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EPA PMF version 5.0 and the underlying multilinear engine executable ME-2 contain three methods for estimating uncertainty in factor analytic models: classical bootstrap (BS), displacement of factor elements (DISP), and bootstrap enhanced by displacement of factor elements (BS-DISP). The goal of these methods is to capture the uncertainty of PMF analyses due to random errors and rotational ambiguity. It is shown that the three methods complement each other: depending on characteristics of the data set, one method may provide better results than the other two. Results are presented using synthetic data sets, including interpretation of diagnostics, and recommendations are given for parameters to report when documenting uncertainty estimates from EPA PMF or ME-2 applications. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate whether higher levels of urate, an antioxidant linked to a lower likelihood of developing Parkinson's disease, is also a predictor of having a dopamine transporter brain scan without evidence of dopaminergic deficit. In a cross-sectional study of 797 mildly affected, untreated parkinsonian subjects diagnosed with early Parkinson's disease in the Parkinson Research Examination of CEP-1347 Trial, we investigated the relationship at baseline between serum urate and striatal dopamine transporter density, determined by single-photon emission computed tomography of iodine-123-labeled 2-β-carboxymethoxy-3-β-(4-iodophenyl)tropane uptake. A scan without evidence of dopaminergic deficit was defined as lowest putamen iodine-123-labeled 2-β-carboxymethoxy-3-β-(4-iodophenyl)tropane > 80% age-expected putamen dopamine transporter density. The odds of having a scan without evidence of dopaminergic deficit rose across increasing quintiles of urate level, with an age- and sex-adjusted odds ratio of 3.2 comparing the highest to the lowest urate quintile (95% confidence interval, 1.5-7.2; P for trend = .0003), and remained significant after adjusting for potential confounding factors. The association was significant in men but not women, regardless of whether common or sex-specific quintiles of urate were used. Higher levels of urate were associated with a greater likelihood of a scan without evidence of dopaminergic deficit among subjects with early untreated parkinsonism in the Parkinson Research Examination of CEP-1347 Trial. The findings support the diagnostic utility of urate in combination with other determinants. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sociological studies have shown that poor social integration confers suicide risk. It is not known whether poor integration amplifies risk after adjusting statistically for the effects of mental disorders and employment status. METHOD: A case-control design was used to compare 86 suicides and 86 living controls 50 years of age and older, matched on age, gender, race, and county of residence. Structured interviews were conducted with proxy respondents for suicides and controls. Social integration was defined in reference to two broad levels of analysis: family (e.g. sibship status, childrearing status) and social/ community (e.g. social interaction, religious participation, community involvement). RESULTS: Bivariate analyses showed that suicides were less likely to be married, have children, or live with family. They were less likely to engage in religious practice or community activities and they had lower levels of social interaction. A trimmed logistic regression model showed that marital status, social interaction and religious involvement were all associated with suicide even after statistical adjusting for the effects of affective disorder and employment status. Adding substance abuse to the model eliminated the effects of religious involvement. CONCLUSIONS: The association between family and social/community indicators of poor social integration and suicide is robust and largely independent of the presence of mental disorders. Findings could be used to enhance screening instruments and identify problem behaviors, such as low levels of social interaction, which could be targeted for intervention. [ABSTRACT FROM AUTHOR]

Background. Sociological studies have shown that poor social integration confers suicide risk. It is not known whether poor integration amplifies risk after adjusting statistically for the effects of mental disorders and employment status. Method. A case-control design was used to compare 86 suicides and 86 living controls 50 years of age and older, matched on age, gender, race, and county of residence. Structured interviews were conducted with proxy respondents for suicides and controls. Social integration was defined in reference to two broad levels of analysis: family (e.g. sibship status, childrearing status) and social/community (e.g. social interaction, religious participation, community involvement). Results. Bivariate analyses showed that suicides were less likely to be married, have children, or live with family. They were less likely to engage in religious practice or community activities and they had lower levels of social interaction. A trimmed logistic regression model showed that marital status, social interaction and religious involvement were all associated with suicide even after statistical adjusting for the effects of affective disorder and employment status. Adding substance abuse to the model eliminated the effects of religious involvement. Conclusions. The association between family and social/community indicators of poor social integration and suicide is robust and largely independent of the presence of mental disorders. Findings could be used to enhance screening instruments and identify problem behaviors, such as low levels of social interaction, which could be targeted for intervention. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mental disorders amplify suicide risk across the lifecourse, but most people with mental disorder do not take their own lives. Few controlled studies have examined the contribution of stressors to suicide risk. METHOD: A case-control design was used to compare 86 suicides and 86 controls aged 50 years and older, matched on age, gender, race and county of residence. Structured interviews were conducted with proxy respondents for suicides and controls. RESULTS: Perceived physical illness, family discord and employment change amplified suicide risk after controlling for sociodemographic covariates and mental disorders that developed > or = 1 year prior to death/interview. Only the effect of physical illness (OR 6.24, 95% CI 1.28-51.284) persisted after controlling for all active mental disorders. CONCLUSIONS: Interventions to decrease the likelihood of financial stress and to help families manage discord and severe physical illness may effectively reduce suicides among middle-aged and older adults. [ABSTRACT FROM AUTHOR]

Seventy consecutive patients with refractory or relapsed Hodgkin’s disease who received high-dose chemotherapy followed by autologous stem cell rescue were analyzed to identify clinically relevant predictors of long-term event-free survival. High-dose therapy consisted primarily of carmustine (BCNU), etoposide, cytarabine and cyclophosphamide (BEAC). The 5-year Kaplan–Meier event-free survival (EFS) for the entire cohort was 32% (95% confidence interval; 18–45%) with a median follow-up of 3.6 years (range 7 months–7.6 years). The most significant predictor of improved survival was the presence of minimal disease (defined as all areas 2 cm) at the time of transplant: the 5 years EFS was 46 vs 10% for patients with bulky disease (P = 0.0002). Other independent predictors identified by step-wise regression analysis included the presence of non-refractory disease and the administration of post-transplant involved-field radiotherapy (XRT). Treatment-related mortality occurred in 13 of 70 patients: nine patients (13%) died within the first 100 days, mainly from cardiopulmonary toxicity. However, only one of 24 patients (4%) transplanted during the last 4.5 years died from early treatment-related complications. While high-dose therapy followed by autotransplantation led to long-term EFS of 50% for patients with favorable prognostic factors, a substantial proportion of patients relapsed, indicating that new therapeutic strategies are needed. [ABSTRACT FROM AUTHOR]

One hundred and thirty-six patients autografted for relapsed or refractory non-Hodgkin’s lymphoma (NHL) were evaluated to assess long-term event-free survival and to identify important prognostic factors. High-dose therapy consisted primarily of carmustine (BCNU), etoposide, cytarabine, and cyclophosphamide (BEAC) followed by unpurged autologous stem cell rescue. The 5-year Kaplan–Meier event-free survival (EFS) for the entire cohort was 34% (95% confidence interval: 24–44%) with a median follow-up of approximately 3 years (range 0–7.5 years). For patients entering with minimal disease (defined as all areas 2 cm), the 5-year EFS was 40 vs 26% for those entering with bulky disease (P = 0.0004). In the multivariate analysis, minimal disease on entry and administration of involved-field XRT post-transplant were significantly associated with improved EFS; the latter association was observed mainly in the cohort of patients with bulky disease. The overall 100-day treatment-related mortality rate was 4.4% (3% for the last 71 patients). New strategies are needed to reduce the high rate of relapse (50–60%) following autotransplantation for relapsed or refractory NHL. [ABSTRACT FROM AUTHOR]

A clinical trial efficacy analysis based on actual drug usage is described. The influence of diltiazem therapy on modality and reinfarction in the multicenter diltiazem post-infarction trial (MDPIT) is analyzed using records for drug discontinuation and reinitiation; the results are then compared with the previously published "intention to treat" analysis. As expected, previously reported beneficial effects of diltiazem therapy in patients without pulmonary congestion and previously reported harmful effects in patients with pulmonary congestion are strengthened for patients while on study medication; both effects are weakened for those not on study medication. It is also shown that for patients assigned to placebo, being on or off study medication is a powerful prognostic indicator of subsequent outcome events, especially among patients with pulmonary congestion. Analysis of discontinuation rates suggested that patients assigned to diltiazem therapy were likely to discontinue trial medication earlier than Were patients assigned to placebo, especially for those patients with pulmonary congestion. [ABSTRACT FROM AUTHOR]

OBJECTIVES: This study assessed the relationship between lead-contaminated house dust and urban children's blood lead levels. METHODS: A random-sample survey was used to identify and enroll 205 children, 12 to 31 months of age, who had resided in the same house since at least 6 months of age. Children's blood and household dust, water, soil, and paint were analyzed for lead, and interviews were conducted to ascertain risk factors for elevated blood lead (> or = 10 micrograms/dL). RESULTS: Children's mean blood lead level was 7.7 micrograms/dL. In addition to dust lead loading (micrograms of lead per square foot), independent predictors of children's blood lead were Black race, soil lead levels, ingestion of soil or dirt, lead content and condition of painted surfaces, and water lead levels. For dust lead standards of 5 micrograms/sq ft, 20 micrograms/sq ft, and 40 micrograms/sq ft on noncarpeted floors, the estimated percentages of children having blood lead levels at or above 10 micrograms/dL were 4%, 15%, and 20%, respectively, after adjusting for other significant covariates. CONCLUSIONS: Lead-contaminated house dust is a significant contributor to lead intake among urban children who have low-level elevations in blood lead. A substantial proportion of children may have blood lead levels of at least 10 micrograms/dL at dust lead levels considerably lower than current standards. [ABSTRACT FROM AUTHOR]

Objective: To determine if the presence of a disrupted marriage or living alone would be an independent prognostic risk factor for a subsequent major cardiac event following an initial myocardial infarction.Design: Prospective evaluation in the placebo wing of a randomized, double-blind drug trial in patients with an enzyme-documented acute myocardial infarction who were admitted to a coronary care facility. Data for living alone and/or a marital disruption were entered into a Cox proportional hazards model constructed from important physiologic and nonphysiologic factors in the same database.Setting: Multicenter trial in a mixture of community and academic hospitals in the United States and Canada.Patients: All consenting patients who were 25 to 75 years of age and without other serious diseases were enrolled (placebo, N = 1234) within 3 to 15 days of the index infarction and followed for a period of 1 to 4 years (mean, 2.1 years). Nine hundred sixty-seven patients were followed for 1.1 years and 530 for 2.2 years.Primary Outcome Measure: Recurrent major cardiac event (either recurrent nonfatal infarction or cardiac death).Results: Living alone was an independent risk factor, with a hazard ratio of 1.54 (95% confidence interval, 1.04 to 2.29; P less than .03). Using the Kaplan-Meier statistical method for calculation, the recurrent cardiac event rate at 6 months was 15.8% in the group living alone vs 8.8% in the group not living alone. Risk remained significant throughout the follow-up period (P = .001). A disrupted marriage was not an independent risk factor.Conclusion: Living alone but not a disrupted marriage is an independent risk factor for prognosis after myocardial infarction when compared with all other known risk factors. [ABSTRACT FROM AUTHOR]

Objective: --To determine the necessary length of stay for patients admitted to the hospital with an exacerbation of chronic pulmonary disease and to compare this with the length of stay assigned by the diagnosis related group system.Design: --A cohort of patients were followed up prospectively after hospital admission to determine when complications, critical incidents, and the need for monitoring occurred. The medically derived necessary lengths of stay were statistically compared with the lengths of stay assigned by the diagnosis related group. Clinical factors were used to predict long vs short necessary lengths of stay.Setting: --Two acute care hospitals: one was the principal and the other a major community teaching hospital.Patients: --A consecutive sample of 83 patients who were 45 years of age or older and who required admission for treatment of chronic pulmonary disease.Main Outcome Measures: --The occurrence and time of complications, critical interventions, and monitoring.Results: --After 6 days in the hospital, 90% of patients were free of complications or the need for monitoring. However, 16 days elapsed before 90% of patients had been discharged from the hospital. The length of stay that was considered necessary for care averaged 6.9 days; the actual mean length of stay was 8.7 days. The correlation between each patient's ideal length of stay and the length of stay assigned by the diagnosis related group was low and was not statistically significant. Three clinical variables at the time of admission (high PCO2 levels, symptoms that were present for more than 1 day, and antibiotic treatment) were associated with the need for longer hospital stays.Conclusions: --The medically required length of stay for patients with an exacerbation of chronic pulmonary disease was between 6 and 7 days, on average. This length of stay, which was based on clinical events, differs from the length of stay that was calculated as a statistical norm by the diagnosis related group system. Clinical characteristics may help to identify patients who require a longer length of stay. [ABSTRACT FROM AUTHOR]