1.Part 1. Current Status of Hearing Loss Patients in Korea Using National Data: National Health Insurance Service- Database, 2010 to 2020
Junhun LEE ; Chul Young YOON ; Jiwon KIM ; In-Ki JIN ; Michelle J. SUH ; Wan-Ho CHO ; Hyo-Jeong LEE ; Seong Jun CHOI ; Dongchul CHA ; Kyung Ho PARK ; Soo Hee OH ; Young Joon SEO ; Tae Hoon KONG
Korean Journal of Otolaryngology - Head and Neck Surgery 2025;68(1):7-18
Background and Objectives:
Hearing loss significantly affects communication, psychosocial well-being, and quality of life. This study analyzes the National Health Insurance Service database to assess the trends and characteristics of hearing loss in South Korea from 2010 to 2020.Subjects and Method The database encompasses 97% of the Korean population, providing comprehensive data on medical history, prescriptions, and health examinations. The analysis used the World Health Organization’s ICD-10 definitions to categorize hearing loss types and examine their prevalence and incidence across various demographics over 11 years.
Results:
There was an overall annual increase of 4.62% in diagnosed cases of hearing loss, with the most significant rise among the elderly. The rate of increase accelerated from 3.32% between 2010 and 2014 to 6.49% between 2014 and 2020, corresponding with the improved hearing aid access facilitated by policy changes. Women showed a slightly higher increase than men. The data also indicated a consistent rise in abnormal hearing test results during health examinations, especially in older adults.
Conclusion
The study highlights an increasing trend in hearing loss diagnoses, driven by an aging population and enhanced detection facilitated by policy changes. These findings emphasize the need for continuous monitoring and targeted health policies to manage hearing loss effectively, offering valuable insights for global health management and policy development.
2.Part 2. Current Status of Hearing Disability and Hearing Rehabilitation Devices in Korea Using National Data: NHIS-Database, 2010 to 2020
Junhun LEE ; Chul Young YOON ; Jiwon KIM ; In-Ki JIN ; Michelle J. SUH ; Wan-Ho CHO ; Hyo-Jeong LEE ; Seong Jun CHOI ; Dongchul CHA ; Kyung Ho PARK ; Soo Hee OH ; Young Joon SEO ; Tae Hoon KONG
Korean Journal of Otolaryngology - Head and Neck Surgery 2025;68(3):94-104
Background and Objectives:
This study aims to analyze trends in hearing disability and the use of hearing rehabilitation devices (hearing aids and cochlear implants) in South Korea over the past 11 years (2010-2020) using data from the National Health Insurance Service (NHIS).Subjects and Method Data were extracted from the NHIS database, covering approximately 97% of the South Korean population. Patients diagnosed with hearing loss were classified using ICD-10 codes. The data were analyzed to determine trends in hearing disability, hearing aid prescriptions, and cochlear implant usage by age, gender, and types and causes of hearing loss.
Results:
The number of hearing disability patients increased from 170900 in 2010 to 362738 in 2020, with an annual growth rate of 7.95%. The highest increase was observed in the ≥60 age group, with an annual growth rate of 11.04%. Hearing aid prescriptions rose from 4966 in 2010 to 11974 in 2020, showing a 10.45% annual increase. Females showed a higher growth rate in both hearing disability and hearing aid prescriptions compared to males. Cochlear implant prescriptions also increased, particularly among older adults.
Conclusion
The study highlights a significant rise in hearing disability and the use of hearing aids and cochlear implants in South Korea, especially among the elderly. The findings underscore the importance of early diagnosis and intervention for hearing loss and the need for policy improvements to enhance accessibility and affordability of hearing rehabilitation services. Additional strategies are needed to ensure appropriate hearing rehabilitation for those not yet receiving adequate care.
3.Prevalence of asymptomatic malaria in high- and low-transmission areas of Tanzania: The role of asymptomatic carriers in malaria persistence and the need for targeted surveillance and control efforts
Ernest MAZIGO ; Hojong JUN ; Wang-Jong LEE ; Johnsy Mary LOUIS ; Fadhila FITRIANA ; Jadidan Hada SYAHADA ; Fauzi MUH ; Feng LU ; Md Atique AHMED ; Seok Ho CHA ; Wanjoo CHUN ; Won Sun PARK ; Se Jin LEE ; Sunghun NA ; Joon-Hee HAN ; Nyalali KIJA ; Smart GEODFREY ; Eun-Teak HAN ; Jim TODD ; Alphaxard MANJURANO ; Winifrida KIDIMA ; Jin-Hee HAN
Parasites, Hosts and Diseases 2025;63(1):57-65
As many countries implement different programs aimed at eliminating malaria, attention should be given to asymptomatic carriers that may interrupt the progress. This was a community-based cross-sectional study conducted in Tanzania from December 2022 to July 2023 within 4 villages from each of the 3 regions, Geita and Kigoma, which are high malaria transmission, and Arusha, which is low transmission. Malaria was diagnosed in asymptomatic individuals aged 1 year and older using the malaria rapid diagnostic test and light microscope. A total of 2,365 of 3,489 (67.9%) participants were enrolled from high-transmission villages. The overall prevalence was 25.5% and 15.8% by malaria rapid diagnostic test and light microscope, respectively. Using the respective tools, the prevalence was significantly higher at 35.6% (confidence interval (CI)=23.6–49.9) and 23.1% (CI=16.2–35.1) in the high-transmission regions (Geita and Kigoma) compared with 2.9% (CI=1.1–3.5) and 1.1% (CI=0.7–1.8) in the low-transmission region (Arusha). Children younger than 15 years and males accounted for the greatest proportion of infections. In the study area, the prevalence of asymptomatic cases was higher than that of reported symptomatic cases in health facilities. We hypothesize that these parasite reservoirs may contribute to the persistence of malaria in the country. Therefore, to achieve comprehensive malaria control in the country, the surveillance and screening of asymptomatic malaria cases are vital.
4.Anti-tumor effects of Toxoplasma gondii and antigen-pulsed dendritic cells in mice bearing breast cancer
Bong Kyun KIM ; Hei Gwon CHOI ; Jae-Hyung LEE ; In Wook CHOI ; Jae-Min YUK ; Guang-Ho CHA ; Young-Ha LEE
Parasites, Hosts and Diseases 2025;63(1):37-49
Cancer immunotherapy is widely used to treat various cancers to augment the weakened host immune response against tumors. Dendritic cells (DCs) are specialized antigen-presenting cells that play dual roles in inducing innate and adaptive immunity. Toxoplasma gondii is a protozoan parasite that exhibits anti-tumor activity against certain types of cancers. However, little is known about the anti-tumor effects of T. gondii or tumor/parasite antigen-pulsed DCs (DC vaccines, DCV) in breast cancer. In this study, C57BL/6 mice were administered E0771 mouse breast cancer cells (Cancer-injected) subcutaneously, T. gondii Me49 cysts orally (TG-injected), or DCs pulsed with breast cancer cell lysate antigen and T. gondii lysate antigens (DCV-injected) intraperitoneally. Tumor size and immunological characteristics were subsequently evaluated. We also evaluated matrix metalloproteinase (MMP)-2 and MMP-9 levels in E0771 mouse breast cancer cells co-cultured with T. gondii or DCs by RT-PCR. The tumor volumes of mice injected with breast cancer cells and antigen-pulsed DCs (Cancer/DCV-injected mice) were similar to those of Cancer-injected mice; however, they were significantly reduced in T. gondii-infected tumor-bearing (TG/Cancer-injected) mice. Moreover, tumor volumes were significantly reduced by adding antigen-pulsed DCs (TG/Cancer/DCV-injected mice) compared to TG/Cancer-injected mice. The levels of IFN-γ, serum IgG2a levels, and CD8+ T cell populations were significantly higher in DCV- and TG-injected mice than in control mice, while no significant differences between Cancer- and Cancer/DCV-injected mice were observed. The levels of IFN-γ, the IgG2a levels, and the percentage of CD8+ T cells were significantly increased in TG/Cancer- and TG/Cancer/DCV-injected mice than in Cancer-injected mice. IFN-γ levels and serum IgG2a levels were further increased in TG/Cancer/DCV-injected mice than in TG/Cancer-injected mice. The MMP-2 and MMP-9 mRNA expressions were significantly decreased in mouse breast cancer cells co-cultured with live T. gondii, T. gondii lysate antigen, or antigen-pulsed DCs (DCV) but not in inactivated DCs. These results indicate that T. gondii induces anti-tumor effects in breast cancer-bearing mice through the induction of strong Th1 immune responses, but not in antigen-pulsed DCs alone. The addition of antigen-pulsed DCs further augments the anti-tumor effects of T. gondii.
5.Long-Term Incidence of Gastrointestinal Bleeding Following Ischemic Stroke
Jun Yup KIM ; Beom Joon KIM ; Jihoon KANG ; Do Yeon KIM ; Moon-Ku HAN ; Seong-Eun KIM ; Heeyoung LEE ; Jong-Moo PARK ; Kyusik KANG ; Soo Joo LEE ; Jae Guk KIM ; Jae-Kwan CHA ; Dae-Hyun KIM ; Tai Hwan PARK ; Kyungbok LEE ; Hong-Kyun PARK ; Yong-Jin CHO ; Keun-Sik HONG ; Kang-Ho CHOI ; Joon-Tae KIM ; Dong-Eog KIM ; Jay Chol CHOI ; Mi-Sun OH ; Kyung-Ho YU ; Byung-Chul LEE ; Kwang-Yeol PARK ; Ji Sung LEE ; Sujung JANG ; Jae Eun CHAE ; Juneyoung LEE ; Min-Surk KYE ; Philip B. GORELICK ; Hee-Joon BAE ;
Journal of Stroke 2025;27(1):102-112
Background:
and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes.
Methods:
We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data.
Results:
Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2 , and a 3-month modified Rankin Scale score of ≥4.
Conclusion
Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.
6.Complete or incomplete revascularization in patients with left main culprit lesion acute myocardial infarction with multivessel disease: a retrospective observational study
Sun Oh KIM ; Hong-Ju KIM ; Jong-Il PARK ; Kang-Un CHOI ; Jong-Ho NAM ; Chan-Hee LEE ; Jang-Won SON ; Jong-Seon PARK ; Sung-Ho HER ; Ki-Yuk CHANG ; Tae-Hoon AHN ; Myung-Ho JEONG ; Seung-Woon RHA ; Hyo-Soo KIM ; Hyeon-Cheol GWON ; In-Whan SEONG ; Kyung-Kuk HWANG ; Seung-Ho HUR ; Kwang-Soo CHA ; Seok-Kyu OH ; Jei-Keon CHAE ; Ung KIM
Journal of Yeungnam Medical Science 2025;42(1):18-
Background:
Complete revascularization has demonstrated better outcomes in patients with acute myocardial infarction (AMI) and multivessel disease. However, in the case of left main (LM) culprit lesion AMI with multivessel disease, there is limited evidence to suggest that complete revascularization is better.
Methods:
We reviewed 16,831 patients in the Korea Acute Myocardial Infarction Registry who were treated from July 2016 to June 2020, and 399 patients were enrolled with LM culprit lesion AMI treated with percutaneous coronary intervention. We categorized the patients as those treated with complete revascularization (n=295) or incomplete revascularization (n=104). The study endpoint was major adverse cardiac and cerebrovascular events (MACCE), a composite of all-cause death, myocardial infarction, ischemia-driven revascularization, stent thrombosis, and stroke. We performed propensity score matching (PSM) and analyzed the incidence of MACCE at 1 year.
Results:
After PSM, the two groups were well balanced. There was no significant difference between the two groups in MACCE at 1 year (12.1% vs. 15.2%; hazard ratio, 1.28; 95% confidence interval, 0.60–2.74; p=0.524) after PSM. The components of MACCE and major bleeding were also not significantly different.
Conclusion
There was no significant difference in clinical outcomes between the groups treated with complete or incomplete revascularization for LM culprit lesion AMI with multivessel disease.
7.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.
8.Tuberculous and Malignant Pleural Effusions With Adenosine Deaminase Levels of 40–70 IU/L: Trends in New Cases Over Time and Differentiation Between Groups
Jaehee LEE ; Jongmin PARK ; Jae Kwang LIM ; Ji Eun PARK ; Yong Hoon LEE ; Sun Ha CHOI ; Hyewon SEO ; Seung Soo YOO ; Shin Yup LEE ; Seung-Ick CHA ; Jae Yong PARK ; Chang Ho KIM
Journal of Korean Medical Science 2025;40(13):e35-
Background:
The diagnosis of tuberculous pleural effusion (TPE) often relies on pleural fluid adenosine deaminase (ADA) levels. The diagnostic utility of ADA, however, is influenced by the prevalence of tuberculosis (TB) in local populations. Malignant pleural effusion (MPE) cases can exhibit moderately elevated ADA levels comparable to those seen in TPE. As population aging potentially impacts ADA levels, global TB incidence is decreasing whereas the burden of malignancy is on the rise. Consequently, epidemiological shifts and temporal changes in ADA distribution complicate the differential diagnosis between TPE and MPE when ADA levels are within the 40–70 IU/L range. Nonetheless, data specific to this subset are scarce.
Methods:
This retrospective study included consecutive patients aged > 18 years with confirmed TPE and MPE, spanning from 2012 to 2023. ADA levels in pleural fluid were categorized into three groups: < 40 IU/L, 40–70 IU/L, and > 70 IU/L. The study examined annual trends in the frequency of new cases and ADA level distributions over time and identified discriminating factors between TPE and MPE in cases with ADA levels of 40–70 IU/L.
Results:
In total, 297 TPE and 369 MPE cases were included in this study. Over the study period, the frequency of TPE progressively declined, while that of MPE increased. In the most recent four-year period, new TPE and MPE cases with ADA levels of 40–70 IU/L occurred at comparable numbers. Multivariable analysis identified pleural fluid carcinoembryonic antigen (CEA) levels and the number of focal pleural nodules as independent predictors for MPE. Specifically, the presence of either CEA levels > 15.7 ng/mL or more than eight pleural nodules yielded the highest diagnostic accuracy with a sensitivity of 88%, specificity of 100%, and an area under the curve of 0.95.
Conclusion
The differential diagnosis between TPE and MPE with pleural ADA levels of 40–70 IU/L has become increasingly critical due to evolving epidemiological patterns and ADA distribution changes over time. Pleural fluid CEA levels and the characteristics of pleural nodules may offer valuable guidance in distinguishing between TPE and MPE within this diagnostic gray zone.
9.Global Burden of Vaccine-Associated Cerebrovascular Venous Sinus Thrombosis, 1968–2024: A Critical Analysis From the WHO Global Pharmacovigilance Database
Jaehyeong CHO ; Hyesu JO ; Hyunjee KIM ; Jaeyu PARK ; Damiano PIZZOL ; Min Seo KIM ; Ho Geol WOO ; Dong Keon YON
Journal of Korean Medical Science 2025;40(11):e101-
Despite widespread coronavirus disease 2019 (COVID-19) vaccine use, research on the association between vaccines and cerebrovascular venous sinus thrombosis (CVST) in diverse populations is limited. This study aimed to address this gap. Data from the World Health Organization pharmacovigilance database (1968–2024; total reports = 8,909,484) were used.Reporting odds ratios (RORs) and information components (ICs) were calculated to assess the association between each drug and CVST. In total, 851 cases were identified as vaccineassociated CVST, of which 527 (61.93%) occurred in female patients. Only Ad5-vectored COVID-19 vaccines had the highest ROR and IC value with CVST (ROR, 4.78; 95% confidence interval, 4.34–5.28; IC, 2.15). The risk of CVST increased with age, with the 45–64-years age group having an IC of 1.35, while the 65 years and older group had a higher IC of 2.08.The findings highlight the need for clinicians to recognize the potential risks of CVST and prioritize rigorous monitoring and research to ensure patient safety.
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.

Result Analysis
Print
Save
E-mail