GraphMHC: Neoantigen prediction model applying the graph neural network to molecular structure.

Neoantigens are tumor-derived peptides and are biomarkers that can predict prognosis related to immune checkpoint inhibition by estimating their binding to major histocompatibility complex (MHC) proteins. Although deep neural networks have been primarily used for these prediction models, it is difficult to interpret the models reported thus far as accurately representing the interactions between biomolecules. In this study, we propose the GraphMHC model, which utilizes a graph neural network model applied to molecular structure to simulate the binding between MHC proteins and peptide sequences. Amino acid sequences sourced from the immune epitope database (IEDB) undergo conversion into molecular structures. Subsequently, atomic intrinsic informations and inter-atomic connections are extracted and structured as a graph representation. Stacked graph attention and convolution layers comprise the GraphMHC network which classifies bindings. The prediction results from the test set using the GraphMHC model showed a high performance with an area under the receiver operating characteristic curve of 92.2% (91.9-92.5%), surpassing a baseline model. Moreover, by applying the GraphMHC model to melanoma patient data from The Cancer Genome Atlas project, we found a borderline difference (0.061) in overall survival and a significant difference in stromal score between the high and low neoantigen load groups. This distinction was not present in the baseline model. This study presents the first feature-intrinsic method based on biochemical molecular structure for modeling the binding between MHC protein sequences and neoantigen candidate peptide sequences. This model can provide highly accurate responsibility information that can predict the prognosis of immune checkpoint inhibitors to cancer patients who want to apply it.

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.

Efficacy and Safety of High Density LED Irradiation Therapy for Patients With Hand Osteoarthritis: A Single-Center Clinical Study.

OBJECTIVE: To assess the safety and effectiveness of high-density light-emitting diode (LED) irradiation therapy in patients with hand osteoarthritis (OA) and compare the pre- and post-intervention symptoms. METHODS: Twenty-three patients with hand OA underwent eight sessions of high-density LED irradiation therapy directed at the five most painful areas in the finger joints. Each session lasted for 18 minutes; and the sessions were conducted twice a week, for 4 weeks. We evaluated the degree of pain using the visual analogue scale, ring size, and passive range of motion (flexion+extension) for two most painful joints from the baseline to post-therapy (weeks 4 and 6). RESULTS: High-density LED irradiation therapy significantly reduced the pain posttreatment compared with that observed at the baseline (p<0.001). Although improvements were observed in ring size and joint range of motion at 4 and 6 weeks, they were not statistically significant (p>0.05). No adverse events were observed. CONCLUSION: We examined the safety and effectiveness of high-density LED irradiation therapy in reducing pain and hand swelling and improving joint mobility in patients with hand OA. These results suggest that high-density LED irradiation therapy has the potential to be an important strategy for managing hand OA.

Repeated measurements and mixture effects of urinary bisphenols, parabens, polycyclic aromatic hydrocarbons, and other chemicals on biomarkers of oxidative stress in pre- and postpartum women.

The association between oxidative stress and exposure to bisphenols, parabens, phenols, polycyclic aromatic hydrocarbons (PAH), and volatile organic compounds (VOCs) has been investigated by many in vitro and in vivo studies. However, most of these findings are based on cross-sectional studies, as a result of which the combined effects of these compounds have been rarely analyzed. In this study, our objective was to assess urinary bisphenols, parabens, PAHs, and VOCs, in relation to oxidative stress during pre-and postpartum periods, analyze the association between these chemicals and oxidative stress via repeated measurements using a linear mixed model (LMM), and evaluate the combined effects exerted by these chemicals on oxidative stress using Bayesian Kernel Machine Regression (BKMR). A total 529 urine samples were collected from 242 pregnant women during the 1st and 2nd trimesters, as well as postpartum follow-ups. Three bisphenols, four parabens, benzopheone-3 (BP-3), triclosan (TCS), four PAHs, two VOCs, and 3- phenoxy-benzoic acid (3-PBA) were analyzed. We also measured 8-hydroxydeoxyguanosine (8-OHdG) and malondialdehyde (MDA), which serve as oxidative stress biomarkers in maternal urine samples. During this period, 8-OHdG decreased steadily, whereas MDA increased during pregnancy and decreased after childbirth. LMM indicated that Bisphenol A, Prophyl-paraben, BP-3, and 1-hydroxypyrene (1-OHP) showed a significant association with increased MDA levels. The BKMR models revealed that the mixture effect exerted by these 16 chemicals had changed MDA levels, which indicate oxidative stress, and that both Butyl Paraben (BP) and 1-hydroxypyrene (1-OHP) had contributed to such oxidative stress. Mixtures of each subgroup (bisphenols, parabens, and PAHs) were associated with increased MDA levels. These findings suggest that exposure to some phenols and PAHs during pre- and post-partum stages may cause oxidative stress, and that exposure to these chemicals should be minimized during this period.

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.

Gout and the Prevalence of Dementia: A Nationwide Population-Based Study.

BACKGROUND: Hyperuricemia in patients with gout is associated with a low risk of neurodegenerative diseases, including dementia. However, the prevalence of dementia in patients with gout has not yet been reported. OBJECTIVE: To analyze the prevalence of dementia among patients diagnosed with gout by utilizing the Health Insurance and Review Assessment database, a nationwide registry of the South Korean population. METHODS: Data from the Health Insurance and Review Assessment database of patients diagnosed with gout between 2011 and 2018 were extracted. The annual prevalence of dementia according to age and sex was analyzed. We investigated whether there was an association between comorbidities and gout medication in patients with both gout and dementia and in patients with only gout. RESULTS: Between 2011 and 2018, the age-adjusted prevalence of dementia per 100,000 persons ranged from 54.0 (95% confidence interval: 47.7-60.2) to 69.9 (95% confidence interval: 65.3-74.5). Compared to previous studies, the prevalence of dementia was lower in patients with gout than in the general population. Patients with both gout and dementia were more likely to be women, have a wide range of comorbidities, and be prescribed gout-related drugs, including allopurinol, febuxostat, nonsteroidal anti-inflammatory drugs, and steroids than patients with gout without dementia. CONCLUSIONS: This study demonstrated a relatively low prevalence of dementia in patients with gout. Gout, characterized by hyperuricemia, might be associated with a reduced risk of dementia.

Risk Factors for Lower Extremity Amputation in Patients with End-Stage Kidney Disease: A Nationwide Cohort Study.

Individuals with end-stage kidney disease (ESKD) on dialysis are at a high risk of developing foot ulcerations and undergoing subsequent lower extremity amputation (LEA), which can exert significant impacts on their quality of life and contribute to rising healthcare costs. We aimed to identify risk factors associated with LEA in patients with ESKD to predict LEA progression and eventually prevent it. We used 18 years (2002-2019) of data from the Korean National Health Insurance Service (KNHIS). Data were collected from patients with ESKD who underwent renal replacement therapy (RRT) and had no history of amputation caused by trauma or toxins. The risk factors were compared between patients with or without LEA. We collected data from 220,838 patients newly diagnosed with ESKD, including 6348 in the LEA group and 214,490 in the non-LEA group. The total incidence of LEA was 2.9%. Older age, male gender, lower income, non-metropolitan residence, diabetes mellitus, dialysis treatment (compared to kidney transplantation), microvascular disease, peripheral vascular disease, endovascular procedure, and endovascular operation were associated with an increased risk of LEA. Thus, individuals with ESKD who are at a higher risk for LEA should be closely monitored, and kidney transplantation should be considered as a preventative measure.

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.

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.

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.

Hemostatic efficacy of a flowable collagen-thrombin matrix during coronary artery bypass grafting: a double-blind randomized controlled trial.

BACKGROUND: Flowable hemostatic agents have the advantage of being able to be applied to irregular wound surfaces and difficult to reach areas. We sought to compare the effectiveness and safety of the flowable hemostatic sealants Collastat® (collagen hemostatic matrix, [CHM]) and Floseal® (gelatin hemostatic matrix, [GHM]) during off-pump coronary artery bypass (OPCAB). METHODS: In this prospective, double-blind, randomized controlled trial, 160 patients undergoing elective OPCAB surgery were enrolled between March 2018 and February 2020. After primary suture of the aortocoronary anastomosis, an area of hemorrhage was identified, and patients received either CHM or GHM (n = 80, each). Study endpoints were the following: proportion of successful intraoperative hemostasis and time required for hemostasis overall postoperative bleeding, proportion of transfusion of blood products, and surgical revision for bleeding. RESULTS: Of the total patients, 23% were female, and the mean age was 63 years (range 42-81 years). Successful hemostasis proportion within 5 min was achieved for 78 patients (97.5%) in the GHM group, compared to 80 patients (100%) in the CHM group (non-inferiority p = 0.006). Two patients receiving GHM required surgical revision to achieve hemostasis. There were no differences in the mean time required to obtain hemostasis [GHM vs. CHM, mean 1.49 (SD 0.94) vs. 1.35 (0.60) min, p = 0.272], as confirmed by time-to-event analysis (p = 0.605). The two groups had similar amounts of mediastinal drainage for 24 h postoperatively [538.5 (229.1) vs. 494.7 (190.0) ml, p = 0.298]. The CHM group required less packed red blood cells, fresh frozen plasma, and platelets for transfusion than the GHM group (0.5 vs. 0.7 units per patient, p = 0.047; 17.5% vs. 25.0%, p = 0.034; 7.5% vs. 15.0%, p = 0.032; respectively). CONCLUSIONS: CHM was associated with a lower need for FFP and platelet transfusions. Thus, CHM is a safe and effective alternative to GHM. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04310150.

Factors Predicting Older People's Acceptance of a Personalized Health Care Service App and the Effect of Chronic Disease: Cross-Sectional Questionnaire Study.

BACKGROUND: Mobile health (mHealth) services enable real-time measurement of information on individuals' biosignals and environmental risk factors; accordingly, research on health management using mHealth is being actively conducted. OBJECTIVE: The study aims to identify the predictors of older people's intention to use mHealth in South Korea and verify whether chronic disease moderates the effect of the identified predictors on behavioral intentions. METHODS: A cross-sectional questionnaire study was conducted among 500 participants aged 60 to 75 years. The research hypotheses were tested using structural equation modeling, and indirect effects were verified through bootstrapping. Bootstrapping was performed 10,000 times, and the significance of the indirect effects was confirmed through the bias-corrected percentile method. RESULTS: Of 477 participants, 278 (58.3%) had at least 1 chronic disease. Performance expectancy (ß=.453; P=.003) and social influence (ß=.693; P<.001) were significant predictors of behavioral intention. Bootstrapping results showed that facilitating conditions (ß=.325; P=.006; 95% CI 0.115-0.759) were found to have a significant indirect effect on behavioral intention. Multigroup structural equation modeling testing the presence or absence of chronic disease revealed a significant difference in the path of device trust to performance expectancy (critical ratio=-2.165). Bootstrapping also confirmed that device trust (ß=.122; P=.039; 95% CI 0.007-0.346) had a significant indirect effect on behavioral intention in people with chronic disease. CONCLUSIONS: This study, which explored the predictors of the intention to use mHealth through a web-based survey of older people, suggests similar results to those of other studies that applied the unified theory of acceptance and use of technology model to the acceptance of mHealth. Performance expectancy, social influence, and facilitating conditions were revealed as predictors of accepting mHealth. In addition, trust in a wearable device for measuring biosignals was investigated as an additional predictor in people with chronic disease. This suggests that different strategies are needed, depending on the characteristics of users.

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.

Elevated risk of cervical cancer in elderly women with incident ulcerative colitis in South Korea.

The association between ulcerative colitis (UC) and uterine cervical cancer is still unclear. To investigate cervical cancer risk in South Korean women with UC, we analyzed the Korean National Health Insurance claims data. UC was defined using both ICD-10 codes and UC-specific prescriptions. We analyzed incident cases of UC diagnosed between 2006 and 2015. Age-matched women without UC (control group) were randomly selected from the general population (1:3 ratio). Hazard ratios were calculated using multivariate Cox proportional hazard regression, and the event was defined as occurrence of cervical cancer. A total of 12,632 women with UC and 36,797 women without UC were enrolled. The incidence of cervical cancer was 38.8 per 100,000 women per year in UC patients and 25.7 per 100,000 women per year in controls, respectively. The adjusted HR for cervical cancer was 1.56 (95% CI 0.97-2.50) in the UC group with reference to the control group. When stratified by age, the adjusted HR for cervical cancer was 3.65 (95% CI 1.54-8.66) in elderly UC patients (≥ 60 years) compared to elderly control group (≥ 60 years). Within UC patients, increased age (≥ 40 years) and low socioeconomic status were associated with an increased risk of cervical cancer. The incidence of cervical cancer was found to be higher among elderly patients (≥ 60 years) with newly diagnosed UC in South Korea, compared to age-matched controls. Therefore, regular cervical cancer screening is recommended for elderly patients who have recently been diagnosed with UC.

Risk of Gastric Cancer among Patients with Newly Diagnosed Ulcerative Colitis: A Nationwide Population-Based Study.

BACKGROUND: Few studies have investigated the risk of gastric cancer (GC) in ulcerative colitis (UC), and the results have been inconsistent. This study aimed to assess the risk of gastric cancer in newly diagnosed UC patients. METHODS: Based on claims data from Korean National Health Insurance from January 2006 to December 2015, we identified 30,546 patients with UC and randomly selected 88,829 non-UC individuals as controls, who were matched by age and sex. Multivariate Cox proportional hazards regression was used to calculate adjusted hazard ratios (HRs) for gastric cancer events, with covariates taken into account. RESULTS: During the study period, a total of 77 (0.25%) patients with UC and 383 (0.43%) non-UC individuals were diagnosed with GC. After multivariable adjustment, the HR for GC was 0.60 (95% CI: 0.47-0.77) in patients with UC, using non-UC individuals as the reference group. When stratified by age, the adjusted HRs for GC in UC patients were 0.19 (95% CI: 0.04-0.98) for those aged 20-39 years at the time of UC diagnosis, 0.65 (95% CI: 0.45-0.94) for 40-59, and 0.60 (95% CI: 0.49-0.80) for ≥60 as compared to non-UC individuals in the corresponding age groups. When stratified by sex, the adjusted HR for GC was 0.54 (95% CI: 0.41-0.73) in male UC patients of all ages. Within UC patients, a multivariable analysis revealed that the HR for GC was 12.34 (95% CI: 2.23-68.16) for those aged ≥ 60 years at the time of diagnosis of UC. CONCLUSIONS: Patients with UC had a decreased GC risk compared with non-UC individuals in South Korea. Within the UC population, advancing age (≥60 years) was identified as a significant risk factor for GC.

Association between smoking and all-cause mortality in Parkinson's disease.

We aimed to investigate the association between smoking status and all-cause mortality of Parkinson's disease (PD). Among the whole nationwide population data from Korea National Health Insurance Service, newly diagnosed PD was selected, and all-cause mortality was evaluated. The systematic review was performed through a literature search on the PubMed, EMBASE, and Cochrane Central Register of Controlled Trials databases. Among 26,080 individuals with PD, there was no significant association between smoking status and all-cause mortality in a nationwide cohort study (ex-smoker, HR 0.1.03, 95% CI 0.97-1.10; current smoker, HR 1.06, 95% CI 0.96-1.16). The systematic review, including six prospective cohort studies, also found a nonsignificant association. PD smokers tended to have fewer deaths from neurologic causes but were significantly more likely to die from smoking-related cancers such as lung cancer. We presented a nonsignificant association between smoking and mortality of PD, and cigarette smoking is not recommended in individuals with PD.

Evaluation of an air quality warning system for vulnerable and susceptible individuals in Korea: an interrupted time series analysis.

OBJECTIVES: This study was conducted to elucidate the effects of an air quality warning system (AQWS) implemented in January 2015 in Korea by analyzing changes in the incidence and exacerbation rates of environmental diseases. METHODS: Data from patients with environmental diseases were extracted from the National Health Insurance Service-National Sample Cohort database from 2010 to 2019, and data on environmental risk factors were acquired from the AirKorea database. Patient and meteorological data were linked based on residential area. An interrupted time series analysis with Poisson segmented regression was used to compare the rates before and after AQWS introduction. Adjustment variables included seasonality, air pollutants (carbon monoxide, nitrogen dioxide, sulfur dioxide, particulate matter less than 10 µm in diameter, and ozone), temperature, and humidity. RESULTS: After AQWS implementation, the incidence of asthma gradually decreased by 20.5%. Cardiovascular disease and stroke incidence also significantly decreased (by 34.3 and 43.0%, respectively). However, no immediate or gradual decrease was identified in the exacerbation rate of any environmental disease after AQWS implementation. Sensitivity analyses were performed according to age, disability, and health insurance coverage type. Overall, the AQWS effectively mitigated the occurrence of most environmental diseases in Korea. However, the relationships between alarm system implementation and reduced incidence differed among diseases based on the characteristics of vulnerable and sensitive individuals. CONCLUSIONS: Our results suggest that by tailoring the AQWS to demographic and sociological characteristics and providing enhanced education about the warning system, interventions can become an efficient policy tool to decrease air pollution- related health risks.

Remnant cholesterol, low-density lipoprotein cholesterol, and incident cardiovascular disease among Koreans: a national population-based study.

AIMS: The synergistic association of remnant cholesterol (remnant-C) and low-density lipoprotein cholesterol (LDL-C) levels with incident cardiovascular disease (CVD) in various subgroups of Koreans was investigated. METHODS AND RESULTS: Using the national health insurance data, we included subjects aged between 40 and 70 years without a history of CVD and at least two health screenings between 2009 and 2011. The subjects were divided into four groups by LDL-C and remnant-C levels. The primary outcome was CVD, which occurred between 2014 and 2017. Among 3 686 034 (45.6% women) subjects, 144 004 cardiovascular events occurred. Individuals in both high LDL-C and high remnant-C [hazard ratio (HR) 1.266, 95% confidence interval (CI) 1.243-1.289; 7.9%], high LDL-C only (HR 1.098, 95% CI 1.083-1.113; 21.2%), and high remnant-C only groups (HR 1.102, 95% CI 1.087-1.118; 19.1%) had higher risks of CVD than those in the reference group (LDL-C < 3.4 mmol/L and remnant-C < 0.8 mmol/L; 51.8%). A continuous and linear increase in CVD risk was found in those with higher remnant-C levels after adjustment for several confounders, including LDL-C levels. The association of remnant-C ≥ 0.8 mmol/L with an increased CVD risk was consistent across various strata. CONCLUSIONS: Combined high remnant-C and LDL-C levels confer a higher CVD risk than that individually. Elevated remnant-C values independent of LDL-C levels were associated with a risk of incident CVD. Remnant cholesterol levels in addition to LDL-C levels are important considerations in risk stratification for the primary prevention of CVD.

Since remnant-C has recently emerged as a potential risk factor for CVD, the synergistic association of LDL-C and remnant-C with CVD has been investigated among 3 686 034 Koreans (45.6% women) without preceding CVD using nationwide population-based big data. Remnant cholesterol remained proportional to the risk of incident CVD after adjusting for multiple variables, including LDL-C levels.Low-density lipoprotein cholesterol and remnant-C synergistically contributed to incident CVD.

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.