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PubMed1992

Questionable resection for carcinoma of the esophagus involving the trachea, bronchus and/or aorta--a comparative and multivariate analysis.

Controversy remains over the comparative efficacy and subsequent prognosis of resections for carcinomas of the esophagus involving the trachea, bronchus, and/or aorta. Results of a multi-variate analysis are reported using clinical data from 103 cases from 1981 to 1987. Based on the survival-rate curves according to the Kaplan-Meier method, resection was superior to non-resection. However, when other prognostic factors were adjusted using Cox's proportional hazards linear model, there was no significant difference between the resection and non-resection groups. This analysis indicates that esophagectomy is not necessarily the best approach for carcinoma of the esophagus involving these adjacent organs, although it must be remembered that resection provides excellent palliation.

Aged↗

PubMed1990

[Multivariate analysis for the study of craniofacial structure. Selection of parameters on using the principal component analysis].

The present study was undertaken to discuss the effects of parameters on using the principal component analysis for the evaluation of the craniofacial structures. Materials consisted of lateral roentgenocephalograms of 100 adult Japanese females. They were divided into three groups by ANB angle. Linear and angular measurements were selected as parameters to apply the principal component analysis, and scattergrams made by the first and second principal component were compared. The results of the analysis were varied by the parameters. Especially there was a great difference between the real size and the value corrected by isometric method on scattergrams made by the first and second components. Results indicated the importance of using appropriate parameters for the research purpose.

Adult↗

PubMed2006

Predictors of success after laparoscopic gastric bypass: a multivariate analysis of socioeconomic factors.

BACKGROUND: Laparoscopic gastric bypass (LGB) has proven efficacy in causing significant and durable weight loss. However, the degree of postoperative weight loss and metabolic improvement varies greatly among individuals. Our study is aimed to identify independent predictors of successful weight loss after LGB. METHODS: Socioeconomic demographics were prospectively collected on patients undergoing LGB. Primary endpoint was percent of excess weight loss (EWL) at 1-year follow-up. Insufficient weight loss was defined as EWL or=52.8%. According to this definition, 147 patients (81.7%) achieved successful weight loss 1 year after LGB. On univariate analysis, preoperative BMI had a significant effect on EWL, with patients with BMI <50 achieving a higher percentage of EWL (91.7% vs 61.6%; p = 0.001). Marriage status was also a significant predictor of successful outcome, with single patients achieving a higher percentage of EWL than married patients (89.8% vs 77.7%; p = 0.04). Race had a noticeable but not statistically significant effect, with Caucasian patients achieving a higher percentage of EWL than African Americans (82.9% vs 60%; p = 0.06). Marital status remained an independent predictor of success in the multivariate logistic regression model after adjusting for covariates. Married patients were at more than two times the risk of failure compared to those who were unmarried (OR 2.6; 95% CI: 1.1-6.5, p = 0.04). CONCLUSIONS: Weight loss achieved at 1 year after LGB is suboptimal in superobese patients. Single patients with BMI < 50 had the best chance of achieving greater weight loss.

Adult↗

PubMed1996

The deleterious effect of donor high plasma sodium and extended preservation in liver transplantation. A multivariate analysis.

The aim of this study was to analyze the donor risk factors associated with second orthotopic liver transplantation (reOLT) and graft loss after OLT within 1 month. A total of 649 OLTs performed in 11 centers in Spain during the period from 1992 to 1993 were analyzed retrospectively. Eleven donor and recipient variables were studied. Biochemical evolution of the OLT, biliary and arterial complications, patient status (alive, retransplanted, or dead), and follow-up were also recorded. Bivariate study demonstrated that extended preservation ( > 12 hr) was associated with increased biliary complications (P = 0.02), and lower prothrombin time (P = 0.04). In a logistic model regression for biliary complications, ischemia > 12 hr was an independent risk factor (odds ratio = 2.2, 95% confidence interval [CI] = 1.1-4.3). The multivariate Cox proportional model of potential risk factors showed that only urgent reOLT (relative risk [RR] = 2.7, 95% CI = 1.4-5.4) was independently associated with higher 30-day mortality. Donor plasma sodium > 155 mmol/L (RR = 1.4, 95% CI = 1.0-2.2) and incompatible ABO graft (RR = 3.2, 95% CI = 1.3-7.9) were independently associated with increased rate of reOLT before 30 days. Donor plasma sodium > 155 mmol/L (RR = 2, 95% CI = 1.1-3.6) and incompatible graft (RR = 3.3, 95% CI = 1.4-8.2) were independently associated with graft loss (death or reOLT) before 1 month. We conclude that cold ischemia should be kept less than 12 hr in order to avoid biliary complications. Donors over 60 years old or with plasma sodium > 155 should be carefully evaluated before OLT.

Adolescent↗

PubMed1998

Perceptual defenses and self-rated personality disorders: a multivariate analysis.

The relationships between defense mechanisms and personality disorders were explored by means of the Defense Mechanism Test and Millon's Inventory-II in a group of 100 psychiatric nonpsychotic outpatients. Only few significant positive nonparametric correlations were found, concerning barrier isolation, intro-aggression, and lateness of the threat. Also multiple regression analysis evidenced few significant results and mostly in the negative direction. The unpredicted findings may have been partly determined by a general elevation of personality scale scores (due to the emotional distress of psychiatric), leading to a loss of interindividual differences.

Adult↗

PubMed1992

Preoperative radiation for carcinoma of the thoracic esophagus involving adjacent organs--a comparative and multivariate analysis of prognosis.

Controversy remains over the comparative efficacy and subsequent prognosis for preoperative radiation for carcinoma of the esophagus involving the trachea, bronchus, and/or aorta. Results of a multi-variate analysis are reported using clinical data from 57 cases from 1981 to 1987. Based on both the survival-rate curves using the Kaplan-Meier method and the adjusted survival-rate curves using Cox's proportional hazards linear model, there was no significant difference in prognosis between patients who received preoperative radiation and those who did not. This analysis indicates that preoperative radiation at doses of 30Gy produces no clinical advantage and therefore is not the best treatment for carcinoma of the esophagus involving these adjacent organs.

Aged↗

PubMed1995

[Multivariable analysis of survival in patients with transitional cell bladder carcinoma].

In 82 transitional cell bladder cancer patients with adequate follow-up, the prognostic value of histological grade, depth of invasion, size, site, appearance, number of primary tumours, surgical treatment and ages of patients were assessed. Univariable analysis showed the statistically significant relation of histological grade, depth of invasion, size, site, appearance and number of tumours to survival. Survival analysis with Cox's regression model indicated that the histological grade is the most important prognostic factor, followed by site of tumours and depth of invasion. The results suggest that the information of site should not be omitted.

Adult↗

PubMed1992

Exercise-induced QRS changes in healthy men and women: a multivariate analysis on their relation to background data and exercise performance.

Changes in the QRS segment during exercise have repeatedly been suggested to provide diagnostic information with respect to ischaemic heart disease, but the subject is controversial. In order to study the possibly confounding effects of gender, age, resting ECG and exercise performance, 50 healthy subjects were investigated with computerized vectorcardiography during a maximal ergometer exercise test. The overall change in the QRS complex decreased significantly with age and female gender (P < 0.001). However, these responses were better explained by baseline QRS size, change in heart rate and systolic blood pressure (adjusted r2 > 0.70, vs adjusted r2 > 0.41). Effects of age were seen in the Y-lead, and gender effects in the X- and Z-leads (P < 0.0001). In multivariate analyses, X- and Y-lead alterations correlated negatively to change in heart rate and resting QRS size (X-lead; adjusted r2 > 0.50, Y-lead; r2 > 0.44). Z-lead alterations correlated negatively with female gender and resting Z-lead QRS size (adjusted r2 > 0.31). ST changes correlated with QRS changes in the X- and Y-leads (P < 0.05). QRS changes immediately after exercise correlated with alterations during exercise (P < 0.004), maximal load (P < 0.01) and time to hypotension post-exercise (X- and Z-lead; P < 0.02). In conclusion, QRS changes appear to be related to baseline QRS size, change in heart rate and ST change, factors which may have important confounding effects. Consideration of these factors may help in resolving the controversy surrounding QRS changes.

Adult↗

PubMed1997

[Surgery of the ascending aorta: the 1984-1995 experience of the cardiac surgery teaching unit in the University of Milan. Multivariate analysis of its risk factors for hospital mortality and reduced long-term survival].

Between 1984 and 1995, 183 patients underwent an ascending aorta procedure at our institution. Their mean age was 60 +/- 12.3 years; 116 (63.4%) patients were male, 35 (19.1%) had a history of congestive heart failure, 72 (39.3%) presented acute type A dissection, 23 (12.6%) were redos and 63 (34.4%) were operated on an emergency basis. In-hospital mortality was 10% (12/120) in elective procedures and 36.5% (23/63) in emergency operations (p < 0.0001). Multivariate stepwise logistic regression analysis identified cardiopulmonary by-pass time, emergency operation, arch replacement and the need for femoral vein cannulation at surgery as independent predictors of in-hospital death. Mean follow-up time was 54 +/- 30 months (median 50 months), with a Kaplan-Meier survival of 69 +/- 4% and of 60 +/- 5% at 5 and 7 years, respectively. Cox regression analysis identified arch replacement, perioperative myocardial infarction, preoperative NYHA class, acute type A aortic dissection, the need for femoral vein cannulation at intervention and redo operations as independent predictors of reduced survival at follow-up. When this kind of analysis was performed on hospital survivors only, postoperative tracheostomy, reexploration for bleeding, and the occurrence of postoperative ventricular arrhythmias emerged as risk factors. In conclusion, multiple factors affect both early and long-term outcome following ascending aorta surgery. Preoperative clinical status of patients, priority of surgery and aortic dissection are the main determinants of the short-term results. Otherwise, in hospital survivors, the main determinant for long-term outcome seems to be the immediate postoperative course.

Aged↗

PubMed1991

Pathogenetic role of Helicobacter pylori in duodenal ulcer disease. Multivariate analysis of factors affecting relapse.

The pathogenesis of duodenal ulcer disease is multifactorial and the contribution of Helicobacter pylori in relation to the other factors to the release of duodenal ulcer is unknown. To investigate this, we studied 147 patients with endoscopically proven healed ulcers. These patients were randomized to receive either placebo, misoprostol 200 micrograms or misoprostol 300 micrograms four times daily, and clinical, personal, physiological and endoscopic characteristics were obtained prospectively. Endoscopy was performed at the active phase of the ulcer and when the ulcer healed. Biopsies were taken from the antrum to assess histologically for: (1) the activity of gastritis as assessed by the degree of polymorph infiltration, (2) the degree of chronic inflammation by the degree of chronic inflammatory cells infiltration and degree of mucosal degeneration, and (3) bacteriologically for the presence of H. pylori. The severity of the gastritis and the bacterial density were graded independently by two pathologists. The patients were assessed at two-month intervals for 12 months or until the ulcer relapsed. The results demonstrated that the relapse rates of duodenal ulcer were similar in the three treatment groups. The relapse rate was higher in the group with higher density of the bacteria (P less than 0.05). The degree of gastritis did not affect the relapse rate of duodenal ulcer in either the placebo or misoprostol group or in all patients combined. Stepwise logistic regression analysis identified that increased duodenal inflammation, male sex, early-onset disease, and H. pylori adversely affected relapse of the ulcer. We conclude that multiple factors affect the relapse of duodenal ulcer and H. pylori is one of them.

Adult↗

PubMed2005

Classifying honeys from the Soria Province of Spain via multivariate analysis.

A total of 73 different honeys from seven botanical origins [ling (Calluna vulgaris L.), heather (Erica sp.), rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris L.), honeydew (Quercus sp.), spike lavender (Lavandula latifolia M.) and french lavender (Lavandula stoechas L.)] have been classified by applying discriminant analysis to their metal content data and other common physicochemical parameters. Fifteen minerals were identified and quantified using atomic emission spectroscopy (AES) for K and Na, and inductively coupled plasma atomic emission spectrometry (ICP-AES) for Mg, Ca, Al, Fe, Mn, Zn, B, Cu, Co, Cr, Ni, Cd and Pb. Moreover, eight physicochemical parameters were analysed following the Harmonised Methods of the International Honey Commision: ash content, moisture, insoluble matter, reducing sugars, apparent sucrose, diastase activity, free acidity and hydroxymethylfurfural. The honeys analysed were characterised and distinguished using chemometrics. ANOVA highlighted significant differences between the honeys in terms of the mean contents of all variables except apparent sucrose, HMF, Fe and Zn. Principal component analysis was used as a descriptive tool to visualise the data structure in two dimensions, finding relationships between variables and types of honey. Likewise, discriminant analysis, together with various methods (stepwise, forward and backward), was used to select the variables with the highest discriminating power, which allowed us to classify all of the botanical origins considered in this work, achieving a global success rate close to 90% following cross-validation.

Honey↗

PubMed1996

Multivariate analysis of capillary electrophoresis separation conditions for Z-E isomers of clomiphene.

Plackett-Burman (P-B) experimental design has been used to optimize the factors affecting separation of Z and E isomers of clomiphene (zuclomiphene and enclomiphene respectively) using capillary electrophoresis. The P-B design was used to simultaneously investigate the following five factors: buffer ionic strength, buffer pH, heptakis (2,3,6-tri-o-methyl) beta-cyclodextrin (TMCD) concentration, methanol concentration and injection time, each at three levels. In addition to these, a dummy variable was added to estimate the variability of the system. Effects on resolution and analysis time were calculated. Based on the information gained from the P-B design, the following set of conditions was chosen: 100 mM phosphate buffer pH 2.3, 5 mM TMCD, 5% methanol, and 1.7 s hydrodynamic injection time. These conditions gave well-resolved peaks for zuclomiphene and enclomiphene.

Clomiphene↗

PubMed2005

Original and reviewed nuclear grading according to the Fuhrman system: a multivariate analysis of 388 patients with conventional renal cell carcinoma.

BACKGROUND: The objective of the current study was to evaluate the reproducibility of the Fuhrman nuclear grading system as well as its independent predictive value in a series of patients with conventional renal cell carcinoma (RCC). METHODS: The authors selected 388 patients who had undergone surgical treatment for conventional RCC between 1986 and 2000. Pathology slides from the selected patients were reviewed by a single pathologist, who reassigned a Fuhrman nuclear grade and assessed the presence of tumor necrosis. The pathologist was blinded to both the original pathologic diagnosis and follow-up data. The kappa statistic was used to evaluate concordance between original and reviewed nuclear grades. The log-rank test was used for univariate analyses, and a Cox proportional hazards model was used for multivariate analyses. RESULTS: The original Fuhrman nuclear grade was Grade 1 (G1) in 111 patients (28.6%), G2 in 141 patients (36.3%), G3 in 108 patients (27.8%), and G4 in 28 patients (7.3%). After pathology slide review, nuclear grades were reassigned as follows: G1 in 49 patients (12.6%), G2 in 138 patients (35.6%), G3 in 150 patients (38.7%), and G4 in 51 patients (13.1%). The grade of concordance was moderate (kappa=0.44; P <0.001). Univariate analyses identified three separate prognostic categories defined by nuclear grade (G1 and G2 vs. G3 vs. G4). Both the original and the reviewed Fuhrman nuclear grading systems were capable of independently predicting disease-specific survival in patients with conventional RCC. CONCLUSIONS: The interobserver reproducibility of Fuhrman nuclear grading was moderate. The substantial overlap in survival curves for G1 and G2 tumors provided an opportunity to cluster those categories, and the resulting three-tiered nuclear grading system was an independent predictor of cause-specific survival in patients with conventional RCC. Other independent predictors of survival included pathologic stage and tumor necrosis status.

Adult↗

PubMed2000

Multivariate analysis in skull osteometry of the common tree shrew from both sides of the Isthmus of Kra in Southern Thailand.

The Isthmus of Kra in Southern Thailand consists of a lowland of about 70 km in length. It has been suggested that the Isthmus may sink beneath the sea surface according to the change of level of the sea, and may function as a zoogeographical barrier in land mammals in this region. So, the geographical variation was osteometrically examined in skull of the common tree shrew (Tupaia glis) from the both sides of Isthmus of Kra. The osteometrical examination demonstrated that the skull is larger in southern population than in northern one. In the charts of the principal component analysis, however, the morphological separation between two populations can not be obviously seen in female. While, the results of the discriminant analysis indicated the morphological separation between the two populations. These findings suggest that the zoogeographical barrier of Isthmus of Kra may have influence on the osteometrical variation in the common tree shrew, when the Isthmus was covered with sea.

Animals↗

PubMed2005

Safety, effectiveness, and patterns of use of olanzapine in acute schizophrenia: a multivariate analysis of a large naturalistic study in the hospital setting.

BACKGROUND AND OBJECTIVE: This study assessed the safety and effectiveness of the atypical antipsychotic olanzapine for the treatment of inpatients with acute schizophrenia. Furthermore, we evaluated patterns of use of olanzapine and their relationship to safety and effectiveness. PATIENTS AND METHOD: This was a prospective, comparative, nonrandomized, open-label, observational study of 848 patients with schizophrenia (International Classification of Diseases, 10th edition) hospitalized due to an acute psychotic episode. Data were collected during patients' entire hospital stay. Safety of antipsychotic therapy was assessed with an extrapyramidal symptoms questionnaire (based on the Udvalg for Kliniske Undersøgelser scale) and the report of spontaneous adverse events. Clinical status was assessed with the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impressions-Severity of Illness (CGI-S). A multivariate statistical approach was employed. RESULTS: Patients treated with olanzapine in monotherapy had the lowest risk of developing extrapyramidal symptoms (11.2%), whereas patients treated with conventional antipsychotics had a higher risk (39.0%; p < 0.001). Patients treated with olanzapine in monotherapy (even patients with prominent positive symptoms) displayed a higher rate of response compared with conventional antipsychotics-treated patients (p = .007). CONCLUSIONS: Olanzapine is a safe and effective treatment for patients with acute schizophrenia in the hospital setting, even for patients with prominent positive or agitation symptoms.

Acute Disease↗

PubMed2002

Prognostic factors of hepatic resection for hepatocellular carcinoma with cirrhosis: univariate and multivariate analysis.

BACKGROUND AND OBJECTIVES: The objective of this investigation was to study the clinicopathological factors influencing long-term outcome of hepatocellular carcinoma (HCC) with liver cirrhosis in patients undergoing hepatectomy. Liver cirrhosis, especially the macronodular variety, has been found in up to 90% of patients with HCC. In Asia, the incidence of liver cirrhosis in patients with HCC who had undergone hepatic resection varies from 42.5% to 73.8%. However, the optimal surgical approach for HCC patients with cirrhosis is less clearly defined. Resection of the cirrhotic liver is challenging and remains controversial in the treatment of HCC. METHODS: This study retrospectively analyzed the surgical outcomes of HCC concomitant with liver cirrhosis in 218 patients who underwent hepatic resection between 1986 and 1998. Post-resection prognostic factors were assessed using a univariate log-rank test and a multivariate Cox proportional hazards model. RESULTS: The overall postoperative complication rate was 15.6%, while the surgical mortality rate was 8.8%. Meanwhile, the 1-, 3-, and 5-year disease-free survival rates were 50.9%, 33.98%, and 27.03%, respectively, and. the overall cumulative survival rates at 1, 3, and 5 years were 63.14%, 41.88%, and 31.83%, respectively. Applying Cox's multivariate proportional hazard model indicated that significant adverse prognostic indicators included elevated alkaline phosphatase value, tumor size >2 cm, presence of satellite lesions, and vascular invasion. CONCLUSIONS: This investigation found that overall survival for HCC patients concomitant with liver cirrhosis who underwent hepatic resection should be stratified on the basis of the high value of alkaline phosphatase, tumor size, satellite lesions, and vascular invasion.

Adolescent↗

PubMed2004

Prognostic factors for survival of patients after curative surgery for renal cell carcinoma: multivariate analysis of 482 cases.

BACKGROUND: Even with curative surgery, renal cell carcinoma occasionally recurs in other organs, with fatal results. In this study, we identified independent prognostic factors for survival in patients with renal cell carcinoma after curative surgery. METHODS: The records of 482 patients (mean age, 61.0 years; range, 17-90 years) who underwent curative surgery for renal cell carcinoma at Gifu University Hospital and its affiliated hospitals between 1991 and 2000 were reviewed. The average follow-up period was 42 months (range, 10-140 months). Clinical characteristics of the 482 patients were divided into three categories: patient factors (sex, age, performance status, and mode of tumor discovery), tumor factors (T classification, N classification, mode of infiltration, histological grade, and venous invasion), and treatment factor (whether or not adjuvant therapy with interferon-alpha was used). Stepwise multivariate Cox proportional hazards regression modeling was performed to identify independent determinants of survival. RESULTS: Of the patient factors, performance status and mode of tumor discovery were independent factors predicting survival. Of the tumor factors, venous invasion and mode of infiltration were independent factors predicting survival. Use or non-use of adjuvant therapy was not significantly associated with survival. Overall, performance status, venous invasion, mode of infiltration, and histological grade were shown to be independent prognostic factors, in descending order of importance. CONCLUSION: Performance status, venous invasion, mode of infiltration, and histological grade, in descending order, were the most important factors predicting survival after curative surgery for renal cell carcinoma.

Adolescent↗

PubMed2001

Retrospective multivariate analysis of hepatic veno-occlusive disease after blood or marrow transplantation: possible beneficial use of low molecular weight heparin.

This retrospective cohort study of 462 consecutive adult allogeneic and autologous blood or marrow transplantation (BMT) patients compared the incidence of hepatic veno-occlusive disease (VOD) after BMT with three prophylactic regimens. Patients receiving heparin (Hep), heparin + prostaglandin E1 (Hep + PGE1) or low molecular weight heparin (LMWH) as a prophylactic VOD regimen were compared to a historical cohort receiving no VOD prophylaxis. Of 462 BMT patients, VOD was diagnosed in 22% (31 of 142) of the no prophylaxis group, 11% (11 of 104) of the Hep, 12% (13 of 110) in the Hep + PGE1 and 4% (four of 106) of the LMWH group (P = 0.0002). VOD was the primary cause of death in 20% (12 of 59). By multivariate logistic regression, independent risk factors for developing VOD were: no VOD prophylactic regimen, unrelated allogeneic BMT, Karnofsky performance score (KPS) < 80 and aspartate aminotransferase (AST) > or =50 U/l. There was no increase in the rate of death due to hemorrhagic events or VOD in any prophylaxis group compared to the control group. Prospective randomized trials of Hep vs LMWH vs placebo are warranted to assess the efficacy of heparin compounds in the prevention of VOD.

Adult↗