South Korea's National Research Articles

Analyzing the dynamics of complicated and uncomplicated appendicitis during the COVID-19 pandemic in Seoul: a multifaceted time series approach.

This study investigated the impact of the COVID-19 pandemic and associated control strategies on the incidence of appendicitis in Seoul, using data from 2018 to 2020 from South Korea's National Health Insurance. We analyzed records of total, complicated, and uncomplicated appendicitis cases, as well as the ratio of complicated to uncomplicated appendicitis, using natural spline and piecewise regression models to identify trends and breakpoints. Bayesian structural time-series (BSTS) models were used to evaluate the causal impact of social distancing on appendicitis incidences. The spline regression analysis indicated decreasing trends in both total and uncomplicated appendicitis cases. Conversely, the incidence of complicated appendicitis and the ratio of complicated to uncomplicated cases increased. Breakpoints for a decline in uncomplicated appendicitis and a rise in the ratio occurred at 31 weeks in 2020 (95% confidence interval [CI], 23.2 to 38.8) and at 33.9 weeks (95% CI, 28.3 to 39.6), respectively. The BSTS model demonstrated a 7.8% reduction in total appendicitis cases (95% credible interval [CrI], -12.0% to -3.3%). It also showed a 17% decrease in uncomplicated cases (95% CrI, -22% to -12%) and increases of 13% (95% CrI, 4.9% to 22.0%) in complicated cases and 39% (95% CrI, 27.0% to 53.0%) in the ratio of complicated to uncomplicated appendicitis. The COVID-19 pandemic resulted in a decrease in both total and uncomplicated appendicitis cases, while the number of complicated cases increased. Reduced medical visits likely accounted for these changes. Strategies are needed to manage changes in disease pathophysiology resulting from altered healthcare utilization during health crises.

Association of remnant cholesterol with risk of dementia: a nationwide population-based cohort study in South Korea

The association between remnant cholesterol (remnant-C) and cardiovascular disease risk is well established, but its association with dementia remains unclear. We aimed to examine this association using a large-scale population dataset. We did a nationwide, population-based cohort study in which we identified participants aged 40 years and older who underwent the national health examination in 2009 from South Korea's National Health Insurance Service. We excluded people who were younger than 40 years and those with a triglyceride concentration of 400 mg/dL or higher due to concerns regarding the accuracy of calculated low-density lipoprotein cholesterol concentration in individuals with extremely high triglyceride concentrations. People who were previously diagnosed with dementia before the index date, and those who had any missing variables were also excluded. To minimise the influence of possible reverse causation, we excluded individuals who had developed any type of dementia within 1 year of the baseline measurements. We calculated hazard ratios (HRs) for all-cause dementia, Alzheimer's disease, and vascular dementia in each quartile of remnant-C using the Cox proportional hazards model adjusted for age, sex, body-mass index, estimated glomerular filtration rate, income level, smoking status, alcohol consumption, regular exercise, diabetes, hypertension, statin and fibrate use, and total cholesterol concentrations. We also did subgroup analyses to investigate the association between remnant-C and the risk of dementia stratified by age, sex, obesity, glycaemic status (normoglycaemia, impaired fasting glucose, new-onset type 2 diabetes, type 2 diabetes with a duration of less than 5 years, and type 2 diabetes with a duration of 5 years or more), hypertension, chronic kidney disease, and dyslipidaemia, using likelihood ratio tests. 4 234 415 individuals who underwent the national health examination in 2009 were deemed eligible for inclusion. We excluded 1 612 819 individuals on the basis of age, triglyceride concentration, missing variables, or having dementia at baseline. We identified 2 621 596 participants aged 40 years and older (1 305 556 men and 1 316 040 women) who underwent the national health examination and followed them up until the date of any incident of dementia or the end of the study period of Dec 31, 2020. During a median follow-up of 10·3 years (IQR 10·1-10·6), 146 991 (5·6%) participants developed all-cause dementia, 117 739 (4·5%) developed Alzheimer's disease, and 14 536 (0·6%) developed vascular dementia. The risk of dementia increased progressively with higher remnant-C concentrations. Compared with the lowest quartile of remnant-C (quartile 1), HRs in the highest quartile (quartile 4) were 1·11 (95% CI 1·09-1·13) for all-cause dementia, 1·11 (1·08-1·13) for Alzheimer's disease, and 1·15 (1·09-1·21) for vascular dementia. Subgroup analyses revealed that the risk of dementia associated with high remnant-C concentrations was higher in middle-aged people aged 40-59 years than in older people. The risk of dementia associated with high concentrations of remnant-C was notably more pronounced in individuals with diabetes compared with those without diabetes, and the risk increased steeply with a longer duration of diabetes. Results showed that higher remnant-C concentrations were independently associated with increased risks of all-cause dementia, Alzheimer's disease, and vascular dementia. More research is needed to determine the mechanisms underlying this finding. Monitoring and managing higher concentrations of remnant-C might have important implications for reducing the risk of dementia. None.

Attention-deficit/hyperactivity disorder and subsequent diagnoses of major psychiatric disorders: a nationwide population-based study.

We evaluated the risk of being diagnosed with various psychiatric disorders after an attention-deficit/hyperactivity disorder (ADHD) diagnosis using data from South Korea's National Health Insurance Service from 2002 to 2019, which covers approximately 97% of the country's population. ADHD and control groups were selected after propensity score matching was performed for individuals diagnosed with ADHD and their age- and sex-matched counterparts from the general population. Comorbid psychiatric disorders included depressive disorder, bipolar disorder, tic disorder, and schizophrenia. The incidence of newly diagnosed psychiatric disorders was compared between the groups. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated and adjusted for ADHD medication prescription. After matching, 353,898 individuals were assigned to each of the two groups. Compared to the control group, the ADHD group showed a significantly higher risk of being subsequently diagnosed with depressive disorder, bipolar disorder, schizophrenia, and tic disorder. The onset age of depressive disorder, bipolar disorder, and schizophrenia in the ADHD group was 16-17 years, approximately 5 years earlier than that in the control group. The risk for depression was the highest in individuals with high income levels, and that for schizophrenia was the highest among rural patients. The median length of the follow-up time until the diagnosis of each comorbid psychiatric disorder was 7.53, 8.43, 8.53, and 8.34 years for depressive disorder, bipolar disorder, schizophrenia, and tic disorder, respectively. Individuals with ADHD had an overall higher risk of being diagnosed with subsequent psychiatric disorders than did the controls. Hence, they should be carefully screened for other psychiatric symptoms from an early age and followed up for an extended duration, along with appropriate interventions for ADHD symptoms, including psychosocial treatments and educational approaches.

STAD-GCN: Spatial–Temporal Attention-based Dynamic Graph Convolutional Network for retail market price prediction

As technology advances, competition among market players intensifies, highlighting the importance of comprehending both one’s own and competitors’ pricing strategies. Traditional approaches often rely on static factors for price forecasting, disregarding the dynamic nature of market competition. In contrast to methods utilizing a static graph structure and uniform weights for predictions, we introduce STAD-GCN (Spatial–Temporal Attention-based Dynamic Graph Convolutional Network). This innovative model dynamically incorporates competitive factors into price prediction by employing attention mechanisms and graph convolution operations. Such an approach allows for the adaptation of graph structures and node relationships in response to temporal and spatial changes, offering a more nuanced understanding of market dynamics. To test STAD-GCN, we utilized international and domestic oil price data alongside specific gas station details from the South Korea National Oil Corporation, focusing on Seoul and Busan. The model presents remarkable performance, achieving mean absolute errors of 12.648 in Seoul and 11.242 in Busan, surpassing state-of-the-art models. Based on the findings of our research, we present some academic and practical implications, as well as several future research directions.

Investigating Factors Influencing the National Cancer Screening Program among Older Individuals in Republic of Korea-Data from the Korea National Health and Nutrition Examination Survey VIII.

This study aims to determine the influencing factors of the participation of older individuals aged 65 years and above in South Korea's National Cancer Screening Program (NCSP) using data from the eighth wave (2019-2021) of the Korea National Health and Nutrition Examination Survey (KNHANES VIII), and discuss potential problems and coping strategies. Variables were selected based on Andersen's healthcare utilization model. "Participation in the NSCP" was considered the dependent variable, with independent variables including sociodemographic characteristics (sex, marital status, residence, education level, income level, economic activity, medical coverage type, and private insurance), health conditions (subjective health status, hypertension, and diabetes), and health behaviors (physical activity, monthly alcohol consumption, and current smoking status). The analysis revealed that higher participation rates correlated with being married, having an education level beyond elementary school, being employed, subscribing to private insurance, perceiving oneself as having average or poor health, engaging in physical activity, and not smoking. Sex, residence, income, medical coverage type, hypertension, diabetes, and monthly alcohol consumption were found to be insignificantly correlated. These findings underscore the importance of tailored promotion and health education for older individuals to boost NCSP participation rates, which could ultimately elevate public health standards.

How to determine the focus of emergent medical care in healthcare policy: Proposal of treatable death

IntroductionThe global provision of essential healthcare stands as a critical concern. Consequently, healthcare policies play a pivotal role in determining the allocation of resources. However, the optimal indicators for prioritizing such policies remain uncertain. This study proposes that employing the concept of treatable mortality in a stepwise manner could serve as a viable approach to setting healthcare policy priorities. Furthermore, it aims to demonstrate this concept through the application of real-world data. MethodsA model was developed to assess treatable mortality at a national level focusing on severe emergency conditions. We established stepwise targets, encompassing short-term, mid-term, and long-term goals to reduce mortality rates and enhance healthcare efficiency. The short-term target consists of directing attention to regions exhibiting in-hospital mortality rates surpassing the national average within a specific disease category and reducing them to the national average. The mid-term objective entails decreasing the in-hospital mortality rate of the specific disease group to match that of the region with the lowest rate nationwide. As for long-term target, it aligns the in-hospital mortality rate with that of OECD countries possessing average or lowest rates. The model was applied using data from South Korea's National Emergency Department Information System, specifically analyzing acute myocardial infarction (AMI), stroke, and sepsis. ResultsReaching the short-term target resulted in the treatable deaths for AMI numbered 191, for stroke 249, and for sepsis 546. Meeting the mid-term target led to treatable deaths for AMI at 749, for stroke at 958, and for sepsis at 1552. Finally, achieving the long-term target yielded the treatable deaths for AMI at 2606, for stroke at 1642, and for sepsis at 2619. Consequently, a reallocation of more healthcare resources to sepsis over AMI or stroke is recommended. ConclusionsThis study proposes the utilization of treatable mortality as a metric for establishing healthcare policies. The stepwise approach provides valuable insights for policymaking at various levels. Despite limitations, the model offers a foundation for resource allocation and international mortality rate comparisons, aiming for achievable rates worldwide.

COVID-19 and Neurodevelopmental Delays in Early Childhood: A Longitudinal Analysis of Developmental Outcomes in Korean Children.

This study employed a longitudinal analysis to evaluate the association between the coronavirus disease 2019 pandemic and neurodevelopment by analyzing over 1.8 million children from the Korean Developmental Screening Test for Infants and Children included in South Korea's National Health Screening Program. We compared the developmental outcomes in five age groups-9-17 months, 18-29 months, 30-41 months, 42-53 months, and 54-65 months-between the pre-pandemic (2018-2019) and pandemic (2020-2021) periods. Significant increases in potential developmental delays were observed during the pandemic in communication, cognitive, social interaction, self-care, and fine motor skills across most age groups. All five age groups experienced notable disruptions in communication and fine motor skills. Children from socioeconomically disadvantaged backgrounds faced higher risks across all domains. These findings highlight the need for targeted interventions and continuous monitoring to support the developmental needs of children affected by pandemic-related disruptions.

재난안전법에 있어서 국가핵심기반 제도 도입과정의 법적 고찰

Over the past two decades since the National Core Infrastructure legislation was introduced, substantial progress has been made in various related legislations, such as those governing Critical Infrastructure and National Infrastructure, leading to the development of a more refined legal framework. However, there are still uncertainties regarding the extent of legal completeness embodied in the current definition of National Core Infrastructure. Evaluating how well the objectives of these legislative revisions have been or can be achieved, especially in comparison to existing terms like National Infrastructure, is crucial. This necessity stems from the fact that the legislative process for the National Core Infrastructure was carried out with no discussions on its legal nature or functions at key committees like the Administrative Security Committee or the Legal Affairs and Judiciary Committee. This study aims to scrutinize the objectives underlying the establishment of the National Core Infrastructure Act and identify challenges, limitations, and potential improvements in the current operation of South Korea's National Core Infrastructure legal system.국가핵심기반, 재난안전법, 입법과정, 국가기반시설, 국가기반체계

The risk of pediatric cardiovascular diseases in offspring born to mothers with systemic lupus erythematosus: a nationwide study.

Systemic lupus erythematosus (SLE), a common autoimmune disease predominantly affecting women, has been linked to various complications during pregnancy. The transfer of anti-Ro/SSA antibodies from SLE-affected mothers to their offspring can lead to neonatal lupus and cardiac issues. This study investigated the association between maternal SLE and the risk of pediatric cardiovascular disorders. The study utilized South Korea's National Health Insurance Service (NHIS) database, covering 3,505,737 children born between 2007 and 2017 and tracked until 2020. Maternal SLE cases were identified using the World Health Organization's International Classification of Diseases Tenth revision (ICD-10) codes and linked with delivery records. Cardiologic disorders were categorized into congenital heart disease (CHD), arrhythmic disorders, and acquired heart disease. Propensity score matching with 1:4 ratios was applied to the set control group. Among 3,505,737 children, 0.7% (n = 23,330) were born to mothers with SLE. The incidence of preterm birth was significantly higher in the maternal SLE group (5.9% vs. 3.0%). Compared with the control group, children born to mothers with SLE exhibited a significantly elevated risk of overall CHDs (5.5%, adjusted odds ratio [aOR] 1.21; 95% confidence interval [CI] 1.14-1.29), including atrial septal defect (1.18; 1.09-1.28) and patent ductus arteriosus (1.15; 1.03-1.30). In addition, a notably higher risk was observed in arrhythmic disorders (complete atrioventricular block 7.20; 2.41-21.49) and acquired cardiac disorders, including cardiomyopathy (1.40; 1.17-1.68) and mucocutaneous lymph node syndrome (MCLS) (1.27; 1.15-1.43). Maternal SLE is associated with congenital and acquired cardiac disorders in offspring, including structural, arrhythmic, and MCLS. This study highlights the need for continuous cardiovascular monitoring from the prenatal stage to preadolescence in these children due to multifactorial influences involving maternal autoantibodies, genetic predisposition, and environmental factors.

Why do democratic societies tolerate undemocratic laws? Sorting public support for the National Security Act in South Korea

ABSTRACT This study investigates why anti-democratic laws persist in democratic societies, focusing on South Korea's National Security Act (NSA). Enacted in 1948, the NSA restricts freedom of expression and movement to deter pro-North Korea behaviour. Despite being at odds with the tenets of liberal democracy, the act remains in place. Existing public opinion data indicates modest to strong support for the law, but measurement concerns leave much to be desired. Using a choice-based conjoint, we test the impact of democratic norms and national security rationales on various policy propositions related to the NSA, including its abolition. Results show widespread support for the Act, driven by both democratic norms and security concerns. Progressives are more likely to support revisions limiting the scope of the Act on the basis that it safeguards democracy, but they agree with conservatives that it should not be abolished. This research contributes to understanding South Korea's post-democratic transition and the balance between national security and democracy more broadly.

Effect of changes in the hearing aid subsidy on the prevalence of hearing loss in South Korea.

South Korea's National Health Insurance has provided hearing aids to registered individuals with hearing disabilities since 1989. In 2015, hearing aid subsidies increased to approximately US$1,000. This study aimed to understand hearing loss categories in Korea by analyzing patients between 2010 and 2020 and the effect of the 2015 hearing aid policy change on the prevalence of hearing loss. The participants were patients registered on the National Health Insurance Service database from 2010 to 2020 with hearing loss. A total of 5,784,429 patients were included in this study. Hearing loss was classified into conductive, sensorineural, and other categories. Patients with hearing loss were classified according to the International Classification of Diseases diagnostic code. Disability diagnosis and hearing aid prescription were defined using the National Health Insurance Disability and Hearing Aid Code. The increase in hearing aid prescriptions and hearing disability registrations following the subsidy increase impacts hearing loss prevalence. Hearing aid prescription and hearing disability were found to have an effect on increasing hearing loss prevalence in univariate and multivariate analyses. The r-value of each analysis exceeded 0.95. Other hearing losses increased rapidly after the increased subsidy. A hearing-impaired individual must be diagnosed with a hearing disability and prescribed a hearing aid to receive the subsidy. The prevalence of hearing loss was affected by increased hearing disabilities following changes in the hearing aid subsidy and the number of people prescribed hearing aids. Therefore, caution should be exercised when studying hearing loss prevalence over mid-long-term periods.

The Rise of Ethnic Nationalism in South Korea: Moon's North Korea Policy and Inter-Korean Relations

What is the origin of South Korea's North Korea policy under the Moon Jae-in presidency? Are there any underlying assumptions and perspectives behind this policy? What kind of ideas and values have played out in South Korea's policy toward North Korea? By both exploring the idea of nationalism in current world politics and showing its influence on South Korea's policy discourse and orientation, in this article we argue that nationalism is still a powerful political ideology that affects state foreign policy and plays out as a strong variable in trying to make sense of South Korea's North Korea policy. To test this argument, we analyze recent inter-Korean interactions and illustrate how ethnic nationalism shaped the Moon administration's North Korea policy. As long as ethnic nationalism dominates policy debates and affects the policy orientation, the prospect of inter-Korean relations will not be promising.

Highly resolved mapping of NO2 vertical column densities from GeoTASO measurements over a megacity and industrial area during the KORUS-AQ campaign

Abstract. The Korea–United States Air Quality (KORUS-AQ) campaign is a joint study between the United States National Aeronautics and Space Administration (NASA) and the South Korea National Institute of Environmental Research (NIER) to monitor megacity and transboundary air pollution around the Korean Peninsula using airborne and ground-based measurements. Here, tropospheric nitrogen dioxide (NO2) slant column density (SCD) measurements were retrieved from Geostationary Trace and Aerosol Sensor Optimization (GeoTASO) L1B data during the KORUS-AQ campaign (2 May to 10 June 2016). The retrieved SCDs were converted to tropospheric vertical column densities using the air mass factor (AMF) obtained from a radiative transfer calculation with trace gas profiles and aerosol property inputs simulated with the Community Multiscale Air Quality (CMAQ) model and surface reflectance data obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS). For the first time, we examine highly resolved (250 m × 250 m resolution) tropospheric NO2 over the Seoul and Busan metropolitan regions and the industrial region of Anmyeon. We reveal that the maximum NO2 vertical column densities (VCDs) were 4.94×1016 and 1.46×1017 molec. cm−2 at 09:00 and 15:00 LT over Seoul, respectively, 6.86×1016 and 4.89×1016 molec. cm−2 in the morning and afternoon over Busan, respectively, and 1.64×1016 molec. cm−2 over Anmyeon. The VCDs retrieved from the GeoTASO airborne instrument were correlated with those obtained from the Ozone Monitoring Instrument (OMI) (r=0.48), NASA's Pandora Spectrometer System (r=0.91), and NO2 mixing ratios obtained from in situ measurements (r=0.07 in the morning, r=0.26 in the afternoon over the Seoul, and r>0.56 over Busan). Based on our results, GeoTASO is useful for identifying NO2 hotspots and their spatial distribution in highly populated cities and industrial areas.

Unintended health benefits of adopting preventive behaviors during a virus outbreak.

This study investigates whether changes in risk perception play a critical role in improving of preventive behaviors and health outcomes by examining the 2009 H1N1 influenza (or swine flu) pandemic in Korea. We employ a difference-in-differences estimation strategy by comparing the differential effects of the H1N1 outbreak on the confirmed cases of diseases which can be prevented by preventive behaviors (e.g., intestinal infections) and the cases of diseases which cannot (e.g., injuries). Using unique administrative data from South Korea's National Health Insurance Service (NHIS), we find that the exogenous increase in health risk reduced the incidence of intestinal infections compared to the injuries during the H1N1 influenza outbreak. The reduction was the most substantial among children under five years of age, with a 25.4% decline in cases of intestinal infections relative to injuries. Our findings are robust across various alternative specifications. We provide suggestive evidence that active adoption of preventive behaviors is one of the channels underlying the unexpected decrease in diarrhea cases. The effects, however, faded away shortly after the end of the pandemic and did not last in the long run.

The Relationship Between Types of Smartphone Use, Digital Literacy, and Smartphone Addiction in the Elderly.

There is limited understanding of which specific factors relate to smartphone addiction in the elderly. The aim of this study was to examine the relationship between types of smartphone use, digital literacy, and smartphone addiction in the elderly. It used data from a survey on smartphone overdependence by the South Korea National Information Society Agency in 2019. Participants were 3,121 older people (1,627 males, 1,494 females; mean age=63.83 [standard deviation=2.88 years]). We conducted hierarchical multiple regression analysis. The results of a hierarchical multiple regression analysis indicated that smartphone usage time was positively related to smartphone addiction. Entertainment-seeking and life service types of smartphone use, and digital literacy were positively associated with smartphone addiction. Conversely, smartphone use for information-seeking and communication-seeking was negatively related to smartphone addiction. This study suggests that it is necessary to understand different types of smartphone uses in the elderly and to educate the elderly on digital literacy to prevent smartphone addiction. In future studies, it will be necessary to re-confirm the relationship between smartphone usage type, digital literacy, and smartphone addiction in the elderly (including participants in their 70s or older).

Association between periodontal disease, tooth extraction, and medication-related osteonecrosis of the jaw in women receiving bisphosphonates: A national cohort-based study.

We investigated whether periodontal diseases contribute to the development of medication-related osteonecrosis of the jaw (MRONJ) in addition to tooth extraction, which is a major risk factor for MRONJ occurrence. This retrospective, nationwide cohort study was performed using South Korea's National Health Insurance Service database on women aged>50 years who took bisphosphonates for at least 1 year between 2010 and 2015. MRONJ, periodontal disease, and tooth extraction were defined using the claims data. Among the 27,168 patients analyzed, the incidence of confirmed MRONJ was significantly higher in the periodontal disease group (0.58%) than in the nonperiodontal disease group (0.31%). While extraction alone showed an increased risk of MRONJ development (hazard ratio [HR]=1.61, 95% confidence interval [CI]: 0.74-3.52), periodontal disease without tooth extraction also indicated a similar risk (HR=1.68, 95% CI: 0.86-3.28); when a history of both periodontal disease and tooth extraction was present, the HR significantly increased to 2.55 (95% CI: 1.41-4.64). The risk of MRONJ increased significantly when tooth extraction was performed in patients diagnosed with periodontal disease; therefore, periodontal diseases should be proactively managed in patients taking bisphosphonates.

Soil carbon storage and its economic values of inland wetlands in Korea

Due to the importance of wetlands as a global carbon pool, explicit research on and management of the carbon storage of wetlands have drawn much attention. Within a single climatic zone, South Korea has various types of inland wetlands such as tidal salt marshes, freshwater lakes, rivers and peatlands, thereby providing an excellent platform for scientific investigation to identify patterns and key controlling factors of carbon budget in different inland wetlands. We estimated the amount of soil organic carbon (SOC) of 2444 inland wetlands in South Korea by cluster analysis and Monte-Carlo simulation using data from South Korea's National Wetland Inventory and their economic values by literature review. In addition, we identified key controlling factors that are closely related to SOC of 34 inland wetlands by correlation analysis and ANOVA test. We found that the total SOC stock of inland wetlands in South Korea is 16.3 ± 0.4 TgC (22.3 ± 0.6 kgC m−2), which is 5.3–5.5% of the total SOC stock of the country, and the annual carbon sequestration rate is 60.7 ± 9.8 gC m−2 yr−1. The economic value of the total SOC stock is 2.0 ± 0.1 billion USD (2.8 ± 0.1 USD m−2), and that of the annual sequestration rate is 5.5 ± 0.9 million USD yr−1 (7.5 ± 1.2 10−3 USD m−2 yr−1). The mean atmospheric temperature and soil characteristics including water content, total nitrogen and electrical conductivity showed positive correlations with SOC, suggesting the importance of hydrology and water chemistry as key determinants of SOC. In addition, inland wetlands with different dominant plant species showed significantly different SOC, probably because primary production and chemical composition of vegetation are strongly associated with carbon input into wetlands. However, annual precipitation and soil pH showed no correlation with SOC. Our results demonstrate that the carbon budget of inland wetlands in South Korea is considerable, and its economic value is closely related to characteristics of soil and vegetation.

Secular Trends of Incidence, Prevalence, and Healthcare Economic Burden in ANCA-Associated Vasculitis: An Analysis of the 2002–2018 South Korea National Health Insurance Database

ObjectivesThe incidence and prevalence of AAV in Asia remain poorly understood, especially in a nationwide setting. This study investigated the incidence, prevalence, and healthcare burden of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in South Korea by analyzing a national database.MethodsThis study included patients with AAV identified from the National Health Insurance Service Database of South Korea from 2002 to 2018. Patients were diagnosed with AAV in a general or tertiary hospital and were registered in the individual payment beneficiaries program or were prescribed glucocorticoids. A calendar-based meteorological definitions were adopted to assess the differences in the incidence of AAV according to season. The average healthcare expenditure and patient outcomes of mortality and end-stage renal disease (ESRD) in patients with AAV were compared to 1:10 age, sex and residential area matched controls.ResultsA total of 2,113 patients [708, 638, and 767 with microscopic polyangiitis (MPA), granulomatosis with polyangiitis, and eosinophilic granulomatosis with polyangiitis, respectively] were identified. The annual incidence and prevalence of AAV increased continuously, and MPA being the most common disease subtype after 2015. The highest incidence and prevalence of AAV was 0.48/100,000 person-years (PY) and 2.40/100,000 PY in 2017 and 2018, respectively. There were no significant differences in monthly and seasonal incidence of AAV. The average expense of medical care, overall mortality, and ESRD rates of patients with AAV were higher in patients with AAV than in controls, especially in the case of MPA.ConclusionAn increasing trend of AAV diagnosis observed is consistent with the evidence that AAV is more common in recent years; however, a relatively lower incidence and prevalence was observed compared to that in Western countries. The higher medical cost and rates of mortality and ESRD in AAV emphasize the early recognition and implementation of optimal treatment for these patients.

The cost- effectiveness of early dental visit in infants and toddlers focused on regional deprivation in South Korea: A retrospective cohort study.

The aims of this study are to evaluate the cost-effectiveness of early dental visits (EDVs) and to investigate how regional deprivation impacts the economic evaluation. This study used the South Korea National Health Insurance database, which included medical claim data and voluntary-based oral examination data. The subjects of this study included whole participants for oral examinations for infants and toddlers of the National Health Insurance Corporation. A retrospective cohort study was designed and measured all oral treatments, costs, and number of visits for 208,969 children (experimental group, 101,768; non- experimental group, 107,201) who underwent oral examination for infants and toddlers from 2007 to 2014. The cost-effectiveness was measured using the incremental cost-effectiveness ratio, and the T-health index was used as the measurement for effectiveness. In addition, the difference in the effect according to the level of regional deprivation was confirmed. The findings of this study showed that EDVs were cost-effective and that children who participated in EDVs had better oral health (T-health-2 index difference 0.32 point in most deprived regions) and needed 5 USD less costly dental treatments than those who did not have EDVs. The cost-effectiveness of EDVs varied according to the level of regional deprivation and was the highest in the most deprived regions. The study findings suggested that the provision of oral examination for infants and toddlers was a cost-effective dental policy. Additionally, EDVs were more effective in children who resided in the most deprived regions, a finding that will lead to the development of policy intervention to improve dental care despite spatial inequality for disadvantaged population groups. Regarding the distribution of dental hospitals/clinics, incentive based dental polices for either dental providers or patients are needed that will assure the delivery of dental care despite spatial inequality.

Risk and Risk Factors for Postpartum Type 2 Diabetes Mellitus in Women with Gestational Diabetes: A Korean Nationwide Cohort Study.

BackgroundThere are differences in risk and risk factor findings of postpartum type 2 diabetes mellitus (T2DM) after gestational diabetes depending on study design and subjects of previous studies. This study aimed to assess these risk and risk factors more accurately through a population-based study to provide basic data for prevention strategies.MethodsThis open retrospective cohort included data of 419,101 women with gestational diabetes and matched 1,228,802 control women who delivered between 2004 and 2016 from the South Korea National Health Information Database of the National Health Insurance Service. Following 14 (median 5.9) years of follow-up, the incidence and hazard ratio (HR) of postpartum T2DM were evaluated using Kaplan-Meier curves and Cox proportional regression models.ResultsThe incidence and HR of postpartum T2DM in women with gestational diabetes (compared to women without gestational diabetes) after the 14-year follow-up was 21.3% and 2.78 (95% confidence interval [CI], 2.74 to 2.82), respectively. Comorbid obesity (body mass index [BMI] ≥25 kg/m2) increased postpartum T2DM risk 7.59 times (95% CI, 7.33 to 7.86). Significant risk factors for postpartum T2DM were fasting glucose level, BMI, age, family history of diabetes, hypertension, and insulin use during pregnancy.ConclusionThis population-based study showed higher postpartum T2DM risk in women with gestational diabetes than in those without, which was further increased by comorbid obesity. BMI and fasting glucose level were important postpartum risk factors. The management of obesity and glycemic control may be important strategies to prevent the incidence of diabetes after delivery.