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Different Risk Groups (different + risk_groups)
Selected AbstractsTransesophageal Echocardiography Risk Factors for Stroke in Nonvalvular Atrial FibrillationECHOCARDIOGRAPHY, Issue 4 2000F.R.C.P.C., SUSAN M. FAGAN M.D. Atrial fibrillation is a common arrhythmia, particularly in the older age groups. It confers an increased risk of thromboembolism to these patients, and multiple clinical risk factors have been identified to be useful in predicting the risks of thromboembolic events. Recent studies have evaluated the role of transesophageal echocardiography (TEE) in the evaluation of patients with atrial fibrillation. The purpose of this review is to evaluate the significance of transesophageal echocardiography findings in the prediction of thromboembolic events, particularly stroke, in patients with nonvalvular atrial fibrillation, with an emphasis on recently reported prospective studies. Aortic plaque and left atrial appendage abnormalities are identified as independent predictors of thromboembolic events. Although they are associated with clinical events, they also have independent incremental prognostic values. Other transesophageal echocardiographic findings, such as patent foramen ovale and atrial septal aneurysm, have not been found to be predictors of thromboembolic events in this patient group. Thus, TEE is a useful tool in stratifying patients with nonvalvular atrial fibrillation into different risk groups in terms of thromboembolic events, and it will likely play an important role in future studies to assess new treatment strategies in high-risk patients with atrial fibrillation. [source] Genetic characterization of hepatitis C virus strains in Estonia: Fluctuations in the predominating subtype with timeJOURNAL OF MEDICAL VIROLOGY, Issue 4 2007Tatjana Tallo Abstract During the last decade, there has been a dramatic increase in intravenous drug use in young adults in Estonia with an increased incidence of both hepatitis B and C as a consequence. Since genetic data are limited regarding hepatitis C virus (HCV) strains in Estonia, the aim of the study was to characterize HCV strains in different risk groups to determine their relatedness to strains from other geographical regions. Three hundred fifty-three anti-HCV positive sera collected during 1994,2004 from hospitalized patients, blood donors and health care workers were used as source of HCV RNA. Two hundred nine (59%) of the sera were positive for HCV RNA by PCR directed to the 5,-UTR region. For 174 strains the HCV subtype was determined by analyses of the NS5B and/or the 5,UTR-core regions. 1b (71%) was the most common subtype followed by 3a (24%), 2c (2%), 1a (1%), and 2a (1%). The 1b and 3a strains were similar to strains from other regions of the former USSR. Within genotype 1b there were several HCV lineages. However, for 3a there seemed to be two separate introductions into Estonia. There was a relative shift from subtype 1b to 3a in 1999,2000 with a further replacement of 3a with 1b in intravenous drug users in 2001 and onwards (P,<,0.05). However, both subtypes were found to co-circulate in the community independent of risk factors. One patient was infected with the 2k/1b recombinant presumed to originate from St. Petersburg being the first isolate of this recombinant recovered outside Russia. J. Med. Virol. 79:374,382, 2007. © 2007 Wiley-Liss, Inc. [source] Risk-Group-Specific Dose Finding Based on an Average Toxicity ScoreBIOMETRICS, Issue 2 2010B. Nebiyou Bekele Summary We propose a Bayesian dose-finding design that accounts for two important factors, the severity of toxicity and heterogeneity in patients' susceptibility to toxicity. We consider toxicity outcomes with various levels of severity and define appropriate scores for these severity levels. We then use a multinomial-likelihood function and a Dirichlet prior to model the probabilities of these toxicity scores at each dose, and characterize the overall toxicity using an average toxicity score (ATS) parameter. To address the issue of heterogeneity in patients' susceptibility to toxicity, we categorize patients into different risk groups based on their susceptibility. A Bayesian isotonic transformation is applied to induce an order-restricted posterior inference on the ATS. We demonstrate the performance of the proposed dose-finding design using simulations based on a clinical trial in multiple myeloma. [source] Construction of the Chinese University Prognostic Index for hepatocellular carcinoma and comparison with the TNM staging system, the Okuda staging system, and the Cancer of the Liver Italian Program staging systemCANCER, Issue 6 2002A study based on 926 patients Abstract BACKGROUND The current TNM staging system for patients with hepatocellular carcinoma (HCC) does not include liver function parameters and does not provide a precise prognosis for patients in different risk groups. The objectives of this study were to construct a new prognostic index for patients with hepatocellular carcinoma, the Chinese University Prognostic Index (CUPI), and to compare it with existing staging systems in terms of their ability to classify patients into different risk group. METHODS From 1996 to 1998, 926 ethnic Chinese patients who were diagnosed with HCC (mainly hepatitis B-associated) at a single institution were recruited prospectively into this study. A multivariate analysis on 19 patient characteristics was performed using a Cox regression model to identify independent prognostic factors. Weights were derived from the regression coefficients of various factors to construct the CUPI. Patients were classified according to different staging systems. Survival curves were plotted with the Kaplan,Meier method and were compared by using a log-rank test. RESULTS Both the TNM staging system and the Okuda staging system had prognostic significance, but the significance was lower for the Cancer of the Liver Italian Program (CLIP) prognostic score among the patients in the study population. The CUPI was constructed by adding the following factors into the TNM staging system: total bilirubin, ascites, alkaline phosphatase, , fetoprotein, and asymptomatic disease on presentation. The new CUPI characterized three risk groups with highly significant differences in survival during the whole period of follow-up (P < 0.00001) and was more discriminant than the other systems. CONCLUSIONS In the study population of patients with mainly hepatitis B-associated HCC, the CUPI was more discriminant than the TNM staging system, the Okuda staging systems, or the CLIP prognostic score in classifying patients into different risk groups and was better at predicting survival. The CUPI needs to be validated by different cohorts of patients before it can be recommended for general use. Cancer 2002;94:1760,9. © 2002 American Cancer Society. DOI 10.1002/cncr.10384 [source] | ||||||||||