Kidney Research and Clinical Practice最新文献

Background: Chronic kidney disease (CKD) patients are hospitalized for various conditions. Hospitalization increases the readmission rate and mortality rate, seriously deteriorating patients' quality of life. Consequently, it is crucial to analyze the reasons for hospitalization in CKD patients from a broader perspective according to CKD grade.

Methods: This is a prospective cohort study of CKD patients entitled the KoreaN cohort study for Outcomes in patients With Chronic Kidney Disease (KNOW-CKD). A total of 2,238 patients were examined, and the reasons for hospitalization were classified into 16 disease categories. The incidence rate ratio (IRR) according to CKD stage was compared using negative bimodal regression analysis.

Results: The all-cause hospitalization incidence was 184.96 per 1,000 person-years. The most common reason for hospitalization was circulatory system disease, followed by infection and digestive system disease. Among hospitalizations for acute kidney injury, endocrine-nutrition-metabolic-related illness, blood-related disease, and diseases of the nervous system and sensory organs, IRR increased as CKD grade advanced. The incidence of ophthalmologic surgery during hospitalization increased according to the CKD stage. The IRR of KNOW-CKD patients was 6.19 (95% confidence interval, 5.92-6.48; p < 0.001) compared with the general population.

Conclusion: This in-depth analysis of hospitalizations among CKD patients confirmed that CKD patients were hospitalized for various reasons, such as metabolic, ophthalmic, and hematologic diseases. Early detection and intervention regarding causative diseases of CKD are important to reduce the hospitalization burden and improve patients' quality of life.

Background: We aimed to investigate the association between systolic blood pressure (SBP) and risk of incident chronic kidney disease (CKD) using marginal structural model (MSM) to reflect mutual effects of exposure and confounders on the outcome.

Methods: A total of 195,970 adults with an estimated glomerular filtration rate (eGFR) of >60 mL/min/1.73 m2 and no proteinuria were included from a nationally representative sample cohort of Korean population. SBPs were measured through national health examinations. Primary outcome was incident CKD, defined as a composite of events of a decrease in eGFR to <60 mL/min/1.73 m2 or a newly developed proteinuria for at least two consecutive measurements. The association between SBP and risk of CKD was examined using Cox model, time-dependent Cox model, and MSM.

Results: During a follow-up of 5 years, CKD occurred in 3,355 participants (1.7%). With SBP treated as a continuous variable, each 10-mmHg increment was associated with higher risk for incident CKD, regardless of analytical models used. Compared to SBP group of 120-129 mmHg, hazard ratios (95% confidence intervals) for incident CKD for SBP groups of <110, 110-119, 130-139, and ≥140 mmHg in MSM were 0.70 (0.62-0.80), 0.85 (0.77-0.95), 1.16 (1.05-1.27), and 1.63 (1.47-1.80), respectively.

Conclusion: In this nationwide study, we found a significant relationship between higher SBP and higher risk of incident CKD. Further studies are warranted to verify the potential significance of high SBP as a preventable risk factor for the development of CKD in those with preserved renal function.

Background: This study investigates angiotensin II (Ang II)'s regulatory mechanism on renal outer medullary potassium channel (ROMK) activity in the distal convoluted tubule (DCT) during low potassium intake, focusing on the janus kinase 2 (JAK2) pathway activation mediated by the Ang II type 1 receptor (AT1R).

Methods: Utilizing a low potassium diet mouse model, various methods including patch clamping, reverse transcription-quantitative polymerase chain reaction, Western blotting, and immunohistochemical staining were applied to analyze ROMK channel activity and the expression of related proteins.

Results: The findings reveal that Ang II inhibits ROMK activity in the DCT2 membrane through AT1R activation, with the JAK2 pathway playing a central role. Further, inhibiting JAK2 reverses this effect, indicating its potential in hypertension treatment.

Conclusion: This study provides novel insights into the role of Ang II in renal potassium excretion and hypertension pathophysiology.

Background: Patients with end-stage kidney disease (ESKD) are more susceptible to viral epidemics and are known to have higher incidence and death rates of coronavirus disease 2019 (COVID-19) compared to the general population. We determined COVID-19 incidence and mortality among chronic hemodialysis (HD), peritoneal dialysis (PD), and kidney transplantation (KT) patients in Korea.

Methods: We conducted a retrospective cohort study and data regarding Korean ESKD adults (aged ≥18 years) were obtained from the National Health Insurance Service of Korea from October 2020 to December 2021. We examined and compared the incidence of COVID-19-related infections and deaths among the patients receiving HD, PD, and KT.

Results: Of all ESKD patients, 85,018 (68.1%) were on HD, 8,399 (6.7%) on PD, and 31,343 (25.1%) on KT. The COVID-19 incidence was 1.3% for HD, 1.2% for PD, and 1.5% for KT. COVID-19 mortality was 16.3% for HD, 12.2% for PD, and 4.7% for KT. PD patients had a lower incidence of infection compared to HD patients (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.607-0.93), but KT patients had a significantly higher risk of infection (OR, 1.28; 95% CI, 1.13-1.44). Compared with HD, the risk of COVID-19-related death was not different for PD patients but was significantly lower for KT patients (hazard ratio, 0.55; 95% CI, 0.35-0.88).

Conclusion: COVID-19 incidence was lower in PD patients than in HD patients, but mortality was not different between them. KT was associated with a higher risk of COVID-19 infection but lower mortality compared to HD.

Background: Digital health technologies have been rapidly adopted during the coronavirus disease 2019 pandemic. In Korea, a home care program, including face-to-face educational consultation and remote patient monitoring, was initiated to improve patients' quality of life. This study focused on patients with end-stage renal disease undergoing peritoneal dialysis to verify the long-term clinical effectiveness of this home care program.

Methods: This retrospective cohort study was designed as a pre-post study to analyze the clinical impact of a home care program for patients undergoing peritoneal dialysis in a single tertiary care hospital. A total of 186 patients were selected from June 2017 to May 2022 to identify clinical changes after program implementation by analyzing changes in peritonitis incidence and laboratory test results. Interrupted time series analyses with ordinary least squares linear regression and chi-square tests were used.

Results: At baseline, the incidence of peritonitis continuously increased by 0.480 cases per 1,000 patient-months (p = 0.02). After program initiation, the trend significantly decreased by 0.886 cases per 1,000 patient-months (p = 0.02). In addition, the proportion of individuals reaching the clinical target range had increased calcium levels (4.9%p, p = 0.003), stable hemoglobin (1.2%p, p = 0.477), phosphorus (2.8%p, p = 0.09), potassium (-1.6%p, p = 0.22), while parathyroid hormone levels decreased (-6.6%p, p = 0.005).

Conclusion: With a reduction in peritonitis incidence and overall improvement in laboratory test results, our study suggests that conducting a home care program for patients undergoing peritoneal dialysis is clinically effective.

Background: It is unclear whether poor glycemic control contributes to residual kidney function (RKF) decline and consequent volume overload in diabetic patients on peritoneal dialysis (PD).

Methods: This retrospective analysis included 80 diabetic patients who started PD at a single center. The first 2 years of patient data were collected to investigate the impact of glycemic control on RKF and volume overload in the early stages of PD. We used the time-averaged glycated hemoglobin (HbA1c) levels to estimate glycemic control. RKF loss was measured as the slope of RKF decline and time to anuria. To assess the association between glycemic control and volume overload, we examined technique failure (TF) associated with volume overload (TFVO), defined as TF due to excessive fluid accumulation. Multivariable linear regression and Cox regression analysis were performed to assess how glycemic control affects RKF and TFVO.

Results: Over the first 2 years, the mean rate of RKF decline was -3.25 ± 3.94 mL/min/ 1.73 m2 per year. Multivariable linear regression showed that higher time-averaged HbA1c was associated with a rapid RKF decline (β = -0.95; 95% confidence interval [CI], -1.66 to -0.24; p = 0.01). In the adjusted Cox regression analysis, higher time-averaged HbA1c increased the risk of progression to anuria (adjusted hazard ratio [HR], 1.97; 95% CI, 1.29-3.00; p = 0.002) and TFVO (adjusted HR, 2.88; 95% CI, 1.41-5.89; p = 0.004).

Conclusion: Poor glycemic control is associated with rapid RKF decline and leads to volume overload in diabetic patients on PD.

Background: The global coronavirus disease 2019 (COVID-19) pandemic has placed patients with end-stage kidney disease (ESKD) at heightened risk owing to their vulnerability to infections. Our study focused on patients with ESKD, examining COVID-19 incidence, hospitalization, and mortality in relation to their renal replacement therapy (RRT) type and identifying factors influencing COVID-19 hospitalization.

Methods: We conducted a retrospective cohort study using health insurance claims data from the Health Insurance Review and Assessment Service for patients with ESKD between July 2017 and June 2022. COVID-19 data for the general population were sourced from the Korea Disease Control and Prevention Agency.

Results: Patients undergoing hemodialysis (HD) constituted 90.7% of the cohort, followed by kidney transplantation (KT) recipients and peritoneal dialysis (PD). After adjusting for every 10,000 individuals, KT recipients exhibited the highest COVID-19 incidence, followed by those undergoing HD and PD, whereas the general population showed a higher infection rate of 43.64. Patients undergoing HD had the highest hospitalization rates, followed by KT recipients and those undergoing PD. The mortality rate per 10,000 individuals was highest in HD, followed by PD, the general population, and KT. Multivariate analysis indicated that age, RRT duration, residence in a nursing hospital, and comorbidities were associated with COVID-19 hospitalization.

Conclusion: Among RRT modalities, KT recipients displayed the highest COVID-19 incidence, whereas those undergoing HD exhibited the highest hospitalization and mortality rates. This study contributes to our understanding of infectious diseases in patients on RRT and aids in preparedness for future infectious disease outbreaks.

Background: South Korea has universal health coverage guaranteeing equitable healthcare for all. However, equity issues have been raised regarding hemodialysis reimbursement for medical aid recipients with chronic kidney disease. Physicians and civic groups demanded a revision of the discriminatory policy, and in response, the Ministry of Health and Welfare amended the hemodialysis case payment scheme. This study aims to evaluate the effectiveness of the reform and detect any unintended policy outcomes.

Methods: Data from the Health Insurance Review and Assessment Service of Korea was used. All subjects were patients with chronic kidney disease who received outpatient hemodialysis and medical aid from April 2017 to March 2022. The dzata was analyzed with descriptive statistics, and the generalized estimation equation was used to control for covariates and identify policy effects.

Results: The reform of the case payment scheme in 2021 raised the compensation level per hemodialysis case, which was fixed for 7 years from 2014, by approximately 2,000 Korean won. There was no negative effect such as additional expenditure resulting from an unintentional increase in medical use.

Conclusion: A year has passed since the implementation of the outpatient hemodialysis rate system reform for medical aid recipients. Our results indicate that the reform has gone smoothly, and we anticipate continuous efforts by the government to guarantee universal health coverage to medical aid recipients. Through such consistent endeavors to correct the discriminatory aspects of policies, South Korea will achieve true universal health coverage.