Kidney Research and Clinical Practice最新文献

Background: This study aimed to develop a machine learning-based 2-year risk prediction model for early identification of patients with rapid progressive immunoglobulin A nephropathy (IgAN). We also assessed the model's performance to predict the long-term kidney-related outcome of patients.

Methods: A retrospective cohort of 1,301 patients with biopsy-proven IgAN from two tertiary hospitals was used to derive and externally validate a random forest-based prediction model predicting primary outcome (30% decline in estimated glomerular filtration rate from baseline or end-stage kidney disease requiring renal replacement therapy) and secondary outcome (improvement of proteinuria) within 2 years after kidney biopsy.

Results: For the 2-year prediction of primary outcomes, precision, recall, area-under-the-curve, precision-recall-curve, F1, and Brier score were 0.259, 0.875, 0.771, 0.242, 0.400, and 0.309, respectively. The values for the secondary outcome were 0.904, 0.971, 0.694, 0.903, 0.955, and 0.113, respectively. From Shapley Additive exPlanations analysis, the most informative feature identifying both outcomes was baseline proteinuria. When Kaplan-Meier analysis for 10-year kidney outcome risk was performed with three groups by predicting probabilities derived from the 2-year primary outcome prediction model (low, moderate, and high), high (hazard ratio [HR], 13.00; 95% confidence interval [CI], 9.52-17.77) and moderate (HR, 12.90; 95% CI, 9.92-16.76) groups showed higher risks compared with the low group. From the 2-year secondary outcome prediction model, low (HR, 1.66; 95% CI, 1.42-1.95) and moderate (HR, 1.42; 95% CI, 0.99-2.03) groups were at greater risk for 10-year prognosis than the high group.

Conclusion: Our machine learning-based 2-year risk prediction models for the progression of IgAN showed reliable performance and effectively predicted long-term kidney outcome.

Background: We aimed to investigate the change in the large middle molecule (>15 kDa) removal rate, which is associated with vascular calcification, when using a medium cut-off (MCO) dialyzer compared to a high-flux (HF) dialyzer.

Methods: Twenty patients with clinically stable maintenance hemodialysis were investigated over a 15-week study period. Dialyzer efficacies were evaluated during the last midweek hemodialysis treatment for each consecutive dialyzer membrane use: 1st HF, MCO, and 2nd HF dialyzer; 5 weeks each period. Changes in α1-microglobulin (33 kDa) during a dialysis session were analyzed to assess the efficacy of the MCO dialyzer as a reference. The levels and reduction ratios of fibroblast growth factor 23 (FGF23, 32 kDa), osteoprotegerin (OPG, 60 kDa), and sclerostin (22 kDa) were analyzed. Large middle molecules were measured using an enzyme-linked immunosorbent assay.

Results: Serum hemoglobin, phosphorus, and corrected calcium levels were not significantly different for each dialyzer period. Total protein and albumin values during the MCO dialyzer period did not decrease compared with the HF dialyzer period. The reduction ratio of α1-microglobulin was significantly higher in the MCO dialyzer than in the HF dialyzer (p < 0.001). The reduction ratios of FGF23 (p < 0.001), OPG (p < 0.001), and sclerostin (p < 0.001) were significantly higher in the MCO dialyzer than those in the HF dialyzer.

Conclusion: The reduction rate of large middle molecules related to vascular calcification, such as FGF23, OPG, and sclerostin, was significantly higher when using the MCO dialyzer than the HF dialyzer.

Background: Mental health affects well-being and physical health. Among adults with chronic kidney disease (CKD), mental health (MH) problems are common and can induce adverse clinical outcomes. We examined the association between patient-reported MH problems and clinical outcomes in adults with non-dialysis CKD.

Methods: This prospective observational study included 1,879 participants from the KNOW-CKD (KoreaN Cohort Study for Outcomes in Patients With CKD). Patients-reported MH problems were determined using four indicators of the Korea National Health and Nutrition Examination Survey questionnaire. We described the cross-sectional differences in health-related quality of life according to MH problems. We prospectively evaluated the hazard ratio (HR) of all-cause death and end-stage kidney disease (ESKD) according to the MH problems for a median follow-up of 6.4 years.

Results: The participants (mean age 53 years; 61.6% male) had patient-reported MH problems of inadequate sleep duration (17.4%), subjective distress (27.3%), depressive symptoms (13.2%), and suicidal ideation (16.8%). In the fully adjusted Cox proportional model, poor MH (≥2 problems) was associated with a high risk of ESKD (HR, 1.46; 95% confidence interval [CI], 1.18-1.08) and death (HR, 1.55; 95% CI, 1.04-2.32) compared with good MH. Furthermore, the single indicator of suicidal ideation was associated with a high risk of ESKD (HR, 1.37; 95% CI, 1.11-1.69) and death (HR, 1.98; 95% CI, 1.34-2.92).

Conclusion: Patient-reported MH problems are common in adults with CKD. Poor MH and only suicidal ideation are associated with a high risk of ESKD and early death. Age and sex modify the association between poor MH and adverse clinical outcomes in non-dialysis CKD.

Background: A functioning arteriovenous (AV) access is essential for hemodialysis efficiency and the quality of life in hemodialysis patients. Blood osteoprotegerin (OPG) and soluble receptor activator of nuclear factor kappa B ligand (RANKL) have been linked to cardiovascular diseases and vascular calcification. This study investigated the relationship between blood OPG, RANKL, and the occurrence of AV access thrombosis.

Methods: This prospective cohort study was conducted from August 2016 to August 2021 and included patients undergoing prevalent hemodialysis in two hospital-based hemodialysis units. Cox proportional hazards models and Kaplan-Meier analysis were used to evaluate the association between blood OPG, RANKL, and AV access (AV fistula [AVF] and AV graft [AVG]) outcomes.

Results: A total of 333 hemodialysis patients were enrolled, with an AV access thrombosis rate of 22.2%. Cox regression identified several factors associated with AV access thrombosis: AV access type (AVF vs. AVG; hazard ratio [HR], 0.24; p < 0.001), C-reactive protein (HR, 1.07; p = 0.002), and log-transformed OPG (HR, 5.52; p = 0.005). Subgroup analysis revealed high log-transformed OPG and RANKL were associated with AVF thrombosis (HR, 10.77; p = 0.002 and HR, 3.26; p = 0.009, respectively), while high C-reactive protein increased the risk of AVG thrombosis (HR, 1.31; p < 0.001). Kaplan-Meier analysis showed that patients with AVF in the highest tertile of log OPG (>402 pg/mL) had the highest AVF thrombosis incidence (p = 0.03).

Conclusion: High blood OPG was associated with AV access thrombosis, particularly in the AVF.

Background: Hypertension is one of the most important complications of chronic kidney disease (CKD) as it exacerbates disease progression in children. The aim of this study is to identify characteristics and factors associated with hypertension in children with CKD.

Methods: This is a cross-sectional study using baseline data from the 10-year ongoing cohort study named KNOW-PedCKD (Korean Cohort Study for Outcome in Patients with Pediatric Chronic Kidney Disease). We enrolled finally 378 patients aged <18 years at seven major pediatric nephrology centers in Republic of Korea. Blood pressure was measured and samples and clinical data were collected during the patients' annual hospital visits.

Results: We found that 30.7% of the patients had hypertension (n = 116); specifically, 16.4% (n = 62) had systolic hypertension, and 22.8% (n = 86) had diastolic hypertension. Multiple logistic regression analysis indicated that older age (odds ratio [OR], 1.13; p < 0.001), female sex (OR, 2.32; p = 0.002), a high left ventricular mass index (OR, 1.05; p < 0.001), and a high urine protein/creatinine ratio (OR, 1.12; p = 0.02) were significant associated factors for systolic or diastolic hypertension.

Conclusion: This study analyzed the associated factors for hypertension in children with CKD. Hypertension is associated with various factors, including age, sex, heart status, and proteinuria. Therefore, clinicians should consider these factors during patient evaluations to improve health outcomes.

Background: Membranous nephropathy (MN) is a specific autoimmune disease affecting kidneys. It is characterized by the accumulation of immune complexes in the glomerular basement membrane. Renal biopsy is currently the standard procedure to confirm the diagnosis, although the presence of autoantibodies against the phospholipase A2 receptor (PLA2R) can also help diagnose. In this study, we aimed to investigate the potential of urinary exosomes as noninvasive markers for diagnosing MN.

Methods: Exosomes were extracted from urine samples of five patients with MN and four healthy controls. The concentration of PLA2R was measured in both urine and isolated exosomes using enzyme-linked immunosorbent assay techniques. The measurements were adjusted based on the urine creatinine (UCr) level of each participant.

Results: The levels of PLA2R/UCr were investigated in urine and urine-derived exosomes from patients and controls. Results of the analysis revealed significantly higher expression of PLA2R/UCr in patients compared to the control group (p < 0.05). Furthermore, the expression level of PLA2R/UCr was higher in urine-derived exosomes than in urine samples. Additionally, a positive correlation was observed between the expression levels of PLA2R/UCr and the urine protein-to-creatinine ratio, with urine-derived exosomes exhibiting a stronger correlation than urine samples.

Conclusion: Studies have indicated that measuring exosomal PLA2R/UCr levels in urine could be a noninvasive method for diagnosing MN. Using urine-derived exosomes could also reduce the burden of performing a biopsy on patients and facilitate follow-up treatment, such as monitoring for future recurrence.

Background: Coronavirus disease 2019 (COVID-19) has led to severe pneumonia and mortality worldwide, however, clinical outcomes in end-stage renal disease patients remain unclear. This study evaluates the prognostic value of chest computed tomography (CT) findings in predicting COVID-19-related outcomes in prevalent hemodialysis patients.

Methods: We retrospectively analyzed 326 prevalent hemodialysis patients diagnosed with COVID-19 who underwent chest CT scans. Characteristics assessed included pleural effusion, lung involvement volume, nodular consolidation, patchy infiltration, and ground-glass opacity. Artificial intelligence (AI)-assisted CT analysis quantified lung involvement. The primary endpoint was in-hospital mortality. Clinical data were collected, and logistic regression analysis assessed the association between CT findings and mortality.

Results: The mean age of the patients was 66.7 ± 12.6 years, 61.0% were male, and 58.6% were diabetic. Chest CT showed that 18.1% had lung involvement >10%, 32.5% had pleural effusion, 68.7% had nodular consolidation, 57.1% had patchy infiltration, and 58.0% had ground-glass opacity. Seventy patients (21.5%) died. Multivariate logistic regression analysis identified lung involvement >2.7% (odds ratio [OR], 16.70; 95% confidence interval [CI], 4.35-65.63), pleural effusion (OR, 3.28; 95% CI, 1.15-9.35), nodular consolidation (OR, 4.08; 95% CI, 1.12-14.82), and patchy infiltration (OR, 3.75; 95% CI, 1.17-12.03) as significant mortality risk factors.

Conclusion: Chest CT findings, including lung involvement >2.7% and the presence of pleural effusion, nodular consolidation, and patchy infiltrates, significantly indicated mortality in COVID-19 pneumonia among prevalent hemodialysis patients. AI-assisted CT analysis proved useful in assessing lung involvement extent, showing that even minimal lung involvement can be associated with increased mortality.