1.Relationship Between Coronavirus Disease 2019 Vaccination Rates and Rare But Potentially Fatal Adverse Events: A Regression Discontinuity Analysis of Western Countries
Seung Hoon CHAE ; Hyung Jun PARK ; Munkhzul RADNAABAATAR ; Hojun PARK ; Jaehun JUNG
Journal of Korean Medical Science 2023;38(11):e94-
Background:
Owing to limited experience with the new vaccine platforms, discussion of vaccine safety is inevitable. However, media coverage of adverse events of special interest could influence the vaccination rate; thus, evaluating the outcomes of adverse events of special interest influencing vaccine administration is crucial.
Methods:
We conducted regression discontinuity in time analysis to calculate the local average treatment effect (LATE) using datasets from Our World in Data and Johns Hopkins University Center for Systems Science and Engineering. For the United States, the United Kingdom, and Europe, the cutoff points were April 23rd and June 23rd, April 7th, and the 14th week of 2021, respectively.
Results:
The LATE of the Advisory Committee on Immunization Practices (ACIP) meeting held on April 23rd was −0.249 for all vaccines, −0.133 (−0.189 to −0.076) for Pfizer, −0.064 (−0.115 to −0.012) for Moderna, and −0.038 (−0.047 to −0.030) for Johnson & Johnson. Discontinuities were observed for all three types of vaccines in the United States. The June 23rd meeting of the ACIP (mRNA vaccines and myocarditis) did not convene any discontinuities. Furthermore, there was no significant drop in the weekly average vaccination rates in Europe following the European Medicines Agency (EMA) statement on April 7th. Conversely, there was a significant drop in the first-dose vaccination rates in the United Kingdom related to the EMA report. The first-dose vaccination rate for all vaccines changed by −0.104 (−0.176 to −0.032).
Conclusion
Although monitoring and reporting of adverse events of special interest are important, a careful approach towards public announcements is warranted.
2.Regional Differences in Years of Life Lost in Korea from 1997 to 2015
Dun Sol GO ; Young Eun KIM ; Munkhzul RADNAABAATAR ; Yunsun JUNG ; Jaehun JUNG ; Seok Jun YOON
Journal of Korean Medical Science 2019;34(Suppl 1):e91-
BACKGROUND:
Reducing the gaps in health inequality at a regional level and improving health equity have been emphasized in Korea, it is essential to accurately measure the burden of disease by region. This study aimed to estimate years of life lost (YLLs) in 17 Si and Do of Korea from 1997 to 2015 and determine the trends of regional differences in health status and disease structure.
METHODS:
YLL was calculated by subtracting the age at death from the life expectancy. Data on the region, gender, and age-stratified cause-specific death were obtained from the Korean Statistical Information Service of Statistics Korea.
RESULTS:
Age-standardized YLLs per 100,000 population decreased by year in all regions from 1997 to 2015 by 27.4% (27.5% for men; 27.2% for women). Despite the decline in YLLs, the regions with the highest and lowest YLLs did not change between 1997 and 2015. The diseases showing regional differences were caused by injury, often classified as avoidable mortality. We also confirmed that YLLs were higher in the regions with a higher deprivation index.
CONCLUSION
The present study identified that YLLs differed by regions in Korea with specific causes. The findings of this study can be used by decision-makers to prioritize the reduction of regional gaps in premature deaths.
3.Predicted and Observed Incidence of Thromboembolic Events among Koreans Vaccinated with ChAdOx1 nCoV-19 Vaccine
Kyungmin HUH ; Yewon NA ; Young-Eun KIM ; Munkhzul RADNAABAATAR ; Kyong Ran PECK ; Jaehun JUNG
Journal of Korean Medical Science 2021;36(27):e197-
We used the nationwide claims database to calculate the incidence of thrombotic events and predict their overall 2-week incidence. From 2006 to 2020, the incidence of deep vein thrombosis (DVT), pulmonary embolism (PE), and disseminated intravascular coagulation (DIC) tended to increase. Unlike intracranial venous thrombosis (ICVT) and intracranial thrombophlebitis (ICTP), which showed no age difference, other venous embolism, and thrombosis (OVET), DIC, DVT, and PE were significantly more common in over 65 years.The overall 2-week incidence of ICVT was 0.21/1,000,000 (95% confidence interval [CI], 0.11–0.32). ICTP, OVET, DIC, DVT and PE were expected to occur in 0.08 (95% CI, 0.02– 0.14), 7.66 (95% CI, 6.08–9.23), 5.95 (95% CI, 4.88–7.03), 13.28 (95% CI, 11.92–14.64), 14.09 (95% CI, 12.80–15.37) per 1,000,000, respectively. To date, of 8,548,231 patients vaccinated with ChAdOx1 nCoV-19 in Korea, two had confirmed thrombosis with thrombocytopenia syndrome within 2 weeks. The observed incidence of ICVT after vaccination was 0.23/1,000,000.
4.Predicted and Observed Incidence of Thromboembolic Events among Koreans Vaccinated with ChAdOx1 nCoV-19 Vaccine
Kyungmin HUH ; Yewon NA ; Young-Eun KIM ; Munkhzul RADNAABAATAR ; Kyong Ran PECK ; Jaehun JUNG
Journal of Korean Medical Science 2021;36(27):e197-
We used the nationwide claims database to calculate the incidence of thrombotic events and predict their overall 2-week incidence. From 2006 to 2020, the incidence of deep vein thrombosis (DVT), pulmonary embolism (PE), and disseminated intravascular coagulation (DIC) tended to increase. Unlike intracranial venous thrombosis (ICVT) and intracranial thrombophlebitis (ICTP), which showed no age difference, other venous embolism, and thrombosis (OVET), DIC, DVT, and PE were significantly more common in over 65 years.The overall 2-week incidence of ICVT was 0.21/1,000,000 (95% confidence interval [CI], 0.11–0.32). ICTP, OVET, DIC, DVT and PE were expected to occur in 0.08 (95% CI, 0.02– 0.14), 7.66 (95% CI, 6.08–9.23), 5.95 (95% CI, 4.88–7.03), 13.28 (95% CI, 11.92–14.64), 14.09 (95% CI, 12.80–15.37) per 1,000,000, respectively. To date, of 8,548,231 patients vaccinated with ChAdOx1 nCoV-19 in Korea, two had confirmed thrombosis with thrombocytopenia syndrome within 2 weeks. The observed incidence of ICVT after vaccination was 0.23/1,000,000.
5.Optimal Social Distancing Policy for COVID-19 Control in Korea:A Model-Based Analysis
Youngji JO ; Sourya SHRESTHA ; Munkhzul RADNAABAATAR ; Hojun PARK ; Jaehun JUNG
Journal of Korean Medical Science 2022;37(23):e189-
Background:
Since March 2020, when coronavirus disease 2019 (COVID-19) was declared a pandemic, many countries have applied unprecedented restrictive measures to contain the spread of the virus. This study aimed to explore the optimal social distancing policy for COVID-19 control in South Korea to safely reopen the society.
Methods:
We developed an age-specific, deterministic compartment epidemic model to examine the COVID-19 control decision-making process, including the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between 1 July 2021 and 30 December 2022.The model consists of the natural history of COVID-19, testing performance, vaccinations, and social distancing enforcement measures to detect and control SARS-CoV-2. We modelled potential intervention scenarios with three distinct components: 1) social distancing duration and level;2) testing intensity; and 3) vaccination uptake rate. The primary and secondary outcomes were COVID-19 incidence and prevalence of severe patients requiring intensive care unit (ICU) care.
Results:
Four (or more) months of social distancing (that can reduce 40–60% transmission) may mitigate epidemic resurgence and ICU demand in the future and keep the cases below the capacity limit if the testing intensity and vaccination rate remain constant or increase by 20% (with respect to the current level). In contrast, two months of strict social distancing enforcement may also successfully mitigate future epidemic surge and ICU demand as long as testing intensity and vaccination rates are increased by 20%.
Conclusion
In South Korea, given the relatively high vaccination coverage and low incidence, four or more months of social distancing enforcement can effectively mitigate epidemic resurgence after lifting the social distancing measures. In addition, increasing the testing intensity and vaccination rate may help reduce necessary social distancing levels and duration to prevent a future epidemic resurgence and mitigate social and economic damage.
6.Insights Into JKMS Submissions and Medical Journal Publications in Korea
Jaehun JUNG ; Yumi JANG ; Munkhzul RADNAABAATAR ; Dae Sun JO ; Jong-Min KIM ; Jin-Hong YOO
Journal of Korean Medical Science 2025;40(1):e76-
We analyzed the publication and submission statuses of Korean medical journals from 2010 to 2024, amidst challenges impacting researchers. Data from 58 domestic journals identified through the 2023 JCR database were used to assess publication status, while data from the Journal of Korean Medical Science (JKMS) were utilized to examine submission status.The proportion of published original articles by domestic authors decreased by 3% in 2024 compared to 2023. Submissions to JKMS also decreased overall, except for slight increases in May and October 2024. In contrast, international submissions to JKMS showed consistent growth, surpassing the 15-year average, reflecting growing global interest. Addressing issues, including medical school admission policies and the lingering effects of coronavirus disease 2019, is vital to ensure a sustainable and thriving medical research environment in Korea.
7.Insights Into JKMS Submissions and Medical Journal Publications in Korea
Jaehun JUNG ; Yumi JANG ; Munkhzul RADNAABAATAR ; Dae Sun JO ; Jong-Min KIM ; Jin-Hong YOO
Journal of Korean Medical Science 2025;40(1):e76-
We analyzed the publication and submission statuses of Korean medical journals from 2010 to 2024, amidst challenges impacting researchers. Data from 58 domestic journals identified through the 2023 JCR database were used to assess publication status, while data from the Journal of Korean Medical Science (JKMS) were utilized to examine submission status.The proportion of published original articles by domestic authors decreased by 3% in 2024 compared to 2023. Submissions to JKMS also decreased overall, except for slight increases in May and October 2024. In contrast, international submissions to JKMS showed consistent growth, surpassing the 15-year average, reflecting growing global interest. Addressing issues, including medical school admission policies and the lingering effects of coronavirus disease 2019, is vital to ensure a sustainable and thriving medical research environment in Korea.
8.Insights Into JKMS Submissions and Medical Journal Publications in Korea
Jaehun JUNG ; Yumi JANG ; Munkhzul RADNAABAATAR ; Dae Sun JO ; Jong-Min KIM ; Jin-Hong YOO
Journal of Korean Medical Science 2025;40(1):e76-
We analyzed the publication and submission statuses of Korean medical journals from 2010 to 2024, amidst challenges impacting researchers. Data from 58 domestic journals identified through the 2023 JCR database were used to assess publication status, while data from the Journal of Korean Medical Science (JKMS) were utilized to examine submission status.The proportion of published original articles by domestic authors decreased by 3% in 2024 compared to 2023. Submissions to JKMS also decreased overall, except for slight increases in May and October 2024. In contrast, international submissions to JKMS showed consistent growth, surpassing the 15-year average, reflecting growing global interest. Addressing issues, including medical school admission policies and the lingering effects of coronavirus disease 2019, is vital to ensure a sustainable and thriving medical research environment in Korea.
9.Insights Into JKMS Submissions and Medical Journal Publications in Korea
Jaehun JUNG ; Yumi JANG ; Munkhzul RADNAABAATAR ; Dae Sun JO ; Jong-Min KIM ; Jin-Hong YOO
Journal of Korean Medical Science 2025;40(1):e76-
We analyzed the publication and submission statuses of Korean medical journals from 2010 to 2024, amidst challenges impacting researchers. Data from 58 domestic journals identified through the 2023 JCR database were used to assess publication status, while data from the Journal of Korean Medical Science (JKMS) were utilized to examine submission status.The proportion of published original articles by domestic authors decreased by 3% in 2024 compared to 2023. Submissions to JKMS also decreased overall, except for slight increases in May and October 2024. In contrast, international submissions to JKMS showed consistent growth, surpassing the 15-year average, reflecting growing global interest. Addressing issues, including medical school admission policies and the lingering effects of coronavirus disease 2019, is vital to ensure a sustainable and thriving medical research environment in Korea.
10.Estimating Baseline Incidence of Conditions Potentially Associated with Vaccine Adverse Events: a Call for Surveillance System Using the Korean National Health Insurance Claims Data
Kyungmin HUH ; Young-Eun KIM ; Munkhzul RADNAABAATAR ; Dae Ho LEE ; Dong Wook KIM ; Soon-Ae SHIN ; Jaehun JUNG
Journal of Korean Medical Science 2021;36(9):e67-
Background:
Vaccines against coronavirus disease 2019 (COVID-19) are raising concerns about vaccine safety, particularly in the context of large-scale immunization. To address public concerns, we measured the baseline incidence rates of major conditions potentially related to vaccine-related adverse events (VAEs). We aimed to provide a basis for evaluating VAEs and verifying causality.
Methods:
Conditions of interest were selected from the US Vaccine Adverse Event Reporting System Table of Reportable Events and a recent report from a European consortium on vaccine surveillance. We used the National Health Insurance Service database in Korea to identify the monthly numbers of cases with these conditions. Data from January 2006 to June 2020 were included. Prediction models were constructed from the observed incidences using an autoregressive integrated moving average. We predicted the incidences of the conditions and their respective 95% confidence intervals (CIs) for January through December 2021. In addition, subgroup analysis for the expected vaccination population was conducted.
Results:
Mean values (95% CIs) of the predicted monthly incidence of vasovagal syncope, anaphylaxis, brachial neuritis, acute disseminated encephalomyelitis, Bell's palsy, Guillain-Barré syndrome, encephalopathy, optic neuritis, transverse myelitis, immune thrombocytopenic purpura, and systemic lupus erythematosus in 2021 were 23.89 (19.81– 27.98), 4.72 (3.83–5.61), 57.62 (51.37–63.88), 0.03 (0.01–0.04), 8.58 (7.90–9.26), 0.26 (0.18– 0.34), 2.13 (1.42–2.83), 1.65 (1.17–2.13), 0.19 (0.14–0.25), 0.75 (0.61–0.90), and 3.40 (2.79– 4.01) cases per 100,000 respectively. The majority of the conditions showed an increasing trend with seasonal variations in their incidences.
Conclusion
We measured the incidence of a total of 11 conditions that could potentially be associated with VAEs to predict the monthly incidence in 2021. In Korea, conditions that could potentially be related to VAEs occur on a regular basis, and an increasing trend is observed with seasonality.