Francisco-Javier Gonzalez-Barcala

Truck traffic related air pollution associated with asthma symptoms in young boys: a cross-sectional study

OBJECTIVES The aim of this study was to evaluate the influence of intensity of truck traffic on asthma symptomatology, and its relationship with age and gender. STUDY DESIGN A cross-sectional study was conducted on children and adolescents from Galicia (North-West Spain). METHODS Following the methodology of the International Study of Asthma and Allergies in Childhood (ISAAC): children from schools randomly selected, answered a self-administered questionnaire included questions on asthma symptoms and some risk factors. The association between self-reported truck traffic on the street of residence and symptoms of asthma were investigated by logistic regression adjusted for body mass index, maternal education and parental smoking. RESULTS Almost 40% of children in Galicia are exposed to the frequent and constant passing of heavy goods vehicles. The odds of 6-7 year-old boys having severe or exercise induced asthma is tripled when they live in streets with the constant passing of heavy goods vehicles, compared with those living in streets where these vehicles never pass. In adolescents and 6-7 year-old girls, no relationship was observed between truck traffic and asthma symptoms. CONCLUSIONS The results of this study appear to support a distinct effect of truck traffic on asthma symptoms depending on the age and sex of the exposed population, being more harmful for young males.

Do Low Molecular Weight Agents Cause More Severe Asthma than High Molecular Weight Agents

Introduction The aim of this study was to analyse whether patients with occupational asthma (OA) caused by low molecular weight (LMW) agents differed from patients with OA caused by high molecular weight (HMW) with regard to risk factors, asthma presentation and severity, and response to various diagnostic tests. Methods Seventy-eight patients with OA diagnosed by positive specific inhalation challenge (SIC) were included. Anthropometric characteristics, atopic status, occupation, latency periods, asthma severity according to the Global Initiative for Asthma (GINA) control classification, lung function tests and SIC results were analysed. Results OA was induced by an HMW agent in 23 patients (29%) and by an LMW agent in 55 (71%). A logistic regression analysis confirmed that patients with OA caused by LMW agents had a significantly higher risk of severity according to the GINA classification after adjusting for potential confounders (OR = 3.579, 95% CI 1.136–11.280; p = 0.029). During the SIC, most patients with OA caused by HMW agents presented an early reaction (82%), while in patients with OA caused by LMW agents the response was mainly late (73%) (p = 0.0001). Similarly, patients with OA caused by LMW agents experienced a greater degree of bronchial hyperresponsiveness, measured as the difference in the methacholine dose-response ratio (DRR) before and after SIC (1.77, range 0–16), compared with patients with OA caused by HMW agents (0.87, range 0–72), (p = 0.024). Conclusions OA caused by LMW agents may be more severe than that caused by HMW agents. The severity of the condition may be determined by the different mechanisms of action of these agents.

Role of Blind Closed Pleural Biopsy in the Management of Pleural Exudates

INTRODUCTION The performance of blind closed pleural biopsy (BCPB) in the study of pleural exudates is controversial. OBJECTIVE To assess the diagnostic yield of BCPB in clinical practice and its role in the study of pleural exudates. METHODS Data were retrospectively collected on all patients who underwent BCPB performed between January 1999 and December 2011. RESULTS A total of 658 BCPBs were performed on 575 patients. Pleural tissue was obtained in 590 (89.7%) of the biopsies. A malignant pleural effusion was found in 35% of patients. The cytology and the BCPB were positive in 69.2% and 59.2% of the patients, respectively. Of the patients with negative cytology, 21 had a positive BCPB (diagnostic improvement, 15%), which would have avoided one pleuroscopy for every seven BCPBs that were performed. Of the 113 patients with a tuberculous effusion, granulomas were observed in 87 and the Lowenstein culture was positive in an additional 17 (sensitivity 92%). The overall sensitivity was 33.9%, with a specificity and positive predictive value of 100%, and a negative predictive value of 71%. Complications were recorded in 14.4% of patients (pneumothorax 9.4%; chest pain 5.6%; vasovagal reaction, 4.1%; biopsy of another organ 0.5%). CONCLUSIONS BCPB still has a significant role in the study of a pleural exudate. If an image-guided technique is unavailable, it seems reasonable to perform BCPB before resorting to a pleuroscopy. These results support BCPB as a relatively safe technique.

Trends of Asthma Mortality in Galicia from 1993 to 2007

Introduction. In the past few years, deaths due to asthma appear to decrease at least in Western countries; but there are significant variations between populations. The aim of this study is to describe the trends in deaths due to asthma between 1993 and 2007 in our community and to analyze any factors associated with this. Methods. All cases, which had asthma as a cause of death, were included in the study. The mortality data were obtained from the official death certificate from the Deaths Register. Mortality relative risk, based on the calendar year, sociodemographic variables (age and gender), seasons, and days of the week, were estimated using a Poisson generalized linear model with a log-link. Results. In the 15 years of the study period, a total of 1180 people had died due to asthma, mainly in winter (34.5%), women (64.5%), and advanced age (65 years or above; 84.6%). A tendency of decreased mortality in all age groups was observed during the period of the study, which was significant in both the sexes in the 35- to 64-year-old age group, and in males above 65 years. Conclusion. Death due to asthma is changing favorably in our community, with a tendency to decrease in the past few years. Advanced age, being female, and the winter period are associated with a higher mortality rate due to asthma.

Characteristics and Prognosis of Near-Fatal Asthma Exacerbations

Background:Asthma remains a major public health concern because of its high prevalence and the costs it generates. Near-fatal asthma (NFA) episodes represent the most severe forms of the disease after fatal asthma with significant variations in their incidence between different populations. Objective:To analyze the episodes of NFA over a period of 11 years in the hospital. Methods:The authors retrospectively reviewed all admissions due to asthma exacerbation in our hospital between 2000 and 2010 for patients over 18 years of age. Results:The study included 400 NFA episodes of 285 patients (74% women; mean age 66 years). Of these patients, 228 (80%) had a single episode of NFA and 57 had more than 1 episode during the study period. The authors observed no clear upward or downward trend during the study period. Readmitted patients had more comorbidities, poorer lung function, more severe forms of asthma and more admissions in the year before the index admission. There was a mortality rate of 3.1%. More than 20% of patients were not given controller treatment and more than 40% of patients were not treated with inhaled corticosteroids (ICS). Conclusions:NFA episodes are still prevalent in the population of patients with asthma. Reasons for this could be related to improper management in the stable phase, as suggested by the low rate of patients treated with ICS. It also seems necessary to optimize patient management during hospitalization because stays appear prolonged in comparison with studies in other countries.

Specific inhalation challenge: the relationship between response, clinical variables and lung function

Introduction The specific inhalation challenge (SIC) is considered the gold standard for the diagnosis of occupational asthma (OA). However, its use is not standardised, and the intensity of exposure is regulated empirically. The aim of this study was to identify clinical variables and/or pulmonary function variables able to predict the scale of patients’ response to SIC. Material and methods All patients who underwent SIC at our centre between 2005 and 2013 were studied. Anthropometric characteristics, atopic status, type of causal agent, latency times, pulmonary function tests and SIC results were analysed. Results Two hundred and one patients (51% men) were assessed, of whom 86 (43%) had positive SIC. In the patients with positive results, 29 (34%) were exposed to high molecular weight (HMW) agents and 57 (64%) to low molecular weight (LMW) agents. Patients with a positive SIC exposed to HMW agents had a higher fall in FEV1 after SIC compared with those exposed to LMW agents (p=0.036). The type of asthmatic reaction after SIC also differed between the groups (p=0.020). The logistic regression analysis showed that patients with a higher PC20 before SIC were less likely to have severe decreases in FEV1 after SIC after adjusting for potential confounders (OR=0.771, 95% CI 0.618 to 0.961, p=0.021). Conclusions The scale of the response to SIC is influenced mainly by the degree of bronchial hyper-responsiveness, regardless of whether the causative agent is HMW or LMW, or whether the response is early or late.

One-year and long-term mortality in patients hospitalized for chronic obstructive pulmonary disease

BACKGROUND Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. Identifying potentially-modifiable predictors of mortality could help optimize COPD patient management. The aim of this study is to determine long-term mortality following hospitalization due to acute exacerbations of COPD (AECOPD), as well as AECOPD mortality predictors. METHODS We conducted a retrospective study by reviewing the medical records of all patients admitted with AECOPD in the University Hospital Complex of Santiago de Compostela in 2007 and 2008. In order to identify variables independently associated with mortality, we conducted a multivariate Cox proportional hazard regression analysis including those variables which proved to be significant in the univariate analysis. RESULTS Seven hundred and fifty seven patients were assessed. Patient mean age was 74.8 years and males accounted for 77% of all patients. Mean stay was 12.2 days. Three point six percent of all patients required intensive care. As for mortality rates, 1-year mortality was 26.2%, and 5-year mortality was 64.3%. In both scenarios, the most frequent causes of death were respiratory and cardiovascular disorders. Factors independently associated with mortality were older age, hospitalization by internal medicine (IMU), length of stay, the need for mechanical ventilation (MV) or noninvasive mechanical ventilation (NIV), early readmission, and history of atrial fibrillation (AF) and dementia. CONCLUSIONS In patients with COPD, age, exacerbation severity and comorbidity have long-term prognostic significance.

Association between blood eosinophil count with asthma hospital readmissions

INTRODUCTION The presence of eosinophils in asthma inflammation is a relevant factor in the pathophysiology of the disease, however the relationship between the blood eosinophil count (BEC) with asthma severity and prognosis is still under debate. The aim of this work is to analyze the relationship between the BEC levels and hospital readmissions in patients with asthma. MATERIAL AND METHODS A review was retrospectively carried out on all admissions of patients over 18 years old due to exacerbation of asthma occurring in our hospital between the years 2000 and 2010. The personal characteristics and the asthma personal history of each patient were recorded. The BEC was determined from the first blood sample taken from the patient after their arrival at the hospital. Hospital early, late and frequent readmissions were analyzed using 4 cut-off points; less than 150 eosinophils/μL vs ≥150/μL, less than 200 vs 200 /μL, less than 300 vs ≥300/μL, and less than 400 vs ≥400/μL. RESULTS We have included 1316 patients, 70% of whom are women, as well as a mean age of 60 years, and a mean FEV1 of 73.5% of the reference value. The mean eosinophil blood count was 201.7 cells/μL. A BEC ≥300 cells/μL showed a reduction of risk of late readmission of 42%, a BEC ≥400 cells/μL showed a reduction in late readmission risk of 41% and decrease in frequent late readmission of 63%. CONCLUSIONS Our study appears to support that an elevated BEC is associated with a lower incidence of asthma hospital readmissions.

The association between paracetamol and asthma is still under debate.

ABSTRACT Objective: To analyse the relationship between paracetamol and asthma. Data sources: An English literature search using electronic search engines (PubMed and EMBASE) was conducted. Study selections: Articles published in peer-review journals, from 1990 to December 2015 were included. To perform the search for the most suitable and representative articles, keywords were selected (“asthma,” “paracetamol” and “acetaminophen”). The evidence level was rated according to the criteria of the Oxford Centre For Evidence-Based Medicine. Results: The exposure to paracetamol during pregnancy was analysed in several cohort studies, showing an association between the prenatal exposure to paracetamol with suffering from asthma or presence of wheezing in childhood, especially for persistent wheezing. Nevertheless, a recent study concluded that the relationship between asthma and paracetamol is explained, at least in part, by confounding factors. Several works have also associated the exposure to paracetamol in the first years of life or in adults with the development of childhood asthma. Several pathophysiological mechanisms are known that could explain this relationship, such as the glutathione pathway, the decrease in the release of Th1 cytokines that are normally produced during febrile episodes, which would then lead to a predominance of Th2 cytokines, the cytotoxic effect of paracetamol for pneumocytes, a modulator effect on the activity of myeloperoxidase, as well as the possible antigenic effect of paracetamol, mediated by IgE. Conclusions: There are many arguments that suggest a relationship between the use of paracetamol with the appearance of asthmatic symptoms, however the evidence is inconclusive.

Cross-sectional study about impact of parental smoking on rhinitis symptoms in children

Assess the prevalence of rhinitis and exposure to environmental tobacco smoke (ETS) of children in our community and its relationship with symptoms of rhinitis