Cheng-Wei Chang

Diabetic Patients with Severe Sepsis Admitted to Intensive Care Unit Do Not Fare Worse than Non-Diabetic Patients: A Nationwide Population-Based Cohort Study

Background We sought to examine whether type 2 diabetes increases the risk of acute organ dysfunction and of hospital mortality following severe sepsis that requires admission to an intensive care unit (ICU). Methods Nationwide population-based retrospective cohort study of 16,497 subjects with severe sepsis who had been admitted for the first time to an ICU during the period of 1998–2008. A diabetic cohort (n = 4573) and a non-diabetic cohort (n = 11924) were then created. Relative risk (RR) of organ dysfunctions, length of hospital stay (LOS), 90-days hospital mortality, ICU resource utilization and hazard ratio (HR) of mortality adjusted for age, gender, Charlson-Deyo comorbidity index score, surgical condition and number of acute organ dysfunction, were compared across patients with severe sepsis with or without diabetes. Results Diabetic patients with sepsis had a higher risk of developing acute kidney injury (RR, 1.54; 95% confidence interval (CI), 1.44–1.63) and were more likely to be undergoing hemodialysis (15.55% vs. 7.24%) in the ICU. However, the diabetic cohort had a lower risk of developing acute respiratory dysfunction (RR = 0.96, 0.94–0.97), hematological dysfunction (RR = 0.70, 0.56–0.89), and hepatic dysfunction (RR = 0.77, 0.63–0.93). In terms of adjusted HR for 90-days hospital mortality, the diabetic patients with severe sepsis did not fare significantly worse when afflicted with cardiovascular, respiratory, hepatic, renal and/or neurologic organ dysfunction and by numbers of organ dysfunction. There was no statistically significant difference in LOS between the two cohorts (median 17 vs. 16 days, interquartile range (IQR) 8–30 days, p = 0.11). Multiple logistic regression analysis to predict the occurrence of mortality shows that being diabetic was not a predictive factor with an odds ratio of 0.972, 95% CI 0.890–1.061, p = 0.5203. Interpretation This large nationwide population-based cohort study suggests that diabetic patients do not fare worse than non-diabetic patients when suffering from severe sepsis that requires ICU admission.

Acarbose Treatment and the Risk of Cardiovascular Disease in Type 2 Diabetic Patients: A Nationwide Seven-Year Follow-Up Study

Objective. To investigate the potential benefits of acarbose treatment on cardiovascular disease (CVD) in patients with type 2 diabetes by using nationwide insurance claim dataset. Research Design and Methods. Among 644,792 newly diagnosed type 2 diabetic patients without preexisting CVD in a nationwide cohort study, 109,139 (16.9%) who had received acarbose treatment were analyzed for CVD risk. Those with CVD followed by acarbose therapy were also subjected to analysis. Result. During 7 years of follow-up, 5,081 patients (4.7%) developed CVD. The crude hazard ratio (HR) and adjusted HR were 0.66 and 0.99, respectively. The adjusted HR of CVD was 1.19, 0.70, and 0.38 when the duration of acarbose use was <12 months, 12–24 months, and >24 months, respectively. Adjusted HR was 1.14, 0.64, and 0.41 with acarbose cumulative doses <54,750 mg, 54,751 to 109,500 mg, and >109,500 mg, respectively. Conclusion. In patients with type 2 diabetes without preexisting CVD, treatment with acarbose showed a transient increase in incidence of CVD in the initial 12 months followed by significant reductions of CVD in prolonged acarbose users. After the first CVD events, continuous use of acarbose revealed neutral effect within the first 12 months. The underlying mechanisms require further investigations.

Development Pattern Recognition Model for the Classification of Circuit Probe Wafer Maps on Semiconductors

Spatial defect patterns generated during integrated circuit (IC) manufacturing contain valuable information on the fabrication process and can help engineers identify the root causes of any defect. Classification of these defect patterns is crucial to improving reliability and yield during IC manufacturing. Accurate classification requires good feature selection in order to assist in identifying the defect cluster types. In this paper, we demonstrate that the linear Hough transformation, the circular Hough transformation incorporating the cover ratio approach, and the zone ratio approach, when used as feature-extraction techniques, are able to distinguish lines, various solid circle-like cluster patterns such as blobs and bulls-eyes, and various hollow circle-like cluster patterns such as rings and edges. On the basis of these features, in this paper we provide a comprehensive evaluation of several data-mining classification approaches in terms of performance and accuracy. The results obtained using both artificial and real manufacturing data demonstrate the potential of this approach for analyzing general defect patterns that are generated during the IC fabrication process.

Risk of Tuberculosis in Children with Juvenile Idiopathic Arthritis: A Nationwide Population-Based Study in Taiwan.

Objective We aimed to determine the risk of tuberculosis in children with juvenile idiopathic arthritis (JIA) in Taiwan. Methods We used the Taiwan National Health Insurance Research Database (NHIRD) to conduct a nested case-control study. We identified a JIA cohort and matched each JIA child with non-JIA children for comparison. Methotrexate (MTX), tumor necrosis factor (TNF) inhibitor administration, and new tuberculosis cases were determined during our study period. To compare tuberculosis (TB) risk among our study groups, Cox proportional regression models were used to determine adjusted hazard ratios (aHRs). Results We identified 1495 children with JIA and 11592 non-JIA children. Majority (68.7%) children with JIA had not received MTX or TNF inhibitors; 23.9% used MTX without TNF inhibitors, and 7.4% received TNF inhibitors, irrespective of MTX administration. In total, 43 children developed tuberculosis. The overall tuberculosis infection rate for children with JIA was two times higher than that for non-JIA children. Compared with non-JIA children, children with JIA who used MTX without TNF inhibitors revealed a significantly increased of tuberculosis infection rate (aHR = 4.67; 95% CI: 1.65–13.17; P = 0.004). Children with JIA who either received TNF inhibitors or never used MTX and TNF inhibitors revealed a tuberculosis infection rate comparable to that of non-JIA children. Conclusions Analysis of nationwide data of Taiwan suggested that children with JIA were at higher risk of tuberculosis compared with those without JIA.

Association between History of Dental Amalgam Fillings and Risk of Parkinson's Disease: A Population-Based Retrospective Cohort Study in Taiwan.

The impact of dental amalgam on the development of Parkinson’s disease (PD) is still uncertain, although a positive association between dental amalgam and PD has been found in a few case-control studies. The patients with amalgam fillings restored between 2000 and 2008 were identified by using the National Health Insurance Research Database (NHIRD) in Taiwan. The same number of patients who had no new amalgam filling restored was matched by sex, age, and treatment date. Both cohorts were followed up from the treatment date until the date of diagnosis of PD, death, or the end of the year 2008. The individuals who received amalgam fillings had a significantly higher risk of PD afterward (adjusted hazard ratio [HR]=1.583, 95% confidence interval [CI]=1.122–2.234, p=0.0089) than those who did not. In the individuals who received amalgam fillings, being diagnosed with diabetes or hyperlipidemia demonstrated a significantly lower HR of PD occurrence than in the patients without diabetes or hyperlipidemia (HR=0.449, 95% CI=0.254–0.794, p=0.0059; HR=0.445, 95% CI=0.260–0.763, p=0.0032) after adjusting for comorbidities and Charlson-Deyo Comorbidity Index (CCI) scores. Meanwhile, hypertension increased the hazard risk of PD (HR=1.645, 95% CI=1.098–2.464, p=0.0159). The patients exposed to dental amalgam fillings were 1.583 times more likely to have PD afterward compared to their non-exposed counterparts after adjusting for comorbidities and CCI scores.

Evaluation of the Appropriate Age Range of Colorectal Cancer Screening Based on the Changing Epidemiology in the Past 20 Years in Taiwan

Introduction. According to the recommendation of the United States Preventative Services Task Force, most countries provide average-risk screening for colorectal cancers (CRCs) between the ages of 50 and 75 years. However, the age range of screening should be modified because of an increasing life span. Methods. Totally 124,314 CRC cases were registered in Taiwan Cancer Registry from 1988 to 2007. The 20-year study period was divided into four 5-year increments. We divided the patients into four age groups (under age 50, age 50–74, age 74–84, and over age 85) in each increment to determine whether there were changes in the age distribution. Results. In the subgroup of patients under age 50, the number of CRC cases increased, but they accounted for a decreasing proportion of the total CRCs. In the 50–74 age group, the proportion of CRC cases also dropped. In contrast, the proportion increased in the 75–84 age group. Therefore, 43.63% of CRC patients would not be delegated to screen in the period of 2003–2007 if the CRC screening were restricted in the 50–74 age group. Conclusions. CRC screening for healthy individuals aged over 75 years is necessary.

Mean Daily Dosage of Aspirin and the Risk of Incident Alzheimer’s Dementia in Patients with Type 2 Diabetes Mellitus: A Nationwide Retrospective Cohort Study in Taiwan

Background. Type 2 diabetes mellitus patients are known to have higher risk of developing dementia while aspirin use has been shown to prevent incident dementia. This study was conducted to evaluate the potential benefits of aspirin use on dementia in patients with type 2 diabetes mellitus and identify the appropriate dosage of aspirin that provides the most benefit. Method. A Taiwan nationwide, population-based retrospective 8-year study was employed to analyze the association between the use of aspirin and incidence of dementia including Alzheimers disease and non-Alzheimers dementia using multivariate Cox-proportional hazards regression model and adjusting for several potential confounders. Results. Regular aspirin use in mean daily dosage of within 40 mg was associated with a decreased risk of developing incident Alzheimers dementia in patients with type 2 diabetes mellitus (adjusted HR of 0.51 with 95% CI of 0.27–0.97, p value 0.041). Conclusion. A mean daily dosage of aspirin use within 40 mg might decrease the risk of developing Alzheimers disease in patients with type 2 diabetes mellitus.

Increased risk of dental trauma in patients with allergic rhinitis: A nationwide population-based cohort study

Allergic rhinitis (AR) is associated with various developmental issues that affecting dentition. We aimed to determine whether AR is associated with an increased risk of traumatic dental injuries (TDIs) in Taiwanese individuals. We used the Taiwan National Health Insurance Research Database (NHIRD) to conduct a nested case-control study. We compared an AR cohort with a matched cohort of patients without AR. New TDI cases were determined during our study period. To compare TDI risk between our study cohorts, we used Cox proportional regression analysis, and hazard ratios (HR) with 95% confidence intervals (CI) were calculated to quantify the association between AR exposure and TDI risk. In total, 76749 patients with AR (31715 male; 45034 female) were identified. In the AR and the non-AR cohorts, 312 patients in total had TDI. Patients with AR had a significantly higher risk of TDI than those without AR (aHR = 1.92; 95% CI = 1.459–2.525; P < 0.001). The risk of TDI was markedly higher in the AR cohort, except in the 3–12-year-old group, and with a CCI ≥ 1. AR patients had a future risk of TDI, indicating a potentially linked disease pathophysiology. The association between AR and TDI is greater among general patients. Clinicians and caregivers should be aware of potential TDI co-morbidity in patients with AR.

A Prediction of mRNA Polyadenylation Sites in Human Genes

mRNA polyadenylation is an essential mechanism in human genes and is direct linked to the termination of transcription. Alternative polyadenylation changes the length of the mature mRNA’s 3’UTR. Since 3’UTRs have been shown to contain regulatory elements that control mRNA functioning, alternative polyadenylation plays an important role in controlling the expression of human genes. Prediction of polyadenylation sites can help with the identification of genes and aid our understanding of the mechanisms of alternative polyadenylation. In this study, we constructed a system for mRNA polyadenylation site prediction in human genes using SVM and based on an analysis of the sequence alignment between pair-end diTags (PET) and genome sequences. The PET sequences were mapped to the reference genome more accurate compared to earlier methods. We also analyzed single-site type and multiple-site type sequences PET sequence datasets and found that the frequencies of each nucleotide were different when the single-site type and multiple-site type PET sequences were compared.

A System to Discover Correlations within a Biological Pathway between the Expression Levels of Genes

Current pathway presentation method to the biologist is static graph. The analysis of differentially expressed genes using microarray gene expression data can help to find factors that affect diseases. However, the differentially expressed genes that are identified may be too large in number and its difficult for biologist to pinpoint the correlations between genes and crucial points on pathway interactively. In this study, we propose a method that attempts to avoid this problem and allows the discovery of greater biological meaning than the traditional method. We select a gene pair set of interacting genes in a biological pathway and investigate the correlation in expression between the gene pairs under different condition (such as relapsed and non-relapsed breast cancer) using microarray gene expression data. We tested the approach using breast cancer relapsed and non-relapsed datasets in order to demonstrate that our method is both useful and reliable; very stable results were obtained when the same microarray platform was used. We finally use an interface to display correlations within a biological pathway.