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Results for “multivariate analysis”

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PubMed1992

Bronchopleural fistulas associated with lung cancer operations. Univariate and multivariate analysis of risk factors, management, and outcome.

During a 28-year period, 52 bronchopleural fistulas developed after pulmonary resection of 49 primary and three recurrent lung cancers at the National Cancer Center Hospital, Tokyo. During the same period there were 2359 pulmonary resections for primary lung cancer; the prevalence of bronchopleural fistula was 2.1%. Multivariate analysis on 15 variables in the most recent 1360 resections revealed significant risk factors for bronchopleural fistula: wider resection such as pneumonectomy, residual carcinomatous tissue at the bronchial stump, preoperative irradiation, and diabetes. Univariate analysis further recognized a risk in preoperative bronchial arterial infusion and the postsurgical stage of lung cancer. Six patients were not treated. Apart from chest tube drainage in seven patients, surgical repair was attempted in 39, direct resuture of the stump in 16, wrapping in 25, thoracoplasty in 31, completion pneumonectomy in 6, and other treatments. Despite various treatments, 37 patients (71.2% mortality) died from fistula-related complications (such as regurgitation of infected pleural fluid through the fistula and airway/intrathoracic bleeding). Even for patients whose fistulas were cured and who were discharged, the average hospital stay was 189 days. Further investigation is necessary to answer whether prevention by flap coverage is of any benefit.

Adult↗

PubMed1991

[Multivariate analysis on factors associated with preterm delivery].

In order to estimate the occurrence of Preterm Delivery (PD) and factors associated with PD, 1141 perinatal cases at first affiliated hospital were collected by the method of systematic random sampling. The occurrence rate of PD was 6.0%. Multivariate analysis revealed that the history of premature birth, twin pregnancy, polyhydramnios, placenta praevia, premature rupture of fetal membranes and Bart's fetal hydrops were the main risk factors with statistical significance. Path analysis showed that the history of premature birth had indirect positive effect (elevating risk of PD) on PD through premature rupture of the fetal membranes and Bart's fetal hydrops. Similarly, twin pregnancy had indirect positive effect through premature rupture of the fetal membranes and polyhydramnios. It is suggested that proper health care of the pregnant mother attending to the risk factors should be emphasized to prevent the occurrence of PD.

China↗

PubMedDate not supplied

Multivariate analysis of factors predicting outcome after laparoscopic Nissen fundoplication.

Laparoscopic Nissen fundoplication has been applied with increasing frequency in the treatment of gastroesophageal reflux disease. The aim of this study was to determine the variables that predict outcome of laparoscopic Nissen fundoplication. A multivariate analysis was performed on data from 199 consecutive patients undergoing laparoscopic Nissen fundoplication. Variables included age, sex, body mass index, primary symptoms, clinical response to acid suppression therapy, erosive esophagitis, 24-hour esophageal pH score, and the percentage of time the esophageal pH was less than 4 on 24-hour pH monitoring, lower esophageal sphincter competence, status of the esophageal body motility, hiatal hernia, carditis, intestinal metaplasia of cardiac epithelium limited to the gastroesophageal junction, and Barrett's esophagus of any length. Clinical outcome was obtained from all patients at a median follow-up of 15 months (range 6 to 74 months) after surgery. One hundred seventy-three patients had an excellent or good outcome (87%) and 26 had a fair or poor outcome. Three factors were significantly predictive of a successful outcome: an abnormal 24-hour pH score (odds ratio = 5.4; 95% confidence interval [CI] = 1. 9-15.3), a typical primary symptom (odds ratio = 5.1; 95% CI = 1. 9-13.6), and a clinical response to acid suppression therapy (odds ratio = 3.3; 95% CI = 1.3-8.7). We conclude that 24-hour pH monitoring provides the strongest outcome predictor of laparoscopic Nissen fundoplication and that outcome is based more on the correct identification of the disease than on its severity.

Adolescent↗

PubMed1987

Study of circadian correlations between acetylcholine muscarinic receptor and brain glycosyltransferases by multivariate analysis.

Circadian variations of the acetylcholine muscarinic receptor and some glycosyltransferases were studied in brain using multivariate analysis. Highly significant correlations exist between fucosyltransferase, sialyltransferase and galactosyltransferase and to a lesser extent between both of these enzymes and acetylcholine receptor. No correlation appeared between these enzymes and dolichol phosphate mannose synthase.

Analysis of Variance↗

PubMed1987

Semen parameters and fertilization of human oocytes in vitro: a multivariable analysis.

Semen parameters in 195 couples undergoing in vitro fertilization and embryo transfer were studied using multivariable analysis. Semen parameters that correlated most closely with reduced ability to fertilize apparently mature oocytes were a slow rate of foreward progression of sperm and the presence of excess numbers of white cells in semen. In men with semen parameters within the normal range, the hamster egg penetration assay (HEPA) test did not add additional predictive power. In men with suspected semen abnormalities, however, a low attachment rating added some, but minimal, predictive value. None of the predictive methods reported thus far in this or other studies offers sufficient accuracy to reliably identify the men who will prove infertile for in vitro fertilization treatment.

Analysis of Variance↗

PubMed1989

A multivariate analysis of preoperative risk factors in patients with common bile duct stones. Implications for treatment.

A multivariate analysis of 30 preoperative risk factors was undertaken in 248 patients who underwent surgery alone for common bile duct (CBD) stones and in 190 patients who had endoscopic sphincterotomy (ES), 77 of whom subsequently also had surgery. Independently significant risk factors in those undergoing surgery were the serum bilirubin level, the use of preoperative ES, and the presence of medical risk factors; in patients undergoing ES, only the serum bilirubin and albumin, but not medical risk factors, were of independent significance. The major implications of this study are, first, that high-risk patients should be treated by ES without subsequent surgery, and second, that "fit patients should be treated by surgery alone without routine preoperative ES.

Adult↗

PubMed1989

[Prediction of true and false positive responses to exertion by a second exercise under sublingual nitroglycerin. Multivariate analysis].

The authors consider that the diagnostic value of exercise tests could be improved by a multivariate analysis integrating the ergometric data of two exercise tests: a reference test and a test performed under nitroglycerin. 109 patients without previous myocardial infarction who suffered from angina-like chest pain were explored. All had an ischaemic-type ST depression on the CM5 lead during the first exercise test and were tested again after sublingual administration of nitroglycerin. Both tests were continued until the theoretical maximum heart rate was reached or symptoms were no longer bearable. Coronary arteriography showed that 27 patients had normal coronary vessels and 82 had a coronary disease. At univariate analysis, two parameters were significant in predicting coronary disease. These were an in increase, between the two tests, of maximal work performed (from 95 +/- 1578 kpm to 2085 +/- 1662 kpm, p less than 0.001) and of the double product, i.e. maximum heart rate x maximum systolic arterial pressure (from 181 +/- 5289 to 3826 +/- 4245 mmHg.b.min-1, p less than 0.001). Five variables were selected by logistic regression analysis, viz.: change in ST depression between the two tests, double product during the first test, sex, modification of work performed between the two tests and occurrence of chest pain during the first test. By using a threshold analysis (less than 20 p. 100, greater than 80 p. 100), 76 p. 100 of the population was correctly classified; 82.9 p. 100 of coronary disease patients and 53 p. 100 of normal subjects were well classified, whereas 2.7 p. 100 of the population studied (all normal subjects) were erroneously classified.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Sublingual↗

PubMed1993

The significance of methicillin-resistant Staphylococcus aureus infection in general surgery: a multivariate analysis of risk factors and preventive approaches.

To investigate the characteristics, risk factors, and prevention of methicillin-resistant Staphylococcus aureus (MRSA), a total of 3,627 patients were studied. Among these, 1,336 patients with various infections were used in a risk factor analysis of MRSA to determine the relationship between the use of antibiotics and the incidence of MRSA. Only 3.0% of infections were attributed to MRSA, the esophagus and colorectal region being highly involved, as anastomotic or pelvic abscesses, while the lung had a lower incidence. Almost half the patients with MRSA infections (47.6%) had concomitant infection. A univariate analysis revealed the following significant factors: The coexistence of gastrointestinal or metastatic malignancy, sepsis, tracheostomy, and the prior use of antibiotics such as the beta-lactam compounds or aminoglycosides. A multivariate analysis showed that gastrointestinal malignancy, sepsis, and the prior use of aminoglycosides, tetracycline, macrolides, and carbapenems were independently significant factors. To promote the education of doctors and nurses, regular in-service meetings on MRSA were held in the ward. Moreover, preventive approaches such as patient isolation, strategically placed hand washing equipment, and the use of disposable gloves and contaminated waste bags, have been initiated, and the incidence of MRSA has decreased significantly since then. Thus, to control MRSA, the following steps should be taken: (1) constant and careful surveillance, (2) regular risk factor analyses, (3) the optimal administration of antibiotics, and (4) the education of all hospital staff.

Cross Infection↗

PubMed1991

The effect of mass screening for breast cancer: results of a multivariate analysis.

To evaluate the life-prolonging effect of mass screening for breast cancer, we compared the risk of death for the patients detected by mass screening with that for the patients diagnosed in out-patient clinics, after adjusting for other relevant factors simultaneously by using the Cox regression model. A multivariate analysis using the Cox regression model in which clinical staging of disease was taken as one of the independent variables, showed that the risk of death for patients detected by mass screening was smaller by 0.765 times than that for patients found in out-patient clinics although the reduction was not statistically significant. This small reduction might be partly due to the effect of mass screening through early detection even within the same stage, and partly due to length bias, lead time bias and self-selection bias. When clinical staging of disease was removed from the independent variables, the risk of death for patients detected by mass screening was reduced from 0.765 times to 0.677 times that for patients diagnosed in out-patient clinics, which was statistically significant (P greater than 0.01). For asymptomatic patients detected by mass screening, such as reduction of the risk of death was from 0.789 times to 0.555 times that for patients found in out-patient clinics (P less than 0.05). These results suggest that mass screening for breast cancer may contribute to the reduction of the risk of death, although the effect of biases inherent in periodic screening was not removed completely in the present analysis.

Breast Neoplasms↗

PubMed1994

Role of clinical criteria in the diagnosis of hereditary non-polyposis colorectal cancer (HNPCC): results of a multivariate analysis.

Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant disease characterized by early-onset colorectal tumors, primarily in the right colon, that are frequently associated with other cancers. In the absence of a reliable biomarker, clinical criteria for diagnosing HNPCC have been proposed by the International Collaborative Group on HNPCC (ICG-HNPCC). However, these criteria are often too restrictive for application in small families. We analyzed 6 clinical/pathological features suggestive of genetic colon-cancer risk in 970 colorectal-cancer patients defined according to the ICG criteria as HNPCC (96) or non-HNPCC (874). Logistic regression analysis was used to determine their relative potentials for predicting the diagnosis of HNPCC. The most predictive were then used to estimate HNPCC risk levels within the non-HNPCC group. Multivariate analysis showed the following associations with HNPCC diagnosis: vertically transmitted cancer ("highly predictive"), early-onset (< 50 yrs) colorectal cancer, aggregation of tumors in the nuclear pedigree and proximal-colon tumors (the last 3 considered "predictive"). Re-evaluation of all families revealed that 76 non-HNPCC families (8.9% of the whole series) satisfied our highly predictive vertical-transmission criterion plus at least one of the other "predictive" criteria. The presence of 2 consecutive generations affected by colorectal cancer or early primaries seems to be a major risk indicator of hereditary colorectal cancer. Using this approach we identified a large group of families that require further evaluation, although they do not currently meet the ICG-HNPCC criteria for HNPCC.

Colorectal Neoplasms, Hereditary Nonpolyposis↗

PubMed2006

Multivariate analysis approach to the plasma protein profile of patients with advanced colorectal cancer.

The aim of the present study was to identify the pattern of plasma protein species of interest as markers of colorectal cancer (CRC). Using matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS), the plasma protein profile was determined in nine stage IV CRC patients (study group) and nine clean-colon healthy subjects (control group). Multivariate analysis methods were employed to identify distinctive disease patterns at protein spectrum. In the study and control groups, cluster analysis (CA) on the complete MALDI-MS spectra plasma protein profile showed a distinction between CRC patients and healthy subjects, thus allowing the identification of the most discriminating ionic species. Principal component analysis (PCA) and linear discriminant analysis (LDA) yielded similar grouping results. LDA with leave-one-out cross validation achieved a correct classification rate of 89% in both the patients and the healthy subjects.

Adenocarcinoma↗

PubMed1992

Multivariate analysis by the minimum spanning tree method of the structural determinants of diphenylethylenes and triphenylacrylonitriles implicated in estrogen receptor binding, protein kinase C activity, and MCF7 cell proliferation.

The response profiles of 36 para-substituted diphenylethylenes (DPEs) and triphenylacrylonitriles (TPEs) have been compared by multivariate analysis. The responses measured were (a) relative binding affinity (RBA) for the cytosol estrogen receptor (ER), (b) ability to promote the growth of the human MCF7 breast cancer cell-line, (c) cytotoxicity in MCF7 cells, and (d) ability to stimulate or inhibit protein kinase C (PKC) III activity under three different conditions of enzyme activation. The prime object of the analysis was to observe the simultaneous influence of diverse combinations of substituents on all these in vitro responses. To do this, the minimum spanning tree (MST) method was used to organize the molecules into a network in which proximate molecules are closely related with regard to their responses whereas remote molecules are distinct. The MST of this population of molecules had four main branches. E2 and its TPE mime were located in a central position within the trunk whereas the tips of the branches tended toward molecules of different specificity, i.e., cytotoxic molecules that bind to ER and interfere with PKC, noncytotoxic molecules that also bind to ER and interfere with PKC but promote cell growth, molecules only active on PKC, and molecules active on all parameters except PKC stimulation. A parallel MST analysis of the relationships among the response parameters themselves confirmed previous conclusions: For this population of molecules, RBAs for ER are fairly closely related to ability to promote MCF7 cell growth and only little to cytotoxicity (Bignon et al. J. Med. Chem. 1989, 32, 2092). Cytotoxicity is much more clearly correlated with inhibition of diacylglycerol-stimulated PKC activity than with RBAs for ER. PKC inhibition differs substantially depending upon whether the substrate is H1 histone or protamine sulfate.

Acrylonitrile↗

PubMed2001

Determination of energetic materials in soil using multivariate analysis of Raman spectra.

Contamination of soils by energetic materials (EMs) is an important issue in many locations (such as test mounds, ordnance depots, and manufacturing sites). Raman spectroscopy can be useful as a screening technique at the percent level (by mass) if interference from soil fluorescence can be overcome. Multivariate analysis is shown capable of both extracting the Raman signatures of EMs from spectra obscured by large fluorescence backgrounds caused by soil components, and generating calibration curves for the EMs at the percent level.

Multivariate Analysis↗

PubMed2000

Multivariate analysis of prognostic factors in patients with refractory and relapsed acute myeloid leukemia undergoing sequential high-dose cytosine arabinoside and mitoxantrone (S-HAM) salvage therapy: relevance of cytogenetic abnormalities.

To improve the basis for the stratification of patients with refractory and relapsed acute myeloid leukemia (AML) univariate and multivariate analyses of prognostic factors were performed in 254 patients (median age 50 years, range 18-74) undergoing S-HAM salvage chemotherapy during two consecutive prospective trials of the German AML Cooperative Group. In a multivariate analysis, duration of the first complete remission (CR) was the only factor associated with time to treatment failure (P = 0.0223). Disease-free survival was influenced by a short duration of the first CR of less than 6 months (P = 0.0001), WBC (P = 0.0018), blast count (P = 0.0037), and neutrophil count (P = 0.0119). The achievement of CR was related to the hemoglobin level only (P = 0.0457), the early death rate was related to age only (P = 0.0109), and survival was related to the bilirubin level only (P = 0.0166). In the subgroup of 104 patients in whom additional karyotype analyses were performed prior to first-line therapy unfavorable chromosome abnormalities were associated with a lower CR rate (univariate analysis, P = 0.0342; CR 24% vs 53%) and were the only factor related to survival. These analyses warrant the further evaluation of the impact of cytogenetic abnormalities on the outcome of patients with advanced AML in order to improve the characterization according to duration of first CR and to WBC of distinct subgroups of patients with differing prognoses as a basis for stratification in future trials.

Adult↗

PubMed1991

Ventricular conduction defects and atrial fibrillation after coronary artery bypass grafting. Multivariate analysis of preoperative, intraoperative and postoperative variables.

Preoperative, intraoperative and postoperative variables, which might play a role in the development of ventricular conduction defects (VCD) and atrial fibrillation (AF) following coronary artery bypass grafting (CABG), were evaluated in 236 consecutive patients. VCD and AF developed postoperatively in 15.5% of patients: 4.5% had VCD (subgroup A), 11.0% had AF (subgroup B). In 84.5% of patients VCD and AF did not occur (subgroup C). Univariate analysis showed statistically significant differences between subgroups A and C with respect to: left main significant stenoses and number of diseased vessels. Bypass pump time and aortic cross-clamp time were significantly longer in subgroup B. Multivariate analysis showed a significantly greater incidence of left main disease and of right coronary artery occlusion associated with significant stenosis of the proximal left anterior descending artery in subgroup A. In subgroup B, the duration of aortic cross-clamp time was significantly higher. Ischaemic injury, with increasing duration of cardioplegic arrest, seems to play a key role in the development of AF. Nonhomogeneous cardioplegic delivery to critical areas of myocardium, and particularly to the specialized conducting system, may cause VCD after CABG.

Adult↗

PubMed2002

Evaluating the heavy metal contamination in sediments from the guadalquivir estuary after the Aznalcóllar mining spill (SW Spain): a multivariate analysis approach.

The Doñana National Park is one of the most important Natural Reserves in west Europe. The park and the Guadalquivir estuary were impacted by the release of 5 million cubic meters of acid waste from the processing of pyrite ore. Here are presented a multivariate analysis approach to evaluate the extension and the magnitude of the accidental spill on the estuarine sediments. Sediments were used to analyze 6 different metals (Fe, Mn, Zn, Cd, Pb, Cu). Also the concentration of the metals in the different geochemical sediment fractions were determined as a means of assessing the potential impact of the acid water from the mine. The analysis of the results obtained permits to establish that the impact of the accident was acute on the ecosystem due to the set up of a treatment plan in June 1998 and to the high hydrodynamic of the estuary that absorb the early impact. Chronic contamination by Cu was also detected during the monitoring of the impact of the accident in the estuary but this did not appear to be related to the accidental spill. Because the likelihood of long term adverse effects from the heavy metal contamination of estuarine sediments, further ecotoxicological evaluations should be carried out for the estuary and the park using an integrated approach.

Accidents, Occupational↗

PubMed1993

Carcinoembryonic antigen (CEA) in stage IV gastric cancer as a risk factor for liver metastasis: a univariate and multivariate analysis.

Serum carcinoembryonic antigen (CEA) levels were determined in 68 patients with Stage IV gastric cancers, the objective being to examine the clinicopathological relationship between the metastatic patterns of gastric cancer and the serum CEA level. Of the 68 patients, 31 were diagnosed as cases of liver metastases and 37 as cases of peritoneal dissemination. Serum CEA levels were elevated in 21 of 31 patients (67.8%) with liver metastases and in 7 of 37 patients (18.9%) with peritoneal dissemination (P < 0.01). A univariate analysis showed that liver metastasis correlated with a young age (P < 0.01), the lower portion of stomach (P < 0.05), Borrmann types 1 and 2 (P < 0.01), differentiated type (P < 0.01), and nonserosal involvement (P < 0.05) more than did peritoneal dissemination. A multivariate analysis showed that in addition to Borrmann type 1 and 2, elevated CEA levels (> 2.5 ng/ml) is an independent risk factor involved in liver metastasis. Thus careful follow-up and postoperative adjuvant therapy are required for patients with elevated CEA levels, even with "curative" resection.

Adult↗

PubMed1994

Multivariate analysis of prognostic parameters using interstitial thermoradiotherapy (IHT-IRT): tumor and treatment variables predict outcome.

PURPOSE: From January 1986 to October 1991, 90 patients with localized tumors were treated in a Phase I/II trial using low-dose 192Ir brachytherapy (IRT) plus interstitial 915 MHz microwave (MW) hyperthermia (IHT) and external beam radiotherapy (ERT). Tumors were classified as locally advanced primary (class 1: 27), recurrent (class 2: 40), metastatic (class 3: 10) and persistent (class 4: 13) lesions. The treatment sites included tumors of the head and neck (62), pelvis (26), and others (2). The mean cuboidal tumor volume was 63 cm3 (range: 8-288 cm3). Most recurrent and metastatic lesions (48) had received prior treatment including ERT. METHODS AND MATERIALS: The treatment protocol prescribed two heating sessions (each 60 min) at 41-44 degrees C before and after IRT. One hundred sixty-one IHT sessions were evaluated. Invasive thermal data were recorded at an average of 18 sites throughout the implant volume. Several thermal variables were analyzed (e.g., averaged parameters: Tmaxav, Tmean, Tminav; index parameters: T10, T50, T90). The study was evaluated with a minimum follow up (FU) of one year. Median follow-up was 19 months. RESULTS: At 3 months FU, a complete response (CR) was observed in 59 of 90 (66%) patients. At 12 months FU, local control (LC) was achieved in 54 of 84 (64%) evaluable patients. Ten patients developed a local and 14 a regional recurrence (REC) after achieving a CR and/or LC. At last FU, a total of 31 (34%) patients were still alive and 28 (31%) patients had relapse-free survival. For all 90 patients, the median overall survival was 20 months and the median relapse-free survival was 17 months. Overall and relapse-free survival was significantly longer for primary and persistent lesions as compared to recurrent and metastatic lesions (p = 0.002; p < 0.001). Totally 22 (24%) patients experienced acute or subacute side-effects (Grade 1: 12 patients; Grade 2: eight patients; Grade 3: two patients). CONCLUSION: Univariate logistic regression analysis revealed significant dependencies of CR, LC and REC upon tumor parameters as well as radiation and thermal parameters. The overall and relapse free survival was associated with tumor and radiation parameters. The multivariate analysis revealed two independent predictors of CR: tumor volume and minimum tumor temperature variables. We conclude, that IHT-IRT is a safe and effective treatment. The results provide important implications for planning HT-RT studies and for defining quality assurance (QA) criteria and thermal performance standards in HT studies.

Adolescent↗