Subarachnoid hemorrhage (SAH) is a stroke subtype with high mortality and poor functional outcomes. Prompt occlusion of a ruptured aneurysm at an early stage is crucial to prevent rebleeding, which can result in even higher mortality and more severe disabilities. The most critical initial decision in SAH management is the choice of treatment method with surgical clipping or endovascular coiling. We aimed to develop an evidence-based clinical guideline to select the optimal initial treatment in patients with SAH. We developed this guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted across four databases (MEDLINE, Embase, Cochrane, and KoreaMed) to answer two population, intervention, comparison, outcome questions comparing clipping and coiling. The risk of bias was assessed using ROB 2.0 and the Newcastle-Ottawa Scale. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagrams and meta-analyses were generated for functional outcome and mortality. We included six randomized control trials (RCTs) and 58 observational studies. Meta-analysis of RCTs showed that coiling improved functional outcomes compared to clipping (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.86–0.97). No significant mortality difference was observed in RCTs (OR, 1.38; 95% CI, 0.91–2.09), but non-RCTs favored clipping for reduced mortality (OR, 0.77; 95% CI, 0.69–0.86). However, it is difficult to generalize these findings to all clinical situations, as patients with SAH have a highly variable clinical course. Final treatment decision should be tailored to the individual patient’s status, including aneurysm location, morphology, and the expertise available at the treatment center. Such decisions are best made by specialists such as a board-certified physician and should be explained to the patient and their caregivers, along with the rationale for selecting the most appropriate treatment at the given hospital. Korea has many certified endovascular neurosurgeons, cerebrovascular surgeons, and certified cerebrovascular centers. Proper selection of the most suitable treatment method by certified physicians and centers would greatly benefit patient outcomes and healthcare professionals.

Accurate and early identification of stroke and large vessel occlusion (LVO) in emergency settings is essential for improving patient outcomes and ensuring the efficient allocation of medical resources. This clinical practice guideline systematically reviews domestic and international literature and conducts meta-analyses to evaluate the utility and diagnostic accuracy of stroke assessment tools used in prehospital emergency medical services (EMS). We developed a guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted to evaluate the usefulness of diagnostic EMS assessment tools for diagnosing stroke and LVO. Overall, 70 non-randomized control studies were selected for this study. A meta-analysis was conducted with a subgroup analysis to distinguish between patients with stroke and those with LVO. EMS tools demonstrated high sensitivity but low specificity for diagnosing stroke. In the prehospital setting, using validated EMS stroke assessment tools is recommended for the early identification of stroke and LVO. Upon hospital arrival, stroke specialists should conduct further evaluation and triage to confirm the diagnosis and guide appropriate management. Delays in diagnosing LVO are frequently unacceptable. While experts advocate for the use of EMS assessment tools to facilitate early identification of LVO, these tools alone lack adequate sensitivity. Therefore, further diagnostic evaluations and consultation with stroke specialists upon hospital arrival are recommended.

The mothership (MS) model, where patients are directly transferred to a thrombectomy-capable center, and the drip-and-ship (DS) model, where thrombolysis is initiated at the nearest primary stroke center before transfer for thrombectomy, are the primary transport modes for patients with stroke. We aimed to establish guidelines for selecting the appropriate transfer strategy based on emergent large vessel occlusion (LVO). We developed this guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted across four databases (MEDLINE, Embase, Cochrane, and KoreaMed) to answer three Population, Intervention, Comparison, and Outcome questions comparing MS and DS models. The risk of bias was assessed using the Newcastle-Ottawa Scale. Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagrams and meta-analyses were generated for functional outcomes, mortality, and successful recanalization. Twenty-six non-randomized controlled studies showed that the MS model improved good functional outcomes by approximately 14% compared with the DS model (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.00–1.30). Fifteen studies reported that mortality in the MS and DS models showed no significant differences (OR, 0.97; 95% CI, 0.84–1.11). Twenty-four studies revealed no significant difference in successful recanalization between the MS and DS models (OR, 0.87; 95% CI, 0.68–1.10). The MS model should be considered first to improve the functional outcome of patients with LVO. However, if thrombectomy cannot be performed immediately after thrombolysis, or if a thrombectomy-enabled hospital is not nearby, the DS model should be considered by stroke specialists depending on transportation time and regional factors. We suggest a mixed approach with the DS model based on specific circumstances or regions to ensure the optimum treatment of patients with acute ischemic stroke (AIS). Appropriate transport for patients with LVO improves the prognosis of AIS.

Background: To identify a screening tool for obstructive sleep apnea (OSA) and evaluate the effects of endoscopic transsphenoidal surgery on improving OSA in patients with acromegaly. Methods: We prospectively enrolled adults with acromegaly scheduled for endoscopic transsphenoidal surgery. All measurements were conducted when participants were admitted for a baseline work-up for acromegaly before surgery and surveillance approximately 3 to 6 months after surgery. Respiratory event index (REI) was used as a surrogate for apnea-hypopnea index (Trial Registration: NCT03526016). Results: Of the 35 patients with acromegaly (median age, 47 years; 40% men; median body mass index, 24.4 kg/m2), 24 (68.6%) had OSA (REI ≥5/hour), 15 (42.9%) had moderate-to-severe OSA (REI ≥15/hour). At baseline, serum insulin-like growth factor 1 (IGF-1) levels were positively correlated with the REI (ρ=0.53, P=0.001). The sensitivity and negative predictive value of a Snoring, Tiredness, Observed apnea, high blood Pressure-Body mass index, age, Neck circumference, and Gender (STOP-Bang) score ≥ 3 were 93.3% and 87.5%, respectively, detecting moderate-to-severe OSA. Biochemical acromegaly remission was achieved in 32 (91.4%) patients. The median difference in the REI was –9.5/hour (95% confidence interval, –13.3 to –5.3). Half of the 24 patients diagnosed with OSA preoperatively had REI <5/hour postoperatively. In a linear mixed-effects model, changes in the REI across surgery were related to changes in IGF-1 levels. Conclusion The STOP-Bang questionnaire is a reliable tool for OSA among patients with acromegaly. Improvement in OSA severity after surgery is related to decreased IGF-1 levels.

Background/Aims: The prevalence and effects of airway diseases, including asthma, eosinophilic bronchitis (EB), chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap (ACO) have not been thoroughly studied in patients with idiopathic pulmonary fibrosis (IPF). This study aimed to evaluate the prevalence of airway diseases in patients with IPF and to identify the differences in symptoms based on the presence of airway diseases. Methods: This single-institution prospective cohort study was conducted from June 2017 to September 2018, at the Seoul National University Hospital. Spirometry with bronchodilator, methacholine bronchial provocation test, induced sputum with eosinophil stain, and exhaled nitric oxide were performed to confirm the presence of airway disease. The modified Medical Research Council (mMRC) dyspnea scale, COPD assessment test (CAT), St. George’s Respiratory Questionnaire (SGRQ), EuroQol-5 dimension (EQ-5D) index, and cough-specific quality of life questionnaire (CQLQ) data were collected to assess symptom severity. Results: Total 147 patients with IPF were screened, and 70 patients were analyzed. The prevalence of airway diseases in the participants was as follows: 5.0% had COPD, 1.7% had asthma, 3.3% had ACO, and 1.7% had EB. The mMRC, CAT, SGRQ, EQ-5D, and CQLQ scores did not differ regardless of combined airway disease. After 3 months, the SGRQ (p = 0.028) and CQLQ (p = 0.030) scores were significantly higher in patients with airway disease than in those without. Conclusions The prevalence of airway diseases in patients with IPF is low, but when airway diseases are accompanied by IPF, symptom severity and quality of life may worsen rapidly.

Background/Aims: There are concerns that the use of renin-angiotensin system (RAS) blockers may increase the risk of being infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or progressing to a severe clinical course after infection. This this study aimed to investigate the influence of RAS blockers on the risk and severity of SARS-CoV-2 infection. Methods: We conducted a retrospective cohort study analyzing nationwide claims data of 215,184 adults who underwent SARS-CoV-2 tests in South Korea. The SARS-CoV-2 positive rates and clinical outcomes were evaluated according to the use of RAS blockers in patients with hypertension (n = 64,243). Results: In total, 38,919 patients with hypertension were on RAS blockers. The SARS-CoV-2 positive rates were significantly higher in the RAS blocker group than in the control group after adjustments (adjusted odds ratio [OR], 1.22; 95% confidence interval [CI], 1.10 to 1.36; p < 0.001), and matching by propensity score (adjusted OR, 1.16; 95% CI, 1.03 to 1.32; p = 0.017). Among the 1,609 SARS-CoV-2-positive patients with hypertension, the use of RAS blockers was not associated with poor outcomes, such as mortality (adjusted OR, 0.81; 95% CI, 0.56 to 1.17; p = 0.265), and a composite of admission to the intensive care unit and mortality (adjusted OR, 0.95; 95% CI, 0.73 to 1.22; p = 0.669). Analysis in the propensity scorematched population showed consistent results. Conclusions In this Korean nationwide claims dataset, the use of RAS blockers was associated with a higher risk to SARS-CoV-2 infection but not with higher mortality or other severe clinical courses.

Objective: With trends in population aging an increasing number of older patients are visiting the emergency department (ED). This study aimed to identify the characteristics of ED utilization and risk factors for in-hospital mortality in older patients who visited EDs. Methods: This nationwide observational study used National Emergency Department Information System data collected during a 2-year period from January 2016 to December 2017. The characteristics of older patients aged 70 years or older were compared with those of younger patients aged 20 to 69 years. Risk factors associated with in-hospital mortality were analyzed by multivariable logistic regression. Results: A total of 6,596,423 younger patients and 1,737,799 older patients were included. In the medical and nonmedical older patient groups, significantly higher proportions of patients were transferred from another hospital, utilized emergency medical services, had Korean Triage and Acuity Scale scores of 1 and 2, required hospitalization, and required intensive care unit admission in the older patient group than in the younger patient group. ED and post-hospitalization mortality rates increased with age; in particular, older medical patients aged 90 or older had an in-hospital mortality rate of 9%. Older age, male sex, transfer from another hospital, emergency medical service utilization, a high Korean Triage and Acuity Scale score, systolic blood pressure <100 mmHg, respiratory rate >20/min, heart rate >100/min, body temperature <36°C, and altered mental status were associated with in-hospital mortality. Conclusion Development of appropriate decision-making algorithms and treatment protocols for high risk older patients visiting the ED might facilitate appropriate allocation of medical resources to optimize outcomes.

Background: The prevalence of congenital anomalies in newborns in South Korea was 272.9 per 100,000 in 2005, and 314.7 per 100,000 in 2006. In other studies, the prevalence of congenital anomalies in South Korea was equivalent to 286.9 per 10,000 livebirths in 2006, while it was estimated 446.3 per 10,000 births during the period from 2008 to 2014. Several systematic reviews and meta-analyses analyzing the factors contributing to congenital anomalies have been reported, but comprehensive umbrella reviews are lacking. Methods: We searched PubMed, Google Scholar, Cochrane, and EMBASE databases up to July 1, 2019, for systematic reviews and meta-analyses that investigated the effects of environmental and genetic factors on any type of congenital anomalies. We categorized 8 subgroups of congenital anomalies classified according to the 10th revision of the International Statistical Classification of Diseases (ICD-10). Two researchers independently searched the literature, retrieved the data, and evaluated the quality of each study. Results: We reviewed 66 systematic reviews and meta-analyses that investigated the association between non-genetic or genetic risk factors and congenital anomalies. Overall, 269 associations and 128 associations were considered for environmental and genetic risk factors, respectively. Congenital anomalies based on congenital heart diseases, cleft lip and palate, and others were associated with environmental risk factors based on maternal exposure to environmental exposures (air pollution, toxic chemicals), parental smoking, maternal history (infectious diseases during pregnancy, pregestational and gestational diabetes mellitus, and gestational diabetes mellitus), maternal obesity, maternal drug intake, pregnancy through artificial reproductive technologies, and socioeconomic factors. The association of maternal alcohol or coffee consumption with congenital anomalies was not significant, and maternal folic acid supplementation had a preventive effect on congenital heart defects. Genes or genetic loci associated with congenital anomalies included MTHFR, MTRR and MTR, GATA4, NKX2-5, SRD5A2, CFTR, and 1p22 and 20q12 anomalies. Conclusion This study provides a wide perspective on the distribution of environmental and genetic risk factors of congenital anomalies, thus suggesting future studies and providing health policy implications.

Background: The prevalence of congenital anomalies in newborns in South Korea was 272.9 per 100,000 in 2005, and 314.7 per 100,000 in 2006. In other studies, the prevalence of congenital anomalies in South Korea was equivalent to 286.9 per 10,000 livebirths in 2006, while it was estimated 446.3 per 10,000 births during the period from 2008 to 2014. Several systematic reviews and meta-analyses analyzing the factors contributing to congenital anomalies have been reported, but comprehensive umbrella reviews are lacking. Methods: We searched PubMed, Google Scholar, Cochrane, and EMBASE databases up to July 1, 2019, for systematic reviews and meta-analyses that investigated the effects of environmental and genetic factors on any type of congenital anomalies. We categorized 8 subgroups of congenital anomalies classified according to the 10th revision of the International Statistical Classification of Diseases (ICD-10). Two researchers independently searched the literature, retrieved the data, and evaluated the quality of each study. Results: We reviewed 66 systematic reviews and meta-analyses that investigated the association between non-genetic or genetic risk factors and congenital anomalies. Overall, 269 associations and 128 associations were considered for environmental and genetic risk factors, respectively. Congenital anomalies based on congenital heart diseases, cleft lip and palate, and others were associated with environmental risk factors based on maternal exposure to environmental exposures (air pollution, toxic chemicals), parental smoking, maternal history (infectious diseases during pregnancy, pregestational and gestational diabetes mellitus, and gestational diabetes mellitus), maternal obesity, maternal drug intake, pregnancy through artificial reproductive technologies, and socioeconomic factors. The association of maternal alcohol or coffee consumption with congenital anomalies was not significant, and maternal folic acid supplementation had a preventive effect on congenital heart defects. Genes or genetic loci associated with congenital anomalies included MTHFR, MTRR and MTR, GATA4, NKX2-5, SRD5A2, CFTR, and 1p22 and 20q12 anomalies. Conclusion This study provides a wide perspective on the distribution of environmental and genetic risk factors of congenital anomalies, thus suggesting future studies and providing health policy implications.

Objective: With trends in population aging an increasing number of older patients are visiting the emergency department (ED). This study aimed to identify the characteristics of ED utilization and risk factors for in-hospital mortality in older patients who visited EDs. Methods: This nationwide observational study used National Emergency Department Information System data collected during a 2-year period from January 2016 to December 2017. The characteristics of older patients aged 70 years or older were compared with those of younger patients aged 20 to 69 years. Risk factors associated with in-hospital mortality were analyzed by multivariable logistic regression. Results: A total of 6,596,423 younger patients and 1,737,799 older patients were included. In the medical and nonmedical older patient groups, significantly higher proportions of patients were transferred from another hospital, utilized emergency medical services, had Korean Triage and Acuity Scale scores of 1 and 2, required hospitalization, and required intensive care unit admission in the older patient group than in the younger patient group. ED and post-hospitalization mortality rates increased with age; in particular, older medical patients aged 90 or older had an in-hospital mortality rate of 9%. Older age, male sex, transfer from another hospital, emergency medical service utilization, a high Korean Triage and Acuity Scale score, systolic blood pressure <100 mmHg, respiratory rate >20/min, heart rate >100/min, body temperature <36°C, and altered mental status were associated with in-hospital mortality. Conclusion Development of appropriate decision-making algorithms and treatment protocols for high risk older patients visiting the ED might facilitate appropriate allocation of medical resources to optimize outcomes.