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PubMedDate not supplied

Pancreatoduodenectomy for periampullary tumors: a univariate and multivariate analysis of the parameters influencing the morbidity, mortality, and survival rates.

A total of 69 patients who underwent a pancreatoduodenectomy (PD) for a periampullary tumor in the Department of Surgery I, Kyushu University Hospital from January 1980 to December 1993 were analyzed in order to identify the parameters influencing the morbidity, mortality and survival rates. Anastomotic leakage was seen in 15 of the 69 patients; at the site of a pancreatojejunostomy in nine and at the site of a biliojejunostomy in six. A univariate analysis of complications based on 16 factors showed that major intraabdominal complications (anastomosis leakage and intrabdominal hemorrhage and abscess) were significantly affected by blood loss (> or = 1600 g vs < 1600 g, p < 0.05). Two of the 69 patients died within one month after PD, and the mortality rate was 3%. A univariate analysis of the survival rates of the 69 patients based on the 16 parameters showed that a history of jaundice, the serum level of albumin, and the nature of disease (i.e. malignant or benign) significantly influenced the survival rates (p < 0.05). The year of operation, the age of the patients, the serum level of total bilirubin, the operation time and the operative blood loss were not significant variants. A multivariate Cox regression analysis on these three profound factors showed that malignant disease significantly influenced the clinical course of patients with PD (p < 0.01). With proper patient selection and operative techniques, PD can thus be safely performed for a wide variety of diseases, in virtually any age group.

Aged↗

PubMed2000

Complex adnexal masses: detection and characterization with MR imaging--multivariate analysis.

PURPOSE: To evaluate the accuracy of magnetic resonance (MR) imaging in the detection and characterization of complex adnexal masses, with particular reference to the findings predictive of malignancy, role of gadolinium-enhanced contrast material, and observer variability. MATERIALS AND METHODS: Preoperative MR imaging of the pelvis was performed in 128 consecutive patients with clinically or ultrasonographically detected complex adnexal masses. Histopathologic examination demonstrated 187 masses, 96 of which were malignant. MR imaging studies were prospectively and independently reviewed by two radiologists, one of whom reevaluated the studies after a 6-month interval. The predictive value of MR imaging findings was determined with multivariate logistic regression analysis. The value of gadolinium enhancement was assessed by using receiver operating characteristic analysis. Inter- and intraobserver variabilities were assessed by using weighted K statistics. RESULTS: Gadolinium-enhanced MR imaging depicted 176 (94%) of 187 adnexal masses, with an overall accuracy for the diagnosis of malignancy of 93%. The MR imaging findings that were most predictive of malignancy were necrosis in a solid lesion (odds ratio, 107) and vegetations in a cystic lesion (odds ratio, 40). Use of gadolinium-based contrast material contributed significantly to lesion characterization. Interobserver (K, 0.79-0.85) and intraobserver (K, 0.84-0.86) agreement were excellent. CONCLUSION: Gadolinium-enhanced MR imaging is highly accurate in the detection and characterization of complex adnexal masses, with excellent inter- and intraobserver agreement.

Adolescent↗

PubMed1984

Multivariate analysis of factors associated with invasive fungal disease during remission induction therapy for acute myelogenous leukemia.

The clinical courses of 54 consecutive adult patients with acute myelogenous leukemia (AML) who underwent 67 courses of intensive remission induction therapy were analyzed to assess factors associated with development of serious fungal and bacterial infections. Fever developed in 65 of 67 remission induction attempts and was due to bacterial, bacterial-fungal, and fungal etiologies in 49%, 14%, and 9% of cases, respectively. No etiology of fever was found in 28% of cases. Bacteremia occurred in 54% of remission induction attempts. Invasive fungal disease (IFD) occurred in 22% of cases with an overall mortality of 60%, including 45% of the patients who died during treatment. Using multivariate logistic regression analysis, a mathematical model was constructed which correlated with the risk of IFD. Major factors associated with patients who ultimately develop IFD included the duration of chemotherapy, the number of sites colonized with fungi and the number of fungal species isolated on certain surveillance cultures, particularly Aspergillus species. These studies define characteristics of patients at high risk for development of IFD for whom early initiation of empiric antifungal therapy is strongly recommended.

Adolescent↗

PubMed1991

Multivariate analysis of the risk of stomach cancer after ulcer surgery in an Amsterdam cohort of postgastrectomy patients.

Although gastric cancer incidence is decreasing in the western world, it remains an important cause of death, and there has been debate about screening persons who have undergone gastrectomy for benign ulcers. The authors analyzed risk factors for stomach cancer mortality in an Amsterdam cohort of 2,633 postgastrectomy patients, followed from their initial surgery between 1931 and 1960 until 1975, with 99.7% complete follow-up. Increased stomach cancer mortality was observed in the study population (compared with the general Dutch population) among males 25 years or more after surgery (observed/expected, 5.0; 95% confidence interval (Cl) 2.8-8.3), and among females 15-24 years postoperatively (observed/expected, 3.5; 95% Cl 1.0-9.0). A multivariate Poisson regression analysis showed that after control for age at time of surgery and calendar year of operation, the most important risk factors were time since surgery (0-4 years, relative risk (RR) = 1.0; 5-14 years, RR = 4.1, 95% Cl 0.93-18.5; 15-24 years, RR = 9.4, 95% Cl 2.1-42.3; and 25-46 years, RR = 55.6, 95% Cl 11.7-265.4) and ulcer location (gastric versus duodenal ulcer, RR = 2.6, 95% Cl 1.4-4.8). Surveillance for postgastrectomy cancer could be considered 15-25 years after a patient undergoes surgery for gastric ulcer disease.

Adult↗

PubMed1985

Sample attrition and multivariate analysis in the Retirement History Study.

The attrition of respondents in panel studies of older people can create bias in data analysis. Changes in the examination of attrition are suggested. Bivariate and multivariate tests comparing those eligible to respond and those actually continuing in the panel are reported for five waves of data from the Retirement History Study. The results indicate that variable relationships in the data examined are relatively free of the bias that can be created by respondent attrition. Thus, attrition from samples of older respondents probably is less of a factor than suggested by previous studies reporting on frequency distributions.

Aging↗

PubMed1981

Marijuana use and alienation: a multivariate analysis.

Research investigating the relationship between marijuana use and alienation is characterized by conflicting findings and a relative lack of multivariate designs. although a number of potential explanations for this lack of consensus are assessed, the primary focus of this study is on the type of analysis employed. Using bivariate analysis, significant positive associations were found between marijuana use and anomia, political alienation, and social isolation. However, when these same relationships were investigated in a multivariate design, controlling for other relevant factors, they failed to remain significant. These results indicate that there is no direct relationship between marijuana use and alienation. furthermore, the results question studies that have not taken into consideration relevant control variables in their analyses.

Adolescent↗

PubMed2005

CT findings as a significant predictive factor for the curability of mandibular osteomyelitis: multivariate analysis.

OBJECTIVES: To re-evaluate computed tomographic (CT) imaging as a diagnostic tool for mandibular osteomyelitis and to assess the clinical significance of CT findings. METHODS: CT images of 78 patients with mandibular osteomyelitis were reviewed. All patients were classified as cured or non-cured. Each CT finding was investigated for frequency, correlation with duration and disease cure. RESULTS: Of the 78 patients, 49 (63%) were classified as "cured" and 29 (37%) as "non-cured". Non-cured had experienced a significantly longer duration of symptoms. The most frequent CT finding was sclerosis and defect in the trabecular bone. Changes of bone width and thickening of the cortical plate were accompanied with longer disease duration. The extent of the diseased area was linearly correlated with the duration of symptoms. The significant factors to discriminate non-cured from cured were the extent of the disease, the number of findings, changes in the bone width, osteosclerosis and thickening of the cortex. Multivariate logistic regression analysis indicated that the extent of the disease and presence of changes in bone width were significant variables correlating with the cure of osteomyelitis. CONCLUSIONS: The extent of disease and the presence of change in bone width shown on CT were significantly correlated with the curability of osteomyelitis. These results indicated the usefulness and importance of CT examination for the diagnosis of mandibular osteomyelitis.

Adolescent↗

PubMed1995

[Multivariate analysis of clinico-pathologic predictors of axillary lymph node metastasis in invasive breast carcinoma].

UNLABELLED: The aim of this study was to find both predictors of axillary lymph node involvement and predictors of level II or III involvement. With these predictors patients should be selected who can be spared axillary lymph node dissection or who qualify for removal of only first-level lymph nodes. 239 consecutive patients with invasive breast cancer stage I-III treated with total axillary dissection were evaluated. In multiple logistic regression analysis 17 clinical and histopathological variables were included. We found 4 multivariate significant predictors for metastatic axillary involvement: Clinically positive axilla, peritumoural lymphatic vessel invasion, multicentric or multifocal tumours and a large number of past pregnancies. Multivariate significant predictors of involvement of level II or III were peritumoural lymphatic vessel invasion, younger age, larger tumour size, multicentric or multifocal tumours and postmenopausal patient. The metastatic involvement of more than 3 nodes was associated with young age and clinically positive axilla. With these easily available predictors a reliable assessment of risk of metastatic involvement of the upper levels of the axillary nodes could be defined. The binary logistic regression model to axillary node involvement had a rather unsatisfactory predictive value. CONCLUSIONS: The risk calculation of level II or III involvement with these predictors may help the surgeon to find the adequate extent of axillary clearance needed in the individual patient. Multiparity proved to be an independent predictor of metastatic axillary node involvement.

Adult↗

PubMed2001

Prediction of early bronchopleural fistula after pneumonectomy: a multivariate analysis.

BACKGROUND: The aim of this study was to determine independent risk factors for early bronchopleural fistula (BPF) after pneumonectomy and to assess the efficacy of bronchial coverage in preventing this complication. METHODS: We reviewed 242 consecutive patients undergoing pneumonectomy for lung cancer. The bronchial stump was covered with autologous tissue in 178 patients (74%). Perioperative data were recorded to identify risk factors of BPF by univariate and multivariate analyses. RESULTS: Overall morbidity and mortality rates were 59% and 5.4%, respectively. The incidence of BPF was 5.4%. By univariate analysis, patients with chronic obstructive pulmonary disease (COPD; p = 0.017), hyperglycemia (p = 0.003), hypoalbuminemia (p = 0.017), previous steroid therapy (p < 0.001), poor predicted postpneumonectomy forced expiratory volume in 1 second (FEV1; p = 0.012), long bronchial stumps (p < 0.001), and mechanical ventilation (p = 0.015), were related with higher risk of BPF. In the multiple logistic regression model, the independent risk factors of BPF were the bronchial stump coverage and length, side of pneumonectomy, predicted postpneumonectomy FEV1, COPD, and mechanical ventilation. CONCLUSIONS: Bronchial stump coverage is highly recommended in all cases to minimize the risks of BPF. A shorter length of the bronchial stump and early extubation may prevent the development of BPF. Careful attention must be paid to those patients with COPD and poor predicted postpneumonectomy FEV1.

Adult↗

PubMed1991

Identification of patients at high risk for colorectal carcinoma from biopsy studies of the apparently normal colorectal mucosa. A multivariate analysis.

A number of phenotypic abnormalities of the colorectal mucosa which appears normal have been described to be biomarkers of cancer development. To improve their sensitivity and specificity, we simultaneously determined 10 morphological and histochemical parameters in biopsies from the colonoscopically normal mucosa of the descending colon, sigmoid, and rectum. The results were analysed by multivariate statistical methods. We tested the discriminating power of proliferative, morphometric, enzyme and mucin histochemical parameters from 80 patients either at average risk (controls), with an increased risk for colorectal carcinoma (high-risk), or with a manifest carcinoma. The following parameters were investigated: number of mitotic figures per crypt, crypt length, apical, medial and basal crypt diameter, crypt surface, activity of succinate dehydrogenase (EC 1.3.99.1), activity of acid beta-galactosidase (EC 3.2.1.23), sulpho- and sialomucin contents. Univariate statistical analyses revealed that crypt length, crypt diameter and crypt surface were significantly increased in the high-risk group, the carcinoma carriers having intermediate values between average-risk and high-risk patients. In a two-group discriminant analysis, high-risk or carcinoma patients could be separated from average-risk patients with a sensitivity of 92.9% and a specificity of 100%. When the analysis was repeated for three groups (carcinoma carriers separated from high-risk patients), sensitivity and specificity were 100% for each group. We conclude that identification of patients at risk for colorectal carcinoma is possible from the normal-appearing left colonic and rectal mucosa by morphometric and cytochemical analysis of biopsies.

Aged↗

PubMed2004

Effect of training location and time period on racehorse performance in New Zealand. 2. Multivariable analysis.

AIM: To investigate training location (horses trained in Matamata vs those trained at all other venues in New Zealand), and time period (1996-1997 and 1998-1999), while controlling for other horse- and race- or trial-related factors, as a means of assessing the possible impact of construction of a new training surface at the Matamata Racing Club on indirect measures of racehorse performance (number of starts, and failure to race within 6 months of any start). METHODS: Multivariable logistic regression and poisson analysis were used to analyse data derived using a retrospective cohort approach. Multivariable logistic regression was also used to analyse a case-control study. All data were derived from New Zealand Thoroughbred Racing (NZTR), records of race and trial results for racehorses trained in Matamata and other venues in New Zealand, covering two 19-month time periods (1996- 1997 and 1998-1999). Outcome variables included whether a horse started again in the 6 months following any start that occurred in the first 13 months of either time period, and a count of the total starts for every horse. RESULTS: Factors associated with increased risk of a start being followed by a 6-month no-race period included training location other than Matamata in comparison to horses trained in Matamata in the 1996-1997 time period, increasing age, 1998- 1999 over 1996-1997, starting in a trial rather than a race, placing fourth or worse in a start, softer track conditions, summer vs autumn, increasing cumulative exercise intensity in the 60 days prior to a start, and increasing race distance. Factors associated with an increase in the total number of starts included horses trained at Matamata in 1996-1997 compared with other time period-location combinations, younger age of horses at the time of a start, longer race distance, and an increasing proportion of starts in stakes races. CONCLUSIONS: Official race and trial results data provided a valuable resource for epidemiological studies of factors influencing racehorse performance. Results of analyses performed here provided little evidence of any adverse impact of a new training surface at the Matamata Racing Club on indirect measures of racehorse performance.

Journal Article↗

PubMed1991

Identification of first acute Q wave and non-Q wave myocardial infarction by multivariate analysis of body surface potential maps.

BACKGROUND: Patients with acute non-Q wave myocardial infarction (NQMI) appear to have more jeopardized residual myocardium at high risk for subsequent angina, reinfarction, or malignant arrhythmias than patients with acute Q wave myocardial infarction (QMI). Unfortunately, conventional electrocardiographic (ECG) criteria have limited utility in recognizing NQMI. METHODS AND RESULTS: The present study combines the increased information content of body surface potential maps (BSPM) over the 12-lead ECG with the power of multivariate statistical procedures to identify a practical subset of leads that would allow improved diagnosis of NQMI. Discriminant analysis was performed on 120-lead data recorded simultaneously in 159 normal subjects and 308 patients with various types of myocardial infarction (MI) by using instantaneous voltages on time-normalized P, PR, QRS, and ST-T waveforms as well as the duration of these waveforms as features. Leads and features for optimal separation of 159 normals from 183 patients with recent or old QMI (group A) were selected. A total of six features from six torso sites accounted for a specificity of 96% and a sensitivity of 94%. All lead positions were outside the conventional electrode sites and selected features were voltages at mid-P, early and mid-QRS, and before and after the peak of the T wave. The discriminant function was then tested on 57 patients with acute NQMI (group B) and 68 patients with acute QMI (group C): Rates of correct classification were 91% and 93%, respectively. Because of the possible deterioration of the results caused by ST-T abnormalities also present in other clinical entities, a second classification model including an independent group of 116 patients with left ventricular hypertrophy (LVH) but without MI was developed. Two additional measurements were required, namely, P wave duration and a mid-QRS voltage on a lead located 10 cm below V1. Testing the model on both acute MI groups produced correct classification rates of 88% for acute NQMI and 93% for acute QMI. Group mean BSPM were plotted for the three MI groups at successive instants throughout the PQRST waveform. Typical patterns for each MI group were identified during PQRST by removing the corresponding normal variability at each electrode site from sequential MI maps. These standardized maps or discriminant maps provided information on the capability of each measurement at each electrode site and at each instant to separate each class of MI from the normal group (N). Striking similarities were observed between the three MI groups, particularly at mid-QRS and throughout ST-T. The closest resemblance was between acute NQMI and old QMI. Discriminant analysis was also performed on the 12-lead ECG: The first classification model (N versus MI) produced correct classification rates of 85% for acute QMI and 70% for NQMI. With the second model (MI versus N or LVH), correct rates were 81% and 65%, respectively. CONCLUSIONS: Diagnosis of acute NQMI and QMI (also in the presence of LVH) can be improved substantially by appropriate selection of ECG leads and features. Comparison of discriminant maps from groups A, B, and C does not support the concept of acute NQMI as a distinct ECG entity but rather as a group with infarcts of smaller size. However, pathophysiological and clinical differences between acute NQMI and acute QMI influence long-term risks and may define different therapeutic approaches.

Adult↗

PubMed1992

Multivariate analysis of the variables affecting left ventricular filling in normal subjects.

Pulsed Doppler measurements of left ventricular filling (LVF), two-dimensional and M-mode echocardiograms were performed in 189 healthy subjects, in order to evaluate factors influencing LVF Doppler indexes in normal subjects. LVF Doppler indexes (peak E, peak A, peak E/peak A, deceleration rate of peak E (ED) were related by univariate and multivariate analyses with the following parameters: age, sex, heart rate, systolic and diastolic blood pressure, aortic root and left atrial dimensions, left ventricular mass index, left ventricular shortening fraction. The stepwise analysis showed that age by itself explained up to 18% of peak E variance, 50% of peak A variance, 61% of peak E/peak A variance and 25% of ED variance. The other variables entered into the regression, slightly improved the predictive power (less than 10%). In conclusion, age is the major independent factor affecting LVF in normal subjects, although other variables show significant correlation also after age adjustment.

Age Factors↗

PubMed1993

[A multivariate analysis of the factors associated with the severity of chronic venous insufficiency].

Chronic Venous Insufficiency (CVI) affects a large proportion of individuals and, with the ageing of the population of Western Europe, its prevalence is expected to increase. Epidemiological data, particularly regarding risk factors, is scarce and controversial. The purpose of this study was to identify clinical factors that are associated with an increase in severity of CVI. Eighteen physicians observed 474 unselected patients with symptoms suggesting CVI. A multivariate model is forwarded in which age is a major risk factor. Other factors that are independently correlated with the severity of CVI are body weight, environmental heat, sedentariness, double heredity, high-dose oestrogen formulations, osteo-articular disease of the lower limbs, presence of troncular varices, involvement of the internal saphena, lymphedema or history of thrombophlebitis. Since most studies do not adjust for age when testing for risk factors, this may be an important reason for the multiplicity of reported factors and the lack of consistency of their results.

Adolescent↗

PubMed1991

The value of routine preoperative laboratory testing in predicting postoperative complications: a multivariate analysis.

The purpose of this study was to evaluate the ability of preoperative laboratory testing to predict postoperative complications. Five hundred twenty patients undergoing elective surgery had their American Society of Anesthesiologists' classification, ponderal index, electrolyte values, glucose levels, blood urea nitrogen/creatinine values, complete blood counts, coagulation studies, total protein/albumin/lymphocyte count, electrocardiogram, chest radiograph, urinalysis, pulmonary function tests, type of anesthesia, and type of operation recorded preoperatively. Patients were followed prospectively after surgery for the development of complications. The data were analyzed by univariate and multivariate methods. Postoperative complications were strongly associated with American Society of Anesthesiologists' classification, type of anesthesia, and type of operation. However, only a few laboratory tests, such as electrocardiogram, chest radiograph, and nutritional status, were associated with postoperative complications. Therefore, in general, preoperative laboratory testing should only be undertaken for specific indications. Recommendations for routine tests are made depending on the age of the patient.

Adult↗

PubMed1995

Asthma and bronchial reactivity: a contribution from multivariate analysis.

This study was performed on 508 young male candidates on the military pilot course of the Air Force Academy. Observations of the following parameters were made: immunoglobulin E (IgE) level, skin sensitivity test (prick test) to most common continuous and seasonal allergens, and results of nonspecific bronchial provocation tests with methacholine. The analysis strategy that has been developed consists of two techniques, "multiple correspondence analysis (MCA)" and "automatic classification". The correlation between the categories of the characters evaluated are: degree of high skin reactivity in relation to high IgE levels, hyperreactivity to low methacholine dose (noticed mainly in subjects allergic to continuous antigens), low degree of skin reactivity (both to continuous and seasonal antigens and found in relation to a low methacholine dose) and medium and low IgE levels. The cluster analysis defined three different classes of subjects: 1) 51.97% of the total observed subjects. 68.82% of those subjects that showed IgE levels above 7300 and a high reactivity to low methacholine dose; 2) 15.94% of subjects with a severe allergy to pollens; and 3) 32.09% of subjects with IgE levels lower than 900, low bronchial reactivity and no allergic component for either seasonal or continuous antigens. The use of multivariate statistical techniques in this field of pathophysiology has allowed a confirmative-explorative study of allergic phenomena in relation to several characters, and the determination of classes of subjects characterized by well-defined categories.

Adolescent↗

PubMed1994

Transarterial oily chemoembolization for the treatment of hepatocellular carcinoma: a multivariate analysis of prognostic factors.

A total of 84 patients with hepatocellular carcinoma and cirrhosis were analyzed retrospectively to investigate prognostic factors. All patients received transarterial oily chemoembolization as the only anticancer therapy. The follow-up range was 1 to 39 mo (median, 9.5 mo). The overall actuarial survival rates at 12, 24 and 30 mo were 62%, 31% and 24%, respectively. According to univariate analysis, variables significantly associated with survival were age, Child-Pugh grade, total serum bilirubin, Okuda stage, tumor size, degree of labeling of the tumor with Lipiodol, gelatin foam use, changes with treatment in tumor size and changes with treatment in alpha-fetoprotein concentration. Two multivariate analyses were performed. When pretreatment and treatment variables were considered, parameters with independent prognostic value were age, Child-Pugh grade, total serum bilirubin, tumor size and degree of Lipiodol labeling of the tumor. When follow-up variables were also considered, we (a) confirmed the prognostic significance of all these parameters (age, Child-Pugh grade, total serum bilirubin, tumor size) and (b) found the independent prognostic value of the change in tumor size (or change in alpha-fetoprotein concentration). Both models yielded different risk coefficients for each class of each variable. Two simple prognostic indexes, based on these coefficients, are proposed: an "initial" index (including pretreatment and treatment variables) and a "follow-up" index (also including follow-up variables). According to the two indexes, the patients were classified into three groups with different prognoses: good (93% and 100% actuarial survival at 1 yr for the initial and follow-up indexes, respectively), intermediate (65% and 53%, respectively) and poor (27% for both indexes).

Actuarial Analysis↗

PubMedDate not supplied

Pyogenic liver abscess: multivariate analysis of risk factors.

Seventy-three patients with pyogenic liver abscess during the year 1978-1988 were studied in the Kaohsiung Medical College Hospital. The overall mortality rate was 19.2% in this study. By using univariate analysis, it was revealed that clinical jaundice, pleural effusion, bilobar abscess, profound hypoalbuminemia (less than 2.5 g/dl), hyperbilirubinemia (less than 2 mg/dl), elevated level of serum AST (greater than 100 IU/L), alkaline phosphatase (greater than 150 IU/L), and marked leukocytosis (greater than 20,000 mm3) were associated with a higher mortality rate. Multivariate stepwise logistic regression analysis detected only 3 factors of marked leukocytosis (greater than 20,000 mm3), profound hypoalbuminemia (less than 2.5 g/dl), and presence of pleural effusion with independent significance in predicting mortality. Meanwhile, it was also revealed that the laboratory data could not predict a risk factor to mortality unless they became markedly abnormal.

Adult↗