1.Initial and peak serum levels of Krebs von den Lungen-6 for predicting the prognosis of patients with COVID-19
Geonui KIM ; Hyeonwoo KWON ; Sang Hyun RA ; Euijin CHANG ; Seongman BAE ; Jiwon JUNG ; Min Jae KIM ; Yong Pil CHONG ; Sang-Oh LEE ; Sang-Ho CHOI ; Yang Soo KIM ; Sung-Han KIM
The Korean Journal of Internal Medicine 2025;40(2):321-329
Background/Aims:
Krebs von den Lungen-6 (KL-6) is associated with prognosis in patients with COVID-19. However, there is limited data on the correlation between the prognosis of COVID-19 and varying KL-6 levels at different time points. We investigated the optimal cutoff values of the initial and peak serum KL-6 levels to predict mortality and evaluated their correlation with mortality.
Methods:
This retrospective cohort study collected data on serially collected serum KL-6 levels in patients hospitalized with COVID-19 between October 2020 and January 2022 at a single tertiary hospital in South Korea. The area under the receiver operating characteristic curve and Youden index were used to determine the cutoff points for the initial and peak KL-6 levels that best predicted 30-day mortality. The association between the initial and peak KL-6 values was assessed by univariate and multivariate logistic regression models.
Results:
A total of 349 patients were included in this study. The mean initial and peak KL-6 levels were significantly higher in the non-survivor group than in the survivor group. The initial and peak KL-6 values that best predicted 30-day mortality were 491.85 U/mL and 660.05 U/mL, respectively. An initial KL-6 level greater than 491.85 U/mL and a peak KL-6 level greater than 660.05 U/mL were significantly associated with 30-day mortality.
Conclusions
The initial and peak levels of KL-6 were significantly associated with 30-day mortality in hospitalized patients with COVID-19. These findings suggest that serially monitoring blood KL-6 levels could be a valuable prognostic indicator for COVID-19.
2.Initial and peak serum levels of Krebs von den Lungen-6 for predicting the prognosis of patients with COVID-19
Geonui KIM ; Hyeonwoo KWON ; Sang Hyun RA ; Euijin CHANG ; Seongman BAE ; Jiwon JUNG ; Min Jae KIM ; Yong Pil CHONG ; Sang-Oh LEE ; Sang-Ho CHOI ; Yang Soo KIM ; Sung-Han KIM
The Korean Journal of Internal Medicine 2025;40(2):321-329
Background/Aims:
Krebs von den Lungen-6 (KL-6) is associated with prognosis in patients with COVID-19. However, there is limited data on the correlation between the prognosis of COVID-19 and varying KL-6 levels at different time points. We investigated the optimal cutoff values of the initial and peak serum KL-6 levels to predict mortality and evaluated their correlation with mortality.
Methods:
This retrospective cohort study collected data on serially collected serum KL-6 levels in patients hospitalized with COVID-19 between October 2020 and January 2022 at a single tertiary hospital in South Korea. The area under the receiver operating characteristic curve and Youden index were used to determine the cutoff points for the initial and peak KL-6 levels that best predicted 30-day mortality. The association between the initial and peak KL-6 values was assessed by univariate and multivariate logistic regression models.
Results:
A total of 349 patients were included in this study. The mean initial and peak KL-6 levels were significantly higher in the non-survivor group than in the survivor group. The initial and peak KL-6 values that best predicted 30-day mortality were 491.85 U/mL and 660.05 U/mL, respectively. An initial KL-6 level greater than 491.85 U/mL and a peak KL-6 level greater than 660.05 U/mL were significantly associated with 30-day mortality.
Conclusions
The initial and peak levels of KL-6 were significantly associated with 30-day mortality in hospitalized patients with COVID-19. These findings suggest that serially monitoring blood KL-6 levels could be a valuable prognostic indicator for COVID-19.
3.Association of Age, Sex and Education With Access to the Intravenous Thrombolysis for Acute Ischemic Stroke
Yoona KO ; Beom Joon KIM ; Youngran KIM ; Jong-Moo PARK ; Kyusik KANG ; Jae Guk KIM ; Jae-Kwan CHA ; Tai Hwan PARK ; Kyungbok LEE ; Jun LEE ; Keun-Sik HONG ; Byung-Chul LEE ; Kyung-Ho YU ; Dong-Eog KIM ; Joon-Tae KIM ; Jay Chol CHOI ; Jee Hyun KWON ; Wook-Joo KIM ; Kyu Sun YUM ; Sung-Il SOHN ; Hyungjong PARK ; Sang-Hwa LEE ; Kwang-Yeol PARK ; Chi Kyung KIM ; Sung Hyuk HEO ; Moon-Ku HAN ; Anjail Z. SHARRIEF ; Sunil A. SHETH ; Hee-Joon BAE ;
Journal of Korean Medical Science 2025;40(13):e49-
Background:
Barriers to treatment with intravenous thrombolysis (IVT) for patients with acute ischemic stroke (AIS) in South Korea remain incompletely characterized. We analyze a nationwide prospective cohort to determine patient-level features associated with delayed presentation and non-treatment of potential IVT-eligible patients.
Methods:
We identified consecutive patients with AIS from 01/2011 to 08/2023 from a multicenter and prospective acute stroke registry in Korea. Patients were defined as IVT candidates if they presented within 4.5 hours from the last known well, had no lab evidence of coagulopathy, and had National Institute of Health Stroke Scale (NIHSS) ≥ 4. Multivariable generalized linear mixed regression models were used to investigate the associations between their characteristics and the IVT candidates or the use of IVT among the candidates.
Results:
Among 84,103 AIS patients, 41.0% were female, with a mean age of 69 ± 13 years and presentation NIHSS of 4 [interquartile range, 1–8]. Out of these patients, 13,757 (16.4%) were eligible for IVT, of whom 8,179 (59.5%) received IVT. Female sex (adjusted risk ratio [RR], 0.90; 95% confidence interval [CI], 0.86–0.94) and lower years of education (adjusted RR, 0.90; 95% CI, 0.84–0.97 for 0–3 years, compared to ≥ 13 years) were associated with a decreased likelihood of presenting as eligible for IVT after AIS; meanwhile, young age (adjusted RR, 1.12; 95% CI, 1.01–1.24 for ≤ 44 years, compared to 75–84 years) was associated with an increased likelihood of being an IVT candidate. Among those who were eligible for IVT, only age was significantly associated with the use of IVT (adjusted RR, 1.09; 95% CI, 1.03–1.16 for age 65–74 and adjusted RR, 0.83; 95% CI, 0.76–0.90 for ≥ 85 years, respectively).
Conclusion
Most patients with AIS present outside IVT eligibility in South Korea, and only 60% of eligible patients were ultimately treated. We identified increased age, female sex and lower education as key features on which to focus interventions for improving IVT utilization.
4.A Study on the Healthcare Workforce and Care for Acute Stroke: Results From the Survey of Hospitals Included in the National Acute Stroke Quality Assessment Program
Jong Young LEE ; Jun Kyeong KO ; Hak Cheol KO ; Hae-Won KOO ; Hyon-Jo KWON ; Dae-Won KIM ; Kangmin KIM ; Myeong Jin KIM ; Hoon KIM ; Keun Young PARK ; Kuhyun YANG ; Jae Sang OH ; Won Ki YOON ; Dong Hoon LEE ; Ho Jun YI ; Heui Seung LEE ; Jong-Kook RHIM ; Dong-Kyu JANG ; Youngjin JUNG ; Sang Woo HA ; Seung Hun SHEEN
Journal of Korean Medical Science 2025;40(16):e44-
Background:
With growing elderly populations, management of patients with acute stroke is increasingly important. In South Korea, the Acute Stroke Quality Assessment Program (ASQAP) has contributed to improving the quality of stroke care and practice behavior in healthcare institutions. While the mortality of hemorrhagic stroke remains high, there are only a few assessment indices associated with hemorrhagic stroke. Considering the need to develop assessment indices to improve the actual quality of care in the field of acute stroke treatment, this study aims to investigate the current status of human resources and practices related to the treatment of patients with acute stroke through a nationwide survey.
Methods:
For the healthcare institutions included in the Ninth ASQAP of the Health Insurance Review and Assessment Service (HIRA), data from January 2022 to December 2022 were collected through a survey on the current status and practice of healthcare providers related to the treatment of patients with acute stroke. The questionnaire consisted of 19 items, including six items on healthcare providers involved in stroke care and 10 items on the care of patients with acute stroke.
Results:
In the treatment of patients with hemorrhagic stroke among patients with acute stroke, neurosurgeons were the most common providers. The contribution of neurosurgeons in the treatment of ischemic stroke has also been found to be equivalent to that of neurologists. However, a number of institutions were found to be devoid of healthcare providers who perform definitive treatments, such as intra-arterial thrombectomy for patients with ischemic stroke or cerebral aneurysm clipping for subarachnoid hemorrhage. The intensity of the workload of healthcare providers involved in the care of patients with acute stroke, especially those involved in definitive treatment, was also found to be quite high.
Conclusion
Currently, there are almost no assessment indices specific to hemorrhagic stroke in the ASQAP for acute stroke. Furthermore, it does not reflect the reality of the healthcare providers and practices that provide definitive treatment for acute stroke. The findings of this study suggest the need for the development of appropriate assessment indices that reflect the realities of acute stroke care.
5.Epidemiology and Functional Outcome of Acute Stroke Patients in Korea Using Nationwide data
Seungmin SHIN ; Young Woo KIM ; Seung Hun SHEEN ; Sukh Que PARK ; Sung-Chul JIN ; Jin Pyeong JEON ; Ji Young LEE ; Boung Chul LEE ; Young Wha LIM ; Gui Ok KIM ; Youg Uk KWON ; Yu Ra LEE ; So Young HAN ; Jae Sang OH
Journal of Korean Neurosurgical Society 2025;68(2):159-176
Objective:
: Korea’s healthcare system and policy promotes early, actively stroke treatment to improve prognosis. This study represents stroke epidemiology and outcomes in Korea.
Methods:
: This study investigated data from the Acute Stroke Assessment Registry. The registry collects data from over 220 hospitals nationwide, focusing on quality stroke service management. Data analysis included patient demographics, stroke severity assessment, and discharge prognosis measurement using standardized scales.
Results:
: Eighty-six thousand five hundred sixty-eight acute stroke patients were collected with demographic and clinical characteristics during 18 months from 2016, 2018, and between 2020 to 2021, focusing on acute subarachnoid hemorrhage (SAH), acute intracerebral hemorrhage (ICH), and acute ischemic stroke. Of these 86568 patients, 8.3% was SAH, 16.3% ICH, and 74.9% ischemic stroke. Trends showed decreasing SAH and increasing ICH cases over the years. 68.3% stroke patients had the clear onset time. 49.6% stroke patients arrived within 4.5 hours of symptom onset, with more patients treated at general hospitals. Good functional outcomes at discharge was obtained with 58.3% of acute stroke patients, 55.9% of SAH patients, 34.6% of ICH patients, and 63.8% of ischemic stroke patients.
Conclusion
: The results showed that ischemic stroke was the most common subtype, followed by ICH and SAH. Prognosis differed among subtypes, with favorable outcomes more common in ischemic stroke and SAH compared to ICH.
6.Association of Age, Sex and Education With Access to the Intravenous Thrombolysis for Acute Ischemic Stroke
Yoona KO ; Beom Joon KIM ; Youngran KIM ; Jong-Moo PARK ; Kyusik KANG ; Jae Guk KIM ; Jae-Kwan CHA ; Tai Hwan PARK ; Kyungbok LEE ; Jun LEE ; Keun-Sik HONG ; Byung-Chul LEE ; Kyung-Ho YU ; Dong-Eog KIM ; Joon-Tae KIM ; Jay Chol CHOI ; Jee Hyun KWON ; Wook-Joo KIM ; Kyu Sun YUM ; Sung-Il SOHN ; Hyungjong PARK ; Sang-Hwa LEE ; Kwang-Yeol PARK ; Chi Kyung KIM ; Sung Hyuk HEO ; Moon-Ku HAN ; Anjail Z. SHARRIEF ; Sunil A. SHETH ; Hee-Joon BAE ;
Journal of Korean Medical Science 2025;40(13):e49-
Background:
Barriers to treatment with intravenous thrombolysis (IVT) for patients with acute ischemic stroke (AIS) in South Korea remain incompletely characterized. We analyze a nationwide prospective cohort to determine patient-level features associated with delayed presentation and non-treatment of potential IVT-eligible patients.
Methods:
We identified consecutive patients with AIS from 01/2011 to 08/2023 from a multicenter and prospective acute stroke registry in Korea. Patients were defined as IVT candidates if they presented within 4.5 hours from the last known well, had no lab evidence of coagulopathy, and had National Institute of Health Stroke Scale (NIHSS) ≥ 4. Multivariable generalized linear mixed regression models were used to investigate the associations between their characteristics and the IVT candidates or the use of IVT among the candidates.
Results:
Among 84,103 AIS patients, 41.0% were female, with a mean age of 69 ± 13 years and presentation NIHSS of 4 [interquartile range, 1–8]. Out of these patients, 13,757 (16.4%) were eligible for IVT, of whom 8,179 (59.5%) received IVT. Female sex (adjusted risk ratio [RR], 0.90; 95% confidence interval [CI], 0.86–0.94) and lower years of education (adjusted RR, 0.90; 95% CI, 0.84–0.97 for 0–3 years, compared to ≥ 13 years) were associated with a decreased likelihood of presenting as eligible for IVT after AIS; meanwhile, young age (adjusted RR, 1.12; 95% CI, 1.01–1.24 for ≤ 44 years, compared to 75–84 years) was associated with an increased likelihood of being an IVT candidate. Among those who were eligible for IVT, only age was significantly associated with the use of IVT (adjusted RR, 1.09; 95% CI, 1.03–1.16 for age 65–74 and adjusted RR, 0.83; 95% CI, 0.76–0.90 for ≥ 85 years, respectively).
Conclusion
Most patients with AIS present outside IVT eligibility in South Korea, and only 60% of eligible patients were ultimately treated. We identified increased age, female sex and lower education as key features on which to focus interventions for improving IVT utilization.
7.A Study on the Healthcare Workforce and Care for Acute Stroke: Results From the Survey of Hospitals Included in the National Acute Stroke Quality Assessment Program
Jong Young LEE ; Jun Kyeong KO ; Hak Cheol KO ; Hae-Won KOO ; Hyon-Jo KWON ; Dae-Won KIM ; Kangmin KIM ; Myeong Jin KIM ; Hoon KIM ; Keun Young PARK ; Kuhyun YANG ; Jae Sang OH ; Won Ki YOON ; Dong Hoon LEE ; Ho Jun YI ; Heui Seung LEE ; Jong-Kook RHIM ; Dong-Kyu JANG ; Youngjin JUNG ; Sang Woo HA ; Seung Hun SHEEN
Journal of Korean Medical Science 2025;40(16):e44-
Background:
With growing elderly populations, management of patients with acute stroke is increasingly important. In South Korea, the Acute Stroke Quality Assessment Program (ASQAP) has contributed to improving the quality of stroke care and practice behavior in healthcare institutions. While the mortality of hemorrhagic stroke remains high, there are only a few assessment indices associated with hemorrhagic stroke. Considering the need to develop assessment indices to improve the actual quality of care in the field of acute stroke treatment, this study aims to investigate the current status of human resources and practices related to the treatment of patients with acute stroke through a nationwide survey.
Methods:
For the healthcare institutions included in the Ninth ASQAP of the Health Insurance Review and Assessment Service (HIRA), data from January 2022 to December 2022 were collected through a survey on the current status and practice of healthcare providers related to the treatment of patients with acute stroke. The questionnaire consisted of 19 items, including six items on healthcare providers involved in stroke care and 10 items on the care of patients with acute stroke.
Results:
In the treatment of patients with hemorrhagic stroke among patients with acute stroke, neurosurgeons were the most common providers. The contribution of neurosurgeons in the treatment of ischemic stroke has also been found to be equivalent to that of neurologists. However, a number of institutions were found to be devoid of healthcare providers who perform definitive treatments, such as intra-arterial thrombectomy for patients with ischemic stroke or cerebral aneurysm clipping for subarachnoid hemorrhage. The intensity of the workload of healthcare providers involved in the care of patients with acute stroke, especially those involved in definitive treatment, was also found to be quite high.
Conclusion
Currently, there are almost no assessment indices specific to hemorrhagic stroke in the ASQAP for acute stroke. Furthermore, it does not reflect the reality of the healthcare providers and practices that provide definitive treatment for acute stroke. The findings of this study suggest the need for the development of appropriate assessment indices that reflect the realities of acute stroke care.
8.Epidemiology and Functional Outcome of Acute Stroke Patients in Korea Using Nationwide data
Seungmin SHIN ; Young Woo KIM ; Seung Hun SHEEN ; Sukh Que PARK ; Sung-Chul JIN ; Jin Pyeong JEON ; Ji Young LEE ; Boung Chul LEE ; Young Wha LIM ; Gui Ok KIM ; Youg Uk KWON ; Yu Ra LEE ; So Young HAN ; Jae Sang OH
Journal of Korean Neurosurgical Society 2025;68(2):159-176
Objective:
: Korea’s healthcare system and policy promotes early, actively stroke treatment to improve prognosis. This study represents stroke epidemiology and outcomes in Korea.
Methods:
: This study investigated data from the Acute Stroke Assessment Registry. The registry collects data from over 220 hospitals nationwide, focusing on quality stroke service management. Data analysis included patient demographics, stroke severity assessment, and discharge prognosis measurement using standardized scales.
Results:
: Eighty-six thousand five hundred sixty-eight acute stroke patients were collected with demographic and clinical characteristics during 18 months from 2016, 2018, and between 2020 to 2021, focusing on acute subarachnoid hemorrhage (SAH), acute intracerebral hemorrhage (ICH), and acute ischemic stroke. Of these 86568 patients, 8.3% was SAH, 16.3% ICH, and 74.9% ischemic stroke. Trends showed decreasing SAH and increasing ICH cases over the years. 68.3% stroke patients had the clear onset time. 49.6% stroke patients arrived within 4.5 hours of symptom onset, with more patients treated at general hospitals. Good functional outcomes at discharge was obtained with 58.3% of acute stroke patients, 55.9% of SAH patients, 34.6% of ICH patients, and 63.8% of ischemic stroke patients.
Conclusion
: The results showed that ischemic stroke was the most common subtype, followed by ICH and SAH. Prognosis differed among subtypes, with favorable outcomes more common in ischemic stroke and SAH compared to ICH.
9.PDK4 expression and tumor aggressiveness in prostate cancer
Eun Hye LEE ; Yun-Sok HA ; Bo Hyun YOON ; Minji JEON ; Dong Jin PARK ; Jiyeon KIM ; Jun-Koo KANG ; Jae-Wook CHUNG ; Bum Soo KIM ; Seock Hwan CHOI ; Hyun Tae KIM ; Tae-Hwan KIM ; Eun Sang YOO ; Tae Gyun KWON
Investigative and Clinical Urology 2025;66(3):227-235
Purpose:
Prostate cancer ranks as the second most common cancer in men globally, representing a significant cause of cancer-related mortality. Metastasis, the spread of cancer cells from the primary site to distant organs, remains a major challenge in managing prostate cancer. Pyruvate dehydrogenase kinase 4 (PDK4) is implicated in the regulation of aerobic glycolysis, emerging as a potential player in various cancers. However, its role in prostate cancer remains unclear. This study aims to analyze PDK4 expression in prostate cancer cells and human samples, and to explore the gene's clinical significance.
Materials and Methods:
PDK4 expression was detected in cell lines and human tissue samples. Migration ability was analyzed using Matrigel-coated invasion chambers. Human samples were obtained from the Kyungpook National University Chilgok Hospital.
Results:
PDK4 expression was elevated in prostate cancer cell lines compared to normal prostate cells, with particularly high levels in DU145 and LnCap cell lines. PDK4 knockdown in these cell lines suppressed their invasion ability, indicating a potential role of PDK4 in prostate cancer metastasis. Furthermore, our results revealed alterations in epithelial-mesenchymal transition markers and downstream signaling molecules following PDK4 suppression, suggesting its involvement in the modulation of invasion-related pathways. Furthermore, PDK4 expression was increased in prostate cancer tissues, especially in castration-resistant prostate cancer, compared to normal prostate tissues, with PSA and PDK4 expression showing a significantly positive correlation.
Conclusions
PDK4 expression in prostate cancer is associated with tumor invasion and castration status. Further validation is needed to demonstrate its effectiveness as a therapeutic target.
10.Plasma C-Peptide Levels and the Continuous Glucose Monitoring-Defined Coefficient of Variation in Risk Prediction for Hypoglycemia in Korean People with Diabetes Having Normal and Impaired Kidney Function
So Yoon KWON ; Jiyun PARK ; So Hee PARK ; You-Bin LEE ; Gyuri KIM ; Kyu Yeon HUR ; Jae Hyeon KIM ; Sang-Man JIN
Endocrinology and Metabolism 2025;40(2):268-277
Background:
We aimed to investigate the predictive values of plasma C-peptide levels and the continuous glucose monitoring (CGM)-defined coefficient of variation (CV) in risk prediction for hypoglycemia in Korean people with diabetes with normal and impaired kidney function.
Methods:
We analyzed data from 1,185 participants diagnosed with type 1 and type 2 diabetes who underwent blinded professional CGM between January 2009 and May 2021 at outpatient clinics. We explored correlations among CGM-defined CV, plasma C-peptide levels, and time below range at <70 and 54 mg/dL across different kidney function categories.
Results:
In patients with chronic kidney disease (CKD) stages 1–2 (n=934), 89.3% who had a random plasma C-peptide level higher than 600 pmol/L exhibited a CV of ≤36%. Among those in CKD stage 3 (n=161) with a random plasma C-peptide level exceeding 600 pmol/L, 66.7% showed a CV of ≤36%. In stages 4–5 of CKD (n=90), the correlation between random C-peptide levels and CV was not significant (r=–0.05, P=0.640), including cases with a CV greater than 36% despite very high random plasma C-peptide levels. Random plasma C-peptide levels and CGM-assessed CV significantly predicted hypoglycemia in CKD stages 1–2 and 1–5, respectively.
Conclusion
The established C-peptide criteria in Western populations are applicable to Korean people with diabetes for hypoglycemic risk prediction, unless kidney function is impaired equivalent to CKD stage 3–5. The CGM-defined CV is informative for hypoglycemic risk prediction regardless of kidney function.

Result Analysis
Print
Save
E-mail