to establish a significant correlation between albuminuria and eGFR with cognitive function in frail hypertensive older adults afflicted with prediabetes and CKD.

Estimated glomerular filtration rate in clinical practice: Consensus positioning of the Brazilian Society of Nephrology (SBN) and Brazilian Society of Clinical Pathology and Laboratory Medicine (SBPC/ML)

Chronic kidney disease (CKD) represents one of today's main public health problems. Serum creatinine measurement and estimation of the glomerular filtration rate (GFR) are the main tools for evaluating renal function. There are several equations to estimate GFR, and CKD-EPI equation (Chronic Kidney Disease - Epidemiology) is the most recommended one. There are still some controversies regarding serum creatinine measurement and GFR estimation, since several factors can interfere in this process. An important recent change was the removal of the correction for race from the equations for estimating GFR, which overestimated kidney function, and consequently delayed the implementation of treatments such as dialysis and kidney transplantation. In this consensus document from the Brazilian Societies of Nephrology and Clinical Pathology and Laboratory Medicine, the main concepts related to the assessment of renal function are reviewed, as well as possible existing controversies and recommendations for estimating GFR in clinical practice.

Representation of Real-World Adults With Chronic Kidney Disease in Clinical Trials Supporting Blood Pressure Treatment Targets

BACKGROUND

Little is known about how well trial participants with chronic kidney disease (CKD) represent real-world adults with CKD. We assessed the population representativeness of clinical trials supporting the 2021 Kidney Disease: Improving Global Outcomes blood pressure (BP) guidelines in real-world adults with CKD.

METHODS AND RESULTS

Using a cross-sectional analysis, we identified patients with CKD who met the guideline definition of hypertension based on use of antihypertensive medications or sustained systolic BP ≥120 mm Hg in 2019 in the Veterans Affairs and Kaiser Permanente of Southern California. We applied the eligibility criteria from 3 BP target trials, SPRINT (Systolic Pressure Intervention Trial), ACCORD (Action to Control Cardiovascular Risk in Diabetes), and AASK (African American Study of Kidney Disease), to estimate the proportion of adults with a systolic BP above the guideline-recommended target and the proportion who met eligibility criteria for ≥1 trial. We identified 503 480 adults in the Veterans Affairs and 73 412 adults in Kaiser Permanente of Southern California with CKD and hypertension in 2019. We estimated 79.7% in the Veterans Affairs and 87.3% in the Kaiser Permanente of Southern California populations had a systolic BP ≥120 mm Hg; only 23.8% [23.7%-24.0%] in the Veterans Affairs and 20.8% [20.5%-21.1%] in Kaiser Permanente of Southern California were trial-eligible. Among trial-ineligible patients, >50% met >1 exclusion criteria.

CONCLUSIONS

Major BP target trials were representative of fewer than 1 in 4 real-world adults with CKD and hypertension. A large proportion of adults who are at risk for cardiovascular morbidity from hypertension and susceptible to adverse treatment effects lack relevant treatment information.

Autosomal dominant chronic tubulointerstitial nephropathy: do not forget amyloidosis

Amyloidosis is a rare cause of inherited kidney disease, with most variants responsible for prominent glomerular involvement. In this issue, Kmochová et al. reported the first description of autosomal dominant medullary amyloidosis due to apolipoprotein A4 variants, resulting in slowly progressive chronic kidney disease with minimal proteinuria. Combining next-generation sequencing with histopathological studies incorporating Congo red staining and mass spectrometry should be considered in the diagnostic workup of hereditary tubulointerstitial disorders not identified after routine genetic testing.

Discrepancies among equations to estimate the glomerular filtration rate for drug dosing decision making in aged patients: a cross sectional study

BACKGROUND

Patients often require adjustments to drug doses due to impaired renal function. Glomerular filtration rate (GFR) estimation using various equations can result in discrepancies, potentially leading to different dose adjustment recommendations.

AIM

To determine the clinical significance of discrepancies observed between different equations used to estimate GFR for drug dose adjustments in a real-world group of patients over 65 years in primary care.

METHOD

The Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Berlin Initiative Study 1 equations were applied to estimate GFR in a group of patients over 65 years old attending a primary care center. Results were compared using Bland-Altman plots, and limits of agreement (LoA) and overall bias were calculated. Regression analyses were conducted to identify the null difference GFR and the slope of differences for each pairwise comparison.

RESULTS

A total of 1886 patients were analyzed. Differences between patient-adjusted and body surface area (BSA)-normalized versions of the equations were not clinically relevant for dose adjustments, with LoAs below 20 mL/min. However, discrepancies among the original versions of several equations presented LoAs over 30 mL/min. Greater differences were found between CG and MDRD or CKD-EPI equations.

CONCLUSION

Clinically relevant differences in GFR estimation were observed among different equations, potentially impacting drug dose adjustments. However, discrepancies were not considered significant when comparing patient-adjusted and BSA-normalized versions of the equations, particularly for patients with BSA close to the average.

Any reduction in maternal kidney mass makes a difference during pregnancy in gestational and fetal outcome

Little is known about the effect tubulointerstitial nephropathies have in modulating maternal-fetal outcomes in pregnancy. Therefore, we analyzed the main outcomes of pregnancy in these women to gain a better understanding of the role of a reduction in maternal kidney mass. From the Torino Cagliari Observational Study (TOCOS) cohort, we selected 529 patients with a diagnosis of tubulointerstitial disease and focused on 421 patients with chronic kidney disease (CKD) stage 1, without hypertension but with proteinuria less than 0.5 g/day at referral. From a cohort of 2969 singleton deliveries from low-risk pregnancies followed in the same settings we selected a propensity score matched control cohort of 842 pregnancies match 2:1 for age, parity, body mass index, ethnicity, and origin. Time to delivery was significantly shorter in the study cohort 38.0 (Quartile 1-Quartile 3: 37.0-39.0) versus 39.0 (Q1-Q3 38.0-40.0) weeks, with respect to controls. Incidence of delivery of less than 37 gestational weeks significantly increased from controls (7.4%) to women with previous acute pyelonephritis (10.8%), other tubulointerstitial diseases (9.7%) and was the highest in patients with a single kidney (31.1%). Similarly, neonatal birthweight significantly and progressively decreased from controls (3260 g [Q1-Q3: 2980-3530]), previous acute pyelonephritis (3090 g [Q1-Q3: 2868-3405], other tubulointerstitial diseases (3110 g [Q1-Q3: 2840-3417]), and to solitary kidney (2910 g [Q1-Q3: 2480-3240]). Risk of developing preeclampsia was significantly higher in the CKD cohort (3.6% vs 1.7% in low-risk controls). Thus, even a small reduction in functional kidney mass, such as a pyelonephritic scar, is associated with a shorter duration of pregnancy and an increased risk of preterm delivery. The risk is proportional to the extent of parenchymal reduction and is highest in cases with a solitary kidney.

Ultrasensitive sensing urinary cystatin C via an interface-engineered graphene extended-gate field-effect transistor for non-invasive diagnosis of chronic kidney disease

Early chronic kidney disease (CKD) has strong concealment and lacks an efficient, non-invasive, and lable-free detection platform. Cystatin C (Cys C) in urine is closely related to the progress of CKD (especially at the early stage), which is an ideal endogenous marker to evaluate the impairment of renal function. Thus, the accurate detection of urinary Cys C (u-Cys C) is great significant for early prevention and treatment and delaying the course of the disease of CKD patients. Herein, we developed an extended-gate field-effect transistor (EG-FET) sensor for ultrasensitive detection of u-Cys C, which consists of a monolithic interface-engineered graphene EG electrode array and a commercially available MOSFET. Laser-induced graphene (LIG) loaded with sputtered Au NPs in the presence of adhesive Cr (Au NPs/Cr/LIG) boosts the electrical performance of the EG electrode. Meanwhile, Au NPs also serve as linkers to immobilize papain that can selectively form protein complexes with Cys C. Supported by the synergistic effect of multilevel interface-engineered graphene, our sensor exhibits a good linear correlation within the u-Cys C concentration range of 5 ag/μL to 50 ng/μL with low detection limit of 0.05 ag/μL. Our work makes accurate, specific and rapid detection of u-Cys C feasible and promising for early screening for CKD.

Limitations of U25 CKiD and CKD-EPI eGFR formulae in patients 2-20 years of age with measured GFR > 60 mL/min/1.73 m2-a cross-sectional study

BACKGROUND

When applying Pierce U25 formula for estimating glomerular filtration rate (eGFR), we observed a higher proportion of eGFR < 90 mL/min/1.73 m2 (chronic kidney disease (CKD) stage 2). We compared agreement and accuracy of the Pierce U25 (ages 2-25), Pottel (ages 2-100), and CKD-EPI (ages 18-100) formulae to GFR measurements.

METHODS

Post hoc analysis of the three eGFRs compared to 367 99m technetium-diethylene-triamine penta-acetic acid (99Tc DTPA) GFR measurements (240 patients) using 3 sampling points and Brockner/Mørtensen correction (body surface area calculation based on ideal weight) on simultaneous serum creatinine and cystatin C measurements.

RESULTS

Overall, the U25 formula performed well with a Spearman r of 0.8102 (95% confidence interval 0.7706 to 0.8435, p < 0.0001) while diagnostic accuracy was low in patients with normal mGFR. The U25 formula reclassified 29.5% of patients with normal mGFR as CKD stage 2; whereas the average of the modified Schwartz formula based on serum creatinine and the Filler formula based on cystatin C, only over-diagnosed CKD stage 2 in 8.5%, 24.5% within 10% and 62.7% within 30%. We therefore combined both. The average Schwartz/Filler eGFR had 36.5% of results within 10%, 84.7% within 30%, and normal mGFR accuracy was 26.8%, 63.9% for 10% and 30%, respectively, outperforming the CKD-EPI and Pottel formulae.

CONCLUSIONS

The Pierce U25 formula results correlated well with mGFR < 75 mL/min/1.73 m2. Over the entire GFR range, accuracy was better for patients with a higher mGFR, when averaging the combined Schwartz/Filler formulae. More work is needed to prospectively confirm our findings in other centers.

Significance of LncRNAs in AKI-to-CKD transition: A therapeutic and diagnostic viewpoint

Acute kidney injury to chronic kidney disease (AKI-to-CKD) transition is a complex intermingling of characteristics of both AKI and CKD. Pathophysiologically, the transition lasts seven days after the AKI episode and thereafter silently progresses towards CKD. Growing reports confirm that the AKI-to-CKD transition is heavily regulated by epigenetic modifiers. Long non-coding RNAs (lncRNAs) share a diverse role in gene regulation at transcriptional and translational levels and have been reported to be involved in the regulation and progression of AKI-to-CKD transition. Several lncRNAs have been considered potential biomarkers for diagnosing kidney disease, including AKI and CKD. Targeting lncRNAs gives a promising therapeutic strategy against kidney diseases. The primitive role of lncRNA in the progression of the AKI-to-CKD transition is yet to be fully understood. As known, the lncRNAs could be used as a biomarker and a therapeutic target to halt the CKD development and progression after AKI. This review aims to deepen our understanding of the current knowledge regarding the involvement of lncRNAs in the AKI-to-CKD transition. This review primarily discusses the role of lncRNAs and the change in their mechanisms during different stages of kidney disease, such as in AKI, AKI-to-CKD transition, and CKD. Further, we have discussed the potential diagnostic and pharmacological outcomes of targeting lncRNAs to prevent or slow the progression of AKI-to-CKD transition.

Timing of Initiation of Xanthine Oxidase Inhibitors Based on Serum Uric Acid Level Does Not Predict Renoprognosis in Patients with Preserved Kidney Function

Background: Despite recent evidence of remaining possibility that early initiation of xanthine oxidase inhibitors (XOIs) is beneficial in renoprognosis for patients with stage 2 or less chronic kidney disease (CKD), no evidence is available regarding the difference in renoprognosis based on serum uric acid (sUA) levels at the initiation of XOIs among patients with preserved kidney function. Methods: New XOI initiators were divided into quartiles based on baseline sUA. Primary outcome was the composite incidence of a significant estimated glomerular filtration rate (eGFR) decline (≥40% decline in eGFR from baseline or development of eGFR <30 mL/1.73 m2/min) or all-cause death within 5 years. Results: After excluding inapplicable patients, 1170 XOI initiators were analyzed (mean ± standard deviation age: 68 ± 14.3 years; sUA: 10.6 ± 1.15 mg/dL). On overall median [interquartile range (IQR)] follow-up of 824 (342, 1576) days, incidence rate of the primary outcome was 287 per 1000 person-years for 5 years. Although the nonadjusted model showed a dose-response association between baseline sUA level and the outcome, the adjusted model showed no significant association. Adjusted hazard ratios (95% confidence interval) of the second, third, and fourth quartiles of baseline sUA with the composite outcome within 5 years compared to the first quartile were 1.00 (0.78, 1.29), 1.00 (0.80, 1.30), and 1.02 (0.80, 1.32), respectively. Conclusions: Early initiation of XOIs did not predict a significant benefit on renoprognosis even among the population with preserved kidney function. The validity of initiating XOIs with the aim of improving renoprognosis based on sUA is questionable.

Cardiogenic shock and chronic kidney disease: Dangerous liaisons

BACKGROUND

Chronic kidney disease (CKD) is one of the leading causes of death worldwide, closely interrelated with cardiovascular diseases, ultimately leading to the failure of both organs - the so-called "cardiorenal syndrome". Despite this burden, data related to cardiogenic shock outcomes in CKD patients are scarce.

METHODS

FRENSHOCK (NCT02703038) was a prospective registry involving 772 patients with cardiogenic shock from 49 centres. One-year outcomes (rehospitalization, death, heart transplantation, ventricular assist device) were analysed according to history of CKD at admission and were adjusted on independent predictive factors.

RESULTS

CKD was present in 164 of 771 patients (21.3%) with cardiogenic shock; these patients were older (72.7 vs. 63.9years) and had more comorbidities than those without CKD. CKD was associated with a higher rate of all-cause mortality at 1month (36.6% vs. 23.2%; hazard ratio 1.39, 95% confidence interval 1.01-1.9; P=0.04) and 1year (62.8% vs. 40.5%, hazard ratio 1.39, 95% confidence interval 1.09-1.77; P<0.01). Patients with CKD were less likely to be treated with norepinephrine/epinephrine or undergo invasive ventilation or receive mechanical circulatory support, but were more likely to receive renal replacement therapy (RRT). RRT was associated with a higher risk of all-cause death at 1month and 1year regardless of baseline CKD status.

CONCLUSIONS

Cardiogenic shock and CKD are frequent "cross-talking" conditions with limited therapeutic options, resulting in higher rates of death at 1month and 1year. RRT is a strong predictor of death, regardless of preexisting CKD. Multidisciplinary teams involving cardiac and kidney physicians are required to provide integrated care for patients with failure of both organs.

Does home blood pressure monitoring improve blood pressure-related outcomes in people living with chronic kidney disease? A systematic review

High blood pressure is an important risk factor for cardiovascular disease and disease progression in chronic kidney disease (CKD). Evidence on the effects of home blood pressure monitoring (HBPM) is limited. This review aimed to determine the effect of HBPM on systolic (SBP) and diastolic blood pressure (DBP) in patients with CKD. We searched medical literature databases for eligible studies presenting pre- and post-data for interventions utilizing HBPM. Study quality was assessed using the NHLBI tools for quality assessment. Heterogeneity prohibited a meta-analysis so estimates of effects were calculated along a sign test to examine the probability of observing the given pattern of positive effect direction. Eighteen studies were included (n = 1187 participants, mean age 56.7 [± 7.7] years). In 15 studies, HBPM was conducted within the context of additional high-level tailored support. Overall, the quality of n = 7/18 studies was rated as "good"; n = 6/18 were "fair," and n = 5/18 were rated as "poor." Interventions utilizing HBPM had a significant effect on SBP, with 14/16 studies favoring the intervention (88% [95% CI: 62%-98%], P = .002). Favorable effects were also seen on DBP (73% [95% CI: 45%-92%], P = .059). HBPM had a favorable effect on blood pressure goal attainment (86% [95% CI: 42%-100%], P = .062). HBPM in patients with CKD as part of a multicomponent intervention may lead to clinically significant reductions in blood pressure; however, research is needed to support the validity of this claim due to the high heterogeneity across the studies included.

Pediatric kidney dimensions and risk of persistent albuminuria in Mexican adolescents

In Mexico, chronic kidney disease of unknown origin is highly prevalent. Screening studies in adolescents have shown persistent microalbuminuria (pACR), adaptive podocytopathy and decreased kidney volume (KV). Here, we sought to develop normality tables of kidney dimensions by ultrasound in the Mexican state of Aguascalientes pediatric population (0 to 18y) and evaluate the relationship between the KV and pACR among the region's adolescents in a cross-sectional study. Kidney length (KL) and KV were determined by ultrasound. Our findings were compared with those in international literature of different populations where tables and graphs of normal kidney dimensions by ultrasound were reported. We compared organ dimensions in individuals above the age of 11 without albuminuria with those in patients with pACR recruited through screening studies in adolescents in Aguascalientes. This included 1068 individuals to construct percentile tables and graphs of the KL. Kidney dimensions were significantly lower when compared with all international comparisons. From a total 14,805 screen individuals, we compared 218 adolescents with pACR and 377 individuals without significant albuminuria. The Total KV adjusted to body surface (TKVBS) was significantly associated with pACR (odds ratio 1.03, 95% confidence interval 1.02-1.03). The upper quartile of TKVBS was highly associated with pACR (7.57, 4.13-13.87), hypertension (2.53, 1.66-3.86), and hyperfiltration (26 vs 11.5%). Thus, TKVBS is directly associated with pACR while greater KV, arterial hypertension, and hyperfiltration in patients with pACR suggest that the increase in volume is secondary to kidney hypertrophy. Additionally, the adaptative podocytopathy with low fibrosis seen on kidney biopsy which was performed in a subset of patients, and the smaller kidney dimensions in our population point to prenatal oligonephronia as the primary cause of the detected kidney disease.

Integrating essence of "time" for blood pressure control in nephrology care

Controlling blood pressure (BP) is essential in the management of patients with chronic kidney disease. Reflecting the intrinsic variability of BP, several parameters of BP over time have been shown to predict adverse outcomes. Systolic BP time in target range has been recently proposed as a new promising parameter. Park et al. confirmed its prognostic value in patients with chronic kidney disease. We review the potential clinical usefulness and challenges of this parameter in nephrology care.

[InspeCKD - Analysis of the use of diagnostics in patients at high risk for chronic kidney disease in German general practitioner (GP) practices]

BACKGROUND

Despite the high prevalence of chronic kidney disease (CKD) in Germany, only a small proportion of patients are currently diagnosed with CKD. Patients with hypertension, diabetes mellitus, and/or cardiovascular disease have a significantly increased risk of developing CKD and rapid disease progression and should therefore be screened and monitored in accordance with the guidelines.

OBJECTIVES

The aim of this retrospective, cross-sectional study was to gain insights into appropriate diagnosis of patients at risk for CKD in German general practitioner practices.

METHOD

For the analysis of the use of CKD-relevant diagnostics, electronic patient records from German general practitioner practices were analyzed. Adults with hypertension and/or diabetes mellitus and/or cardiovascular disease with a documented observation period of at least one year were included in the study.

RESULTS

Data from a total of 448,837 patients from 1244 general practitioner practices were analyzed. 75.8% of patients had hypertension, 35.1% had cardiovascular disease, and 32.4% had diabetes mellitus. During a mean observation period of 1.7 years, serum creatinine was assessed at least once in 45.5% of patients. A urine dipstick test for albuminuria was performed in 7.9% of patients and in 0.4% of patients, urine albumin-to-creatine ratio (UACR) was measured. Laboratory diagnostics were initiated a little more frequently in high-risk patients compared to the overall cohort.

CONCLUSIONS

The study highlights that despite known risk factors, guideline compliant CKD screening is rarely performed in German general practitioner practices, which implicates the need to increase the awareness of early diagnosis of CKD in patients at risk.

Associations of dietary inflammatory index with low estimated glomerular filtration rate, albuminuria and chronic kidney disease in U.S adults: Results from the NHANES 2011-2018

BACKGROUND AND AIMS

Chronic Kidney Disease (CKD) is characterized by a high inflammation status with ever-increasing prevalence, and defined as low estimated glomerular filtration rate (eGFR) or albuminuria. Both low eGFR and albuminuria can have independent effects on the body. The dietary inflammatory index (DII) is a validated tool used to assess the inflammatory potential of the diet. We aim to explore not only the association between DII and CKD, but also the associations of DII with low eGFR and albuminuria, respectively. In addition, their associations in different subgroups remain to be explored.

METHODS AND RESULTS

18,070 participants from the 2011-2018 NHANES with complete data of dietary intake and laboratory data were involved in our study. The data of 24-hour dietary recall interview was used to calculate DII, CKD could be reflected by laboratory data of creatinine and albumin. Then weighted multivariate logistic regression models and subgroup analyses were performed. The prevalence of low eGFR, albuminuria and CKD were 6.8%, 9.8% and 14.5%, respectively. A positive association between DII and low eGFR was observed (OR=1.12, 95%CI: 1.05-1.21), Q2, Q3 and Q4 are positively associated with a significant 39%, 65% and 71% increased risk of low eGFR compared with Q1 (P for trend<0.05). DII was also associated with CKD (OR=1.06, 95%CI: 1.01-1.11).

CONCLUSION

Significant positive associations of DII with CKD and low eGFR were observed. But we didn't find such association between DII and albuminuria.