The short-term effect of ambient particulate matter on suicide death.

BACKGROUND: Air pollution can cause various respiratory and neurological diseases and continuous exposure can lead to death. Previous studies have reported that particulate matter (PM) exposure increases the risk of depression, suicidal thoughts, and suicidal death; however, the results are inconsistent and limited. This study aimed to examine the relationship between short-term PM exposure and suicide deaths, as well as investigate the short-term effects of PM on suicide death within vulnerable groups based on factors such as sex, age group, suicide-related information (note, method, and cause), psychiatric disorders, and physical diseases. METHODS: Data on a total of 28,670 suicide deaths from 2013 to 2017, provided by the Korea Foundation for Suicide Prevention, were analyzed. The study design employed a time-series analysis with a two-stage approach. In the first step, a generalized additive model combined with a distributed lag nonlinear model was used to estimate the short-term effect of PM exposure on suicide risk specific to each city. In the second step, the estimated results from each city were pooled through a meta-analysis to derive the overall effect. We determined the effects of single lag, cumulative lag, and moving average PM concentrations from days 0-7 before suicide. RESULTS: We confirmed an association between exposure to PM10 (≤ 10 µm in diameter) and deaths due to suicide. In particular, among individuals with psychiatric disorders and those who employed non-violent suicide methods, increased exposure to PM10 was associated with a higher risk of death by suicide, with percentage changes of 5.92 (95% confidence interval [CI]: 3.95-7.92) and 11.47 (95% CI: 7.95-15.11), respectively. Furthermore, in the group with psychiatric disorders, there was an observed tendency of increasing suicide risk as PM10 levels increased up to 120 µg/m3, whereas in the group with non-violent suicide deaths, there was a pronounced trend of rapid increase in suicide risk with an increase in PM10 up to 100 µg/m3. CONCLUSIONS: These results show an association between short-term exposure to PM and suicide. Our study adds evidence for the benefits of reducing PM in preventing diseases and improving mental health.

Estimation of Attributable Risk and Direct Medical and Non-Medical Costs of Major Mental Disorders Associated With Air Pollution Exposures Among Children and Adolescents in the Republic of Korea, 2011-2019.

BACKGROUND: Recent studies have reported the burden of attention deficit hyperactivity disorder [ADHD], autism spectrum disorder [ASD], and depressive disorder. Also, there is mounting evidence on the effects of environmental factors, such as ambient air pollution, on these disorders among children and adolescents. However, few studies have evaluated the burden of mental disorders attributable to air pollution exposure in children and adolescents. METHODS: We estimated the risk ratios of major mental disorders (ADHD, ASD, and depressive disorder) associated with air pollutants among children and adolescents using time-series data (2011-2019) obtained from a nationwide air pollution monitoring network and healthcare utilization claims data in the Republic of Korea. Based on the estimated risk ratios, we determined the population attributable fraction (PAF) and calculated the medical costs of major mental disorders attributable to air pollution. RESULTS: A total of 33,598 patients were diagnosed with major mental disorders during 9 years. The PAFs for all the major mental disorders were estimated at 6.9% (particulate matter < 10 µm [PM10]), 3.7% (PM2.5), and 2.2% (sulfur dioxide [SO2]). The PAF of PM10 was highest for depressive disorder (9.2%), followed by ASD (8.4%) and ADHD (5.2%). The direct medical costs of all major mental disorders attributable to PM10 and SO2 decreased during the study period. CONCLUSION: This study assessed the burden of major mental disorders attributable to air pollution exposure in children and adolescents. We found that PM10, PM2.5, and SO2 attributed 7%, 4%, and 2% respectively, to the risk of major mental disorders among children and adolescents.

Development and Validation of a Real-Time Service Model for Noise Removal and Arrhythmia Classification Using Electrocardiogram Signals.

Arrhythmias range from mild nuisances to potentially fatal conditions, detectable through electrocardiograms (ECGs). With advancements in wearable technology, ECGs can now be monitored on-the-go, although these devices often capture noisy data, complicating accurate arrhythmia detection. This study aims to create a new deep learning model that utilizes generative adversarial networks (GANs) for effective noise removal and ResNet for precise arrhythmia classification from wearable ECG data. We developed a deep learning model that cleans ECG measurements from wearable devices and detects arrhythmias using refined data. We pretrained our model using the MIT-BIH Arrhythmia and Noise databases. Least squares GANs were used for noise reduction, maintaining the integrity of the original ECG signal, while a residual network classified the type of arrhythmia. After initial training, we applied transfer learning with actual ECG data. Our noise removal model significantly enhanced data clarity, achieving over 30 dB in a signal-to-noise ratio. The arrhythmia detection model was highly accurate, with an F1-score of 99.10% for noise-free data. The developed model is capable of real-time, accurate arrhythmia detection using wearable ECG devices, allowing for immediate patient notification and facilitating timely medical response.

Risk of uterine cervical cancer in inflammatory bowel disease: a systematic review and meta-analysis.

BACKGROUND AND AIMS: There are limited data on the association between uterine cervical cancer (UCC) and inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC). METHODS: This systematic review and meta-analysis assessed the risk of UCC in patients with IBD. We searched MEDLINE, Embase, Cochrane Library, Scopus, Web of Science, ClinicalTrials.gov, gray literature and conference proceedings for studies published before 21 January 2022. Two reviewers independently screened studies, extracted data and assessed quality using the Newcastle-Ottawa Scale. Subgroup analyses were based on IBD type, biologic era, immunosuppression status, study location and design, and publication status. Fifteen studies were included. RESULTS: The pooled relative risk (RR) of UCC in IBD was 1.34 (95% confidence interval [CI], 1.07-1.69; I2 = 53.4%). In subgroup analyses, the pooled RRs of UCC in CD and UC were 1.18 (95% CI, 0.97-1.42) and 1.50 (95% CI, 1.01-12.21), respectively. The pooled RRs of UCC in pre-biologic and biologic eras were 1.36 (95% CI, 0.83-2.23) and 1.99 (95% CI, 1.03-3.86), respectively. The pooled RR of UCC in immunomodulator users was 2.18 (95% CI, 0.81-5.87). The pooled RRs of UCC in Asia, Europe and North America were 5.65 (95% CI, 2.65-12.07), 1.13 (95% CI, 0.96-1.34) and 1.38 (95% CI, 1.10-1.73), respectively. CONCLUSIONS: The risk of UCC was significantly increased in IBD, particularly in UC but not in CD, suggesting that women with IBD should undergo regular UCC screening and consider vaccination.

Survival Benefit of Kidney Transplantation in Patients With End-Stage Kidney Disease and Prior Acute Myocardial Infarction.

Patients with end stage kidney disease (ESKD) and a previous acute myocardial infarction (AMI) have less access to KT. Data on ESKD patients with an AMI history who underwent first KT or dialysis between January 2007 and December 2018 were extracted from the Korean National Health Insurance Service. Patients who underwent KT (n = 423) were chronologically matched in a 1:3 ratio with those maintained on dialysis (n = 1,269) at the corresponding dates, based on time-conditional propensity scores. The 1, 5, and 10 years cumulative incidences for all-cause mortality were 12.6%, 39.1%, and 60.1% in the dialysis group and 3.1%, 7.2%, and 14.5% in the KT group. Adjusted hazard ratios (HRs) of KT versus dialysis were 0.17 (95% confidence interval [CI], 0.12-0.24; p < 0.001) for mortality and 0.38 (95% CI, 0.23-0.51; p < 0.001) for major adverse cardiovascular events (MACE). Of the MACE components, KT was most protective against cardiovascular death (HR, 0.23; 95% CI, 0.12-0.42; p < 0.001). Protective effects of KT for all-cause mortality and MACE were consistent across various subgroups, including patients at higher risk (e.g., age >65 years, recent AMI [<6 months], congestive heart failure). KT is associated with lower all-cause mortality and MACE than maintenance dialysis patients with a prior AMI.

Pregnancy complications and endometrial cancer in women with polycystic ovarian syndrome: a Korean National Health Insurance Service study.

OBJECTIVE: Polycystic ovarian syndrome is associated with diverse pregnancy related complications and endometrial cancer. However, research on the relationship between pregnancy complications and endometrial cancer in women with polycystic ovarian syndrome is scarce. We aimed to examine the association between gestational diabetes mellitus, pregnancy induced hypertension, and preterm birth and the risk of endometrial cancer in women with polycystic ovarian syndrome. METHODS: We analyzed data from the National Health Information Database established by the Korean National Health Insurance Service between January 2002 and December 2019. We included women with gestational diabetes mellitus, pregnancy induced hypertension, preterm birth, and endometrial cancer from among the polycystic ovarian syndrome population. All conditions were diagnosed according to the Korean Informative Classification of Diseases, 10th revision codes. Age, area of residence, income, body mass index, waist circumference, total cholesterol, high density lipoprotein, low density lipoprotein, triglycerides, fasting blood sugar, and creatinine levels were included as covariates in the multiple logistic regression analysis. RESULTS: Of 467 221 women with polycystic ovarian syndrome included, 5099 had endometrial cancer. Age, residence, income, body mass index, waist circumference, total cholesterol, high density lipoprotein, low density lipoprotein, triglycerides, fasting blood sugar, and creatinine levels differed significantly between the endometrial cancer and non-endometrial cancer groups (p≤0.001-0.032). Among the polycystic ovarian syndrome population, the odds ratios (ORs) of endometrial cancer were 1.50, 1.43, and 1.23 in women with a history of gestational diabetes mellitus, pregnancy induced hypertension, and preterm birth, respectively, compared with those without a history of these conditions (OR 1.50, 95% confidence interval (CI) 1.32 to 1.69, p<0.001; 1.43, 1.04 to 1.97, p=0.027; and 1.23, 1.05 to 1.45, p=0.011, respectively). CONCLUSION: Our results suggest that a history of pregnancy complications (gestational diabetes mellitus, pregnancy induced hypertension, and preterm birth) increases the risk of endometrial cancer in women with polycystic ovarian syndrome.

Prevalence of motor neuron diseases in gout patients: a nationwide population-based cohort study.

BACKGROUND: Increased uric acid may have a protective effect in motor neuron diseases (MNDs). The association between gout, characterized by hyperuricemia, and MNDs was not investigated previously. To estimate the prevalence of MNDs in gout patients using the Health Insurance and Review Assessment (HIRA) database, a nationwide database of South Korea. METHODS: The current descriptive study was conducted using the HIRA database. Subjects diagnosed with gout from 2011 to 2018 were included in this study. Among them, the annual prevalence of MNDs was analyzed, stratified by age and sex. Comorbidities including the Charlson Comorbidity Index score and type of prescribed gout-related drug were also demonstrated. RESULTS: The age-adjusted prevalence of MNDs per 105 persons ranged from 0.598 (95% confidence interval (CI): - 0.231-1.426) to 2.534 (95% CI: 1.100-3.968) between 2011 and 2018. Compared to previous reports, the prevalence of MNDs, especially amyotrophic lateral sclerosis (ALS), in gout patients was significantly lower than in the general population. None of the female gout patients were diagnosed with MNDs. Cerebrovascular accidents, vascular risk factors including hypertension, dyslipidemia, and diabetic complications, and the use of uric acid-lowering agents were more common in gout patients with MNDs than in those without MNDs. CONCLUSION: This study adds to the evidence of MND prevalence in gout patients. Gout might have a protective effect against the risk of MNDs.

Factors Related to Suicidal Ideation by Gender and Age Group in Korean Adults.

BACKGROUND: According to the results of the age-standardized suicide rate (suicide deaths per 100,000 population) published by Organization for Economic Cooperation and Development countries from 2003 to 2019, the suicide rate in Korea is ranked first almost every year, so it should be managed at the national level. To reduce the suicide rate, many scholars are studying suicide. The suicidal process begins with suicidal ideation, progresses through suicide attempts, and ends with suicide. Among them, the frequency of suicidal thoughts was found to be highly correlated with suicide plans and attempts, and it is said that 60% of those who change from suicidal ideation to attempts appear within one year. Therefore, research related to suicidal ideation to lower the suicide rate will contribute to preventing suicide at an early stage. METHODS: This study used data from the Korea National Health and Nutrition Examination Survey (KNHANES). Among them, data from 2013, 2015, 2017, and 2019 surveyed adults were compared for suicidal ideation among 18,339 adults. Considering the characteristics of the KNHANES data, complex sample analysis was performed considering the primary extraction unit (region), stratification variables, and weights. The Rao-Scott χ² test was stratified by age group to confirm the distribution of suicidal ideation according to general characteristics. Univariate and multiple logistic regression analyses were performed to understand the effect on suicidal ideation. RESULTS: Among all subjects, the rate of suicidal ideation was 4.75%, and among the age groups, the rate of suicidal thoughts was the highest among those over 80 years old (10.39%). Compared to those who were 50s, those in their 30s had the lowest suicidal ideation (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.39-0.70), and those in their 80s had the highest rate of suicidal ideation (OR, 1.97; 95% CI, 1.38-2.82). Except for those in their 20s, the rate of suicidal ideation tends to increase with age. Overall, the lower 25% of the Euro Quality of Life-5 Dimensions (EQ-5D) index, depression lasting more than two weeks, and subjects with poor subjective health or high stress were more likely to have suicidal ideation. In particular, EQ-5D Index (OR, 5.86; 95% CI, 3.73-9.20), depressive symptoms (OR, 19.65; 95% CI, 9.94-38.83) in 20s, and stress in 80s (OR, 10.87; 95% CI, 5.63-20.96) was the highest, and those had the good subjective health perception in 30s (OR, 0.10; 95% CI, 0.05-0.20) was lowest. Participants in their 30s, 40s, and 60s who were divorced or widowed and those in their 50s and 60s who had never married or lived together were more likely to consider suicide ideation. Except for those in their 20s and 80s, the rate of suicidal ideation tends to increase with lower household income levels. CONCLUSIONS: In the results of this study, it can be seen that a combination of factors such as a person's personality traits, stress or coping ability to various events, social support, and mental or physical limitations influence suicidal behavior. Suicidal ideation is not simply affected by a single factor but may be influenced by multiple factors.

Comparison of Newly Proposed LDL-Cholesterol Estimation Equations.

BACKGROUND: Low-density lipoprotein cholesterol is an important marker highly associated with cardiovascular disease. Since the direct measurement of it is inefficient in terms of cost and time, it is common to estimate through the Friedewald equation developed about 50 years ago. However, various limitations exist since the Friedewald equation was not designed for Koreans. This study proposes a new low-density lipoprotein cholesterol estimation equation for South Koreans using nationally approved statistical data. METHODS: This study used data from the Korean National Health and Nutrition Examination Survey from 2009 to 2019. The 18,837 subjects were used to develop the equation for estimating low-density lipoprotein cholesterol. The subjects included individuals with low-density lipoprotein cholesterol levels directly measured among those with high-density lipoprotein cholesterol, triglycerides, and total cholesterol measured. We compared twelve equations developed in the previous studies and the newly proposed equation (model 1) developed in this study with the actual low-density lipoprotein cholesterol value in various ways. RESULTS: The low-density lipoprotein cholesterol value estimated using the estimation formula and the actual low-density lipoprotein cholesterol value were compared using the root mean squared error. When the triglyceride level was less than 400 mg/dL, the root mean squared of the model 1 was 7.96, the lowest compared to other equations, and the model 2 was 7.82. The degree of misclassification was checked according to the NECP ATP III 6 categories. As a result, the misclassification rate of the model 1 was the lowest at 18.9%, and Weighted Kappa was the highest at 0.919 (0.003), which means it significantly reduced the underestimation rate shown in other existing estimation equations. Root mean square error was also compared according to the change in triglycerides level. As the triglycerides level increased, the root mean square error showed an increasing trend in all equations, but it was confirmed that the model 1 was the lowest compared to other equations. CONCLUSION: The newly proposed low-density lipoprotein cholesterol estimation equation showed significantly improved performance compared to the 12 existing estimation equations. The use of representative samples and external verification is required for more sophisticated estimates in the future.

Randomized, triple-blind, placebo-controlled study to evaluate the safety of 6'-Sialyllactose in healthy adults.

Sialyllactoses (SL) are an abundant component of human milk. There have been many studies on the biological effects of SL in humans. SL can be produced using an economical method of enzyme synthesis. Although the European Food Safety Authority has published the human safety and appropriate intake dose of 6'-SL sodium salt as a novel food, it has suggested that the appropriate dose for particular medical purposes be judged on a case-by-case basis. Also, as revealed in the same report, there are no data on toxicity when 6'-SL is used in human intervention. However, clinical studies have only confirmed the safety of 3'-SL for therapeutic intervention in humans, and the safety for therapeutic use of 6'-SL, which is more abundant than 3'-SL in human milk, has not been confirmed. In this study, to determine the safety of 6'-SL use in humans, participants were randomly assigned to the placebo (maltodextrin) and 6'-SL groups, and then 3 g of powder was orally administered twice a day for 12 weeks. There were no serious adverse reactions, such as life-threatening complications requiring hospitalization, causing disability, or causing deformity during the use of 6'-SL. There were no clinically significant differences among the baseline, sixth, and twelfth week clinical chemistry tests, such as aspartate aminotransferase, alanine aminotransferase, and creatinine. Most of the adverse reactions were gastrointestinal problems such as diarrhea, abdominal discomfort, and bloating, with no significant difference in the proportions between the placebo and 6'-SL groups. These results support the safety of the 6'-SL for human use.

Age- and sex-specific risk of colorectal cancer in incident ulcerative colitis during the first 10 years after diagnosis: a nationwide population-based study.

OBJECTIVE: We assessed the risk of colorectal cancer (CRC) in patients with ulcerative colitis (UC) using the nationwide population-based claims data. MATERIALS AND METHODS: We analyzed the claims data of the Korean National Health Insurance (2006-2015). UC and CRC were defined using ICD-10 codes and UC-specific prescriptions in this study. Age- and sex-matched individuals without UC were randomly selected from the general population. Hazard ratios (HRs), adjusted for different covariates, were calculated using multivariate Cox proportional hazard regression. RESULTS: In total, 30,546 and 88,829 individuals with and without UC, respectively, were enrolled. CRC developed in 85 (0.27%) among UC, and 340 (0.38%) among individuals without UC, respectively. The HR (95% confidence interval [CI]) of CRC in all UC patients was 0.74 (0.58-0.94). Further, UC patients were stratified according to sex (male vs. female: 0.60 [0.44-0.82] vs. 1.10 [0.75-1.61]) and age (HR = 14.37, 2.74, 0.58, and 0.70 for 0-19, 20-39, 40-59, and ≥60 years, respectively). HR was significantly higher for late-onset UC (≥60 years) than for early-onset UC (0-19 years). The long duration of 5-aminosalicylic acid use had a significantly low HR, with reference to the 1st quartile. CONCLUSIONS: The risk of CRC varies with age and sex in Korean patients with UC during the first decade after diagnosis. Early-onset UC (<40 years) increases the CRC risk.

Association between ambient air pollution and high-risk pregnancy: A 2015-2018 national population-based cohort study in Korea.

BACKGROUND: Several studies have indicated that prenatal exposure to ambient air pollution is associated with an increased risk of gestational diabetes mellitus, hypertensive disorder during pregnancy, preterm birth, and stillbirth. However, no previous study has focused on the association between the number of pregnancy complications and exposure to ambient air pollution. OBJECTIVES: To investigate the association between prenatal exposure to ambient air pollutants and the number of pregnancy complications in high-risk pregnancies. METHODS: We collected data on gestational diabetes mellitus, hypertensive disorder during pregnancy, preterm birth, and stillbirth from the National Health Information Databases, provided by the Korean National Health Insurance Service.R To assess individual-level exposure to air pollutants, a spatial prediction model and area-averaging approach were used. RESULTS: From 2015 to 2018, data of 789,595 high-risk pregnancies were analyzed. The ratio of gestational diabetes mellitus in the country was the highest, followed by preterm birth, hypertensive disorder during pregnancy, and stillbirth. Approximately 71.7% of pregnant women (566,143) presented with one pregnancy complication in identical pregnancies, 27.5% (216,714) presented with two, and 0.9% (6738) presented with three or more. Multiple logistic regression models with adjustments for age, residence, and income variables indicated that the risk of having two or more pregnancy complications was positively associated with the exposure to higher levels of PM10 (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.09-1.12) and PM2.5 (OR, 1.14; 95% CI, 1.12-1.15). The highest quartile presented higher odds of two or more pregnancy complications compared with the lower three quartiles of PM10, PM2.5, CO, NO2, and SO2 exposures (p < 0.001). CONCLUSION: The results indicate that the risk of pregnancy complications is positively associated with the exposure to the high concentrations of PM10, PM2.5, CO, NO2, and SO2.

Age and sex dependent association of uric acid and incident hypertension.

BACKGROUND AND AIMS: A previous meta-analysis suggested that the relationship between hyperuricemia and hypertension may be stronger in younger individuals and women. We aimed to investigate the age and sex dependent association of uric acid (UA) and incident hypertension. METHODS AND RESULTS: We analyzed data from the Health Examinees Study, a community-based prospective cohort study conducted in Korea from 2004 to 2013. It included 29,088 non-hypertensive subjects aged 40-79 (age, 52.5 ± 7.8 years; men, 31.4%) who had serum UA measurement and participated in the follow-up survey. The risk factors of hypertension were assessed using Cox regression. Over a mean 3.8 years of follow-up, 1388 men (15.2%) and 1942 women (9.7%) were newly diagnosed with hypertension. Upon age- and sex-based stratification, the risk of hypertension was highest in hyperuricemic subjects aged 40-49 years (HR: women, 2.16; men, 1.30). Across the entire cohort, the risk of incident hypertension was higher in groups with higher serum UA levels, and highest in women aged 40-49 years (HR, 1.44; P < 0.001). On multivariable linear regression analysis, the higher the baseline serum UA level, the greater the increase in blood pressure during follow-up, and this effect was strongest in women aged 40-49 years (ß = 0.87 and P < 0.01 for systolic blood pressure). CONCLUSIONS: The relationship between uric acid and incident hypertension tended to be dependent on age and sex. Younger women are at highest risk of UA-related incident hypertension.

Evaluation of Adherence to Guideline for Heart Failure with Reduced Ejection Fraction in Heart Failure with Preserved Ejection Fraction and with or without Atrial Fibrillation.

BACKGROUND: This study evaluated the relationship between guideline adherence for heart failure (HF) with reduced ejection fraction (HFrEF) at discharge and relevant clinical outcomes in patients with acute HF with preserved ejection fraction (HFpEF) with or without atrial fibrillation (AF). METHODS: We analyzed Korean Acute Heart Failure Registry data for 707 patients with HFpEF with documented AF and 687 without AF. Guideline adherence was defined as good or poor according to the prescription of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, ß-blockers, and mineralocorticoid receptor antagonists. Anticoagulation adherence was also incorporated for the AF group. RESULTS: Among patients with normal sinus rhythm, those with poor guideline adherence had a reduced prevalence of comorbidities and favorable clinical characteristics when compared with those with good guideline adherence. Using inverse probability of treatment weighting (IPTW) to address the bias of nonrandom treatment assignment, good adherence was associated with a poor 60-day composite endpoint in the multivariable Cox model (weighted hazard ratio [wHR], 1.74; 95% confidence interval [CI], 1.01-3.00; P = 0.045). For patients with AF, baseline clinical characteristics were similar according to the degree of adherence. The IPTW-adjusted analysis indicated that good adherence was significantly associated with the 60-day composite endpoint (wHR, 0.47; 95% CI, 0.27-0.79; P = 0.005). In the analysis excluding warfarin, good adherence was associated with 60-day re-hospitalization (wHR, 0.60; 95% CI, 0.37-0.98; P = 0.040), 1-year re-hospitalization (wHR, 0.67; 95% CI, 0.48-0.93; P = 0.018), and the composite endpoint (wHR, 0.77; 95% CI, 0.59-0.99; P = 0.041). CONCLUSION: Our findings indicate that good adherence to guidelines for HFrEF is associated with a better 60-day composite endpoint in patients with HFpEF with AF.

Entropy-Based Graph Clustering of PPI Networks for Predicting Overlapping Functional Modules of Proteins.

Functional modules can be predicted using genome-wide protein-protein interactions (PPIs) from a systematic perspective. Various graph clustering algorithms have been applied to PPI networks for this task. In particular, the detection of overlapping clusters is necessary because a protein is involved in multiple functions under different conditions. graph entropy (GE) is a novel metric to assess the quality of clusters in a large, complex network. In this study, the unweighted and weighted GE algorithm is evaluated to prove the validity of predicting function modules. To measure clustering accuracy, the clustering results are compared to protein complexes and Gene Ontology (GO) annotations as references. We demonstrate that the GE algorithm is more accurate in overlapping clusters than the other competitive methods. Moreover, we confirm the biological feasibility of the proteins that occur most frequently in the set of identified clusters. Finally, novel proteins for the additional annotation of GO terms are revealed.

Fatty liver index and development of cardiovascular disease in Koreans without pre-existing myocardial infarction and ischemic stroke: a large population-based study.

BACKGROUND: Despite the known association between non-alcoholic fatty liver disease (NAFLD) and cardiovascular disease (CVD), whether NAFLD predicts future CVD events, especially CVD mortality, remains uncertain. We evaluated the relationship between fatty liver index (FLI), a validated marker of NAFLD, and risk of major adverse cardiac events (MACEs) in a large population-based study. METHODS: We identified 3011,588 subjects in the Korean National Health Insurance System cohort without a history of CVD who underwent health examinations from 2009 to 2011. The primary endpoint was a composite of cardiovascular deaths, non-fatal myocardial infarction (MI), and ischemic stroke. A Cox proportional hazards regression analysis was performed to assess association between the FLI and the primary endpoint. RESULTS: During the median follow-up period of 6 years, there were 46,010 cases of MACEs (7148 cases of cardiovascular death, 16,574 of non-fatal MI, and 22,288 of ischemic stroke). There was a linear association between higher FLI values and higher incidence of the primary endpoint. In the multivariable models adjusted for factors, such as body weight and cholesterol levels, the hazard ratio for the primary endpoint comparing the highest vs. lowest quartiles of the FLI was 1.99 (95% confidence interval [CIs], 1.91-2.07). The corresponding hazard ratios (95% CIs) for cardiovascular death, non-fetal MI, and ischemic stroke were 1.98 (1.9-2.06), 2.16 (2.01-2.31), and 2.01 (1.90-2.13), respectively (p < 0.001). The results were similar when we performed stratified analyses by age, sex, use of dyslipidemia medication, obesity, diabetes, and hypertension. CONCLUSIONS: Our findings indicate that the FLI, which is a surrogate marker of NAFLD, has prognostic value for detecting individuals at higher risk for cardiovascular events.

Blood pressure levels and cardiovascular risk according to age in patients with diabetes mellitus: a nationwide population-based cohort study.

BACKGROUND: Little is known about age-specific target blood pressure (BP) in hypertensive patients with diabetes mellitus (DM). The aim of this study was to determine the BP level at the lowest cardiovascular risk of hypertensive patients with DM according to age. METHODS: Using the Korean National Health Insurance Service database, we analyzed patients without cardiovascular disease diagnosed with both hypertension and DM from January 2002 to December 2011. Primary end-point was composite cardiovascular events including cardiovascular death, myocardial infarction and stroke. RESULTS: Of 241,148 study patients, 35,396 had cardiovascular events during a median follow-up period of 10 years. At the age of < 70 years, the risk of cardiovascular events was lower in patients with BP < 120/70 mmHg than in those with BP 130-139/80-89 mmHg. At the age of ≥ 70, however, there were no significant differences in the risk of cardiovascular events between patients with BP 130-139/80-89 mmHg and BP < 120/70 mmHg. The risk of cardiovascular events was similar between patients with BP 130-139/80-89 mmHg and BP 120-129/70-79 mmHg, and it was significantly higher in those with BP ≥ 140/90 mmHg than in those with BP 130-139/80-89 mmHg at all ages. CONCLUSIONS: In a cohort of hypertensive patients who had DM but no history of cardiovascular disease, lower BP was associated with lower risk of cardiovascular events especially at the age of < 70. However, low BP < 130-139/80-89 mmHg was not associated with decreased cardiovascular risk, it may be better to keep the BP of 130-139/80-89 mmHg at the age of ≥ 70.

Burden of male hardcore smokers and its characteristics among those eligible for lung cancer screening.

BACKGROUND: There are few data available about hardcore smokers and their behavioral characteristics among the lung cancer screening (LCS) population. The study investigated the burden of hardcore smokers within the LCS population, and determine the characteristics of hardcore smokers using nationally representative data in South Korea. METHODS: We used data from 2007 to 2012 from the Korean National Health and Nutrition Examination Survey. This study enrolled current male smokers aged 55-74 years. Among them, subjects eligible for LCS were defined as these populations with smoking histories of at least 30 PY. Hardcore smoking was defined as smoking >15 cigarettes per day, with no plan to quit, and having made no attempt to quit. Multivariate logistic regression analyses were used to estimate associations between hardcore smokers and various sociodemographic and other variables. RESULTS: The proportion of hardcore smokers among those who met LCS eligibility criteria decreased from 2007 to 2012 (from 39.07 to 29.47% of the population) but did not change significantly thereafter (P = 0.2770), and that proportion was consistently 10-15% higher than that of hardcore smokers among all male current smokers. The proportion without any plan to quit smoking decreased significantly from 54.35% in 2007 to 38.31% in 2012. However, the smokers who had made no intentional quit attempt in the prior year accounted for more than half of those eligible for LCS, and the proportion of such smokers did not change significantly during the study period (50.83% in 2007 and 51.03% in 2012). Multivariate logistic regression analyses showed that hardcore smokers were older (OR = 1.05, 95% confidence interval [CI] 1.01-1.09) than non-hardcore smokers. Hardcore smokers exhibited higher proportion of depression (OR = 6.55, 95% CI 1.75-24.61) and experienced extreme stress more frequently (OR = 1.93, 95% CI 1.13-3.29). Smokers who did not receive smoking cessation education within the past year were significantly more likely to be hardcore smokers (OR = 4.15, 95% CI 1.30-13.22). CONCLUSIONS: It is important to identify a subset of smokers unwilling or minimally motivated to quit within the context of lung cancer screening. Anti-smoking education should be enhanced to influence hardcore smokers' behavior.

Beta-blocker Therapy at Discharge in Patients with Acute Heart Failure and Atrial Fibrillation.

BACKGROUND: ß-blockers (BBs) are considered primary therapy in stable heart failure (HF) with reduced ejection fraction (HFrEF) without atrial fibrillation (AF); evidence-based benefits of BB on outcome have been documented. However, BBs have not been shown to improve mortality or reduce hospital admissions in HF patients with AF. This study assessed the relationship between BBs at discharge and relevant clinical outcomes in acute heart failure (AHF) patients with AF. METHODS: From the Korean Acute Heart Failure Registry, 936 HFrEF and 639 HF patients with preserved ejection fraction (HFpEF) and AF were selected. Propensity score (PS) matching accounted for BB selection bias when assessing associations. RESULTS: BB-untreated patients in the overall cohort of HFrEF and HFpEF had greater deteriorated clinical and laboratory characteristics. In the 670 PS-matched cohort of HFrEF patients, incidences of all clinical events at 60 days and 1 year were not different according to use of BBs. In the 470 PS-matched cohort of HFpEF, rehospitalization and composite outcome at 6 months and 1 year more frequently occurred in non-users of BBs. After adjusting for covariates in the multivariable Cox model of matched cohorts, BB was not associated with clinical outcomes at 60 days and 1 year in HFrEF with AF patients. In HFpEF patients with AF, BB use was associated with reduced 6-month (hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.20-0.74) and 1-year rehospitalization (HR, 0.53; 95% CI, 0.34-0.82). CONCLUSION: In the HFrEF with AF PS-matched cohort, the use of BBs at discharge was not associated with clinical outcome. However, in HFpEF with AF, the use of BB was associated with reduced rehospitalization during the 6-month and 1-year follow up.

Long-term Effects of Cumulative Average PM2.5 Exposure on the Risk of Hemorrhagic Stroke.

BACKGROUND: Epidemiological studies have revealed associations between the fine particle (PM2.5; aerodynamic diameter <2.5 µm) exposure and cardiovascular disease. Researchers have also recently begun investigating the association between PM2.5 exposure and hemorrhagic stroke (HS) and identifying subpopulations vulnerable to PM2.5 exposure. Long-term cumulative average PM2.5 exposure may affect the risk of HS, and these effects may be modified by risk factors. METHODS: This retrospective study evaluated the effects of PM2.5 on the time-to-first-diagnosis of HS among 62,676 Seoul metropolitan city residents with 670,431 total person-years of follow-up; this cohort is a subset from a nationally representative cohort of 1,025,340 individuals from the Korean National Health Insurance Service database (2002-2013). A time-dependent Cox proportional hazards model was used to adjust for age, sex, household income, insurance type, body mass index, smoking status, medical history, and family history. The annual mean PM2.5 concentrations for 25 districts were used as the time-dependent variable. Subgroup analyses of the traditional risk factors of HS were performed to evaluate potential effect modifications. RESULTS: Each 10-µg/m increment in cumulative average PM2.5 exposure was noticeably associated with HS (hazard ratio [HR] = 1.43; 95% confidence interval [CI]: 1.09-1.88). The adverse effects of PM2.5 exposure were modified by ≥65 years of age (HR = 2.00; 95% CI = 1.32, 3.02) and obesity (body mass index ≥25 kg/m; HR = 1.91; 95% CI = 1.28, 2.84). CONCLUSIONS: Cumulative average PM2.5 exposure might increase the risk of HS. Elderly (≥65 years) and obese individuals may be more vulnerable to the effects of PM2.5 exposure.