This study aimed to determine the prevalence of human epidermal growth factor receptor 2 (HER2)–ultralow breast cancer among cases initially classified as HER2 immunohistochemistry (IHC) 0 and assess interobserver variability in interpreting low-level HER2 expression. Methods: In this multicenter retrospective study, all invasive breast cancer cases diagnosed between January and December 2022 across 10 Korean institutions were retrieved. Institutional pathologists reexamined HER2 IHC slides originally reported as IHC 0 according to the 2018 American Society of Clinical Oncology/College of American Pathologists guidelines and reclassified them as HER2-null (0), HER2-ultralow (0+), or HER2-low (1+). Slides from 10% of HER2-null and HER2-ultralow cases were digitized for central review and independently assessed by two pathologists, with discrepancies resolved by consensus. Results: Among 8,026 cases, 2,836 cases (35.5%) were initially reported as IHC 0. Upon re-review, 1,673 (59.0%), 1,139 (40.2%), and 24 (0.8%) cases were reclassified as HER2-null, HER2-ultralow, and HER2-low, respectively. The prevalence of HER2-ultralow breast cancer varied considerably across institutions (23.7%–78.1%). Central review of 268 digitized cases showed concordance in 193 cases (72.0%). Among the 75 discordant cases, 54 tumors (72.0%) were upgraded from HER2-null to HER2-ultralow, and 18 (24.0%) tumors were upgraded from HER2-ultralow to HER2-low. Furthermore, two tumors (2.7%) were downgraded from HER2-ultralow to HER2-null. Conclusions: Approximately 40% of cases initially categorized as IHC 0 were reclassified as HER2-ultralow. The substantial inter-institutional variability observed in interpreting low-level HER2 expression highlights the need for standardized training and quality assurance to ensure accurate identification of patients eligible for HER2-targeted antibody–drug conjugates.

The COVID-19 pandemic has adversely affected the mental health of the global population. This study aimed to assess the acute and persistent symptoms of depression, as well as factors related to their manifestation, through a longitudinal study design. A total of 1,492 community-dwelling adults from an online public panel across three regions were evaluated at baseline, with 908 adults (60.9%) followed up after six months. Depression symptoms were evaluated using Patient Health Questionnaire-9 (PHQ-9). Participants also completed self-administered questionnaires on sociodemographic information, psychosocial experiences related to COVID-19, the UCLA Loneliness Scale, and the Korean version of the Gratitude Questionnaire (K-GQ-6).The prevalence of acute and persistent depression symptoms was 8.4% and 12.0%, respectively. Multivariate logistic regression analysis identified changes in predictors of depression over time, with younger age and self-isolation experience found to be associated with acute depression. Factors such as underlying mental illness, eating and sleeping disturbances, loneliness, and COVID-19-related stress emerged as significant risk factors for persistent depression. A disposition toward gratitude was identified as a protective factor for persistent depressive symptoms. These findings suggest that during any long-term pandemic crisis such as COVID-19, timely support and attention are essential for vulnerable populations, including young people and individuals with mental health conditions, to prevent depression. Specifically, promoting daily routines such as regular eating and sleeping patterns, and managing COVID-19-related stress may be critical in preventing persistent depression. Additionally, psychological support that reduces loneliness and fosters gratitude may help mitigate depression risk.

Objectives: This study aimed to investigate the impact of behavioral and psychological symptoms (BPS), assessed by the neuropsychiatric inventory (NPI) total score, on instrumental activities of daily living (IADL) performance in patients with mild cognitive impairment. Methods: Ninety-two patients diagnosed with mild cognitive impairment who visited a university hospital dementia clinic were recruited. Assessments included the Korean version-Mini Mental State Examination, NPI, Korean-IADL (KIADL), and Short Form of Geriatric Depression Scale-Korean version. Correlation and hierarchical multiple regression analyses were performed to analyze the relationship between BPS and IADL. Results: The mean age of participants was 74.61±5.86 years. K-IADL scores significantly correlated with age (r=0.347, p<0.001) and NPI total score (r=0.265, p<0.05). Hierarchical regression analysis showed that the addition of the NPI total score significantly increased the explained variance of functional decline (R 2 =0.197, F=5.332, p<0.001), with age (β=0.354, p<0.001) and NPI total score (β=0.248, p<0.05) identified as independent predictors in patients with mild cognitive impairment. Conclusions The overall severity of BPS exerts a detrimental effect on IADL function in mild cognitive impairment patients, independent of age and cognitive status. These results underscore the clinical importance of evaluating the cumulative burden of BPS to predict functional prognosis and implement early interventions.

Objective: This study examined whether baseline levels of 14 serum biomarkers predicted antidepressant remission differently by sex at 12 weeks and 12 months. Methods: In a prospective cohort, 1,086 outpatients with depressive disorders received stepwise antidepressant treatment following a naturalistic protocol. Baseline serum samples were analyzed for biomarkers from six systems: immune (high-sensitivity C-reactive protein, tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, interleukin-4, interleukin-10), metabolic (leptin, ghrelin, total cholesterol), neurotrophic (brain-derived neurotrophic factor), neurotransmitter (serotonin), endocrine (cortisol), and nutritional (folate, homocysteine). Remission, defined as a Hamilton Depression Rating Scale scores ≤ 7, was assessed at 12 weeks and 12 months. Logistic regression models with biomarker-by-sex interaction and stratified analyses were used, adjusting for clinical covariates. Results: Higher baseline serotonin predicted 12-week remission in males but not in females. At 12 months, lower leptin and higher folate predicted remission only in males, while lower cortisol predicted remission only in females. These showed significant biomarker-sex interactions. No sex-specific interactions were found for immune markers. Conclusion Baseline serum biomarkers across biological systems showed sex-specific associations with treatment outcomes. Neurotransmitter, metabolic, endocrine, and nutritional markers may offer predictive value for sex-tailored, biomarker-informed treatment strategies in depression.

Objective: Impact of Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) changes on the criteria for schizophrenia (SZ) has been reported to be minimal in previous studies. However, this could be different in first-episode schizophrenia spectrum disorders (FE-SSDs). We investigated what proportion of patients with FE-SSDs was diagnosed based on the sole presence of bizarre delusions (BDs) or first rank auditory hallucinations (FRAHs). Their alternative diagnosis by the DSM-5 was established and diagnostic stability over 1-year was identified. Methods: This was a retrospective review study on the medical records, case report forms for the subjects with FE-SSDs (n=404) participated in the Korea Early Psychosis Study. The two Japanese sites reviewed retrospectively only medical records of the subjects with FE-SSDs (n=103). We used three different definitions of BDs (strict, narrow, and broad) and specified subtypes of Other Specified Schizophrenia spectrum and Other psychotic disorders (OSSOs). To ensure inter-rater reliability between the hospitals, regular zoom meetings were held. Results: Forty (7.89%) subjects out of 507 were found to be diagnosed as SSDs based on the sole presence of BDs or FRAHs. All these patients met the criteria of OSSOs and were classified as having pure delusion (n=22), delusion with attenuated auditory hallucinations (AHs) (n=5), pure AHs (n=3) and AHs with attenuated delusion (n=10). The patients with first and second subtypes (n=27) were found to have BDs. The BDs fulfilled mostly strict definitions or satisfied the next broadest definition. The diagnostic stability of FE-OSSOs and its subgroups (first and second subtypes) over 1-year was substantially high (70.27% and 84% respectively). Conclusion These findings suggest that more rigorous diagnostic assessment should be performed especially to differentiate OSSOs from SZ in patients with FE-SSDs and more refined classification of the subtypes for OSSOs considered in the next DSM revision.

Digital therapeutics (DTx) are emerging as a transformative innovation in healthcare offering evidence-based digital interventions for the treatment, management, and prevention of various diseases and disorders. In Korea, DTx have gained significant attention as potential solutions to the increasing burden of chronic diseases and mental health conditions. However, the Korean DTx market faces several challenges that hinder its widespread adoption and integration into the national healthcare system. This study provides a comprehensive analysis of the current state of the DTx market in Korea, identifies the key challenges impeding its growth, and proposes strategies for overcoming these obstacles. This study utilized a literature review and market analysis approach to examine the latest research, industry reports, and regulatory documents related to DTx. The analysis focused on three primary areas: (1) the current regulatory landscape, (2) technological advancements and challenges, and (3) economic and commercial factors influencing DTx adoption in Korea. A comparative analysis of global regulatory practices was also conducted to identify best practices. The findings revealed that while Korea has made significant strides in supporting DTx development, the market remains in its early stages. The key challenges include underdeveloped regulatory frameworks, issues with data quality and security, and a lack of established reimbursement pathways. We recommend developing tailored regulatory frameworks for DTx, enhancing policy support for small and medium-sized enterprises involved in DTx development, and increasing investments in technological infrastructure. By addressing these challenges, Korea could position itself as a leader in the global DTx market, delivering innovative and effective treatments to enhance patient care and outcomes.

Background and Objectives: Hearing loss significantly affects communication, psychosocial well-being, and quality of life. This study analyzes the National Health Insurance Service database to assess the trends and characteristics of hearing loss in South Korea from 2010 to 2020.Subjects and Method The database encompasses 97% of the Korean population, providing comprehensive data on medical history, prescriptions, and health examinations. The analysis used the World Health Organization’s ICD-10 definitions to categorize hearing loss types and examine their prevalence and incidence across various demographics over 11 years. Results: There was an overall annual increase of 4.62% in diagnosed cases of hearing loss, with the most significant rise among the elderly. The rate of increase accelerated from 3.32% between 2010 and 2014 to 6.49% between 2014 and 2020, corresponding with the improved hearing aid access facilitated by policy changes. Women showed a slightly higher increase than men. The data also indicated a consistent rise in abnormal hearing test results during health examinations, especially in older adults. Conclusion The study highlights an increasing trend in hearing loss diagnoses, driven by an aging population and enhanced detection facilitated by policy changes. These findings emphasize the need for continuous monitoring and targeted health policies to manage hearing loss effectively, offering valuable insights for global health management and policy development.

Background and Objectives: This study aims to analyze trends in hearing disability and the use of hearing rehabilitation devices (hearing aids and cochlear implants) in South Korea over the past 11 years (2010-2020) using data from the National Health Insurance Service (NHIS).Subjects and Method Data were extracted from the NHIS database, covering approximately 97% of the South Korean population. Patients diagnosed with hearing loss were classified using ICD-10 codes. The data were analyzed to determine trends in hearing disability, hearing aid prescriptions, and cochlear implant usage by age, gender, and types and causes of hearing loss. Results: The number of hearing disability patients increased from 170900 in 2010 to 362738 in 2020, with an annual growth rate of 7.95%. The highest increase was observed in the ≥60 age group, with an annual growth rate of 11.04%. Hearing aid prescriptions rose from 4966 in 2010 to 11974 in 2020, showing a 10.45% annual increase. Females showed a higher growth rate in both hearing disability and hearing aid prescriptions compared to males. Cochlear implant prescriptions also increased, particularly among older adults. Conclusion The study highlights a significant rise in hearing disability and the use of hearing aids and cochlear implants in South Korea, especially among the elderly. The findings underscore the importance of early diagnosis and intervention for hearing loss and the need for policy improvements to enhance accessibility and affordability of hearing rehabilitation services. Additional strategies are needed to ensure appropriate hearing rehabilitation for those not yet receiving adequate care.

Objective: Impact of Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) changes on the criteria for schizophrenia (SZ) has been reported to be minimal in previous studies. However, this could be different in first-episode schizophrenia spectrum disorders (FE-SSDs). We investigated what proportion of patients with FE-SSDs was diagnosed based on the sole presence of bizarre delusions (BDs) or first rank auditory hallucinations (FRAHs). Their alternative diagnosis by the DSM-5 was established and diagnostic stability over 1-year was identified. Methods: This was a retrospective review study on the medical records, case report forms for the subjects with FE-SSDs (n=404) participated in the Korea Early Psychosis Study. The two Japanese sites reviewed retrospectively only medical records of the subjects with FE-SSDs (n=103). We used three different definitions of BDs (strict, narrow, and broad) and specified subtypes of Other Specified Schizophrenia spectrum and Other psychotic disorders (OSSOs). To ensure inter-rater reliability between the hospitals, regular zoom meetings were held. Results: Forty (7.89%) subjects out of 507 were found to be diagnosed as SSDs based on the sole presence of BDs or FRAHs. All these patients met the criteria of OSSOs and were classified as having pure delusion (n=22), delusion with attenuated auditory hallucinations (AHs) (n=5), pure AHs (n=3) and AHs with attenuated delusion (n=10). The patients with first and second subtypes (n=27) were found to have BDs. The BDs fulfilled mostly strict definitions or satisfied the next broadest definition. The diagnostic stability of FE-OSSOs and its subgroups (first and second subtypes) over 1-year was substantially high (70.27% and 84% respectively). Conclusion These findings suggest that more rigorous diagnostic assessment should be performed especially to differentiate OSSOs from SZ in patients with FE-SSDs and more refined classification of the subtypes for OSSOs considered in the next DSM revision.

Purpose: To investigate the role of combined periprostatic nerve block (PNB) and intrarectal local anesthesia with heated lidocaine gel (ILAHL) in reducing pain during transrectal ultrasound (TRUS)-guided prostate biopsy, compared with PNB alone. Materials and Methods: We performed a prospective randomized trial with 140 participants who underwent systematic TRUS-guid ed, 12-core prostate biopsy from July 2021 to June 2022. These participants were divided into two groups. Before prostate biopsy, group 1 (n=70) received PNB and group 2 (n=70) received PNB combined intrarectal local anesthesia with 20 mL of heated (40ºC) 2% lidocaine gel. The primary outcome was pain score on a 0–10 visual analogue scale (VAS) at four time points (VAS A: during local anesthesia procedure, VAS B: during probe insertion, VAS C: during biopsy procedure, VAS D: 30 minutes after biopsy). The secondary outcome included adverse events during and after the procedure. Results: Mean pain scores were significantly lower in group 2 than in group 1 at VAS A (2.53 vs. 1.60, p=0.001) and VAS B (2.47 vs.1.49, p<0.001). The mean VAS C pain score in group 2 was significantly less than in group 1 (3.07 vs. 2.20, p=0.001), while there was no significant difference in the mean VAS D pain score between two groups (1.06 vs. 0.89, p=0.318). There were no significant differences in the occurrence of complications in both groups. Conclusions The combination of PNB and ILAHL provides more effective pain control than PNB alone without increase of complication rates in patients undergoing TRUS-guided prostate biopsy.