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Abstract Aims Protein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are novel lipid-lowering agents used in patients with cardiovascular disease. Despite reassuring safety data from pivotal trials, increasing evidence from real-world studies suggests that PCSK9i increase the risk of bacterial and viral infections. Therefore, this study aimed to identify signals of infection-related adverse events (AEs) associated with PCSK9i. Methods We performed an observational pharmacovigilance study using the World Health Organization’s VigiBase, recorded up to December 2022. We included individual case safety reports (ICSRs) of PCSK9 inhibitors, alirocumab and evolocumab, and compared them with those of other drugs. Infection-related ICSRs were retrieved from the Medical Dictionary for Regulatory Activities System Organ Class ‘infections and infestations.’ Results Among 114,293 reports (258,099 drug–AE pairs) related to PCSK9 inhibitors, 54% included female patients, 41% included patients aged ≥65 years, and 82% included patients who received evolocumab. Additionally, beyond AEs recognized by regulatory authorities, organ infections such as influenza (reporting odds ratio [ROR] 2.89, 95% confidence interval [CI] 2.74–3.05), gastric infections (ROR 2.47, 95% CI 1.63–3.75), and kidney infections (ROR 1.36, 95% CI 1.06–1.73) were observed. Sensitivity analysis indicated a heightened risk of infection-related AEs associated with PCSK9i regardless of the specific drug type. Conclusions In addition to the labelled respiratory infections, six infection-related symptoms in the gastrointestinal, urinary, and renal organs were identified. Our findings support the need for systematic surveillance of infections among PCSK9i users.

Abstract This study aims to figure out the worldwide prevalence of anticancer therapy-associated acute kidney injury (AKI) and tubulointerstitial nephritis (TIN) and the relative risk of each cancer drug. We conducted an analysis of VigiBase, the World Health Organization pharmacovigilance database, 1967–2023 via disproportionate Bayesian reporting method. We further categorized the anticancer drugs into four groups: cytotoxic therapy, hormone therapy, immunotherapy, and targeted therapy. Reporting odds ratio (ROR) and information component (IC) compares observed and expected values to investigate the associations of each category of anticancer drugs with AKI and TIN. We identified 32,722 and 2056 reports (male, n = 17,829 and 1,293) of anticancer therapy-associated AKI and TIN, respectively, among 4,592,036 reports of all-drug caused AKI and TIN. There has been a significant increase in reports since 2010, primarily due to increased reports of targeted therapy and immunotherapy. Immunotherapy exhibited a significant association with both AKI (ROR: 8.92; IC0.25: 3.06) and TIN (21.74; 4.24), followed by cytotoxic therapy (7.14; 2.68), targeted therapy (5.83; 2.40), and hormone therapy (2.59; 1.24) for AKI, and by cytotoxic therapy (2.60; 1.21) and targeted therapy (1.54; 0.61) for TIN. AKI and TIN were more prevalent among individuals under 45 years of age, with a female preponderance for AKI and males for TIN. These events were reported in close temporal relationship after initiation of the respective drug (16.53 days for AKI and 27.97 days for TIN), and exhibited a high fatality rate, with 23.6% for AKI and 16.3% for TIN. These findings underscore that kidney-related adverse drug reactions are of prognostic significance and strategies to mitigate such side effects are required to optimize anticancer therapy.

Abstract Lazertinib is a recently developed third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors used for patients with advanced EGFR T790M-positive non-small-cell lung cancer. We evaluated the effectiveness of lazertinib compared with osimertinib using an external control. We obtained individual patient data for the lazertinib arm from the LASER201 trial and the osimertinib arm from registry data at the Samsung Medical Center. In total, 75 and 110 patients were included in the lazertinib and osimertinib groups, respectively. After propensity score matching, each group had 60 patients and all baseline characteristics were balanced. The median follow-up duration was 22.0 and 29.6 months in the lazertinib and osimertinib group, respectively. The objective response rate (ORR) were 76.7% and 86.7% for lazertinib and osimertinib, respectively (p = 0.08). The median progression-free survival (PFS) was 12.3 months (95% confidence interval [CI] 9.5–19.1) and 14.4 months (95% CI 11.8–18.1) for the lazertinib and osimertinib group, respectively (hazard ratio [HR] 0.97; 95% CI 0.64–1.45, p = 0.86). The median overall survival with lazertinib was not reached and that with osimertinib was 29.8 months (HR 0.44; 95% CI 0.25–0.77, p = 0.005). Our study suggests that lazertinib has an ORR and PFS comparable to those of osimertinib and has the potential for superior survival benefits.

Abstract Chimeric antigen receptor T-cell (CAR-T) therapies are a paradigm-shifting therapeutic in patients with hematological malignancies. However, some concerns remain that they may cause serious cardiovascular adverse events (AEs), for which data are scarce. In this study, gradient boosting machine algorithm-based model was fitted to identify safety signals of serious cardiovascular AEs reported for tisagenlecleucel in the World Health Organization Vigibase up until February 2024. Input dataset, comprised of positive and negative controls of tisagenlecleucel based on its labeling information and literature search, was used to train the model. Then, we implemented the model to calculate the predicted probability of serious cardiovascular AEs defined by preferred terms included in the important medical event list from European Medicine Agency. There were 467 distinct AEs from 3,280 safety cases reports for tisagenlecleucel, of which 363 (77.7%) were classified as positive controls, 66 (14.2%) as negative controls, and 37 (7.9%) as unknown AEs. The prediction model had area under the receiver operating characteristic curve of 0.76 in the test dataset application. Of the unknown AEs, six cardiovascular AEs were predicted as the safety signals: bradycardia (predicted probability 0.99), pleural effusion (0.98), pulseless electrical activity (0.89), cardiotoxicity (0.83), cardio-respiratory arrest (0.69), and acute myocardial infarction (0.58). Our findings underscore vigilant monitoring of acute cardiotoxicities with tisagenlecleucel therapy.

Purpose Montelukast is used extensively in children and adolescents for allergic rhinitis and asthma. However, concerns have been raised regarding the increased risk of neuropsychiatric adverse events (NPAEs) associated with montelukast use. Therefore, our case-crossover study was conducted to observe whether there is an increased risk of NPAEs associated with montelukast use in children and adolescents.Materials and methods A population-based case-crossover study using the customised Health Insurance Review and Assessment (HIRA) dataset was conducted. Paediatric patients aged between 0 and 19 years diagnosed with allergic rhinitis and/or asthma with a history of at least one montelukast prescription between 1 January 2018 and 31 December 2021 were included. Exposure to montelukast was assessed during 3-, 7-, 14-, 28- and 56-day hazard periods prior to each patient’s NPAE. Stratified analyses according to age group, gender and season for the risk of NPAEs associated with montelukast use in the previous 7 days and 14 days were performed, respectively. Conditional logistic regression analysis was used to calculate adjusted ORs (aORs) with their corresponding 95% CIs, adjusting for concomitant medications.Results A total of 161 386 paediatric patients was identified. An increased risk of NPAEs associated with montelukast was found in all time window periods, including 3-day (aOR 1.28, 95% CI 1.24 to 1.32), 7-day (aOR 1.29, 95% CI 1.26 to 1.33), 14-day (aOR 1.34, 95% CI 1.31 to 1.37), 28-day (aOR 1.38, 95% CI 1.36 to 1.41) and 56-day (aOR 1.21, 95% CI 1.19 to 1.22) preceding hazard periods compared with use in the four control periods.Conclusion Children and adolescents with allergic rhinitis and/or asthma should be prescribed montelukast with caution considering clinical benefits.

The COVID-19 Vaccine Safety Research Committee (CoVaSC) was established in November 2021 to address the growing need for independent, in-depth scientific evidence on adverse events (AEs) following coronavirus disease 2019 (COVID-19) vaccination. This initiative was requested by the Korea Disease Control and Prevention Agency and led by the National Academy of Medicine of Korea. In September 2022, the COVID-19 Vaccine Safety Research Center was established, strengthening CoVaSC’s initiatives. The center has conducted various studies on the safety of COVID-19 vaccines. During CoVaSC’s second research year, from September 29, 2022 to July 19, 2023, the center was restructured into 4 departments: Epidemiological Research, Clinical Research, Communication & Education, and International Cooperation & Policy Research. Its main activities include (1) managing CoVaSC and the COVID-19 Vaccine Safety Research Center, (2) surveying domestic and international trends in AE causality investigation, (3) assessing AEs following COVID-19 vaccination, (4) fostering international collaboration and policy research, and (5) organizing regular fora and training sessions for the public and clinicians. Causality assessments have been conducted for 27 diseases, and independent research has been conducted after organizing ad hoc committees comprising both epidemiologists and clinical experts on each AE of interest. The research process included protocol development, data analysis, interpretation of results, and causality assessment. These research outcomes have been shared transparently with the public and healthcare experts through various fora. The COVID-19 Vaccine Safety Research Center plans to continue strengthening and expanding its research activities to provide reliable, high-quality safety information to the public.

Abstract Background Several neurological manifestations shortly after a receipt of coronavirus infectious disease 2019 (COVID-19) vaccine have been described in the recent case reports. Among those, we sought to evaluate the risk of encephalitis and meningitis after COVID-19 vaccination in the entire South Korean population. Methods We conducted self-controlled case series (SCCS) analysis using the COVID-19 immunization record data from the Korea Disease Control Agency between February 2021 and March 2022, linked with the National Health Insurance Database between January 2021 and October 2022. We retrieved all medical claims of adults aged 18 years or older who received at least one dose of COVID-19 vaccines (BNT162b2, mRNA-1273, ChAdOx1-S, or Ad26.COV2.S), and included only those who had a diagnosis record for encephalitis or meningitis within the 240-day post-vaccination period. With day 0 defined as the date of vaccination, risk window was defined as days 1–28 and the control window as the remainder period excluding the risk windows within the 240-day period. We used conditional Poisson regression to estimate the incidence rate ratios (IRR) with 95% confidence intervals (CI), stratified by dose and vaccine type. Results From 129,956,027 COVID-19 vaccine doses administered to 44,564,345 individuals, there were 251 and 398 cases of encephalitis and meningitis during the risk window, corresponding to 1.9 and 3.1 cases per 1 million doses, respectively. Overall, there was an increased risk of encephalitis in the first 28 days of COVID-19 vaccination (IRR 1.26; 95% CI 1.08–1.47), which was only significant after a receipt of ChAdOx1-S (1.49; 1.03–2.15). For meningitis, no increased risk was observed after any dose of COVID-19 vaccine (IRR 1.03; 95% CI 0.91–1.16). Conclusions Our findings suggest an overall increased risk of encephalitis after COVID-19 vaccination. However, the absolute risk was small and should not impede COVID-19 vaccine confidence. No significant association was found between the risk of meningitis and COVID-19 vaccination.

Abstract Although functional dyspepsia (FD) is a common functional gastroduodenal disorder with a high socioeconomic burden, little is known about its global prevalence. Thus, we performed a comprehensive study to estimate long-term trends in the prevalence of FD. We searched PubMed/MEDLINE, Embase, and Google Scholar from 1990 to 2022 for population-based studies that reported the prevalence of FD in adults (≥ 18 years old) according to Rome I, II, III, or IV criteria. The prevalence of FD was extracted from included studies to obtain pooled prevalence with 95% confidence intervals (CI) and 95% prediction intervals. Subgroup analysis was performed according to certain characteristics, including geographic region. A total of 44 studies met the eligibility criteria, including 256,915 participants from 40 countries across six continents. The overall global pooled prevalence of FD was 8.4% (95% CI 7.4–.9.5). The prevalence was the highest in Rome I (11.9%; 95% CI 5.1–25.4) and lowest in Rome IV (6.8%; 95% CI 5.8–7.9). Developing countries showed a higher prevalence than developed countries (9.1% versus 8.0%), and prevalence was higher in women, irrespective of the definition used (9.0% versus 7.0%). The pooled prevalence gradually decreased from 1990 to 2020 (12.4% [8.2–18.3] in 1990–2002 versus 7.3% [6.1–8.7] in 2013–2020). The prevalence of FD differs by country, economic status, geographical region, and sex, and the global prevalence has been gradually declining. Despite the heterogeneity of sample population, our study estimates the current global burden of FD and provides information to heath care policy decisions.

Patients with inflammatory bowel diseases (IBDs), including ulcerative colitis (UC) and Crohn's disease (CD), often have concomitant mental disorders such as depression and anxiety. Therefore, a bidirectional approach involving the gut and brain axes is necessary for the prevention and treatment thereof. In this study, we explored the potential of Poncirus trifoliata extract (PT), traditionally known for its neuroprotective effects against gastrointestinal diseases, as a natural treatment agent for IBD in a dextran sulfate sodium (DSS)-induced colitis model. Oral administration of PT ameliorated weight loss and inflammatory responses in mice with DSS-induced colitis. Furthermore, PT treatment effectively restored the colon length and ameliorated enterocyte death by inhibiting DSS-induced reactive oxygen species (ROS)-mediated necroptosis. The main bioactive components of PT, poncirin and naringin, confirmed using ultra-performance liquid chromatography-quadrupole time-of-flight (UPLC-qTOF), can be utilized to regulate necroptosis. The antidepressant-like effects of PT were confirmed using open field test (OFT) and tail suspension test (TST). PT treatment also restored vascular endothelial cell integrity in the hippocampus. In the Cornu Ammonis 1 (CA1) and dentate gyrus (DG) regions of the hippocampus, PT controlled the neuroinflammatory responses of proliferated microglia. In conclusion, PT, which contains high levels of poncirin and naringin, has potential as a bidirectional therapeutic agent that can simultaneously improve IBD-associated intestinal and mental disorders.

Abstract Introduction To estimate herpes zoster (HZ) incidence rate (IR) and economic burden in individuals with immunocompromised conditions and autoimmune diseases (IC/AID) in the Republic of Korea (ROK). Methods The nationwide Health Insurance Review and Assessment Service database was used to identify HZ cases from 2016 to 2020 in ROK. HZ and non-HZ IC/AID cases were matched 1:3 using age, sex, institution, Charlson comorbidity index, IC/AID, and index date. Annual HZ IRs/1000 persons and 1-year HZ-associated all-cause direct medical costs for IC/AID cases were calculated. Results Among 65,976 individuals with IC/AID (mean age 57.14 years [standard deviation 14.1]; 64.94% female), annual HZ IR (95% confidence interval) fluctuated from 2016 to 2020, averaging 23.41/1000 persons (22.21–24.62) and was higher in women (26.85 [25.40–28.31]) than men (18.96 [18.03–19.89]). IRs were highest in individuals aged ≥ 50 years, and in those with transplants (including solid organ and hematopoietic stem cell transplants; 37.12 [35.45–38.79]) and hemato-oncology conditions (35.5 [31.6–39.3]). Mean 12-month all-cause direct medical costs were higher in individuals with IC/AID and HZ (4,759,671 Korean Republic won [KRW]; approximately 4046 United States dollar [USD; according to the 2020 conversion rate from UNCTAD; 1 KRW = 0.00085 USD]) than those without HZ (3,786,658 KRW; 3219 USD). Conclusion Individuals with IC/AID have a substantial disease and economic burden from HZ in ROK, highlighting the need for appropriate HZ prevention measures in the IC/AID population. Plain Language Summary

Objective To investigate the association between the use of limaprost and the risk of bleeding. Methods A self-controlled case series analysis was conducted using the National Health Insurance Service-National Sample Cohort database in South Korea. We identified patients aged 18 years or older who had at least one prescription of limaprost and were diagnosed with at least one case of bleeding between 2003 and 2019. The incidence rate ratio (IRR) of bleeding was calculated by dividing the incidence rate in the exposed period to limaprost by that in the unexposed period and adjusted for age using conditional Poisson regression model. Results Among 72,860 patients with limaprost prescriptions and bleeding diagnoses, there were 184,732 events of bleeding. After adjusting for age, the IRR was 1.47 (95% confidence interval [CI], 1.43–1.50), wherein the IRR was the highest during the 0–7 days after limaprost initiation (IRR, 2.11; 95% CI, 2.03–2.18). Risk of bleeding was higher when limaprost was concomitantly used with antithrombotics or other drugs for spinal stenosis treatment, and when higher daily doses of limaprost were administered. Conclusion Our findings suggest that the risk of bleeding increased by 1.5-fold in periods of limaprost exposure compared to unexposed periods, with particularly higher risks observed during the first week after limaprost initiation, with concomitant drugs related to bleeding, and with a higher daily dose. A careful risk-benefit assessment is warranted when initiating limaprost, especially when administered with other medications or in higher daily doses.

A retrospective cohort study was conducted to examine trends in the incidence and burden of pertussis among adults ≥50 years in South Korea, with/without pre-existing chronic obstructive pulmonary disease (COPD) or asthma. The nationwide Health Insurance Review and Assessment Service (HIRA) database was used to identify patients ≥50 years diagnosed with pertussis (2009–2018). Mean annual incidence of pertussis per 100 000 persons and overall mean incidence rate ratios (IRR) were calculated for patients with pre-existing COPD or asthma versus those with neither. Incremental healthcare costs (all-cause and pertussis-related) and healthcare utilisation (number of outpatient visits, emergency room visits, and number and length of hospitalisations) up to 12 months after, compared to 3 months before pertussis diagnosis, were also measured for each group (matched on sex, age, and Charlson Comorbidity Index). Of 1011 pertussis cases, 175 had asthma, 96 had COPD (not mutually exclusive), and 796 had neither. Overall mean pertussis incidence was 2.5, 3.4, and 0.5 for adults with pre-existing COPD, asthma, and those with neither. IRR (95% confidence interval) of pertussis for adults with pre-existing COPD and asthma was 4.9 (4.0–‍6.1) and 6.7 (5.7–7.9). Both COPD-pertussis and asthma-pertussis groups had higher mean incremental all-cause costs and length of hospitalisations than the general-pertussis group 3 months following pertussis diagnosis. In conclusion, individuals ≥50 years in South Korea with pre-existing COPD or asthma were at an increased risk of being diagnosed with pertussis and had higher healthcare resource utilisation than those without these conditions.

Abstract Background Nonpersistence in anticoagulation therapy is common and associated with undesirable clinical outcomes in patients with venous thromboembolism (VTE). Methods We investigated preceding clinical events of treatment nonpersistence (e.g., switching, discontinuing, or restarting) in VTE patients with and without active cancer using Korean claims database. Results Clinically significant events including thromboembolic events, hepatic function change and surgery preceded treatment nonpersistence, but heterogeneous distributions of clinical events were observed in the presence of active cancer. Patients with active cancer had a low rate of clinical events preceding treatment nonpersistence, and new active cancer diagnosis in the nonactive cancer group was most common before the switch to parenteral anticoagulants from warfarin or non‐vitamin K antagonist oral anticoagulants (NOACs). Conclusion These findings suggest that clinically significant events can precede treatment nonpersistence and largely paralleled current guidelines for patients with VTE, whereas heterogeneous distributions of clinical events were observed in the presence of active cancer.

Objective To investigate the risk of cardiovascular events associated with commonly used dual and triple therapies of evogliptin, a recently introduced dipeptidyl peptidase-4 inhibitor (DPP4i), for managing type 2 diabetes in routine clinical practice.Design A retrospective cohort study.Setting Korean Health Insurance Review and Assessment database.Participants Patients who initiated metformin-based dual therapy and metformin+sulfonylurea-based triple therapy in South Korea from 2014 to 2018.Interventions Initiation of combination therapy with evogliptin.Primary and secondary outcome measures Hazards of cardiovascular events, a composite endpoint of myocardial infarction, heart failure and cerebrovascular events, and its individual components. Cox proportional hazards model with propensity score-based inverse probability of treatment weighting were used to estimate HRs and 95% CIs.Results From the dual and triple therapy cohorts, 5830 metformin+evogliptin users and 2198 metformin+sulfonylurea+evogliptin users were identified, respectively. Metformin+evogliptin users, as compared with metformin+non-DPP4i, had a 29% reduced risk of cardiovascular events (HR 0.71, 95% CI 0.62 to 0.82); HRs for individual outcomes were cerebrovascular events (0.71, 95% CI 0.53 to 0.95), heart failure (0.70, 95% CI 0.59 to 0.82), myocardial infarction (0.89, 95% CI 0.60 to 1.31). Metformin+sulfonylurea+evogliptin users, compared with metformin+sulfonylurea+non-DPP4i, had a 24% reduced risk of cardiovascular events (0.76, 95% CI 0.59 to 0.97); HRs for individual outcomes were myocardial infarction (0.57, 95% CI 0.27 to 1.19), heart failure (0.74, 95% CI 0.55 to 1.01), cerebrovascular events (0.96, 95% CI 0.61 to 1.51).Conclusions These findings suggest that dual or triple therapies of evogliptin for the management of type 2 diabetes in routine clinical practice present no cardiovascular harms, but could alternatively offer cardiovascular benefits in this patient population.

Abstract Disproportionate impact of COVID-19 on socioeconomic and behavioral variables may have impacted the prevalence of diabetes. We utilized nationwide long-term serial study from the 2009 to 2021 Korea Community Health Survey (KCHS). We explored national and regional prevalence and trends of diabetes according to the socioeconomic and behavioral factors before and during the pandemic. Also, we interpreted which groups became more vulnerable to the prevalence of diagnosed diabetes during the pandemic. A total of 2,971,349 adults aged (19 to 39, 40 to 59, and ≥ 60 years) were included in the analysis. The prevalence of diagnosed diabetes increased slowly during the pandemic (11.6% [95% CI 11.5–11.7] in 2020 and 12.4% [95% CI 12.3–12.6] in 2021), compared to the pre-pandemic era (7.9% [95% CI 7.8–7.9] in 2009–2011 and 11.3% [95% CI 11.3–11.4] in 2018–2019). Also, women, low-income group, low-educational group, and infrequent walking group showed less prevalence of diagnosed diabetes than the others. The diabetic population increased slowly than expected during the pandemic. The pandemic seems to contribute to an unanticipated increase in under-diagnosis of diabetes among the already minority. This study may suggest reinforcing access to healthcare services among the minority during the pandemic.

Abstract Background Emulating randomized controlled trials (RCTs) by real-world evidence (RWE) studies would benefit future clinical and regulatory decision-making by balancing the limitations of RCT. We aimed to evaluate whether the findings from RWE studies can support regulatory decisions derived from RCTs of non-vitamin K antagonist oral anticoagulants (NOACs) in patients with venous thromboembolism (VTE). Methods Five landmark trials (AMPLIFY, RE-COVER II, Hokusai-VTE, EINSTEIN-DVT, and EINSTEIN-PE) of NOACs were emulated using the South Korean nationwide claims database (January 2012 to August 2020). We applied an active comparator and new-user design to include patients who initiated oral anticoagulants within 28 days from their VTE diagnoses. The prespecified eligibility criteria, exposure (each NOAC, such as apixaban, rivaroxaban, dabigatran, and edoxaban), comparator (conventional therapy, defined as subcutaneous heparin followed by warfarin), and the definition of outcomes from RCTs were emulated as closely as possible in each separate emulation cohort. The primary outcome was identical to each trial, which was defined as recurrent VTE or VTE-related death. The safety outcome was major bleeding. Propensity score matching was conducted to balance 69 covariates between the exposure groups. Effect estimates for outcomes were estimated using the Mantel–Haenszel method and Cox proportional hazards model and subsequently compared with the corresponding RCT estimates. Results Compared to trial populations, real-world study populations were older (range: 63–69 years [RWE] vs. 54–59 years [RCT]), with more females (55–60.5% vs. 39–48.3%) and had a higher prevalence of active cancer (4.2–15.4% vs. 2.5–9.5%). The emulated estimates for effectiveness outcomes showed superior effectiveness of NOAC (AMPLIFY: relative risk 0.81, 95% confidence interval 0.70–0.94; RE-COVER II: hazard ratio [HR] 0.60, 0.37–0.96; Hokusai-VTE: 0.49, 0.31–0.78; EINSTEIN-DVT: 0.54, 0.33–0.89; EINSTEIN-PE: 0.50, 0.34–0.74), when contrasted with trials that showed non-inferiority. For safety outcomes, all emulations except for AMPLIFY and EINSTEIN-DVT yielded results consistent with their corresponding RCTs. Conclusions This study revealed the feasibility of complementing RCTs with RWE studies by using claims data in patients with VTE. Future studies to consider the different demographic characteristics between RCT and RWE populations are needed.

Abstract Benefits of breastfeeding for both the mother and the child are well established, but a comprehensive and robust study to investigate the protective effect of breastfeeding and attenuated time effect stratified by cause of morbidity are lacking. This study is based on the nationwide birth cohort in Korea that includes data on all infants born from 2009 to 2015. Of 1,608,540 children, the median follow-up period was 8.41 years (interquartile range, 6.76-10.06). When compared to children with fully formula feeding, the hospital admission rate was 12% lower in those with partially breastfeeding and 15% lower in those with exclusive breastfeeding. The apparent protective effect of breastfeeding was reduced with increasing age. Our study provides potential evidence of the beneficial association of breastfeeding on subsequent hospital admissions. The protective effect declined over time as the children grew older. Encouraging any breastfeeding for at least the first 6 months among infants is an important public health strategy to improve overall child health.

Background/Purpose(s): Bedaquiline and delamanid were recently approved for multidrug resistant tuberculosis (MDR-TB). Bedaquiline carries a black box warning of increased risk of death compared to the placebo arm, and there is a need to establish the risks of QT prolongation and hepatotoxicity for bedaquiline and delamanid. Methods: We retrospectively analyzed data of MDR-TB patients retrieved from the South Korea national health insurance system database (2014–2020) to assess the risks of all-cause death, long QT-related cardiac event, and acute liver injury associated with bedaquiline or delamanid, compared with conventional regimen. Cox proportional hazards models were used to estimate hazard ratios (HR) with 95% confidence intervals (CI). Stabilized inverse probability of treatment weighting based on propensity score was used to balance characteristics between the treatment groups. Results: Of 1998 patients, 315 (15.8%) and 292 (14.6%) received bedaquiline and delamanid, respectively. Compared with conventional regimen, bedaquiline and delamanid did not increase risk of all-cause death at 24-month (HR 0.73 [95% CI, 0.42–1.27] and 0.89 [0.50–1.60], respectively). Bedaquiline-containing regimen increased risk of acute liver injury (1.76 [1.31–2.36]), while delamanid-containing regimen increased risk of long QT-related cardiac events (2.38 [1.05–3.57]) within 6 months of treatment. Conclusion: This study adds to the emerging evidence refuting the higher mortality rate observed in the bedaquiline trial population. Association between bedaquiline and acute liver injury needs careful interpretation considering for other background hepatotoxic anti-TB drugs. Our finding on delamanid and long QT-related cardiac events suggest careful risk-benefit assessment in patients with pre-existing cardiovascular disease.

Background: To eliminate tuberculosis (TB), World Health Organization (WHO) initiated “The End TB Strategy” with the goal of a 95% reduction in deaths. While many resources are contributed to eradicating TB, a substantial number of TB patients are still unlikely to receive timely treatment. Thus, we aimed to measure healthcare delay and its association with clinical outcomes from 2013 to 2018. Methods: We conducted a retrospective cohort study using linked data of the National Tuberculosis Surveillance Registry and the health insurance claims data of South Korea. We included incident TB patients, and healthcare delay was defined as the period between the first medical visit with TB-related symptoms and the initiation of an anti-TB regimen. We described the distribution of healthcare delay, and the study population was classified into two groups with mean as a cutoff. The association between healthcare delay and clinical outcomes (all-cause mortality, pneumonia, progression to multi/extensively drug-resistant, intensive care unit admission, and mechanical ventilation use) was evaluated using the Cox proportional hazard model. Several stratified and sensitivity analyses were also conducted. Results: Among 39,747 patients with pulmonary TB, mean healthcare delay was 42.3 days and delayed and non-delayed groups, classified by mean (or average), were 10,680 (26.9%) and 29,067 (73.1%), respectively. Healthcare delay was associated with an increased risk of all-cause mortality (HR 1.10, 95% CI 1.03–1.17), pneumonia (HR 1.13, 95% CI 1.09–1.18), and mechanical ventilation use (HR 1.15, 95% CI 1.01–1.32). We also observed the duration-response of healthcare delay. Stratified analyses showed patients with respiratory diseases were at higher risk, and consistent results were observed in sensitivity analyses. Conclusions: We observed a substantial number of patients experiencing healthcare delays, and it was associated with the deterioration of clinical outcomes. Our findings suggest that attention from authorities and healthcare professionals is needed to attenuate the preventable burden caused by TB through timely treatment.

In this study, future precipitation and drought in the Ca river basin, Vietnam, were projected based on an ensemble of 27 CMIP6 models for four climate change scenarios. The impact of climate change on precipitation and drought was investigated. Monthly precipitation observation data were adjusted using the bias correction method. To detect drought events, the Standard Precipitation Index (SPI) was employed. Changes in drought were assessed using SPI3, SPI6, and SPI12. Although the amount of annual total precipitation slightly increased, the drought events may become more severe. There is a high likelihood of increased drought intensity and severity in Vietnam due to climate change. The frequency of droughts is likely to change depending on the location and climate change scenario. We found that the frequency and severity of droughts may be altered depending on the window size of SPI. The short-term drought events will be more frequent and severe, and long-term drought events will become more severe in the Ca river basin.

Abstract Background Given the cumulative evidence on the effectiveness of sodium-glucose cotransporter 2 inhibitors (SGLT2is) on chronic heart failure, demand is emerging for further information on their effects in patients who are hospitalized for acute heart failure. However, there is still limited evidence about the class effect of SGLT2is on acute heart failure. We investigated whether initiating treatment with SGLT2is after an episode of acute heart failure reduces the risks of post-discharge heart failure readmission or cardiovascular mortality among patients with type 2 diabetes. Methods A retrospective cohort study was conducted in a cohort of patients with type 2 diabetes who hospitalized for heart failure, using Korean Health Insurance Review & Assessment database (2015–2020). The exposure was defined as initiation of SGLT2is during hospitalization or at discharge. We assessed hazards of post-discharge heart failure readmission and cardiovascular death at 1-year, and 30-, 60-, and 90-day from the date of discharge in the SGLT2is users and non-users. Cox proportional hazards models with propensity score-based inverse probability of treatment weighting were used to estimate hazard ratios and 95% confidence intervals. Results Among 56,343 patients with type 2 diabetes hospitalized for heart failure, 29,290 patients were included in the study cohort (mean [SD] age, 74.1 [10.8] years; 56.1% women); 818 patients (2.8%) were prescribed SGLT2is during index hospitalization or at discharge. Patients with a prescription for SGLT2i vs. those without prescription had lower rates of heart failure readmission or cardiovascular death at 1 year (22.4% vs. 25.3%; adjusted hazard ratio, 0.90 [95% confidence interval, 0.87–0.93]), and also at 30 days (7.0% vs. 7.7%%; 0.74 [0.69–0.79]). Conclusions Among patients with type 2 diabetes, initiating SGLT2i treatment after an episode of acute heart failure was significantly associated with a reduced combined risk of heart failure readmission and cardiovascular mortality in a nationwide cohort reflecting routine clinical practice.

Purpose This article was to collect data on the safety of coronavirus disease 2019 (COVID-19) vaccines in children with underlying medical conditions. Methods We constructed a prospective cohort of children and adolescents aged 5 to 19 years who had received at least one dose of COVID-19 vaccine. Patients diagnosed with and treated for chronic kidney disease, autoimmune disease, or other chronic conditions at the Seoul National University Children’s Hospital were recruited from June to December 2022. A mobile survey questionnaire was sent to their guardians. The presence of adverse events on the day (day 0), 3 weeks (day 21), and 6 months (day 180) after the 1st dose of COVID-19 vaccine was recorded by the guardians. Results A total of 73 children participated. The median age was 14 years, and 64.4% of the patients were male. On the day of immunization, 65.8% of the patients reported at least one adverse event. Pain at the injection site, fatigue, headache, arthralgia, and myalgia were the most common symptoms. The prevalence of adverse events decreased over time (65.8% on day 0, 27.4% between days 0 and 21, and 24.6% between days 21 and 180). Severe acute respiratory syndrome coronavirus 2 infection after the 1st dose occurred in 17 patients (23.3%) and one of the patients (5.88%) was hospitalized due to infection. Conclusions Adverse events after COVID-19 vaccination were generally mild in children and adolescents with underlying medical conditions. Our findings provide evidence for the safety of COVID-19 vaccination in the vulnerable pediatric population.

Summary: Background: Autoimmune hepatitis (AIH) varies significantly in incidence and prevalence across countries and regions. We aimed to examine global, regional, and national trends in incidence and prevalence of AIH from 1970 to 2022. Methods: We conducted a thorough search of the PubMed/MEDLINE, Embase, CINAHL, Google Scholar, and Cochrane databases from database inception to August 9, 2023, using the search term “autoimmune hepatitis” in combination with “incidence,” “prevalence,” or “trend.” Only general population-based observational studies with larger samples sizes were considered for inclusion. Studies that recruited convenience samples, and those with fewer than 50 participants were excluded. Summary data were extracted from published reports. A random effects model was used and pooled estimates with 95% CI were used to calculate the incidence and prevalence of AIH. Heterogeneity was evaluated using the I2 statistic. The study protocol was registered with PROSPERO, CRD42023430138. Findings: A total of 37 eligible studies, encompassing more than 239 million participants and 55,839 patients with AIH from 18 countries across five continents, were included in the analysis. Global pooled incidence and prevalence of AIH were found to be 1.28 cases per 100,000 inhabitant-years (95% CI, 1.01–1.63, I2 = 99·51%; number of studies, 33; sample population, 220,673,674) and 15.65 cases per 100,000 inhabitants (95% CI, 13.42–18.24, I2 = 99·75%; number of studies, 26; sample population, 217,178,684), respectively. The incidence of AIH was greater in countries with high Human Development Index (>0.92), in North America and Oceania (compared with Asia), among females, adults (compared with children), and high latitude (>45°). Similar patterns in AIH prevalence were observed. Pooled AIH prevalence increased gradually from 1970 to 2019 (1970–1999; 9.95 [4.77–15.13], I2 = 95·58% versus 2015–2022; 27.91 [24.86–30.96], I2 = 99·32%; cases per 100,000 inhabitants). The overall incidence and prevalence of AIH, as well as some subgroup analyses of the studies, displayed asymmetry in the funnel plots, suggesting potential evidence of publication bias. Interpretation: AIH incidence and prevalence have increased significantly and exhibit substantial variation across regions worldwide. Further research is required to assess the incidence and prevalence of AIH, specifically in South America and Africa. Funding: National Research Foundation of Korea.

Risk factors of MDR-TB remain unclear in South Korea, despite being an important public health issue. Findings from this study, which included ≥50,000 patients with TB from South Korea, suggests that immigrants and patients with lower income levels were strong predictors of MDR-TB in a high-income, high TB incidence country.

Abstract Background Fibrosing interstitial lung disease (F-ILD) is a major public health concern due to its poor prognosis. Recent clinical evidence shows that antifibrotic approaches such as pirfenidone and nintedanib provide better clinical outcome prediction in idiopathic pulmonary fibrosis (IPF) as well as selected progressive fibrosing ILD (PF-ILD) patients. Having epidemiologic insight into these diseases will be essential for the efficient utilization of these therapeutic resources. This study aimed to estimate the current prevalence, incidence, and mortality of F-ILD classified as idiopathic pulmonary fibrosis (IPF), PF-ILD other than IPF, and non-progressive F-ILD and their temporal trend in Korea. Methods Population-based retrospective cohort study was conducted using the Korean Health Insurance Review and Assessment (HIRA) database (2011–2018). Patients with IPF were identified using ICD-10 code, RID code, and differential diagnosis approach. By leveraging medical records available from claim data and referencing those used in clinical trials, rigorous diagnostic criteria for PF-ILD detection were implemented. Results For the past eight years, the prevalence of IPF and PF-ILD has progressively increased, while non-progressive F-ILD has remained stable. IPF, PF-ILD, and non-progressive F-ILD prevalence per 100,000 in 2018 were 16.9, 10.4, and 11.7, respectively. The incidence of IPF in 2018 was more than twice that of 2012. The incidence of PF-ILD in 2018 was 1.5 times higher than that in 2012. In 2018, the mortalites were 10.3% and 12.2% for IPF and PF-ILD, respectively. The mortality rate of PF-ILD was greater than that of IPF in all years. Unclassifiable PF-ILD and rheumatoid arthritis-PF-ILD had the highest proportion and mortality among the PF-ILD subtypes. Conclusion The prevalence and incidence of IPF and PF-ILD have been steadily increasing in recent years. The mortality rate of PF-ILD remained consistently high and exceeded those of IPF in all years.

Abstract Background Impaired respiratory function remains underrecognized in patients with type 2 diabetes (T2D), despite common pulmonary impairment. Meanwhile, there is little data available on the respiratory effects of sodium glucose cotransporter 2 inhibitors (SGLT2i). Hence, we examined the association between SGLT2i use and the risk of adverse respiratory events in a real-world setting. Methods We conducted a population-based, nationwide cohort study using an active-comparator new-user design and nationwide claims data of South Korea from January 2015 to December 2020. Among individuals aged 18 years or older, propensity score matching was done to match each new user of SGLT2is with dipeptidyl peptidase 4 inhibitors (DPP4is), with patients followed up according to an as-treated definition. The primary outcome was respiratory events, a composite endpoint of acute pulmonary edema, acute respiratory distress syndrome (ARDS), pneumonia, and respiratory failure. Secondary outcomes were the individual components of the primary outcome and in-hospital death. Cox models were used to estimate hazard ratios (HRs) and 95% CIs. Results Of 205,534 patient pairs in the propensity score matched cohort, the mean age of the entire cohort was 53.8 years and 59% were men, with a median follow-up of 0.66 years; all baseline covariates achieved balance between the two groups. Incidence rates for overall respiratory events were 4.54 and 7.54 per 1000 person-years among SGLT2i and DPP4i users, respectively, corresponding to a rate difference of 3 less events per 1000 person-years (95% CI − 3.44 to − 2.55). HRs (95% CIs) were 0.60 (0.55 to 0.64) for the composite respiratory endpoint, 0.35 (0.23 to 0.55) for acute pulmonary edema, 0.44 (0.18 to 1.05) for ARDS, 0.61 (0.56 to 0.66) for pneumonia, 0.49 (0.31 to 0.76) for respiratory failure, and 0.46 (0.41 to 0.51) for in-hospital death. Similar trends were found across individual SGLT2is, subgroup analyses of age, sex, history of comorbidities, and a range of sensitivity analyses. Conclusions These findings suggest a lower risk of adverse respiratory events associated with patients with T2D initiating SGLT2is versus DPP4is. This real-world evidence helps inform patients, clinicians, and guideline writers regarding the respiratory effects of SGLT2i in routine practice.

Background: Impact of immeasurable time bias (IMTB) is yet to be examined in self-controlled designs. Methods: We conducted case-crossover, case-time-control, and case-case-time-control analyses using Korea’s healthcare database. Two empirical examples among elderly patients were used: 1) benzodiazepines-hip fracture; 2) benzodiazepines-mortality. For cases, the date of hip fracture diagnosis or death was defined as the index date, and the inherited date of their matched cases for controls or future cases. Exposure was assessed in the 1–30 day (hazard) and 61–90 day (control) windows preceding the index date. A non-missing exposure setting included in- and outpatient prescriptions and the pseudo-outpatient setting included only the outpatients. Conditional logistic regression was done to estimate odds ratios (ORs) with 95% confidence intervals (CIs), where the relative difference in OR among the two settings was calculated to quantify the IMTB. Results: The IMTB had negligible impacts in the hip fracture example in the case-crossover (non-missing exposure setting OR 1.27; 95% CI, 1.12–1.44; pseudo-outpatient setting OR 1.21; 95% CI, 1.06–1.39; magnitude 0.05), case-time-control (OR 1.18; 95% CI, 0.98–1.44; OR 1.13; 95% CI, 0.92–1.38; 0.04, respectively), and case-case-time-control analyses (OR 0.99; 95% CI, 0.80–1.23; OR 0.94; 95% CI, 0.75–1.18; 0.05, respectively). In the mortality example, IMTB had significant impacts in the case-crossover (non-missing exposure setting OR 1.44; 95% CI, 1.36–1.52; pseudo-outpatient setting OR 0.72; 95% CI, 0.67–0.78; magnitude 1.00), case-time-control (OR 1.38; 95% CI, 1.26–1.51; OR 0.68; 95% CI, 0.61–0.76; 1.03, respectively), and case-case-time-control analyses (OR 1.27; 95% CI, 1.15–1.40; OR 0.62; 95% CI, 0.55–0.69; 1.05, respectively). Conclusion: Although IMTB had negligible impacts on the drug’s effect on acute events, as these are unlikely to be accompanied with hospitalizations, it negatively biased the drug’s effect on mortality, an outcome with prodromal phases, in the three self-controlled designs.

Abstract Introduction To better understand the conditions associated with pertussis diagnosis among older adults in South Korea, a matched case–control study was conducted of individuals ≥ 50 years diagnosed with pertussis between 2009 and 2018. Methods Pertussis cases were identified using the nationwide Health Insurance Review and Assessment service (HIRA) database. Each case was then matched to up to 10 controls identified using the National Health Insurance Service–National Sample Cohort (NHIS-NSC) by age, sex, and geographic region at index date. In the 12 months and 30 days prior to index date, the presence of clinical characteristics previously reported to be related to pertussis and pertussis-like conditions were assessed, respectively. A conditional multivariate logistic regression model was then used to calculate odds ratios (ORs) of pertussis diagnosis, adjusted for each of the characteristics. Results Pertussis cases (n = 1004) generally demonstrated a higher prevalence of comorbidities compared to controls (n = 9710). Pre-existing asthma and chronic obstructive pulmonary disease (COPD) within 12 months of index date were associated with a two-fold increased risk of pertussis with adjusted ORs (95% confidence interval) of 2.08 (1.68–2.58) and 2.32 (1.59–3.39), respectively. Gastroesophageal reflux disease [GERD; 2.67 (2.23–3.19)], cancer [1.68 (1.23–2.31)], cardiovascular disease [1.62 (1.31–2.00)], renal disease [1.56 (1.12–2.16)], autoimmune disease [1.50 (1.25–1.79)], and hyperlipidemia [1.43 (1.16–1.77)] were also associated with pertussis diagnosis. Finally, acute respiratory events within 30 days prior to index date, such as pneumonia, acute bronchitis, and upper respiratory tract infection (URTI), were highly associated with increased odds of pertussis diagnosis [adjusted ORs of 8.28 (5.10–13.44), 4.86 (3.84–6.14), and 2.90 (2.30–3.67), respectively]. Conclusions This study’s findings complement and expand upon previous studies on the adult pertussis population, generating real-world data to describe underlying clinical characteristics of those diagnosed with pertussis in South Korea.

Abstract N-Nitrosodimethylamine (NDMA) detected above the acceptable level in ranitidine products has been a great global concern. To examine the risk of cancer among people treated with ranitidine, we conducted a cohort study using the National Health Insurance Service-National Sample Cohort data (2002–2015) of South Korea. Patients were aged 40 or above as of January 2004 and began receiving ranitidine or other histamine-2 receptor antagonist (H2RA), active comparator, without a history of H2RAs prescription during the prior 2-years. The lag time was designated up to 6 years. The outcomes were an overall incident cancer risk and the risk of major single cancers during the follow-up. The association between ranitidine use and cancer risk was examined by Cox regression model. After exclusion and propensity score matching, 25,360 patients were available for analysis. The use of ranitidine was not associated with the overall cancer risk and major individual cancers [overall cancer: incidence rate per 1000 person-years, 2.9 vs 3.0 among the ranitidine users and other H2RAs users, respectively; adjusted hazard ratio (HR) and 95% confidence interval (95% CI) for all cancers, 0.98 (0.81–1.20)]. The higher cumulative exposure to ranitidine did not increase the cancer risk. Given the insufficient follow-up period, these findings should be interpreted carefully.

Abstract Upon withdrawal of propacetamol, an injectable formulation of the paracetamol prodrug, in Europe due to safety concerns, South Korea’s regulatory body requested a post-marketing surveillance study exploring its safety profile. We characterized regional disparities in adverse events (AE) associated with propacetamol between Asia and Europe using the World Health Organization’s pharmacovigilance database, VigiBase. We performed disproportionality analyses using reporting odds ratios (rOR) and information component (IC) to determine whether five AEs (anaphylaxis, Stevens–Johnson syndrome, thrombosis, contact dermatitis/eczema, injection site reaction [ISR]) were associated with propacetamol versus non-propacetamol injectable antipyretics in Asia and Europe, separately. In Asia, there was a high reporting ratio of propacetamol-related ISR (rOR 5.72, 95% CI 5.19–6.31; IC025 1.27), satisfying the signal criteria; there were no reports of thrombosis and contact dermatitis/eczema. Two signals were identified in Europe, with higher reporting ratios for thrombosis (rOR 7.45, 95% CI 5.19–10.71; IC025 1.92) and contact dermatitis/eczema (rOR 16.73, 95% CI 12.48–22.42; IC025 2.85). Reporting ratios of propacetamol-related anaphylaxis were low for Asia and Europe. While signals were found for thrombosis and contact dermatitis/eczema in Europe, these were not detected in Asia. These findings suggest potential ethnic differences in propacetamol-related AEs between Asia and Europe, which could serve as supportive data for future decision-making.

Abstract Safety profiles of the influenza vaccine and its subtypes are still limited. We aimed to address this knowledge gap using multiple data mining methods and calculated performance measurements to evaluate the precision of different detection methods. We conducted a post-marketing surveillance study between 2005 and 2019 using the Korea Adverse Event Reporting System database. Three data mining methods were applied: (a) proportional reporting ratio, (b) information component, and (c) tree-based scan statistics. We evaluated the performance of each method in comparison with the known adverse events (AEs) described in the labeling information. Compared to other vaccines, we identified 36 safety signals for the influenza vaccine, and 7 safety signals were unlabeled. In subtype-stratified analyses, application site disorders were reported more frequently with quadrivalent and cell-based vaccines, while a wide range of AEs were noted for trivalent and egg-based vaccines. Tree-based scan statistics showed well-balanced performance. Among the detected signals of influenza vaccines, narcolepsy requires special attention. A wider range of AEs were detected as signals for trivalent and egg-based vaccines. Although tree-based scan statistics showed balanced performance, complementary use of other techniques would be beneficial when large noise due to false positives is expected.

Background/Purpose(s): The World Health Organization (WHO) released treatment guidelines for multidrug resistant tuberculosis (MDR-TB) in 2008, with subsequent revisions in 2011; Korea disseminated corresponding guidelines in 2011 and 2014, respectively. Thus, we aimed to investigate the temporal trends of and the updated guideline's impact on the prescription patterns of anti-TB drugs. Methods: We conducted a time-series study using Korea's nationwide healthcare database (2007–2015), where patients with TB or MDR-TB were included. Only anti-TB drugs prescribed during the intensive phase of treatment for TB (two months) or MDR-TB (eight months) were assessed. We estimated the annual utilization of TB treatment regimens and the relative difference (RD) in the proportion of MDR-TB treatment medications between the following periods: before the first Korean guideline (June 2008 to March 2011); between the first and revised guidelines (April 2011 to July 2014); after the revised guideline (August 2014 to December 2015). Results: Of 3523 TB (mean age 54.1 years; male 56.8%) patients, treatment regimens for TB complied with guideline recommendations as >80% of patients received either quadruple (mean 66.8%) or triple (14.5%) therapy of first-line anti-TB drugs. Following the WHO's guideline update, prescription patterns changed accordingly among 111 MDR-TB (mean age 46.0 years; male 67.6%) patients, as use of pyrazinamide (RD +20.3%) and prothionamide (+11.5%) increased (recommended to be compulsory), and streptomycin (−43.1%) decreased (ototoxicity risks). Conclusions: Anti-TB drug prescription patterns for both TB and MDR-TB well reflected WHO's treatment guideline as well as corresponding domestic guidelines of South Korea.

Abstract There has been a growing attention on using machine learning (ML) in pharmacovigilance. This study aimed to investigate the utility of supervised ML algorithms on timely detection of safety signals in the Korea Adverse Event Reporting System (KAERS), using infliximab as a case drug, between 2009 and 2018. Input data set for ML training was constructed based on the drug label information and spontaneous reports in the KAERS. Gold standard dataset containing known AEs was randomly divided into the training and test sets. Two supervised ML algorithms (gradient boosting machine [GBM], random forest [RF]) were fitted with hyperparameters tuned on the training set by using a fivefold validation. Then, we stratified the KAERS data by calendar year to create 10 cumulative yearly datasets, in which ML algorithms were applied to detect five pre-specified AEs of infliximab identified during post-marketing surveillance. Four AEs were detected by both GBM and RF in the first year they appeared in the KAERS and earlier than they were updated in the drug label of infliximab. We further applied our models to data retrieved from the US Food and Drug Administration Adverse Event Reporting System repository and found that they outperformed existing disproportionality methods. Both GBM and RF demonstrated reliable performance in detecting early safety signals and showed promise for applying such approaches to pharmacovigilance.

Abstract The phenotypes of atopic dermatitis (AD) are diverse, and ethnic differences have been suggested. To date, few studies have explored large-scale national data on the treatment patterns of AD in Asians. Therefore, we aimed to examine real-world treatment patterns for AD, including the probability of discontinuation of AD treatment and restart after discontinuation. A retrospective observational study was conducted using the nationwide healthcare database in South Korea between January 1, 2016 to July 31, 2020. We identified 944,559 pediatric patients and 1,066,453 adults with AD. Topical corticosteroids and antihistamines were the most commonly prescribed medications in all age groups. The frequency of topical corticosteroid prescription decreased as the age increased. Although immunosuppressive drugs were not widely used in both children and adults, cyclosporine was the most frequently prescribed immunosuppressant, particularly among those aged 12 years or more (1–2%). Pediatric patients were more likely to discontinue treatment than adult patients. Treatment restart for moderate-to-severe AD was earlier than that for overall AD. In conclusion, significant differences were observed in the treatment patterns of AD between pediatric and adult patients. These findings will improve our understanding of the latest treatment patterns for AD, which may contribute to decision-making in clinical practice.

OBJECTIVES This study investigated the reporting rates of adverse events following immunization (AEFIs) to the spontaneous reporting system (SRS) and its predictors among individuals with AEFIs after coronavirus disease 2019 (COVID-19) vaccination. METHODS A cross-sectional, web-based survey was conducted from December 2, 2021 to December 20, 2021, recruiting participants >14 days after completion of a primary COVID-19 vaccination series. Reporting rates were calculated by dividing the number of participants who reported AEFIs to the SRS by the total number of participants who experienced AEFIs. We estimated adjusted odds ratios (aORs) using multivariate logistic regression to determine factors associated with spontaneous AEFIs reporting. RESULTS Among 2,993 participants, 90.9% and 88.7% experienced AEFIs after the first and second vaccine doses, respectively (reporting rates, 11.6 and 12.7%). Furthermore, 3.3% and 4.2% suffered moderate to severe AEFIs, respectively (reporting rates, 50.5 and 50.0%). Spontaneous reporting was more prevalent in female (aOR, 1.54; 95% confidence interval [CI], 1.31 to 1.81); those with moderate to severe AEFIs (aOR, 5.47; 95% CI, 4.45 to 6.73), comorbidities (aOR, 1.31; 95% CI, 1.09 to 1.57), a history of severe allergic reactions (aOR, 2.02; 95% CI, 1.47 to 2.77); and those who had received mRNA-1273 (aOR, 1.25; 95% CI, 1.05 to 1.49) or ChAdOx1 (aOR, 1.62; 95% CI, 1.15 to 2.30) vaccines versus BNT162b2. Reporting was less likely in older individuals (aOR, 0.98; 95% CI, 0.98 to 0.99 per 1-year age increment). CONCLUSIONS Spontaneous reporting of AEFIs after COVID-19 vaccination was associated with younger age, female sex, moderate to severe AEFIs, comorbidities, history of allergic reactions, and vaccine type. AEFIs under-reporting should be considered when delivering information to the community and in public health decision-making.

Abstract Aims/Introduction To evaluate the relationship between early insulin initiation within a year after type 2 diabetes mellitus diagnosis and the risk of diabetic complications. Materials and methods We carried out a cohort study using the Korean National Health Insurance Service database. The study participants were newly diagnosed with type 2 diabetes mellitus between 2009 and 2013. After applying propensity score matching (1:1) to the cohort of patients who received two or more oral antidiabetic drugs (OADs) or insulin as the first prescription within 1 year after type 2 diabetes mellitus diagnosis, we computed hazard ratios (HRs) and 95% confidence intervals (CIs) using a Cox proportional hazards regression to compare the risk of diabetes‐related microvascular and macrovascular complications and all‐cause mortality in insulin versus OAD initiators. Results Within the cohort, 52,188 and 1,804 patients received OAD and insulin, respectively. After matching, each group contained 534 patients. Compared with the OAD group, the risk of overall microvascular complications was significantly higher for insulin (HR 1.48, 95% CI 1.28–1.71). No increased risks of overall macrovascular complications (HR 0.90, 95% CI 0.62–1.30) and all‐cause mortality were observed (HR 1.06, 95% CI 0.67–1.68). Conclusions In the present study, early insulin treatment was not associated with the risk of macrovascular complications and all‐cause mortality compared with OAD treatment; however, the risk of microvascular complications was higher in the insulin group.

Background 2018 American Heart Association/American College of Cardiology cholesterol guideline recommends statin in patients with chronic and/or stable liver disease for secondary prevention of atherosclerotic cardiovascular disease yet remains equivocal on the adequate intensity of statin for patients with chronic liver disease (CLD). We aimed to assess the association between statin intensity and mortality among patients with CLD with atherosclerotic cardiovascular disease. Methods and Results We conducted a population‐based cohort study in South Korea. We assessed the risk of survival and clinical outcomes using inverse probability of treatment‐weighted Cox proportional hazards regression. We also estimated the absolute risk difference between treatment groups based on the Poisson distribution. During an average of 2.35 person‐years, 10 442 patients with CLD with atherosclerotic cardiovascular disease were identified. Among those patients, 5515 (52.8%) received high‐intensity statin, and 4927 (47.2%) received low/moderate‐intensity statin. High‐intensity statin was associated with lower risk for all‐cause mortality (hazard ratio [HR], 0.83 [95% CI, 0.75–0.92]), cardiovascular‐cause mortality (HR, 0.85 [0.71–1.01]), liver‐cause mortality (HR, 0.72 [0.54–0.97]) compared with low/moderate‐intensity statin. Although both hospitalizations for recurrent myocardial infarction and stroke were shown to be increased among high‐intensity statin users, effect estimate was homogeneous in the absolute scale (myocardial infarction: HR, 1.12 [1.04–1.19], risk difference, 7.57 [−0.69 to 15.84] per 1000 person‐years; stroke: HR, 1.11 [0.97 to 1.27]; risk difference, −1.70 [−5.19 to 1.78]). Conclusions Among patients with CLD with atherosclerotic cardiovascular disease, high‐intensity statin was significantly associated with a lower risk of mortality. These findings herein support the guidelines for statin use in patients with CLD while demonstrating potential benefit of optimal intensity use.

BackgroundExisting data on the use of nonsteroidal anti-inflammatory drugs (NSAIDs) during late pregnancy is well established, providing assurance. However, the use of NSAIDs during early pregnancy remains inconclusive owing to conflicting findings on adverse neonatal outcomes as well as the limited data on adverse maternal outcomes. Therefore, we sought to investigate whether early prenatal exposure to NSAIDs was associated with neonatal and maternal adverse outcomes.Methods and findingsWe conducted a nationwide, population-based cohort study using Korea's National Health Insurance Service (NHIS) database with a mother-offspring cohort constructed and validated by the NHIS to include all live births in women aged 18 to 44 years between 2010 and 2018. We defined exposure to NSAIDs as at least two records of NSAID prescriptions during early pregnancy (first 90 days of pregnancy for congenital malformations and first 19 weeks for nonmalformation outcomes) and compared against three distinct referent groups of (1) unexposed, no NSAID prescription during the 3 months before pregnancy start to end of early pregnancy; (2) acetaminophen-exposed, at least two acetaminophen prescriptions during early pregnancy (i.e., active comparator); and (3) past users, at least two NSAID prescriptions before the start of pregnancy but no relevant prescriptions during pregnancy. Outcomes of interest were adverse birth outcomes of major congenital malformations and low birth weight and adverse maternal outcomes of antepartum hemorrhage and oligohydramnios. We estimated relative risks (RRs) with 95% CIs using generalized linear models within a propensity score (PS) fine stratification weighted cohort that accounted for various potential confounders of maternal sociodemographic characteristics, comorbidities, co-medication use, and general markers of burden of illness. Of 1.8 million pregnancies in the PS weighted analyses, exposure to NSAIDs during early pregnancy was associated with slightly increased risks for neonatal outcomes of major congenital malformations (PS-adjusted RR, 1.14 [CI, 1.10 to 1.18]) and low birth weight (1.29 [1.25 to 1.33]), and for maternal outcome of oligohydramnios (1.09 [1.01 to 1.19]) but not antepartum hemorrhage (1.05 [0.99 to 1.12]). The risks of overall congenital malformations, low birth weight, and oligohydramnios remained significantly elevated despite comparing NSAIDs against acetaminophen or past users. Risks of adverse neonatal and maternal outcomes were higher with cyclooxygenase-2 selective inhibitors or use of NSAIDs for more than 10 days, whereas generally similar effects were observed across the three most frequently used individual NSAIDs. Point estimates were largely consistent across all sensitivity analyses, including the sibling-matched analysis. Main limitations of this study are residual confounding by indication and from unmeasured factors.ConclusionsThis large-scale, nationwide cohort study found that exposure to NSAIDs during early pregnancy was associated with slightly higher risks of neonatal and maternal adverse outcomes. Clinicians should therefore carefully weigh the benefits of prescribing NSAIDs in early pregnancy against its modest, but possible, risk of neonatal and maternal outcomes, where if possible, consider prescribing nonselective NSAIDs for

Abstract Few studies assessed the association between major adverse cardiovascular events and adherence to warfarin and direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF). Therefore, we aimed to evaluate the effects of adherence to oral anticoagulants (OACs) in patients with AF using claims data (July 2014–April 2019). Using the initial 3-month medication possession rate (MPR), patients were categorized into adherent (MPR ≥ 0.8) or non-adherent (MPR

Background In South Korea, women aged 66 years are eligible for complimentary bone mineral density (BMD) screening via the National Screening Program for Transitional Ages. We aimed to evaluate the 10-year fracture risk in women receiving BMD screening between January 2008 and December 2015. Methods BMD was classified as normal (T-score ≥−1.0 standard deviation [SD]), osteopenia (T-score −2.5 SD), and osteoporosis (T score ≤−2.5 SD) from dual-energy X-ray absorptiometry. Follow-up continued from the screening date until a diagnosis for clinical fragility fracture (including sites of the vertebrae, hip, pelvis, clavicle, humerus, forearm, wrist, lower leg, and ankle), censored at the earliest date of trauma, death, or December 2017; fracture was ascertained using diagnostic codes from the National Health Insurance Service database. A multivariable Cox proportional hazard model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk of fracture in women with osteopenia or osteoporosis relative to women with normal BMD. Results Among the 271,197 women screened, 44.0% had osteopenia and 35.2% had osteoporosis. The 10 year cumulative incidence of fragility fractures was 31.1%, 37.5%, and 44.3% in women with normal BMD, osteopenia, and osteoporosis, respectively. Fracture risk was higher in women with osteopenia (HR, 1.31; 95% CI, 1.28 to 1.34) and osteoporosis (HR, 1.68; 95% CI, 1.64 to 1.72) than in women with normal BMD. Conclusion Women with osteopenia and women with osteoporosis, identified by the national BMD screening program, demonstrated a substantially elevated risk of fracture.

Background/Aims: Although anti-tumor necrosis factor (TNF) agents have been widely used to treat ulcerative colitis (UC), the real-world incidence of suboptimal response to anti-TNF agents has not been thoroughly investigated, especially among Asians. Methods: Using the Korean National Health Insurance database, we collected data on UC patients who initiated anti-TNF agents between July 1, 2014, and June 30, 2017. We assessed suboptimal responses, including anti-TNF discontinuation or dose escalation, switching to other biologics, augmentation with a non-biologic therapy, and the requirement for colectomy. Results: A total of 1,268 patients were included as new anti-TNF users (infliximab 713, adalimumab 433, golimumab 122). The proportion of patients who experienced at least one suboptimal response within 1 year among all patients was 63.5%, including 59.1%, 69.5%, and 68.0% of patients treated with infliximab, adalimumab, and golimumab, respectively. The cumulative incidences of at least one suboptimal response over time were 41.5%, 63.7%, 80.5%, and 87.1% at 6, 12, 24, and 36 months, respectively. Cox proportional hazards modeling revealed that adalimumab was associated with a higher risk of at least one suboptimal response (hazard ratio [HR], 1.29; 95% confidence interval [CI], 1.13 to 1.48), dose escalation (HR, 4.35; 95% CI, 2.97 to 6.38) and discontinuation (HR, 1.25; 95% CI, 1.03 to 1.52) than infliximab. Golimumab was associated with a higher risk of switching to other biologics than infliximab (HR, 1.78; 95% CI, 1.21 to 2.60). Conclusions: More than half of Korean UC patients had suboptimal responses to anti-TNF agents within 1 year. UC patients treated with infliximab might be less prone to suboptimal responses than those treated with adalimumab or golimumab.

Anticoagulants are a potential treatment for the thrombotic complications resulting from COVID-19. We aimed to determine the association between anticoagulant use and adverse outcomes among hospitalized patients with COVID-19. We used data from the COVID-19 International Collaborative Research Project in South Korea from January to June 2020. We defined exposure using an intention-to-treat approach, with person-time classified as use or non-use of anticoagulants at cohort entry, and a time-varying approach. The primary outcome was all-cause, in-hospital mortality; the secondary outcome was a composite including respiratory outcomes, cardiovascular outcomes, venous thromboembolism, major bleeding, and intensive care unit admission. Cox proportional hazards models estimated adjusted hazard ratios (HRs) of the outcomes comparing use versus non-use of anticoagulants. Our cohort included 2,677 hospitalized COVID-19 patients, of whom 24 received anticoagulants at cohort entry. Users were older and had more comorbidities. The crude incidence rate (per 1,000 person-days) of mortality was 5.83 (95% CI: 2.80, 10.72) among anticoagulant users and 1.36 (95% CI: 1.14, 1.59) for non-users. Crude rates of the composite outcome were 3.20 (95% CI: 1.04, 7.47) and 1.80 (95% CI: 1.54, 2.08), respectively. Adjusted HRs for mortality (HR: 1.12, 95% CI: 0.48, 2.64) and the composite outcome (HR: 0.79, 95% CI: 0.28, 2.18) were inconclusive. Although our study was not able to draw conclusions on anticoagulant effectiveness for COVID-19 outcomes, these results can contribute to future knowledge syntheses of this important question. Our study demonstrated that the dynamic pandemic environment may have important implications for observational studies of COVID-19 treatment effectiveness.

Abstract The spatial interpolation of precipitation has been employed in a number of fields, including by spatially downscaling the Global Circulation Model (GCM) to a finer scale. Most precipitation events become more sporadic when the coverage area increases (i.e., a portion of the points experience zero precipitation). However, spatial interpolations of precipitation generally ignore these dry areas, and the interpolated grids are filled with certain precipitation amounts. Subsequently, no delineation of dry and wet regions can be made. Therefore, the current study suggested a novel approach to determine dry areas in spatial interpolations of precipitation events by assigning latent negative precipitation (LNP) to points with observed precipitation values of zero. The LNP-assigned points are then employed in a spatial interpolation. After that, the dry region can be determined using the negative region (i.e., points with zero precipitation). The magnitude of LNP can be defined by multiplying the precipitation values of neighboring stations by a tuning parameter. The LNP method and the tuning parameter are tested on weather stations covering South Korea. The results indicate that the proposed LNP method can be suitable for the spatial interpolation of precipitation events by delineating dry and wet regions. Additionally, the tuning parameter plays a special role in that it increases in value with longer precipitation durations and denser networks. A value of 0.5–1.5 can be suggested for the tuning parameter as a rule of thumb when high accuracy for final products of interpolated precipitation is not critical. For future studies, the LNP model derived herein can be tested over much larger areas, such as the United States, and the model can also be easily adopted for other variables with spatially sporadic values.

Summary: Background: Monoclonal antibody (mAb) and Fc-fusion protein (FcP) are highly effective therapeutic biologics. We aimed to analyse consumption and expenditure trends in 14 Asia-Pacific countries/regions (APAC) and three benchmark countries (the UK, Canada, and the US). Methods: We analysed 440 mAb and FcP biological products using the IQVIA-MIDAS global sales database. For each year between 2010 and 2020 inclusive, we used standard units (SU) sold per 1000 population and manufacture level price (standardised in 2019 US dollars) to evaluate consumption (accessibility) and expenditure (affordability). Changes of consumption and expenditure were estimated using compound annual growth rate (CAGR). Correlations between consumption, country's economic and health performance indicators were measured using Spearman correlation coefficient. Findings: Between 2010 and 2020, CAGRs of consumption in each region ranged from 7% to 34% and the CAGRs of expenditure ranged from 9% to 31%. The median consumption of biologics was extremely low in lower-middle-income economies (0·29 SU/1000 population) compared with upper-middle-income economies (1·20), high-income economies (40·94) and benchmark countries (109·55), although the median CAGRs of biologics consumption in lower-middle-income economies (31%) was greater than upper-middle-income (14%), high-income economies (13%) and benchmark countries (9%). Consumption was correlated with GDP per capita [Spearman's rank correlation coefficient (r) = 0·75, p < 0·001], health expenditure as a percentage of total (r = 0·83, p < 0·001) and medical doctors’ density (r = 0·85, p < 0·001). Interpretation: There have been significant increases in mAb and FcP biologics consumption and expenditure, however accessibility of biological medicines remains unequal and is largely correlated with country's income level. Funding: This research was funded by NHMRC Project Grant GNT1157506 and GNT1196900; Enhanced Start-up Fund for new academic staff and Internal Research Fund, Department of Medicine, LKS Faculty of Medicine, University of Hong Kong.

Extreme rainfall and floods have increased in frequency and severity in recent years, due to climate change and urbanization. Consequently, interest in estimating the probable maximum precipitation (PMP) has been burgeoning. The World Meteorological Organization (WMO) recommends two types of methods for calculating the PMP: hydrometeorological and statistical methods. This study proposes a modified Hershfield’s nomograph method and assesses the changes in PMP values based on the two representative concentration pathway (RCP4.5 and RCP8.5) scenarios in South Korea. To achieve the intended objective, five techniques were employed to compute statistical PMPs (SPMPs). Moreover, the most suitable statistical method was selected by comparing the calculated SPMP with the hydrometeorological PMP (HPMP), by applying statistical criteria. Accordingly, SPMPs from the five methods were compared with the HPMPs for the historical period of 2020 and the future period of 2100 for RCP 4.5 and 8.5 scenarios, respectively. The results confirmed that the SPMPs from the modified Hershfield’s nomograph showed the smallest MAE (mean absolute error), MAPE (mean absolute percentage error), and RMSE (root mean square error), which are the best results compared with the HPMP with an average SPMP/HPMP ratio of 0.988 for the 2020 historical period. In addition, Hershfield’s method with varying KM exhibits the worst results for both RCP scenarios, with SPMP/HPMP ratios of 0.377 for RCP4.5 and 0.304 for RCP8.5, respectively. On the contrary, the modified Hershfield’s nomograph was the most appropriate method for estimating the future SPMPs: the average ratios were 0.878 and 0.726 for the 2100 future period under the RCP 4.5 and 8.5 scenarios, respectively, in South Korea.

OBJECTIVES This study explored predictors of coronavirus disease 2019 (COVID-19) booster hesitancy among fully vaccinated young adults and parental COVID-19 vaccine hesitancy for their children. METHODS This cross-sectional study administered an online survey from December 2 to December 20, 2021. We enrolled participants aged 18-49 years, for whom ≥2 weeks had passed after their initial COVID-19 vaccination. We estimated odds ratios (ORs) with 95% confidence intervals (CIs) using multivariate logistic regression to evaluate factors associated with booster/vaccine hesitancy. RESULTS Among the 2,993 participants, 48.8% showed hesitancy (wait and see: 40.2%; definitely not: 8.7%). Booster hesitancy was more common among women (OR, 1.25; 95% CI, 1.05 to 1.50), younger people (OR, 1.44; 95% CI, 1.17 to 1.77), those with a lower education level (OR, 2.05; 95% CI, 1.10 to 3.82), those who received the mRNA-1273 vaccine type (OR, 2.01; 95% CI, 1.65 to 2.45), and those who experienced serious adverse events following previous COVID-19 vaccination (OR, 2.03; 95% CI, 1.47 to 2.80). The main reasons for booster hesitancy were concerns about safety (54.1%) and doubts about efficacy (29.8%). Among the 1,020 respondents with children aged

Purpose: Inhaled Corticosteroids (ICSs) and oral Leukotriene Receptor Antagonists (LTRAs) are commonly prescribed asthma preventers, however, concerns have been raised as to whether montelukast (LTRA) is associated with an increase in occurrences of neuropsychiatric side effects in children. Our study was conducted to observe prescribing patterns of asthma preventers among paediatric patients specifically focusing on ICSs and LTRAs between Australia and South Korea to see intercountry differences in the use of these medicines.Materials and Methods: The Health Insurance Review and Assessment Paediatric Patients Sample dataset for South Korea and data provided by Services Australia were used in the study. Paediatric patients aged between 3 and 19 with more than one dispensing of an asthma preventer and at least one reliever between 1 Jan 2018 and 31 December 2018 were selected. Prevalence per 1,00,000 persons and standardised prevalence were estimated.Results: A total of 3,58,470 patients (2,04,270 from South Korea and 1,54,200 from Australia) were included in the study. A higher prevalence of ICS-based inhalers was seen in Australia with 80.1% compared to 13.5% in South Korea. In addition, Australia showed a stronger tendency of prescribing high dose ICS-based inhalers compared to South Korea with 22.9% vs. 4.9%. In contrast, use of LTRAs was more prevalent in South Korea with 57.6% while in Australia, montelukast was the only LTRA dispensed at a proportion of 18.9%. Moreover, 29.9% of xanthines which are orally available preventers, were prescribed more frequently in South Korea compared to Australia (0.1%).Conclusion: Australia showed a tendency of prescribing ICS-based preventers whereas South Korea exhibited a preference towards the oral LTRAs. Given the potential risk of neuropsychiatric side effects among paediatric patients with montelukast, reasons for the high use of montelukast in South Korea should be investigated further.

Abstract The prevalence of diabetes during pregnancy and the need for the treatment are increasing. We aimed to investigate antidiabetic medications (ADM) use among pregnant women and their characteristics. Using Korea’s nationwide healthcare database, we included women aged 15–49 years with births during 2004–2013. The prevalence and secular trend of ADM use were assessed in 3 periods: pre-conception period, first trimester, and second/third trimesters. To compare maternal characteristics between pregnancies with and without ADM prescription, we used the χ2 or Fisher’s exact test and Cochran-Armitage trend test. The prescription patterns analyzed by calendar year, age, insurance type, income, area, and medical institution. Of 81,559 pregnancies, 222 (0.27%) and 305 (0.37%) were exposed ADM during pre-conception and pregnancy periods, respectively. ADM prescriptions increased significantly by an 11.3-fold in second/third trimesters, while a 2.9-fold in first trimester. ADM use is more prevalent in women aged older and living in urban areas. Metformin was most used in the pre-conception period, while insulins were most during pregnancy. About 0.4% of women received ADM during pregnancy; a rate was lower than that in western countries. Non-recommended medications were more common in first trimester, which warrants pregnancy screening for women taking ADM.

Abstract Background With antidepressants (ADs) having minimal therapeutic effects during the initial weeks of treatment, benzodiazepines (BZDs) are concomitantly used to alleviate depressive symptoms of insomnia or anxiety. However, with mortality risks associated with this concomitant use yet to be examined, it remains unclear as to whether this concomitant therapy offers any benefits in treating depression. Methods We conducted a population-based cohort study using South Korea’s nationwide healthcare database from 2002 to 2017. Of 2.6 million patients with depression, we identified 612,729 patients with incident depression and newly prescribed ADs or BZDs, by excluding those with a record of diagnosis or prescription within the 2 years prior to their incident diagnosis. We classified our study cohort into two discrete groups depending on the type of AD treatment received within 6 months of incident diagnosis—AD monotherapy and AD plus BZD (AD+BZD) therapy. We matched our study cohort in a 1:1 ratio using propensity scores to balance baseline characteristics and obtain comparability among groups. The primary outcome was all-cause mortality, and patients were followed until the earliest of outcome occurrence or end of the study period. We conducted multivariable Cox proportional hazards regression analysis to estimate adjusted hazards ratios (HRs) with 95% confidence intervals (CIs) for the risk of mortality associated with AD+BZD therapy versus AD monotherapy. Results The propensity score-matched cohort had 519,780 patients with 259,890 patients in each group, where all baseline characteristics were well-balanced between the two groups. Compared to AD monotherapy, AD+BZD therapy was associated with an increased risk of all-cause mortality (adjusted HR, 1.04; 95% CI, 1.02 to 1.06). Conclusions Concomitantly initiating BZDs with ADs was associated with a moderately increased risk of mortality. Clinicians should therefore exercise caution when deciding to co-prescribe BZDs with ADs in treating depression, as associated risks were observed.