National Health Insurance Service

The disease burden of respiratory syncytial virus (RSV) infection in Japanese adults has been attracting attention. Nasopharyngeal swabs were collected from 141 patients aged 18 years and older who visited a Japanese clinic from August 2024 to July 2025 with symptoms of an acute respiratory infection. These samples were tested using rapid immunochromatographic antigen tests for SARS-CoV-2, influenza viruses A and B, and RSV. The results showed that 32 patients tested positive for SARS-CoV-2, 31 for influenza virus A, and one for influenza virus B, whereas no RSV-positive patients were detected. Compared with five previous reports using polymerase-chain reaction (PCR) testing (RSV-positive: 88 of 2974 patients), the number of RSV-positive patients was lower (chi-squared test p=0.04123), suggesting that the rapid immunochromatographic antigen test is not useful for diagnosing RSV infections in adults in Japan.

Background/Objective: Acinetobacter baumannii is an opportunistic pathogen responsible for various healthcare-associated infections, particularly in critically ill patients. The emergence and rapid spread of multidrug- and extensively drug-resistant strains, notably carbapenem-resistant A. baumannii (CRAB), threaten global health. We aimed to investigate the clonal distribution, antimicrobial resistance profiles, and resistance determinants of CRAB bloodstream isolates in Korean hospitals to identify emerging high-risk clones and their potential clinical impact. Methods: Sequence types (STs) were determined using the Oxford multilocus sequence typing scheme, and antimicrobial susceptibility profiles and resistance determinants were evaluated. Results: We analyzed 812 CRAB bloodstream isolates collected from nine South Korean tertiary hospitals between 2016 and 2020. The isolates were classified into 39 STs, with ST191 (n = 245) and ST369 (n = 192) being the most prevalent. Between 2016 and 2020, ST369 increased from 2.6% to 37.9%, while ST195, first detected in 2018 (0.5%), increased to 19.0%; however, ST191 declined from 45.2% to 19.0%. Most CRAB infections were hospital-acquired (91.6%, 744 of 812), predominantly affecting men aged ≥51 years, particularly the 71-80-year-olds. Resistance rates were ≥80% for ampicillin-sulbactam and ciprofloxacin. blaOXA-23 was detected in 807 isolates, confirming its central role in carbapenem resistance. ST195 exhibited higher resistance to minocycline (29.4%) than did the other STs. Conclusions: Dynamic clonal shifts and high antimicrobial resistance exist among CRAB isolates in Korean hospitals, with the rapid emergence of ST195 and ST369 increasing clinical challenges. Continuous epidemiological surveillance and targeted infection control measures are essential to control the spread of high-risk CRAB clones.

Although the association between sarcopenia and depression is well-established, studies exploring the link between low muscle mass and depression in the general population are limited. This study aimed to investigate whether participants’ muscle mass proportion was associated with the prevalence of depression. Additionally, we examined whether individuals with lower muscle mass exhibited greater symptom burden, using both categorical and continuous analytic approaches. Data from the 2022 Korea National Health and Nutrition Examination Survey were used for this study. Altogether, 4185 participants who completed the Patient Health Questionnaire-9 were included. Muscle mass was measured using the bioelectrical impedance analysis method, and the participants were divided into low, medium, and high groups based on the proportion of appendicular muscle mass relative to body weight. The association between low muscle mass and depression was analyzed using multiple logistic regression. Men in the low muscle mass group exhibited 1.99 times higher odds of depression, (odds ratio = 1.99, 95% confidence interval = 1.03–3.85) and 1.61 times higher in women (OR = 1.61, 95% CI = [1.00-2.58]) using the medium muscle mass proportion group as a reference. Furthermore, in continuous analyses, higher muscle mass proportion was inversely associated with PHQ-9 scores in both men and women, suggesting a negative relationship between muscle mass proportion and depressive symptom burden. This study identified an association between reduced muscle mass and depression. Future prospective studies should explore whether this relationship is causal and determine whether interventions to increase muscle mass can help reduce the prevalence of depression. Such investigations could offer valuable insights into population-level strategies for mitigating depression.

BackgroundAntipsychotics are frequently prescribed off-label to manage behavioral and psychological symptoms of dementia but pose safety risks in older adults, including a 1.5–2.0-fold increased risk of mortality. The coronavirus disease (COVID-19) pandemic disrupted dementia care, increasing reliance on pharmacologic treatments.ObjectiveThis study aimed to evaluate whether the COVID-19 pandemic was associated with changes in the prevalence of antipsychotic prescribing among patients with dementia.MethodsUsing the Korean National Health Insurance Database, this study analyzed a random 50% sample of eligible individuals aged ≥60 years diagnosed with dementia between 2016 and 2021 (n = 876,158; 9.8 million person-observations). Outcomes included the likelihood, duration, and number of antipsychotic prescriptions issued, characterizing pharmacologic management of dementia. Interrupted time series analysis assessed associations between the pandemic and relative changes in these outcomes, adjusting for demographic factors, comorbid burden, and seasonality.ResultsAfter the pandemic onset, there were relative slope increases per quarter of 1.5%, 3.2%, and 0.4% in the likelihood, duration, and number of prescriptions, respectively (all p < 0.001; pre-pandemic levels: 0.172 patients prescribed, 12.97 days, and 18.10 prescriptions per person-quarter). Antipsychotic prescriptions decreased by 1.6% (p < 0.001) during the first quarter after the outbreak but subsequently showed a progressive increase, reflecting prolonged care disruption after initial access barriers.ConclusionsThe COVID-19 pandemic was associated with increased antipsychotic prescribing among patients with dementia. To mitigate similar effects in future public health crises, governments and healthcare providers should strengthen mental health support, non-pharmacological interventions, telehealth continuity, and tailored prescribing guidelines.

Introduction: Despite previous studies suggesting an association between venous outflow (VO) and clinical outcomes, the relationship between VO status and comprehensive efficacy and safety outcomes after endovascular thrombectomy (EVT), including the influence of systolic blood pressure variability (BPV), remains unclear. Patients and Methods: We performed a secondary analysis of the OPTIMAL-BP trial. Patients were categorized into unfavorable VO (cortical vein opacification score (CVOS) &lt;3) or favorable VO (CVOS ≥3). Efficacy outcomes included modified Rankin Scale (mRS) scores of 0–2 and 0–3 at three months, excellent NIHSS recovery, and final infarction volume (FIV). Safety outcomes consisted of any intracerebral hemorrhage (ICH), symptomatic ICH, any parenchymal hemorrhage (PH), PH type 2, and subarachnoid hemorrhage (SAH). BPV parameters, including time rate (TR), standard deviation, coefficient of variation, and variation independent of mean, were calculated within the first 24 hours after randomization. Results: Among 226 patients, unfavorable VO significantly correlated with lower odds of achieving mRS 0–2 (adjusted odds ratio [aOR], 0.44 [95% CI, 0.22–0.87]), mRS 0–3 (aOR, 0.39 [0.20–0.73]), excellent NIHSS recovery (aOR, 0.40 [0.15–0.95]), and increased FIV (adjusted coefficient, 37.18 [14.81–59.55]). It was also associated with increased odds of any ICH (aOR, 2.28 [1.20–4.39]), symptomatic ICH (aOR, 9.82 [3.12–39.40]), any PH (aOR, 6.08 [2.76–14.07]), PH type 2 (aOR, 174.59 [14.41–7276.24]), and SAH (aOR, 2.44 [1.13–5.29]). Only increased systolic BPV TR correlated significantly with poorer efficacy outcomes in unfavorable VO group. Sensitivity analyses using a Bayesian approach yielded results consistent with the primary analysis Conclusion: Unfavorable VO was associated with poorer clinical and safety outcomes after successful recanalization following EVT and increased post-EVT BPV further worsened clinical outcomes only in unfavorable group. These finding suggest that BPV modulation may improve prognosis in stroke patients with unfavorable VO.

Background/Objectives: With the global rise in chronic diseases among older adults, rehabilitation services have become essential, particularly for those with cerebrovascular and central nervous system (CNS) disorders, which lead to significant long-term disabilities. To determine the impact of designated rehabilitation medical institutions on the readmission rates of older patients with CNS disorders who receive surgical interventions. Methods: This was a population-based cohort study. Data was obtained from the National Health Insurance Service database (2002-2019). Fifteen designated institutions participated in the pilot project for convalescent rehabilitation. We analyzed the data of 1019 patients before and after the implementation of the designated rehabilitation institution. The study sample included (1) patients admitted to 15 designated institutions participating in the pilot project for convalescent rehabilitation and (2) patients diagnosed with conditions classified under the rehabilitation patient group, Rehabilitation Impairment Category 1 to 7. The intervention was the pilot project for designated rehabilitation institutions, launched in October 2017. The primary outcome of interest was the readmission rate of older patients with CNS disorders who received surgical interventions. Interrupted time series analysis with segmented regression was used to assess changes in the 30-day readmission rates. Results: Post-intervention, an 8% reduction in 30-day readmission rates (estimate, 0.9225; 95% confidence interval: 0.9129-0.9322, p < 0.0001) was observed. Subgroup analysis showed a significant decline in readmission rates across various patient groups, including those with disabilities, high Charlson Comorbidity Index scores, and extended hospital stays. The regions outside Seoul (capital city), particularly Gyeonggi/Incheon (areas around Seoul) and other areas (i.e., rural), also showed a significant decrease in readmission trends after the intervention. Conclusions: Designated rehabilitation medical institutions led to a significant reduction in readmission rates of older patients with CNS disorders, suggesting that these institutions effectively support recovery and reduce the burden of readmission for patients with severe conditions and those residing in non-capital cities.

Gallstone formation is a potential long-term complication of gastrectomies. However, data on symptomatic gallstone disease after gastrectomy for gastric cancer are limited. This nationwide population-based study aimed to determine the incidence and risk factors of symptomatic gallstone disease requiring invasive intervention. This nationwide cohort study was based on claims data from the Korean National Health Insurance Service Database. The study included 90456 patients who underwent gastrectomy for gastric cancer between 2007 and 2020 after excluding individuals with prior gallbladder disease, liver dysfunction, or ursodeoxycholic acid use. The primary outcome was symptomatic gallstone disease that required invasive intervention (cholecystectomy or endoscopic/percutaneous biliary procedures). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using the Cox proportional hazards analysis. During a mean follow-up of 7.5years, 6465 patients (7.1%) developed symptomatic gallstone disease requiring invasive intervention, with 5-year and 10-year cumulative incidences of 4.9% and 8.9%, respectively. Independent risk factors included age 60-79years (HR 1.49, 95% CI 1.25-1.78) and ≥ 80years (HR 2.10, 95% CI 1.69-2.61), body mass index ≥ 25 kg/m2 (HR 1.25, 95% CI 1.19-1.32), hypertension (HR 1.10, 95% CI 1.04-1.16), diabetes mellitus (HR 1.10, 95% CI 1.04-1.17), Charlson Comorbidity Index ≥ 6 (HR 1.32, 95% CI 1.23-1.43), total gastrectomy (HR 1.80, 95% CI 1.70-1.90), and adjuvant chemotherapy (HR 2.11, 95% CI 1.98-2.24). Female sex (HR 0.76, 95% CI 0.71-0.82), pylorus-preserving gastrectomy (HR 0.47, 95% CI 0.33-0.67), and laparoscopic surgery (HR 0.85, 95% CI 0.81-0.90) were protective. Symptomatic gallstone disease requiring invasive intervention occurred in 7.1% of the patients after gastrectomy for gastric cancer, representing a substantial increase compared to the general population. Pylorus-preserving gastrectomy and laparoscopic surgery were associated with a lower risk, suggesting that the surgical approach may influence the long-term gallstone risk.