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Variables predictive of voiding disfunction following aponeurotic sling surgery: multivariate analysis.

INTRODUCTION: Aponeurotic sling surgeries can evolve with obstruction or voiding dysfunction in 5 to 20% of patients. There are few studies on factors that could possibly predispose to voiding difficulties or urinary retention. The objective of this work is to identify these potential clinical or urodynamic factors. MATERIALS AND METHODS: Records from 130 patients who underwent aponeurotic sling surgeries were reviewed. All patients underwent a throughout urodynamic study during pre-operative investigation. The variables studied were age above 65 years, previous pelvic surgeries, concomitant surgeries, post-voiding residue higher than 100 mL, vesical obstruction (according to Blaivas-Groutz nomogram) and urinary flow under 12 mL/s. Post-voiding residue was assessed on the seventh post-operative day through vesical catheterization. Recovering of spontaneous voiding after 7 post-operative days or with a residue higher than 100 mL, was regarded as voiding dysfunction. Univariate analysis was performed with qui-square test and Fisher's exact test, and multivariate analysis was performed by logistic regression with alpha = 5%. RESULTS: Age in the studied group ranged from 41 to 83 years (mean 56.7 years), with 69 (53%) patients having urethral hypermobility and 61 (47%) having intrinsic urethral lesion. Normal voiding occurred in 97 (75.6%) women with 7 post-operative days. The only significant variable in the univariate (p = 0.014) and multivariate (p = 0.017) analysis was post-voiding residue higher than 100 mL. CONCLUSION: Pre-operative presence of a post-voiding residual urine higher than 100 mL was the only variable predictive of voiding dysfunction.

Adult↗

Subjective multivariable analysis bu computer for evaluation of coronary artery bypass.

Subjective multivariable analysis by computer was utilized to evaluate the results in a series of 659 patients undergoing coronary artery saphenous vein bypass surgery. A video terminal gave access to a remote computer. The postoperative subjective response was evaluated by questionnaires sent to patients at 6- to 12-month intervals, and was augmented by treadmill testing and postoperative coronary arteriography. Operative risk and subjective response are related only to the degree of ventricular function lost prior to surgery. Long-term results were best in patients in whom complete revascularization was possible. Current operative risk is less than 1%; a five-year survival rate of 90% to 95% is predicted. More than 90% of patients were asymptomatic or "greatly improved." Postoperative treadmill tests were negative in 88% of patients in these groups. In patients who were only "slightly improved" or "not improved," repeat catherization showed a graft patency rate of 84%, suggesting that recurrent symptoms were related to the extent of preoperative disease or to the progression of disease in nongrafted vessels, rather than to graft occlusion.

Computers↗

Studies of codon usage and tRNA genes of 18 unicellular organisms and quantification of Bacillus subtilis tRNAs: gene expression level and species-specific diversity of codon usage based on multivariate analysis.

We examined codon usage in Bacillus subtilis genes by multivariate analysis, quantified its cellular levels of individual tRNAs, and found a clear constraint of tRNA contents on synonymous codon choice. Individual tRNA levels were proportional to the copy number of the respective tRNA genes. This indicates that the tRNA gene copy number is an important factor to determine in cellular tRNA levels, which is common with Escherichia coli and yeast Saccharomyces cerevisiae. Codon usage in 18 unicellular organisms whose genomes have been sequenced completely was analyzed and compared with the composition of tRNA genes. The 18 organisms are as follows: yeast S. cerevisiae, Aquifex aeolicus, Archaeoglobus fulgidus, B. subtilis, Borrelia burgdorferi, Chlamydia trachomatis, E. coli, Haemophilus influenzae, Helicobacterpylori, Methanococcusjannaschii, Methanobacterium thermoautotrophicum, Mycobacterium tuberculosis, Mycoplasma genitalium, Mycoplasma pneumoniae, Pyrococcus horikoshii, Rickettsia prowazekii, Synechocystis sp., and Treponema pallidum. Codons preferred in highly expressed genes were related to the codons optimal for the translation process, which were predicted by the composition of isoaccepting tRNA genes. Genes with specific codon usage are discussed in connection with their evolutionary origins and functions. The origin and terminus of replication could be predicted on the basis of codon usage when the usage was analyzed relative to the transcription direction of individual genes.

Archaea↗

Community integration of young adults with mental retardation: a multivariate analysis of adjustment.

The purpose of the present study was to determine whether differences in community adjustment existed for three groups of young adults with mental retardation using data organized on the basis of four empirically validated factors identified in prior research. A descriptive discriminant function analysis was used as a follow-up to a statistically significant multivariate analysis of variance F-ratio. Results obtained from the discriminant analysis indicated that five variables (number of limiting factors, earned income, number of support services, living arrangement, number of daytime activities) contributed substantively to separation of the three group centroids.

Activities of Daily Living↗

Multivariate analysis of genetic and acquired factors; T235 variant of the angiotensinogen gene is a potent independent risk factor for preeclampsia.

Preeclampsia is known to be a multifactorial disease. Recently, the angiotensinogen gene has been shown to be a candidate gene that could be related to preeclampsia, and acquired factors such as lifestyle during pregnancy have also been considered to be risk factors. The aim of this study was to investigate the interrelations among the angiotensinogen gene and various acquired risk factors in preeclampsia. Fifty-eight primiparous patients with pre-eclampsia were compared with 164 normal primiparous controls. A variant of the angiotensinogen gene (M235T) was analyzed along with the acquired factors obtained from both medical records and a questionnaire consisting of 98 questions. Univariate analysis disclosed 11 factors that were significantly associated with preeclampsia (P < .05). Multivariate analysis revealed four significant independent factors: "prepregnancy high body mass (body mass index > or = 24)," "T235 homozygotes of the angiotensinogen gene," "mentally stressful condition during pregnancy," and "salty dishes preferred during pregnancy." The odds ratios of the four factors were 6.2, 2.5, 3.0 and 2.6, respectively, in a multiple logistic model. Our results support the concept that T235 of the angiotensinogen gene is a potent, independent risk factor for preeclampsia, as well as other lifestyle-related risk factors.

Adult↗

Treatment of oesophageal perforation: a multivariate analysis.

Perforation of the oesophagus was retrospectively analysed in 59 patients. Cause and extent of perforation, localization, quality of the oesophageal wall and therapeutic modes were subjected to univariate analysis. The perforations of the intrathoracic oesophagus (39) were also subjected to multivariate analysis. Perforation of the cervical oesophagus is seldom lethal and can be adequately treated conservatively in the majority of cases. Perforations of the intrathoracic oesophagus can be divided into two groups, with or without simultaneous perforation of the parietal pleura. The optimal treatment for the group with pleural perforation seems to be resection of the oesophagus and secondary reconstruction, although primary closure is indicated in selected early cases. Perforations of the intrathoracic oesophagus confined to the mediastinum can be adequately treated conservatively in most patients. Perforation of the intra-abdominal oesophagus should be treated like any other intra-abdominal visceral perforation, by closure or diversion, even if this results in resection of the oesophagus.

Adolescent↗

The Swedish Childhood Diabetes Study--a multivariate analysis of risk determinants for diabetes in different age groups.

In a nationwide incident case-referent study stepwise univariate analysis has revealed several risk determinants for childhood diabetes mellitus. In a multivariate analysis we have determined the set of risk determinants that would independently predict childhood Type 1 (insulin-dependent) diabetes. Possible interactions between the risk determinants and differences in risk profiles with different ages at onset were also examined. Reported familial insulin-treated and non-insulin-treated diabetes were significant risk factors in all age groups, as was also a low frequency of milk intake. The frequency of infections and a high intake of foods rich in nitrosamine tended to interact (OR 11.8, p = 0.053) indicating a synergistic effect. A Cox regression analysis revealed that stressful life events during the last year was the only variable that tended to affect the age at onset (p = 0.055). This indicated that psychological stress may rather precipitate than induce Type 1 diabetes. A short breast-feeding duration (OR = 3.81), and an increased body height (OR = 3.82) contributed significantly to the predictive model in only the youngest age group (0-4 years). An increased frequency of infections in the year preceding onset (OR = 2.15) and no vaccination against measles (OR = 3.33) contributed significantly to the model only in the age group 5-9 years. Various nutrients had different impacts on the risk of developing Type 1 diabetes in different age groups. It is concluded that in the genetically susceptible child, risk factors which are associated with eating habits, frequency of infections, vaccination status, growth pattern and severe psychological stress affect the risk of developing diabetes independently of each other.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

Multivariate analysis of operative mortality and late outcome after coronary bypass surgery.

A multivariate discriminant analysis was made to find out the variables that could offer the greatest amount of predictive power on the long term results after myocardial revascularization. A total of 202 consecutive patients who underwent CABG operation in 1981 were reviewed 5 years later. Most of the patients (76.5%) had 3-vessel disease, previous AMI (70.2%), hypertriglyceridemia (61.7%), positive family history of CAD (68.0%) elevated blood cholesterol level (48.1%), hypertension (41.9%) or were smokers (61.9%). In 48.1% of the cases IMA was used for revascularization and in the rest saphenous vein graft alone. The 5-year survival of the entire group was 87%. The late mortality was related to 3 independent variables in multivariate analysis: 1) positive family history of CAD (p less than 0.05), 2) preoperative ejection fraction less than 0.30 (p less than 0.01) and 3) revascularization without IMA (p less than 0.02). The vast majority of patients (70%) had a better NYHA class 5 years postoperatively (the 95% confidence interval was 65-77%). These patients had experienced an average improvement of 2.0 NYHA categories. Eight per cent of patients had an unaltered and 5% a worse NYHA class than preoperatively. When the patients were grouped into those having a better NYHA class and into those who had an unchanged or worse NYHA class or who had died from CAD the only variable which was associated with poorer outcome appeared to be positive family history of CAD (p less than 0.01). It can be concluded that hereditary factors, utilization of internal mammary artery in revascularization and preoperative ejection fraction are the major predictors of late outcome after CABG.

Coronary Artery Bypass↗

Value of flow cytometric determination of ploidy as a guide to prognosis in operable rectal cancer: a multivariate analysis.

The DNA content of 203 cases of rectal cancer, with at least 15 years follow-up, was analysed by flow cytometry. One hundred and twenty-nine (64%) were DNA aneuploid and corrected survivals were significantly influenced by ploidy distribution (p less than 0.01). The DNA content and details of stage and grade were subjected to multivariate analysis using the Cox regression model. Ploidy was entered into models including Dukes' stage alone, tumour differentiation alone, Dukes' stage and differentiation in combination and a more comprehensive range of discrete stage- and grade-related parameters. All four models demonstrated its independent contribution to survival. However, its contribution was very small (5%, 18%, 5%, 4% respectively). These findings illustrate that results based on new technological developments should not be viewed in isolation, but their values must be assessed in combination with traditionally available data by means of multivariate analysis.

Adenocarcinoma↗

Transitional cell carcinoma of the urethra in men following cystectomy for bladder cancer: multivariate analysis for risk factors.

Multicentric development of transitional cell carcinoma in the urinary tract is well recognized. Of 169 male patients who underwent cystectomy for bladder cancer 18 (10.6%) demonstrated urethral cancer (all within 5 years after cystectomy). The risk factors involved in transitional cell carcinoma in regard to the occurrence of urethral cancer after cystectomy were examined by multivariate analysis. Characteristic patterns of bladder cancer in the cystectomy specimens were expressed by the grade, stage, number, size, location and gross pattern of the tumors. Significant risk factors in bladder cancer relating to the development of cancer in the retained urethra were papillary cancer, multiple cancers, and tumors in the bladder neck, prostatic urethra and prostatic gland. Among 19 patients with concomitant carcinoma in situ and/or multiple papillary tumors in the bladder who underwent simultaneous prophylactic urethrectomy with cystectomy in the same observed period 17 (89%) had no lesion in the resected urethra. The results of the multivariate analysis will be useful to avoid unnecessary prophylactic urethrectomy at cystectomy. However, further analysis and consideration of possible mechanisms of the secondary urethral cancer will be necessary to explain the discrepancy posed in the latter study involving 19 patients.

Adult↗

Association between patient age and gabapentin serum concentration-to-dose ratio: a preliminary multivariate analysis.

OBJECTIVES: To evaluate the association between patient age and gabapentin (GBP) concentration-to-dose ratio by a multivariate analysis. METHODS: The association between patient age and the trough steady-state serum concentration of gabapentin (GBP) normalized to 1 mg/kg body weight or concentration-to-dose ratio (CDR) was retrospectively assessed by analysis of covariance. Potential confounding factors considered were GBP dosage, the number of GBP doses per day, and the presence of concomitant antiepileptic drugs (AEDs). Concentrations that had been measured in predose "trough" samples collected from 66 patients, aged 5-84 years, with partial seizures or neuropathic pain chronically receiving GBP BID (n = 21) or TID (n = 45), alone (n = 15) or in combination with other AEDs (n = 51) were used in this retrospective analysis. RESULTS: Average GBP CDR was 0.23 +/- 0.18 (mean +/- SD). The GBP CDR increased with age (r2 = 0.46, P < 0.001), and the correlation was improved when only samples from patients taking GBP BID were separately considered (r2 = 0.68, P < 0.001). The ratio was lower in the 10 children younger than 11 years of age (0.07 +/- 0.05) than in 8 adolescents aged 12 to 18 years (0.14 +/- 0.04), lower than in 35 adults aged 19 to 65 years (0.22 +/- 0.13), and lower than in 13 patients older than 65 years of age (0.45 +/- 0.20) by 1-way analysis of variance (F = 19.4, P < 0.001). Analysis of covariance showed a significant influence on GBP CDR of patient age (P < 0.001) and the number of GBP daily doses (P < 0.01), but GBP daily dosage or concomitant AEDs had no significant influence on the ratio. CONCLUSIONS: In this retrospective study of a small, select group of patients, (1) the GBP CDR increased significantly with age when potential confounding factors such as GBP dosage, number of GBP doses per day, and concomitant AEDs were considered by analysis of covariance, and (2) patients older than 65 years, even without any known renal disease, may have double GBP CDR than younger adults and, therefore, may need half of the GBP dose per body weight to achieve a similar concentration.

Adolescent↗

Prognosis of dilated cardiomyopathy: from a retrospective to a prospective study employing multivariate analysis.

To determine the prognostic factors of dilated cardiomyopathy (DCM), a retrospective long-term investigation of 111 patients seen between 1967 and 1983 was carried out. Fifty-four deaths were divided into 3 subgroups: (1): sudden death (n = 6); (2): sudden death on the basis of heart failure (n = 17); (3): refractory heart failure death (n = 31). Multivariate analysis was employed to ascertain the prognostic score, which was constructed from the grading of the New York Heart Association functional classification, the cardiothoracic ratio, electrocardiographic findings and cardiac function. Individual variables were indicated on the first (I) and second (II) principal component axes. The mean center points for the death modes were as follows: (1): I = -0.4, II = +0.8, (2): I = +0.7, II = +1.1, (3): I = +1.4, II = -0.8. Surviving cases (n = 57) showed I = -0.6, II = +0.1. Forty-one cases examined during 1984-1985 were analyzed to evaluate the prognostic efficacy of this score. Fourteen of 17 cases (82%) located in the refractory heart failure death group died within one year after determination of the prognosis, showing thereby that the prognostic determination by multivariate analysis is effective.

Adult↗

The equilibrium unfolding of MerP characterized by multivariate analysis of 2D NMR data.

A general problem when analysing NMR spectra that reflect variations in the environment of target molecules is that different resonances are affected to various extents. Often a few resonances that display the largest frequency changes are selected as probes to reflect the examined variation, especially in the case, where the NMR spectra contain numerous resonances. Such a selection is dependent on more or less intuitive judgements and relying on the observed spectral variation being primarily caused by changes in the NMR sample. Second, recording changes observed for a few (albeit significant) resonances is inevitably accompanied by not using all available information in the analysis. Likewise, the commonly used chemical shift mapping (CSM) [Biochemistry 39 (2000) 26, Biochemistry 39 (2000) 12595] constitutes a loss of information since the total variation in the data is not retained in the projection into this single variable. Here, we describe a method for subjecting 2D NMR time-domain data to multivariate analysis and illustrate it with an analysis of multiple NMR experiments recorded at various folding conditions for the protein MerP. The calculated principal components provide an unbiased model of variations in the NMR spectra and they can consequently be processed as NMR data, and all the changes as reflected in the principal components are thereby made available for visual inspection in one single NMR spectrum. This approach is much less laborious than consideration of large numbers of individual spectra, and it greatly increases the interpretative power of the analysis.

Fourier Analysis↗

Multivariate analysis of trace metals in textile effluents in relation to soil and groundwater.

This paper deals with the multivariate analysis of metal data in effluents, soil and groundwater to find the distribution and source identification of the selected metals in the three media. Samples were collected from three textile industries located in Hattar Industrial Estate, Pakistan. Metals were estimated by flame atomic absorption spectrophotometry. The results showed elevated levels of Cr, Pb, Ni, Co, Fe, Ca, Na, K and Zn in these media, following the order: soil>effluent>water. Principle component analysis (PCA) of the data showed that the textile effluents are contaminating the soil wherein Cr and Pb were dominant toxic metals having concentrations of 5.96 mg/kg and 4.46 mg/kg, respectively. Other toxic metals such as Co, Cd, Zn, Ni, Mn and Fe, were found to have common origin in the textile effluents. The correlation study along with linear regression and PCA, supported the fact that various elevated metal concentrations emerged from the textile industrial effluents ultimately leading to contamination of the soil and groundwater in their proximity. The estimated metal levels in the water/soil system are compared with the safe limits laid down by WHO.

Environmental Monitoring↗

[The combination assay of tumor markers by multivariate analysis for improvements of the diagnostic precision in malignancies].

Since 1987, we have been trying to develop a computer-aided multivariate pattern analysis system (CAMPAS) with the focus on ovarian tumors using a discriminant analysis, which is one of multivariate analysis, to raise specificity while retaining sensitivity of combination assay as high as possible. We applied this CAMPAS which was developed in collaboration with SRL (Tokyo, Japan) under the guidance of Prof. Em. Terashima, Y.(The Jikei University School of Medicine, Tokyo, Japan). CAMPAS OV-2, which is the newest one, based on 2 discriminant formulas with 6 tumor markers, ie, cancer antigen 125 (CA125), immunosuppressive acidic protein (IAP), tissue polypeptide antigen (TPA), alkaline phosphatase (ALP), albumin and iron (Fe), was developed and practised prospectively as a pretherapeutic serological diagnostic means to distinguish epithelial ovarian carcinomas from benign ones tumors. The sensitivity and specificity reached 87.1% and 82.9%, respectively in CAMPAS OV-2.

Biomarkers, Tumor↗

Factors influencing incidence and extension of metachronous liver metastases of colorectal adenocarcinoma. A multivariate analysis.

BACKGROUND/AIM: Three hundred and eighty-seven patients surgically treated for colorectal adenocarcinoma were assessed by a multivariate analysis and the factors influencing incidence and extension of metachronous liver metastases studied. METHODOLOGY: A series of 387 patients which had been surgically treated for colorectal adenocarcinoma between January 1980 to December 1990 and followed-up over a minimum of a 5-year period was retrospectively studied. RESULTS: The most reliable prognostic markers are represented by tumor site (p < 0.05) and, more specifically, by wall infiltration (p < 0.01) and metastatic lymph-nodes (p < 0.05). The only independent variable with a significant impact on stage of metachronous liver metastases was proved to be the depth of wall infiltration (p < 0.05). CONCLUSION: This study confirms the reliability of some indicators of primary tumor in influencing incidence, but not extension, of metachronous liver metastases and this is the main problem when it comes to using prognostic factors in order to modulate the intervals of postoperative follow-up according to risk category.

Adenocarcinoma↗

[Utility of multivariate analysis in evaluating the results of health examination on the basis of intra-individual variations].

Utility of multivariate analysis in evaluating the values of laboratory tests on the basis of intra-individual variations (IV) was studied. Periodic health examination on workers has many clinical laboratory tests and these values are generally evaluated in comparison with "normal ranges." Recently it has been ascertained that the individual normal ranges were narrower than the populational normal ranges. Although the values of an individual should be estimated with normal ranges of the individual, it is almost impossible to determine the normal ranges from only one or two health examinations conducted per annum at the place of work. The author in his study could easily determine IV with a method using Mahalanobis' distance on a basis of populational normal range. In this method, if many values of a person in the tests vary in several years, the distance becomes larger, and if a value in a test falls outside the normal limit, it also becomes larger. This method makes it possible to detect not only an "abnormal" value out of the normal range but also a large value out of IV. To examine the practical validity of the method, the data of 24 employees (males, 45 to 65 years old) from 3 periodic health examinations and those of 20 persons (males, 48 to 71 years old) from 3 to 6 medical checkups were analyzed with regard to 11 items. It was found that 33 out of 44 persons were abnormal in one or more items and that 10 abnormal persons had large IV. They would be missed in the judgement with the use of only "normal ranges." As the distances were computed by a portable computer with a basic program, the method can be easily used in a small place of work. It is considered that this new method is effective and valuable not only as the screening procedure but also in the evaluation of IV.

Aged↗

The tall-cell variant of papillary thyroid carcinoma: a multivariate analysis of clinical risk factors.

BACKGROUND: The biological behaviour of the tall-cell variant (TCV) of papillary thyroid carcinoma (PTC) remains to be clarified in a multivariate analysis that controls for all relevant clinicopathological parameters. PATIENTS AND METHODS: A retrospective analysis was carried out of 332 consecutive PTC patients operated on at a university hospital between November 1994 and February 2003. RESULTS: A total of 16 TCV tumours (4.8%) was identified among the 332 PTC patients. Nodal and (predominantly pulmonary) distant metastases were identified at surgery in, respectively, 50% and 31% of TCV tumours. On univariate analysis, only the association between the TCV and distant metastasis retained statistical significance after adjustment for multiple testing. On multivariate logistic regression analysis, the presence of distant metastasis increased more than fourfold [odds ratio (OR) 4.2] the chance of having the TCV of PTC, with controls for extrathyroidal extension, nodal metastasis, operation status, patient gender, categorized patient age, and categorized primary tumour diameter. CONCLUSION: The increased risk of distant metastasis associated with the TCV morphology of PTC warrants an extensive post-operative search for distant metastasis to facilitate early diagnosis and treatment of tumour deposits in distant organs.

Carcinoma, Papillary↗