Background: Respiratory pathogen infections and air pollution are main causes of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Air pollution has a direct effect on the airway epithelial barrier and the immune system, which can have an influence on infection. However, studies on the relationship between respiratory infections and air pollutants in severe AECOPD are limited. Thus, the objective of this study was to investigate the correlation between air pollution and respiratory pathogen in severe AECOPD. Methods: This multicenter observational study was conducted by reviewing electronic medical records of patients with AECOPD at 28 hospitals in South Korea. Patients were divided into four groups according to the comprehensive air-quality index (CAI) used in Korea. Identification rates of bacteria and viruses of each group were analyzed. Results: Viral pathogens were identified in 270 (36.7%) of 735 patients. Viral identification rate was different (P = 0.012) according to air pollution. Specifically, the virus detection rate was 55.9% in the group of CAI ‘D’ with the highest air pollution. It was 24.4% in the group of CAI ‘A’ with the lowest air pollution. This pattern was clearly seen for influenza virus A (P = 0.042). When further analysis was performed with particulate matter (PM), the higher/lower the PM level, the higher/lower the virus detection rate. However, no significant difference was found in the analysis related to bacteria. Conclusion Air pollution may make COPD patients more susceptible to respiratory viral infections, especially influenza virus A. Thus, on days with poor air quality, COPD patients need to be more careful about respiratory infections.

Background: Although respiratory tract infection is one of the most important factors triggering acute exacerbation of chronic obstructive pulmonary disease (AE-COPD), limited data are available to suggest an epidemiologic pattern of microbiology in South Korea. Methods: A multicenter observational study was conducted between January 2015 and December 2018 across 28 hospitals in South Korea. Adult patients with moderate-to-severe acute exacerbations of COPD were eligible to participate in the present study. The participants underwent all conventional tests to identify etiology of microbial pathogenesis. The primary outcome was the percentage of different microbiological pathogens causing AE-COPD. A comparative microbiological analysis of the patients with overlapping asthma–COPD (ACO) and pure COPD was performed. Results: We included 1,186 patients with AE-COPD. Patients with pure COPD constituted 87.9% and those with ACO accounted for 12.1%. Nearly half of the patients used an inhaled corticosteroid-containing regimen and one-fifth used systemic corticosteroids. Respiratory pathogens were found in 55.3% of all such patients. Bacteria and viruses were detected in 33% and 33.2%, respectively. Bacterial and viral coinfections were found in 10.9%. The most frequently detected bacteria were Pseudomonas aeruginosa (9.8%), and the most frequently detected virus was influenza A (10.4%). Multiple bacterial infections were more likely to appear in ACO than in pure COPD (8.3% vs. 3.6%, p=0.016). Conclusion Distinct microbiological patterns were identified in patients with moderate-to-severe AE-COPD in South Korea. These findings may improve evidence-based management of patients with AE-COPD and represent the basis for further studies investigating infectious pathogens in patients with COPD.

OBJECTIVES: To investigate if vitamin D receptor (VDR) gene polymorphisms and circulating vitamin D levels are associated with pelvic floor disorders (PFDs). METHODS: In this case-control study, 25-hydroxy-vitamin D (25[OH]D) serum levels were analyzed in 47 females with PFDs and 87 healthy females (controls), respectively. The VDR gene polymorphisms were determined by using polymerase chain reaction and performing digestions with 4 restriction enzymes i.e., ApaI, TaqI, FokI, and BsmI. Vitamin D levels of patients were divided into <20 ng/mL, 20 to 30 ng/mL, and ≥30 ng/mL categories. RESULTS: Our correlative analysis of VDR polymorphisms as a function of the presence of PFD showed that ApaI and BsmI polymorphisms were significantly associated with PFD in vitamin-D-deficiency and insufficiency groups (P < 0.05). Mean vitamin D levels did not differ between the PFD case (13.01 ± 0.84 ng/mL) and control (15.11 ± 1.04 ng/mL) groups (P > 0.05). However, there was a significant difference in the distribution of vitamin D levels between study group and controls using Pearson's χ2 test (<20 ng/mL, 20–30 ng/mL, and >30 ng/mL: 87.2%, 12.8%, and 0% in the study group and 75.9%, 16.1%, and 8.0% in controls, respectively, P < 0.05). Taken together, our observations suggest that vitamin D levels could be associated with PFDs and that 2 polymorphisms (i.e., ApaI and BsmI) in the VDR gene may contribute to an increased prevalence of PFDs in women with insufficient levels of vitamin D. CONCLUSIONS: Examining vitamin D levels and performing a VDR genotype analysis may be helpful for assessing PFD risk.
Case-Control Studies ; Female ; Genotype ; Humans ; Pelvic Floor Disorders ; Pelvic Floor ; Polymerase Chain Reaction ; Prevalence ; Receptors, Calcitriol ; Vitamin D Deficiency ; Vitamin D ; Vitamins

BACKGROUND/AIMS: In addition to the globally endorsed Barcelona Clinic Liver Cancer (BCLC) staging system, other algorithms or staging systems have been developed, including the Hong Kong Liver Cancer (HKLC) staging system. This study aimed to validate the HKLC staging system relative to the BCLC staging system for predicting survival for hepatocellular carcinoma (HCC) patients in Korea. METHODS: From 2004 to 2013, 2,571 patients newly diagnosed with HCC were consecutively enrolled at three Korea University medical centers. RESULTS: Both staging systems differentiated survival well (p < 0.001). However, 1-year and 3-year survival were predicted better using the HKLC system than the BCLC system (area under the receiver operating characteristic curve: 0.869 vs 0.856 for 1 year, p=0.002; 0.841 vs 0.827 for 3 years, p=0.010). In hypothetical survival curves, the HKLC system exhibited better median overall survival than the BCLC system (33.1 months vs 19.2 months). In evaluations of prognosis according to either BCLC or HKLC treatment guidelines, risk of death was reduced in the group following only HKLC guidelines compared with the group following only BCLC guidelines (hazard ratio, 0.601; 95% confidence interval, 0.443 to 0.816; p=0.001). CONCLUSIONS: Although both staging systems predicted and discriminated HCC prognoses well, the HKLC system showed more encouraging survival benefits than the BCLC system.
Academic Medical Centers ; Carcinoma, Hepatocellular ; Hong Kong ; Humans ; Korea ; Liver Neoplasms ; Liver ; Neoplasm Staging ; Prognosis ; ROC Curve

BACKGROUND: The purpose of this study was to assess the effect of our new video-assisted asthma education program on patients' knowledge regarding asthma and asthma control. METHODS: Adult asthmatics who were diagnosed by primary care physicians and followed for at least 1 year were educated via smart devices and pamphlets. The education sessions were carried out three times at 2-week intervals. Each education period lasted at most 5 minutes. The effectiveness was then evaluated using questionnaires and an asthma control test (ACT). RESULTS: The study enrolled 144 patients (mean age, 56.7±16.7 years). Half of the patients had not been taught how to use their inhalers. After participating in the education program, the participants' understanding of asthma improved significantly across all six items of a questionnaire assessing their general knowledge of asthma. The proportion of patients who made errors while manipulating their inhalers was reduced to less than 10%. The ACT score increased from 16.6±4.6 to 20.0±3.9 (p<0.001). The number of asthmatics whose ACT score was at least 20 increased from 45 (33.3%) to 93 (65.3%) (p<0.001). The magnitude of improvement in the ACT score did not differ between patients who received an education session at least three times within 1 year and those who had not. The majority of patients agreed to the need for an education program (95.8%) and showed a willingness to pay an additional cost for the education (81.9%). CONCLUSION: This study indicated that our newly developed education program would become an effective component of asthma management in primary care clinics.
Adult ; Asthma* ; Education* ; Humans ; Nebulizers and Vaporizers ; Pamphlets ; Physicians, Primary Care ; Primary Health Care*

BACKGROUND: Enquiry into smoking status and recommendations for smoking cessation is an essential preventive service. However, there are few studies comparing self-reported (SR) and cotinine-verified (CV) smoking statuses, using medical check-up data. The rates of discrepancy and under-reporting are unknown. METHODS: We performed a cross-sectional study using health examination data from Healthcare System Gangnam Center, Seoul National University Hospital in 2013. We analyzed SR and CV smoking statuses and discrepancies between the two in relation to sociodemographic variables. We also attempted to ascertain the factors associated with a discrepant smoking status among current smokers. RESULTS: In the sample of 3,477 men, CV smoking rate was 11.1% higher than the SR rate. About 1 in 3 participants either omitted the smoking questionnaire or gave a false reply. The ratio of CV to SR smoking rates was 1.49 (95% confidence interval [CI], 1.38-1.61). After adjusting for confounding factors, older adults (≥60 years) showed an increased adjusted odds ratio (aOR) for discrepancy between SR and CV when compared to those in their twenties and thirties (aOR, 5.43; 95% CI, 2.69-10.96). Educational levels of high school graduation or lower (aOR, 2.33; 95% CI, 1.36-4.01), repeated health check-ups (aOR, 1.45; 95% CI, 1.03-2.06), and low cotinine levels of <500 ng/mL (aOR, 2.03; 95% CI, 1.33-3.09), were also associated with discordance between SR and CV smoking status. CONCLUSION: Omissions and false responses impede the accurate assessment of smoking status in health check-up participants. In order to improve accuracy, it is suggested that researcher pay attention to participants with greater discrepancy between SR and CV smoking status, and formulate interventions to improve response rates.
Adult* ; Cotinine ; Cross-Sectional Studies ; Delivery of Health Care ; Hospitals, Private* ; Humans ; Male* ; Mass Screening ; Odds Ratio ; Self Report ; Seoul ; Smoke* ; Smoking Cessation ; Smoking* ; Surveys and Questionnaires

BACKGROUND: Low levels of physical activity can cause various physical symptoms or illness. However, few studies on this association have been conducted in young adults. The aim of this study was to investigate the association between physical activity levels and physical symptoms or illness in young adults. METHODS: Subjects were university students who participated in a web-based self-administered questionnaire in a university in Seoul in 2013. We obtained information on physical activities and physical symptoms or illness in the past year. Independent variables were defined as symptoms or illness which were associated with decreased academic performance. Logistic regression was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of each physical symptom or illness with adjustment for covariables. RESULTS: A total of 2,201 participants were included in the study. The main physical symptoms or illness among participants were severe fatigue (64.2%), muscle or joint pain (46.3%), gastrointestinal problems (43.1%), headache or dizziness (38.6%), frequent colds (35.1%), and sleep problems (33.3%). Low physical activity levels were significantly associated with high ORs of physical symptoms or illness. Multivariable-adjusted ORs (95% CIs) in the lowest vs. highest tertile of physical activity were 1.45 (1.14–1.83) for severe fatigue, 1.35 (1.07–1.70) for frequent colds, and 1.29 (1.02–1.63) for headaches or dizziness. We also found that lower levels of physical activity were associated with more physical symptoms or bouts of illness. CONCLUSION: Low physical activity levels were significantly associated with various physical symptoms or illness among university students. Also, individuals in the lower levels of physical activity were more likely to experience more physical symptoms or bouts of illness than those in the highest tertile of physical activity.
Arthralgia ; Common Cold ; Dizziness ; Fatigue ; Gastrointestinal Diseases ; Headache ; Humans ; Korea* ; Logistic Models ; Motor Activity* ; Myalgia ; Odds Ratio ; Seoul ; Young Adult

BACKGROUND: Postmenopausal osteoporosis is a common disease which can cause various morbidity and economic burden. Lactation is known to cause a decline in bone mineral density (BMD), but there are controversies on whether decreased BMD is fully recovered after lactation and whether lactation duration has an influence on postmenopausal BMD. This study was conducted to see whether breastfeeding is associated with postmenopausal bone loss using a highly representative sample of Korean population. METHODS: Retrospective cross sectional study was done using data collected from Korea National Health and Nutrition Examination Survey V. The study outcome was BMD measured with dual-energy X-ray absorptiometry and divided into 2 groups: normal or low BMD (T score<-1), and breastfeeding duration was categorized into 4 groups (never, 1st, 2nd, and 3rd tertile). Logistic regression analysis was done to examine the association between lactation duration and BMD. RESULTS: Among 1,694 postmenopausal women (mean age, 63.5+/-9.1), 85.71% were in low BMD group. Compared to never breastfeeding group, postmenopausal women with longer than 79 months of breastfeeding duration are more likely to have low BMD (adjusted risk ratio [ARR]=1.24; 95% confidence interval, 1.17 to 1.32). As the duration of breastfeeding increases, ARR and risk difference for low BMD also increases (P for trend=0.008). CONCLUSION: The study results showed that total breastfeeding duration was associated with postmenopausal low BMD. All women planning on breastfeeding should be aware of its risks and should take adequate dietary calcium and vitamin D before, during, and after breastfeeding.
Absorptiometry, Photon ; Bone Density ; Breast Feeding* ; Breast* ; Calcium, Dietary ; Female ; Humans ; Korea* ; Lactation ; Logistic Models ; Nutrition Surveys* ; Odds Ratio ; Osteoporosis, Postmenopausal* ; Retrospective Studies ; Vitamin D

BACKGROUND: The effect of dietary fat intake on the risk of cardiovascular disease remains unclear. We investigated the association between dietary fat and specific types of fat intake and the risk of metabolic syndrome. METHODS: The study population included 1,662 healthy adults who were 50.2 years of age and had no known hypertension, diabetes, hyperlipidemia, or metabolic syndrome at the initial visit. Dietary intake was obtained from a 1-day food record. During 20.7 months of follow-up, we documented 147 cases of metabolic syndrome confirmed by self-report, anthropometric data, and blood test results. The intakes of total fat, vegetable fat, animal fat, saturated fatty acid (SFA), polyunsaturated fatty acid (PUFA), monounsaturated fatty acid (MUFA), and cholesterol level divided by quintile. Multivariate analyses included age, sex, body mass index, smoking status, alcohol intake, physical activity, total calorie, and protein intake. RESULTS: Vegetable fat intake was inversely associated with metabolic syndrome risk (odds ratio for the highest vs. the lowest quintile, 0.33; 95% confidence interval, 0.14 to 0.76). Total fat, animal fat, SFA, PUFA, MUFA, and cholesterol intakes showed no association with metabolic syndrome. Vegetable fat intake was inversely associated with the risk of hypertriglyceridemia among the components of metabolic syndrome. CONCLUSION: These data support an inverse association between vegetable fat and the risk of metabolic syndrome.
Adult* ; Animals ; Body Mass Index ; Cardiovascular Diseases ; Cholesterol ; Dietary Fats* ; Follow-Up Studies ; Hematologic Tests ; Humans ; Hyperlipidemias ; Hypertension ; Hypertriglyceridemia ; Motor Activity ; Multivariate Analysis ; Smoke ; Smoking ; Vegetables

BACKGROUND/AIMS: Gastroesophageal reflux disease (GERD) is the most frequent cause of noncardiac chest pain (NCCP) in Western countries. Gastroduodenal disease has a high prevalence in Korea; thus, it is important to evaluate the stomach/duodenum. We retrospectively reviewed the findings in patients with chest pain who were diagnosed by coronary angiography (CAG) to be normal or who had minimal coronary lesions to evaluate the necessity of performing esophagogastroduodenoscopy (EGD) in patients with NCCP. METHODS: A total of 565 patients with chest pain underwent CAG followed by EGD from February 2000 to March 2011 at Konyang University Hospital. We excluded patients who underwent EGD more than 3 days after CAG or had significant coronary lesions. We retrospectively reviewed the EGD findings of the remaining 349 patients. RESULTS: Of the 349 patients, 151 were male, and the average age of the patients was 57.7+/-11.44 years. After performing EGD, GERD was diagnosed in 35 patients (10.0%; LA [Los Angeles classification]-A, 30; LA-B, three; LA-C, two) and peptic ulcer was diagnosed in 48 patients (13.8%; gastric ulcer, 34; duodenal ulcer, 10; gastric and duodenal ulcer, four). Gastritis was diagnosed in 253 patients (72.5%; erosive, 89; erythematous, 90; hemorrhagic, 10; mixed, 64). Duodenitis, esophagitis, Barrett's esophagus, hiatus hernia, and gastric cancer was diagnosed in 36 (10.3%), three (0.9%), two (0.6%), three (0.9%), and one patient, respectively. CONCLUSIONS: Unlike the situation in the west, stomach/duodenal lesions other than GERD are common causes of NCCP in Korea, Therefore, prior to proton pump inhibitor testing or empirical therapy, EGD is necessary to evaluate NCCP and to rule out gastroduodenal lesions.
Barrett Esophagus ; Chest Pain ; Coronary Angiography ; Duodenal Ulcer ; Duodenitis ; Endoscopy ; Endoscopy, Digestive System ; Endoscopy, Gastrointestinal ; Esophagitis ; Gastritis ; Gastroesophageal Reflux ; Hernia, Hiatal ; Humans ; Korea ; Male ; Peptic Ulcer ; Prevalence ; Proton Pumps ; Retrospective Studies ; Stomach Neoplasms ; Stomach Ulcer ; Thorax