Journal of Korean Medical Science最新文献

Background: Currently, non-vitamin K-antagonist oral anticoagulant (NOAC) monotherapy has been suggested as the optimal antithrombotic therapy for atrial fibrillation (AF) beyond one year after coronary revascularization. The aim of this study was to compare the outcomes between NOAC monotherapy and NOAC plus antiplatelet combination therapy using real-world data.

Methods: Between 2015 and 2020, patients with AF who had received NOACs beyond one year after coronary revascularization were enrolled from Korean national insurance data. We emulated a pragmatic sequence of trials between the NOAC monotherapy and the antiplatelet combination therapy followed by propensity score matching. The primary endpoint was major adverse cardiac and cerebrovascular events (MACCEs), a composite of all-cause death, myocardial infarction, and stroke.

Results: Among 206,407 person-trials from 4,465 individuals, we compared 3,275 pairs of the monotherapy and the matched combination therapy. During a median follow-up of 1.24 years, the incidence rate of MACCE was 19.4% and 20.0% per patient-year in the monotherapy group and the antiplatelet combination group, respectively (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.88-1.05; P = 0.422). Compared with the antiplatelet combination group, the monotherapy group had a significantly lower incidence rate of major bleeding, defined as intracranial bleeding or gastrointestinal bleeding requiring hospitalization (2.8% vs. 3.6% per patient-year; HR, 0.78; 95% CI, 0.62-0.97; P = 0.024).

Conclusion: As an antithrombotic therapy for AF beyond one year after coronary revascularization, NOAC monotherapy was associated with a similar risk of MACCE and a lower risk of major bleeding compared to NOAC plus antiplatelet combination therapy.

Background: Cancer patients have an increased risk of cardiovascular outcomes and are susceptible to coronavirus disease 2019 (COVID-19) infection. We aimed to assess the cardiovascular safety of COVID-19 vaccination for cancer patients in South Korea.

Methods: We conducted a self-controlled case series study using the K-COV-N cohort (2018-2021). Patients with cancer aged 12 years or older who experienced cardiovascular outcomes were identified. Cardiovascular outcomes were defined as myocardial infarction, stroke, venous thromboembolism (VTE), myocarditis, or pericarditis, and the risk period was 0-28 days after receiving each dose of COVID-19 vaccines. A conditional Poisson regression model was used to calculate the incidence rate ratio (IRR) with 95% confidence interval (CI).

Results: Among 318,105 patients with cancer, 4,754 patients with cardiovascular outcomes were included. The overall cardiovascular risk was not increased (adjusted IRR, 0.99 [95% CI, 0.90-1.08]) during the whole risk period. The adjusted IRRs of total cardiovascular outcomes during the whole risk period according to the vaccine type were 1.07 (95% CI, 0.95-1.21) in the mRNA vaccine subgroup, 0.99 (95% CI, 0.83-1.19) in the ChAdOx1 nCoV-19 vaccine subgroup, and 0.86 (95% CI, 0.68-1.10) in the mix-matched vaccination subgroup. However, in the analysis of individual outcome, the adjusted IRR of myocarditis was increased to 11.71 (95% CI, 5.88-23.35) during the whole risk period. In contrast, no increased risk was observed for other outcomes, such as myocardial infarction, stroke, VTE, and pericarditis.

Conclusion: For cancer patients, COVID-19 vaccination demonstrated an overall safe profile in terms of cardiovascular outcomes. However, caution is required as an increased risk of myocarditis following COVID-19 vaccination was observed in this study.

Background: We performed a nationwide analysis to evaluate the impact of the early coronavirus disease 2019 (COVID-19) pandemic on emergency department (ED) visits by adult cancer patients having COVID-like symptoms.

Methods: We analyzed the National Emergency Department Information System (NEDIS) data on ED visits by adult cancer patients who presented with chief complaints of fever or respiratory symptoms (FRS) indicative of COVID-19, from 2016 to 2020. An interrupted time series analysis with a quasi-Poisson regression model was performed, adjusting for seasonality and time, to evaluate whether underlying trends for monthly ED visits and the in-hospital mortality rate (%) per month changed with the pandemic among these patients. We also estimated the adjusted odds ratio (aOR) of in-hospital deaths among cancer patients using multivariable logistic regression analysis.

Results: ED visits by cancer patients with FRS decreased during the COVID-19 pandemic (relative risk [RR] with 95% confidence interval [CI]: slope change, 0.99 [0.98-1.00] and step change, 0.84 [0.76-0.92]). However, the in-hospital mortality rate (%) for these patients was increased (slope change, 1.14 [1.04-1.25] and step change, 0.99 [0.98-1.01]). Factors such as urgent triage status, ambulance use, and treatment in hospitals with fewer than 300 staffed beds significantly contributed to increased aOR of in-hospital deaths during the COVID-19 pandemic compared to the pre-pandemic period.

Conclusion: Further studies are needed to highlight the importance of ED service preparation in planning and managing resources for cancer patients during future pandemics.

Background: This study compared hearing outcomes with use of personal sound amplification products (PSAPs) and hearing aids (HAs) in patients with moderate to moderately severe unilateral hearing loss.

Methods: Thirty-nine participants were prospectively enrolled, and randomly assigned to use either one HA (basic or premium type) or one PSAP (basic or high-end type) for the first 8 weeks and then the other device for the following 8 weeks. Participants underwent a battery of examinations at three visits, including sound-field audiometry, word recognition score (WRS), speech perception in quiet and in noise, real-ear measurement, and self-report questionnaires.

Results: Functional gain was significantly higher with HAs across all frequencies (P < 0.001). While both PSAPs and HAs improved WRS from the unaided condition, HAs were superior to PSAPs. The speech recognition threshold in quiet conditions and signal-to-noise ratio in noisy conditions were significantly lower in the HA-aided condition than in the PSAP-aided condition, and in the PSAP-aided condition than in the unaided condition. Subjective satisfaction also favored HAs than PSAPs in questionnaires, Abbreviated Profile of Hearing Aid Benefit, International Outcome Inventory for Hearing Aids, and Host Institutional Questionnaire.

Conclusion: While PSAPs provide some benefit for moderate to moderately severe unilateral hearing loss, HAs are more effective. This underscores the potential role of PSAPs as an accessible, affordable first-line intervention in hearing rehabilitation, particularly for individuals facing challenges in accessing conventional HAs.

Background: To analyze the outcomes of clipping and coiling for ruptured intracranial aneurysms (RIAs) based on data from the National Health Insurance Service in South Korea, with a focus on variations according to region and hospital size.

Methods: This study analyzed the one-year mortality rates for patients with RIAs who underwent clipping or coiling in 2018. Coiling was further categorized into non-stent assisted coiling (NSAC) and stent assisted coiling (SAC). Hospitals were classified as tertiary referral general hospitals (TRGHs), general hospitals (GHs), or semi-general hospitals (sGHs) based on size. South Korea's administrative districts were divided into 15 regions for analysis.

Results: In 2018, there were 2,194 (33.1%) clipping procedures (TRGH, 985; GH, 827; sGH, 382) and 4,431 (66.9%) coiling procedures (TRGH, 1,642; GH, 2076; sGH, 713) performed for RIAs treatment. Among hospitals performing more than 20 treatments, the one-year mortality rates following clipping or coiling were 11.2% and 16.0%, respectively, with no significant difference observed. However, there was a significant difference in one-year mortality between NSAC and SAC (14.3% vs. 19.5%, P = 0.034), with clipping also showing significantly lower mortality compared to SAC (P = 0.019). No significant differences in other treatment modalities were observed according to hospital size, but clipping at TRGHs had significantly lower mortality than at GHs (P = 0.042). While no significant correlation was found between the number of treatments and outcomes at GHs, at TRGHs, a higher volume of clipping procedures was significantly associated with lower total mortality (P = 0.023) and mortality after clipping (P = 0.022).

Conclusion: Using Korea NHIS data, mortality rates for RIAs showed no significant variation by hospital size due to coiling's prevalence. However, differences in clipping outcomes by hospital size and volume in TRGH highlight the need for national efforts to improve clipping skills and standardization. Additionally, the higher mortality rate with SAC emphasizes the importance of precise indications for its application.

Heart failure with preserved ejection fraction (HFpEF) is prevalent and associated with a poor prognosis, imposing a significant burden on society. Arterial stiffness is increasingly recognized as a crucial factor in the pathophysiology of HFpEF, affecting diagnosis, management, and prognosis. As a hallmark of vascular aging, arterial stiffness contributes to increased afterload on the left ventricle (LV), leading to diastolic dysfunction, a key feature of HFpEF. Elevated arterial stiffness is linked with common cardiovascular risk factors in HFpEF, such as hypertension, diabetes and obesity, exacerbating the progression of disease. Studies have demonstrated that patients with HFpEF exhibit significantly higher levels of arterial stiffness compared to those without HFpEF, highlighting the value of arterial stiffness measurements as both diagnostic and prognostic tools. Moreover, interventions aimed at reducing arterial stiffness, whether through pharmacological therapies or lifestyle modifications, have shown potential in improving LV diastolic function and patient outcomes. Despite these advancements, the precise mechanisms by which arterial stiffness contributes to HFpEF are still not fully understood, necessitating the need for further research.

Herein, we report a case of uncomplicated falciparum malaria with late parasitological failure in a 45-year-old businessman returning from Ghana. The patient visited the emergency department with high fever, headache, and dizziness. He traveled without antimalarial chemoprophylaxis. Laboratory tests led to the diagnosis of uncomplicated falciparum malaria with an initial density of 37,669 parasites per μL of blood (p/μL). The patient was treated with intravenous artesunate followed by atovaquone/proguanil. He was discharged with improved condition and decreased parasite density of 887 p/μL. However, at follow-up, parasite density increased to 7,630 p/μL despite the absence of any symptoms. Suspecting treatment failure, the patient was administered intravenous artesunate and doxycycline for seven days and then artemether/lumefantrine for three days. Blood smear was negative for asexual parasitemia after re-treatment but positive for gametocytemia until day 101 from the initial diagnosis. Overall, this case highlights the risk of late parasitological failure in patients with imported uncomplicated falciparum malaria.

The recent debate surrounding the expansion of enrollment in Korean medical schools has reignited interest in the Flexner Report, published in the United States in 1910. Historically, medical education in the United States transitioned from small proprietary schools to university-affiliated institutions, emphasizing basic science and clinical experience. The Flexner Report advocated for scientific medicine and led to significant reforms in medical education, including standardization of curricula and strengthened admission requirements. The influence of this report extended to Korean medical education, shaping its curriculum, accreditation system, and emphasis on academic excellence. The expansion of medical school enrollment has led to a crucial dilemma. Should we prioritize the training of physicians who provide practical medical services or continue to emphasize academic medicine as we do now? There has been insufficient discussion of the individualized curricula, necessary investments, and societal efforts to accommodate these changes. It is imperative to move beyond mere enrollment expansion debates and collectively determine the future trajectory of Korean medical education, devising actionable plans to achieve overarching goals.

Background: Multiple myeloma (MM) patients are at risk of skeletal-related events (SREs) like spinal cord compression, pathologic fractures, bone surgery, and radiation to bone. Real-world data regarding SREs in MM are limited.

Methods: We conducted a large, retrospective, nationwide cohort study using the Korean Health Insurance Review and Assessment Service (HIRA) database from 2007 to 2018.

Results: Over a 12-year study period, we identified 6,717 patients who developed symptomatic MM. After a median follow-up of 35.1 months (interquartile range [IQR], 20.8-58.2 months), 43.6% of these patients experienced SREs, and 39.6% had four or more SREs. One in five patients (20.0%) experienced pathologic fractures within the first year of follow-up. The median time to first SRE was 9.6 months (IQR, 1.2-25.8 months), with 3.0 months in the group with prior SREs and 19.8 months in the group without prior SREs. During follow-up, 78.5% of patients received bisphosphonates. Multiple logistic regression analysis revealed several factors associated with an increased risk of SREs, including being female (odds ratio [OR], 1.44), aged 50 or older (OR, 1.87), having cerebrovascular disease (OR, 1.34), undergoing first-line chemotherapy regimens not containing bortezomib or lenalidomide (OR, 1.49), and being in the group with prior SREs and bisphosphonate use (OR, 5.63), compared to the group without prior SREs and without bisphosphonate use.

Conclusion: This population-based study is the first to report the incidence and risk factors of SREs in Korean MM patients, which can be used to assess their bone health.

Background: Malaria elimination strategies in the Republic of Korea (ROK) have decreased malaria incidence but face challenges due to delayed case detection and response. To improve this, machine learning models for predicting malaria, focusing on high-risk areas, have been developed.

Methods: The study targeted the northern region of ROK, near the demilitarized zone, using a 1-km grid to identify areas for prediction. Grid cells without residential buildings were excluded, leaving 8,425 cells. The prediction was based on whether at least one malaria case was reported in each grid cell per month, using spatial data of patient locations. Four algorithms were used: gradient boosted (GBM), generalized linear (GLM), extreme gradient boosted (XGB), and ensemble models, incorporating environmental, sociodemographic, and meteorological data as predictors. The models were trained with data from May to October (2019-2021) and tested with data from May to October 2022. Model performance was evaluated using the area under the receiver operating characteristic curve (AUROC).

Results: The AUROC of the prediction models performed excellently (GBM = 0.9243, GLM = 0.9060, XGB = 0.9180, and ensemble model = 0.9301). Previous malaria risk, population size, and meteorological factors influenced the model most in GBM and XGB.

Conclusion: Machine-learning models with properly preprocessed malaria case data can provide reliable predictions. Additional predictors, such as mosquito density, should be included in future studies to improve the performance of models.