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Observations on Indian node-negative breast cancer patients: a multivariate analysis.

The modern treatment of breast cancer has evolved over the past 100 years based on clinical observations. Therapeutic principles, from the choice of surgical procedure to the management of disseminated disease, have also changed. The axillary tumour burden, that is, the number of histologically positive nodes (N+) plays an important role as a prognostic factor. However, in histologically Negative nodes (N-), it is necessary to discriminate individuals at high risk despite negative nodes. This presentation analyses retrospectively the prognostic factors for long-term failures in N- patients. These prognostic factors need to be studied in detail, and controlled clinical trials should be carried out to detect high risk N- patients and consider them for adjuvant chemotherapy.

Antineoplastic Agents↗

Multivariate analysis of determinants of bacterial contamination of whole-blood donations.

BACKGROUND AND OBJECTIVES: Introduction of bacteria into blood components at the collection stage seems to be a frequent occurrence. We therefore assessed determinants of bacterial contamination of whole-blood donations to gain insight into contamination mechanisms and direct prevention. MATERIALS AND METHODS: A cross-sectional study was carried out on donors accepted for whole-blood donation in four French blood banks. Each blood bank used its own two-stage procedure for phlebotomy site preparation. Contamination was identified by culturing two 15-ml samples (collected aseptically at the outset of donation) in a BacT/Alert 240 system. Determinants were assessed by logistic regression analysis. RESULTS: Bacterial contamination, mainly by skin flora, occurred in 76 (2.2%) out of 3385 donations. Significant determinants were as follows: the blood bank (odds ratio [OR] range = 3.0-5.6, P < 0.001); lack of repetition of scrub (OR = 2.7, P = 0.032); and donor age > 35 years (OR = 1.8, P = 0.036). CONCLUSION: Systematic scrub repetition should be implemented to reduce bacterial contamination by skin flora at the collection stage. Further research is required to clarify the role of different antiseptic agents and of donor age.

Adult↗

Prior trimethoprim use and trimethoprim-resistant urinary tract infection: a nested case-control study with multivariate analysis for other risk factors.

Trimethoprim resistance is increasingly prevalent in community-acquired urinary infections. The objective of this study was to evaluate the association between exposure to community-prescribed trimethoprim and other risk factors in subjects and subsequent trimethoprim-resistant urinary tract infection. The design was a nested case-control study using a record-linkage database. Study subjects submitted a urine sample to the Ninewells Hospital Laboratory between July 1993 and December 1995. Antibiotic exposure in subjects with trimethoprim-resistant isolates (cases) was compared with antibiotic exposure in subjects with trimethoprim-susceptible isolates (controls). Study subjects were drawn from the catchment area of a large teaching hospital in Tayside, Scotland. There were 13765 males and females aged 1-106 years who submitted their first urine sample for culture during the study period. After adjustment for significant risk factors and confounding variables, logistic regression analysis showed exposure to trimethoprim [odds ratio (OR) 4.35] or any antibiotic other than trimethoprim (OR 1.32) to be predictive of resistance. The growth of Proteus spp. (OR 115.14) and bacterial growth other than Escherichia coli and Proteus spp. (OR 2.83) were also predictor variables. Hospitalization in the previous 6 months was not independently associated with trimethoprim resistance. In conclusion, trimethoprim resistance was independently associated with exposure to trimethoprim and to antibiotics other than trimethoprim. Reduction in trimethoprim prescribing alone may not reduce the prevalence of trimethoprim resistance.

Anti-Infective Agents, Urinary↗

[Multivariate analysis of relationship between breast feeding and infant physical development].

Longitudinal analysis with generalized estimating equation (GEE) revealed breast feeding can promote infant physical development and growth, and cross-sectional analysis with canonical correlation showed protein intake with breast milk as its main source brought about infants to develop physically tall and lean at first, which might support the theory that protein intake affects more on their development and growth. The extent of infant physical development and growth varied with the amount of breast milk of his or her mother, which should be caught attention in comparison of infant physical development with different feeding patterns. It is suggested that intervention of breast feeding should be implemented during perinatal period and 1-2 months after delivery with emphasis on health education.

Body Height↗

Surgical technique for totally implantable access ports (TIAP) needs improvement: a multivariate analysis of 400 patients.

BACKGROUND: The objective of this study was to analyze factors that may have an impact on the failure rate of the surgical implantation technique for totally implantable access ports (TIAP) and to assess whether morbidity rates differ between a primarily successful surgical and a secondary Seldinger approach. METHODS: Four hundred consecutive patients receiving a primary TIAP in local anesthesia were included into this retrospective cohort study. A logistic regression-model was used to evaluate reasons for failure of the TIAP method. RESULTS: Three hundred eighteen (79.5%) patients had a successful TIAP procedure, 82 patients were intraoperatively converted to a Seldinger technique. Reasons for failure were: correct positioning impossible n = 54, no or only an undersized vessel for insertion available n = 17, other reasons n = 11. Logistic regression analysis did not reveal any significant factor for failure of the primary surgical approach. In the group with primarily successful TIAP, 8 of 318 patients (3%) developed complications compared to 7 of 82 patients (9%) converted to a Seldinger technique. CONCLUSION: Failure of the surgical approach for implanting totally implantable access ports is related to insertion and positioning. Conversion to a Seldinger technique results in a higher complication rate. A modified approach for surgical port placement should be considered in order to reduce complications.

Aged↗

[Interferon treatment for chronic hepatitis C--assessment of 3 regimens in patients received more than 500MU interferon treatment and their effect predictive factors for interferon treatment using multivariate analysis with the logistic regression model].

Chronic hepatitis C patients (n = 115) were treated with interferon (IFN). Total dose employed was more than 500 MU. The response rate was assessed among the three treatment groups: 2W continuous+TIW, 4W continuous+TIW, 8W continuous+TIW. The IFN treatment effect predictive factors were also assessed. Complete response (CR) rate, CR with serum HCV-RNA disappearance rate, responders' histology activity index score changes between before and after treatment, and responders' hepatocytes HCV-RNA disappearance rate did not differ among the three treatment regimens. CR to IFN treatment was dependent on serum HCV-RNA and HCV serotype. Patients of low serum HCV-RNA and serotype II were responsive to IFN treatment.

Chronic Disease↗

Psychosocial antecedents of injection risk reduction: a multivariate analysis.

The AIDS risk reduction model (ARRM) predicts decreased occurrence of AIDS risk behavior through a three-stage process: (a) perceiving one's behavior as risky and recognizing one's skills to reduce the behavior, (b) forming an intention to change behavior, and (c) acting on that intention. We used the ARRM to test a stage-based longitudinal structural equation model of the impact of intention to reduce injection risk behavior on subsequent behavior change in a sample of 294 HIV-negative opiate-addicted individuals in treatment. Intended risk reduction and continuous participation in treatment significantly predicted less injection risk behavior. Greater self-efficacy, less baseline risk behavior, less perceived susceptibility to AIDS, and greater fear of AIDS predicted intention to reduce risk. Leverage points for change are discussed.

Acquired Immunodeficiency Syndrome↗

Application of multivariate analysis to optimize function of cultured hepatocytes.

Understanding the metabolic and regulatory pathways of hepatocytes is important for biotechnological applications involving liver cells, including the development of bioartificial liver (BAL) devices. To characterize intermediary metabolism in the hepatocytes, metabolic flux analysis (MFA) was applied to elucidate the changes in intracellular pathway fluxes of primary rat hepatocytes exposed to human plasma and to provide a comprehensive snapshot of the hepatic metabolic profile. In the current study, the combination of preconditioning and plasma supplementation produced distinct metabolic states. Combining the metabolic flux distribution obtained by MFA with methodologies such as Fisher discriminant analysis (FDA) and partial least squares or projection to latent structures (PLS) provided insights into the underlying structure and causal relationship within the data. With the aid of these analyses, patterns in the cellular response of the hepatocytes that contributed to the separation of the different hepatic states were identified. Of particular interest was the recognition of distal pathways that strongly correlated with a particular hepatic function. The hepatic functions investigated were intracellular triglyceride accumulation and urea production. This study illustrates a framework for optimizing hepatic function and a possibility of identifying potential targets for improving hepatic functions.

Algorithms↗

Prospective multivariate analysis of factors predictive of complete regression of Barrett's esophagus.

OBJECTIVE: Demographic, endoscopic, and histological features of Barrett's esophagus at initial diagnosis were examined for their ability to predict complete endoscopic and histological regression of Barrett's during long-term follow-up. METHODS: Barrett's patients who have been followed up for a minimum of 2 yr and who have had at least two follow-up surveillance examinations were included in the analysis. Complete regression of Barrett's was defined as total disappearance of all tongues and patches of Barrett's epithelium at endoscopy (confirmed with Lugol's iodine) in conjunction with only squamous epithelium on biopsy. Chi2 and stepwise logistic regression analyses were performed on the following clinical, endoscopic, and histological variables with regards to their ability to predict complete Barrett's regression: patient age in years (<65 or > or =65), length in cm of Barrett's (< or =2, >2<6, and > or =6), presence of a hiatal hernia (yes or no), presence of dysplasia at diagnosis (yes or no), and type of long-term medical treatment (histamine antagonists, proton pump inhibitor [PPI], or PPI and cisapride). RESULTS: Ninety-nine patients, all men with a mean age +/- SD in years of 61.6+/-13.1 have been followed prospectively for 24-106 months (mean +/- SD, 48.0+/-19.8). Seven patients have had complete regression of Barrett's. Univariate analysis showed that complete regression of Barrett's was associated only with absence of a hiatal hernia (p = 0.012). Stepwise logistic regression analysis revealed that complete regression was significantly and independently associated again only with absence of a hiatal hernia (p = 0.025). Stepwise logistic regression analysis utilizing only hiatal hernia (yes vs no) and length of Barrett's (<6 cm vs > or =6 cm) as variables revealed that absence of a hiatal hernia (p = 0.0447) and shorter lengths (<6 cm) of Barrett's (p = 0.0418) were significantly and independently predictive of complete Barrett's regression. CONCLUSIONS: The absence of a hiatal hernia was noted to be the most important factor associated with Barrett's regression. Complete regression of Barrett's esophagus occurs in a minority of patients, primarily in those with no hiatal hernia and shorter lengths of Barrett's epithelium.

Adult↗

Multivariate analysis of risk factors for postoperative complications in benign goiter surgery: prospective multicenter study in Germany.

Risk factors for postoperative complications of benign goiter surgery have not been investigated systematically. To this end, a prospective multicenter study (January 1 through December 31, 1998) was conducted involving 7266 patients with surgery for benign goiter from 45 East German hospitals. High-volume providers (>150 operations per year) performed 69% (5042/7266), intermediate-volume providers 27% (50-150), and low-volume providers 4% (258/7266) of operations. Among the hospital groups, the pattern of thyroid disease did not vary significantly, but there was a trend that small-volume providers tended to perform more operations for uninodular goiter and high-volume providers treated more patients with Graves' disease and recurrent goiter. Extent of resection (p < 0.0001) and remnant size (multinodular goiter and recurrent goiter, p < 0.001), differed significantly, with total thyroidectomy being performed more often in hospitals with more than 150 operations compared to hospitals with an operative volume of less than 150 procedures per year. Despite the larger extent of resection and smaller remnant size, rates of recurrent laryngeal nerve (RLN) palsy or hypoparathyroidism were not increased. When the logistic regression analyses were fitted to evaluate the impact of risk factors on transient and permanent RLN palsy and hypoparathyroidism, larger extent of resection [relative risk (RR) 1.5-2.1] and recurrent goiter (RR 1.8-3.4) consistently evolved as independent risk factors. With hypoparathyroidism, additional significant factors included patient gender (RR 2.1-2.4), hospital operative volume (RR 0.8-1.5), and Graves' disease (RR 2.8). Unlike parathyroid gland identification during hypoparathyroidism, RLN identification (RR 1.6) significantly (p = 0.01) reduced permanent RLN palsy rates. The multivariate analyses clearly confirmed the pivotal role of routine RLN identification, independent of the extent of the thyroid resection. These findings might help hospitals with lower operative volumes to identify patients at increased risk whom they might consider for specialist care.

Adult↗

Multivariate analysis of metastasis risk in laryngeal carcinoma. II. Immune response.

The presence of inflammatory reaction, plasma cells, and eosinophils in peritumoral connective tissue and in neoplastic stroma was evaluated with morphometrical method in 181 patients affected by laryngeal carcinoma. A logistic multiple regression model was applied making it with the use of an independent variable represented by the "infiltrating" or "expansive" types of tumor growth, in order to evaluate the probability of nodal metastatsis of each parameter. The results suggest an inverse correlationship between plasma cells and inflammatory infiltration and incidence of nodal metastatsis only in the comparison of the extreme conditions: those with scarce infiltration versus the ones with large infiltration. Inflammatory or plasmacellular infiltration may represent both a defense mechanism against cancer and an aspecific or allergic reaction. The eosinophilic infiltration shows no value in the prevention of nodal involvement.

Eosinophils↗

[Prognostic factors in colorectal neoplasm. Multivariate analysis in 224 patients].

BACKGROUND: Staging of colorectal carcinoma has prognostic value and allows to take decisions about adjuvant therapy and follow up. Prognostic factors are not universally accepted and there are different staging classifications. AIM: To assess the prognostic value of clinical and pathological variables in 224 patients subjected to a curative resection of a colorectal carcinoma. PATIENTS AND METHODS: A retrospective analysis of 99 men and 125 women, aged 23 to 91 years old subjected to a curative resection of a colorectal carcinoma and followed up for a mean of 72 months. RESULTS: Global survival at 60 months was 72%. Univariate analysis showed that tumor localization, vascular permeation, wall infiltration and number of involved lymph nodes had an influence on survival. A Cox regression model disclosed tumor localization (colon versus rectum), a carcino-embryonic antigen over 30 ng/ml, vascular permeation, presence of 1 to 4 involved lymph nodes, or 5 or more lymph nodes and the presence of an apical lymph node as variables with significant prognostic value. CONCLUSIONS: Our series confirms the prognostic importance of lymph node involvement. This parameter is incorporated in Jass, GITSG (both modifications of Dukes classIfication) and TNM staging scores.

Adenocarcinoma↗

Progression rate to end-stage renal failure in non-diabetic kidney diseases: a multivariate analysis of determinant factors.

BACKGROUND: The respective contribution of the type of nephropathy, gender, and proteinuria, and of the potentially alterable factors blood pressure level and daily protein intake on the rate of progression in non-diabetic renal diseases is debated. METHODS: We retrospectively analysed the influence of primary renal disease, gender, urinary protein excretion, mean arterial pressure (MAP), and dietary protein intake on the rate of decline in creatinine clearance (delta Ccr) in 159 adult patients with well-defined nondiabetic kidney diseases. All patients had been followed from a baseline Crr of 40-50 ml/min/1.73 m2 until endstage renal disease and need for dialysis. RESULTS: Mean (+/- SD) delta Ccr (ml/min/1.73 m2/year) was 9.9 +/- 6.5 in 51 patients (45 males) with chronic glomerulonephritis, 6 +/- 2.5 in 50 patients (26 males) with polycystic kidney disease, 5.5 +/- 2.4 in 17 patients (16 males) with hypertensive angionephrosclerosis, and 3.9 +/- 2 in 41 patients (21 males) with chronic tubulointerstitial nephritis. delta Ccr was higher in males than in females (7.5 +/- 5.2 versus 4.8 +/- 2.5; P < 0.001). Linear regression analysis of the whole population disclosed a strong relationship between delta Ccr and proteinuria (r2 = 0.23; P < 0.001), and a weak relationship between delta Ccr and protein intake (r2 = 0.03; P = 0.02), but no relationship between delta Ccr and MAP (r2 = 0.01; P = 0.23). Stepwise multiple regression analysis identified the type of nephropathy, gender, and proteinuria as independent predictive factors of progression; however, these factors together accounted for only 36% of the variation in delta Ccr, suggesting the contribution of other yet unidentified factors. CONCLUSIONS: Primary kidney disease and urinary protein excretion (reflecting the severity of renal disease in individual cases) appear as the major determinants of the rate of progression, with faster progression in males in all types of nephropathy, whereas potentially alterable factors such as blood pressure and protein intake had only a modest influence in the range of values observed in our patients.

Adult↗

Multivariate analysis of determinants of fetal growth retardation.

OBJECTIVE: To analyse the relative effect of the risk factors related to fetal growth retardation (FGR) in the central area of Spain. STUDY DESIGN: This is a case-control survey of 370 full-term gestations. Of the 370 women, 185 were diagnosed with intrauterine growth retardation, and 185 were in the normal group. All came from a central region of Spain. We took into account 25 possible risk factors. RESULTS: In the FGR group we found 12 risk factors with statistical significance in the univariate analysis (tobacco, drugs, low pre-pregnancy weight, low maternal height, little gestational weight gain, excessive physical activity during pregnancy, low socioeconomic status, low educational level, unmarried, urinary infection, mother's haematological changes, and previous infertility). After the multiple logistic regression analysis, five factors were shown to exist as independent risks (tobacco: OR, 23.50; 95% CI, 3.01-183.18; P < 0.01; low pre-pregnancy weight: OR, 4.01; 95% CI, 2.14-7.51; P < 0.001; low socioeconomic status: OR, 2.91; 95% CI, 1.72-4.90; P < 0.001; little gestational weight gain: OR, 2.52; 95% CI, 1.21-5.22; P < 0.05; and urinary infection: OR, 3.83; 95% CI, 1.49-9.87; P < 0.01). CONCLUSIONS: (i) Tobacco, low pre-pregnancy weight and low socioeconomic status are the three main cause-effect factors of relative importance in our sanitary zone for FGR. (ii) Disproportionate FGR is related more to older mothers and maternal previous illness than to the proportionate FRG.

Body Weight↗

[Multivariate analysis of demographic parameters of the population].

Strong associations between demographic parameters characterizing age, ethnic composition, and migrational processes in the population have been revealed by means of multivariate methods (correlation and cluster analyses; the method of principal components). Formation of the demographic structure of a population has been shown to be related to these associations, their directions and strength. In the long term, these associations determine features of subdivision (territorial, hierarchic, etc.) of the demographic structure of a particular population.

Age Distribution↗

Multivariate analysis of factors influencing the results of restorative proctocolectomy.

Univariate and multivariate analyses have been used to assess the influence of 14 variables on the results of 65 consecutive ileoanal pouch procedures over 5 years. There were nine failures requiring intubation, ileostomy or pouch excision. There was a significant association between failure and pelvic sepsis (P less than 0.05, n = 8), endoanal mucosectomy (P less than 0.05, n = 7), preservation of a long rectal cuff (P less than 0.05, n = 5) and lack of experience with the operation (P less than 0.05, n = 8). Of 49 patients with preoperative evidence of ulcerative colitis, three are now known to have Crohn's disease. Functional outcome was significantly impaired in patients who developed pelvic sepsis (P less than 0.01) or a postoperative fistula (P less than 0.05), and who had an endoanal mucosectomy (P less than 0.05). Success with ileoanal pouch reconstruction increases with experience. Avoidance of sepsis is associated with a lower failure rate, improved functional results and reduced hospital stay. Preliminary colectomy is also advised to exclude Crohn's disease if the diagnosis is in question.

Adult↗

Multivariate analysis of survival, local control, and time to distant metastases in patients with unresectable non-small-cell lung carcinoma treated with 3-dimensional conformal radiation therapy with or without concurrent chemotherapy.

BACKGROUND: Three-dimensional (3D) conformal radiation therapy (CRT) and chemotherapy have recently improved lung cancer management. PATIENTS AND METHODS: We reviewed outcomes in 68 patients with unresectable stage I-III non-small-cell lung cancer. Treatment consisted of 3D CRT alone or with concurrent chemotherapy (CCR). RESULTS: Concurrent chemotherapy improved survival, to a median of 17 months +/- 4.9 months, compared with 8 months+/- 4.1 months for the radiation therapy (RT) alone group (P=0.0347). The 2- and 5-year survival rates were 40.3%+/-7.7% and 14.1%+/-6.4%, respectively, with CCR, compared with 19.6%+/- 9.6% and 0, respectively, for RT alone. In a subgroup analysis for age > 65, patients who received CCR (n=20) had significantly improved survival and local control (P=0.005 and P=0.0286, respectively). Acute esophageal toxicity Radiation Therapy Oncology Group grade >or= 3 was significantly higher in the CCR group and correlated with the RT dose (19% in CCR vs. 0 in RT, P=0.0234; P=0.050). The overall incidences of esophageal and pulmonary toxicity grade >or= 3 were 20.6% and 5.9%, respectively. CONCLUSION: Our study confirms that CCR is associated with improved survival over RT alone, with a tolerable increase in acute toxicity.

Aged↗

[Multivariate analysis of the prognostic and predictive factors of response to concomitant radiochemotherapy in epidermoid cancers of the esophagus. Value of immunodetection of protein p53].

OBJECTIVE: The purpose of this study was to determine the prognostic value of the expression of protein p53, EGF receptors (EGR-R), cell proliferation antigen (Ki67) and DNA analysis by flow cytometry on per-endoscopic biopsies as well as the ability of these factors to predict response to concomitant chemoradiation in patients with squamous cell oesophageal carcinoma. METHODS: Sixty-two patients with squamous cell oesophageal carcinoma were prospectively included in this study. For 58 patients (51 men, 7 women; mean age: 59.1 +/- 9.3 years), clinical response to chemoradiation was correlated with the findings of flow cytometry (ploidy, % of cells in S-phase) and immunohistochemistry (p53, EGF-R, Ki67). There were 4 patients in stage I, 14 in stage II, 27 in stage III, and 13 in stage IV. Chemoradiation (2 cycles associating continuous 5FU 800 mg/m2/24 h from D1 to 5 and from D22 to 26, Cisplatyl 70 mg/m2 on D1 and D22; 15 Gy/5d from D1 to 5 and from D22 to 26), was performed prior to surgery in 19 patients (group I) and as the only treatment in 39 patients (group II), with a third cycle from D43. Clinical response was defined as complete or incomplete, ascertained by endoscopy and biopsy, 2 to 3 weeks after the end of chemoradiation. RESULTS: Mean survival in all 58 patients was 13.0 months. Survival was significantly longer in responders than in non responders (14.7 vs 9.6 months; P = 0.03). Among M0 patients, survival was not different in case of exclusive chemoradiation therapy or chemoradiation therapy followed by surgical excision (17.6 vs 13.0 months; NS). Monofactorial analysis showed that, in addition to response, the variables related to survival were stage, non-metastatic status, and absence of p53 surexpression. After multifactorial analysis according to the Cox model, the remaining variables were non-metastatic status, and absence of p53 surexpression. A complete response with negative biopsies was observed in 39 out of 58 patients, i.e. 67.3 +/- 12.1 % (group I: 12 out of 19; group II: 27 out of 39; NS). According to monofactorial analysis, 3 factors were predictive of complete response, i.e. non surexpression of p53 (P < 0.05) and tumour diameter (P = 0.04). After step-by-step logistic regression, non surexpression of p53 and tumour diameter continued to be predictive. The relative risk of a non-complete response was 5.46 if p53 was detected and 1.84 for each cm of added tumour diameter. These two factors were independent. CONCLUSIONS: In this study the predictors of complete response were absence of p53 surexpression and tumour diameter ascertained by CT-scan. Flow cytometry and Ki67 antigen had no prognostic value and were not predictors of response.

Adult↗