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Cox Analysis (cox + analysis)
Kinds of Cox Analysis Selected AbstractsLong QT Syndrome in African-AmericansANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2010Thomas Fugate II B.S. Background: We evaluated the risk factors and clinical course of Long QT syndrome (LQTS) in African-American patients. Methods: The study involved 41 African-Americans and 3456 Caucasians with a QTc , 450 ms from the U.S. portion of the International LQTS Registry. Data included information about the medical history and clinical course of the LQTS patients with end points relating to the occurrence of syncope, aborted cardiac arrest, or LQTS-related sudden cardiac death from birth through age 40 years. The statistical analyses involved Kaplan-Meier time to event graphs and Cox regression models for multivariable risk factor evaluation. Results: The QTc was 29 ms longer in African-Americans than Caucasians. Multivarite Cox analyses with adjustment for decade of birth revealed that the cardiac event rate was similar in African-Americans and Caucasians with LQTS and that beta-blockers were equally effective in reducing cardiac events in the two racial groups. Conclusions: The clinical course of LQTS in African-Americans is similar to that of Caucasians with comparable risk factors and benefit from beta-blocker therapy in the two racial groups. Ann Noninvasive Electrocardiol 2010;15(1):73,76 [source] The Effect of Anemia on Mortality in Indigent Patients With Mild-to-Moderate Chronic Heart FailureCONGESTIVE HEART FAILURE, Issue 2 2006Kathy Hebert MD Anemia has been described as an independent predictor of death in patients with chronic heart failure. Little is known, however, about the significance of anemia in heart failure patients with severely depressed socioeconomic backgrounds who receive comprehensive care in a heart failure management program. The impact of anemia on mortality was investigated in 410 indigent chronic heart failure patients, the majority of whom were in New York Heart Association functional class I,III and were treated with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and , blockers at maximally tolerated doses. Anemia was present in 28% of patients. In an adjusted Cox analysis, anemia was strongly associated with mortality, but only in men: hazard ratio, 2.54; 95% confidence interval, 1.31,4.93; p=0.006. The investigators conclude that anemia in this population is common and that, for men, the relative risk increase associated with anemia is high. [source] Elective neck dissection in early-stage oral squamous cell carcinoma,does it influence recurrence and survival?HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 1 2007Ana Capote MD Abstract Background. This study investigates the influence on survival and regional control rates of neck dissection therapy at the time of surgery of the primary tumor in early stages of squamous cell carcinoma (SCC) of the oral cavity. Methods. A series of 154 patients with pT1N0M0 and pT2N0M0 intraoral carcinomas was analyzed retrospectively. Neck dissection was associated with tumor ablation in 87 patients (56.5%), although 67 patients (43.5%) were treated with local resection exclusively. Survival and relapse rates were studied with the Kaplan,Meier curves and the log-rank test for univariate analysis and Cox proportional model for multivariate analysis (p < .05). Results. Regional recurrences occurred in 25 cases (16.2%), 7 cases (8%) with primary neck dissection and 18 cases (26.8%) with local excision alone. Neck dissection therapy was a significant prognostic factor for recurrences and survival (p < .05). The 5-year regional control rate was of 92.5% for patients with elective lymph node ablation versus 71.2% for patients without primary neck dissection. Neck dissection was also significant for recurrences in stage I and for survival and recurrences in stage II. Neck dissection therapy also showed independent prognostic value in the Cox analysis. Conclusions. In patients with intraoral carcinomas, elective neck treatment should be considered even in cases with a small primary tumor and negative clinical examination because of the high incidence of occult nodal metastases and the tendency to regional recurrences. © 2006 Wiley Periodicals, Inc. Head Neck 2007 [source] Prognostic significance of the therapeutic targets histone deacetylase 1, 2, 6 and acetylated histone H4 in cutaneous T-cell lymphomaHISTOPATHOLOGY, Issue 3 2008L Marquard Aims:, Aberrant histone acetylation has been associated with malignancy and histone deacetylase (HDAC) inhibitors are currently being investigated in numerous clinical trials. So far, the malignancy most sensitive to HDAC inhibitors has been cutaneous T-cell lymphoma (CTCL). The reason for this sensitivity is unclear and studies on HDAC expression and histone acetylation in CTCL are lacking. The aim of this study was to address this issue. Methods and results:, The immunohistochemical expression of HDAC1, HDAC2, HDAC6, and acetylated H4 was examined in 73 CTCLs and the results related to histological subtypes and overall survival. HDAC1 was most abundantly expressed (P < 0.0001), followed by HDAC2; HDAC6 and H4 acetylation were equally expressed. HDAC2 (P = 0.001) and H4 acetylation (P = 0.03) were significantly more common in aggressive than indolent CTCL subtypes. In contrast, no differences were observed for HDAC1 and HDAC6. In a Cox analysis, elevated HDAC6 was the only parameter showing significant influence on survival (P = 0.04). Conclusions:, High expression of HDAC2 and acetylated H4 is more common in aggressive than indolent CTCL. HDAC6 expression is associated with a favorable outcome independent of the subtype. [source] High serum levels of YKL-40 in patients with squamous cell carcinoma of the head and neck are associated with short survivalINTERNATIONAL JOURNAL OF CANCER, Issue 4 2008Anne Roslind Abstract YKL-40 is a glycoprotein secreted by macrophages, neutrophils and malignant tumor cells. Elevated serum levels of YKL-40 are associated with poor prognosis in several malignancies. In this study, we examined the prognostic value of serum YKL-40 before treatment and during follow-up in patients with squamous cell carcinoma of the head and neck (HNSCC). YKL-40 was determined by ELISA retrospectively in serum from 173 patients with primary HNSCC before treatment and up to 2 years after treatment. Median follow-up time was 7.9 years. YKL-40 protein expression in tumor biopsies was assessed by immunohistochemistry in 50 patients. Pretreatment serum YKL-40 was elevated in 53%. Patients with high serum YKL-40 had shorter survival than patients with normal serum YKL-40 (33 vs. 84 months; p = 0.008). Multivariate Cox analysis including pretreatment serum YKL-40, age, sex, primary tumor site, TNM classification and treatment demonstrated that TNM classification (HR = 2.61, p = 0.02) and serum YKL-40 (log-transformed continuous variable: HR = 1.55, p < 0.0001) were independent prognostic variables of overall survival (OS). Multivariate Cox analysis demonstrated that TNM classification (HR = 5.77, p = 0.001) and serum YKL-40 (dichotomous variable: HR = 2.75, p = 0.01) were independent predictors of recurrence-free survival. During follow-up after radiotherapy, a high serum YKL-40 (log-transformed continuous variable) in patients with TNM Stage III and IV disease predicted poorer OS within 6 months (HR = 1.95, p < 0.0001). Immunohistochemical analysis showed YKL-40 expression in the malignant tumor cells. In conclusion, serum YKL-40 was demonstrated to be an independent prognostic biomarker of recurrence-free and overall survival in patients with HNSCC. © 2007 Wiley-Liss, Inc. [source] Impact of primary tumour stage on survival in dogs with solitary lung tumoursJOURNAL OF SMALL ANIMAL PRACTICE, Issue 2 2008G. A. Polton Objectives: The objective of this study was to determine simple prognostic criteria for differentiation of canine solitary lung tumour cases into those that will and will not benefit from thoracic surgery. Methods: This was a retrospective study using the records of cases presented to Davies Veterinary Specialists, Hitchin, UK, from December 1998 to December 2005. Survival analyses were performed using the Kaplan-Meier and logrank methods. Potentially significant variables were evaluated by multivariate Cox analysis. Results: Forty-two patients met the inclusion criteria. Primary tumour stage T1, absence of neoplastic lymph nodes and metastases, and papillary tumour type were statistically significant favourable prognostic indicators on univariate analysis. Multivariate analysis attributed significance to primary tumour stage T1 and papillary type only. Median survival times were 555 days for T1N0M0 tumours of papillary type and 72 days for the remainder. Clinical Significance: Survival time following surgery in dogs with primary lung tumours was poor except in clinical stage T1N0M0 cases. These data support use of clinical techniques to dichotomise cases as T1N0M0 or other, improving decision making in thoracic surgery. These data validate initiation of prospective studies examining the role of chemotherapy in the management of advanced cases. [source] Natural course of treated and untreated chronic HCV infection: results of the nationwide Hepnet.Greece cohort studyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2009E. K. MANESIS Summary Background, Interferon (IFN-,)-based regimens have been used with varying success in the treatment of chronic hepatitis C (CHC) for over two decades. The effect of such treatments on the natural course of CHC has been evaluated in small clinical trials with conflicting results. Aim, To investigate the natural course of IFN,-based -treated and untreated patients with CHC by analysing data from the HEPNET.GREECE study. Methods, We retrospectively analysed 1738 patients from 25 Greek Centres (median age 40.1; males 57.6%; cirrhosis 9.2%), 734 untreated and 993 treated with IFN,-based regimens [44.7% sustained viral response (SVR)], followed-up for median 25.2 and 46.8 months, respectively. Results During follow-up, 48 patients developed liver decompensation and 24 HCC. Older age was significantly related to disease progression (HR = 2.6 per 10 years of increasing age). Stratified by baseline cirrhosis, Cox analysis showed that patients with SVR, but not without SVR, had significantly lower hazard for events compared with nontreated patients (HR = 0.16; P < 0.001), whereas the detrimental effect of older age remained highly significant. Separate group analysis demonstrated that in cirrhosis, the beneficial effect of treatment was evident even without SVR. Treatment effect interacted significantly with age, indicating that older patients, mainly noncirrhotic, gained the most benefit. Conclusions IFN,-based treatment does alter the natural course of CHC. A protective effect is mostly present in patients with SVR, but older patients, at higher risk of events, gain the greatest benefit. In established cirrhosis, treatment carries a protective effect even among those without SVR. [source] Risk factors for recurrence of autoimmune hepatitis after liver transplantation,,LIVER TRANSPLANTATION, Issue 10 2009Aldo J. Montano-Loza Autoimmune hepatitis has been reported to recur after liver transplantation. The aim of our study was to evaluate the risk factors associated with recurrence of autoimmune hepatitis. Forty-six patients that underwent liver transplantation because of end-stage liver disease secondary to autoimmune hepatitis were studied. Recurrence of autoimmune hepatitis was diagnosed in 11 of the 46 (24%) patients, and the overall 5-year probability of recurrence was 18%. By univariate Cox analysis, the features before liver transplantation associated with a higher risk of recurrence were concomitant autoimmune disease [hazard ratio (HR), 3.74; 95% confidence interval (CI), 1.05,13.36; P = 0.04], high aspartate aminotransferase (HR, 1.09; 95% CI, 1.03,1.14; P = 0.002), high alanine aminotransferase (HR, 1.09; 95% CI, 1.03,1.20; P = 0.003), and high immunoglobulin G (IgG; HR, 1.25; 95% CI, 1.11,1.41; P = 0.0003). Moreover, patients with recurrence had a higher frequency of moderate to severe inflammatory activity (HR, 5.3; 95% CI, 1.55,18.79; P = 0.008) and plasma cell infiltration in the liver explant (HR, 5.8; 95% CI, 1.52,22.43; P = 0.01). In the multivariate Cox analysis, only the presence of moderate to severe inflammation (HR, 6.9; 95% CI, 1.76,26.96; P = 0.006) and high IgG levels before liver transplantation (HR, 7.5; 95% CI, 1.45,38.45; P = 0.02) were independently associated with the risk of autoimmune hepatitis recurrence. In conclusion, patients with concomitant autoimmune disease, high aspartate aminotransferase, alanine aminotransferase, and IgG before the transplant, or moderate to severe inflammatory activity or plasma cell infiltration in the liver explant have a higher risk of recurrent disease. These findings suggest that recurrence of autoimmune hepatitis may reflect incomplete suppression of disease activity prior to liver transplantation. Liver Transpl 15:1254,1261, 2009. © 2009 AASLD. [source] Postmarketing drug dosage changes of 499 FDA-approved new molecular entities, 1980,1999,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 6 2002James Cross MS Abstract Purpose Risks and benefits of marketed drugs can be improved by changing their labels to optimize dosage regimens for indicated populations. Such postmarketing label changes may reflect the quality of pre-marketing development, regulatory review, and postmarketing surveillance. We documented dosage changes of FDA-approved new molecular entities (NMEs), and investigated trends over time and across therapeutic groups, on the premise that improved drug development methods have yielded fewer postmarketing label changes over time. Methods We compiled a list of NMEs approved by FDA from 1 January 1980 to 31 December 1999 using FDA's website, Freedom of Information Act request, and PhRMA (Pharmaceutical Research and Manufacturers of America) database. Original labeled dosages and indicated patient populations were tracked in labels in the Physician's Desk Reference®. Time and covariate-adjusted risks for dosage changes by 5-year epoch and therapeutic groups were estimated by survival analysis. Results Of 499 NMEs, 354 (71%) were evaluable. Dosage changes in indicated populations occurred in 73 NMEs (21%). A total of 58 (79%) were safety-motivated, net dosage decreases. Percentage of NMEs with changes by therapeutic group ranged from 27.3% for neuropharmacologic drugs to 13.6% for miscellaneous drugs. Median time to change following approval fell from 6.5 years (1980,1984) to 2.0 years (1995,1999). Contrary to our premise, 1995,1999 NMEs were 3.15 times more likely to change in comparison to 1980,1984 NMEs (p,=,0.008, Cox analysis). Conclusions Dosages of one in five NMEs changed, four in five changes were safety reductions. Increasing frequency of changes, independent of therapeutic group, may reflect intensified postmarketing surveillance and underscores the need to improve pre-marketing optimization of dosage and indicated population. Copyright © 2002 John Wiley & Sons, Ltd. [source] Cyclosporine A Protects Against Primary Biliary Cirrhosis Recurrence After Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2010A. J. Montano-Loza Primary biliary cirrhosis (PBC) reoccurs in a proportion of patients following liver transplantation (LT). The aims of our study were to evaluate the risk factors associated with PBC recurrence and determine whether recurrent disease constitutes a negative predictor for survival. One hundred and eight patients receiving LT for end-stage PBC were studied. Recurrent disease was diagnosed in 28 patients (26%). Probability of recurrent PBC at 5 years was 13% and 29% at 10 years with an overall incidence of 3.97 cases per 100 patient years. By univariate Cox analysis use of tacrolimus (HR 6.28, 95% CI, 2.44,16.11, p < 0.001) and mycophenolate mofetil (HR 5.21, 95% CI, 1.89,14.33, p = 0.001) were associated with higher risk of recurrence; whereas use of cyclosporine A (CsA) and azathioprine were associated with reduced risk of recurrence (HR 0.13, 95% CI 0.05,0.35, p < 0.001 and HR 0.27, 95% CI 0.11,0.64, p = 0.003, respectively). In the multivariate Cox analysis, only CsA was independently associated with protection against recurrence (HR 0.17, 95% CI 0.06,0.71, p = 0.02). Five-year probability of survival was 83% and 96%, in patients without and with recurrence (log-rank test, p = 0.3). Although PBC transplant recipients receiving CsA have a lower risk of disease recurrence, the development of recurrent PBC did not impact on long-term patient survival. [source] Similar Outcomes with Different Rates of Delayed Graft Function May Reflect Center Practice, Not Center PerformanceAMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2009S. K. Akkina To better understand the implications for considering delayed graft function (DGF) as a performance measure, we compared outcomes associated with a 2- to 3-fold difference in the incidence of DGF at two transplant centers. We analyzed 5072 kidney transplantations between 1984 and 2006 at the University of Minnesota Medical Center (UMMC) and Hennepin County Medical Center (HCMC). In logistic regression the adjusted odds ratio for DGF at HCMC versus UMMC was 3.11 (95% Confidence Interval [CI]= 2.49,3.89) for deceased donors and 2.24 (CI = 1.45,3.47) for living donors. In Cox analysis of 4957 transplantations, slow graft function (SGF; creatinine ,3.0 mg/dL [230 ,mol/L] on day 5 without dialysis) was associated with graft failure at UMMC (Relative Risk [RR]= 1.43, CI = 1.25,1.64), but not HCMC (RR = 0.99, CI = 0.77,1.28). RR's of DGF were similar at both centers. Thus, the lower incidence of DGF at UMMC likely resulted in a higher incidence and higher risk of SGF compared to HCMC. Indeed, graft survival for recipients with DGF at HCMC was similar (p = 0.3741) to that of recipients with SGF at UMMC. We conclude that dialysis per se is likely not a cause of worse graft outcomes. A better definition is needed to measure early graft dysfunction and its effects across transplant programs. [source] Increased Primary Non-Function in Transplanted Deceased-Donor Kidneys Flushed with Histidine-Tryptophan-Ketoglutarate SolutionAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2009R. B. Stevens Histidine-Tryptophan-Ketoglutarate (HTK) solution is increasingly used to flush and preserve organ donor kidneys, with efficacy claimed equivalent to University of Wisconsin (UW) solution. We observed and reported increased graft pancreatitis in pancreata flushed with HTK solution, which prompted this review of transplanting HTK-flushed kidneys. We analyzed outcomes of deceased-donor kidneys flushed with HTK and UW solutions with a minimum of 12 months follow-up, excluding pediatric and multi-organ recipients. We evaluated patient and graft survival and rejection rates, variables that might constitute hazards to graft survival and renal function. Two-year patient survival, rejection, renal function and graft survival were not different, but early graft loss (<6 months) was worse in HTK-flushed kidneys (p < 0.03). A Cox analysis of donor grade, cold ischemic time, panel reactive antibodies (PRA), donor race, first vs. repeat transplant, rejection and flush solution showed that only HTK use predicted early graft loss (p < 0.04; relative risk = 3.24), almost exclusively attributable to primary non-function (HTK, n = 5 (6.30%); UW, n = 1 (0.65%); p = 0.02). Delayed graft function and early graft loss with HTK occurred only in lesser grade kidneys, suggesting it should be used with caution in marginal donors. [source] Serum Autoantibodies Against Cytochrome P450 2E1 (CYP2E1) Predict Severity of Necroinflammation of Recurrent Hepatitis CAMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2009C. Rigamonti We previously reported that autoantibodies against cytochrome P4502E1 (CYP2E1) are frequent in patients with chronic hepatitis C. As autoimmune reactions are increasingly detected after orthotopic liver transplantation (OLT), this study investigates prevalence and significance of anti-CYP2E1 autoantibodies in 46 patients with post-OLT recurrent hepatitis C. IgG against recombinant human CYP2E1 above the control threshold was detected in 19 out 46 (41%) sera collected immediately before OLT and in 15 out 46 (33%) sera collected at the time of the 12 months follow-up liver biopsy. Although anti-CYP2E1 reactivity was not modified by OLT, the patients with persistently elevated anti-CYP2E1 IgG (n = 12; 26%) showed significantly higher prevalence of recurrent hepatitis with severe necroinflammation and fibrosis than those persistently negative or positive only either before or after OLT. Moreover, the probability of developing severe necroinflammation was significantly higher in persistently anti-CYP2E1-positive subjects. Multivariate regression and Cox analysis confirmed that the persistence of anti-CYP2E1 IgG, together with a history of acute cellular rejection and donor age >50 years, was an independent risk factor for developing recurrent hepatitis C with severe necroinflammation. We propose that autoimmune reactions involving CYP2E1 might contribute to hepatic damage in a subgroup of transplanted patients with recurrent hepatitis C. [source] Effectiveness of Prophylactic Anti-HBV Therapy in Allogeneic Hematopoietic Stem Cell Transplantation with HBsAg Positive DonorsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2005Chee-kin Hui Use of hepatitis B surface antigen (HBsAg) positive donors for allogeneic hematopoietic stem cell transplantation (HSCT) causes serious hepatitis B virus (HBV)-related liver morbidity and mortality in the recipient. We compared the effectiveness of anti-HBV therapy in 29 recipients who underwent HSCT using HBsAg positive marrow (group I) against a historical control group of 25 patients who received HBsAg positive marrow without pre-HSCT prophylaxis (group II). Anti-HBV therapy consisted of lamivudine for HBsAg-positive donors and all recipients (n = 29) as well as HBV vaccination to all HBsAg-negative recipients (n = 10) before HSCT. After transplantation, HBV-related hepatitis was significantly higher in group II than group I recipients [12 of 25 recipients (48%) vs. 2 of 29 recipients (6.9%), p = 0.002] and in recipients whose donors had detectable serum HBV DNA by Digene Hybrid Capture II assay [8 of 14 recipients (57.1%) vs. 6 of 40 recipients (15.0%), p = 0.02]. Six recipients in group II and none in group I died of HBV-related hepatic failure (24.0% vs. 0%, p = 0.01). By multivariate Cox analysis, anti-HBV therapy effectively reduces post-HSCT HBV-related hepatitis (p = 0.01, adjusted hazards ratio 7.27, 95%CI 1.62,32.58). Our data support the use of prophylactic therapy in preventing HBV-related hepatitis after allogeneic HSCT from HBsAg-positive donor. [source] Soluble urokinase-type plasminogen activator receptor (suPAR) as an independent factor predicting worse prognosis and extra-bone marrow involvement in multiple myeloma patientsBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2003Gian Matteo Rigolin Summary. The urokinase-type plasminogen activator (uPA) system, which consists of a proteinase (uPA), a receptor (uPAR or CD87) and inhibitors, is involved in proteolysis, cell migration, tissue remodelling, angiogenesis and cell adhesion. Recent findings suggest that malignant plasma cells express uPA and uPAR. The expression of these factors could represent a process by which myeloma plasma cells interact with the bone marrow (BM) environment and influence important biological events such as bone matrix degradation, plasma cell invasion and homing and, possibly, clinical evolution. We evaluated uPAR (CD87) and its soluble form (suPAR) in 49 multiple myeloma (MM) patients and correlated their expression and levels with clinico-biological characteristics of the disease. Flow cytometric analysis demonstrated that CD87 was expressed in all MM patients. High CD87 expression was associated with higher intensity of expression of CD56 (P = 0·038), CD38 (P = 0·058) and CD138 (P = 0·054) and CD45bright positivity (P = 0·014). suPAR levels correlated positively with soluble serum CD138 (P = 0·001), creatinine (P = 0·001), beta2 -microglobulin (P < 0·001), disease stage (P = 0·017) and extra-BM involvement (P = 0·002). In the 46 evaluable patients, multivariate analysis showed that high levels of suPAR (P = 0·0214) and disease stage (P = 0·0064) were predictive of extra-BM involvement. In multivariate Cox analysis, 13q deletion (P = 0·0278), high soluble serum CD138 (P = 0·0201) and high suPAR (P = 0·0229) were the only parameters that independently affected survival. We conclude that CD87 is expressed on myeloma plasma cells and that suPAR, which predicts extra-BM involvement and poor prognosis, possibly represents a molecule with a relevant role in the biology of MM. [source] Impact of bivalirudin on in-hospital bleeding and six-month outcomes in octogenarians undergoing percutaneous coronary intervention,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2009Gilles Lemesle MD Abstract Objectives: This study aimed to analyze the impact of replacing heparin with bivalirudin in octogenarians undergoing percutaneous coronary intervention (PCI) on postprocedure hemorrhage and 6-month mortality. Background: Randomized trials comparing the antithrombin agent bivalirudin with heparin as the intraprocedural anticoagulant identify a reduction in periprocedural bleeding after PCI. Further, the occurrence of such bleeding seems to predict an increased risk of death or myocardial infarction both in-hospital and at long-term follow-up. Importantly, elderly people who are at the greatest risk of post-PCI bleeding complications are underrepresented in these randomized trials. Methods: From 2000 to 2007, 2,766 consecutive patients from our center who were ,80 years of age underwent PCI with stent implantation and were included in this analysis. Bivalirudin was used in 1,207 (43.6%) patients and heparin in 1,559 (56.4%). We compared the rates of post-PCI bleeding complications and 6-month mortality. Results: The overall in-hospital bleeding and 6-month mortality rates were 4.6% and 11.8%, respectively. By multivariate logistic regression and after adjustment by propensity score analysis, bivalirudin was associated with a significant decrease in in-hospital bleedings (HR = 0.41, 95% CI = 0.23,0.73, P = 0.003). By multivariate Cox analysis, bivalirudin was also associated with a significant decrease (HR = 0.6, 95% CI = 0.4,0.9, P = 0.01) and in-hospital bleedings with a significant increase in the 6-month mortality (HR = 2.5, 95% CI = 1.6,3.9, P < 0.001). Conclusion: This study suggests an important subset for use of bivalirudin in lieu of heparin that will benefit the very elderly. © 2009 Wiley-Liss, Inc. [source] Neural networks compared with Cox regressionACTA OPHTHALMOLOGICA, Issue 2008B DAMATO Purpose Survival prediction is useful in patient care and research. Most studies rely on Cox analysis and Kaplan-Meier curves whereas we have preferred neural networks. The aim of this presentation is to compare these methods and to discuss the advantages and limitations of each. Methods This presentation will be based on our experience with uveal melanoma. A neural network was trained with data from 1780 patients and evaluated with data from another 874 patients. Clinical, histopathological and cytogenetic data were included in the model. All cause mortality was reported, both for patients and for the matched general population. Results Cox analysis assumes linear correlations between variables and proportional hazards throughout the follow-up period. Kaplan-Meier analysis requires large patient categories, so that the precision of any prognostication is reduced. Neural networks overcome these limitations. Our model does censor non-metastatic deaths so that melanoma-related mortality is not exaggerated in groups of patients with significant competing risks. Conclusion Neural networks allow large numbers of variables to be included in predictive models with relatively small numbers of patients, thereby improving prognostication. Nevertheless, care must be taken when interpreting survival results to avoid serious misconceptions about the natural history of a disease and the impact of treatment. [source] The hemodynamic response to medical treatment of portal hypertension as a predictor of clinical effectiveness in the primary prophylaxis of variceal bleeding in cirrhosisHEPATOLOGY, Issue 5 2000Carlo Merkel In the prevention of variceal rebleeding, it is already established that hemodynamic response to drug treatment (decrease in hepatic venous pressure gradient [HVPG] to 12 mm Hg or by >20%) is predictive of clinical effectiveness. In primary prophylaxis very few clinical data are available. We assessed the role of the hemodynamic response to beta-blockers or beta-blockers plus nitrates in predicting clinical efficacy of prophylaxis. A total of 49 cirrhotic patients with varices at risk of bleeding, without prior variceal bleeding, were investigated by hepatic vein catheterization before and after 1 to 3 months of chronic treatment with nadolol or nadolol plus isosorbide mononitrate, and were followed during treatment for up to 5 years. A total of 30 patients (61%) were good hemodynamic responders, and among them in 12 (24%) HVPG was ,12 mm Hg during treatment. During treatment 9 patients had variceal bleeding: 7 were poor responders and 2 were good responders. The probability of bleeding at 3 years of follow-up was significantly higher in poor responders (41%) than in good responders (7%; P = .0008). No patient reaching an HVPG of 12 mm Hg or less during treatment had variceal bleeding during follow-up. Cox's regression analysis showed that poor hemodynamic response was the main factor predicting bleeding (, = 1.91; SE(,) = 0.80; P = .01). During follow-up 11 patients died of hepatic causes. Survival was related to Child-Pugh class and to initial value of HVPG, according to Cox's analysis. In conclusion, the assessment of hemodynamic response to drugs in terms of HVPG is the best predictor of efficacy of prophylaxis of variceal bleeding in patients treated with beta-blockers or beta-blockers plus nitrates. [source] Italian experience of pediatric liver transplantationPEDIATRIC TRANSPLANTATION, Issue 7 2007Graziella Guariso Abstract:, The SIGENP Group has created an Italian Liver Transplantation database. The study considers all patients under 18 yr of age on the waiting list or transplanted between 1984 and 2005. Demographic and clinical data were collected and a descriptive analysis was conducted. Kaplan,Meier survival curves were calculated and Cox's proportional-hazards regression analysis were performed to identify predictors of death after transplantation. Twenty-two Italian centers took part and data were collected on 622 cases: only 53.8% of the transplants performed up until 1998 were carried out in Italy, while this was true of 97.7% of the operations performed between 1999 and 2005. Recipient survival curve analysis revealed one-, two- and five-yr survival rates of 88, 87 and 84%, respectively, and a significant improvement in survival after 1998 (p = 0.0322). Cox's analysis identified the following risk factors for death after liver transplantation, i.e. transplantation before 1998, neoplasms or fulminant hepatic failure as indications, being in intensive care at the time of transplantation and retransplantation. The center where the transplant is performed also revealed an influence on patient survival. Thanks to a better patient follow-up and more cooperation between specialists, the mean survival after liver transplantation is improving and Italian children can be transplanted in Italy. [source] | |||||||||||||||||||||||||