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PubMed2003

Risk factors for postoperative infectious complications in noncolorectal abdominal surgery: a multivariate analysis based on a prospective multicenter study of 4718 patients.

HYPOTHESIS: Infectious complications are the main causes of postoperative morbidity in abdominal surgery. Identification of risk factors, which could be avoided in the perioperative period, may reduce the rate of postoperative infectious complications. DESIGN: A database was established from 3 prospective, randomized, multicenter studies. Multivariate analysis was performed using nonconditional logistic regression expressed as an odds ratio (OR). SETTING: Multicenter studies (ie, private medical centers, institutional hospitals, and university hospitals). PATIENTS: From June 1982 to September 1996, a database was established containing the information of 4718 patients who underwent noncolorectal abdominal surgery. MAIN OUTCOME MEASURES: The dependent variables studied included surgical site infection (SSI) (divided into parietal and deep infectious complications with or without fistulas) and global infectious complications (SSI and extraparietal and abdominal infectious complications). RESULTS: The rate of global infectious complications was 13.3%; SSI, 4.05%; parietal infectious complications, 2.2%; deep infectious complications with fistulas, 2.18%; and deep infectious complications without fistulas, 1.38%. In multivariate analysis, the following 7 independent risk factors for global infectious complications have been identified: age (60-74 years, OR, 1.64; >or=75 years, OR, 1.45); being underweight (OR, 1.51); having cirrhosis (OR, 2.45), having a vertical abdominal incision (OR, 1.66); having a suture placed or an anastomis of the bowel (OR, 1.48) in the digestive tract; having a prolonged operative time (61-120 minutes, OR, 1.66; 121 minutes, OR, 2.72); and being categorized as having a class 4 surgical site (ie, obese patients or having a risk factor of a healing defect) (OR, 1.66). Ceftriaxone sodium therapy was identified as a protective factor (OR, 0.43). In multivariate analysis, the following 5 independent risk factors for SSI have been identified: the existence of a preoperative cutaneous abscess or cutaneous necrosis (OR, 4.75), having a suture placed or an anastomosis of the bowel (OR, 1.82) in the digestive tract, having postoperative abdominal drainage (OR, 2.15), undergoing a surgical procedure for the treatment of cancer (OR, 1.74), and receiving curative anticoagulant therapy (OR, 3.33) postoperatively. CONCLUSIONS: Our data show that risk factors for SSI and for global infectious complications are disparate. Indeed, only the placement of a suture or having an anastomosis of the bowel in the digestive tract is a risk factor for both SSI and global infections. Some of these factors may be modifiable before or during the surgical procedure to reduce the infection rate or to prevent postoperative complications.

Adult↗

PubMed2001

Multivariate analysis of regional metabolic differences in normal ageing on localised quantitative proton MR spectroscopy.

We performed multivariate analysis of regional differences and normal age-related changes in metabolites in the lentiform nucleus and frontal lobe, as measured by proton MRS. The cerebrospinal fluid (CSF) in the measurement area was estimated and the metabolite concentration adjusted. The concentration of N-acetylaspartate (NAA) in the lentiform nucleus decreased with ageing (F = 4.11, P < 0.01), but that in the frontal lobe did not change (F = 0.93, P = 0.45). This is in marked contrast with pathological dementia, such as Alzheimer's disease. In this multivariate analysis, the normal change in metabolism with ageing differed depending on the cerebral region, suggesting that metabolite concentrations, especially that of NAA may be useful metabolic indices for discriminate normal ageing from pathological dementia.

Adult↗

PubMed2004

[Clinical characteristics and multivariate analysis of prognostic factors in recurrent laryngeal carcinoma].

BACKGROUND & OBJECTIVE: The recurrence is an important factor affecting the prognosis of laryngeal carcinoma. There are few reports on the clinical characteristics and the prognostic factors of recurrent laryngeal carcinoma. The purpose of this study was to analyze the clinical features and prognostic factors of recurrent laryngeal carcinoma. METHODS: The data of 80 patients with recurrent laryngeal carcinoma between 1990 and 1997 were retrospectively investigated. Survival analysis was performed by Kaplan-Meier method; comparison among/between groups was performed using log-rank test; multivariate analysis was carried out using Cox proportional hazard model. RESULTS: The recurrence sites included locoregional recurrence, neck lymph node and distant metastases. The 3-year and 5-year overall survival rates for patients with recurrent laryngeal carcinoma were 50.6% and 34.6%, respectively. The 5-year disease-specific survival rates for the patients treated with surgery, surgery + radiotherapy, and surgery +chemotherapy (30 cases) was 73%. The recurrence of laryngeal carcinoma were developed within 1-156 months, the median time of recurrence was 11 months; there were 36 locoregional recurrence, 36 neck lymph node recurrence, 4 locoregional recurrence associated with neck lymph node recurrence, 1 locoregional recurrence associated with distant metastases, 3 neck lymph node recurrence associated with distant metastases. Univariate analysis revealed that the factors impacting the prognosis were recurrent site, duration of recurrence gaps, treatment modality of recurrence, and age (P< 0.05). The neck lymph node recurrence group, peristomal recurrence group, distant metastases group, radiotherapy and chemotherapy after recurrence group had a poorer prognosis than locoregional recurrence group, larynx recurrence group, without distant metastases group, and surgery group (P< 0.05). Multivariate analysis showed that age > or =60 years old, duration of recurrence gap < 12 months, distant metastases and radiotherapy or chemotherapy modality after recurrence were independently associated with decreased survival rates (P< 0.05). CONCLUSION: Surgery or surgery dominated multi-modality therapy was the principal treatment modality for recurrence laryngeal carcinoma. Age > or =60 years old, duration of recurrence gap < 12 months, distant metastases and salvage therapy by radiotherapy and chemotherapy but not surgery were independent factors affecting the prognosis.

Adult↗

PubMed1994

A multivariate analysis of repeated measures: linkage of the albinism gene (Tyr) to a QTL influencing ethanol-induced anesthesia in laboratory mice.

We propose the use of multivariate analysis of variance in order to address linkage relationships between a genetic marker and a phenotype that is specified by multiple variables. Moreover, enhanced power of a linkage model that simultaneously accounts for environmental factors is demonstrated in the present study. This strategy was used to establish linkage of a quantitative trait locus influencing ethanol-induced anesthesia to the albinism gene (Tyr) in mouse. This approach, which can be implemented immediately with most statistical packages, provides the extreme flexibility of multivariate analysis of variance for analyzing complex questions of linkage regarding either animal or human research paradigms.

Albinism↗

PubMed1996

Risk factors for central nervous system involvement in non-Hodgkins-lymphoma--a multivariate analysis.

A consecutive cohort of patients with NHL was examined to identify the factors predictive of CNS-involvement with Cox's proportional hazards model in a multivariate analysis. Twenty-seven cases of CNS-involvement were found among 498 patients with NHL. Only 3 of 96 patients with low-grade lymphomas had CNS involvement, all occurring after transformation into high-grade lymphoma. In univariate analysis of 402 patients with intermediate or high-grade lymphoma, lymphoblastic histology (including Burkitt's lymphoma), age <35 years, B-symptoms, stage IV disease, testis involvement and bone marrow involvement were found to be statistically significant risk factors. Lymphoblastic histology was found to be strongly correlated to age younger than 35 years. In the multivariate analysis only lymphoblastic histology, stage IV disease and B-symptoms were found to be significantly associated with CNS involvement. It is concluded that CNS prophylaxis should be considered in all patients with lymphoblastic histology and in patients with stage IV B lymphomas other than those of low-grade types.

Actuarial Analysis↗

PubMed2006

Prognostic factors in neocortical epilepsy surgery: multivariate analysis.

PURPOSE: Defining prognostic factors for neocortical epilepsy surgery is important for the identification of ideal candidates and for predicting the prognosis of individual patients. We use multivariate analysis to identify favorable prognostic factors for neocortical epilepsy surgery. METHODS: One hundred ninety-three neocortical epilepsy patients, including 91 without focal lesions on MRI, were included. Sixty-one had frontal lobe epilepsy (FLE), 80 had neocortical temporal lobe epilepsy (nTLE), 21 had parietal lobe epilepsy (PLE), and 22 had occipital lobe epilepsy (OLE). The primary outcome variable was patient status >or=2 years after surgery (i.e., seizure free or not). Clinical characteristics and the recent presurgical diagnostic modalities were considered as probable prognostic factors. Univariate and standard multiple logistic regression analyses were used to identify favorable prognostic factors. RESULTS: The seizure-free rate was 57.5%. By univariate analysis, a focal lesion on MRI, localized ictal onset on surface EEG, epilepsies other than FLE, localized hypometabolism on fluorodeoxyglucose-positron emission tomography (FDG-PET), and pathologies other than cortical dysplasia were significantly associated with a seizure-free outcome (p<0.05). Multivariate analysis revealed that a focal lesion on MRI (p=0.003), correct localization by FDG-PET (p=0.007), and localized ictal onset on EEG (p=0.01) were independent predictors of a good outcome. CONCLUSIONS: The presence of a focal lesion on MRI, correct localized hypometabolism on FDG-PET, or localized ictal rhythms on EEG were identified as predictors of a seizure-free outcome. Our results suggest that these findings allow the selection of better candidates for neocortical epilepsy surgery.

Adult↗

PubMedDate not supplied

Differential diagnosis of Krukenberg tumors using multivariate analysis.

AIMS AND BACKGROUND: Krukenberg tumors are ovarian metastases from a gastroenteric malignancy in 90% of cases. At present, diagnostic imaging techniques (US, CT, MRI) do not provide any reliable diagnostic criteria to differentiate these metastases from ovarian primaries. We tried to use multivariate analysis to distinguish malignant ovarian primaries from Krukenberg tumors based on their differential natural history. PATIENTS AND METHODS: We retrospectively compared the CT findings of Krukenberg tumors (47 patients, 79 masses, only from gastroenteric malignancy) with CT findings of primary epithelial ovarian cancers (46 patients, 67 masses). We compared the same independent variables in the two groups: age, morphology, margins, carcinomatosis, bilateral versus unilateral involvement, ascites, lymph node involvement, metastases on the basis of multivariate analysis. RESULTS: According to the best fitted model, clear-cut margins (OR: 3.75; 95% CI: 1.14-9.72) and the presence of carcinomatosis (OR: 4.21; 95% CI: 1.51-11.72) were the strongest predictors of a diagnosis of Krukenberg tumor. In contrast, the presence of ascites was more likely to be a protective factor (OR: 0.22; 95% CI: 0.08-0.62). CONCLUSIONS: We can try to make a differential diagnosis between a metastatic lesion from the gastroenteric tract and a primary adnexal lesion based on the multivariate statistical analysis of intraperitoneal spread of the different types of cancer rather than on morphologic findings at CT.

Adolescent↗

PubMed1989

Prognostic value of histologic grade nuclear components of Scarff-Bloom-Richardson (SBR). An improved score modification based on a multivariate analysis of 1262 invasive ductal breast carcinomas.

We did a multivariate analysis of 1262 patients with operable, invasive ductal breast carcinoma to assess the prognostic value of the Scarff-Bloom-Richardson (SBR) histologic grading system. Nodal metastasis and SBR were the two most important factors for metastasis-free survival (MFS), P = 10-9 and P = 10-5, respectively, for total study time. In patients who were node negative, the SBR and International Union Against Cancer (UICC) stages were the most important for MFS (P = 4 X 10-4 and P = 0.03). In order to try to improve the SBR prognostic value, we first studied the three components of the SBR separately: ductoglandular differentiation proved the least predictive and nuclear pleomorphism and mitotic index the most predictive. A rearrangement of the two nuclear scores alone produced higher risk values and better risk separation of patient subpopulations than SBR, and eliminated the SBR from the multivariate model. This rearrangement, modified SBR (MSBR), defined five new risk subgroups with statistically different risk ratios for MFS (P = 3 X 10-8). SBR grade II (55% of patients) was separated into three MSBR groups significantly different according to MFS (P = 0.008). In the patients who were node negative, MSBR replaced the SBR and was the most important factor for prediction of relapse of MFS (P less than 0.00001). The MSBR is more accurate and predictive than the standard SBR grade and is particularly useful when the nodal status of the patient is negative or unknown.

Adult↗

PubMedDate not supplied

[Multivariate analysis of aminoacyl-tRNA synthetase activities of liver and hepatomas (author's transl)].

Data on the aminoacyl-tRNA synthetase activities in normal liver and in three transplantable rat hepatomas, viz Yoshida's AH 130 and Morris's 5123C and 7793, were studied by means of factor analysis, a powerful technique of multivariate analysis particularly suitable foridentifying factors which theoretically may account for the pattern of interrelations between several variables. The analysis has been performed on 51 patterns of enzyme activities, covering 17 out of the 20 aminoacyl-tRNA synthetases; 80% on average of the total variability of the 17 enzyme activities may be accounted for by the first 4 factors extracted. The enzymes seem to fall into different groups, depending on their relationship with the factors thus identified. The results suggest that enzymes belonging to the same group share a common control mechanism, and are independent of the enzymes belonging to different groups, both in normal liver and in hepatomas.

Amino Acyl-tRNA Synthetases↗

PubMed1995

[Multivariate analysis of spinal automatism in neurological diseases].

We investigated the relationship between spinal automatism (SA) and other neurological signs and symptoms (pyramidal, extrapyramidal, cerebellar, autonomic) by multivariate analysis in cervical spondylotic myelopathy (CSM) 112 cases, amyotrophic lateral sclerosis (ALS) 121 cases, and multiple system atrophy (MSA) 115 cases (olivo-ponto-cerebellar atrophy (OPCA) 55 cases, Shy-Drager syndrome (SDS) 42 cases, striato-nigral degeneration (SND) 18 cases). SA elicitation maneuver we used was pinprick stimulation at the dorsal pedal skin, and all cases showed twitched or phasic triple flexion pattern. As SA was elicited in 19 cases in CSM (17.0%), 23 cases (19.0%) in ALS, 36 cases (31.3%) in MSA, SA was more elicited in MSA than in ALS and CSM (p < 0.05, p < 0.01 by chi-squared test). In MSA, SA tended to be elicited more likely in SDS (21 cases, 50.0%) and in SND (8 cases, 44.4%) than in OPCA (7 cases, 12.7%) (p < 0.01 by chi-squared test). In MSA, the longer the duration of the disease became, the more SA was elicited, but not in ALS and CSM. Multivariate analysis (quantification method type II) showed that clinical signs as a statistical contribution factor for SA elicitation ranked Babinski's sign, micturition disturbance in ALS and CSM and Babinski's sign, orthostatic hypotension in MSA in order: In all 3 diseases, Babinski's sign and autonomic disturbance ranked higher. This conclusion suggested that SA was not always related to the pyramidal tract damage and was associated with the damage of small myelinated fibers in and/or around the pyramidal tract.

Adult↗

PubMed1995

A multivariate analysis of childhood abdominal pain in Trinidad.

This is a multivariate analysis of the data recorded in assessing 1158 consecutive admissions presenting to a children's surgical ward with acute abdominal pain. There were 56 binary variables available for entry into the analysis. A statistical software package was used to perform a stepwise discriminant analysis on the data. The program selected 18 variables as having discriminating power in assigning patients to the six diagnostic groups. In order of discriminating power these were, mainly, a positive urine culture, the bowel history, the findings on rectal examination, the location of abdominal tenderness, the presence of a mass, and the white cell count. Lesser discriminating potential was assigned to the presence of dehydration; fluid levels on erect abdominal films, a rise in temperature, an increased pulse rate, the presence of urinary symptoms, and the general appearance of the child. Use of these data led to an overall correct classification of 80.7% of cases. It is concluded that these variables should be included in the assessment of children with acute abdominal pain.

Abdomen, Acute↗

PubMed1988

Multivariate analysis for histologic prognostic factors in soft tissue sarcomas.

To investigate histologic prognostic factors in soft tissue sarcomas (STS), multivariate analysis was performed on 236 patients with complete clinical information. These included 141 males and 95 females with an age range from 1 to 85 years (median, 47.6 years). Histologically, malignant fibrous histiocytoma (33.5%) was the most common type followed by synovial sarcoma (11%), liposarcoma (10%), rhabdomyosarcoma (7%), and leiomyosarcoma (7%). Monofactorial analysis revealed that sex, depth, location, histologic grade, cellularity, frequency of mitosis, and necrosis were significant prognostic factors. By multivariate analysis, only frequency of mitosis and depth of tumors were proved to be of prognostic significance. The prognostic importance of the frequency of mitosis as shown in previous and the present studies indicates that further investigation of the cell proliferation in patients with STS is required.

Age Factors↗

PubMed1990

Prognostic risk factors for graft failure following pancreas transplantation: results of multivariate analysis of data from the International Pancreas Transplant Registry.

A multivariate analysis of prognostic factors for graft failure was performed on patients in the International Pancreas Transplant Registry. The analysis was restricted to the period January 1978 to June 1987 and included 764 patients. All patients had at least 1 year of follow-up. The following variables were studied: transplant year, continent (N. America, Europe, others), type of donor (cadaver, living related mismatched, living related HLA-identical), donor mismatch at the HLA A, B loci, donor mismatch at the DR loci, preservation time, kidney association (pancreas transplant alone, simultaneous pancreas and kidney transplant, pancreas after kidney transplant), whole versus segmental pancreatic transplant, graft duct management technique (polymer injection, enteric drainage, stomach drainage, bladder drainage), and immunosuppression. By stepwise, logistic regression analysis, we found that the following factors were predictive for 1-year graft function: donor mismatch at the DR loci (P = 0.0003), kidney association (P less than 0.0001), type of donor (P = 0.04), and immunosuppression (P = 0.0002). For donor mismatch at the DR loci, we found an odds ratio for success of 2.2 for 0 versus 2 mismatches. The odds for success were 2.9 for simultaneous pancreas and kidney transplant versus pancreas transplant alone. The best results--79% 1-year graft survival--were obtained for the combination of 0 mismatches at the DR loci, pancreas after kidney transplant, living related HLA-identical donor, and the immunosuppressive regimen consisting of cyclosporin, azathioprine, and prednisone. Patients receiving a pancreas transplant alone with 0 mismatches at the DR loci, living related HLA-identical donor, and triple immunosuppressive regimen had a predicted 1-year graft survival of 71%.

Graft Rejection↗

PubMed2005

Determinants of early discontinuation of IUCD use in rural northern district of India: a multivariate analysis and its validation.

The purpose of this study was to examine the determinants for early discontinuation among IUCD users in a rural district of northern India. Multivariate analysis indicated several significant predictors of early discontinuation of IUCD use. The risk of discontinuation increased more than two times in the presence of factors such as more than usual amount of menstrual flow before insertion and intermenstrual bleeding after insertion. Similarly, residence or alternatively those coming from villages without health centres were nearly two times more likely to discontinue. Menstrual disturbance increased the risk nearly three-fold. If only those women who report normal menstrual cycles had IUCDs inserted, it is very likely that the high discontinuation rate due to menstrual disturbance could be reduced. Knowledge about the IUCD and its effectiveness decreased the risk of early discontinuation but was not a statistically significant factor in multivariate analysis. Validation of the developed model was done by using the bootstrapping method and the model was found to be 18% noisy. These findings may help family planning providers in counselling and practice.

Adult↗

PubMed1992

Hypothyroidism following radiotherapy for head and neck cancer: multivariate analysis of risk factors.

The incidence of hypothyroidism following radiotherapy for head and neck cancer is 10-45% in several series. In order to identify possible risk factors a multivariate analysis was performed in 221 patients previously treated with either radiotherapy alone or combined with surgery or chemotherapy. Diagnostic procedures included: total T3 and T4, free T4 and TSH measured by radioimmunoassay, and thyroid scintigraphy. The absolute rate of hypothyroidism was 41.17% (subclinical 26.24%, clinical 14.93%). No thyroid nodules were detected in any patient. By multivariate analysis, risk factors that significantly influenced a higher incidence of hypofunction were: high radiation dose (p = 0.000), combination of radiotherapy and cervical surgery (p = 0.003), time from therapy (p = 0.022) and no shielding of midline (p = 0.026).

Cobalt Radioisotopes↗

PubMed2003

Improved accuracy in estimation of left ventricular function parameters from QGS software with Tc-99m tetrofosmin gated-SPECT: a multivariate analysis.

UNLABELLED: The purpose of this study was to verify whether the accuracy of left ventricular parameters related to left ventricular function from gated-SPECT improved or not, using multivariate analysis. METHODS: Ninety-six patients with cardiovascular diseases were studied. Gated-SPECT with the QGS software and left ventriculography (LVG) were performed to obtain left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV). Then, multivariate analyses were performed to determine empirical formulas for predicting these parameters. The calculated values of left ventricular parameters were compared with those obtained directly from the QGS software and LVG. RESULTS: Multivariate analyses were able to improve accuracy in estimation of LVEF, EDV and ESV. Statistically significant improvement was seen in LVEF (from r = 0.6965 to r = 0.8093, p < 0.05). Although not statistically significant, improvements in correlation coefficients were seen in EDV (from r = 0.7199 to r = 0.7595, p = 0.2750) and ESV (from r = 0.5694 to r = 0.5871, p = 0.4281). CONCLUSION: The empirical equations with multivariate analysis improved the accuracy in estimating LVEF from gated-SPECT with the QGS software.

Adolescent↗

PubMed1997

[Multivariate analysis of the problems of long-term levodopa therapy in Parkinson's disease].

We investigated clinical features of adverse reactions to long-term levodopa therapy by the multivariate analysis. Dyskinesia, wearing off effect, on-off effect, mental symptoms, and frozen gait were noted in 29 (11.2%), 78 (30.0%), 17 (6.5%), 45 (17.7%), and 52 (20.0%), respectively, of 260 patients with Parkinson's disease to whom levodopa had been administered for over one year. In the statistical investigation by the multivariate analysis (quantification method type II), the age of initial levodopa therapy, the duration from the onset to the initiation of levodopa therapy, and the duration of levodopa therapy were not closely related to the development of any adverse reaction, while Hoehn & Yahr's stage and the dosage of levodopa had the most significant influence on the development of adverse reactions. Furthermore, concomitant use of amantadine hydrochloride produced an inhibitory effect on the development of dyskinesia. We conclude that early institution of levodopa therapy in Parkinson's disease may not be an important risk factor of adverse reactions.

Adult↗

PubMed2004

Predictive factors for recurrence after thyroid lobectomy for unilateral non-toxic goiter in an endemic area: results of a multivariate analysis.

BACKGROUND: The aim of the study was to identify the factors that are predictive of recurrence after thyroid lobectomy for unilateral non-toxic thyroid goiter in an endemic region through a multivariate analysis. METHODS: Two hundred sixty-eight consecutive patients who underwent thyroid lobectomy and who were evaluated by the same endocrinologist were included. Univariate and multivariate analysis analyzed the relationship between sex, age, preoperative thyroid-stimulating hormone, duration of disease, duration of levothyroxine (LT4) preoperative therapy, cytologic results, histologic results, resected thyroid weight, numbers and diameters of thyroid nodules, morphologic alterations of the remnant lobe, follow-up length, postoperative LT4 therapy, ultrasonographic evidence of recurrence, and reoperation. RESULTS: The incidence of recurrence was 33.9% (91/268 patients) after a mean follow-up time of 79.9 months (range, 12-251 months), female sex ( P = .016), multiple nodules ( P = .017), and lack of postoperative LT4 therapy ( P = .0009) were predictive factors of recurrence. Reoperation was performed in 20 patients (7.4%); factors that were predictive of reoperation were the presence of multiple nodules ( P = .008), resected thyroid weight ( P = .00006), and lack of postoperative hormonal therapy ( P = .0005). CONCLUSIONS: Thyroid lobectomy for unilateral non-toxic goiter, when combined with suppressive or substitutive thyroxin therapy, resulted in a low rate of recurrence and reoperation in an endemic area.

Adult↗