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PubMed1995

Evaluation of GM-CSF mouthwash for prevention of chemotherapy-induced mucositis: a randomized, double-blind, dose-ranging study.

Uncontrolled clinical trials have shown that parenteral administration of GM-CSF reduces the frequency of chemotherapy-induced mucositis. The mechanism of this effect could be related to acceleration of haematopoiesis and/or increase in functional activation of WBC. We conducted a double-blind, placebo-controlled, dose ranging study of GM-CSF (mol-gramostim) mouthwash in patients with breast cancer during the first treatment cycle of a combination chemotherapy regimen which has historically produced dose-limiting (grade > or = 3) mucositis in approximately 39% of patients. Subjects were randomized to receive either placebo mouthwash (0.1 percent albumin) or one of four concentrations of GM-CSF mouthwash (0.01, 0.1, 1.0 or 10 mcg/ml). The primary endpoint was to evaluate the relationship between dose of GM-CSF mouthwash received and probability of grade > or = 3 mucositis using a logistic model. Solutions were administered four times daily starting within 24 hours of chemotherapy initiation and continuing until the end of the cycle (day 21). Mucositis was assessed on days 1-6, 10, 15 and 21. Day 6 plasma samples were assayed for GM-CSF. Forty-five patients were evaluable for response (nine per dosing group). A 42% risk (15/36) of mucositis grade > or = 3 was evident on day 15 in patients receiving GM-CSF compared to 2 of 9 patients on the placebo arm. No evidence of dose response was found by logistic regression. Five patients had a detectable plasma concentration of GM-CSF (56-209 pg/ml). A positive correlation between GM-CSF dose and leukocyte recovery was noted (P = 0.04).

Adult↗

PubMed2002

Hypertension in Oman: distribution and correlates.

BACKGROUND: International studies have reported increased prevalence of hypertension and other cardiovascular risk factors, Our aim was to study the distribution and the correlates of hypertension (HTN - systolic or diastolic) in a community based survey (National Health Survey, 2000). METHODS: A cross-sectional survey of the health status of Omani community was designed. Face to face interview including demographic data, blood pressure measurement, fasting blood glucose and serum cholesterol, weight, height, waist and hip measurement for 7011 Omani subjects with a response rate ranging between about 83% (for fasting blood glucose) to about 91% (for blood pressure measurement). RESULTS: The crude prevalence of HTN was 33.1%, while the age-adjusted prevalence was 38.3%. Older age groups, male gender, lower level of education, non- working, hypercholestremia, being married, obese, smoker, or having abnormal Waist Hip Ratio (WHR), or Total Impaired fasting glucose (TIFG) were found to be associated with hypertension in bivariate analysis. Logistic models were run to identify the adjusted Odds Ratio for the overall sample, for separate genders and age groups. For the overall sample, subjects aged 60 and above were 5.4 times more likely to be hypertensive than those below forty. Female gender was a protective factor in the overall sample, while it increased the risk by 1.4 times among those aged 60+. Obese or centrally obese subjects were also more likely to be hypertensive. Subjects with impaired fasting glucose, diabetes, or hyperchlosteremia were more likely to have hypertension than others in the majority of the logistic regression models. CONCLUSION: Hypertension is considered a major public health problem in Oman. Increasing the awareness of both health care providers and the community is crucial.

Adult↗

PubMed1996

Risk factors for neonatal sepsis.

OBJECTIVE: To determine the associations between maternal characteristics, intrapartum events, and neonatal sepsis by multivariate analysis. METHODS: We enrolled 823 women from a high-risk population and analyzed maternal and neonatal demographic and outcome variables with univariate analysis and multivariate logistic modeling. RESULTS: Two-hundred sixteen women (26%) were colonized with group B streptococci, 82 (10%) developed chorioamnionitis, and 141 (17%) delivered prematurely. Culture-proven neonatal sepsis or meningitis was found in 15 of 833 (1.8%) neonates, and 101 of the remaining 818 (12.3%) infants were suspected to have sepsis or pneumonia. Multivariate analysis of risk factors for proven neonatal sepsis demonstrated a statistically significant association with decreasing gestational age, duration of internal monitoring for more than 12 hours (odds ratio [OR] 7.2, 95% confidence interval [CI] 1.6-32.2), maternal group B streptococcal infection (OR 4.2, 95% CI 1.4-13.1), chorioamnionitis (OR 4.4, 95% CI 1.2-16.1), and endometritis (OR 6.4, 95% CI 1.2-34.2). CONCLUSION: Through the use of multivariate modeling, we determined that chorioamnionitis or endometritis, preterm delivery, group B streptococcal colonization, and a prolonged duration of internal monitoring are independent risk factors for neonatal sepsis. We postulate that the presence of a foreign body that traverses the birth canal may facilitate ascending peripartal infection.

Confidence Intervals↗

PubMed1995

Interpretation of diagnostic implications of fluorescence parameters for atherosclerosis in fibrous, calcified and normal arteries.

Fluorescence spectroscopy presents great interest for the diagnosis of atherosclerosis. Nevertheless there are some difficulties in the interpretation of diagnostic information. This could be overcome by precise methods of extraction of the diagnostic parameters and convenient statistical analysis, which are the subject of this work. Fluorescence excitation-emission matrices from different categories of coronary arteries were developed and used to derive the optimum excitation wavelength on the one hand and to assign the spectra to specific chromophores on the other hand. Simple dimensionless functions (Fi) were formed by the ratio of the intensities at selected wavelength and the logistic model was used for statistical analysis. Decision surfaces were drawn and it was estimated that the probability of correct classification is 88%. The algorithm correctly diagnoses 97% of healthy from diseased samples and 80% of fibrous from calcified coronary arteries.

Algorithms↗

PubMed2003

Off-pump coronary artery bypass surgery does not reduce gastrointestinal complications.

OBJECTIVES: Gastrointestinal (GI) complications following on-pump coronary artery bypass grafting (CABG) are rare, but carry a high mortality rate. Prolonged cardiopulmonary bypass (CPB) has been associated with a higher incidence of such complications. Little is known about the effect of avoiding CPB on GI complications. Our hypothesis was that off-pump CABG might reduce such complications. METHODS: A total of 2327 consecutive cases undergoing isolated CABG between April 1997 and May 2001 were identified from four consultants' practice at the two cardiothoracic centres involved in this study. We performed a multivariable logistic regression analysis to identify the risk factors for development of post-operative GI complications. Potential risk factors considered in the logistic model were age, sex, angina, ejection fraction, peripheral vascular disease, renal dysfunction, redo operations, previous GI complications, priority of surgery and the use of CPB. RESULTS: A total of 1210 cases were performed on CPB, compared to 1117 off-pump. The incidence of GI complications was 1.2% (n = 14) in the on-pump group and 1.6% (n = 18) in the off-pump group (P = 0.347). The incidence of in-hospital mortality, in the patients who had a GI complication, was 28.6% (n = 4) and 22.2% (n = 4), respectively (P = 0.681). The results of the logistic regression analysis showed that renal dysfunction, advancing age and previous history of GI surgery are significant risk factors for GI complications after coronary bypass surgery whether CPB is used or not. CONCLUSIONS: Our study suggests that off-pump and on-pump techniques are similar in the rates of GI complications. We suggest that a properly designed randomized control trial is needed to verify our findings.

Age Factors↗

PubMed2003

Helicobacter pylori infection in subjects with acute ischaemic stroke.

AIMS: To determine whether infection with Helicobacter pylori is a significant risk factor for stroke. SUBJECTS: A total 467 in-patients with clinical evidence of acute ischaemic stroke and 388 healthy controls with no evidence of cerebrovascular disease. METHODS: This was a case control study. The prevalence of Helicobacter pylori was measured by enzyme-linked immunosorbent assay in stroke patients and controls. A positive titre was defined as >15 U/ml and relationship with circulating plasma fibrinogen and social depravation was expressed using the Townsend Index. RESULTS: There were significantly more Helicobacter pylori positive individuals (274/398 (69%)) in the cases compared to the controls (206/352 (58.5%)). Fibrinogen levels were also significantly higher in Helicobacter pylori positive (mean 4.14, standard deviation 1.33) than negative individuals (mean 3.78, standard deviation 1.28). The association between Helicobacter pylori and stroke was lost in a logistic model controlling for socio-economic status. Furthermore, fibrinogen levels were not associated with Helicobacter pylori status in a linear regression model controlling for socio-economic status. CONCLUSIONS: Infection with Helicobacter pylori is associated with an increased risk of stroke and increased fibrinogen levels but these findings can be attributed to a confounding effect of socio-economic status.

Aged↗

PubMed1999

Effectiveness of BCG vaccination against tuberculous meningitis.

OBJECTIVE: To assess the protective effectiveness of BCG vaccination against tuberculous meningitis, while controlling for age, nutrition and socio-economic status, in children 1 month to 12 years of age. DESIGN: Case-control study. SETTING: Secondary care referral and teaching hospital. METHODS: Cases were those conforming to the definition of tuberculous meningitis and controls were patients admitted after every third consecutive case included in the study from September 1995 till the end of August 1997 and who did not suffer from any central nervous system disorder. RESULTS: Among the 192 cases and 70 controls, BCG scar was present in 57.8% and 75.7%, respectively. The crude odd's ratio (OR)for tuberculosis meningitis with a BCG scar was 0.44 (95% CI, .24-0.81; p = 0.008), while the adjusted OR was 0.53 (95% CI, 0.26-1.06; p value = 0.07) after controlling for weight, age, sex and place of residence. Higher weight for age and urban residence were associated with a decreased risk of tuberculous meningitis in the logistic model. CONCLUSIONS: BCG vaccination offers protection against tuberculous meningitis. Since improvement in weight for age was associated with a decreased risk of disease, further studies are needed to evaluate the association, if any, between nutritional status and vaccine efficacy.

Age Distribution↗

PubMed1997

Coroner-reviewed infant and toddler deaths. Many "undetermineds" resemble homicides.

Although homicide is a leading cause of death of infants and toddlers, there is some suspicion that an unknown number of additional deaths are unrecognized homicides. The authors used California mortality data from 1969 to 1991 to examine 12,246 injury deaths that occurred before age 5. Characteristics of the dead child, injury event, and postmortem were compared for accidents, homicides, and undetermined deaths. A logistic model was developed to differentiate homicides from accidental deaths and then was used to predict whether undetermined deaths were likely to be homicides or accidents. Unlike accidental deaths, undetermineds and homicides had similar distribution patterns of age, race, sex, and place of injury. The predictive model indicates that 43.8% of the undetermined injury deaths were similar to homicides on several characteristics. True rates of homicide for infants and toddlers may, unfortunately, be nearly one fifth and one tenth higher, respectively, if the undetermined deaths that resemble homicides are taken into account.

Accidents↗

PubMed2000

Probability of helicobacter pylori infection based on IgG levels and other covariates using a mixture model.

BACKGROUND: To use IgG antibody measurements to detect infection with Helicobacter pylori (H. pylori). one typically defines a cut-off value based on samples of persons presumed to be infected or uninfected. When there are no good 'gold standard' tests to determine infection status, or when laboratory conditions vary, it is useful to have a method based on the IgG measurements themselves to determine infection status. METHODS: We present a two component mixture model to analyse serologic data on H. pylori infection. The mixing proportions correspond to the probability that a latent variable, the true, unknown infection status I of a person, is either 0 (uninfected) or 1 (infected). By using a logistic model for these probabilities, we are able to incorporate covariate information. RESULTS: The model is applied to IgG data from Shandong, China. The distribution of the true infection status given the IgG value and a set of covariates is calculated using the IgG distribution function. An optimal cut-off point is found by minimising the probability of misclassification for the Shandong data. The optimal cut-off point is slightly lower than the pre-defined one. CONCLUSIONS: We contrast results from the mixture model with results from tabulations and from standard logistic regression that are based on fixed cut-points. The mixture model yields information on the probability that a person is truly infected as a function of IgG levels and covariates. In our data, the mixture model indicates that a slightly lower cut-off value than the pre-defined cut-point 1.0 can reduce misclassification rates.

Adult↗

PubMed1998

The effect of a badger removal programme on the incidence of tuberculosis in an Irish cattle population.

The risk of a confirmed tuberculous herd restriction was examined using a logistic model for herds involved in the East Offaly Badger Research Project, Ireland, from 1988-1995. Cattle herds present in the badger-removal area had a significantly lower proportion of new confirmed tuberculous herd restrictions compared with cattle from an area where no systematic badger removal was attempted.

Animals↗

PubMed2005

Falls in hemodialysis patients: prospective study of incidence, risk factors, and complications.

BACKGROUND: Falls are common in elderly nonuremic patients and are associated with poor outcomes. Recent international guidelines recommend proper assessment of fallers and those at risk for falling to implement multidimensional preventative strategies. Surprisingly, the incidence, risk factors, and complications of falls in hemodialysis (HD) patients are unknown despite the growing number of elderly patients on HD therapy worldwide. METHODS: We contacted all patients from 7 Belgian in-center HD units. Consenting patients were evaluated in March 2001 for the presence of risk factors for falling (demographics, selected comorbid conditions, gait/balance tests, main biochemical markers, and drug and HD regimens). Falls (including circumstances and derived complications) subsequently were recorded by staff members of all 7 units for 8 weeks from April 1, 2001, through questioning of patients, relatives, and caregivers. Fractures consecutive to falls were recorded for 12 months. RESULTS: Three-hundred eight patients agreed to participate (acceptance rate, 94%). They had a median age of 70.9 years (56% men, 27% patients with diabetes). Thirty-nine patients (12.7%) with a median age of 74.7 years fell at least once during the 8 weeks (total, 56 falls), an average incidence of 1.18 fall/patient-year. One third of the falls caused lesions requiring health care or even hospitalization (n = 6). During 12 months, 12 patients (3.9%) experienced a fall-related fracture. Logistic regression identified older age (odds ratio, 1.057/y; P = 0.01), diabetes (odds ratio, 2.747; P = 0.02), high number of prescribed oral drugs (odds ratio, 1.19/drug; P = 0.011), antidepressant use (odds ratio, 5.263; P < 0.001), and failing to walk 10 m without help (odds ratio, 2.057; P = 0.001) as independent risk factors for falling. CONCLUSION: Falls are common in in-center HD patients. The high-risk population delineated by our logistic model appears as a priority target for intervention studies (including exercise programs and more selective prescription of some drugs in particular) to reduce the incidence and complications of falls.

Accidental Falls↗

PubMed2001

Prevalence of emphysema in individuals who underwent screening CT for lung cancer in Nagano prefecture of Japan.

BACKGROUND: Screening for lung cancer with low-dose spiral computed tomography (CT) was carried out in Nagano prefecture in Japan. OBJECTIVE: To study the prevalence of emphysema in 7,847 individuals based on the Nagano spiral CT screening and to correlate the prevalence and severity of emphysema with various factors. METHODS: Spiral CT images with scan parameters of 120 kV, 50 mA, 10-mm collimation and a pitch of 2 obtained at full inspiration were retrospectively evaluated in 7,847 individuals. Emphysema was defined as the presence of low-attenuation areas in the lung parenchyma. Extent of emphysema was graded on a four-level scale and correlated with gender, age and smoking habits. RESULTS: There were 4,288 males and 3,559 females. Mean age of the subjects was 61 years; 45.8% of the participants were smokers. Overall prevalence of emphysema was 2.9%; the prevalence was significantly higher in males (5.0%) than in females (0.5%); it was also significantly higher in smokers, and increased with age. Emphysema was positively correlated with age, but there was no correlation with smoking indices. Emphysema was mostly mild and localized in the upper lung. The logistic model revealed that gender, age and smoking indices were significant factors for developing emphysema. CONCLUSIONS: Overall prevalence of emphysema was 2.9%. The prevalence was higher in males and in older people. Smoking was also related to a higher prevalence of emphysema but not to its severity.

Adult↗

PubMed1999

Human sex ratio at birth and mother's birth season: multivariate analysis.

We used a population-based historical French Canadian database to examine the effects of mother's birth season on sex ratio at birth. Non-first births in the database (n = 127,658) were analyzed for their sex, parish size (2 large parishes of Montreal and Quebec or the other smaller parishes), time period (births up to 1719 or those from 1720), maternal age (< or = 24, 25-29, 30-34, 35+ years), sex of the preceding sibling (male or female), and birth seasons of the child and his or her parents (February-April, May-July, August-October, November-January). Season of child's birth significantly affected the sex ratio (chi 2 = 11.507, d.f. = 3, p = 0.009), with the births in February-April or May-July showing a lower sex ratio. Season of mother's birth also contributed highly significantly to the variation of sex ratio (chi 2 = 15.196, d.f. = 3, p = 0.002); mothers born in February-April had a low sex ratio among their children (sex ratio = 1.013). In contrast, season of father's birth did not affect the sex ratio (chi 2 = 0.618, d.f. = 3, p = 0.892). When a multiple logistic model was applied to the data, mother's birth season was the single most significant factor. The lower sex ratio from mothers born in February-April was observed consistently for every maternal age and delivery season. Seasonal influences on female fetuses seem to have changed their future reproductive characteristics.

Canada↗

PubMed1991

Extensions to methods of sib-pair linkage analyses.

Sib-pair methods provide simple, robust, easily implemented ways to screen for linkage between a marker locus and a suspected disease susceptibility locus. The basic analysis reflects the idea that, in the presence of linkage, siblings who share more alleles at the marker locus should also tend to be concordant for disease. Available sib-pair methods do not lead directly to estimates of risk associated with nongenetic factors, may not account for a variable age-at-onset, or may require that the age-at-onset distribution be known. In this paper, we propose a method for sib-pair linkage analyses that allows for a variable age-at-onset using a logistic model, easily allows modelling of nongenetic factors, reflects the correlation of sibs within a sibship, and allows for nonzero risk in those without the susceptibility genotype. Based on a limited number of simulations, the method has as good or better power than another recently described method that also allows for a variable age-at-onset.

Epidemiologic Methods↗

PubMedDate not supplied

Epidemiology of human toxocariasis in La Réunion.

In La Réunion island (Indian Ocean) a seroepidemiological survey for toxocariasis was carried out among 387 subjects over 15 years old by Western blotting using Toxocara canis excretory-secretory larval antigens; 92.8% of the sera were positive. Statistical study, including logistic regression analysis, showed a significant correlation of Western blot results with sex, age, and absence of water supply. The final logistic model demonstrated that only the last 2 factors were significant multiplicative risk factors for toxocariasis. Sex was an independent risk factor. With this level of infection, we suggest that further surveys of ocular toxocariasis in children and teenagers of La Réunion would be advisable.

Adolescent↗

PubMed2005

TESS-based dose-response using pediatric clonidine exposures.

OBJECTIVE: The toxic and lethal doses of clonidine in children are unclear. This study was designed to determine whether data from the American Association of Poison Control Centers Toxic Exposure Surveillance System (TESS) could be utilized to determine a dose-response relationship for pediatric clonidine exposure. METHODS: 3,458 single-substance clonidine exposures in children <6 years of age reported to TESS from January 2000 through December 2003 were examined. Dose ingested, age, and medical outcome were available for 1550 cases. Respiratory arrest cases (n = 8) were classified as the most severe of the medical outcome categories (Arrest, Major, Moderate, Mild, and No effect). Exposures reported as a "taste or lick" (n = 51) were included as a dose of 1/10 of the dosage form involved. Dose ranged from 0.4 to 1980 (median 13) microg/kg. Weight was imputed based on a quadratic estimate of weight for age. Dose certainty was coded as exact (26% of cases) or not exact (74%). Medical outcome (response) was examined via logistic regression using SAS JMP (release 5.1). RESULTS: The logistic model describing medical outcome (P < 0.0001) included Log dose/kg (P = 0.0000) and Certainty (P = 0.045). CONCLUSION: TESS data can provide the basis for a statistically sound description of dose-response for pediatric clonidine poisoning exposures.

Accidents↗

PubMed1995

Criteria for safe hepatic resection.

BACKGROUND: To lower morbidity after hepatic resection, the authors examined the influence of predictor variables including: age, sex, preoperative risk factors, serum total bilirubin level, plasma retention rate of indocyanine green at 15 minutes, underlying liver disease, operative blood loss, operation time, amount of whole blood transfused, vascular occlusion time, surgical procedure employed, and extent of hepatic resection. PATIENTS AND METHODS: Between January 1990 and December 1992, 172 patients underwent hepatic resection based on our own criteria for hepatectomy, including the presence or absence of ascites, serum total bilirubin level, and the plasma retention rate of indocyanine green at 15 minutes in patients with chronic liver disease. The morbidity rate was 37.2%, and the hospital and operative mortality rates were 2.3% and 0.6%. RESULTS: The multiple logistic model revealed that the risk of morbidity was increased by longer operation time, major hepatic resection, and preoperative cardiovascular disease. CONCLUSIONS: Shortening the operation time without increasing operative blood loss and further modalities for making major hepatectomy safer are future problems to be addressed.

Adult↗

PubMed1993

Post-traumatic stress disorder in adolescents after a hurricane.

A school-based study conducted in 1990, 1 year after Hurricane Hugo, investigated the frequency and correlates of post-traumatic stress disorder (PTSD) in 1,264 adolescents aged 11-17 years residing in selected South Carolina communities. Data were collected via a 174-item self-administered questionnaire that included a PTSD symptom scale. A computer algorithm that applied decision rules of the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised to the symptoms reported was used to assign a diagnosis of PTSD and to designate the number of individuals who met the reexperiencing (20%), avoidance (9%), and arousal (18%) criteria. Rates of PTSD were lowest in black males (1.5%) and higher, but similar, in the remaining groups (3.8-6.2%). Results from a multivariable logistic model indicated that exposure to the hurricane (odds ratio (OR) = 1.26, 95% confidence interval 1.13-1.41), experiencing other violent traumatic events (OR = 2.46, 95% confidence interval 1.75-3.44), being white (OR = 2.03, 95% confidence interval 1.12-3.69) and being female (OR = 2.17, 95% confidence interval 1.15-4.10) were significant correlates of PTSD.

Adolescent↗