1.The Impact of COVID-19 on Admissions and In-hospital Mortality of Patients With Stroke in Korea: An Interrupted Time Series Analysis
Youngs CHANG ; Soo-Hee HWANG ; Haibin BAI ; Seowoo PARK ; Eunbyul CHO ; Dohoung KIM ; Hyejin LEE ; Jin Yong LEE
Journal of Preventive Medicine and Public Health 2025;58(1):60-71
Objectives:
This study aimed to investigate the impact of coronavirus disease 2019 (COVID-19) on admission rates and in-hospital mortality among patients with ischemic and hemorrhagic stroke.
Methods:
We constructed a dataset detailing the monthly hospitalizations and mortality rates of inpatients with stroke from January 2017 to December 2021. Employing an interrupted time series analysis, we explored the impact of COVID-19 on hospitalizations and 30-day in-hospital mortality among stroke patients.
Results:
The number of ischemic stroke admissions decreased by 18.5%, from 5335 to 4348, immediately following the COVID-19 outbreak (p<0.001). The in-hospital mortality rate for ischemic stroke increased slightly from 3.3% to 3.4% immediately after the outbreak, although it showed a decreasing trend over time. The number of hemorrhagic stroke admissions fell by 7.5%, from 2014 to 1864, immediately following the COVID-19 outbreak. The 30-day in-hospital mortality rate for hemorrhagic stroke initially decreased from 12.9% to 12.7%, but subsequently showed an increasing trend.
Conclusions
We confirmed that COVID-19 impacted both the admission and death rates of stroke patients. The admission rate for both ischemic and hemorrhagic strokes decreased, while in-hospital mortality increased. Specifically, in-hospital mortality from ischemic stroke rose initially after the outbreak before stabilizing. Additionally, our findings indicate variable effects based on sex, age, and socioeconomic status, suggesting that certain groups may be more susceptible. This underscores the need to identify and support vulnerable populations to mitigate adverse health outcomes.
2.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
3.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
4.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
5.The Impact of COVID-19 on Admissions and In-hospital Mortality of Patients With Stroke in Korea: An Interrupted Time Series Analysis
Youngs CHANG ; Soo-Hee HWANG ; Haibin BAI ; Seowoo PARK ; Eunbyul CHO ; Dohoung KIM ; Hyejin LEE ; Jin Yong LEE
Journal of Preventive Medicine and Public Health 2025;58(1):60-71
Objectives:
This study aimed to investigate the impact of coronavirus disease 2019 (COVID-19) on admission rates and in-hospital mortality among patients with ischemic and hemorrhagic stroke.
Methods:
We constructed a dataset detailing the monthly hospitalizations and mortality rates of inpatients with stroke from January 2017 to December 2021. Employing an interrupted time series analysis, we explored the impact of COVID-19 on hospitalizations and 30-day in-hospital mortality among stroke patients.
Results:
The number of ischemic stroke admissions decreased by 18.5%, from 5335 to 4348, immediately following the COVID-19 outbreak (p<0.001). The in-hospital mortality rate for ischemic stroke increased slightly from 3.3% to 3.4% immediately after the outbreak, although it showed a decreasing trend over time. The number of hemorrhagic stroke admissions fell by 7.5%, from 2014 to 1864, immediately following the COVID-19 outbreak. The 30-day in-hospital mortality rate for hemorrhagic stroke initially decreased from 12.9% to 12.7%, but subsequently showed an increasing trend.
Conclusions
We confirmed that COVID-19 impacted both the admission and death rates of stroke patients. The admission rate for both ischemic and hemorrhagic strokes decreased, while in-hospital mortality increased. Specifically, in-hospital mortality from ischemic stroke rose initially after the outbreak before stabilizing. Additionally, our findings indicate variable effects based on sex, age, and socioeconomic status, suggesting that certain groups may be more susceptible. This underscores the need to identify and support vulnerable populations to mitigate adverse health outcomes.
6.Gaps and Similarities in Research Use LOINC Codes Utilized in Korean University Hospitals: Towards Semantic Interoperability for Patient Care
Kuenyoul PARK ; Min-Sun KIM ; YeJin OH ; John Hoon RIM ; Shinae YU ; Hyejin RYU ; Eun-Jung CHO ; Kyunghoon LEE ; Ha Nui KIM ; Inha CHUN ; AeKyung KWON ; Sollip KIM ; Jae-Woo CHUNG ; Hyojin CHAE ; Ji Seon OH ; Hyung-Doo PARK ; Mira KANG ; Yeo-Min YUN ; Jong-Baeck LIM ; Young Kyung LEE ; Sail CHUN
Journal of Korean Medical Science 2025;40(1):e4-
Background:
The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings.
Methods:
We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes.
Results:
A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%).
Conclusion
This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.
7.The Impact of COVID-19 on Admissions and In-hospital Mortality of Patients With Stroke in Korea: An Interrupted Time Series Analysis
Youngs CHANG ; Soo-Hee HWANG ; Haibin BAI ; Seowoo PARK ; Eunbyul CHO ; Dohoung KIM ; Hyejin LEE ; Jin Yong LEE
Journal of Preventive Medicine and Public Health 2025;58(1):60-71
Objectives:
This study aimed to investigate the impact of coronavirus disease 2019 (COVID-19) on admission rates and in-hospital mortality among patients with ischemic and hemorrhagic stroke.
Methods:
We constructed a dataset detailing the monthly hospitalizations and mortality rates of inpatients with stroke from January 2017 to December 2021. Employing an interrupted time series analysis, we explored the impact of COVID-19 on hospitalizations and 30-day in-hospital mortality among stroke patients.
Results:
The number of ischemic stroke admissions decreased by 18.5%, from 5335 to 4348, immediately following the COVID-19 outbreak (p<0.001). The in-hospital mortality rate for ischemic stroke increased slightly from 3.3% to 3.4% immediately after the outbreak, although it showed a decreasing trend over time. The number of hemorrhagic stroke admissions fell by 7.5%, from 2014 to 1864, immediately following the COVID-19 outbreak. The 30-day in-hospital mortality rate for hemorrhagic stroke initially decreased from 12.9% to 12.7%, but subsequently showed an increasing trend.
Conclusions
We confirmed that COVID-19 impacted both the admission and death rates of stroke patients. The admission rate for both ischemic and hemorrhagic strokes decreased, while in-hospital mortality increased. Specifically, in-hospital mortality from ischemic stroke rose initially after the outbreak before stabilizing. Additionally, our findings indicate variable effects based on sex, age, and socioeconomic status, suggesting that certain groups may be more susceptible. This underscores the need to identify and support vulnerable populations to mitigate adverse health outcomes.
8.An Artificial Intelligence-Based Automated Echocardiographic Analysis: Enhancing Efficiency and Prognostic Evaluation in Patients With Revascularized STEMI
Yeonggul JANG ; Hyejung CHOI ; Yeonyee E. YOON ; Jaeik JEON ; Hyejin KIM ; Jiyeon KIM ; Dawun JEONG ; Seongmin HA ; Youngtaek HONG ; Seung-Ah LEE ; Jiesuck PARK ; Wonsuk CHOI ; Hong-Mi CHOI ; In-Chang HWANG ; Goo-Yeong CHO ; Hyuk-Jae CHANG
Korean Circulation Journal 2024;54(11):743-756
Background and Objectives:
Although various cardiac parameters on echocardiography have clinical importance, their measurement by conventional manual methods is time-consuming and subject to variability. We evaluated the feasibility, accuracy, and predictive value of an artificial intelligence (AI)-based automated system for echocardiographic analysis in patients with ST-segment elevation myocardial infarction (STEMI).
Methods:
The AI-based system was developed using a nationwide echocardiographic dataset from five tertiary hospitals, and automatically identified views, then segmented and tracked the left ventricle (LV) and left atrium (LA) to produce volume and strain values. Both conventional manual measurements and AI-based fully automated measurements of the LV ejection fraction and global longitudinal strain, and LA volume index and reservoir strain were performed in 632 patients with STEMI.
Results:
The AI-based system accurately identified necessary views (overall accuracy, 98.5%) and successfully measured LV and LA volumes and strains in all cases in which conventional methods were applicable. Inter-method analysis showed strong correlations between measurement methods, with Pearson coefficients ranging 0.81–0.92 and intraclass correlation coefficients ranging 0.74–0.90. For the prediction of clinical outcomes (composite of all-cause death, re-hospitalization due to heart failure, ventricular arrhythmia, and recurrent myocardial infarction), AI-derived measurements showed predictive value independent of clinical risk factors, comparable to those from conventional manual measurements.
Conclusions
Our fully automated AI-based approach for LV and LA analysis on echocardiography is feasible and provides accurate measurements, comparable to conventional methods, in patients with STEMI, offering a promising solution for comprehensive echocardiographic analysis, reduced workloads, and improved patient care.
9.Effects of the COVID-19 Pandemic on the Medical Use of Elderly Patients with Hypertension: A Nationwide Cohort Study in Korea
Eunbyul CHO ; Sujeong HAN ; Jae-ryun LEE ; Hyejin LEE ; Bumjo OH
Korean Journal of Family Medicine 2024;45(5):283-289
Background:
The coronavirus disease 2019 (COVID-19) pandemic has disrupted healthcare services, including chronic disease management, for vulnerable groups, such as older individuals with hypertension. This study aimed to evaluate hypertension management in South Korea’s elderly population during the pandemic using treatment consistency indices such as the continuity of care (COC), modified, modified continuity index (MMCI), and most frequent provider continuity (MFPC).
Methods:
This study used the Korea Disease Control and Prevention Agency-COVID-19-National Health Insurance Service cohort (K-COV-N cohort) from the National Health Insurance Service between 2017 and 2021. The research included a total of 4,097,299 hypertensive patients aged 65 years or older. We defined 2018 and 2019 as the baseline period before the COVID-19 pandemic and 2020 and 2021 as the COVID-19 period and calculated the indices of medical continuity (number of visits, COC, MMCI, and MFPC) on a yearly basis.
Results:
The number of visits decreased during the COVID-19 period compared to the baseline period (59.64±52.75 vs. 50.49±50.33, P<0.001). However, COC, MMCI, and MFPC were not decreased in the baseline period compared to the COVID-19 period (0.71±0.21 vs. 0.71±0.22, P<0.001; 0.97±0.05 vs. 0.96±0.05, P<0.001; 0.8±0.17 vs. 0.8±0.17, P<0.001, respectively).
Conclusion
COVID-19 had no significant impact on the continuity of care but affected the frequency of outpatient visits for older patients with hypertension. However, this study highlights the importance of addressing healthcare inequalities, especially in older patients with hypertension, during pandemics and advocates for policy changes to ensure continued care for vulnerable populations.
10.An Artificial Intelligence-Based Automated Echocardiographic Analysis: Enhancing Efficiency and Prognostic Evaluation in Patients With Revascularized STEMI
Yeonggul JANG ; Hyejung CHOI ; Yeonyee E. YOON ; Jaeik JEON ; Hyejin KIM ; Jiyeon KIM ; Dawun JEONG ; Seongmin HA ; Youngtaek HONG ; Seung-Ah LEE ; Jiesuck PARK ; Wonsuk CHOI ; Hong-Mi CHOI ; In-Chang HWANG ; Goo-Yeong CHO ; Hyuk-Jae CHANG
Korean Circulation Journal 2024;54(11):743-756
Background and Objectives:
Although various cardiac parameters on echocardiography have clinical importance, their measurement by conventional manual methods is time-consuming and subject to variability. We evaluated the feasibility, accuracy, and predictive value of an artificial intelligence (AI)-based automated system for echocardiographic analysis in patients with ST-segment elevation myocardial infarction (STEMI).
Methods:
The AI-based system was developed using a nationwide echocardiographic dataset from five tertiary hospitals, and automatically identified views, then segmented and tracked the left ventricle (LV) and left atrium (LA) to produce volume and strain values. Both conventional manual measurements and AI-based fully automated measurements of the LV ejection fraction and global longitudinal strain, and LA volume index and reservoir strain were performed in 632 patients with STEMI.
Results:
The AI-based system accurately identified necessary views (overall accuracy, 98.5%) and successfully measured LV and LA volumes and strains in all cases in which conventional methods were applicable. Inter-method analysis showed strong correlations between measurement methods, with Pearson coefficients ranging 0.81–0.92 and intraclass correlation coefficients ranging 0.74–0.90. For the prediction of clinical outcomes (composite of all-cause death, re-hospitalization due to heart failure, ventricular arrhythmia, and recurrent myocardial infarction), AI-derived measurements showed predictive value independent of clinical risk factors, comparable to those from conventional manual measurements.
Conclusions
Our fully automated AI-based approach for LV and LA analysis on echocardiography is feasible and provides accurate measurements, comparable to conventional methods, in patients with STEMI, offering a promising solution for comprehensive echocardiographic analysis, reduced workloads, and improved patient care.

Result Analysis
Print
Save
E-mail