Concordant and discordant breast density patterns by different approaches for assessing breast density and breast cancer risk.

Purpose: To examine the discrepancy in breast density assessments by radiologists, LIBRA software, and AI algorithm and their association with breast cancer risk.

Methods: Among 74,610 Korean women aged ≥ 34 years, who underwent screening mammography, density estimates obtained from both LIBRA and the AI algorithm were compared to radiologists using BI-RADS density categories (A-D, designating C and D as dense breasts). The breast cancer risks were compared according to concordant or discordant dense breasts identified by radiologists, LIBRA, and AI.

Association between exposure to antibiotics during pregnancy or early infancy and risk of autism spectrum disorder, intellectual disorder, language disorder, and epilepsy in children: population based cohort study.

Objective: To evaluate the association between antibiotic use during pregnancy or early infancy and the risk of neurodevelopmental disorders in children.

Design: Nationwide population based cohort study and sibling analysis.

Setting: Korea's National Health Insurance Service mother-child linked database, 2008-21.

Cardiovascular safety of evogliptin dual and triple therapy in patients with type 2 diabetes: a nationwide cohort study.

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.

Predictors, mortality, and health outcomes of intensive phase non-adherence to a regimen in patients with drug-susceptible tuberculosis: a nationwide linkage database.

Objectives: The clinical importance of adhering to the regimen in tuberculosis patients has been widely investigated, but most studies were conducted in controlled settings and in limited populations. We aimed to measure the level of real-world adherence during intensive phase and investigate the predictors and the risk of mortality and health outcomes of intensive phase non-adherence in tuberculosis patients.

Study Design: We conducted a nationwide cohort study by linking the Korean National Tuberculosis Surveillance System and the National Health Information Database.

Evaluation of the Regulatory Required Post-Authorization Safety Study for Propacetamol: Nested Case-Control and Case-Time-Control Studies.

Purpose: Following the withdrawal of propacetamol in Europe owing to safety issues, the regulatory authority of South Korea requested a post-marketing surveillance study to investigate its safety profile.

Materials And Methods: We conducted nested case-control and case-time-control (CTC) analyses of cases and controls identified for outcomes of interest, including anaphylaxis, thrombosis, and Stevens-Johnson syndrome (SJS), using the claims database of South Korea, 2010-2019. Risk-set sampling was used to match each case with up to 10 controls for age, sex, cohort entry date, and follow-up duration.

Outcomes of SGLT-2i and GLP-1RA Therapy Among Patients With Type 2 Diabetes and Varying NAFLD Status.

Importance: Nonalcoholic fatty liver disease (NAFLD) is a cardiovascular risk factor, but whether sodium-glucose cotransporter-2 inhibitors (SGLT-2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) are associated with reduced cardiovascular risk in patients with type 2 diabetes (T2D) and concomitant NAFLD remains uncertain.

Objective: To investigate the outcomes of SGLT-2i and GLP-1RA therapy among patients with T2D varied by the presence or absence of NAFLD.

Design, Setting, And Participants: This retrospective, population-based, nationwide cohort study used an active-comparator new-user design.

Risk of myocardial infarction, heart failure, and cerebrovascular disease with the use of valsartan, losartan, irbesartan, and telmisartan in patients.

There is a lack of studies comparing the risk of cardio-cerebrovascular disease between angiotensin receptor blockers (ARBs) of different half-lives. We aimed to compare the risks of myocardial infarction (MI), heart failure (HF), and cerebrovascular disease with the use of valsartan, losartan, irbesartan, and telmisartan with different half-lives in a national claim-based retrospective cohort of patients aged ≥ 40 years with hypertension. To establish a cohort exposed to valsartan, losartan, irbesartan, or telmisartan, we performed propensity score (PS) matching and used an as-treated approach to evaluate exposure.

Heterogeneous distributions in clinical events preceding anticoagulant treatment nonpersistence in patients with venous thromboembolism stratified by active cancer: A nationwide cohort study.

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.

Real-world data emulating randomized controlled trials of non-vitamin K antagonist oral anticoagulants in patients with venous thromboembolism.

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).

Sodium-Glucose Cotransporter 2 Inhibitors vs Incretin-Based Drugs and Risk of Fractures for Type 2 Diabetes.

Importance: Postmenopausal individuals with type 2 diabetes are susceptible to fractures due to the interaction of elevated blood glucose levels and a deficiency of the hormone estrogen. Despite continued concerns of fracture risks associated with sodium-glucose cotransporter 2 inhibitors (SGLT2i), existing evidence in this high-risk population is lacking.

Objective: To assess the risk of fractures associated with SGLT2i vs incretin-based drugs of dipeptidyl-peptidase 4 inhibitors (DPP4i) and glucagon-like peptide 1 receptor agonists (GLP1RA), separately, in postmenopausal individuals with type 2 diabetes.

Safety of sodium-glucose co-transporter-2 inhibitors on amputation across categories of baseline cardiovascular disease and diuretics use in patients with type 2 diabetes.

Aim: To assess the risk of amputation associated with sodium-glucose co-transporter-2 inhibitors (SGLT2is) among patients with type 2 diabetes, across categories of baseline cardiovascular disease (CVD) and diuretic use (DU).

Materials And Methods: We conducted an active comparator, new-user cohort study using Korea's nationwide claims data (2015-2020). The study cohort consisted of patients with type 2 diabetes who initiated SGLT2is or dipeptidyl peptidase-4 inhibitors (DPP4is).

Dynamic Patterns and Persistence of Anticoagulation Therapy in Patients with Venous Thromboembolism in South Korea: A Nationwide Cohort Study.

Background:  Venous thromboembolism (VTE) is associated with increased morbidity, mortality, and health care expenditure. However, the comprehensive utilization of anticoagulation therapy in patients with VTE, especially regarding active cancer, in real-world practice remains unclear.

Objective:  To describe the prescription, persistence, and patterns of anticoagulation therapy among patients with VTE stratified according to active cancer.

Comparative safety of bedaquiline and delamanid in patients with multidrug resistant tuberculosis: A nationwide retrospective cohort study.

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.

Validating an approach to overcome the immeasurable time bias in cohort studies: a real-world example and Monte Carlo simulation study.

Background: Immeasurable time bias arises from the lack of in-hospital medication information. It has been suggested that time-varying adjustment for hospitalization may minimize this potential bias. However, whereas we examined this issue in one case study, there remains a need to assess the validity of this approach in other settings.

Global Epidemiology of Hip Fractures: Secular Trends in Incidence Rate, Post-Fracture Treatment, and All-Cause Mortality.

In this international study, we examined the incidence of hip fractures, postfracture treatment, and all-cause mortality following hip fractures, based on demographics, geography, and calendar year. We used patient-level healthcare data from 19 countries and regions to identify patients aged 50 years and older hospitalized with a hip fracture from 2005 to 2018. The age- and sex-standardized incidence rates of hip fractures, post-hip fracture treatment (defined as the proportion of patients receiving anti-osteoporosis medication with various mechanisms of action [bisphosphonates, denosumab, raloxifene, strontium ranelate, or teriparatide] following a hip fracture), and the all-cause mortality rates after hip fractures were estimated using a standardized protocol and common data model.

Neonatal and maternal adverse outcomes and exposure to nonsteroidal anti-inflammatory drugs during early pregnancy in South Korea: A nationwide cohort study.

Background: Existing 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.

Association of adverse respiratory events with sodium-glucose cotransporter 2 inhibitors versus dipeptidyl peptidase 4 inhibitors among patients with type 2 diabetes in South Korea: a nationwide cohort study.

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.

Association Between Proton Pump Inhibitor Use During Early Pregnancy and Risk of Congenital Malformations.

Importance: Proton pump inhibitors (PPIs) are increasingly used during pregnancy; however, several observational studies have raised concerns about an increased risk of specific types of congenital malformations.

Objective: To examine the association between PPI exposure during early pregnancy and the risk of congenital malformations.

Design, Setting, And Participants: This population-based cohort study used data from the National Health Insurance Service-National Health Information Database of South Korea (2010-2020); sibling-controlled analyses were conducted to account for familial factors.