Perioperative adverse cardiac events and mortality after non-cardiac surgery: a multicenter study / 대한마취과학회지

Background@#Perioperative adverse cardiac events (PACE), a composite of myocardial infarction, coronary revascularization, congestive heart failure, arrhythmic attack, acute pulmonary embolism, cardiac arrest, and stroke during 30-day postoperative period, is associated with long-term mortality, but with limited clinical evidence. We compared long-term mortality with PACE using data from nationwide multicenter electronic health records. @*Methods@#Data from 7 hospitals, converted to Observational Medical Outcomes Partnership Common Data Model, were used. We extracted records of 277,787 adult patients over 18 years old undergoing non-cardiac surgery for the first time at the hospital and had medical records for more than 180 days before surgery. We performed propensity score matching and then an aggregated meta‑analysis. @*Results@#After 1:4 propensity score matching, 7,970 patients with PACE and 28,807 patients without PACE were matched. The meta‑analysis showed that PACE was associated with higher one-year mortality risk (hazard ratio [HR]: 1.33, 95% CI [1.10, 1.60], P = 0.005) and higher three-year mortality (HR: 1.18, 95% CI [1.01, 1.38], P = 0.038). In subgroup analysis, the risk of one-year mortality by PACE became greater with higher-risk surgical procedures (HR: 1.20, 95% CI [1.04, 1.39], P = 0.020 for low-risk surgery; HR: 1.69, 95% CI [1.45, 1.96], P < 0.001 for intermediate-risk; and HR: 2.38, 95% CI [1.47, 3.86], P = 0.034 for high-risk). @*Conclusions@#A nationwide multicenter study showed that PACE was significantly associated with increased one-year mortality. This association was stronger in high-risk surgery, older, male, and chronic kidney disease subgroups. Further studies to improve mortality associated with PACE are needed.

Clinical Characteristics of Psoriasis for Initiation of Biologic Therapy: A Cluster Analysis

Background@#Psoriasis is a complex and heterogeneous disease that widely affects a patient’s life. Biological therapy is usually prescribed in patients with severe psoriasis that do not respond to conventional treatment. However, data on the specific patient characteristics receiving biologics are still unavailable. @*Objective@#To classify patients with psoriasis into subgroups with distinct phenotypes through cluster analysis, and to evaluate the differences between the clusters to predict disease prognosis by examining the response to biological therapy. @*Methods@#The clinical characteristics of the patients with psoriasis were investigated and categorized using hierarchical cluster analysis. After clustering, the clinical characteristics of the patients were compared and the initiation of treatment with biologics according to the clusters were evaluated. @*Results@#A total of 361 patients with psoriasis were classified into two clusters using 16 distinct clinical phenotypes. Group 1 (n=202) consisted of male smokers and alcohol users with higher psoriasis area and severity index (PASI), older age of onset, higher body mass index, and comorbidities including psoriatic arthritis, hypertension, and diabetes when compared to group 2 (n=159). Group 1 had a significantly higher probability of biological treatment initiation than group 2 (p=0.039). The measured risk factors for the initiation of biologics compared were PASI (p<0.001) and nail involvement (p=0.022). @*Conclusion@#Cluster analysis classified patients with psoriasis into two subgroups according to their clinical characteristics. Predicting the disease prognosis using a combination of specific clinical parameters may aid in the management of the disease.

Machine Learning-assisted Quantitative Mapping of Intracortical Axonal Plasticity Following a Focal Cortical Stroke in Rodents

Stroke destroys neurons and their connections leading to focal neurological deficits. Although limited, many patients exhibit a certain degree of spontaneous functional recovery. Structural remodeling of the intracortical axonal connections is implicated in the reorganization of cortical motor representation maps, which is considered to be an underlying mechanism of the improvement in motor function. Therefore, an accurate assessment of intracortical axonal plasticity would be necessary to develop strategies to facilitate functional recovery following a stroke. The present study developed a machine learning-assisted image analysis tool based on multi-voxel pattern analysis in fMRI imaging. Intracortical axons originating from the rostral forelimb area (RFA) were anterogradely traced using biotinylated dextran amine (BDA) following a photothrombotic stroke in the mouse motor cortex. BDA-traced axons were visualized in tangentially sectioned cortical tissues, digitally marked, and converted to pixelated axon density maps. Application of the machine learning algorithm enabled sensitive comparison of the quantitative differences and the precise spatial mapping of the post-stroke axonal reorganization even in the regions with dense axonal projections. Using this method, we observed a substantial extent of the axonal sprouting from the RFA to the premotor cortex and the peri-infarct region caudal to the RFA. Therefore, the machine learningassisted quantitative axonal mapping developed in this study can be utilized to discover intracortical axonal plasticity that may mediate functional restoration following stroke.

Discordance in Secular Trends of Bone Mineral Density Measurements in Different Ages of Postmenopausal Women

Background@#Age-adjusted bone mineral density (BMD) in postmenopausal women decreases in developed countries whereas incidence of osteoporotic fracture decreases or remains stable. We investigated secular trends of bone density from 2008 to 2017 among different age groups of postmenopausal women. @*Methods@#We analyzed BMD data obtained from health check-ups of 4,905 postmenopausal women during three survey cycles from 2008 to 2017. We divided them into 3 groups by age (50–59 years, 60–69 years, and 70 years or more) and observed the transition of lumbar and femoral BMD in each group, before and after adjusting for variables that may affect BMD. @*Results@#Age-adjusted BMD, bone mineral content (BMC), and T-score demonstrated a declining trend over the survey period at lumbar spine (−2.8%), femur neck (−3.5%) and total femur (−4.3%), respectively. In the analysis for the age groups, the BMD, BMC, and T-score presented linear declining trend (−6.1%) in younger postmenopausal women while women aged over 70 or more showed linear increasing trends (+6.3%) at lumbar spine during the survey period. Femoral neck and total femur BMD demonstrated a declining linear trend only in the 50–59 and 60–69 years groups (−5.5%, −5.2%, respectively), but not in the 70 years or more group. @*Conclusion@#BMD in younger postmenopausal women has decreased considerably but has increased or plateaued in elderly women. This discordance of BMD trends among different age groups may contribute to decreased incidence of osteoporotic fracture despite a recent declining BMD trend in postmenopausal women.

Intramuscular Injection of Autologous Serum in Adolescent and Adult Patients with Atopic Dermatitis: A Preliminary Randomized Clinical Trial

Purpose@#The favorable clinical efficacies of intramuscular injection of autologous blood in patients with atopic dermatitis (AD) and intramuscular injection of autologous serum in patients with chronic urticaria have been demonstrated by randomized clinical trials. In this study, we assessed the clinical effectiveness and safety of the intramuscular injection of autologous serum in patients with AD. @*Materials and Methods@#In this randomized, placebo-controlled, and double-blind trial, 23 adolescent and adult patients with moderate-to-severe AD were enrolled. The patients were randomized to receive eight intramuscular injections of 5 mL of autologous serum (n=11) or saline (n=12) over 4 weeks, and were followed up until week 8. Changes in the clinical severity scores of AD assessed by SCORing Atopic Dermatitis (SCORAD), patient-reported Dermatology Life Quality Index (DLQI) score, and incidence of adverse events were assessed from baseline to week 8. @*Results@#One patient in the treatment group and two patients in the placebo group were lost to follow-up before week 8. The intramuscular administration of autologous serum, compared with saline, decreased the SCORAD clinical severity score (-14.8% vs. 10.7%, p=0.006) and improved the DLQI score (-32.6% vs. 19.5%, p=0.01) from baseline to week 8. Serious adverse events were not observed. @*Conclusion@#Intramuscular injection of autologous serum may be effective in treating AD. Further studies are needed to evaluate the clinical usefulness of this intervention for AD (KCT0001969).

Antibody response to COVID-19vaccination in patients on chronic hemodialysis

Purpose@#Since patients on hemodialysis (HD) are known to be vulnerable to coronavirus disease 2019 (COVID-19), many studies were conducted regarding the effectiveness of the COVID-19 vaccine in HD patients in Western countries. Here, we assessed antibody response of HD patients for 6 months post-vaccination to identify the duration and effectiveness of the COVID-19 vaccine in the Asian population. @*Materials and Methods@#We compared antibody response of the COVID-19 vaccine in HD patients with healthy volunteers. Patient and control groups had two doses of ChAdOx1 nCoV-19 and mRNA-1273, respectively. Immunoglobulin G (IgG) was measured before vaccination, 2 weeks after the first dose, 2 and 4 weeks, 3 and 6 months after the second dose. Neutralizing antibody was measured before vaccination and at 2 weeks, 3 and 6 months after second dose.Since the third dose was started in the middle of the study, we analyzed the effect of the third dose as well. @*Results@#Although antibody production was weaker than the control group (n=22), the patient group (n=39) showed an increase in IgG and neutralizing antibody after two doses. And, 21/39 patients and 14/22 participants had a third dose (BNT162b2 or mRNA-1273 in the patient group, mRNA-1273 in the control group), and it did not affect antibody response in both group. Trend analysis showed IgG and neutralizing antibody did not decrease over time. Age, sex, and HD vintage did not affect antibody production in HD patients. Patients with higher body mass index displayed better seroresponse, while those on immunosuppressants showed poor seroresponse. @*Conclusion@#Two doses of vaccination led to significant antibody response in HD patients, and the antibody did not wane until 6 months.

Principal Component Analysis to Differentiate Patients with Palmoplantar Pustulosis from Those with Palmoplantar Pustular Psoriasis

Background@#Palmoplantar pustulosis (PPP) is initiated from the acrosyringium. However, it is unclear whether PPP should be considered a distinct entity or should be classified into the spectrum of pustular psoriasis, also known as palmoplantar pustular psoriasis (PPPP). @*Objective@#We evaluated the differences in immunohistochemical staining in patients with PPP to determine whether they can be classified into two groups based on psoriatic properties or acrosyringeal properties. @*Methods@#Nineteen punch biopsy specimens diagnosed with PPP were collected. Antibodies were chosen for identifying the acrosyringeal properties of α-3-nicotine acetylcholine receptors (α-3-nAChR), psoriatic properties of interleukin (IL)-23 and IL-36R, inflammatory cell properties of human cathelicidin antimicrobial peptide 18/LL-37, IL-8, lipocalin-2 (LCN2), and CD3. The degree of staining of the epidermis was evaluated using the ordinal scale (0~3). The principal component analysis was used to derive principal components (PCs) of common variation between the stains, and the two groups were divided using PCs and cluster analysis. @*Results@#Three main PCs explained 64% of the total variance in PPP. PC1 (pustular psoriasis properties) showed a higher correlation with IL-36R. PC2 (acrosyringeal/inflammatory properties) showed a higher correlation with α-3-nAChR, IL-8, LCN2, and CD3. PC3 (psoriasis properties) showed a higher correlation with IL-23. PC1 showed a statistically significant difference (p=0.0284) between the two groups. We identified three PCs associated with the pathomechanisms of PPP. @*Conclusion@#Although PC1 showed a statistically significant difference between the two groups, we did not identify differential protein expression related to the pathogenesis between PPP and PPPP.

Mental illness in patients with end-stage kidney disease in South Korea: a nationwide cohort study

The limited literature on mental illness in end-stage kidney disease (ESKD) patients suggests that this disease is common and burdensome but underrecognized in clinical practice. This study aimed to analyze the prevalence of mental illness in ESKD patients. Methods: We assessed the prevalence and patterns of mental illnesses in a nationwide cohort of patients diagnosed with ESKD between January 1, 2008, and December 31, 2017. The risk of mental illness was evaluated using a multivariable Cox proportional hazards model. Results: A total of 70,079 patients met all study inclusion criteria. A total of 28.3% of patients had mental illness, and the specific distribution was as follows: depression, 16.8%; anxiety, 20.0%; somatoform/conversion disorder, 0.9%; stress reaction/adjustment disorder, 2.5%; and substance abuse disorder, 0.6%. The frequency of mental illness was highest in patients on hemodialysis (HD), followed by patients on peritoneal dialysis (PD) and kidney transplant (KT) patients. The peak rate of mental illness in HD and PD patients was reached 1 to 2 years after renal replacement therapy initiation, but the peak rate of most mental illnesses in KT patients occurred before surgery. The prevalence of depression was 2.19 times higher in HD patients and 1.97 times higher in PD patients than in KT patients. Conclusion: ESKD patients are at high risk of mental illness, and the prevalence of mental illness is highest in HD patients. Since the onset of mental illness occurs around the initiation of renal replacement therapy, clinicians need to pay attention to mental illness when treating ESKD patients.

Baseline Clinical and Biomarker Characteristics of Biobank Innovations for Chronic Cerebrovascular Disease With Alzheimer’s Disease Study: BICWALZS

Objective@#We aimed to present the study design and baseline cross-sectional participant characteristics of biobank innovations for chronic cerebrovascular disease with Alzheimer’s disease study (BICWALZS) participants. @*Methods@#A total of 1,013 participants were enrolled in BICWALZS from October 2016 to December 2020. All participants underwent clinical assessments, basic blood tests, and standardized neuropsychological tests (n=1,013). We performed brain magnetic resonance imaging (MRI, n=817), brain amyloid positron emission tomography (PET, n=713), single nucleotide polymorphism microarray chip (K-Chip, n=949), locomotor activity assessment (actigraphy, n=200), and patient-derived dermal fibroblast sampling (n=175) on a subset of participants. @*Results@#The mean age was 72.8 years, and 658 (65.0%) were females. Based on clinical assessments, total of 168, 534, 211, 80, and 20 had subjective cognitive decline, mild cognitive impairment (MCI), Alzheimer’s dementia, vascular dementia, and other types of dementia or not otherwise specified, respectively. Based on neuroimaging biomarkers and cognition, 199, 159, 78, and 204 were cognitively normal (CN), Alzheimer’s disease (AD)-related cognitive impairment, vascular cognitive impairment, and not otherwise specified due to mixed pathology (NOS). Each group exhibited many differences in various clinical, neuropsychological, and neuroimaging results at baseline. Baseline characteristics of BICWALZS participants in the MCI, AD, and vascular dementia groups were generally acceptable and consistent with 26 worldwide dementia cohorts and another independent AD cohort in Korea. @*Conclusion@#The BICWALZS is a prospective and longitudinal study assessing various clinical and biomarker characteristics in older adults with cognitive complaints. Details of the recruitment process, methodology, and baseline assessment results are described in this paper.

Cancer risk in Korean patients with gout

Background/Aims@#Using a nationwide cohort, we investigated the cancer risk in Korean patients with gout. @*Methods@#Data were obtained from the Korean National Health Insurance Service Database. Patients with gout were defined as those aged ≥ 20 years who were diagnosed with gout and received anti-gout medication (allopurinol, colchicine, and benzbromarone) between 2008 and 2010. Patients with nail disorders were randomly assigned to a control group (1:1 ratio) after frequency matching for age and sex. Cancer incidence was then investigated between 2012 and 2018. Cox proportional hazard regression analysis was used to investigate the association between gout and cancer after adjusting for concomitant diseases. @*Results@#This study included 179,930 patients with gout and an equal number of matched controls. The incidence of overall cancer was higher in patients with gout than in controls (incidence rate ratio, 1.08). Cox proportional hazards regression analysis showed that gout was associated with a hazard ratio of 1.053 (95% confidence interval ,1.031 to 1.077) after adjusting for concomitant diseases. @*Conclusions@#Gout was associated with a significantly high risk of cancer, especially esophageal, stomach, colon, liver, pancreatic, lung, ovarian, renal, and bladder cancers.

Independent Risk Factors for Hepatocellular Carcinoma Recurrence after Direct-Acting Antiviral Therapy in Patients with Chronic Hepatitis C

Background/Aims@#This study was performed to evaluate the efficacy of direct-acting antivirals (DAAs) in Korean patients with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) and to investigate the risk factors associated with HCC recurrence. @*Methods@#A total of 100 patients with HCV-related HCC, who were treated with DAAs between May 2015 and December 2016, were recruited from seven university hospitals in Korea. Claim data of 526 patients with HCC obtained from the Health Insurance Review and Assessment Service in South Korea were used for external validation of the results. @*Results@#Among the 100 patients, 88% achieved a sustained virological response (SVR) 12weeks after the end of DAA therapy (SVR12), and 37% experienced HCC recurrence after DAA therapy. Short last HCC treatment durability (<12 months) before DAA commencement was independently associated with HCC recurrence (hazard ratio [HR], 2.89; p=0.011). In the nationwide validation cohort, 20.3% of the patients experienced HCC recurrence. The last HCC treatment with a noncurative method, a short last HCC treatment durability (<12 months), and a longer total duration of HCC treatment (≥18 months) were independently related with HCC recurrence (HR3.73, p<0.001; HR 3.34, p<0.001; and HR 1.74, p=0.006; respectively). @*Conclusions@#DAA therapy showed an acceptable SVR12 rate in patients with HCV-related HCC. Short last HCC treatment durability (<12 months) was associated with HCC recurrence after DAA therapy. This finding suggests that the last HCC treatment durability is an important predictor of HCC recurrence after DAA therapy.

Association Between Suicide Risk and Comorbidity of Mood Disorder and Alcohol Use Disorder:Using Common Data Model in Psychiatry / 신경정신의학

Objectives@#This study determines the effects of comorbidity of mood disorder and alcohol use disorder on suicide behavior. @*Methods@#We converted data from the electronic medical records of one university hospital into a common data model and utilized it in our analysis. We selected 9551 patients with diagnosis codes of mood disorders or alcohol use disorders and divided them into three groups: mood disorder (MD) only, alcohol use disorder (AUD) only, and comorbidity of mood disorder and alcohol use disorder (MD+AUD). The mood disorder group was also subgrouped with depressive (DD) or bipolar affective disorder (BD) groups, and the comorbidity group was classified in the same way. Then, we applied logistic regression analysis to assess the risk of suicide attempts between the diagnostic groups. Subgroup analysis according to age also was conducted. @*Results@#The MD+AUD group had 2.7 (odd ratio [OR]=2.70, 95% confidence intervals [CI]=1.91– 3.81, p<0.0001) and the DD+AUD group had 2.78 (OR=2.78, 95% CI=1.95–3.98, p<0.0001) times higher risk of suicide attempts than the MD only and DD only group, respectively. Furthermore, according to the age subgroup, the risk of suicide attempts was the highest (OR=5.17, 95% CI=2.35–11.40, p<0.0001) in the DD+AUD group for those aged 40–59. There were no significant results in BD. @*Conclusion@#The results showed that the comorbidity of mood disorder and alcohol use disorder could increase suicide risk. This study suggested that alcohol use behavior needs to be assessed as well as mood symptoms for suicide prevention.

Effects of Oxygen Saturation Fluctuations on Retinopathy in Infants Younger than 30 Weeks’ Gestational Age

Purpose@#To evaluate the risk factors and effects of fluctuations in oxygen saturation on the occurrence and severity of retinopathy of prematurity (ROP). @*Methods@#From January 1, 2013 to January 31, 2020, 260 patients hospitalized in the neonatal intensive care unit of Ajou University Hospital were retrospectively analyzed. @*Results@#Sixty-six patients (25%) were diagnosed with ROP; of them 39 required treatment. In the multivariate regression analysis of ROP severity, the odds ratio (OR) of gestational age was 0.32 (95% confidence interval [CI], 0.22 to 0.47; P<0.0001). The OR of saturation of peripheral oxygen (SpO2) fluctuations at the 4th week after birth was 1.02 (95% CI, 1.02 to 1.12; P=0.041). @*Conclusion@#SpO2 fluctuations in premature infants younger than 30 weeks’ gestational age affects ROP severity, especially at the 4th week of life.

Independent Risk Factors for Hepatocellular Carcinoma Recurrence after Direct-Acting Antiviral Therapy in Patients with Chronic Hepatitis C

Background/Aims@#This study was performed to evaluate the efficacy of direct-acting antivirals (DAAs) in Korean patients with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) and to investigate the risk factors associated with HCC recurrence. @*Methods@#A total of 100 patients with HCV-related HCC, who were treated with DAAs between May 2015 and December 2016, were recruited from seven university hospitals in Korea. Claim data of 526 patients with HCC obtained from the Health Insurance Review and Assessment Service in South Korea were used for external validation of the results. @*Results@#Among the 100 patients, 88% achieved a sustained virological response (SVR) 12weeks after the end of DAA therapy (SVR12), and 37% experienced HCC recurrence after DAA therapy. Short last HCC treatment durability (<12 months) before DAA commencement was independently associated with HCC recurrence (hazard ratio [HR], 2.89; p=0.011). In the nationwide validation cohort, 20.3% of the patients experienced HCC recurrence. The last HCC treatment with a noncurative method, a short last HCC treatment durability (<12 months), and a longer total duration of HCC treatment (≥18 months) were independently related with HCC recurrence (HR3.73, p<0.001; HR 3.34, p<0.001; and HR 1.74, p=0.006; respectively). @*Conclusions@#DAA therapy showed an acceptable SVR12 rate in patients with HCV-related HCC. Short last HCC treatment durability (<12 months) was associated with HCC recurrence after DAA therapy. This finding suggests that the last HCC treatment durability is an important predictor of HCC recurrence after DAA therapy.

Association Between Suicide Risk and Comorbidity of Mood Disorder and Alcohol Use Disorder:Using Common Data Model in Psychiatry / 신경정신의학

Objectives@#This study determines the effects of comorbidity of mood disorder and alcohol use disorder on suicide behavior. @*Methods@#We converted data from the electronic medical records of one university hospital into a common data model and utilized it in our analysis. We selected 9551 patients with diagnosis codes of mood disorders or alcohol use disorders and divided them into three groups: mood disorder (MD) only, alcohol use disorder (AUD) only, and comorbidity of mood disorder and alcohol use disorder (MD+AUD). The mood disorder group was also subgrouped with depressive (DD) or bipolar affective disorder (BD) groups, and the comorbidity group was classified in the same way. Then, we applied logistic regression analysis to assess the risk of suicide attempts between the diagnostic groups. Subgroup analysis according to age also was conducted. @*Results@#The MD+AUD group had 2.7 (odd ratio [OR]=2.70, 95% confidence intervals [CI]=1.91– 3.81, p<0.0001) and the DD+AUD group had 2.78 (OR=2.78, 95% CI=1.95–3.98, p<0.0001) times higher risk of suicide attempts than the MD only and DD only group, respectively. Furthermore, according to the age subgroup, the risk of suicide attempts was the highest (OR=5.17, 95% CI=2.35–11.40, p<0.0001) in the DD+AUD group for those aged 40–59. There were no significant results in BD. @*Conclusion@#The results showed that the comorbidity of mood disorder and alcohol use disorder could increase suicide risk. This study suggested that alcohol use behavior needs to be assessed as well as mood symptoms for suicide prevention.

A Study on the Clinicopathological Characteristics Associated with Cervical Lymph Mode Metastasis and Extra-nodal Extension in Patients with Oral Cancer / 대한두경부종양학회지

Background/Objectives@#Extra-nodal extension (ENE) is one of the strongest prognosticators in oral cancers. Here we tried to evaluate clinicopathological factors associated with the presence of ENE.Materials & Methods: We retrospectively analyzed clinical information of 120 patients who diagnosed with oral cancer and received curative surgery at our hospital from Mar 2012 to Apr 2020. We comparatively analyzed clinicopathological factors associated with the presence of lymph node (LN) metastasis and ENE, respectively. @*Results@#Variable factors of primary tumor characteristics such as lymphovascular invasion, perineural invasion, largest diameter of tumor, depth of invasion and maximum standardized uptake value were significantly associated with the presence of cervical LN metastasis. The largest diameter of tumor was statistically significant also in multivariate analysis for predicting the LN metastasis. Meanwhile, the association between primary tumor characteristics and the presence of ENE were not statistically significant except the primary tumor size. Importantly, factors associated with LN characteristics including the maximum diameter and number of metastatic LNs were significantly associated with ENE. @*Conclusion@#In this study, several factors affecting cervical LN metastasis and ENE in oral cancer patients were identified. The ENE seems to be influenced by the status of the metastatic LNs, such as the number of metastatic LNs, rather than the characteristics of the primary tumor itself.

Effects of Oxygen Saturation Fluctuations on Retinopathy in Infants Younger than 30 Weeks’ Gestational Age

Purpose@#To evaluate the risk factors and effects of fluctuations in oxygen saturation on the occurrence and severity of retinopathy of prematurity (ROP). @*Methods@#From January 1, 2013 to January 31, 2020, 260 patients hospitalized in the neonatal intensive care unit of Ajou University Hospital were retrospectively analyzed. @*Results@#Sixty-six patients (25%) were diagnosed with ROP; of them 39 required treatment. In the multivariate regression analysis of ROP severity, the odds ratio (OR) of gestational age was 0.32 (95% confidence interval [CI], 0.22 to 0.47; P<0.0001). The OR of saturation of peripheral oxygen (SpO2) fluctuations at the 4th week after birth was 1.02 (95% CI, 1.02 to 1.12; P=0.041). @*Conclusion@#SpO2 fluctuations in premature infants younger than 30 weeks’ gestational age affects ROP severity, especially at the 4th week of life.

Clinical and Laboratory Findings of Barley Allergy in Korean Children: a Single Hospital Based Retrospective Study

BACKGROUND@#Barley is a grain that is consumed in various forms in Asia. Studies on barley allergy are limited to a few case reports about hypersensitivity reactions to beer, but there is no barley allergy study in children. This study aimed to identify the phenotype and immunologic findings in Korean children with barley allergy.@*METHODS@#Forty-two participants with a history of ingesting barley who underwent serum specific immunoglobulin E to barley (barley-sIgE) assay at the Department of Pediatrics in Ajou Medical Center were enrolled through a retrospective analysis of medical records from March 2008 to February 2018. The demographic characteristics, symptoms, and immunologic parameters of the patients were assessed.@*RESULTS@#Twenty subjects presented with clinical barley allergy (B-allergic group), and 22 were atopic controls without allergic reactions after the ingestion of barley (B-tolerant group). The median ages of the B-allergic and B-tolerant groups were 1 and 3 years, respectively. In the B-allergic group, the cutaneous system (90.0%) was most frequently affected, followed by the respiratory system (40.0%). Anaphylaxis was observed in 35.0% of the B-allergic group. The median level of barley-sIgE was 13.90 kU(A)/L (range, 0.14–101.00 kU(A)/L) in the B-allergic group, and this value was significantly higher (P < 0.001) than that of the B-tolerant group (0.30 kU(A)/L; range, 0.01–24.40 kU(A)/L), with an optimal cutoff level of 1.24 kU(A)/L (sensitivity, 85.0%; specificity, 86.4%). A positive correlation was found between the serum levels of barley-sIgE and wheat-sIgE in the B-allergic group with clinical wheat allergy.@*CONCLUSION@#Barley is an important allergen for children in Korea. This study showed the clinical characteristics of barley allergy and suggested optimal cut-off levels of barley-sIgE for clinical barley allergy. Clinically, cross-reactivity or co-sensitization is often observed between barley and wheat.

Comparison of Effectiveness between Abdominal Vibration Stimulation and Walking Exercise for Bowel Cleansing before Therapeutic Colonoscopy

Background/Aims@#Adequate bowel preparation is important for successful colonoscopy. We aimed to evaluate the clinical feasibility and effectiveness of abdominal vibration stimulation in bowel preparation before therapeutic colonoscopy. @*Methods@#A single center, prospective, randomized, investigator-blinded study was performed between January 2016 and December 2016. Patients for therapeutic colonoscopy were prospectively enrolled and assigned to either the vibrator group or walking group. Patients who refused to participate in this study as part of the experimental group consented to register in the control group instead. During the preparation period, patients assigned to the walking group walked ≥3,000 steps, whereas those assigned to the vibrator group received abdominal vibrator stimulation and restricted walking. All patients received the same colon cleansing regimen: 4-L split-dose polyethylene glycol (PEG) solution. @*Results@#Three hundred patients who received PEG solution for therapeutic colonoscopy were finally enrolled in this study (n=100 per group). Bowel cleansing with abdominal vibration stimulation showed almost similar results to that with walking exercise (Boston Bowel Preparation Scale score for the entire colon: vibrator vs walking vs control, 7.38±1.55 vs 7.39±1.55 vs 6.17±1.15, p<0.001). There were no significant differences between the vibrator group and walking group regarding instances of diarrhea after taking PEG, time to first diarrhea after taking PEG, total procedure time, and patient satisfaction. @*Conclusions@#This study indicates that, compared with conventional walking exercise, abdominal vibration stimulation achieved similar rates of bowel cleansing adequacy and colonoscopy success without compromising safety or patient satisfaction.

Suicidal Risk in Depressed Patients with the Treatment by Antipsychotics and Antidepressant Compared to Antidepressant Monotherapy: A Pilot Study Using Psychiatric Common Data Model / 신경정신의학

Methods@#Using a common data model of electronic medical records at a university medical center in South Korea, the study populations were extracted if the depressive patients were treated either with antidepressants only or along with antipsychotics. The suicidal risks were compared with the Kaplan-Meier plot and log-rank test, and the risk factors were accessed using the Cox proportional hazard model. @*Results@#All demographic characteristics were similar in the monotherapy group taking only antidepressants and the combination therapy group taking antipsychotics with antidepressants, except for the smoking characteristic (p=0.023). The combination therapy group showed a lower suicidal risk [hazard ratio=0.58, 95% confidence interval (CI)=0.282–1.190] compared to the monotherapy group, which was not significant (p=0.138). @*Conclusion@#The combination therapy had no beneficial effects on reducing the suicidal risk in patients with depressive symptoms. This study is meaningful in that it is the first attempt to explore a psychiatric behavior/symptom using real-world data based on a common data model of general electronic medical records as well as narrative textual data.