Findings from the KNOW-CKD Study indicate that higher systolic blood pressure time in target range is associated with a lower risk of chronic kidney disease progression.

Time-in-target range (TTR) of systolic blood pressure (SBP) is determined by the proportion of time during which SBP remains within a defined optimal range. TTR has emerged as a useful metric for assessing SBP control over time. However, it is uncertain if SBP-TTR can predict the progression of chronic kidney disease (CKD). Here, we investigated the association between SBP-TTR during the first year of enrollment and CKD progression among 1758 participants from the KNOW-CKD (KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease). Baseline median estimated glomerular filtration rate (eGFR) was 51.7 ml/min per 1.73 m2. Participants were categorized into four SBP-TTR groups (0%, 1-50%, 51-99%, and 100%). The primary outcome was CKD progression defined as 50% or more decline in eGFR from baseline measurement or the initiation of kidney replacement therapy. During the follow-up period (9212 person-years over a median 5.4 years), the composite outcome occurred in 710 participants. In the multivariate cause-specific hazard model, a one-standard deviation increase in SBP-TTR was associated with an 11% lower risk of the composite outcome with hazard ratio, 0.89 (95% confidence interval, 0.82-0.97). Additionally, compared to patients with SBP-TTR 0%, the respective hazard ratios for those with SBP-TTR 1-50%, 51-99%, and 100% were 0.85 (0.68-1.07), 0.76 (0.60-0.96), and 0.72 (0.55-0.94), and the respective corresponding slopes of eGFR decline were -3.17 (-3.66 to -2.69), -3.02 (-3.35 to -2.68), -2.62 (-2.89 to - 2.36), and -2.33 (-2.62 to -2.04) ml/min/1.73 m2. Thus, higher SBP-TTR was associated with a decreased risk of CKD progression in patients with CKD.

Fenofibrate and risk of end-stage renal disease: A nationwide cohort study.

AIM: Previous studies have shown that fenofibrate improves outcomes such as albuminuria and estimated glomerular filtration rate decline. We hypothesize that fenofibrate has renoprotective effects and prevents or delays the development of end-stage renal disease. The objective of this study is to investigate the risk of incident end-stage renal disease in relation to fenofibrate treatment in patients who are already taking statins. MATERIALS AND METHODS: We performed a nationwide population-based cohort study using data from the Korea National Health Information Database from 2010 to 2017. Among adults using statins, 413 715 fenofibrate users were compared with 413 715 fenofibrate non-users after 1:1 age, sex and triglyceride matching. The endpoint of this study was incident end-stage renal disease. RESULTS: During a median 3.96-year follow-up, the incidence per 1000 person years of end-stage renal disease was lower in fenofibrate users than in fenofibrate non-users (0.885 vs. 0.960, p < 0.0001). The hazard ratio for end-stage renal disease was lower (0.763, 95% confidence interval 0.710-0.821) in fenofibrate users. This association was significant in patients with hypertension, proteinuria and an estimated glomerular filtration rate <60 mL/min/1.732. CONCLUSIONS: Fenofibrate use in patients taking statins with either hypertension, proteinuria, or decreased estimated glomerular filtration rate is associated with a low risk of incident end-stage renal disease. To confirm the renoprotective effect of fenofibrate in chronic kidney disease, a randomized controlled trial is warranted.

Circulating osteoprotegerin as a cardiac biomarker for left ventricular diastolic dysfunction in patients with pre-dialysis chronic kidney disease: the KNOW-CKD study.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a major cause of mortality in patients with chronic kidney disease (CKD), and diagnosis is challenging. Moreover, no specific biomarker for HFpEF has been validated in patients with CKD. The present study aimed to investigate the association between serum osteoprotegerin (OPG) levels and the risk of left ventricular diastolic dysfunction (LVDD), a surrogate of HFpEF, in patients with pre-dialysis CKD. METHODS: A total of 2039 patients with CKD at stage 1 to pre-dialysis 5 were categorized into quartiles (Q1 to Q4) by serum OPG levels, and were cross-sectionally analyzed. The study outcome was LVDD, which was operationally defined as the ratio of early transmitral blood flow velocity to early diastolic velocity of the mitral annulus (E/e') > 14. RESULTS: In the analysis of baseline characteristics, higher serum OPG levels were clearly related to the risk factors of HFpEF. A scatter plot analysis revealed a moderate correlation between serum OPG levels and E/e' (R = 0.351, P < 0.001). Logistic regression analysis demonstrated that the risk of LVDD in Q3 (adjusted odds ratio 2.576, 95% confidence interval 1.279 to 5.188) and Q4 (adjusted odds ratio 3.536, 95% confidence interval 1.657 to 7.544) was significantly higher than that in Q1. CONCLUSIONS: Elevated serum OPG levels are associated with the risk of LVDD in patients with pre-dialysis CKD. The measurement of serum OPG levels may help the diagnosis of LVDD, which is an important echocardiographic feature of HFpEF.

Kidney Health Plan 2033 in Korea: bridging the gap between the present and the future.

In response to the increase in the prevalence of chronic kidney disease (CKD) in Korea, the growth of patients requiring renal replacement therapy and the subsequent increase in medical costs, the rapid expansion of patients with end-stage kidney disease (ESKD), and the decrease in patients receiving home therapy, including peritoneal dialysis, the Korean Society of Nephrology has proclaimed the new policy, Kidney Health Plan 2033 (KHP 2033). KHP 2033 would serve as a milestone to bridge the current issues to a future solution by directing the prevention and progression of CKD and ESKD, particularly diabetic kidney disease, and increasing the proportion of home therapy, thereby reducing the socioeconomic burden of kidney disease and improving the quality of life. Here, we provide the background for the necessity of KHP 2033, as well as the contents of KHP 2033, and enlighten the Korean Society of Nephrology's future goals. Together with patients, healthcare providers, academic societies, and national policymakers, we need to move forward with goal-oriented drive and leadership to achieve these goals.

Importance of dialysis specialists in early mortality in elderly hemodialysis patients: a multicenter retrospective cohort study.

The early mortality rate in elderly patients undergoing hemodialysis is more than twice that in young patients, requiring more specialized healthcare. We investigated whether the number of professional dialysis specialists affected early mortality in elderly patients undergoing hemodialysis. This multicenter retrospective cohort study analyzed data from 1860 patients aged ≥ 70 years who started hemodialysis between January 2010 and December 2017. Study regions included Seoul, Gyeonggi-do, Gangwon-do, Daejeon/Chungcheong-do, Daegu/Gyeongsangbuk-do, and Busan/Ulsan/Gyeongsangnam-do. The number of patients undergoing hemodialysis per dialysis specialist was calculated using registered data from each hemodialysis center. Early mortality was defined as death within 6 months of hemodialysis initiation. Gangwon-do (28.3%) and Seoul (14.5%) showed the highest and lowest early mortality rate, respectively. Similarly, Gangwon-do (64.6) and Seoul (43.9) had the highest and lowest number of patients per dialysis specialist, respectively. Relatively consistent results were observed for the regional rankings of early mortality rate and number of patients per dialysis specialist. Multivariate Cox regression analysis-adjusted for previously known significant risk factors-revealed that the number of patients per dialysis specialist was an independent risk factor for early mortality (hazard ratio: 1.031, p < 0.001). This study underscores the growing need for dialysis specialists for elderly hemodialysis patients in Korea.

Association between dementia diagnosis at dialysis initiation and mortality in older patients with end-stage kidney disease in South Korea.

Background: The prevalence of dementia is 2- to 7-fold higher among patients with end-stage kidney disease (ESKD) than among the general population; however, its clinical implications in this population remain unclear. Therefore, this study aimed to determine whether comorbid dementia increases mortality among older patients with ESKD undergoing newly initiated hemodialysis. Methods: We analyzed data from the Korean Society of Geriatric Nephrology retrospective cohort, which included 2,736 older ESKD patients (≥70 years old) who started hemodialysis between 2010 and 2017. Kaplan-Meier survival and Cox regression analyses were used to examine all-cause mortality between the patients with and without dementia in this cohort. Results: Of the 2,406 included patients, 8.3% had dementia at the initiation of dialysis; these patients were older (79.6 ± 6.0 years) than patients without dementia (77.7 ± 5.5 years) and included more women (male:female, 89:111). Pre-ESKD diagnosis of dementia was associated with an increased risk of overall mortality (hazard ratio, 1.503; p < 0.001), and this association remained consistent after multivariate adjustment (hazard ratio, 1.268; p = 0.009). In subgroup analysis, prevalent dementia was associated with mortality following dialysis initiation in female patients, those aged <85 years, those with no history of cerebrovascular accidents or severe behavioral disorders, those not residing in nursing facilities, and those with no or short-term hospitalization. Conclusion: A pre-ESKD diagnosis of dementia is associated with mortality following dialysis initiation in older Korean population. In older patients with ESKD, cognitive assessment at dialysis initiation is necessary.

Impact of obesity on renal function in elderly Korean adults: a national population-based cohort study.

Background: Obesity is a well-known risk factor for chronic kidney disease and its progression. However, the impact of obesity on the renal function of the elderly population is uncertain. We investigated the association between obesity and renal outcomes in the elderly. Methods: We analyzed 130,504 participants from the Korean National Health Insurance Service-Senior cohort. Obesity was classified according to body mass index (BMI), sex-specific waist circumference (WC), and the presence of metabolic syndrome. The primary outcome was renal function decline, defined as a decline in the estimated glomerular filtration rate (eGFR) of at least 50% from baseline or new-onset end-stage renal disease. Results: During a follow-up period of 559,531.1 person-years (median, 4.3 years), 2,486 participants (19.0%; incidence rate of 4.44 per 1,000 person-years) showed renal function decline. A multivariate Cox proportional hazards model revealed that BMI/WC was not associated with renal function decline. However, the group with metabolic syndrome had a significantly increased risk of renal function decline compared to the group without metabolic syndrome (adjusted hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.13-1.36). Compared with the non-metabolic syndrome group, the adjusted HRs (95% CI) for participants with one through five components were 0.96 (0.84-1.11), 1.10 (0.96-1.27), 1.24 (1.06-1.45), 1.37 (1.12-1.66), and 1.99 (1.42-2.79), respectively (p for trend < 0.001). Conclusion: In elderly Korean adults, metabolic syndrome and the number of its components were associated with a higher risk of renal function decline, but BMI or WC was not significant.