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At least 973 records · Page 54Linked to original sources
PubMed2002

Multivariate regression analysis on early mortality after orthotopic liver transplantation.

AIM: To identify the risk factors relating to early mortality after orthotopic liver transplantation. METHODS: Clinical data of 37 adult patients undergoing liver transplantation were retrospectively collected and divided into two groups: the survived group and the death group (survival time<30 d). The relationship between multivariate risk factors and early mortality after orthotopic liver transplantation were analyzed by stepwise logistic regression. RESULTS: The survival rate was 73%. Early mortality rate was 27%. APACAE III, preoperative serum creatinine level and interoperative bleeding quantity had a significant independent association with early mortality. (R=0.1841, 0.2056 and 0.3738). CONCLUSION: APACHE III,preoperative serum creatinine level and interoperative bleeding quantity are significant risk factors relating to early mortality after orthotopic liver transplantation. To improve the recipient's preoperative critical condition and renal function and to reduce interoperative bleeding quantity could lower the early mortality after orthotopic liver transplantation.

APACHE↗
PubMed2006

Logistic regression analysis of pregnancy rate following transfer of Bos indicus embryos into Bos indicus x Bos taurus heifers.

Factors affecting pregnancy rate of 5627 Zebu embryos in crossbred females with unknown proportions of Holstein and Zebu breeding were examined. After evaluation for developmental stage, quality, and viability, embryos were immediately transferred to recipients. Pregnancy diagnosis was conducted approximately 53 d after transfer; pregnancy rate was coded as a binomial event and analyzed using logistic regression models. Maximum likelihood methodology and the likelihood ratio statistic were used to estimate regression coefficients and test hypotheses. Explanatory variables were year of transfer (1992-1999), season of transfer (summer, autumn, winter and spring), breed of the embryo (Guzerat, Gyr or Nellore), stage of the embryo (morula, early blastocyst, blastocyst, expanded blastocyst, and hatching blastocyst), quality of the embryo (excellent, good or regular), and donor-recipient synchrony (estrus in the recipient occurred 2-3 d before, 1 d before, the day of, 1 d after, or 2-3 d after estrus in the donor). Average pregnancy rate was 63.7%. Pregnancy rates were not significantly affected by breed of embryo. The best multiple-logistic model to explain the pregnancy result included the effects of year and season of transfer, embryo stage and quality, and estrous synchrony between donor and recipient (P<or=.01). High pregnancy rates occurred when transfers occurred in autumn, early blastocysts or morulae were transferred, and excellent quality embryos were chosen. In addition, pregnancy rates were highest when estrus in the recipient began 1 d earlier than that of the donor.

Animals↗
PubMed2000

Combined transvaginal B-mode and color Doppler sonography for differential diagnosis of ovarian tumors: results of a multivariate logistic regression analysis.

OBJECTIVE: Transvaginal sonography is limited in its ability to assess early stage cancers of the ovary as well as in distinguishing benign processes. As a method for characterization of tumor vascularization, color-coded Doppler sonography may be able to improve the diagnostic accuracy of B-mode sonography. METHODS: Preoperative transvaginal B-mode and Doppler sonography was performed in 63 patients with unclear adnexal lesions prior to operation. Using multiple logistic regression, the independent variables of each procedure were selected and combined to yield a diagnostic flow chart. The diagnostic accuracy of this decision matrix was tested on 257 patients with unclear adnexal tumors. RESULTS: In the 63 adnexal tumors investigated, the diagnostic impact of isolated sonomorphological assessment with evidence of a "solid area" was 78%. Using Doppler sonography, the best discrimination was achieved by displaying the vascular distribution ("central vascularization"). Combining these independent significant variables of the two procedures raised the diagnostic accuracy to 90% (sensitivity 86%, specificity 93%). The validity achieved by this combination was confirmed by the independent application of this method to the 257 adnexal tumors with unclear malignancy status (diagnostic accuracy 93%, sensitivity 92%, specificity 94%). CONCLUSIONS: The combination of sonography and Doppler sonography achieves high and reproducible diagnostic accuracy in preoperative malignancy status assessment of adnexal tumors. The additional use of Doppler sonography can thus provide significant aid both for differential diagnostics of adnexal lesions and for the choice of surgical route in the case of an existing indication for operative therapy.

Adnexal Diseases↗
PubMed1990

A stepwise logistic regression analysis of factors affecting morbidity and mortality after thoracic trauma: effect of epidural analgesia.

Rib fractures and other chest wall injuries can lead to weak ventilation, atelectasis, and even death. Whereas such injuries in young patients are usually well tolerated, relatively minor chest wall trauma can be serious in elderly patients. Epidural analgesia, by improving pain control and ventilatory function, might improve morbidity and mortality rates compared to other forms of analgesia. Stepwise logistic regression was used to compare thoracic trauma patients more than 60 years of age treated with either epidural or parenteral (IV/IM) analgesia. In spite of more severe thoracic trauma in epidural patients as measured by the Abbreviated Injury Score for the chest (epidural = 3.3 +/- 0.1, IV/IM = 2.8 +/- 0.1; p less than 0.05) the use of epidural analgesia was an independent predictor of both decreased mortality (p = 0.0035) and a decreased incidence of pulmonary complications (p = 0.0088). Epidural analgesia has a positive effect on outcome in elderly trauma victims with chest wall injury and is useful in high-risk patients. Increased costs associated with epidural analgesia are minimal and are justified by improvements in outcome.

Age Factors↗
PubMed2004

Quality of life in glaucoma patients: regression analysis and correlation with possible modifiers.

PURPOSE: To verify the quality of life in a Brazilian glaucoma population and the influence of possible modifiers (e.g., visual acuity, visual field impairment). METHODS: Forty-five consecutive patients from CEROF - Federal University of Goias, Brazil were included prospectively in the study. The quality of life was assessed using the Portuguese version of the VFQ. Possible modifiers were evaluated, initially separately with the Spearman's Correlation and then together in a regression model. RESULTS: The mean age was 59.6 +/- 12.4 years. The mean quality of life score was 79 +/- 15 (range 45-100). Age (r = -0.402, p = 0.006), visual acuity in the better eye (r = -0.497, p = 0.001) and in the worse eye (r = -0.608, p < 0.001), Hodapp-Parrish-Anderson visual field grading scale in the better (r = -0.353, p = 0.01) and worse eye (r = -0.387, p = 0.009), visual field Mean Deviation (MD) in the better (r = 0.355, p = 0.01) and worse eye (r = 0.320, p = 0.04) and ability to perform a visual field test in both eyes (r = -0.397, p = 0.007) were significantly correlated with the quality of life scores. However, only age (younger, better quality of life, p = 0.008) and visual acuity in the better eye (direct relation, p = 0.04) were significant in the regression model (r = 0.633, r(2) = 0.401). CONCLUSIONS: The VFQ may be a useful tool to assess the quality of life in glaucoma patients. The preliminary results indicate that age and visual acuity in the better eye are the main factors related to the quality of life in these patients.

Age Factors↗
PubMed1995

Hepatitis B virus, hepatitis C virus and human immunodeficiency virus infection in health care workers: a multiple regression analysis of risk factors.

A seroprevalence survey of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV), was conducted using serum samples obtained from 5813 health care workers (HCWs) in five public hospitals in the Latium region of Italy, during the 1985 vaccination campaign against HBV. The seroprevalences of HBV, HCV and HIV were 23.3% [95% confidence interval (CI) = 22.3-24.4%], 2% (95% CI = 1.6-2.4%) and 0.07% (95% CI = 0.001-0.13%), respectively. In a logistic regression model, sex, increasing age, all job categories vs. physicians, dental treatment in the previous six months, and needlestick injury during the previous year were significantly associated with HBV. Conversely, no occupational and community risk factors, but only history of blood transfusion were significantly associated with HCV. Nevertheless, the documented risk of HCV as well as of HIV transmission through percutaneous and mucocutaneous exposure to blood and body fluids should lead to continued efforts to minimize risks of infection by enhancing the compliance of HCWs with vaccination against HBV and adherence to infection control measures, and by introducing safer devices and techniques.

Adult↗
PubMed2004

Association between maternal age and the likelihood of a cesarean section: a population-based multivariate logistic regression analysis.

BACKGROUND: A majority of studies examining the relationship between advancing maternal age and the likelihood of cesarean section (CS) use data from regional samples or from a limited number of medical institutions. This study uses population-based data from Taiwan to explore the relationship between maternal age and the likelihood of a CS. METHODS: The National Health Insurance Research Database (NHIRD) on registries of medical facilities and board-certified physicians and monthly claim summaries for inpatients were used. In total, 502 524 singleton deliveries were included in the study. Multivariate logistic regressions were performed with the presence of CS as the dependent variable and maternal age (<20, 20-29, 30-34 and >34 years) as the independent variable. The study controlled for maternal indications, institution characteristics, maternal requests and attending physician characteristics. RESULTS: CS rates for the age groups <20, 20-29, 30-34 and >34 years were 17.7, 27.4, 37.4 and 47.5%, respectively. The regression analyses consistently showed that the likelihood of a CS significantly increased with advancing maternal age within each category of complication after adjusting for medical institution characteristics and characteristics of the attending physician. CONCLUSIONS: This study found that, after adjusting for maternal indications, and healthcare institution and physician characteristics, there was a significant relationship between advancing maternal age and an increased likelihood of a CS. This finding, together with the high CS rate of 32.1% in Taiwan, one of the highest reported in the world today, highlights an imperative need to devise interventions to reduce the frequency of CSs.

Adult↗
PubMed1984

Use of logistic regression analysis to improve prediction of prognosis in acute myeloid leukaemia.

The prognostic usefulness of a range of factors has been examined for patients with acute myeloid leukaemia. Although there was a statistical association between some of these factors and remission rate, the association was only partial. To improve the usefulness of the data, multiple logistic regressional analysis was used. The features selected for use in the analysis were age, blood blast count, FAB classification and colony growth pattern. The last three features could be used as categorical variables, since blood blast counts of greater than 100 X 10(9)/1, FAB group 1 and a prolific pattern of colony growth were associated with a low remission rate. Age was used as a continuous variable. Using these features, eight regression groups were defined. Thus when this data for an individual patient is analysed, it is possible to obtain a value for the probability of that patient achieving remission.

Adult↗
PubMed2002

Regression analysis for vortex ring characteristics during left ventricular filling.

A new technique to determine ventricular function is being developed from non-invasive measurements of centerline mitral flow, using color M-mode (CMM) ultrasound. Based on the hypothesis that vortex rings accompanying mitral flow are significant indicators of ventricular filling, we present a technique to determine characteristics of vortex rings created by mitral inflow, including diameter, position and circulation from the CMM derived centerline velocity data. The rings are modeled as vortex filament loops, which induce axial flow. A quasi-Newtonian regression was performed on the velocity data to determine model ring characteristics. Performance of the technique was determined using a synthetic data set with known vortex ring parameters. The algorithm is shown to be insensitive to initial estimates for ring parameters. However, noise in the data can lead to inaccuracy in the derived ring parameters. Further work to increase the accuracy of the regression algorithm and decrease effect of data uncertainty is ongoing.

Blood Flow Velocity↗
PubMed2025

Cardiovascular risk reduction with glucagon-like peptide-1 receptor agonists is proportional to HbA1c lowering in type 2 diabetes: An updated meta-regression analysis incorporating FLOW and SOUL trials.

AIMS: To evaluate relationships of cardiovascular and kidney outcomes with glycemic or bodyweight reductions in randomised placebo-controlled trials of glucagon-like peptide-1 receptor agonists (GLP-1RAs), incorporating data from FLOW and SOUL trials. MATERIALS AND METHODS: PubMed and EMBASE were searched up to 22 August 2025 for placebo-controlled randomized trials of oral or bolus-type, subcutaneous GLP-1RAs reporting major adverse cardiovascular events (MACE; a composite of cardiovascular death, myocardial infarction, and stroke) in adults with type 2 diabetes. The primary outcome was MACE; secondary outcomes included heart failure (HF) and kidney outcomes. Random-effects meta-analyses were followed by meta-regression evaluating associations with HbA1c and bodyweight reduction. RESULTS: A total of 73&#x2009;263 individuals were included from 10 trials (ELIXA, LEADER, SUSTAIN-6, EXSCEL, Harmony Outcomes, PIONEER 6, REWIND, AMPLITUDE-O, FLOW, and SOUL). GLP-1RAs reduced MACE by 14% (hazard ratio: 0.86; 95% CI: 0.82 to 0.91; p <0.001), as well as hospitalisation for HF and the composite kidney outcome (both p <0.001). Meta-regression showed that every 1% extra reduction in HbA1c corresponded to a 27% lower HR for MACE (p&#x2009;=&#x2009;0.015; R2&#x2009;=&#x2009;0.61). While HbA1c reduction was not significantly associated with secondary outcomes, the directionality was consistent with MACE. Bodyweight change was not associated with any of the analysed endpoints, including MACE (p&#x2009;=&#x2009;0.13; R2&#x2009;=&#x2009;0.21). CONCLUSIONS: HbA1c reduction, not bodyweight change, was significantly and proportionally associated with MACE risk reduction. HbA1c lowering may serve as a useful surrogate for the cardiovascular improvements associated with GLP-1RAs in type 2 diabetes.

Humans↗
PubMed2003

Effects of alcohol and tobacco on aerodigestive cancer risks: a meta-regression analysis.

OBJECTIVE: Meta-analysis was used to summarize the published evidence on the associations between alcohol and tobacco consumption and cancers of the oropharynx, pharynx, larynx, and esophagus. The objective was to produce summary risk estimates with uniform methods and on uniform exposure scales so that the magnitudes of the risks could be compared across tumor sites. METHODS: Epidemiologic studies that estimated the effects of alcohol and tobacco consumption on the risk of cancers of the upper aero-digestive tract were identified from the MEDLINE database, 1966-2001. Alcohol and tobacco data were converted into common units (grams/week). For all studies meeting eligibility criteria, effect parameters (slopes) were estimated for both exposures. The exposure-risk slopes for each study were combined, site by site, using random effects meta-regression methods. RESULTS: Fourteen studies met the final selection criteria. The carcinogenic effects of alcohol and tobacco were found to be multiplicative on the relative risk scale. Tobacco appeared to have a much stronger effect on the larynx than on any of the other aerodigestive sites, while alcohol's effect was strongest on the pharynx. The weakest association was that of alcohol and adenocarcinoma of the esophagus--an order of magnitude weaker than that for tobacco and laryngeal cancer. CONCLUSIONS: Meta-analysis was used to combine the results from all available studies, providing a comprehensive summary of the combined effects of alcohol and tobacco on the upper aerodigestive cancers.

Alcohol Drinking↗
PubMedDate not supplied

Helicobacter pylori infection and age on the development of intestinal metaplasia--a multiple logistic regression analysis.

BACKGROUND/AIMS: Both intestinal metaplasia (IM) and Helicobacter pylori (H. pylori) infection have been linked to gastric carcinogenesis in an age-dependent manner. However, their relationship remains ill defined, especially with respect to age. METHODOLOGY: Three hundred and two asymptomatic subjects (167 males and 135 females; mean age 44.3+/-11.1 years) underwent complete endoscopic examination and biopsy at the antrum and the corpus. H. pylori infection was diagnosed according to histopathology and serology, while IM was determined by histopathology. RESULTS: Eighty-four patients (27.8%) had IM, while 185 patients (61.3%) were seropositive to H. pylori. The frequency of IM was higher in patients with gastric ulcer (9/14, 64.3%) than in those with minimal change (68/229, 29.7%) or duodenal ulcer (7/59, 11.9%), both p<0.01. Patients with IM had a higher mean age (49.5+/-14.1 vs. 42.3+/-9.0, p<0.01) and a higher H. pylori prevalence than those without IM (61/84, 72.6% vs. 124/218, 56.9%, p<0.01). The concordance rate of H. pylori infection between histopathologic and serologic diagnosis was lower in patients with IM (67/84, 79.8%) than those without (196/218, 89.9%, p<0.05). Using logistic regression analyses, the development of IM was noted to be independently related to both H. pylori infection (odds ratio=1.97, 95% confidence interval: 1.1(3.53)) and age (odds ratio = 1.93, 95% confidence interval: 1.51(2.47)). CONCLUSIONS: These data suggest that age and H. pylori infection are independent risk factors for the development of IM. Furthermore, H. pylori infection may have been underestimated in patients with IM because of the use of a single method of detection.

Aged↗
PubMed2006

Linear and non-linear regression analysis for the sorption kinetics of methylene blue onto activated carbon.

Batch kinetic experiments were carried out for the sorption of methylene blue onto activated carbon. The experimental kinetics were fitted to the pseudo first-order and pseudo second-order kinetics by linear and a non-linear method. The five different types of Ho pseudo second-order expression have been discussed. A comparison of linear least-squares method and a trial and error non-linear method of estimating the pseudo second-order rate kinetic parameters were examined. The sorption process was found to follow a both pseudo first-order kinetic and pseudo second-order kinetic model. Present investigation showed that it is inappropriate to use a type 1 and type pseudo second-order expressions as proposed by Ho and Blanachard et al. respectively for predicting the kinetic rate constants and the initial sorption rate for the studied system. Three correct possible alternate linear expressions (type 2 to type 4) to better predict the initial sorption rate and kinetic rate constants for the studied system (methylene blue/activated carbon) was proposed. Linear method was found to check only the hypothesis instead of verifying the kinetic model. Non-linear regression method was found to be the more appropriate method to determine the rate kinetic parameters.

Adsorption↗
PubMed2002

Home visits to prevent nursing home admission and functional decline in elderly people: systematic review and meta-regression analysis.

CONTEXT: The effects of home visitation programs to prevent functional decline in elderly persons have been inconsistent, and the value of these programs is controversial. OBJECTIVE: To evaluate the effect of preventive home visits on functional status, nursing home admission, and mortality. DATA SOURCES: Studies published in English, French, German, Italian, or Spanish reporting randomized trials of the effects of preventive in-home visits in older people (mean age >70 years) living in the community were identified through searches of MEDLINE, PSYCHINFO, and EMBASE (January 1985--November 2001). We also searched the Cochrane Controlled Trials Register, checked reference lists of earlier reviews and book chapters, searched conference proceedings and specialty journals, and contacted experts. STUDY SELECTION: We screened 1349 abstracts and excluded those that did not test in-home interventions or in which the mean age of the study population was younger than 70 years. After further exclusions, 17 articles describing 18 trials were analyzed. DATA EXTRACTION: Two reviewers independently screened abstracts. Discrepancies were resolved by consensus with a third reviewer. For each included trial, we extracted data on the study population and the characteristics of the intervention. Two of us extracted information on 3 end points: nursing home admissions, mortality, and functional status. One of us assessed trial quality, including an examination of the method of randomization, blinding of caregivers and research staff ascertaining outcomes, and proportion of patients included in analyses of the 3 end points. DATA SYNTHESIS: The 18 trials included 13 447 individuals aged 65 years and older. The effect on nursing home admissions depended on the number of visits performed during follow-up. The pooled relative risk (RR) was 0.66 (95% confidence interval [CI], 0.48-0.92) for trials in the upper tertile (>9 visits) but was 1.05 (95% CI, 0.85-1.30) in the lower tertile (0-4 visits). Functional decline was reduced in trials that used multidimensional assessment with follow-up (RR, 0.76; 95% CI, 0.64-0.91) but not in other trials (RR, 1.01; 95% CI, 0.92-1.11). Functional decline was reduced (RR, 0.78; 95% CI, 0.64-0.95) in trials with a control group mortality rate in the lower tertile (3.4%-5.8%) but not (RR, 0.98; 95% CI, 0.84-1.13) in those with a control-group mortality rate in the upper tertile (8.3%-10.7%). A beneficial effect on mortality was evident in younger study populations (RR, 0.76; 95% CI, 0.65-0.88 for ages 72.7-77.5 years) but not in older study populations (RR, 1.09; 95% CI, 0.92-1.28 for ages 80.2-81.6 years). CONCLUSION: Preventive home visitation programs appear to be effective, provided the interventions are based on multidimensional geriatric assessment and include multiple follow-up home visits and target persons at lower risk for death. Benefits on survival were seen in young-old rather than old-old populations.

Activities of Daily Living↗
PubMed1993

Linear regressive analysis using prostate-specific antigen doubling time for predicting tumor biology and clinical outcome in prostate cancer.

BACKGROUND: This study was undertaken to calculate the prostate-specific antigen doubling time (PSA-DT) of prostate cancers recurrent after external beam radiation therapy and to investigate if a correlation exists between the PSA-DT and the clinical behavior of prostate cancer as a possible reflection of the tumor doubling time. METHODS: Twenty-two patients treated with external beam radiation between October 1985 and October 1990 for clinical stages B1, B2, and C (T2a, T2b, T3) prostate cancer experienced PSA elevation as their only sign of failure. Serial PSA determinations are available before initiation of any secondary treatment and these have been used to calculate PSA-DT. RESULTS: The results of this study reveal that the PSA-DT is a constant (r > or = 0.98). Mathematically, this means the PSA value is growing exponentially and may represent tumor growth in the exponential phase. Second, the PSA-DT was found to be linearly correlated (r = 0.86) with the interval to clinical relapse after PSA failure. Graphically, the slope of this correlation is equal to the number of PSA-DT (4.5 with 95% confidence interval [3.6]) required before clinical disease manifests after PSA failure. Using this relationship, one can delineate those patients with aggressive tumor biology (PSA-DT < 3.8 months) who require immediate therapeutic intervention versus a relatively indolent tumor biology (PSA-DT > or = 3.8 months) who can be spared the morbidity and expense of androgen deprivation therapy until clinical recurrence manifests. Furthermore, in the pretreatment setting, observation rather than treatment may be indicated for patients with PSA-DT for 18 months or more, because the disease may not become clinically apparent during the patient's lifetime. CONCLUSION: PSA-DT after radiation therapy may reflect the tumor doubling time and has implications in the posttherapy setting regarding the optimal time of intervention with androgen deprivation and in the pretreatment setting regarding the necessity for treatment rather than observation.

Cell Division↗
PubMedDate not supplied

Hypoplastic acute leukemia: review of 70 cases with multivariate regression analysis.

Between 1971 and 1984, 22 of 190 adult patients (11.6 per cent) with acute leukemia seen at the University of Arizona had hypocellular acute leukemia (HAL), defined as lymphoblasts or myeloblasts (plus atypical promyelocytes) of greater than or equal to 30 per cent, but marrow cellularity of the core biopsy or clot section of less than or equal to 50 per cent based on a 1000 point count. These 22 patients with HAL plus the 48 previously published patients with well documented HAL (combined series of 70 patients) were evaluated in detail with multivariate analysis. The median leukocyte count was 2700/microL, hemoglobin of 8.2 g/dl, and platelet count 63,000/microL. Circulating blasts were noted in 27 of 52 patients (52 per cent). Twenty-seven of 34 patients (79 per cent) had abnormal cytogenetics. The overall median survival was 8 months (range: 0.1-48). The median survival for the 22 patients managed with supportive care alone was 4 months, 6 months for the 16 patients treated with non-aggressive induction therapy, and 13 months for the 32 patients treated with aggressive induction therapy (p less than 0.02 versus other categories). Multivariate analysis confirmed that aggressive induction therapy was a major favourable prognostic factor (p = 0.016). Multivariate analysis of the aggressively induced patients revealed that younger patients (less than or equal to 65; p = 0.04) and patients with no AHD (p = 0.09) lived longer. Thus, aggressive remission induction can be attempted in HAL and appears to contribute to prolonged survival especially under age 65 years.

Acute Disease↗