Air Pollution Effects on Ventilatory Function of US Schoolchildren

The ventilatory performance of elementary schoolchildren living in neighborhoods of high and low air pollution in Cincinnati, Chattanooga, and New York was evaluated by in-school measurements of three-quar- ter second forced expiratory volume (FEV_0.75). A consistent relationship between impaired ventilatory function in children 5 to 13 years of age and exposure to particulates plus sulfur oxide was demonstrated. In the Cincinnati study, performance of children in polluted neighborhoods improved during seasons of low pollution but not to the level of their counterparts in low exposure neighborhoods. In New York, results in children age 9 to 13 years indicate that early exposure for five to ten years to elevated air pollution levels was accompanied by a prolonged decrement in ventilatory function. Inconsistent and barely significant effects on lung function were found in Chattanooga where high exposures to nitrogen dioxide had occurred for only two to three years prior to the study.     

Surgery in heart and lung transplant patients

BACKGROUND: Heart and lung transplantation is an increasingly successful procedure. After transplant, these patients may need surgery for common diseases and for problems caused by immunosuppression. The purpose of this study was to determine surgical outcomes heart and lung transplant patients after transplantation. METHODS: All patients in the cardiopulmonary transplant registry were reviewed. Data collected included sex, age at transplantation, age at subsequent procedure, number and type of surgical procedures performed, number and type of postoperative complications, grade of complications (using the Clavien classification), and outcome (discharge to home, disabled, dead). RESULTS: During a 15-year period, 222 (64%) of 345 heart or lung transplant patients underwent a surgical procedure. Seven hundred fifty-four procedures were performed (median 3 procedures/patient). Sixty-seven patients suffered 72 complications (10% complication rate). Twenty-one (29%) complications were grade I; 20 (28%) were grade IIA; 21 (29%) were grade IIB; 8 (11%) were grade III; and 2 (3%) were grade IV. Twelve percent of the complications in the heart transplant patients were cardiac in nature, whereas 0% of the complications in the lung transplant patients were pulmonary in nature. There were 475 (63%) discharges to home, 2 (0.2%) inpatient deaths, and 18 (2%) deaths within 30 days; 49 (7%) procedures resulted in disability; and 210 (28%) patients were lost to follow-up. CONCLUSIONS: Heart or lung transplant patients will frequently need subsequent surgical procedures. Overall, the patients tolerated the procedures well, and the morbidity and mortality rates were acceptable. Most complications were not related to the transplanted organ.     

Can endobronchial biopsy analysis be recommended to discriminate between asthma and COPD in routine practice?

BACKGROUND: International guidelines stress the importance of accurately discriminating between asthma and chronic obstructive pulmonary disease (COPD). Although characteristic pathological features have been described for both conditions, their discriminatory power has never been systematically assessed. METHODS: Endobronchial biopsy (EBB) specimens from patients with a clear clinical diagnosis of asthma and COPD (50 per group) were examined by three pathologists in a double blind manner. They were asked to propose a pathological diagnosis of either asthma or COPD and to analyse qualitatively the most frequent abnormalities reported in the literature. RESULTS: The sensitivity and specificity of EBB ranged from 36% to 48% and from 56% to 79%, respectively. Eosinophils strongly biased the pathological diagnoses in favour of asthma, whereas their estimated prevalence was similar (11-37% in asthma and 13-41% in COPD). Metaplasia (11-39% in COPD, 1-18% in asthma) and epithelial inflammation (28-61% in COPD, 11-38% in asthma) tended to be specific to COPD, whereas epithelial desquamation (80-98% in asthma, 61-88% in COPD) and basement membrane thickening (71-94% in asthma, 53-88% in COPD) tended to be associated with asthma. There was acceptable intra- and inter-observer agreement only for metaplasia and epithelial eosinophils. CONCLUSIONS: Specific histopathological features of asthma and COPD probably exist, but current routine analysis procedures to assess EBB specimens are not sufficiently discriminatory. This might be rectified by improving pathological definitions.     

Evaluation of platelets in heart failure: is platelet activity related to etiology,functional class,or clinical outcomes?

Objectives We sought to determine whether platelet activity in patients with heart failure is related to an ischemic versus nonischemic etiologic condition, clinical disease severity, or adverse clinical outcomes. Background Platelet activity may affect outcome in patients with heart failure. A prospective evaluation of the relation of baseline platelet function to etiologic condition, New York Heart Association (NYHA) class, and clinical outcomes has not been previously reported. Methods Ninety-six consecutive outpatients with ambulatory heart failure with an ejection fraction <0.40 and NYHA Class II to IV symptoms who presented to the Duke Heart Failure Clinic and 14 healthy control subjects formed the study groups. Baseline characteristics and blood analyzed for thromboxane (Tx) B₂, 6-keto PGF_1α, platelet contractile force, adenosine diphosphate/collagen shear-induced closure time, whole blood aggregation and CD41, CD31, CD62p, and CD51/CD61 by flow cytometry were determined. Survival status and hospitalizations were determined in the heart failure patient cohort. Results The median age of patients was 65 years (22% female, 64% white). An ischemic etiologic condition was present in 61% of patients. The population had mild to moderate heart failure: NYHA class I (1%), II (41%), III (46%), and IV (12.5%) and severe ventricular dysfunction (median ejection fraction = 0.20). There were 39 clinical events (7 deaths, 3 cardiac transplants, 29 other first hospitalizations) in 305 median days of observation. Platelet activity, indicated by whole blood aggregation with 5 μmol adenosine diphosphate (P = .04) and Tx B₂ (P = .01), was higher in patients with heart failure. Whole blood aggregation was greater than the 90th percentile in 22% of patients with heart failure versus 7% of control subjects. Platelet function did not differ for any of the markers between the ischemic and nonischemic groups and was not affected by antecedent aspirin. There was no relation of NYHA class or the occurrence of events to platelet activity. Conclusion Platelet activity is heightened in 22% of outpatients with stable heart failure symptoms and is not affected by antecedent aspirin therapy. The degree of platelet activation is similar in ischemic and nonischemic patients with heart failure and is not related to clinical disease severity. Current methods to assess platelet activation do not appear to predict outcome. (Am Heart J 2002;143:1068-75.)     

The failure of orally administered glycoprotein IIb/IIIa inhibitors to prevent recurrent cardiac events

PURPOSE: Despite the success of intravenous glycoprotein IIb/IIIa antagonists, oral formulations have failed to show benefit and have been associated with increased mortality. To understand these findings, we performed a meta-analysis of results from four phase 3 trials. SUBJECTS AND METHODS: Trials were identified by MEDLINE search; review of abstracts from American College of Cardiology, European Society of Cardiology, and American Heart Association scientific sessions; or querying investigators in the field. Published, phase 3, randomized, placebo-controlled trials involving more than 1000 patients with coronary artery disease that compared an oral glycoprotein IIb/IIIa antagonist with or without background aspirin versus aspirin, and that had a planned follow-up of > or =30 days, were included. Four trials met these criteria. Odds ratios (ORs) and 95% confidence intervals (CIs) were generated from results, and combined using an empirical Bayes random-effects model. RESULTS: Among 33,326 patients, oral glycoprotein IIb/IIIa agents were associated with 31% increased mortality (OR = 1.31; 95% CI: 1.12 to 1.53; P= 0.0001). Results were similar whether the agent was added to (OR = 1.38; 95% CI: 1.15 to 1.67) or substituted for (OR = 1.37; 95% CI: 1.00 to 1.86) aspirin. Ischemic events or sudden death (OR = 1.22; 95% CI: 0.91 to 1.63) were also more common. Among patients with acute coronary syndromes, the incidence of myocardial infarction was increased (OR = 1.16; 95% CI: 1.03 to 1.29). CONCLUSION: Oral glycoprotein IIb/IIIa inhibitor therapy is associated with increased mortality and myocardial infarction. No single explanation for these findings is satisfactory; the problem is likely to be multifactorial.     

Bicycle helmet-wearing variation and associated factors in Ontario teenagers and adults

BACKGROUND: The incidence of bicycle helmet use and the factors associated with helmet use in Ontario are presented in this study. The Ontario Health Survey (1996), a population-based survey of Ontario residents, was used as the data source. METHODS: As the factors associated with helmet use were found to differ between adults and teens, a separate analysis was performed for each age grouping. A logistic regression model (with Bootstrap confidence intervals--95%) was used and adjusted odds ratios (OR) are reported. RESULTS: Of the 7,693 respondents, 41.1% reported wearing their helmets on a regular basis when riding a bicycle. Helmet use was greatest among 12-14 year olds (71.7%) and lowest among those 15-18 years old (33.3%). In teenagers, drinking alcohol (OR: 2.8) and smoking (OR: 4.4) were strongly associated with helmet non-use. In the adult group, female gender (OR: 1.26), higher income (OR: 1.43), higher education (OR: 1.68), nonsmoking status (OR: 2.0) and abstinence from alcohol (1.27) were associated with helmet use. Living in a rural area was also associated with helmet use in the multi-variable analysis. CONCLUSION: This study indicates that bicycle helmet non-use is a multifaceted problem and thus any strategy for increasing helmet-wearing rates requires multi-dimensional interventions. The results of this study are discussed within the context of other studies and related to their public health implications.