Table S1. Sensitivity analysis of the association between continuity of care and ESRD incidence (... more Table S1. Sensitivity analysis of the association between continuity of care and ESRD incidence (including deaths). (DOC 31 kb)
Several studies have shown that the use of sulfonylureas in patients with type 2 diabetes mellitu... more Several studies have shown that the use of sulfonylureas in patients with type 2 diabetes mellitus (T2DM) is associated with a higher risk of hepatocellular carcinoma (HCC). In this study, we investigated the effects of individual sulfonylureas on HCC development using the National Health Insurance Service-National Sample Cohort in South Korea. Among 47,738 subjects aged 40 years or older who had newly diagnosed with diabetes, 241 incident HCC cases and 1205 matched controls were identified. Adjusted odds ratios (ORs) as estimates of the relative risk of HCC were calculated using logistic regression analysis. Compared to patients never treated with a sulfonylurea, those treated with a sulfonylurea had a 1.7-fold increased risk of HCC development. Of the different types of sulfonylureas, the exclusive use of glimepiride was associated with a significantly elevated risk of HCC (OR = 1.89, 95% CI = 1.02–3.47) compared to those who were never treated with sulfonylureas. No significant a...
International Journal of Environmental Research and Public Health, 2019
We aimed to use deep learning to detect tuberculosis in chest radiographs in annual workers’ heal... more We aimed to use deep learning to detect tuberculosis in chest radiographs in annual workers’ health examination data and compare the performances of convolutional neural networks (CNNs) based on images only (I-CNN) and CNNs including demographic variables (D-CNN). The I-CNN and D-CNN models were trained on 1000 chest X-ray images, both positive and negative, for tuberculosis. Feature extraction was conducted using VGG19, InceptionV3, ResNet50, DenseNet121, and InceptionResNetV2. Age, weight, height, and gender were recorded as demographic variables. The area under the receiver operating characteristic (ROC) curve (AUC) was calculated for model comparison. The AUC values of the D-CNN models were greater than that of I-CNN. The AUC values for VGG19 increased by 0.0144 (0.957 to 0.9714) in the training set, and by 0.0138 (0.9075 to 0.9213) in the test set (both p < 0.05). The D-CNN models show greater sensitivity than I-CNN models (0.815 vs. 0.775, respectively) at the same cut-off ...
International journal for equity in health, Jan 8, 2016
Previous studies have shown that contextual factors and individual socioeconomic status (SES) wer... more Previous studies have shown that contextual factors and individual socioeconomic status (SES) were associated with mortality in Western developed countries. In Korea, there are few empirical studies that have evaluated the association between SES and health outcomes. We conducted cohort study to investigate the socioeconomic disparity in all-cause mortality for patients newly diagnosed with hypertension in the setting of universal health care coverage. We used stratified random sample of Korean National Health Insurance enrollees (2002-2013). We included patients newly diagnosed with hypertension (n = 28,306) from 2003-2006, who received oral medication to control their hypertension. We generated a frailty model using Cox's proportional hazard regression to assess risk factors for mortality. A total of 7,825 (27.6%) of the 28,306 eligible subjects died during the study period. Compared to high income patients from advantaged neighborhoods, the adjusted hazard ratio (HR) for high...
Liver international : official journal of the International Association for the Study of the Liver, Nov 14, 2015
Analyzing the mutation pattern of multi-drug resistance(MDR) is important in the treatment of chr... more Analyzing the mutation pattern of multi-drug resistance(MDR) is important in the treatment of chronic hepatitis B(CHB). In this study, the evolutionary pattern of MDR mutations was investigated in patients receiving entecavir (ETV) rescue therapy. Eight CHB patients with lamivudine(LAM)-and adefovir(ADV)-resistant mutations showing suboptimal response to ETV and to subsequent ETV-plus-ADV therapy were enrolled. The clonal evolution of the mutation pattern was investigated through direct sequencing, multiplex restriction fragment mass polymorphism(RFMP), and clonal analysis, and the utility of these methods was compared. Among 160 clones at baseline, wild-type hepatitis B virus(HBV) was present in 62(38.8%), LAM-resistant mutations in 92(57.6%), and ADV-resistant mutations in 55(34.4%). LAM-resistant mutations increased to 70.6% at the end of ETV therapy and increased to 74.4% at the 12(th) month of ETV-plus-ADV therapy. During the same time periods, ETV-resistant mutations were pres...
It is not yet clear whether Glutathione S-transferase M1 (GSTM1) polymorphisms affect the risk of... more It is not yet clear whether Glutathione S-transferase M1 (GSTM1) polymorphisms affect the risk of breast cancer. The aim of this study is to provide a comprehensive meta-analysis of all the available, published case-control studies on the extent of the possible association between GSTM1 polymorphisms and susceptibility to breast cancer. Twenty case-control studies on GSTM1 and breast cancer were identified using both PUBMED and a manual search. Meta-analysis was conducted by the Peto method. Subgroup analyses were undertaken, in order to explore the relationship between effect sizes and the study characteristics. The overall odds ratio (OR) was found to be 1.06 (95% CI, 0.99-1.14). The OR for post-menopausal women with GSTM1 deficiency was determined to be 1.19 (95% CI, 1.05-1.34). In populations with a low frequency of GSTM1 deficiency, a greater increase was observed (OR, 1.20; 95% CI, 1.08-1.34). Furthermore, the highest associations were found in post-menopausal women with a low...
Journal of preventive medicine and public health = Yebang Ŭihakhoe chi, 2006
This study was to investigate if the dipstick proteinuria can predict cardiovascular mortality in... more This study was to investigate if the dipstick proteinuria can predict cardiovascular mortality in a population of Korean men. We measured urine protein and other cardiovascular risk factors in 100,059 Korean men, aged between 35-59 years in 1990 and 1992. Levels of proteinuria measured by dipstick method were trace or less, 1+, 2+, and 3+ or greater. The primary outcomes were deaths from all causes, cardiovascular disease, cancer, and others in a 12 year follow-up from 1993 to 2004. The multivariate-adjusted relative risks (95% CI) for cardiovascular death according to the level of proteinuria (1+, 2+, 3+ and more) in 1990 examination were 2.18 (1.36-3.48), 2.55 (1.37-4.78), and 4.57 (2.16-9.66) respectively. The corresponding relative risks according to the level of proteinuria in 1992 examination were 2.49 (1.71-3.64), 2.64 (1.53-4.58), and 2.78 (1.15-6.73). The relative risks for cardiovascular death of men with proteinuria (1+ or greater) once and twice among the examinations we...
To propose an efficient screening schedule for breast cancer among Korean women using the stochas... more To propose an efficient screening schedule for breast cancer among Korean women using the stochastic model in which the age-specific incidence rate was considered. Female breast cancer data in the Korea Central Cancer Registry 2002. The stochastic model was based on the threshold method, in which the schedule is determined by a pre-specified threshold value. The threshold value was defined as the probability of being in a preclinical state of breast cancer at age 40 years. The sensitivity of the mammography was specified as 0.7. Two models for mean sojourn time (MST) in the preclinical state were considered; MSTs for Model I were 2 (ages < 50 years), 3 (ages 50-59 years), and 4 years (ages > or = 60 years), and MSTs for Model II were 3, 4, and 5 years for the corresponding age groups. The threshold method for Model I generated 19 examinations within the screening ages of 40-69 years. Each screening time was determined at ages 40.0, 41.6, 43.2, 44.8, 46.0, 47.2, 48.4, 49.6, 50....
SummaryThe degree of thrombus resolution directly indicates the effectiveness of a thrombolytic d... more SummaryThe degree of thrombus resolution directly indicates the effectiveness of a thrombolytic drug. We investigated the degree of thrombus resolution and factors associated with thrombus resolution after intravenous (IV) recombinant tissue plasminogen activator (rt-PA) using thin-section noncontrast computed tomography (NCT). Thin-section NCTs were performed before and immediately after IV rt-PA infusion in acute stroke patients. The thrombus volume and Hounsfield unit were measured using three-dimensional imaging software. Immediate recanalisation was assessed immediately after IV rt-PA infusion using CT angiography. During a three-year study period, 130 patients were prospectively enrolled. On baseline thin-section NCT, no thrombi were found in 30 patients (23%). Among the 100 patients with confirmed thrombus, the median volume decreased by 20% on the follow-up NCT. The thrombus was completely resolved in 8%. Of note, an increase in thrombus volume was observed in 20 patients. I...
Frameshift mutation at coding mononucleotide repeat sequences are common in tumors with microsate... more Frameshift mutation at coding mononucleotide repeat sequences are common in tumors with microsatellite instability (MSI-H), but the incidences are different among the target genes. We analyzed the mutational profiles of 12 known target genes containing polydeoxyadenosine repeats in their coding sequences in 39 MSI-H colorectal carcinomas and 40 MSI-H gastric carcinomas by using polymerase chain reaction and sequencing, and compared the results with the clinicopathologic characteristics. Frameshift mutations of target genes in the MSI-H colorectal and gastric carcinomas are increased according to the length of the polydeoxyadenosine repeats in the target genes. The mean mutational rates of MSI-H colorectal carcinomas and MSI-H gastric carcinomas were 2.03 and 1.95 in the 4 genes containing (A)10 repeats, 1.23 and 0.73 in the 4 genes with (A)9 repeats and 0.61 and 0.48 in the 4 genes containing (A)8 repeats, respectively (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Among the evaluated clinicopathologic findings, intestinal type gastric carcinomas had more frameshift mutations than the diffuse type carcinomas (3.5 vs. 1.9, p=0.01). These findings suggest that mutational rates of the target genes in MSI-H tumors are diverse, and higher mutational rates are related to the length of mononucleotide repeat sequences of the target genes and histologic type of tumors.
Table S1. Sensitivity analysis of the association between continuity of care and ESRD incidence (... more Table S1. Sensitivity analysis of the association between continuity of care and ESRD incidence (including deaths). (DOC 31 kb)
Several studies have shown that the use of sulfonylureas in patients with type 2 diabetes mellitu... more Several studies have shown that the use of sulfonylureas in patients with type 2 diabetes mellitus (T2DM) is associated with a higher risk of hepatocellular carcinoma (HCC). In this study, we investigated the effects of individual sulfonylureas on HCC development using the National Health Insurance Service-National Sample Cohort in South Korea. Among 47,738 subjects aged 40 years or older who had newly diagnosed with diabetes, 241 incident HCC cases and 1205 matched controls were identified. Adjusted odds ratios (ORs) as estimates of the relative risk of HCC were calculated using logistic regression analysis. Compared to patients never treated with a sulfonylurea, those treated with a sulfonylurea had a 1.7-fold increased risk of HCC development. Of the different types of sulfonylureas, the exclusive use of glimepiride was associated with a significantly elevated risk of HCC (OR = 1.89, 95% CI = 1.02–3.47) compared to those who were never treated with sulfonylureas. No significant a...
International Journal of Environmental Research and Public Health, 2019
We aimed to use deep learning to detect tuberculosis in chest radiographs in annual workers’ heal... more We aimed to use deep learning to detect tuberculosis in chest radiographs in annual workers’ health examination data and compare the performances of convolutional neural networks (CNNs) based on images only (I-CNN) and CNNs including demographic variables (D-CNN). The I-CNN and D-CNN models were trained on 1000 chest X-ray images, both positive and negative, for tuberculosis. Feature extraction was conducted using VGG19, InceptionV3, ResNet50, DenseNet121, and InceptionResNetV2. Age, weight, height, and gender were recorded as demographic variables. The area under the receiver operating characteristic (ROC) curve (AUC) was calculated for model comparison. The AUC values of the D-CNN models were greater than that of I-CNN. The AUC values for VGG19 increased by 0.0144 (0.957 to 0.9714) in the training set, and by 0.0138 (0.9075 to 0.9213) in the test set (both p < 0.05). The D-CNN models show greater sensitivity than I-CNN models (0.815 vs. 0.775, respectively) at the same cut-off ...
International journal for equity in health, Jan 8, 2016
Previous studies have shown that contextual factors and individual socioeconomic status (SES) wer... more Previous studies have shown that contextual factors and individual socioeconomic status (SES) were associated with mortality in Western developed countries. In Korea, there are few empirical studies that have evaluated the association between SES and health outcomes. We conducted cohort study to investigate the socioeconomic disparity in all-cause mortality for patients newly diagnosed with hypertension in the setting of universal health care coverage. We used stratified random sample of Korean National Health Insurance enrollees (2002-2013). We included patients newly diagnosed with hypertension (n = 28,306) from 2003-2006, who received oral medication to control their hypertension. We generated a frailty model using Cox's proportional hazard regression to assess risk factors for mortality. A total of 7,825 (27.6%) of the 28,306 eligible subjects died during the study period. Compared to high income patients from advantaged neighborhoods, the adjusted hazard ratio (HR) for high...
Liver international : official journal of the International Association for the Study of the Liver, Nov 14, 2015
Analyzing the mutation pattern of multi-drug resistance(MDR) is important in the treatment of chr... more Analyzing the mutation pattern of multi-drug resistance(MDR) is important in the treatment of chronic hepatitis B(CHB). In this study, the evolutionary pattern of MDR mutations was investigated in patients receiving entecavir (ETV) rescue therapy. Eight CHB patients with lamivudine(LAM)-and adefovir(ADV)-resistant mutations showing suboptimal response to ETV and to subsequent ETV-plus-ADV therapy were enrolled. The clonal evolution of the mutation pattern was investigated through direct sequencing, multiplex restriction fragment mass polymorphism(RFMP), and clonal analysis, and the utility of these methods was compared. Among 160 clones at baseline, wild-type hepatitis B virus(HBV) was present in 62(38.8%), LAM-resistant mutations in 92(57.6%), and ADV-resistant mutations in 55(34.4%). LAM-resistant mutations increased to 70.6% at the end of ETV therapy and increased to 74.4% at the 12(th) month of ETV-plus-ADV therapy. During the same time periods, ETV-resistant mutations were pres...
It is not yet clear whether Glutathione S-transferase M1 (GSTM1) polymorphisms affect the risk of... more It is not yet clear whether Glutathione S-transferase M1 (GSTM1) polymorphisms affect the risk of breast cancer. The aim of this study is to provide a comprehensive meta-analysis of all the available, published case-control studies on the extent of the possible association between GSTM1 polymorphisms and susceptibility to breast cancer. Twenty case-control studies on GSTM1 and breast cancer were identified using both PUBMED and a manual search. Meta-analysis was conducted by the Peto method. Subgroup analyses were undertaken, in order to explore the relationship between effect sizes and the study characteristics. The overall odds ratio (OR) was found to be 1.06 (95% CI, 0.99-1.14). The OR for post-menopausal women with GSTM1 deficiency was determined to be 1.19 (95% CI, 1.05-1.34). In populations with a low frequency of GSTM1 deficiency, a greater increase was observed (OR, 1.20; 95% CI, 1.08-1.34). Furthermore, the highest associations were found in post-menopausal women with a low...
Journal of preventive medicine and public health = Yebang Ŭihakhoe chi, 2006
This study was to investigate if the dipstick proteinuria can predict cardiovascular mortality in... more This study was to investigate if the dipstick proteinuria can predict cardiovascular mortality in a population of Korean men. We measured urine protein and other cardiovascular risk factors in 100,059 Korean men, aged between 35-59 years in 1990 and 1992. Levels of proteinuria measured by dipstick method were trace or less, 1+, 2+, and 3+ or greater. The primary outcomes were deaths from all causes, cardiovascular disease, cancer, and others in a 12 year follow-up from 1993 to 2004. The multivariate-adjusted relative risks (95% CI) for cardiovascular death according to the level of proteinuria (1+, 2+, 3+ and more) in 1990 examination were 2.18 (1.36-3.48), 2.55 (1.37-4.78), and 4.57 (2.16-9.66) respectively. The corresponding relative risks according to the level of proteinuria in 1992 examination were 2.49 (1.71-3.64), 2.64 (1.53-4.58), and 2.78 (1.15-6.73). The relative risks for cardiovascular death of men with proteinuria (1+ or greater) once and twice among the examinations we...
To propose an efficient screening schedule for breast cancer among Korean women using the stochas... more To propose an efficient screening schedule for breast cancer among Korean women using the stochastic model in which the age-specific incidence rate was considered. Female breast cancer data in the Korea Central Cancer Registry 2002. The stochastic model was based on the threshold method, in which the schedule is determined by a pre-specified threshold value. The threshold value was defined as the probability of being in a preclinical state of breast cancer at age 40 years. The sensitivity of the mammography was specified as 0.7. Two models for mean sojourn time (MST) in the preclinical state were considered; MSTs for Model I were 2 (ages < 50 years), 3 (ages 50-59 years), and 4 years (ages > or = 60 years), and MSTs for Model II were 3, 4, and 5 years for the corresponding age groups. The threshold method for Model I generated 19 examinations within the screening ages of 40-69 years. Each screening time was determined at ages 40.0, 41.6, 43.2, 44.8, 46.0, 47.2, 48.4, 49.6, 50....
SummaryThe degree of thrombus resolution directly indicates the effectiveness of a thrombolytic d... more SummaryThe degree of thrombus resolution directly indicates the effectiveness of a thrombolytic drug. We investigated the degree of thrombus resolution and factors associated with thrombus resolution after intravenous (IV) recombinant tissue plasminogen activator (rt-PA) using thin-section noncontrast computed tomography (NCT). Thin-section NCTs were performed before and immediately after IV rt-PA infusion in acute stroke patients. The thrombus volume and Hounsfield unit were measured using three-dimensional imaging software. Immediate recanalisation was assessed immediately after IV rt-PA infusion using CT angiography. During a three-year study period, 130 patients were prospectively enrolled. On baseline thin-section NCT, no thrombi were found in 30 patients (23%). Among the 100 patients with confirmed thrombus, the median volume decreased by 20% on the follow-up NCT. The thrombus was completely resolved in 8%. Of note, an increase in thrombus volume was observed in 20 patients. I...
Frameshift mutation at coding mononucleotide repeat sequences are common in tumors with microsate... more Frameshift mutation at coding mononucleotide repeat sequences are common in tumors with microsatellite instability (MSI-H), but the incidences are different among the target genes. We analyzed the mutational profiles of 12 known target genes containing polydeoxyadenosine repeats in their coding sequences in 39 MSI-H colorectal carcinomas and 40 MSI-H gastric carcinomas by using polymerase chain reaction and sequencing, and compared the results with the clinicopathologic characteristics. Frameshift mutations of target genes in the MSI-H colorectal and gastric carcinomas are increased according to the length of the polydeoxyadenosine repeats in the target genes. The mean mutational rates of MSI-H colorectal carcinomas and MSI-H gastric carcinomas were 2.03 and 1.95 in the 4 genes containing (A)10 repeats, 1.23 and 0.73 in the 4 genes with (A)9 repeats and 0.61 and 0.48 in the 4 genes containing (A)8 repeats, respectively (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Among the evaluated clinicopathologic findings, intestinal type gastric carcinomas had more frameshift mutations than the diffuse type carcinomas (3.5 vs. 1.9, p=0.01). These findings suggest that mutational rates of the target genes in MSI-H tumors are diverse, and higher mutational rates are related to the length of mononucleotide repeat sequences of the target genes and histologic type of tumors.
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