Han, Seung Seok
Baek, Seon Ha
Ahn, Shin Young
Chin, Ho Jun
Na, Ki Young
Chae, Dong-Wan
Kim, Sejoong
Acute kidney injury (AKI) is a major health concern, because AKI is related with an increase in morbidity and mortality. Anemia is related to AKI in several clinical settings. However, the relationship between anemia and AKI and the effect of anemia on long-term mortality are unresolved in critically ill patients. A total of 2,145 patients admitted to the intensive care unit were retrospectively analyzed. We calculated a threshold value of hemoglobin associated with an increased risk of AKI and used this value to define anemia. The odds ratios (ORs) and hazard ratios for AKI and all-cause mortality were calculated after adjusting for multiple covariates. The OR of AKI increased depending on the decrease in hemoglobin level and the ideal threshold point of hemoglobin linked to increasing AKI risk was 10.5 g/dL. We categorized patients into anemia (< 10.5 g/dL) and non-anemia (=E2=89=A5 10.5 g/dL) groups. The risk of AKI was higher in the anemia group than the non-anemia group and this trend remained significant irrespective of the AKI development time (early vs. late) or duration (< 3 days vs. =E2=89=A5 3 days). Both anemia and AKI increased the 10-year mortality risk and this risk prediction was significantly separated by the presence of anemia and AKI. Furthermore, the risk prediction remained consistent irrespective of the AKI severity (i.e., recovery, stage, or duration of AKI). Based on these, we urge clinicians to monitor anemia and AKI in critically ill patients. =20
Park, Sehoon
Lee, Seung Mi
Park, Joong Shin
Hong, Joon-Seok
Chin, Ho Jun
Na, Ki Young
Kim, Dong Ki
Oh, Kook-Hwan
Joo, Kwon Wook
Kim, Yon Su
Lee, Hajeong
Background and objectives Although hemodynamic adaptation plays a crucial role in maintaining gestation, the clinical significance of midterm renal hyperfiltration (MRH) on pregnancy outcomes is unknown. Design, setting, participants, & measurements This was an observational cohort study. Women with a singleton pregnancy and a serum creatinine measurement during their second trimester were followed at two university hospitals in Korea between 2001 and 2015. Those with substantial renal function impairment or who delivered during the second trimester were not considered. MRH was represented by the highest eGFR, which was calculated using the Chronic Kidney Disease Epidemiology Collaboration method. An adverse pregnancy event was defined by the composition of preterm birth (gestational age <37 weeks), low birth weight (<2.5 kg), and preeclampsia. Results Data from 1931 pregnancies were included. The relationship between midterm eGFR and adverse pregnancy outcomes, which occurred in 538 mothers, was defined by a nonlinear U-shaped curve. The adjusted odds ratio and associated 95% confidence interval (95% CI) of an adverse pregnancy outcome for eGFR levels below and above the reference level of 120-150 ml/min per 1.73 m(2) were 1.97 (95% CI, 1.34 to 2.89; P < 0.001) for >=3D 150 ml/min per 1.73 m(2); 1.57 (95% CI, 1.23 to 2.00; P < 0.001) for 90-120 ml/min per 1.73 m(2); and 4.93 (95% CI, 1.97 to 12.31; P < 0.001) for 60-90 ml/min per 1.73 m(2). Moreover, among mothers without baseline CKD, women with adverse pregnancy outcomes had less prominent MRH than those without (P < 0.001). Conclusions We identified a unique U-shaped relationship between midterm eGFR and adverse pregnancy outcomes, and the optimal range of midterm eGFR levels was 120-150 ml/min per 1.73 m(2). In those without evident functional renal impairment, the absence of prominent MRH might be a significant risk factor for poor pregnancy outcomes.
Han, Seung Seok
Cho, Goo-Yeong
Park, Youn Su
Baek, Seon Ha
Ahn, Shin Young
Kim, Sejoong
Chin, Ho Jun
Chae, Dong-Wan
Na, Ki Young
Echocardiographic parameters can predict cardiovascular events in several clinical settings. However, which echocardiographic parameter is most predictive of each cardiovascular or non-cardiovascular event in patients starting hemodialysis remains unresolved. Echocardiography was used in 189 patients at the time of starting hemodialysis. We established primary outcomes as follows: cardiovascular events (ischemic heart disease, cerebrovascular disease, peripheral artery disease, and acute heart failure), fatal non-cardiovascular events, all-cause mortality, and all combined events. The most predictable echocardiographic parameter was determined in the Cox hazard ratio model with a backward selection after the adjustment of multiple covariates. Among several echocardiographic parameters, the E/e' ratio and the left ventricular end-diastolic volume (LVEDV) were the strongest predictors of cardiovascular and non-cardiovascular events, respectively. After the adjustment of clinical and biochemical covariates, the predictability of E/e' remained consistent, but LVEDV did not. When clinical events were further analyzed, the significant echocardiographic parameters were as follows: s' for ischemic heart disease and peripheral artery disease, LVEDV and E/e' for acute heart failure, and E/e' for all-cause mortality and all combined events. However, no echocardiographic parameter independently predicted cerebrovascular disease or non-cardiovascular events. In conclusion, E/e', s', and LVEDV have independent predictive values for several cardiovascular and mortality events. =20
Kim, Kipyo
Son, Hyung-Eun
Ryu, Ji-Young
Lee, Hajeong
Han, Seung Hyeok
Ryu, Dong-Ryeol
Paik, Jin Ho
Kim, Sejoong
Na, Ki Young
Chae, Dong-Wan
Chin, Ho Jun
Oh, Se Won
Cravedi, Paolo
Lee, Sung Woo
Baek, Seon Ha
Paik, Jin Ho
Kim, Sejoong
Na, Ki Young
Chae, Dong-Wan
Chin, Ho Jun
B7-1 is thought to play a pathogenic role in minimal-change disease (MCD). Recently, however, doubts have arisen regarding the role of B7-1 expression in MCD. Therefore, we aimed to identify the presence and clinical significance of B7-1 expression in MCD patients. The study participants included 28 adult MCD patients for whom kidney specimens were available. The intensity of B7-1 expression was assessed by two independent specialists. We analysed the association between the intensity of B7-1 expression and clinicopathological variables. No B7-1 expression in the glomeruli was observed in any of the 28 patients. Unexpectedly, however, 75.0% of the patients exhibited tubular B7-1 expression, with 35.7% demonstrating weak positive expressions and 39.3% demonstrating strong positive expressions. The level of proteinuria significantly increased as the intensity of tubular B7-1 expression increased. We also found trends of increasing blood urea nitrogen and serum creatinine levels with increased intensity of tubular B7-1 expression. However, we could not observe definite differences in long-and short-term clinical outcomes depending on the intensity of tubular B7-1 expression. In conclusion, B7-1 was expressed in renal tubular cells but not in glomeruli in adult MCD patients. The intensity of tubular B7-1 expression paralleled proteinuria levels, but not clinical outcomes.
Lee, Sung Woo
Lee, Anna
Yu, Mi-Yeon
Kim, Sun-wook
Kim, Kwang-il
Na, Ki Young
Chae, Dong-Wan
Kim, Cheol Ho
Chin, Ho Jun
Little is known about the clinical significance of frailty and changes of frailty after dialysis initiation in elderly patients with end-stage renal disease (ESRD). We prospectively enrolled 46 elderly patients with incident ESRD at a dialysis center of a tertiary hospital between May 2013 and March 2015. Frailty was assessed by using a comprehensive geriatric assessment protocol and defined as a multidimensional frailty score of >=3D 10. The main outcome was the composite of all-cause death or cardiovascular hospitalization, as determined in June 2016. The median age of the 46 participants was 71.5 years, and 63.0% of them were men. During the median 17.7 months follow-up, the rate of composite outcome was 17.4%. In multivariate logistic regression analysis, after adjusting for age, sex, diabetes, body mass index (BMI), and time of predialytic nephrologic care, female sex, and increased BMI were associated with increased and decreased odds of frailty, respectively. In multivariate Cox proportional hazards analysis, after adjusting for age, sex, diabetes, BMI, and time of predialytic nephrologic care, frailty was significantly associated with the composite adverse outcome. In repeated frailty assessments, the multidimensional frailty score significantly improved 12 months after the initiation of dialysis, which largely relied on improved nutrition. Therefore, frailty needs to be assessed for risk stratification in elderly patients with incident ESRD.
Lee, Sung Woo
Yu, Mi-Yeon
Lee, Hajeong
Ahn, Shin Young
Kim, Sejoong
Chin, Ho Jun
Na, Ki Young
BACKGROUND AND OBJECTIVES: Although acute kidney injury (AKI) is the most frequent complication in patients receiving extracorporeal membrane oxygenation (ECMO), few studies have been conducted on the risk factors of AKI. We performed this study to identify the risk factors of AKI associated with in-hospital mortality.; METHODS: Data from 322 adult patients receiving ECMO were analyzed. AKI and its stages were defined according to Kidney Disease Improving Global Outcomes (KDIGO) classifications. Variables within 24 h before ECMO insertion were collected and analyzed for the associations with AKI and in-hospital mortality.; RESULTS: Stage 3 AKI was associated with in-hospital mortality, with a hazard ratio (HR) (95% CI) of 2.690 (1.472-4.915) compared to non-AKI (p =3D 0.001). The simplified acute physiology score 2 (SAPS2) and serum sodium level were also associated with in-hospital mortality, with HRs of 1.02 (1.004-1.035) per 1 score increase (p =3D 0.01) and 1.042 (1.014-1.070) per 1 mmol/L increase (p =3D 0.003). The initial pump speed of ECMO was significantly related to in-hospital mortality with a HR of 1.333 (1.020-1.742) per 1,000 rpm increase (p =3D 0.04). The pump speed was also associated with AKI (p =3D 0.02) and stage 3 AKI (p =3D 0.03) with ORs (95% CI) of 2.018 (1.129-3.609) and 1.576 (1.058-2.348), respectively. We also found that the red cell distribution width (RDW) above 14.1% was significantly related to stage 3 AKI.; CONCLUSION: The initial pump speed of ECMO was a significant risk factor of in-hospital mortality and AKI in patients receiving ECMO. The RDW was a risk factor of stage 3 AKI.=20
Park, Sehoon
Baek, Seon Ha
Lee, Sung Woo
Lee, Anna
Chin, Ho Jun
Na, Ki Young
Kim, Yon Su
Chae, Dong-Wan
Han, Jin Suk
Kim, Sejoong
The clinical significance of elevated baseline serum potassium (K+) levels in hospitalised patients is rarely described. Hence, we performed a retrospective study assessing the significance of elevated K+ levels in a one-year admission cohort. Adult patients without hypokalaemia or end-stage renal disease were included. Adverse outcomes were all-cause mortality, hospital-acquired acute kidney injury, and events of arrhythmia. In total, 17,777 patients were included in the study cohort, and a significant difference (P < 0.001) was observed in mortality according to baseline serum K+ levels. The adjusted hazard ratios (HRs) and associated 95% confidence intervals (CIs) of all-cause mortality for K+ levels above the reference range of 3.6-4.0 mmol/L were as follows: 4.1-4.5 mmol/L, adjusted HR 1.075 (95% CI 0.981-1.180); 4.6-5.0 mmol/L, adjusted HR 1.261 (1.105-1.439); 5.1-5.5 mmol/L, adjusted HR 1.310 (1.009-1.700); > 5.5 mmol/L, adjusted HR 2.119 (1.532-2.930). Moreover, the risks of in-hospital acute kidney injury and arrhythmia were higher in patients with serum K+ levels above 4.0 mmol/L and 5.5 mmol/L, respectively. In conclusion, increased serum K+ levels, including mild elevations may be related to worse prognosis. Close monitoring and prompt correction of underlying causes or hyperkalaemia itself is warranted for admitted patients.
Jung, Ji Yong
Kim, Sejoong
Lee, Jay Wook
Jung, Eun Sook
Heo, Nam Ju
Son, Min-Jeong
Oh, Yun Kyu
Na, Ki Young
Han, Jin Suk
Joo, Kwon Wook
Jung JY, Kim S, Lee JW, Jung ES, Heo NJ, Son MJ, Oh YK, Na KY, Han JS, Joo KW. Effects of potassium on expression of renal sodium transporters in salt-sensitive hypertensive rats induced by uninephrectomy. Am J Physiol Renal Physiol 300: F1422-F1430, 2011. First published March 9, 2011; doi:10.1152/ajprenal.00598.2010.-Dietary potassium is an important modulator of systemic blood pressure (BP). The purpose of this study was to determine whether dietary potassium is associated with an altered abundance of major renal sodium transporters that may contribute to the modulation of systemic BP. A unilateral nephrectomy (uNx) was performed in male Sprague-Dawley rats, and the rats were fed a normal-salt diet (0.3% NaCl) for 4 wk. Thereafter, the rats were fed a high-salt (HS) diet (3% NaCl) for the entire experimental period. The potassium-repleted (HS + KCl) group was given a mixed solution of 1% KCl as a substitute for drinking water. We examined the changes in the abundance of major renal sodium transporters and the expression of mRNA of With-No-Lysine (WNK) kinases sequentially at 1 and 3 wk. The systolic BP of the HS + KCl group was decreased compared with the HS group (140.3 +/- 2.97 vs. 150.9 +/- 4.04 mmHg at 1 wk; 180.3 +/- 1.76 vs. 207.7 +/- 6.21 mmHg at 3 wk). The protein abundances of type 3 Na(+)/H(+) exchanger (NHE3) and Na(+)-Cl(-) cotransporter (NCC) in the HS + KCl group were significantly decreased (53 and 45% of the HS group at 1 wk, respectively; 19 and 8% of HS group at 3 wk). WNK4 mRNA expression was significantly increased in the HS + KCl group (1.4-fold of control at 1 wk and 1.9-fold of control at 3 wk). The downregulation of NHE3 and NCC may contribute to the BP-attenuating effect of dietary potassium associated with increased urinary sodium excretion.
Park, Sehoon
Lee, Soojin
Lee, Anna
Paek, Jin Hyuk
Chin, Ho Jun
Na, Ki Young
Chae, Dong-Wan
Kim, Sejoong
Postoperative acute kidney injury is associated with high mortality and poor prognosis. Additional investigations into the risk factors for this condition and the outcomes of patients who undergo surgeries under non-general anesthesia (GA) are necessary.This retrospective cohort study included data on all surgeries performed in adult patients from January 2006 to December 2015 at a tertiary hospital in Korea. Patients were divided into those undergoing surgeries with non-GA and those undergoing surgeries with GA. We analyzed the nephrological evaluation patterns, the risk factors for acute kidney injury, and prognoses after acute kidney injury by reviewing mortality, progression to end-stage renal disease, and serum creatinine doubling/estimated glomerular filtration rate halving from baseline.Of 74,524 patients, 20,332 underwent surgery with non-GA. These patients had baseline (adjusted odds ratio [OR], .68, 95% confidence interval [CI], .63-.72; P=E2=80=8A<=E2=80=8A.01] and follow-up serum creatinine levels (adjusted OR, .34; 95% CI, .33-.36; P=E2=80=8A<=E2=80=8A.01) less frequently measured than those undergoing GA. However, the incidence of acute kidney injury did not differ significantly between the 2 groups. Moreover, postoperative acute kidney injury after non-GA surgery showed a worse clinical prognosis which was similar with that of GA operations.Patients undergoing surgeries under non-GA did not receive sufficient evaluation for their risks of acute kidney injury. As an acute kidney injury in non-GA was associated a worse prognosis as in GA surgeries, more clinical attention should be considered.=20
Fu, Yan Yan
Kang, Kyung Ja
Ahn, Jung Myung
Kim, Hae-Ryoung
Na, Ki Young
Chae, Dong-Wan
Kim, Suhnggwon
Chin, Ho Jun
Oxidative stress is an important pathogenic factor in diabetes. Bilirubin may serve a cytoprotective function as an anti-oxidant. The Gunn rat lacks the enzyme uridine-diphosphate glucuronosyltransferase that is responsible for conjugation of bilirubin, exhibiting elevation of plasma bilirubin. We examined the effect of hyperbilirubinemia on the pancreatic damage caused by streptozotocin (STZ) in the Gunn rat. Male Wistar rats and male Gunn rats were treated with STZ (WS and GS groups, respectively) or vehicle (WC and GC groups, respectively). All 5 rats in the WS group developed diabetes, defined as fasting blood glucose 300 mg/dL or more, at 3 days, whereas only 2 of the 5 GS rats became diabetic at 7 days after STZ injection. Without insulin supplement at 7 days after STZ injection, the WS group displayed higher levels of fasting blood glucose (510.3 +/- 50.3 vs. 236.4 +/- 42.5 mg/dL, p = 0.003) and HbA1c (5.0 +/- 0.1 vs. 3.9 +/- 0.1, p = 0.001), compared to those of GS group. In Wistar rats, STZ induced apoptosis of the pancreatic islet cells, accompanied with activation of NADPH oxidase and increased production of reactive oxygen species and nitric oxide, but not in Gunn rats. Moreover, in a rat insulinoma cell line (RIN-m5F), pre-treatment with bilirubin (0.1 mg/dL) decreased cell death and apoptosis caused by STZ, and also reduced H(2)O(2) production. Considering the protective effect of hyperbilirubinemia against STZ-induced injury, we postulate that bilirubin could be a potential therapeutic modality for oxidative stress of pancreas islets.