Ewha Womans University Medical Center Research Articles

Predicting the Risk of Sleep Disorders Using a Machine Learning-Based Simple Questionnaire: Development and Validation Study.

Sleep disorders, such as obstructive sleep apnea (OSA), comorbid insomnia and sleep apnea (COMISA), and insomnia are common and can have serious health consequences. However, accurately diagnosing these conditions can be challenging as a result of the underrecognition of these diseases, the time-intensive nature of sleep monitoring necessary for a proper diagnosis, and patients' hesitancy to undergo demanding and costly overnight polysomnography tests. We aim to develop a machine learning algorithm that can accurately predict the risk of OSA, COMISA, and insomnia with a simple set of questions, without the need for a polysomnography test. We applied extreme gradient boosting to the data from 2 medical centers (n=4257 from Samsung Medical Center and n=365 from Ewha Womans University Medical Center Seoul Hospital). Features were selected based on feature importance calculated by the Shapley additive explanations (SHAP) method. We applied extreme gradient boosting using selected features to develop a simple questionnaire predicting sleep disorders (SLEEPS). The accuracy of the algorithm was evaluated using the area under the receiver operating characteristics curve. In total, 9 features were selected to construct SLEEPS. SLEEPS showed high accuracy, with an area under the receiver operating characteristics curve of greater than 0.897 for all 3 sleep disorders, and consistent performance across both sets of data. We found that the distinction between COMISA and OSA was critical for accurate prediction. A publicly accessible website was created based on the algorithm that provides predictions for the risk of the 3 sleep disorders and shows how the risk changes with changes in weight or age. SLEEPS has the potential to improve the diagnosis and treatment of sleep disorders by providing more accessibility and convenience. The creation of a publicly accessible website based on the algorithm provides a user-friendly tool for assessing the risk of OSA, COMISA, and insomnia.

Clinical applicability of an artificial intelligence prediction algorithm for early prediction of non-persistent atrial fibrillation.

It is difficult to document atrial fibrillation (AF) on ECG in patients with non-persistent atrial fibrillation (non-PeAF). There is limited understanding of whether an AI prediction algorithm could predict the occurrence of non-PeAF from the information of normal sinus rhythm (SR) of a 12-lead ECG. This study aimed to derive a precise predictive AI model for screening non-PeAF using SR ECG within 4 weeks. This retrospective cohort study included patients aged 18 to 99 with SR ECG on 12-lead standard ECG (10 seconds) in Ewha Womans University Medical Center for 3 years. Data were preprocessed into three window periods (which are defined with the duration from SR to non-PeAF detection) - 1 week, 2 weeks, and 4 weeks from the AF detection prospectively. For experiments, we adopted a Residual Neural Network model based on 1D-CNN proposed in a previous study. We used 7,595 SR ECGs (extracted from 215,875 ECGs) with window periods of 1 week, 2 weeks, and 4 weeks for analysis. The prediction algorithm showed an AUC of 0.862 and an F1-score of 0.84 in the 1:4 matched group of a 1-week window period. For the 1:4 matched group of a 2-week window period, it showed an AUC of 0.864 and an F1-score of 0.85. Finally, for the 1:4 matched group of a 4-week window period, it showed an AUC of 0.842 and an F1-score of 0.83. The AI prediction algorithm showed the possibility of risk stratification for early detection of non-PeAF. Moreover, this study showed that a short window period is also sufficient to detect non-PeAF.

Mask Depicting Smallpox Scars.

Department of Plastic Surgery, Armed Forces Capital Hospital, Bundang-gu, Seongnam-City, Gyeonggi-do, and Ewha Medical Academy, Ewha Womans University Medical Center, Seoul, Republic of Korea Address correspondence and reprint requests to Kun Hwang, MD, PhD, Department of Plastic Surgery, Armed Forces Capital Hospital, 81 Saemaeul-ro 177beon-gil, Bundang-gu, Seongnam-City, Gyeonggi-do, 13574, Republic of Korea, and Ewha Medical Academy, Ewha Womans University Medical Center, 260 Gonghang-daero, Gangseo-gu, Seoul, 07804, Republic of Korea; E-mail: [email protected] This study was supported by a grant from the National Research Foundation of Korea (NRF-2020R1I1A2054761). The author has no conflict of interest to declare.

PO-04-175 RECONSTRUCTING TWELVE-LEAD ELECTROCARDIOGRAM SIGNALS FROM A SINGLE-LEAD SIGNAL USING GENERATIVE ADVERSARIAL NETWORKS

Recently, many highly accurate artificial intelligence (AI)-based prediction models have been developed for 12-lead electrocardiogram (ECG) signals. Therefore, if one can faithfully reconstruct 12-lead signals from a single-lead signal, such prediction models can seamlessly be integrated into various wearable devices that measure only a single-lead ECG signal. We aim to verify the performance of AI model that constructs estimated 12-lead ECG signals from a single-lead ECG signal. To train and validate AI models, we used 36,610 12-lead standard ECG (10 seconds) signals recorded from Ewha Womans University Medical Center between 23 May 2017 and 2 September 2020. In this study, we examined whether it is possible to generate ECGs that reflect the characteristics of various cardiovascular diseases such as LBBB, RBBB, and AF. All input signals were normalized by using a bandpass filter and into [-1, 1]. To reconstruct 12-lead signals from a single-lead signal, we developed a novel conditional generative adversarial network, called EKGAN, which is based on Pix2Pix [1] and consists of two generators and one discriminator. Then, the performance of EKGAN was evaluated with respect to root mean square error (RMSE), mean absolute error (MAE) and percentage root mean squared difference (PRD). We used 36,610 and 9,154 ECGs to train and test AI models that generate other leads from a Lead I signal. Table 1 shows the performance of EKGAN and Pix2Pix for generating all lead signals except Lead I, where EKGAN outperformed Pix2Pix in terms of all measures. Figure 1 shows an example of original and generated 12-lead ECG signals by EKGAN and Pix2Pix using only the Lead I signal. Twelve-lead ECG signals can faithfully be reconstructed from a single-lead ECG signal by using our GAN-based reconstruction model, which opens up a wide range of medical applications of wearable ECG devices.

Number of Tumor Foci as a Risk Factor for Recurrence in Papillary Thyroid Carcinoma: Does It Improve Predictability?

Simple SummaryThyroid cancer is one of the most common cancers worldwide, and papillary thyroid carcinoma (PTC) comprises over 80% of all thyroid cancers. About 30% of patients with PTC have multifocality, which is useful for recurrence prediction. However, recent studies have suggested that the number of tumors, total tumor diameter, and bilaterality are more powerful predictors of recurrence than multifocality. Herein, we evaluated the effect of these factors on the predictability of recurrence in patients with PTC. Our study of 1288 patients confirmed that the number of tumors, total tumor diameter, and bilaterality could be independent predictors of recurrence even though they did not offer better predictability of recurrence than the prediction model using multifocality. Therefore, a simpler, multifocality-based prediction model would be sufficient for predicting recurrence in patients with PTC.Multifocality in papillary thyroid carcinoma (PTC) increases the risk of recurrence. Some recent studies have suggested that multifocality-related parameters, such as the number of tumor foci, total tumor diameter (TTD), and bilaterality, are more useful for predicting recurrence than multifocality. However, it is still unclear if these factors can improve the accuracy of the recurrence prediction model. Between 2012 and 2019, 1288 patients with PTC underwent total thyroidectomy at Ewha Womans University Medical Center. The 5-year disease-free survival rate was 91.2% in patients with >3 tumor foci, 95.1% with 3 foci, and 97.6% with 2 foci; conversely, those with a unifocal tumor showed a 5-year recurrence-free survival rate of 98.0%. Cox proportional hazards analysis indicated that the number of tumor foci (HR for >3 foci, 3.214; HR for 3 foci, 2.473), bilaterality (HR, 2.530), or TTD (HR for >3 cm, 5.359; HR for 2–3 cm, 3.584) could be an independent predictor of recurrence. However, models using the number of tumor foci, bilaterality, and TTD did not show better overall predictability of recurrence than models based on multifocality. In conclusion, a simpler prediction model based on multifocality may be sufficient.

Multi-center validation of machine learning model for preoperative prediction of postoperative mortality

Accurate prediction of postoperative mortality is important for not only successful postoperative patient care but also for information-based shared decision-making with patients and efficient allocation of medical resources. This study aimed to create a machine-learning prediction model for 30-day mortality after a non-cardiac surgery that adapts to the manageable amount of clinical information as input features and is validated against multi-centered rather than single-centered data. Data were collected from 454,404 patients over 18 years of age who underwent non-cardiac surgeries from four independent institutions. We performed a retrospective analysis of the retrieved data. Only 12–18 clinical variables were used for model training. Logistic regression, random forest classifier, extreme gradient boosting (XGBoost), and deep neural network methods were applied to compare the prediction performances. To reduce overfitting and create a robust model, bootstrapping and grid search with tenfold cross-validation were performed. The XGBoost method in Seoul National University Hospital (SNUH) data delivers the best performance in terms of the area under receiver operating characteristic curve (AUROC) (0.9376) and the area under the precision-recall curve (0.1593). The predictive performance was the best when the SNUH model was validated with Ewha Womans University Medical Center data (AUROC, 0.941). Preoperative albumin, prothrombin time, and age were the most important features in the model for each hospital. It is possible to create a robust artificial intelligence prediction model applicable to multiple institutions through a light predictive model using only minimal preoperative information that can be automatically extracted from each hospital.

Assessment of Change in Microbiology and Antibiotic Sensitivity of Deep Neck Infection Over 10 Years

Background and Objectives Treatment using systemic antibiotic administration and surgical drainage has been the common treatment modality for deep neck infection. This study compared the changing pattern of isolated pathogens to recommend the best empirical antibiotics for deep neck infection.Subjects and Method Reviewed retrospectively were medical charts of 131 patients who, confirmed with deep neck infection, underwent surgical drainage for pus cultures at Ewha Womans University Medical Center between January, 2009 and July, 2019. We analyzed the changing pattern of isolated pathogens and antibiotic susceptibility tests using their pus cultures.Results <i>Streptococcus viridans</i> was the most commonly isolated organism (35.1%), followed by <i>Klebsiella pneumonia</i> (13.7%) and <i>Staphylococcus aureus</i> (4.6%). The isolation rate of <i>Streptococcus viridans</i> increased in the recent 10 years [<i>p</i>=0.016, odds ratio (OR)=3.417]. Antibiotic susceptibility tests showed that all pathogens were resistant to ampicillin, but susceptible to ampicillin/sulbactam and cephalosporin. The isolation rate of clindamycin resistant pathogens was increased with statistical significance (<i>p</i>=0.020, OR=8.076).Conclusion Antibiotics effective against both <i>Streptococcus viridans</i> and <i>Klebsiella pneumonia</i> should be used as the first-line of treatment for deep neck infection. Ampicillin/sulbactam or amoxicillin/clavulanic acid were sufficient to treat deep neck infection empirically regardless of age or underlying diseases.

Prognosis of papillary thyroid cancer in patients with Graves\u2019 disease: a propensity score-matched analysis

BackgroundPatients with Graves’ disease (GD) are at a 2.5 times higher risk of developing thyroid cancer than the general population. Previous studies reported conflicting results about the prognosis of thyroid cancer concomitant with GD. This study aimed to investigate the effect of GD to the recurrence rates of papillary thyroid carcinoma (PTC).MethodsWe reviewed 3628 patients who underwent total thyroidectomy for PTC at the Ewha Womans University Medical Center from January 2006 to June 2014. Of those, 114 patients had non-occult PTC with concomitant GD. To reduce potential confounding effects and selection bias, we conducted 1:5 propensity score matching and analyzed the recurrence-free survival.ResultsThyroid cancer in patients with GD showed lower rate of lymphatic invasion (1.8% vs. 6.7%; p = 0.037), microscopic resection margin involvement (0.9% vs. 5.8%; p = 0.024), and lymph node metastasis (29.8% vs. 37.3%; p = 0.001) than in patients without GD, respectively. During the median follow-up of 94.1 months, recurrence occurred in one patient (0.9%) with GD. After propensity score matching for adjusting clinicopathological features, 5-year recurrence-free survival was comparable between patients with GD and euthyroid patients (100% vs. 98.4%, p = 0.572). Both tumor size [hazard ratio (HR) 1.585, p < 0.001] and lymph node metastasis (HR for N1a 3.067, p = 0.024; HR for N1b 15.65, p < 0.001) were predictive factors for recurrence-free survival, while GD was not associated with the recurrence.ConclusionsOur data suggest that GD does not affect the prognosis of PTC. Thyroid cancer in patients with GD is not more aggressive than in euthyroid patients.

Decision-making regarding withdrawal of life-sustaining treatment and the role of intensivists in the intensive care unit: a single-center study

BackgroundThis study examined the experience of withholding or withdrawing life-sustaining treatment in patients hospitalized in the intensive care units (ICUs) of a tertiary care center. It also considers the role that intensivists play in the decision-making process regarding the withdrawal of life-sustaining treatment.MethodsWe retrospectively analyzed the medical records of 227 patients who decided to withhold or withdraw life-sustaining treatment while hospitalized at Ewha Womans University Medical Center Mokdong between April 9 and December 31, 2018.ResultsThe 227 hospitalized patients included in the analysis withheld or withdrew from life-sustaining treatment. The department in which life-sustaining treatment was withheld or withdrawn most frequently was hemato-oncology (26.4%). Among these patients, the most common diagnosis was gastrointestinal tract cancer (29.1%). A majority of patients (64.3%) chose not to receive any life-sustaining treatment. Of the 80 patients in the ICU, intensivists participated in the decision to withhold or withdraw life-sustaining treatment in 34 cases. There were higher proportions of treatment withdrawal and ICU-to-ward transfers among the cases in whom intensivists participated in decision making compared to those cases in whom intensivists did not participate (50.0% vs. 4.3% and 52.9% vs. 19.6%, respectively).ConclusionsThrough their participation in end-of-life discussions, intensivists can help patients’ families to make decisions about withholding or withdrawing life-sustaining treatment and possibly avoiding futile treatments for these patients.

Anesthetic Management during Electroconvulsive Therapy

Some patients with depression require electroconvulsive therapy performed under general anesthesia. This requires rapid loss of consciousness, with minimal interference from seizure activity, appropriate muscle relaxation status, prevention of hyperdynamic responses to the electrical stimulus, and proper recovery of spontaneous ventilation and consciousness. The authors report the first case of electroconvulsive therapy performed with the patient under general anesthesia at the Ewha Womans University Medical Center, Korea.

Robotic single-site surgery in benign gynecologic diseases: Experiences and learning curve based on 626 robotic cases at a single institute.

The purpose of this study was to report on 626 cases of successful robotic single-site (RSS) surgeries to address various types of gynecologic disease and to evaluate the outcomes and learning curve inherent to RSS surgery in the gynecology field. A total of 626 cases of RSS surgeries were performed by 3 gynecologic surgeons at Ewha Womans University Medical Center, Robot Surgery Center from November 2014 to January 2018 were collected retrospectively. All of the patients' charts were reviewed, and the clinical characteristics and surgical variables were analyzed. Among the total of 626 cases, there were 220 cases of RSS myomectomy (RSSM), 182 cases of RSS hysterectomy (RSSH), 195 of RSS adnexectomy, 24 of RSS sacrocolpopexy (RSS SCP) and 5 were classified as other RSS surgeries. The patient's mean age was 38.98 ± 10.07 years. There was 3.99 ± 2.15 min of mean docking time and 117.78 ± 51.18 min of mean operating time. The surgical variables were analyzed annually. The total operating time was seen to decrease significantly according to each period. The docking time declined significantly and gradually after 1 year. We also analyzed each of the surgical types by time. The operating time of RSSH, RSSM, RSS adnexectomy and RSS SCP fell over time. The tendency found was for operating time to decline sharply following the first 10 cases. When we analyzed the data at annual intervals, the operating time was most significantly less and stable following the first year. There were a few intraoperative or perioperative complications in 16 cases (2.6%). Robotic single-site surgery is a feasible and safe procedure for treating various kinds of gynecologic diseases. The learning curve was approximately 10 cases of RSS surgery in gynecologic disease, having a greater amount of experience at performing RSS surgery was revealed to be key to achieving better surgical outcomes.

1644 1. Clinical Study and Evaluation of the Robotic Single-Site Hysterectomy

Study Objective The study aimed to discuss the safety, feasibility and advantages of the Robotic Single-Site hysterectomy (RSSH) in gynecological field. Design Retrospective analysis of 179 cases of RSSH Setting Department of Obstetrics and Gynecology, College of Medicine, Robot Surgery Center, Ewha Womans University Patients or Participants 179 patients who had RSSH Interventions From December 2014 to January 2019, 179 cases of Robotic Single-Site Hysterectomy which was done by 3 gynecologic surgeons at Ewha Womans University Medical Center were retrospectively analyzed. Measurements and Main Results There were total 179 cases of the Robotic Single-Site hysterectomy. One hundred seventy cases had adenomyosis, or leiomyoma or those combined diseases. The mean ages was 47.24±6.02. The mean total operation time was 120.44±40.61 mins, with the mean docking time 3.47±1.79 mins. The mean estimated blood loss (EBL) was 177.12±184.82 ml and the mean hemoglobin change was 1.92±0.95 g/dl. The mean hospitalization period was 4.98±1.24 days. Only few intraoperative or perioperative complication in 7cases (0.039%) were noted. The conversion rate to laparotomy was zero. Conclusion The Robotic Single-Site hysterectomy is a safe, reliable and feasible surgical method in gynecology.

The prevalence of colorectal polyps in patients with gastric cancer.

549 Background: Gastric polyps are found frequently in various colonic polyposis syndromes. Genetic alterations of several genes occur in gastric adenomas and colorectal adenomas. However, it is unknown whether patients with gastric cancers are at higher risk for colorectal adenomas. Methods: We retrospectively reviewed the medical records in 112 patients with gastric cancers from January 2005 to December 2009. Patients who were diagnosed with gastric cancers and had colonoscopy within 6 months were compared to 220 sex and age-matched controls from 3,725 persons who underwent esophagogastroduodenoscopy and colonoscopy for screening at the Center for Health Promotion in Ewha Womans University Medical Center. High risk polyp was defined by any of the following: (1) the presence of three or more polyps; (2) polyp size at least 10mm; (3) high-grade dysplasia or adenocarcinoma confirmed by histopathologic examination. Otherwise the polyps were defined as low risk. Results: Mean age was 59 years-old and 70% was male in patients with gastric cancer. Overweight (BMI ≥ 23) was more common in control group (gastric cancer versus control: 56% and 69%, respectively, P = 0.025). Colorectal polyps were identified in 67 of 112 patients (59.8%) with gastric cancer and in 153 of 220 controls (69.5%). The prevalence of high risk polyps were numerically higher in the gastric cancer group than the control group, although not statistically significant (9% vs. 4%, P = 0.267). In contrast, the prevalence of low risk polyps were significantly frequent in the control group (91% vs. 96%, P = 0.024). The mean size and number of colorectal polyps were not different between the two groups. Adenocarcinoma was diagnosed from polyps in five patients (7%) with gastric cancer and four patients (2%) with control group (P = 0.190). Conclusions: The overall colorectal polyps, especially low risk polyps, were more prevalent in the control group. In contrast, high risk polyps and adenocarcinoma is more frequently found in patients with gastric cancer although not significant. Therefore, we suggest that colorectal polyps should be cautiously examined in patients with gastric cancer.

Clinical Features and Response to UDCA Treatment of Primary Biliary Cirrhosis

Objectives: Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease that may progress to end stage liver cirrhosis. Benefits of ursodeoxycholic acid (UDCA) treatment has been investigated through large clinical studies. However, most of the studies were done in western countries and recent increase in prevalence of this relatively uncommon chronic liver disease draws attention in Korea. As early UDCA treatment effectively prevent the grave consequences of PBC progression, early diagnosis and lifelong management with UDCA is important. This study was designed to investigate the clinical features of PBC and response rates of UDCA treatments in Ewha Womans University Medical Center. Methods: Clinical data of PBC patients diagnosed between 2001 and 2014 at Ewha Womans University Medical Center were analyzed retrospectively. Results: A total of 35 patients with mean follow-up duration of 42 months were enrolled. At the diagnosis, 72.7% of the patients were asymptomatic, 5.7% had decompensated liver cirrhosis. The mean serum alkaline phosphate (ALP) level was 2.65 times upper limit of normal . UDCA was prescribed in 91.4% of the patients (n=32), among which 77.4% exhibited biochemical responses defined as serum ALP less than 2 upper limit of normal at 6 months (Mayo criteria). Conclusion: Most PBC patients were asymptomatic at the time of diagnosis and the average biochemical responses rate to UDCA treatment were ranged from 60.0% to 78.9% according to various response criteria. To elucidate the clinical features and courses of Korean PBC patients in detail, larger scale investigations and longer clinical follow up studies are warranted. (Ewha Med J 2015;38(3):106-111) Received July 8, 2015 Accepted September 17, 2015

The Future of Ewha Womans University Medical Center in Magok

The Future of Ewha Womans University Medical Center in Magok

The Etiological Spectrum of Acute Sensory Myelitis.

Background and PurposeAcute myelitis patients exhibiting only sensory deficits upon initial presentation are not commonly encountered in clinical practice, but they definitely exist. Since acute sensory myelitis has not been investigated previously, this study evaluated the etiological spectrum of the condition with the aim of describing the clinical characteristics thereof.MethodsPatients with acute myelitis who presented at the Ewha Womans University Medical Center (during 1999-2012) and the National Cancer Center (during 2005-2014) with only sensory symptoms as first clinical features were enrolled in this study. Their medical records, electrophysiological and laboratory data, and MRI findings were analyzed retrospectively.ResultsOf a total of 341 acute myelitis patients, 52 (15%) were identified as having acute sensory myelitis. The male-to-female ratio of these patients was 35:17, and their age at the onset of the condition was 41.7±10.5 years (mean±SD; range, 24-72 years). Acute sensory myelitis developed in patients with multiple sclerosis (MS; 14%), neuromyelitis optica spectrum disorder (NMOSD; 17%), and acute myelitis associated with concurrent systemic diseases including Behçet's disease and cancer (6%). Despite detailed evaluation, the etiology of 33 patients with acute myelitis could not be determined. Longitudinally extensive transverse myelitis on spinal MRI and progression of the sensory level were observed most commonly in NMOSD patients (89% and 78%, respectively); however, these patients did not exhibit sensory dissociation. Residual negative sensory symptoms were observed more frequently in NMOSD patients (33%) than in those with acute myelitis of unknown cause (24%) or MS (14%). During the long-term follow-up (4.7±2.7 years) of patients who did not undergo maintenance immunotherapy, a monophasic clinical course was common in those with acute myelitis of unknown cause (76%), but not in NMOSD or MS patients.ConclusionsAccurate identification of the diverse nature of acute sensory myelitis may assist in patient care.

Prognostic value of human apurinic/apyrimidinic endonuclease 1 (APE1) expression in breast cancer.

Human apurinic/apyrimidinic endonuclease 1 (APE1) is an essential protein for DNA base excision repair (BER) and redox regulation. The ability of cancer cells to recognize DNA damage and initiate DNA repair is an important mechanism for therapeutic resistance. Several recent studies have suggested that APE1 expression levels and/or subcellular dysregulation may be used to indicate the sensitivity of tumors to radiotherapy or chemotherapy. In this study, we assessed the prognostic significance of APE1 and differences in APE1 expression levels according to breast cancer molecular subtypes. We analyzed formalin-fixed, paraffin-embedded tumor tissue sections from 243 cases diagnosed as invasive breast cancer at Ewha Womans University Medical Center between January 2003 and December 2008. Immunohistochemistry was performed and the nuclear level of APE1 was scored by taking into account the percentage of positive cells. Medical records were reviewed to investigate clinicopathologic characteristics. We found that nuclear APE1 high-level expression (proportion ≥50%) in breast cancer showed a tendency towards unfavorable prognosis regarding disease-free survival (p = 0.093). However, there was no significant difference in overall survival between low and high-level expression groups (p = 0.294). Interestingly, within the Ki-67 low-level expression group, APE1 low-level expression was significantly associated with poor overall survival (p = 0.007). A significant positive correlation was observed between APE1 nuclear expression and estrogen receptor status (75.7% vs. 59.7%, p = 0.022). Also, the luminal A subtype was the most commonly observed breast cancer subtype in the APE1 high-level expression group (61.6% vs. 45.2%, p = 0.000). This study suggests that APE1 expression may be associated with breast cancer prognosis. In particular, its role as a prognostic factor would be significant for breast cancers with a low Ki-67 proliferation index. It is proposed that nuclear APE1 may be a novel target in breast cancer with a low proliferation rate to obtain better outcome.

The Association of Lung Age with Smoking Status in Korean Men

BackgroundLung age, calculated from sex, forced expiratory volume in one second (FEV1), and height, was developed to illustrate premature changes to the lungs and could be used to motivate smoking cessation. However, this method has not been tested in association with smoking in Korea. The purpose of this study was to investigate the association of lung age with smoking and other factors in Korean males.MethodsWe reviewed the records of 1,100 healthy men who visited a health promotion center at Ewha Womans University Medical Center from January 2008 to June 2009. Lung age was calculated from FEV1 and normal predictive values of spirometry according to age in the Korean population. The difference between lung age and chronological age was evaluated in relation to smoking status, weight, body mass index, waist, muscle mass, fat mass, and exercise.ResultsThe age difference was significantly higher in current smokers than in non-smokers (12.47 ± 19.90 vs. 7.30 ± 19.52, P < 0.001). Additionally, the age difference was positively correlated with life time pack-year (β = 0.223; P < 0.001) and fat mass (β = 0.462; P < 0.001). Lung age increased 1 year for 4.48 pack-year increase or for 2.16% increase in fat mass.ConclusionWe found a significant relationship between lung age and both smoking status and fat mass in healthy Korean males. Lung age may be a useful tool for motivating cessation of cigarette smoking and management of risk factors related to obesity.

Association of human adenovirus-36 in overweight Korean adults

Although human adenovirus-36 (Ad-36) has been reported to be associated with obesity in US adults and children, Korean children and the Italian population, the association has not been found in Dutch or Belgian populations or in US military subjects. Therefore, we examined whether Ad-36 infection is associated with obesity in Korean adults. A total of 540 age- and sex-matched individuals, who were normal weight, overweight or obese, were selected from participants in routine health examinations at the Ewha Womans University Medical Center. Overweight participants were defined as those with a body mass index (BMI) of 23 ≤ BMI<25 kg m(-2) and obese subjects were those with BMI ≥ 25 kg m(-2), according to the International Obesity Task Force definition. Ad-36 antibody was measured using a serum neutralization assay. Although more overweight participants than normal or obese subjects tested positive for the Ad-36 antibody (40%, 32.8% and 30%, respectively), the differences were not significant. The participants who tested positive for Ad-36 antibody had lower levels of triglycerides (TG) in each of the three groups, higher total cholesterol (TC) in the obese group and higher high-density lipoprotein-cholesterol (HDL-C) in both the normal and obese groups. The odds ratio (OR) for Ad-36 antibody positivity was greater in overweight than in normal subjects (OR=2.03; 95% confidence interval (CI), 1.16-3.55) after adjusting for age, sex and waist circumference. However, this OR was non-significant in the obese group (OR=1.56; 95% CI, 0.67-3.67). Ad-36 seems to be strongly associated with overweight, but not obese, Korean adults.

The Clinical Features and Management of IHPS: A Comparison between 1980's and 2000's

Purpose: A precise and simple tool for diagnosis and the growing public interest in health caused infantile hypertrophic pyloric stenosis (IHPS) to be diagnosed in good time. The approach to pyloromyotomy as the standard treatment is undergoing changes. We compared 2000’s IHPS patients with 1980’s to identify the clinical features and management. Methods: We analyzed, retrospectively, the clinical findings, diagnoses, and treatment of 68 patients with IHPS who underwent pyloromyotomy at Ewha Womans University Medical Center from January 2000 to December 2008 (2000’s group), and compared the results with that of 42 patients in the 1980’s (1980’s group). Results: There were no significant differences in age, gender, birth rank, seasonal distribution, and symptoms between both groups, but the number of patients with metabolic changes and palpable ‘olive’ was significantly lesser in the 2000’s group. Upper gastrointestinal series (UGI) was the most common imaging tool in the 1980’s (71.4%) but USG has become the standard diagnostic tool in the 2000’s (88.2%). All patients received open pyloromyotomy using traditional incision in the 1980’s, and supraumbilical semicircular incision in 36.8% of patients in the 2000’s. The average length of hospital stay after operation was significantly shorter in the 2000’s group. In the 2000’s, the mean preoperative stay at hospital was 4.4±4.3 days. Twenty-nine (42.0%) patients did not vomit postoperatively and postoperative vomiting did not delay discharges of any patients. Conclusion: There were significant improvements in diagnosis and treatment in the 2000’s. We suggest that the surgeon, without the need for a radiologist perform USG for IHPS in order to shorten the preoperative hospital stay.