Behçet disease (BD) is a multisystem inflammatory disorder characterized by a chronic relapsing course. Because immunosuppressive therapy is the mainstay of BD treatment, its use in transplant recipients may attenuate typical clinical manifestations, thereby complicating diagnosis. We report a case of new-onset intestinal BD that developed in a 28-year-old man 3 years after deceased donor kidney transplantation, following an episode of cytomegalovirus colitis. The patient presented with recurrent abdominal pain, diarrhea, weight loss, and hematochezia. Colonoscopy revealed a deep, oval ulcer with well-demarcated, edematous, and nodular margins in the terminal ileum as well as healed scars near the ileocecal valve, findings consistent with intestinal BD.The patient’s symptoms improved after 2 weeks of therapy with colchicine, mesalazine, and mercaptopurine. This case highlights the rare, de novo development of intestinal BD years after kidney transplantation. Intestinal BD should be considered in transplant recipients presenting with unexplained abdominal pain or diarrhea.

OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic had direct effects on population health through infection and morbidity, as well as indirect effects on population mental health. We estimated the network structure of post-traumatic stress symptoms (PTSS) and depressive symptoms throughout the pandemic in Korea and aimed to identify the most central and bridging symptoms. METHODS: Participants aged 30–64 years completed mental health surveys across 3 phases of the COVID-19 pandemic: March 2020 (n=1,925), February–March 2021 (n=1,754), and December 2021–January 2022 (n=1,595). Using PTSS and depressive symptom data, we conducted network analyses, and the primary measures of symptom importance (centrality) were expected influence and bridge expected influence. RESULTS: In the comorbidity network, although the most central symptoms fluctuated over the course of the pandemic, sleep problems were consistently identified as the most influential bridge symptoms throughout. The symptom network structure differed between the subacute and chronic phases of the pandemic. CONCLUSIONS We found evidence of changes in the network structure of PTSS and depressive symptoms, even as sleep problems retained a consistent role as a bridging symptom. Although overall network structures varied across phases of the pandemic, the bridging role of sleep-related symptoms remained consistently strong, suggesting that sleep problems may represent a general and enduring mechanism underlying PTSS–depression comorbidity. During future pandemics, prompt screening for sleep problems may help prevent the development of comorbidity between PTSS and depressive symptoms.

Background and Objectives: Clinical characteristics and outcomes in acute heart failure (AHF) vary by phenotype. We assessed phenotype-specific features, treatment patterns, and outcomes in a nationwide Korean cohort. Methods: The Korean Heart Failure III registry prospectively enrolled 7,351 AHF admissions at 47 hospitals. Among 6,777 patients with available left ventricular ejection fraction (EF), phenotypes were defined as heart failure with reduced EF (HFrEF, ≤40%), mildly reduced EF (HFmrEF,41–49%), or preserved EF (HFpEF, ≥50%). The primary endpoint was a 12-month composite of all-cause death or heart transplantation, evaluated from index admission and, among hospital survivors, from discharge. We used inverse probability weighting (multinomial generalized boosted models with stabilized, trimmed weights) and weighted Cox proportional-hazards models to estimate hazard ratios (HRs). Results: Phenotype distribution was 58.9% HFrEF, 13.6% HFmrEF, and 27.5% HFpEF. Crude 12-month composite rates from index admission were 13.4% (HFrEF), 12.7% (HFmrEF), and 16.8% (HFpEF). After weighting, from index admission, HFmrEF (HR, 0.892; 95% confidence interval [CI], 0.731–1.088) and HFpEF (HR, 1.101; 95% CI, 0.939–1.291) did not differ from HFrEF; from discharge, HFpEF had modestly higher risk (HR, 1.207; 95% CI, 1.008–1.445) whereas HFmrEF did not (HR, 1.039; 95% CI, 0.844–1.279). Hyponatremia and chronic kidney disease were consistent adverse markers, while angiotensin-converting enzyme inhibitor/ angiotensin II receptor blocker use at discharge was protective. Conclusions Across the EF spectrum, phenotypes showed distinct profiles and risk. Postdischarge risk was modestly higher in HFpEF, supporting phenotype-tailored care and systematic discharge optimization in Korean patients with AHF.

Background and Objectives: We evaluated 20-year trends in heart failure (HF) epidemiology in Korea to quantify changes in its burden from 2002 to 2023. Methods: A nationwide analysis was conducted using a random 50% sample from the Korean National Health Information Database linked to mortality records (2002–2023). HF was defined using diagnostic codes recorded as a primary or secondary condition. We calculated crude and age-standardized rates of prevalence, incidence, hospitalization, and mortality. Survival was assessed using the Kaplan–Meier method, stratified by inpatient versus outpatient diagnosis.Trends in heart transplantation and left ventricular assist device implantations were also examined. Results: By 2023, approximately 1,750,228 individuals had HF (3.41% prevalence). The age-standardized prevalence has more than doubled from 2002 to 2023. The crude incidence increased over time; the age-standardized incidence remained stable in men and declined in women.Hospitalization rates for any cause or secondary HF diagnoses have increased substantially, whereas primary HF hospitalization rates have remained relatively stable. The annual mortality rate in patients with HF was approximately 6.0% in 2023, being markedly higher in older adults.Although short-term survival has improved, particularly in hospitalized patients, long-term survival remains limited. Use of advanced therapies significantly increased. Conclusions The burden of HF in Korea has increased substantially over the past two decades, driven primarily by population aging and improved survival rather than increasing age-adjusted incidence. Despite therapeutic advances, hospitalization and long-term mortality rates remain high, highlighting the need for comprehensive HF strategies in aging societies.

Heart failure (HF) prevalence and associated socio-economic costs have risen rapidly in Korea, creating urgent demand for a national, standardized prospective registry to support quality monitoring, outcome comparison, and real-world evidence. Standardized data definitions are essential for valid comparisons across studies and healthcare settings. We created a unified national HF cohort by integrating the two largest Korean registries, KorAHF (2011–2014;n=5,625) and KorHF III (2018–2023; n=7,351), yielding 12,976 hospitalized HF patients. Because heterogeneous variable definitions impeded direct comparisons, we implemented a harmonization pipeline across demographic, clinical, imaging, biomarker, therapeutic, and outcome domains, aligned with international standards and reinforced by systematic data quality checks.A multidisciplinary panel then conducted a structured decision process to produce the Korean HF Standard Dataset, a tiered and interoperable variable set spanning six domains: demographics, presentation at admission, in-hospital events and comorbidities, discharge status, outpatient follow-up, and readmission events. This integrated platform and standardized variables enable precise identification of HF patient phenotypes and prognostic factors, establishing an evidence-based foundation for disease management. This supports an analysis of temporal changes in treatment patterns and outcomes, generates data to inform future clinical practice guidelines, and provides a practical basis for planning large, continuous, prospective HF registries. Furthermore, it also facilitates pragmatic, registry-based randomized clinical trials and unmet-needs assessments that can guide national health policy. Establishing a foundation for future linkage with national health databases, this platform will allow for enhanced accuracy, comparability, and representativeness, powering quality improvement initiatives and population-level monitoring of Korea’s growing HF burden.

Background: Although various surface modifications enhance titanium (Ti) implant osseointegration, achieving rapid bone formation comparable to native healing remains challenging. Current strategies primarily focus on micro-scale topography, often overlooking the critical role of macroscopic three-dimensional (3D) architecture in osteoconduction. Methods: We hypothesized that mimicking native bone’s porous architecture is key to accelerating osseointegration. First, we verified the impact of structural continuity by comparing standard Ti implants with decellularized bone grafts in a mouse calvaria defect model. Subsequently, we developed a biomimetic polycaprolactone (PCL)-based 3D architectural cover (Cover-type) and evaluated its osseointegration efficacy in a rat femur model against conventional Ti implants. Results: The mouse study confirmed that decellularized bone integrated significantly faster than Ti, highlighting the necessity of 3D continuity. In the rat model, micro-computed tomography analysis indicated a clear trend of increased bone formation in the Cover-type group, though statistical significance was limited by sample size. However, histological analysis confirmed a statistically significant enhancement in bone-to-implant contact compared to controls (P<0.05). The PCL structure served as a scaffold for cell migration, effectively bridging the implant-bone gap. Conclusions These findings suggest that providing a bone-like 3D environment via a PCL cover may enhance histological osseointegration, rather than relying solely on surface chemistry.

Background: To investigate the fracture risks associated with anti-diabetic drugs in older women with type 2 diabetes mellitus (T2DM), who are particularly susceptible to skeletal fragility. Methods: Using data from the Korean National Health Insurance Service, this nested case-control study included 10,104 older women with T2DM and osteoporotic fractures (aged 66.5±3.4 years) matched in a 1:3 ratio with controls by birthdate, Charlson Comorbidity Index, and cohort entry date. We analyzed the odds of major osteoporotic fracture (MOF), vertebral fracture (VF), and non-VF (NVF) in users of sulfonylurea, thiazolidinedione (TZD), dipeptidyl peptidase-4 inhibitor, and sodium-glucose cotransporter 2 inhibitor (SGLT2i), compared to metformin (Met)-only users using multivariable logistic regression. Results: During a follow-up period of 3.8±2.8 years, TZD users had a higher risk of MOF than Met-only users (odds ratio [OR], 1.35; 95% confidence interval [CI], 1.19-1.53; P<0.001). Risks of VF and NVF were also increased in the TZD group (OR, 1.21; 95% CI 1.03-1.42; P=0.022 and OR, 1.32; 95% CI 1.14-1.52; P<0.001, respectively). No significant differences were observed in other drug groups. The increased risk of VF and NVF in the TZD group were particularly pronounced in patients with normal or osteopenic bone mineral density (BMD) and in those with normal body mass index (BMI), respectively. Conclusions In older women with T2DM, TZD use was associated with increased VF and NVF risks, particularly among those with normal or osteopenic BMD and normal BMI. SGLT2i showed no increased risk, but further large-scale studies are needed to confirm its skeletal safety.

Purpose: While the benefit of neoadjuvant chemotherapy (NAC) has been established in human epidermal growth factor receptor 2 (HER2)-positive and triple-negative breast cancers, its effectiveness in achieving pathological complete response (pCR) and optimal patient selection in estrogen receptor (ER)-positive, HER2-negative breast cancers remain less clearly defined. This study aimed to identify immunohistochemistry (IHC)-based predictors of pCR and to develop a scoring model for ER-strong positive/HER2-negative breast cancer. Methods: Data from a prospective cohort were retrospectively analyzed. We included 522 patients with ER-strong positive/HER2-negative tumors who received NAC and surgery between 2008 and 2021. IHC markers including progesterone receptor (PR), Ki-67, epidermal growth factor receptor (EGFR), cytokeratin 5/6 (CK5/6), and p53 were evaluated to identify predictors of pCR. Independent predictors of pCR from multivariate logistic regression were used to develop a weighted 4-point model. Model performance was assessed using receiver operating characteristic analysis. The prognostic impact of pCR was evaluated using KaplanMeier and Cox regression analyses. Results: Independent predictors of pCR included PR-negative status, positivity for basallike markers (EGFR or CK5/6), and Ki-67 ≥ 50%. The scoring model demonstrated good discrimination for pCR (area under the curve = 0.754). pCR rates increased stepwise, with scores of 4.9% (low), 10.7% (intermediate), and 36.2% (high). In the high-score group, pCR was significantly associated with improved disease-free survival (hazard ratio [HR], 0.09; p = 0.023) and distant metastasis-free survival (HR, 0.11; p = 0.035), whereas no significant survival differences according to pCR status were observed in the low and intermediate score groups. Conclusion This IHC-based model predicts pCR and helps identify subgroups in which pCR is associated with meaningful survival benefit following NAC in ER-positive/HER2-negative breast cancers. High-scoring patients may benefit from NAC, while patients with low- or intermediatescores may be better managed with surgery and endocrine therapy. This model may support personalized treatment decisions regarding NAC.

Purpose: Lobular carcinoma In Situ (LCIS) is a noninvasive lesion associated with an increased risk of invasive cancer. Since its removal from the tumor, node, metastasis classification in the 8th edition of the American Joint Committee on Cancer (AJCC) guidelines, the clinical management of LCIS has shifted from surgery to surveillance. However, studies focusing on the risk and associated factors for invasive cancer development in pure LCIS without ductal carcinoma In Situ (DCIS) or invasive cancer remain limited. Methods: We retrospectively analyzed 106 patients diagnosed with pure LCIS between 2008 and 2018. This study evaluated the effect of tamoxifen use and histologic type on the development of invasive cancer. Results: All 106 patients underwent surgery, and nine (8.5%) developed invasive cancer over a median follow-up of 67.5 months. The incidence of invasive cancer was lower in the tamoxifen group (6.3%, n = 4) than in the non-tamoxifen group (11.9%, n = 5), although this difference was not statistically significant (p = 0.266). Pleomorphic LCIS had a significantly higher incidence of invasive cancer (30.0%, n = 3) than classic LCIS (6.3%, n = 6) (p = 0.045).Multivariable Cox regression analysis showed no significant difference in the risk of invasive cancer according to tamoxifen use (hazard ratio [HR], 2.031; 95% confidence interval [CI], 0.544–7.579; p = 0.292). However, pleomorphic LCIS showed a trend toward an increased risk of invasive cancer compared to classic LCIS (HR, 3.856; 95% CI, 0.922–16.126; p = 0.064). Conclusion Postoperative tamoxifen did not significantly lower invasive cancer development in patients with pure LCIS. Pleomorphic LCIS may carry a higher risk than classic LCIS. These findings require tailored follow-up and treatment strategies based on the histologic subtype of LCIS.