Jayoun Kim - Academia.edu (original) (raw)

Papers by Jayoun Kim

Scientific Reports, Mar 2, 2023

The causes of chronic kidney disease (CKD) affects its outcomes. However, the relative risks for ... more The causes of chronic kidney disease (CKD) affects its outcomes. However, the relative risks for adverse outcomes according to specific causes of CKD is not well established. In a prospective cohort study from KNOW-CKD, a cohort was analyzed using overlap propensity score weighting methods. Patients were grouped into four categories according to the cause of CKD: glomerulonephritis (GN), diabetic nephropathy (DN), hypertensive nephropathy (HTN), or polycystic kidney disease (PKD). From a total of 2070 patients, the hazard ratio of kidney failure, the composite of cardiovascular disease (CVD) and mortality, and the slope of the estimated glomerular filtration rate (eGFR) decline according to the cause of CKD were compared between causative groups in a pairwise manner. There were 565 cases of kidney failure and 259 cases of composite CVD and death over 6.0 years of follow-up. Patients with PKD had a significantly increased risk for kidney failure compared to those with GN [Hazard ratio (HR) 1.82], HTN (HR 2.23), and DN (HR 1.73). For the composite outcome of CVD and death, the DN group had increased risks compared to the GN (HR 2.07), and HTN (HR 1.73) groups but not to the PKD group. The adjusted annual eGFR change for the DN and PKD groups were − 3.07 and − 3.37 mL/min/1.73 m 2 per year, respectively, and all of these values were significantly different than those of the GN and HTN groups (− 2.16 and − 1.42 mL/min/1.73 m 2 per year, respectively). In summary, the risk of kidney disease progression was relatively higher in patients with PKD compared to other causes of CKD. However, the composite of CVD and death was relatively higher in patients with DN-related CKD than in those with GN-and HTN-related CKD. Chronic kidney disease (CKD), which is rapidly increasing in prevalence and incidence, is a heterogeneous set of diseases caused by various risk factors and comorbid conditions 1-5. Although CKD patients share similar pathophysiologies involved with the kidney disease progression, the course and speed of CKD progression and associated complications differ according to the underlying causes. Therefore in the KDIGO guidelines, the cause of CKD is considered one of the important predictors of the outcome, together with other variables such as the glomerular filtration rate category, the albuminuria category, and other comorbid conditions 5. However,

Nephrology Dialysis Transplantation, Jun 1, 2020

BMC Medical Research Methodology, Mar 6, 2019

Background: In clinical trials and survival analysis, participants may be excluded from the study... more Background: In clinical trials and survival analysis, participants may be excluded from the study due to withdrawal, which is often referred to as lost-to-follow-up (LTF). It is natural to argue that a disease would be censored due to death; however, when an LTF is present it is not guaranteed that the disease has been censored. This makes it important to consider both cases; the disease is censored or not censored. We also note that the illness process can be censored by LTF. We will consider a multi-state model in which LTF is not regarded as censoring but as a non-fatal event. Methods: We propose a multi-state model for analyzing semi-competing risks data with interval-censored or missing intermediate events. More precisely, we employ the additive and multiplicative hazards model with log-normal frailty and construct the conditional likelihood to estimate the transition intensities among states in the multi-state model. Marginalization of the full likelihood is accomplished using adaptive importance sampling, and the optimal solution of the regression parameters is achieved through the iterative quasi-Newton algorithm. Results: Simulation is performed to investigate the finite-sample performance of the proposed estimation method in terms of the relative bias and coverage probability of the regression parameters. The proposed estimators turned out to be robust to misspecifications of the frailty distribution. PAQUID data have been analyzed and yielded somewhat prominent results. Conclusions: We propose a multi-state model for semi-competing risks data for which there exists information on fatal events, but information on non-fatal events may not be available due to lost to follow-up. Simulation results show that the coverage probabilities of the regression parameters are close to a nominal level of 0.95 in most cases. Regarding the analysis of real data, the risk of transition from a healthy state to dementia is higher for women; however, the risk of death after being diagnosed with dementia is higher for men.

Annals of Surgical Oncology, Aug 17, 2017

Background. Mammography detects calcium deposits sensitively, but the specificity for differentia... more Background. Mammography detects calcium deposits sensitively, but the specificity for differentiating malignancy from benign calcifications is low. Thus, we investigated whether adjunctive breast-specific gamma imaging (BSGI) has incremental value for detecting cancer in women with suspicious calcifications detected by mammography, and compared BSGI with adjunctive ultrasonography (US). Methods. The medical records of women without a personal history of breast cancer who underwent mammography for breast evaluation from 2009 to 2014 were reviewed retrospectively. Patients who had calcifications detected by mammography, with a result of Breast Imaging Reporting and Data System (BI-RADS) categories 3-5, underwent adjunctive US and BSGI and were included in this study. A total of 302 breast lesions in 266 women (mean age ± standard deviation 49 ± 9 years) were selected for this study. Results. For detecting breast cancer using mammography plus BSGI, the sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating curve with 95% confidence intervals were 94% (91-96), 90% (86-93), 91% (87-94), 94% (90-96), and 0.92 (0.89-0.95), respectively. For mammography plus US, the respective values were 97% (94-98), 51% (46-57), 68% (63-73), 94% (90-96), and 0.74 (0.70-0.78). Conclusions. Adjunctive BSGI had higher specificity than adjunctive US without loss of sensitivity. This finding suggests that adjunctive BSGI may be a useful complementary initial imaging method to improve the detection of breast cancer in women who have calcifications with suspicious morphology at mammography.

Cancer genetics, Mar 1, 2014

The cytogenetic pathogenesis of bile duct cancer is poorly understood. Array comparative genomic ... more The cytogenetic pathogenesis of bile duct cancer is poorly understood. Array comparative genomic hybridization was performed on samples obtained from 24 patients with bile duct cancer and 10 normal healthy controls. Bile duct cancer patients had means of 21.8 gains and 19.2 losses of genes. We identified 20 novel copy number variation (CNV) regions that differed significantly between bile duct cancer patients and normal controls. Significant gains of copy number were observed at 2p11.2, 5p15.33, 22q11.21, 22q11.22, 22q11.23, 22q12.2, 22q12.3, 22q13.1, 22q13.31, and 22q13.33 and significant losses of copy number were observed at 8q11.21, 10q26.3, 11p15.4, 18q21.31, and 18q23. These loci included 153 genes, with 65% located at 22q11-q13. Oncostatin M signaling via the JAK/STAT pathway was the most relevant pathway, with immunohistochemical staining showing that OSM and LIF, both included in this pathway, were overexpressed in tumors. Copy number gains at 5p15.33 and 22q13.33 were correlated with early systemic recurrence in the bile duct cancer patients. In conclusion, copy number gains at 22q11-q13 were the most frequent and were correlated with poor disease-free survival. In-depth investigations are required to determine whether chromosomal aberrations at this locus are genetic markers of patient prognosis.

Nephrology, Oct 1, 2019

Objective: Although blood pressure (BP) variability has been regarded as a risk factor for hemorr... more Objective: Although blood pressure (BP) variability has been regarded as a risk factor for hemorrhagic transformation (HTF) after intravenous thrombolysis, its effect on HTF after endovascular recanalization therapy (ERT) remains to be elucidated. We aimed to study the relationship between BP variability and symptomatic intracerebral hemorrhage (sICH) after successful recanalization with ERT. Methods: A total of 211 patients with acute ischemic stroke and successful recanalization (thrombolysis in cerebral infarction 2b or 3) after ERT were included between January 2013 and May 2017. The BP data following ERT was obtained over the first 24 hours using parameters including mean, maximum, minimum, difference between maximum and minimum, standard deviation, coefficient of variation, successive variations, and time rate (TR) of BP variation for systolic BP (SBP) and diastolic BP. sICH was defined as parenchymal hemorrhage type 2 with neurological deterioration of 4 points of more on the National Institute of Health Stroke Scale. Results: Among the included patients, 20 (9.5%) developed sICH after successful ERT. The parameters linked with BP fluctuation over time were significantly related to sICH. After adjusting for confounders, the TR of SBP (per 0.1 mmHg/min increase) variation was independently associated with sICH (odds ratio = 1.71, 95% confidence interval = 1.013-2.886). Interpretation: Time-related BP variability in the first 24 hours following successful ERT was more correlated with sICH than other absolute BP levels. This suggests that maintaining a stable BP may be an important factor in preventing sICH after successful ERT.

Journal of Affective Disorders, Oct 1, 2014

Nephrology Dialysis Transplantation, Jun 24, 2020

Background. Diet is a modifiable factor of chronic kidney disease (CKD) progression. However, the... more Background. Diet is a modifiable factor of chronic kidney disease (CKD) progression. However, the effect of dietary salt intake on CKD progression remains unclear. Therefore, we analyzed the effect of dietary salt intake on renal outcome in Korean patients with CKD. Methods. We measured 24-h urinary sodium (Na) excretion as a marker of dietary salt intake in the prospective, multi-center, longitudinal KoreaN cohort study for Outcome in patients With CKD (KNOW-CKD). Data were analyzed from CKD patients at Stages G3a to G5 (n ¼ 1254). We investigated the association between dietary salt intake and CKD progression. Patients were divided into four quartiles of dietary salt intake, which was assessed using measured 24-h urinary Na excretion. The study endpoint was composite renal outcome, which was defined as either halving the estimated glomerular filtration rate or developing end-stage renal disease. Results. During a median (interquartile range) follow-up of 4.3 (2.8-5.8) years, 480 (38.7%) patients developed the composite renal event. Compared with the reference group (Q2, urinary Na excretion: 104.2 Na excretion < 145.1 mEq/day), the highest quartile of measured 24-h urinary Na excretion was associated with risk of composite renal outcome [Q4, urinary Na excretion !192.9 mEq/day, hazard ratio 1.8 (95% confidence interval 1.12-2.88); P ¼ 0.015] in a multivariable hazards model. Subgroup analyses showed that high-salt intake was particularly associated with a higher risk of composite renal outcome in women, in patients <60 years of age, in those with uncontrolled hypertension and in those with obesity. Conclusions. High salt intake was associated with increased risk of progression in CKD.

Gynecologic Oncology, Jul 1, 2016

This study aimed to establish a nomogram to predict microscopic parametrial infiltration (PMI) by... more This study aimed to establish a nomogram to predict microscopic parametrial infiltration (PMI) by combining preoperative clinicopathologic factors in FIGO stage IB cervical cancer patients treated by radical hysterectomy (RH). We retrospectively analyzed clinicopathologic data of 298 patients with FIGO stage IB cervical cancer treated by RH between February 2000 and March 2015. The nomogram was developed based on multivariate logistic regression analysis of preoperative clinicopathologic data. The accuracy and discriminative ability of the nomogram were evaluated by a concordance index and calibration curve. The low-risk group was predefined as having a predicted probability of PMI &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;10%. Multivariate analysis identified diameter-based tumor volume and disruption of the cervical stromal ring on magnetic resonance imaging, serum squamous cell carcinoma antigen level, and menopausal status as independent prognostic factors associated with PMI. The concordance index of the nomogram was 0.940 (95% CI, 0.908-0.967), and calibration plots revealed good agreement between the observed probabilities and nomogram-predicted probabilities (Hosmer Lemeshow test, p=0.574). The nomogram classified 200 out of 298 patients (67.1%) as low risk. In the low-risk group, the predicted probability of PMI was 3.5% and the actual PMI rate was 2.5% (5 out of 200). We developed a preoperative nomogram predicting microscopic PMI in surgically treated FIGO stage IB cervical cancer patients. The probabilities derived from this nomogram may have the potential to provide valuable guidance for physicians regarding the primary management of FIGO stage IB cervical cancer patients.

Scientific Reports, Aug 3, 2021

The precise prediction of acute kidney injury (AKI) after nephrectomy for renal cell carcinoma (R... more The precise prediction of acute kidney injury (AKI) after nephrectomy for renal cell carcinoma (RCC) is an important issue because of its relationship with subsequent kidney dysfunction and high mortality. Herein we addressed whether machine learning (ML) algorithms could predict postoperative AKI risk better than conventional logistic regression (LR) models. A total of 4104 RCC patients who had undergone unilateral nephrectomy from January 2003 to December 2017 were reviewed. ML models such as support vector machine, random forest, extreme gradient boosting, and light gradient boosting machine (LightGBM) were developed, and their performance based on the area under the receiver operating characteristic curve, accuracy, and F1 score was compared with that of the LR-based scoring model. Postoperative AKI developed in 1167 patients (28.4%). All the ML models had higher performance index values than the LR-based scoring model. Among them, the LightGBM model had the highest value of 0.810 (0.783-0.837). The decision curve analysis demonstrated a greater net benefit of the ML models than the LR-based scoring model over all the ranges of threshold probabilities. The application of ML algorithms improves the predictability of AKI after nephrectomy for RCC, and these models perform better than conventional LR-based models. Renal cell carcinoma (RCC) represents approximately 3% of cancers, and is the 3rd most common type of cancer in the genitourinary tract 1. During the last two decades, there has been an annual increase of 2% in its incidence worldwide 2. In particular, small RCCs with T1 stage account for more than half of the newly diagnosed cases 3. The early detection of small RCCs can improve overall survival of patients by curative nephrectomy 4. Along with this trend, the American and European guidelines recommend partial nephrectomy (PN) rather than radical nephrectomy (RN) for localized tumors in stage T1 as a curative approach 2,5. Despite an increasing tendency in performing PN, RN is also carried out, particularly in patients with chronic kidney disease, because of the high complication rate, long operation time, and potential morbidities of PN compared to RN 6-8. The worsening of postoperative renal function continues to be a great issue in patients who undergo nephrectomy for RCC because of their superior survival and large remnant functioning tissues. The loss of normal kidney tissues after PN or RN may result in an inevitable decline in kidney function despite the compensation of remnants 9-11. Compensatory hypertrophy and hyperfiltration of the remaining kidney occurs within hours after nephrectomy, and a subsequent decrease in glomerular filtration rates is transient or subclinical 12. However, 2-54% of patients experience postoperative acute kidney injury (AKI), which is attributable to several factors, such as elderly age, male sex, preoperative chronic kidney disease, diabetes mellitus, and RN 13-20. AKI after nephrectomy for RCC leaves sequelae in the remaining kidneys, which is a strong risk factor

Nephrology Dialysis Transplantation, Jun 1, 2023

Background and Aims: Compared to western countries, Korean CKD patients show distinctive differen... more Background and Aims: Compared to western countries, Korean CKD patients show distinctive differences in clinical outcomes including lower cardiovascular disease (CVD) and higher end-stage kidney disease (ESKD) events. This study analysed the risk factors, transition probability and cumulative hazards associated with clinical events using the multi-state model. Method: This study included 1423 patients at CKD stages 1-4 from KoreaN Cohort Study for Outcome in Patients With Chronic Kidney Disease. Multivariate multi-state model analysis was performed to investigate the risk factors, 10-year transition rate and cumulative hazard estimates for five clinical

Frontiers in Immunology, Mar 8, 2023

A Corrigendum on Elevated IFNA1 and suppressed IL12p40 associated with persistent hyperinflammati... more A Corrigendum on Elevated IFNA1 and suppressed IL12p40 associated with persistent hyperinflammation in COVID-19 pneumonia.

Frontiers in Immunology, Jan 27, 2023

Journal of Affective Disorders, Mar 1, 2023

Research Square (Research Square), Sep 20, 2021

Background and objectives The cause of chronic kidney disease (CKD) affects outcomes. However, re... more Background and objectives The cause of chronic kidney disease (CKD) affects outcomes. However, relative risks for adverse outcomes according to speci c causes of CKD are not well studied. Design, setting, participants and measurements Prospective cohort study from KNOW-CKD cohort were analyzed using overlap propensity score weighting methods. Patients were grouped into four categories according to the cause of CKD: glomerulonephritis (GN), diabetic nephropathy (DN), hypertensive nephropathy (HTN), or polycystic kidney disease (PKD). From a total of 2,070 patients, the relative risk of kidney failure, composite of cardiovascular disease (CVD) and mortality, and the slope of the estimated glomerular ltration rate (eGFR) decline according to the cause of CKD were compared between causative groups pairwisely. Results There were 565 cases of kidney failure and 259 cases of composite CVD and death over 6.0 years of followup. Hazard ratios of the PKD group for kidney failure were signi cantly increased at 1.82, 2.23, and 1.73 compared to GN, HTN, and DN, respectively. Hazard ratios of the DN group for the composite of CVD and death were also signi cantly increased at 2.07, and 1.73 compared to GN, and HTN, respectively. The adjusted eGFR decline slope for DN and PKD groups was-3.07, and-3.37 mL/min/1.73m 2 per year, respectively, and all of these values were signi cantly different than those of the GN and HTN groups (-2.16, and-1.42 mL/min/1.73m 2 per year, respectively). Conclusions Risks for renal progression were relatively higher in patients with PKD compared to other causes of CKD. However, the composite of CVD and death were relatively higher in patients with DN-related CKD than those with GN-and HTN-related CKD.

Journal of Hypertension, Oct 6, 2020

Objectives: Adequate blood pressure (BP) control is pivotal for managing chronic kidney disease (... more Objectives: Adequate blood pressure (BP) control is pivotal for managing chronic kidney disease (CKD). The optimal approach for monitoring BP to delay CKD progression is not yet clear. Methods: Patients with hypertension and CKD stage 3–4 were randomized into ambulatory blood pressure monitoring (ABPM) or office BP groups. All patients had ABPM at baseline and 18 months, and the ABPM group additionally underwent ABPM at 3 and 6 months. Each ABPM result was notified only for the ABPM group. The BP target was daytime ABP less than 135/85 mmHg for the ABPM group and office BP less than 140/90 mmHg for the office BP group. The primary outcome was decrease in estimated glomerular filtration rate (eGFR) during 18 months. Results: A total of 146 patients were randomized into the ABPM (n = 69) and office BP groups (n = 77). Although office BP was comparable in the two groups at baseline, daytime ABP was higher in the ABPM group (median 140 vs. 132 mmHg). Initial eGFR was 35.7 ± 12.5 ml/min per 1.73 m2 in the ABPM group and 34.6 ± 12.0 ml/min per 1.73 m2 in the office BP group. eGFR change was −5.5 [95% confidence interval (95% CI) −7.7 to −3.4] ml/min per 1.73 m2 in the ABPM group and −5.0 (95% CI −6.9 to −3.0) ml/min per 1.73 m2 in the office BP group (P = 0.704). Renal events occurred in 10 patients (15.6%) from the ABPM group and five (7.1%) from the office BP group (P = 0.120). Conclusion: The present study did not show a beneficial effect of ABPM for controlling hypertension in CKD compared with conventional office BP monitoring in terms of renal outcomes.

Scientific Reports, Apr 28, 2021

Acta Radiologica, Aug 6, 2018

Background: Aortic valve calcification quantification using cardiac computed tomography (CCT) is ... more Background: Aortic valve calcification quantification using cardiac computed tomography (CCT) is a reliable marker for aortic stenosis (AS) in patients with bicuspid aortic valve (BAV) disease. Purpose: To determine the association of Agatston aortic valve calcium score (AVCS) with morphological and hemodynamic characteristics of BAV and define cutoff AVCS for optimizing the grade of AS in patients with bicuspid AS. Material and Methods: This study included 161 BAV patients with AS regardless of aortic regurgitation who underwent transthoracic echocardiography and CCT. BAVs were classified according to orientation of cusps and presence of raphe. Associations of AVCS with characteristics of BAV morphology and functional variables were determined by linear regression analysis. Area under the receiver operating characteristic curve (AUC) was used to determine the cutoff AVCS greater than which the diagnosis of severe AS was optimized. Results: AVCS was significantly different according to sex (P < 0.001), AS severity (P < 0.001), type of valvular dysfunction (P ¼ 0.011), and orientation of cusps (P ¼ 0.028). Multiple linear regression showed that AVCS was significantly associated with sex (estimate ¼ À0.583, P < 0.001) and AS severity (estimate ¼ 0.817, P < 0.001). AVCS was a predictor for severe AS with AUC of 0.80 in both women (P ¼ 0.002) and men (P < 0.001). Its cutoff value was 1423 Agatston unit (AU) in women and 2573 AU in men. Conclusions: In patients with bicuspid AS, AVCS was significantly higher in men and those with severe AS. However, AVCS was not significantly associated with morphological characteristics of BAV or the type of valvular dysfunction.

Hpb, Apr 1, 2016

Background: Palliative resection of stage IV pancreatic ductal adenocarcinoma (PDAC) has not show... more Background: Palliative resection of stage IV pancreatic ductal adenocarcinoma (PDAC) has not shown its benefit until now. In our retrospective review, we compared the results of palliative resection to nonresection. Methods: Between 2000 and 2009, metastasis of PDAC was confirmed in the operating room in 150 patients. 35 underwent palliative resection (resection group; R) and 115 did bypass or biopsy. 35 patients (biopsy or bypass group: NR) in the 115 patients were matched with the patients undergoing resection for tumor size and the metastasis of peritoneal seeding. Demographic, clinical, operative data and survival were analyzed. Results: There was no significant difference of major complication (Clavien-Dindo classification 3-5) between two groups. There was no 30-day mortality in either group. More patients in R received postoperative chemotherapy (82.9% vs. 57.1%; P = 0.019). Multivariate analysis showed resection and postoperative chemotherapy as independent factor related to survival (hazard ratio, 0.44; 95% CI, 0.25-0.76; P = 0.003). Patients in R showed better survival rates compared to those in NR (P < 0.001). Conclusion: Our study suggests resection for stage IV PDAC can be associated with increased survival. In patients of stage IV PDAC, palliative resection with chemotherapy could have some benefit in selected patients.