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PubMed1997

Changes during the last decade in clinical parameters of operated lung carcinoma patients of a center for thoracic surgery and the prognostic significance of TNM, morphometric, cytometric, and glycohistochemical properties.

Two sets of patients with potentially curative resection of primary carcinomas operated in the Department of Thoracic Surgery, Thoraxklinik, Heidelberg during the period 1983-1984 (cohort I), and in 1994 (cohort II) were analyzed. The survival of patients, postsurgical TNM-stages, cell types, and exposure to potentially harmful substances were evaluated. In addition, cytometric and morphometric techniques, and various biotinylated markers have been applied to the tissue sections of the 1994 cohort. Cohort I comprised 282 patients (253 men and 29 women), cohort II all in all 171 patients (121 men and 49 women). In cohort I there were 262 heavy smokers, and 28 patients had a history of exposure to harmful environmental substances (asbestos, polycyclic aromates, etc.) compared to 145 smokers and 68 patients who inhaled potentially harmful substances in cohort II. Major changes were also seen in early lung cancer stages (pT1, pN0) which increased in cohort II, and in a decrease in the relative frequency of epidermoid carcinomas in both men and women with corresponding increase in the frequency of adenocarcinoma in both sexes. The median survival of patients operated with advanced tumor stages had remained unchanged, that of early stages (pT1, pN0, pN1) seems to have improved. Within the cytometric features syntactic structure analysis revealed that the current of structural entropy is closely associated with the survival of patients. Of prognostic significance are, in addition, the expression of binding capacities to histoblood group trisaccharides A and H, the presence and the binding of macrophage migration inhibitory factor, and the presence of ligands for the chicken liver galectin CL-16 and the LewisY antigen. Multivariant statistical analysis gave preferential prognostic importance to the glycohistochemical and morphometric parameters relative to the clinical pT and pN stages in survival analysis.

Adenocarcinoma↗
PubMed2006

Investigation of functional gene polymorphisms IL-1beta, IL-6, IL-10 and TNF-alpha in individuals with recurrent aphthous stomatitis.

UNLABELLED: Recurrent aphthous stomatitis (RAS) is characterized by recurrent episodes of oral ulceration in an otherwise healthy individual. Some reports in the literature indicate that RAS may have immunological, psychological, genetic and microbiological bases. OBJECTIVE: The purpose of the present study was to investigate, using binary logistic regression analyses, a possible association between the functional IL-1beta +3954 (C/T), IL-6 -174 (G/C), IL-10 -1082 (G/A) and TNF-alpha -308 (G/A) genetic polymorphism and RAS in a sample of Brazilian patients, using a multivariate statistical analysis. DESIGN: Sixty-four consecutive subjects affected by minor and major forms of RAS and 64 healthy volunteers were genotyped. To investigate the association between the single nucleotide polymorphisms and risk of RAS, binary logistic regression models were fitted. The associations were expressed by odd ratios (ORs) and adjusted for age and gender, with the corresponding 95% CIs. P-values less than 0.05 were considered significant. RESULTS: A significant increase in the IL-1beta and TNF-alpha heterozygous genotypes were associated with an increased risk of RAS development (OR 2.40 and 3.07, respectively), in the multivariate model. CONCLUSION: Our findings demonstrate that polymorphisms of high IL-1beta and TNF-alpha production were associated with an increased risk of RAS development. Our findings also give additional support to a genetic basis for RAS pathogenesis.

Adolescent↗
PubMed2003

Assessment of cardiovascular reactivity by fractal and recurrence quantification analysis of heart rate and pulse transit time.

Methods used for the assessment of cardiovascular reactivity are flawed by nonlinear dynamics of the cardiovascular responses to stimuli. In an attempt to address this issue, we utilized a short postural challenge, recorded beat-to-beat heart rate (HR) and pulse transit time (PTT), assessed the data by fractal and recurrence quantification analysis, and processed the obtained variables by multivariate statistics. A 10-min supine phase of the head-up tilt test was followed by recording 600 cardiac cycles on tilt, that is, 5-10 min. Three groups of patients were studied, each including 20 subjects matched for age and gender--healthy subjects, patients with essential hypertension (HT), and patients with chronic fatigue syndrome (CFS). The latter group was studied on account of the well-known dysautonomia of CFS patients, which served as contrast against the cardiovascular reactivity of the healthy population. A total of 52 variables of the HR and PTT were determined in each subject. The multivariate model identified the best predictors for the assessment of reactivity of healthy subjects vs CFS. Based on these predictors, the "Fractal & Recurrence Analysis-based Score" (FRAS) was calculated: FRAS=76.2+0.04*HR-supine-DET -12.9*HR-tilt-R/L -0.31*HR-tilt-s.d. -19.27*PTT-tilt-R/L -9.42*PTT-tilt-WAVE. The median values and IQR of FRAS in the groups were: healthy=-1.85 (IQR 1.89), hypertensives=+0.52 (IQR 5.78), and CFS=-24.2 (5.34) (HT vs healthy subjects: P=0.0036; HT vs CFS: P<0.0001). Since the FRAS differed significantly between the three groups, it appears likely that the FRAS may recognize phenotypes of cardiovascular reactivity.

Adult↗
PubMedDate not supplied

Statistical analysis in andrology.

The authors began a statistical study on a file group of 9384 records of semen analyses and anamnestic data (P-1). From this file, they selected a group of 5191 patients having undergone analysis at least one time (P-2) and a file of 850 patients having undergone analysis at least three times (P-3). Finally a new group, derived from P-3, of 203 patients followed by their medical team was created (P-4). Two control groups-composed of 20 sperm-bank donors (DON) and 740 prevasectomy subjects (VAS)-were also created. Frequency distributions and cluster analyses were carried out. The multivariate statistical analysis allows a distinction to be made between fertile and infertile subjects regarding a patient's clinical condition. The most discriminating parameters appear to be sperm concentration and, above all, forward motility and sperm morphology.

Adolescent↗
PubMed1996

Black race is an adverse prognostic factor for prostate cancer recurrence following radical prostatectomy in an equal access health care setting.

PURPOSE: We determined if black men with clinically localized adenocarcinoma of the prostate have the same recurrence-free outcome following radical prostatectomy, and whether they have similar preoperative, operative and pathological characteristics as white men in an equal access health care environment. MATERIALS AND METHODS: We studied consecutive single hospital case series of 366 white and 107 black patients who underwent radical prostatectomy between 1975 and February 29, 1995. Evaluation included comprehensive retrospective chart review, prospective data collection and proactive followup. Univariate and multivariate statistical analyses were done of preoperative, operative, pathological and recurrence data by race. RESULTS: Although the incidences of hypertension and diabetes, pretreatment prostate specific antigen (PSA) and serum creatinine measurements, elevated PSA as an indication for biopsy and clinical stage were greater in black men, the operative variables of blood loss, operative time and performance of a nerve sparing procedure were not different. The incidence of margin positivity was greater in black patients but pathological stage, Gleason score and seminal vesicle or nodal involvement were not different. Black race was an adverse prognostic factor for recurrence following radical prostatectomy after multivariate adjustment for pretreatment PSA and acid phosphatase, organ confinement status and tumor grade. CONCLUSIONS: The poorer recurrence-free outcome for black patients even after multivariate adjustment suggests a potentially more aggressive variant of prostate cancer in this population, the etiology of which is unknown. Race should be a stratification factor in clinical trials, especially those including radical prostatectomy and using recurrence-free outcome as an end point.

Adenocarcinoma↗
PubMed1995

DNA flow cytometry in node-positive breast cancer. Prognostic value and correlation with morphologic and clinical factors.

OBJECTIVE: To help clarify the possible usefulness of nuclear DNA content and S-phase fraction (SPF) as additional prognostic factors in node-positive breast cancer patients because there is increased interest in the development of new factors that might provide more detailed prognostic information. STUDY DESIGN: We performed a DNA and SPF analysis by flow cytometry using a multivariate statistical model on a group of 139 node-positive breast cancer patients with clearly defined inclusion and exclusion criteria. RESULTS: The percentage of aneuploidy increased with the number of involved nodes. Aneuploid tumors were more often found among grade 3 and among receptor-negative tumors. Univariate analysis showed a strong effect on recurrence-free survival (RFS) for the number of involved nodes (P < .001) and for tumor size (P = .013). Grade 3 and receptor-negative tumors showed a nonsignificant trend toward increased risk. The relative risk of aneuploid tumors was 1.19 (95% confidence interval, 0.75-1.87). Multivariate analysis revealed only the number of involved nodes to be an independent prognostic factor (P = .002); ploidy showed no effect (P = .684). SPF did not show any significant effect on RFS, even in a univariate analysis. CONCLUSION: These results suggest that nuclear DNA content and SPF correlate with morphologic factors. Their routine clinical use, however, in node-positive breast cancer patients receiving adjuvant therapy seems to have no clinical relevance and therefore can be omitted.

Aneuploidy↗
PubMed1996

Therapeutic options and results for the management of minimally invasive carcinoma of the breast: influence of axillary dissection for treatment of T1a and T1b lesions.

BACKGROUND: Axillary dissection has maintained a role of primacy for the surgical therapy of invasive carcinoma of the breast for many years. More recently, early (T1) minimally invasive carcinoma of the breast has been diagnosed with increasing frequency, and the necessity of axillary dissection for sampling purposes in these small tumors has been questioned, based primarily on the finding of low rates of axillary metastases. STUDY DESIGN: The Rhode Island State Tumor Registry records of 1,126 patients with T1a or T1b tumors were examined to assess the effect of axillary dissection on patient outcome. These data span 9 years (1985 to 1992) with a median follow-up duration of 64 months. Five-year overall, disease-free, and breast cancer-specific (determinate) survival were determined according to treatment modality. Axillary node positivity was calculated for patients with minimally invasive carcinoma of the breast who underwent axillary dissection. Multivariate statistical methods were used to provide adjustment for known confounding prognostic variables. RESULTS: Omission of axillary dissection occurred in 157 cases and correlated with reductions in overall, disease-free, and breast cancer-specific survival (p < .001 in all cases). Nodal status significantly influenced disease-free survival in minimally invasive carcinoma of the breast (90 percent node-negative compared with 76 percent node-positive, p = .02). Nodal positivity was evident in 18.2 percent of patients undergoing axillary dissection for minimally invasive carcinoma of the breast (9.8 percent for T1a, 19.4 percent for T1b, p = .01). In multivariate analysis, the performance of axillary dissection with breast conservation or modified radical mastectomy were independent predictors of overall survival, as well as disease-free and breast cancer-specific survival. CONCLUSIONS: A significant number of patients with small (less than or equal to 1 cm) invasive tumors of the breast will have axillary metastases at the time of diagnosis. Omission of axillary dissection in these patients was associated with significant impairment of overall, disease-free, and breast cancer-specific survival. Axillary dissection should continue to be a standard approach for the surgical therapy of all patients with invasive carcinoma of the breast, regardless of tumor size.

Adenocarcinoma, Mucinous↗
PubMed2006

Case-control study of the relationship between MRSA bacteremia with a vancomycin MIC of 2 microg/mL and risk factors, costs, and outcomes in inpatients undergoing hemodialysis.

BACKGROUND: An increased prevalence of bacteremia caused by methicillin-resistant Staphylococcus aureus (MRSA) with a vancomycin hydrochloride MIC of 2 microg/mL was noted in a population of inpatients undergoing hemodialysis at Baptist Memorial Health Care, Memphis, Tennessee. OBJECTIVES: The aims of this study were to determine risk factors for infection with MRSA and to assess the differences in clinical and economic outcomes in patients undergoing hemodialysis with MRSA bacteremia with vancomycin MIC 2 microg/mL versus those with MRSA bacteremia with vancomycin MIC < or =0.5 microg/mL and uninfected controls. METHODS: This retrospective case-control study was conducted at Baptist Memorial Health Care. The study population (inpatients undergoing hemodialysis for MRSA bacteremia with vancomycin MIC 2 microg/mL [high-MIC group], MIC < or = 0.5 microg/mL [low-MIC group], and uninfected controls) was identified. Risk factors and clinical and economic outcomes (costs of hospitalization, nursing, and pharmacy) were determined and compared using univariate and multivariate statistics. RESULTS: Fifty patients with MRSA bacteremia undergoing hemodialysis were identified during the study period (high-MIC group, 17 [11 women, 6 men; mean (SD) age, 60 (17) years]; low-MIC group, 33 [23 women, 10 men; mean (SD) age, 62 (14) years]) and matched with 100 uninfected controls (57 men, 43 women; mean [SD] age, 63 [15] years). Risk factors for MRSA bacteremia found to be associated with high MIC included female sex, higher body mass index (1-point increments), recent surgery, and a history of cardiovascular disease (P < 0.05, P < 0.046, P = 0.04, and P = 0.028, respectively) (multivariate analysis). In the outcomes analysis, mortality was significantly higher in the high-MIC group compared with those in the low-MIC and control groups (35% vs 24% and 15%, respectively; P = 0.022). Total mean (SD) hospitalization costs were significantly higher in the high-MIC group compared with those in the low-MIC group and controls (US $47,624 [$80,534] vs $26,792 [$25,167] and $13,185 [$15,568], respectively; P < 0.001). Nursing costs were almost 6-fold higher in both infected groups compared with those in controls. Pharmacy costs in the low- and high-MIC groups were 3- to 6-fold higher, respectively, compared with those in controls. CONCLUSIONS: Surgery within the previous 6 months and intensive care unit admission were identified as significant risk factors for patients with MRSA bacteremia with a vancomycin MIC 2 microg/mL undergoing hemodialysis. These patients experienced a longer mean hospital length of stay and increased hospital costs compared with patients with MRSA bacteremia with a vancomycin MIC < or =0.5 microg/mL and uninfected controls.

Adult↗
PubMed1996

Predictors of death in nonruptured and ruptured abdominal aortic aneurysms.

PURPOSE: This study evaluated perioperative variables to predict death in nonruptured and ruptured abdominal aortic aneurysm (AAA) surgery. METHODS: A consecutive review of all patients who underwent AAA surgery from January 1984 to December 1993 was carried out. Perioperative variables were analyzed with univariate and multivariate statistical models to predict mortality rates. RESULTS: Four hundred seventy-eight patients with nonruptured AAAs and 157 patients with ruptured AAAs were studied. In patients with nonruptured AAAs, the mortality rate was 3.8%. Using stepwise logistic regression analysis, independent predictors of death were perioperative myocardial infarction (odds ratio [OR], 5.0; p < 0.01), prolonged postoperative ventilation (OR, 4.0; p < 0.01), history of peripheral vascular disease (OR, 2.9; p < 0.01), preoperative renal dysfunction (OR, 2.7; p < 0.01), and history of congestive heart failure (OR, 2.6; p < 0.03). In patients with ruptured AAAs, the mortality rate was 46%. Analysis of preoperative variables using multivariate stepwise logistic regression found predictors of death to be preoperative unconsciousness (OR, 3.1; p < 0.01), advanced age (OR, 1.9; p < 0.01), and cardiac arrest (OR, 1.8; p < 0.05). In patients who survived the initial surgery for ruptured AAA, a second stepwise logistic regression model found independent predictors for subsequent postoperative death to be coagulation disorder (OR, 7.9; p < 0.01), ischemic colitis (OR, 6.4; p < 0.01), inotropic support beyond 48 hours (OR, 4.8; p < 0.01), delayed transport to operating room (OR, 4.6; p < 0.01), advanced age (OR, 4.4; p < 0.01), perioperative myocardial infarction (OR, 4.0; p < 0.05) and postoperative renal dysfunction (OR, 3.7; p < 0.01). CONCLUSION: Prolonged ventilation, perioperative myocardial infarction, a history of peripheral vascular disease, preoperative renal dysfunction, and a history of congestive heart failure are independent predictors of perioperative death in patients with nonruptured AAAs. For patients with ruptured AAAs, mortality rates can be estimated before surgery using age, level of consciousness, and cardiac arrest. For patients who survive the initial surgery for ruptured AAA, subsequent mortality rates can also be predicted.

Aged↗
PubMed1992

Fused eyelids in the extremely premature infant: multivariate analysis of survival and outcome.

The presence of fused eyelids at birth in the extremely low birthweight infant (less than 1000 gm) is often regarded by physicians as an indication of nonviability. This is especially true for the pediatrician who does not have routine exposure to extremely premature infants and may use the presence of fused eyelids to influence the level of resuscitation afforded the infant in the first crucial minutes following birth. Unfortunately, there are scant data in the literature to guide general pediatricians with regard to this issue. The purpose of this study was to examine, with the aid of multivariate statistical analysis, the survival and combined outcome score in extremely premature infants with and without fused eyelids. The combined outcome was a composite of several outcome variables (intraventricular hemorrhage, bronchopulmonary dysplesia, and retinopathy of prematurity); survival was defined employing the standard definition of neonatal survival, that is, alive at 28 days post natal age. Combined outcome and survival were analyzed with regard to several independent variables (birthweight, gestational age, and 5-minute Apgar scores, mode of delivery, race, sex, and maternal age). A regression analysis was performed to determine the effect of the independent variables on the combined outcome. A separate multivariate logistic regression analysis was employed to determine the effect of the same independent variables on neonatal survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗
PubMed1996

The pituitary-gonadal axis and health in elderly men: a study of men born in 1913.

The results of recent studies suggest that a relative hypogonadism in men is associated with several established risk factors for prevalent diseases. Therefore, we determined total and free testosterone, luteinizing hormone (LH), and sex-hormone binding globulin (SHBG) in a cohort of randomly selected men (n = 659) at 67 years of age. These data were analyzed cross-sectionally in relation to blood glucose and serum insulin, which were measured while fasting and after an oral glucose tolerance test, in addition to plasma lipids and blood pressure. The data were also analyzed in relation to impaired glucose tolerance (IGT) and diabetes, which were discovered at examination or earlier diagnosis. Risk factors for the development of diabetes up to 80 years of age were analyzed with univariate and multivariate statistics. Total and free testosterone and SHBG concentrations correlated negatively with glucose and insulin values; total testosterone and SHBG, with triglycerides; and SHBG, with blood pressure (from P < 0.05 to P < 0.01). Men with IGT or newly diagnosed diabetes had higher BMI values (26.2 +/- 0.31 and 27.0 +/- 0.59 [mean +/- SE], respectively) and waist circumference (99.0 +/- 1.03 and 100.5 +/- 1.57) than nondiabetic men (BMI, 25.1 +/- 0.14; waist circumference, 95.4 +/- 0.47; P < 0.05), indicating abdominal obesity. Such men and men with previously diagnosed diabetes had, in general, lower total and free testosterone and SHBG levels, while those for LH were not different. In multivariate analyses that included BMI, waist-to-hip ratio, total and free testosterone, and SHBG, the remaining independent predictors for the development of diabetes were low total testosterone (P = 0.015) and, on the borderline, low SHBG (P = 0.053). In relation to nondiabetic men, the risk ratio for mortality, myocardial infarction, and stroke increased gradually and significantly from 1.18 to 1.68, from 1.51 to 1.78, and from 1.72 to 2.46 in men with IGT, newly diagnosed diabetes, and previously known diabetes, respectively. It was concluded that low testosterone and SHBG concentrations in elderly men are associated with established risk factors for diabetes and in established diabetes. Moreover, low testosterone levels independently predict the risk of developing diabetes. In different degrees of expression, the diabetic state predicts strongly (and gradually mortality from) myocardial infarction and stroke. It has been suggested that a relative hypogonadism might be a primary event, because other studies have shown that testosterone deficiency is followed by insulin resistance, which is ameliorated by testosterone substitution. The data suggest that the relative hypogonadism involved might be of both central and peripheral origin.

Aged↗
PubMed1999

Outpatient exercise training in children with cystic fibrosis: physiological effects, perceived competence, and acceptability.

Exercise training is currently advocated as part of the treatment of patients with cystic fibrosis (CF). However, data are few that document physiologic benefits or changes in patients' perceptions of long-term training programs in children with CF. The aim of this study was to investigate the effects and acceptability of a home cycling program in children with CF. Fourteen patients (9 boys, 5 girls) with CF, mean (SD) age 14.1 (2.0) years, with mild to moderate impairment of lung function (forced expiratory volume in 1 s, mean (SD) 58.3 (16.3)% of predicted) were studied for 1 year. The first half of the study year was used to obtain baseline values at 0 and 6 months. During the second half of the year, a cycle program was carried out 5 times a week, for 20 min each day at a level of work that resulted in a heart rate of 140-160 beats/min. Once a week the cycle program was supervised by a physiotherapist. Measurements were repeated at 12 months. Effects of the exercise program were measured in terms of lung function, nutritional status, growth, muscle strength, exercise performance, perceived competence, and attitude towards the training program. Differences between the changes during the 6-month training period as compared to the 6-month control period were analyzed by multivariate statistics and nonparametric tests. Statistically significant differences (P < 0.05) between the two periods were found with respect to muscle strength of knee extensors and ankle dorsiflexors, and with respect to maximal oxygen consumption per kg body weight as well as per kg fat free mass. All changes were positive. No adverse effects were found. Perceived competence showed significant positive changes in feelings about physical appearance, general self-worth, and Total Perceived Competence Score. Scores concerning perceived acceptability of the program were significantly lower at the end of the training period; however, patients reported that they did want to continue with other sorts of training. We conclude that an exercise training program in the home can produce beneficial effects on oxygen consumption, muscle force, and perceived competence in children with CF. However, acceptability of the program was low, suggesting that long-term adherence would be poor, and hence, other sorts of training need to be identified.

Adolescent↗
PubMed1991

Multivariate analysis of cardiovascular reflexes applied to the diagnosis of autonomic neuropathy.

A battery of cardiovascular reflex tests is usually performed for the diagnosis of autonomic neuropathy. The tests discriminate well between normal and definitely abnormal autonomic function. However, in some patients the results are borderline and their autonomic status cannot be better defined. We performed multivariate statistical analysis of six cardiovascular autonomic tests with the aim of increasing their diagnostic efficiency. Eighty-five healthy subjects and 95 patients at risk for autonomic neuropathy were studied. Principal component analysis and two pattern recognition methods, the Bayesian technique and the SIMCA method, were applied. It was found that: (1) normal models obtained by Bayesian analysis showed very high specificity and sensitivity; (2) a battery of two tests for parasympathetic function (R-R interval variation test, deep breathing) and two tests for sympathetic function (blood pressure responses to standing and to sustained handgrip) provide an appropriate diagnostic approach, if multivariate analysis is used; (3) multivariate analysis allows a more precisely defined assessment of autonomic nervous system function in so-called borderline patients.

Adult↗
PubMed2003

Comparison of ultrasound and X-ray absorptiometry bone measurements in a case control study of female rheumatoid arthritis patients and randomly selected subjects in the population.

To compare quantitative ultrasound (QUS) and dual-energy X-ray absorptiometry (DXA) bone measurements in female rheumatoid arthritis (RA) patients and controls were randomly selected from the population; secondly, to examine disease and demographic factors associated with these bone measurements. In a total of 115 RA patients (mean age 63.0 years) and 115 age- and gender-matched controls demographic and clinical variables were collected and heel QUS parameters [speed of sound (SOS), broadband ultrasound attenuation (BUA) and stiffness index (SI)] as well as DXA bone mineral density (BMD) at spine and hip were measured. The differences in QUS and DXA measurements between RA patients and controls were tested both on a group and on an individual level. Univariate and multivariate statistical tests were applied to explore for associations to the bone measurements. In the RA patients mean disease duration was 16.6 years, erythrocyte sedimentation rate 23.6 mm/h, M-HAQ 1.68, 28-swollen joint count 7.7, 18-deformed joint count 4.5, 50.0% were rheumatoid factor (RF) positive and 44.2% were current users of prednisolone. All bone measurements were reduced in RA patients compared with controls (SOS 1.9%, BUA 9.4%, SI 19.5%, femoral neck BMD 7.4%, total hip BMD 7.5%, spine L2-L4 BMD -3.0%). Only at spine was the BMD reduction not statistically significant ( P=0.21). In the subgroup of never users of prednisolone SOS was decreased by 1.4%, BUA by 3.7%, SI by 11.0, femoral neck BMD by 2.7%, and total hip BMD by 0.6%, whereas for spine L2-L4 BMD was increased by 4.3% and only for SOS and SI was the decrease statistically significant. The QUS discriminated better than DXA between patients and controls on a group level, but this difference in favor of QUS disappeared on an individual level when the measurement errors were taken into account. Age, BMI, RF and deformed joint count, but not corticosteroids, were independently associated with at least one of the QUS and one of the DXA measures; however, the association between disease-related variables was stronger with the QUS bone measures than with the DXA bone measures. The results for the quantitative QUS bone measures seem to mainly reflect bone mass. Disease-related variables in multivariate analysis remained independently associated with all QUS measures even when adjusting for DXA bone measures. Further studies are needed to examine if QUS may reflect other aspects than bone mass and be a potential better predictor for fracture risk in RA and corticosteroid-induced osteoporosis.

Absorptiometry, Photon↗
PubMed1996

Predictive value of EEG for outcome and epilepsy following neonatal seizures.

The value of the electroencephalogram in predicting outcome and epilepsy was examined in neonates who had experienced EEG-confirmed neonatal seizures. Electroencephalogram, neuroimaging studies, and other clinical variables were systematically analyzed in 81 consecutive neonates with EEG-confirmed seizures. The surviving subjects were followed for a mean of 17 months to determine if they developed post-neonatal seizures (PNS) and abnormal neurodevelopmental outcome. Several EEG variables were correlated with neurodevelopmental outcome and PNS when analyzed with univariate and multivariate statistical analyses. The EEG background activity and the presence of status epilepticus were strong predictors of outcome, but were not associated with PNS. The presence of rhythmic theta-alpha bursts was highly favorable for both outcome and PNS. In the interictal EEG, the number of negative sharp waves in the temporal region correlated with outcome and PNS. Clinical variables associated with unfavorable outcomes included an abnormal neonatal neurologic exam and certain seizure etiologies (e.g. cerebral dysgenesis and infections). Global abnormalities on neuroimaging studies were invariably associated with an unfavorable outcome and with the development of PNS in 66% of cases. Using multivariate analysis, prediction of outcome (favorable versus unfavorable) was accurately achieved in 85% of cases when combining EEG variables with neuroimaging and clinical findings. In conclusion, in neonates with EEG-confirmed seizures, the EEG is a useful predictor of outcome, but is a less useful predictor of PNS.

Analysis of Variance↗
PubMed2004

Association of infratentorial brain arteriovenous malformations with hemorrhage at initial presentation.

BACKGROUND AND PURPOSE: The goal of this study was to analyze the association of hemorrhagic presentation with infratentorial brain arteriovenous malformations (AVMs). METHODS: The 623 consecutive, prospectively enrolled patients from the Columbia AVM Databank were analyzed in a cross-sectional study. Clinical presentation (diagnostic event) was categorized as intracranial hemorrhage or nonhemorrhagic presentation. From brain imaging and cerebral angiography, AVM location was classified as either infratentorial or supratentorial. Univariate and multivariate statistical models were applied to test the effect of age, sex, AVM size and location, venous drainage pattern, and associated (ie, feeding artery or intranidal) arterial aneurysms on the likelihood of hemorrhage at initial AVM presentation. RESULTS: Of the 623 patients, 72 (12%) had an infratentorial and 551 (88%) had a supratentorial AVM. Intracranial hemorrhage was the presenting symptom in 283 patients (45%), and infratentorial AVM location was significantly more frequent (18%) among patients who bled initially (6%; odds ratio [OR], 3.60; 95% confidence interval [CI], 2.09 to 6.20). This difference remained significant (OR, 1.99; 95% CI, 1.07 to 3.69) in the multivariate logistic regression model controlling for age, sex, AVM size, deep venous drainage, and associated arterial aneurysms. In the same model, the effect of other established determinants for AVM hemorrhage--ie, AVM size (in 1-mm increments; OR, 0.95; 95% CI, 0.94 to 0.96), deep venous drainage (OR, 3.09; 95% CI, 1.87 to 5.12), and associated aneurysms (OR, 2.78; 95% CI, 1.76 to 4.40)--remained significant. CONCLUSIONS: Our findings suggest that infratentorial AVM location is independently associated with hemorrhagic AVM presentation.

Adult↗
PubMed2005

A quality framework for addiction treatment programs.

AIM: To identify and specify the structure and the elements of a quality framework for addiction treatment programs. METHOD: Concept mapping strategy was applied. In brainstorm sessions, 70 statements were generated and rated by 90 representatives of three stakeholder groups. Using multivariate statistical analyses, the statements were positioned on a map. RESULTS: Two dimensions 'Best Practice' and 'Performance' and nine clusters were identified. The three most important clusters were 'Attitude of staff', 'Client orientation' and 'Treatment practice'. The most important statement was effectiveness. CONCLUSION: The specific quality framework identified has some similarity with existing non-specific frameworks.

Benchmarking↗
PubMed1995

Asthma and bronchial reactivity: a contribution from multivariate analysis.

This study was performed on 508 young male candidates on the military pilot course of the Air Force Academy. Observations of the following parameters were made: immunoglobulin E (IgE) level, skin sensitivity test (prick test) to most common continuous and seasonal allergens, and results of nonspecific bronchial provocation tests with methacholine. The analysis strategy that has been developed consists of two techniques, "multiple correspondence analysis (MCA)" and "automatic classification". The correlation between the categories of the characters evaluated are: degree of high skin reactivity in relation to high IgE levels, hyperreactivity to low methacholine dose (noticed mainly in subjects allergic to continuous antigens), low degree of skin reactivity (both to continuous and seasonal antigens and found in relation to a low methacholine dose) and medium and low IgE levels. The cluster analysis defined three different classes of subjects: 1) 51.97% of the total observed subjects. 68.82% of those subjects that showed IgE levels above 7300 and a high reactivity to low methacholine dose; 2) 15.94% of subjects with a severe allergy to pollens; and 3) 32.09% of subjects with IgE levels lower than 900, low bronchial reactivity and no allergic component for either seasonal or continuous antigens. The use of multivariate statistical techniques in this field of pathophysiology has allowed a confirmative-explorative study of allergic phenomena in relation to several characters, and the determination of classes of subjects characterized by well-defined categories.

Adolescent↗