1.National Trends in Influenza Vaccination Rates in South Korea Before and During the COVID-19 Pandemic, 2011-2022.
Kyeongeun KIM ; Kyeongmin LEE ; Yejun SON ; Seoyoung PARK ; Raphael UDEH ; Jiseung KANG ; Hayeon LEE ; Soeun KIM ; Jaeyu PARK ; Hyeon Jin KIM ; Damiano PIZZOL ; Lee SMITH ; Jiyoung HWANG ; Dong Keon YON
Biomedical and Environmental Sciences 2025;38(9):1044-1057
OBJECTIVE:
Despite the global decrease in influenza infections during the coronavirus disease 2019 (COVID-19) pandemic, seasonal influenza remains a significant health issue. South Korea, known for its robust pandemic response and high influenza vaccination rates, offers a unique context for examining changes in vaccination trends during the pandemic. Using nationally representative data, we aimed to understand the impact of the pandemic on influenza vaccination behavior over a 12-year period and to identify vulnerable groups.
METHODS:
We analyzed influenza vaccination rates in South Korea between 2011-2022, focusing on pandemic-related impacts. The data of 2,426,139 adults (≥ 19 years) from the Korea Community Health Survey were used to assess demographic and sociological factors influencing vaccination behaviors.
RESULTS:
We observed an increase in influenza vaccination rates during the pre-COVID-19 period from 2011-2013 (weighted prevalence: 46.68% [95% confidence interval ( CI): 46.55-46.82]) to 2017-2019 (weighted prevalence: 52.50% [95% CI: 52.38-52.63]). However, a significant decline was observed in 2022, the late-COVID-19 pandemic period (weighted prevalence: 55.78% [95% CI: 55.56-56.01]), compared with the mid-pandemic period in 2021 (weighted prevalence: 59.12% [95% CI: 58.91-59.32]), particularly among populations traditionally prioritized for influenza vaccination, including older adults (≥ 65 years) and patients with chronic diseases and low educational and income levels.
CONCLUSION
The influenza vaccination rate in South Korea was significantly affected by the COVID-19 pandemic, showing a notable decrease among vulnerable demographic groups. This suggests the need for targeted public health strategies to address vaccine hesitancy and improve vaccination rates, particularly among high-risk populations.
Humans
;
Republic of Korea/epidemiology*
;
COVID-19/epidemiology*
;
Adult
;
Middle Aged
;
Influenza Vaccines/administration & dosage*
;
Male
;
Female
;
Influenza, Human/epidemiology*
;
Aged
;
Vaccination/statistics & numerical data*
;
Young Adult
;
Pandemics
;
SARS-CoV-2
2.Closed intensive care units and sepsis patient outcomes: a secondary analysis of data from a multicenter prospective observational study in South Korea
Kyeongman JEON ; Jin Hyoung KIM ; Kyung Chan KIM ; Heung Bum LEE ; Hongyeul LEE ; Song I LEE ; Jin-Won HUH ; Won Gun KWACK ; Youjin CHANG ; Yun-Seong KANG ; Won Yeon LEE ; Je Hyeong KIM ;
Acute and Critical Care 2025;40(2):209-220
Background:
Sepsis is a leading cause of intensive care unit (ICU) admission. However, few studies have evaluated how the ICU model affects the outcomes of patients with sepsis.
Methods:
This post hoc analysis of data from the Management of Severe Sepsis in Asia’s Intensive Care Units II study included 537 patients with sepsis admitted to 27 ICUs in Korea. The outcome measures of interest were compared between the closed ICU group, patients admitted under the full responsibility of an intensivist as the primary attending physician, and the open ICU group. The association between a closed ICU and ICU mortality was evaluated using a logistic regression analysis.
Results:
Altogether, 363 and 174 enrolled patients were treated in open and closed ICUs, respectively. Compliance with the sepsis bundles did not differ between the two groups; however, the closed ICU group had a higher rate of renal replacement therapy and shorter duration of ventilator support. The closed ICU group also had a lower ICU mortality rate than the open ICU group (24.7% vs. 33.1%). In a logistic regression analysis, management in the closed ICU was significantly associated with a decreased ICU mortality rate even after adjusting for potential confounding factors (adjusted odds ratio, 0.576; 95% CI, 0.342–0.970), and that association was observed for up to 90 days.
Conclusions
Sepsis management in closed ICUs was significantly associated with improved ICU survival and decreased length of ICU stay, even though the compliance rates for the sepsis bundles did not differ between open and closed ICUs.
3.Updates of Evidence-Based Nursing Practice Guidelines for Peripheral Intravenous Infusion Therapy
Ihn Sook JEONG ; Chan Mi KANG ; Kyeong Sug KIM ; Hyun Lim KIM ; Jeong Ok PARK ; Joohyun LEE ; Kyung Choon LIM ; Go Eun CHOI
Journal of Korean Clinical Nursing Research 2025;31(1):1-14
Purpose:
This study was conducted to update the practice guidelines for intravenous infusion therapy published in 2017, focusing on the most recent evidence for peripheral intravenous infusion therapy.
Methods:
The guideline update was conducted using the 22-step methodology.
Results:
The updated guidelines consist of 17 domains and 235 recommendations (including 284 sub-recommendations). The domains are as follows: general instructions (5 items), peripheral catheter selection (7), catheter insertion site selection (11), management during peripheral catheter insertion (10), post-insertion management (30), perfusion and locking (17), blood sampling via peripheral catheters(6), exchange and removal of peripheral catheters (6), infusion set management (14), add-on devices (32), complications (25), chemotherapy infusions (10), PCA infusions (7), parenteral nutrition (20), transfusion therapy (23), education (5), and documentation and reporting (7). The evidence levels for these recommendations are as follows: 27(9.5%) at level I, 3 (1.1%) at level I A/P, 118 (41.5%) at level II, and 136 (47.9%) at level III.Recommendation grades are categorized as follows: 30 (10.6%) at level A, 118 (41.5%) at level B, and 136(47.9%) at level C. Of these, 73 (25.7%) recommendations were newly developed, 49 (17.3%) underwent major revisions, and 147 (51.7%) underwent minor revisions.
Conclusion
The updated practice guideline, based on the latest evidence, is anticipated to enhance nursing practice related to peripheral intravenous infusion therapy.
4.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.
5.Delayed Diagnosis of Imported Cystic Echinococcosis and Successful Treatment With Percutaneous Drainage and Albendazole in Korea: A Case Report
Won Jun CHOI ; Hanna JIN ; Hyeon Jae JO ; Chan Mi LEE ; Chang Kyung KANG ; Pyoeng Gyun CHOE ; Wan Beom PARK ; Nam Joong KIM ; Min-Ho CHOI
Journal of Korean Medical Science 2025;40(4):e88-
Echinococcosis, caused by the tapeworm Echinococcus, is rare in Korea and is primarily imported from endemic areas. We report a case of a 37-year-old Korean man with multiple large hepatic cysts, initially diagnosed as simple cysts at a local clinic in 2018. The patient had lived in Oman, an endemic area, for several months in 2016. Upon referral to a tertiary hospital in 2023, due to progressive cyst enlargement, liver magnetic resonance imaging revealed three large cysts with a water lily sign. Serum IgG against Echinococcus was positive by enzyme-linked immunosorbent assay. After diagnosis of echinococcosis, treatment with albendazole and puncture-aspiration-injection-reaspiration (PAIR) was performed.Microscopic and molecular analysis of cyst aspirates confirmed Echinococcus granulosus infection. Follow-up computed tomography demonstrated a reduction in cyst size, yet the emergence of a new right pleural effusion and consolidation in the left lower lobe of the lung necessitated the continuation of albendazole therapy. This case highlights the importance of thorough travel history, imaging findings, and the effectiveness of PAIR combined with albendazole in treating imported echinococcosis.
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.Non-Linear Association Between Physical Activities and Type 2Diabetes in 2.4 Million Korean Population, 2009–2022: A Nationwide Representative Study
Wonwoo JANG ; Seokjun KIM ; Yejun SON ; Soeun KIM ; Hayeon LEE ; Jaeyu PARK ; Kyeongmin LEE ; Jiseung KANG ; Damiano PIZZOL ; Jiyoung HWANG ; Sang Youl RHEE ; Dong Keon YON
Journal of Korean Medical Science 2025;40(12):e42-
Background:
Although excessive physical activity (PA) does not always confer additional health benefits, there is a paucity of studies that have quantitatively examined the doseresponse relationship between PA and type 2 diabetes. Therefore, this study investigated the relationship between the type 2 diabetes prevalence and intensity, frequency, and metabolic equivalent of task (MET) score of PA in a large population sample.
Methods:
We conducted a nationwide cross-sectional analysis examining sociodemographic variables, PA habits, and type 2 diabetes prevalence in 2,428,448 participants included in the Korea Community Health Survey. The non-linear association between MET score and odds ratios (ORs) for type 2 diabetes prevalence was plotted using a weighted generalized additive model. Categorical analysis was used to examine the joint association of moderate-intensity PA (MPA) and vigorous-intensity PA (VPA), and the influence of PA frequency.
Results:
MET score and diabetes prevalence revealed a non-linear association with the nadir at 1,028 MET-min/week, beyond which ORs increased with additional PA. Joint analysis of MPA and VPA showed the lowest OR of 0.79 (95% confidence interval, 0.75–0.84) for those engaging in 300–600 MET-min/week of MPA and > 600 MET-min/week of VPA concurrently, corresponding with World Health Organization recommendations. Additionally, both “weekend warriors” and “regularly active” individuals showed lower ORs compared to the inactive, although no significant difference was noted between the active groups.
Conclusion
In a large South Korean sample, higher PA is not always associated with a lower prevalence of type 2 diabetes, as the association follows a non-linear pattern; differences existed across sociodemographic variables. Considering the joint association, an adequate combination of MPA and VPA is recommended. The frequency of PA does not significantly influence the type 2 diabetes prevalence.
8.Constitutional Mismatch Repair Deficiency, the Most Aggressive Cancer Predisposition Syndrome : Clinical Presentation, Surveillance, and Management
Eungu KANG ; Jin Kyung SUH ; Sang-Dae KIM
Journal of Korean Neurosurgical Society 2025;68(3):294-304
Constitutional mismatch repair deficiency (CMMRD) is a rare and highly aggressive cancer predisposition syndrome caused by biallelic germline mutations in mismatch repair genes. This condition is characterized by early-onset malignancies across multiple organ systems, including central nervous system tumors, hematological cancers, and gastrointestinal malignancies. CMMRD-associated tumors exhibit hypermutation and microsatellite instability, resulting in a high tumor mutation burden and rendering these malignancies responsive to immune checkpoint inhibitors (ICIs). ICIs targeting programmed cell death protein-1 and programmed cell death ligand 1 have demonstrated remarkable efficacy, particularly in hypermutated tumors, providing durable responses and improving survival outcomes. Advances in genetic and molecular diagnostics have enhanced the ability to identify CMMRD early, allowing for the implementation of comprehensive surveillance programs and improved management strategies. A multidisciplinary and individualized approach is essential for managing CMMRD patients. This review underscores the importance of early diagnosis, surveillance, and emerging therapeutic approaches to improve outcomes and quality of life for individuals and families affected by this devastating syndrome.
9.Updates of Evidence-Based Nursing Practice Guidelines for Peripheral Intravenous Infusion Therapy
Ihn Sook JEONG ; Chan Mi KANG ; Kyeong Sug KIM ; Hyun Lim KIM ; Jeong Ok PARK ; Joohyun LEE ; Kyung Choon LIM ; Go Eun CHOI
Journal of Korean Clinical Nursing Research 2025;31(1):1-14
Purpose:
This study was conducted to update the practice guidelines for intravenous infusion therapy published in 2017, focusing on the most recent evidence for peripheral intravenous infusion therapy.
Methods:
The guideline update was conducted using the 22-step methodology.
Results:
The updated guidelines consist of 17 domains and 235 recommendations (including 284 sub-recommendations). The domains are as follows: general instructions (5 items), peripheral catheter selection (7), catheter insertion site selection (11), management during peripheral catheter insertion (10), post-insertion management (30), perfusion and locking (17), blood sampling via peripheral catheters(6), exchange and removal of peripheral catheters (6), infusion set management (14), add-on devices (32), complications (25), chemotherapy infusions (10), PCA infusions (7), parenteral nutrition (20), transfusion therapy (23), education (5), and documentation and reporting (7). The evidence levels for these recommendations are as follows: 27(9.5%) at level I, 3 (1.1%) at level I A/P, 118 (41.5%) at level II, and 136 (47.9%) at level III.Recommendation grades are categorized as follows: 30 (10.6%) at level A, 118 (41.5%) at level B, and 136(47.9%) at level C. Of these, 73 (25.7%) recommendations were newly developed, 49 (17.3%) underwent major revisions, and 147 (51.7%) underwent minor revisions.
Conclusion
The updated practice guideline, based on the latest evidence, is anticipated to enhance nursing practice related to peripheral intravenous infusion therapy.
10.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.

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