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PubMed2004

Multivariate analysis on factors affecting suppression of thyroid-stimulating hormone in treated congenital hypothyroidism.

AIMS: To determine the factors which influence the suppression of thyroid-stimulating hormone (TSH) in infants with congenital hypothyroidism (CH) following treatment. METHODS: We examined retrospectively the patterns of thyroid function tests from diagnosis to 3 years of age in 140 infants diagnosed with CH from screening. Patients were classified into 3 groups: athyreosis, ectopia and presumed dyshormonogenesis on the basis of thyroid scans. Adequate TSH suppression was defined as plasma TSH concentration <6 mU/l. The factors affecting the suppression of TSH at 6 months and 1 year of age which were evaluated were: initial confirmatory plasma TSH, initial plasma thyroxine (T4), mean age of starting treatment with L-T4, dose of L-T4 at diagnosis, 6 weeks, 3 months and 6 months, and aetiology of the congenital hypothyroidism. Variables were then entered in a stepwise logistic regression model for TSH suppression at 6 months and 1 year of age. RESULTS: All infants had radionuclide scans prior to treatment: athyreosis (n = 39), ectopia (n = 78) and dyshormonogenesis (n = 23). 58% of patients had persistently raised TSH at 6 months of age while 31% of patients had a persistently raised TSH at 1 year of age. There was a significant delay in the normalisation of plasma TSH in athyreosis and ectopia groups compared with dyshormonogenesis. Multiple regression analysis for TSH suppression at 6 months of age found plasma T4 levels and aetiology of CH as independent factors affecting the timing of TSH suppression. Aetiology of CH was the only independent factor affecting TSH suppression at 1 year of age. CONCLUSION: At 6 months of age, plasma T4 levels at 6 weeks and 3 months, and aetiology of CH were independent factors affecting timing of TSH suppression. However, by 1 year of age, the aetiology of CH was the only independent factor affecting suppression of TSH.

Child, Preschool↗

PubMed1990

Linguistic and cognitive failures in schizophrenia. A multivariate analysis.

Schizophrenic (N = 38), manic (N = 30), and normal (N = 25) subjects were examined with laboratory tasks measuring serial recall and encoding, distractibility, and reality monitoring. In addition, the psychiatric patients were examined with three measures of verbal communication disorder, including positive thought disorder, negative thought disorder, and frequency of reference failures. It was found that positive thought disorder and reference failures in schizophrenics were best predicted by measures of distractibility and reality monitoring, with communication disorder in mania, although common and severe, not predicted by these cognitive performance measures. Furthermore, negative thought disorder in schizophrenics was not predicted by the cognitive measures. These results are discussed in terms of their implications regarding the differences in potential determinants of positive and negative thought disorders.

Adult↗

PubMedDate not supplied

Comparison of indocyanine green clearance with Child's-Pugh score and hepatic histology: a multivariate analysis.

BACKGROUND/AIMS: Indocyanine green clearance, measured by percentage disappearance rate, detects alterations in liver function and may be used as a non-invasive determinant of hepatic reserve. The aims of this study were to compare liver histology and Child's-Pugh score with percentage disappearance rate and determine which variables correlated with PDR. METHODOLOGY: Child's-Pugh score, liver function tests, liver biopsies and indocyanine green testing (0.5mg/kg) were performed in 102 consecutive patients with cirrhosis of diverse etiologies. Indocyanine green concentration was determined using spectrophotometric analysis (806nm) and plotted logarithmically with Michaelis-Menten kinetics to calculate the percentage disappearance rate. Liver biopsies were graded using the modified Knodell score to obtain a histological activity index. RESULTS: In bivariable analysis, percentage disappearance rate significantly correlated with Child's-Pugh score, albumin, bilirubin, prothrombin time and histological activity index. Albumin, prothrombin time and histological activity index were independent predictors of percentage disappearance rate in the final model (albumin p<0.01, prothrombin time p<0.046, histological activity index p=0.033), accounting for 46.2% of variability in percentage disappearance rate measurements. CONCLUSIONS: Percentage disappearance rates correlated with Child's-Pugh scores in this series of cirrhotic patients. However, 46.2% of its variability was accounted for by albumin, prothrombin time and histological activity index.

Coloring Agents↗

PubMed1993

Risk factors for groin node metastasis in squamous carcinoma of the vulva: a multivariate analysis of 39 cases.

This study includes 39 patients with squamous carcinoma of the vulva subjected to radical surgery. Stage, tumor description, cell type, lesion localization, lesion size, depth of invasion, grade, lymphovascular space invasion, number of mitoses, degree of stromal inflammatory reaction, and tumors in surgical margins were analyzed for groin metastasis. Of the factors analyzed, stage (P = 0.018), grade (P = 0.007) and depth of invasion (P = 0.001) were found to be the most important predictors of node metastasis. While a combination of factors permitted to define a low-risk group with 0% node metastasis, it seems hard to identify preoperatively those patients with no risk of nodal metastasis.

Adult↗

PubMed2003

Prognostic factors after resection for hepatocellular carcinoma in noncirrhotic livers: univariate and multivariate analysis.

The aim of this study was to investigate the prognostic factors for hepatocellular carcinoma (HCC) in patients without cirrhosis who underwent hepatectomy. Between 1986 and 1998 a total of 197 men and 57 women with noncirrhotic HCC underwent hepatic resection in the Department of Surgery, Chang Gung Memorial Hospital, Taipei, Taiwan. We determined their surgical mortality and the disease-free and overall cumulative survival rates. The surgical mortality was 4.7% and the 5-year disease-free survival rate 24.01%. By Cox regression analysis, serum alkaline phosphatase [relative risk (RR) 1.761; 95% confidence interval (CI) 1.037-2.985)], albumin (RR 2.179; CI 1.215-3.908), multiple tumor status (RR 2.288; CI 1.272-4.115), and blood urea nitrogen (RR 4.651; CI 1.116-19.38) were shown to be independent prognostic factors for the 5-year disease-free survival rates. The 5-year overall cumulative survival rate was 25.91%. By Cox regression analysis, serum albumin (RR 1.656, CI 1.005-2.730), blood transfusion (RR 2.075, CI 1.153-3.731), resection margin (RR 2.562, CI 1.436-4.572), and multiple tumors (RR 2.801, CI 1.727-4.545) were shown to be significant independent factors that influenced cumulative survival rates. Hence in patients with a noncirrhotic HCC who underwent hepatectomy the prognosis depended on preoperative hepatic function, the presence of multiple tumors, the need for blood transfusion, and the surgical resection margin.

Adult↗

PubMed1997

Behavioral reactivity to social and nonsocial stimulations: a multivariate analysis of six inbred rat strains.

Male rats from six inbred rat strains (Spontaneously Hypertensive Rat, Wistar Kyoto, Brown Norway, Wistar Furth, Fischer 344, and Lewis) have been compared for their behavioral reactivity when placed in several nonsocial (elevated plus-maze, open field) and social (social interaction in aversive and neutral environment, resident-intruder test, chronic social stress) settings. In addition, a factorial analysis was performed to assess how the variables measured in these different tests related to each other. Besides significant strain-related differences in all tests, the factorial analysis showed that, in nonsocial environments, the strains contrasted essentially along two independent behavioral traits, the propensity to approach or avoid an aversive stimulus and general motor activity in novel environments (two indices of emotionality). In the social settings, marked interstrain differences were observed regarding the expression of aggressive behaviors but these differences were not related to the respective levels on the two nonsocial components of reactivity. Furthermore, large genetic differences were observed in variations of body weight induced by a chronic social stressor paradigm. The factorial analysis suggested a lack of relationship between the effect of social stressors on body weight and the measures of emotionality and general activity obtained in the nonsocial tests. Conversely, these variations were influenced by the levels of aggressiveness and sociability. Taken together, these results show (i) that the behavioral variability observed in rats in social and nonsocial environments, is influenced by genetic factors and (ii) that the behavioral reactivity to social stimulations is a specific feature, dissociable from the levels of the different components of emotionality (approach/avoidance and general activity) as evaluated by the behavioral responses to nonsocial settings.

Aggression↗

PubMed2000

[Risk adjustment in external quality assurance with multivariate analysis].

Surgical clinics throughout Germany are under political and economical pressure. Comparing outcomes across clinics or ranking become more and more popular although there are no generally accepted and scientifically valid methods how to compare. Using original data of the external quality assurance project of the chamber of physicians of Westfalia-Lippia it is shown in this article that comparing raw data is often misleading. Differences in risk factors (case mix) have to be taken into consideration. A model using logistic regression methods to adjust for case mix in legality and morbidity of hip fractures is proposed. A ranking list before and after adjusting for risk factors shows partly dramatic changes. One clinic for example changed from position 97 (out of one hundred) to position 26.

Aged↗

PubMed2003

Prognostic factors in acute respiratory distress syndrome: a retrospective multivariate analysis including prone positioning in management strategy.

OBJECTIVE: To investigate the prognostic factors in acute respiratory distress syndrome (ARDS) patients focusing on the use of prone positioning (PP). DESIGN AND SETTING: Retrospective study conducted in an intensive care unit of a university hospital. PATIENTS: All consecutive mechanically ventilated ARDS patients surviving on day 7 after the diagnosis of ARDS. METHODS: The study included all ARDS patients who survived more than 7 days after ARDS diagnosis between January 1995 and December 2002. Demographic and respiratory variables were collected on day 1, and the management of ARDS was analyzed during the first 7 days ( n=125). We performed a univariate analysis and a stepwise logistic regression analysis comparing survivors and nonsurvivors on day 28 and at 2 and 6 months. RESULTS: Mortality rates on day 28 and at 2 and 6 months were 21.6%, 32%, and 44% respectively. A SAPS II score less than 49, McCabe score, and the use of PP introduced in the first 7 days of ARDS management appeared to be independently correlated with a decrease in mortality. CONCLUSIONS: The SAPS II score, the McCabe score, and use of PP are independently correlated with the outcome in ARDS patients.

Critical Care↗

PubMed2000

Multivariate analysis of male mating success on morphometric traits and chromosome dosage in the grasshopper Sinipta dalmani.

Sinipta dalmani is a South American grasshopper that is chromosomally polymorphic for a pericentric inversion in the M4 pair. The inversion affects morphology, showing a negative average effect on body size. In the present work, male mating success was analysed in competition cages and possible correlations examined between this fitness component, body size and inversion polymorphism. The outcome of the study revealed that mated males were larger and had lower inversion dosage than unmated ones. The analysis of standardized selection differentials (S') demonstrated that directional selection operated on chromosome dosage and 3rd tibia, 3rd femur, thorax and tegmina lengths. The analysis of karyotype frequencies showed that mated males had a higher frequency of the standard homozygote karyotype. The analysis of selection gradient (beta') and the transformed logistic regression (alpha) showed an important effect of selection on 3rd tibia length. Identical conclusions were obtained when linear and logistic multiple regression were performed on the first three components of PCA analyses. Our results indicate that differences in some body size-related traits are determined by the karyotype, and that of these length of 3rd tibia provides the greatest contribution to variation in fitness. The selective effects detected on chromosome dosage and the other morphological traits may be considered as indirect ones caused by correlated effects.

Animals↗

PubMed1994

[Multivariate analysis of risk factors of rejection in penetrating keratoplasty].

In order to evaluate preoperative risk factors that affect the incidence of endothelial rejection after penetrating keratoplasty, we performed statistical analysis on 571 consecutive cases who had been followed at the University of Tokyo Hospital for at least one year. We applied a logistic regression model (multiple variate analysis) to determine the significance of the association between the preoperative factors and the incidence of rejection. We identified four preoperative risk factors of endothelial rejection in a year as follows: the extent of corneal vascularization, failed previous graft continuous sutures, and preoperative corneal endothelial damage. When the rejection cases were divided into an early group that suffered rejection within 3 months and a late group that suffered rejection after 6 to 12 months, young patients were likely to suffer rejection in the early postoperative period.

Adolescent↗

PubMedDate not supplied

[Factors associated with low birth weight: a multivariate analysis].

The low birth weight of infants is a major public health problem of unknown cause in Benin. We recruited 4,213 pregnant women from a maternity ward in Cotonou for a prospective study. The women were interviewed and further information was obtained from their maternity records. The women were followed until delivery. We found that 6.9% of the births occurred pre-term and there was intrauterine growth retardation in 10.9% of cases. Multiple regression analysis showed that the risks of giving birth to underweight infants were highest for women who were themselves underweight, who had complications due to bleeding or malaria or had social and psychological risk factors. For these particular women, unwanted pregnancy (ORa = 1.60; CI = 1.30-2.00) and lifting heavy loads (ORa = 1.30; CI = 1.10-1.60) were high risk factors. However, adequate prenatal care (ORa = 0.85; CI = 0.69-0.99) and having given birth before were protective factors, reducing the likelihood of a low birth weight. These results have implications for preventive care, in terms of nutrition during pregnancy and psychosociological factors.

Adult↗

PubMed1985

Genetic variants of human erythrocyte glucose-6-phosphate dehydrogenase: new characterization data obtained by multivariate analysis.

Thirteen variables used in the course of characterization of G6PD variants from forty-one individuals have been submitted to multivariate factorial and cluster analysis. Because of the diagrammatic representation of the analysis, two main findings were made possible. Firstly, the three-dimensional plot of the experimental data gives the advantage of a model of classification which is closely related to the ethnogeographical origin of the subjects, and to the clinical and haematological incidence of the G6PD variants. Secondly, cluster analysis visualizes the distance between the G6PDs examined. In this respect, it was determined that three local original variants associated with acute haemolytic anaemia showed a close relationship and belonged to the same cluster (Gd(-) Toulouse, Gd(-) Muret and Gd(-) Colomiers). Conversely, two non-haemolytic variants (G6PD Luz Saint Sauveur and Lozère) were found to be linked in another remote cluster. The procedure developed in this work promotes a new approach to G6PD characteristics in human genetic studies.

Adolescent↗

PubMed2000

Discrimination between malignant and nonmalignant ascites using serum and ascitic fluid proteins in a multivariate analysis model.

Our objectives were to study the value of different proteins in the serum and ascitic fluid and assess their potential in discriminating between malignant and nonmalignant ascites in a model that could be developed to aid clinical diagnosis. In all, 57 different measurements (30 in serum and 27 in ascitic fluid) including erythrocyte sedimentation rate, number of white blood cells, cytokines, interleukin-1a (IL-1a), IL-1b, IL-2, IL-6, IL-8, tumor necrosis factor-alpha, immunoglobulins (IgG, IgA, IgM), complement factors C3 and C4, acute-phase proteins such as alpha1-acid glycoprotein, alpha2-macroglobulin, alpha1-antitrypsin, haptoglobin, C-reactive protein, ferritin, ceruloplasmin and transferin, were performed in 61 patients with ascites (25 with malignant exudates, 13 with nonmalignant exudates, and 23 with transudates). Patients with sepsis were excluded. Correlation tests and one-way ANOVAs were used for comparisons between different groups. Discriminant analyses were used to assess the significance of each parameter in the differentiation process. Correct classification of 100% of cases required the use of all 57 ascitic fluid measurements in the model, which was not considered practical in clinical diagnosis. Discriminant analysis showed that five ascitic fluid measurements-total protein, LDH, TNF-alpha, C4, and haptoglobin-were sufficient for a model to correctly classify 89% of cases. Cross-validation showed that 70% of unknown cases were correctly classified using this model. In conclusion, we have shown that five easily taken protein measurements in the ascitic fluid can differentiate to a large extent between cases with ascites and have proposed a relatively simple statistical model with these parameters that could be developed to be extremely useful in the clinical setting.

Adult↗

PubMed2000

Severity of acute pancreatitis: a multivariate analysis of oxidative stress markers and modified Glasgow criteria.

BACKGROUND: It is unknown whether measurement of markers of oxidative stress can improve the prediction of severity of acute pancreatitis. METHODS: Consecutive patients admitted with a diagnosis of acute pancreatitis were divided into mild (n = 62) and severe (n = 23) groups based on the Atlanta classification. Plasma oxidative stress markers were measured within 24 h of admission and included ascorbic acid (endogenous antioxidant), protein carbonyl (a marker of protein oxidation), thiobarbituric acid reactive substances (a marker of lipid peroxidation) and myeloperoxidase (a neutrophil enzyme that produces oxidants). Canonical correlation analysis was used to describe the relationship between these markers and the modified Glasgow criteria. Canonical variate analysis was used to define the best variables that could discriminate mild and severe pancreatitis. RESULTS: There was a significant correlation between markers of oxidative stress and the modified Glasgow criteria (first canonical correlation 0.69, P < 0.0001, Wilk's lambda test). Blood urea, serum albumin and white cell count were the best variables that discriminated mild and severe acute pancreatitis, and all were better than the oxidative stress markers. CONCLUSION: The markers of oxidative stress were highly correlated with the severity of pancreatitis. They are unlikely to be better than the modified Glasgow criteria in predicting it.

Acute Disease↗

PubMed2002

Hydrate formation during wet granulation studied by spectroscopic methods and multivariate analysis.

PURPOSE: The aim was to follow hydrate formation of two structurally related drugs, theophylline and caffeine, during wet granulation using fast and nondestructive spectroscopic methods. METHODS: Anhydrous theophylline and caffeine were granulated with purified water. Charge-coupled device (CCD) Raman spectroscopy was compared with near-infrared spectroscopy (NIR) in following hydrate formation of drugs during wet granulation (off-line). To perform an at-line process analysis, the effect of water addition was monitored by NIR spectroscopy and principal components analysis (PCA). The changes in the crystal arrangements were verified by using X-ray powder diffraction (XRPD). RESULTS: Hydrate formation of theophylline and caffeine could be followed by CCD Raman spectroscopy. The NIR and Raman spectroscopic results were consistent with each other. NIR revealed the state of water, and Raman spectroscopy gave information related to the drug molecule itself. The XRPD confirmed the spectroscopic results. PCA with three principal components explained 99.9 of the spectral variation in the second derivative NIR spectra. CONCLUSIONS: Both CCD Raman and NIR spectroscopic methods can be applied to monitoring of hydrate formation processes. However, NIR is more suitable for monitoring solid-water interactions.

Multivariate Analysis↗

PubMed1991

Death and functional outcome after spontaneous intracerebral hemorrhage. A prospective study of 166 cases using multivariate analysis.

Using death and functional status as end points, we prospectively analyzed the outcome 6 months after spontaneous intracerebral hemorrhage in 166 patients admitted to an acute-care stroke unit on the first day of their stroke. Seventy-one patients (43%) died, 69 (42%) had a satisfactory outcome, and 26 (16%) had a poor functional outcome. Early (30-day) survival was correlated with morphologic parameters on the initial computed tomogram (hemorrhage size, midline shift, and intraventricular spread of the hemorrhage), while later (6-month) survival was correlated with age. Using logistic regression, we found five independent predictors of satisfactory outcome at 6 months: age, hemorrhage size, intraventricular spread of the hemorrhage, limb paresis, and communication disorders. Of these, age was the most important predictor by far.

Adult↗

PubMed1997

Factors affecting survival after excision of the rectum for cancer: a multivariate analysis.

PURPOSE: The aim of this study was to identify and categorize the independent prognostic effects of patient, clinical, operative, and pathology variables on long-term survival after anterior resection or abdominoperineal excision of the rectum for cancer. METHODS: Proportional hazards regression analysis was used to analyze prospective data from 709 patients who underwent surgery at Concord Hospital during a 23-year period. No patient received adjuvant therapy. RESULTS AND CONCLUSIONS: After adjusting for age and clinicopathologic stage, significantly poorer survival was experienced by males, patients with extensive tumor adherent to other organ(s), those with a high-grade tumor or a tumor showing venous invasion, those who had a postoperative cardiovascular or respiratory complication, and those who did not undergo surgery by a colorectal surgeon specialist. The nature of the operation performed had no independent effect on survival.

Anastomosis, Surgical↗

PubMed2005

Multivariate analysis of predictors of late stroke after total aortic arch repair.

OBJECTIVE: The number of aortic surgeries has recently increased, with improvement of outcome due to the development of various novel operative techniques and adjuncts. Although the postoperative incidence of stroke, the most severe complication of aortic surgery, is still a matter of concern and has been described well previously, late stroke after aortic arch repair has not been described well. We assessed the incidence and predictors of late stroke after total aortic arch repair. METHODS: From January 1993 to December 2003, 470 patients underwent total aortic arch repair in our institution. All patients, whether undergoing elective, urgent, or emergent aortic arch repair, were included. Emergent operation was required for 115 patients because of rupture or acute type A dissection. For brain protection, retrograde cerebral perfusion was used in 27% (125) and selective cerebral perfusion in 75% (353) of cases. The follow-up period was 32.5+/-31.5 months. Late stroke was defined as stroke occurring more than 30 days postoperatively. RESULTS: The incidence of early postoperative stroke was 4.9% (23/470), while that of late postoperative stroke was 6.0% (28/470). On univariate analysis, postoperative atrial fibrillation (P=0.014), preoperative prevalence of craniocervical lesions (P=0.0001), and advanced age (P=0.046) were each significantly related to late stroke. A Cox proportional hazards model detected postoperative atrial fibrillation (P=0.013, OR=3.02, 95% CI: 1.26-7.24) and preoperative prevalence of craniocervical lesions (P=0.0001, OR=5.37, 95% CI: 2.30-12.52) as predictors of late stroke. CONCLUSIONS: Postoperative atrial fibrillation and preoperative prevalence of craniocervical lesions were found to be risk factors for late stroke after total aortic arch repair.

Acute Disease↗