The APHEA 2 project investigated short-term health effects of particles in eight European cities. In each city associations between particles with an aerodynamic diameter of less than 10 microm (PM(10)) and black smoke and daily counts of emergency hospital admissions for asthma (0-14 and 15-64 yr), chronic obstructive pulmonary disease (COPD), and all-respiratory disease (65+ yr) controlling for environmental factors and temporal patterns were investigated. Summary PM(10) effect estimates (percentage change in mean number of daily admissions per 10 microg/m(3) increase) were asthma (0-14 yr) 1.2% (95% CI: 0.2, 2.3), asthma (15-64 yr) 1.1% (0.3, 1.8), and COPD plus asthma and all-respiratory (65+ yr) 1.0% (0.4, 1.5) and 0.9% (0.6, 1.3). The combined estimates for Black Smoke tended to be smaller and less precisely estimated than for PM(10). Variability in the sizes of the PM(10) effect estimates between cities was also investigated. In the 65+ groups PM(10) estimates were positively associated with annual mean concentrations of ozone in the cities. For asthma admissions (0-14 yr) a number of city-specific factors, including smoking prevalence, explained some of their variability. This study confirms that particle concentrations in European cities are positively associated with increased numbers of admissions for respiratory diseases and that some of the variation in PM(10) effect estimates between cities can be explained by city characteristics.
The objective of the study was to evaluate the risk of asthma in children who had undergone an adenoidectomy, an operation frequently performed on children with glue ear or recurrent otitis media. Two surveys were carried out, a nation-wide questionnaire returned by 483 individuals (survey A) and a survey of hospital discharge records involving 1616 children who had undergone an adenoidectomy and 161 control children who had undergone probing of the nasolacrimal duct due to congenital obstruction (survey B). The questionnaire (survey A) showed that an adenoidectomy before the age of 4 years was associated with asthma (OR 3.19, 95% CI 1.25; 8.13) and with allergy to animal dust (OR 2.50, 95% CI 1.27; 4.95). In survey B, asthma diagnosis was retrieved from the national asthma register. It showed also that adenoidectomy at an early age was associated with an increased risk of asthma (OR 6.74, 95% CI 2.99; 15.2). There was an association between asthma and adenoidectomy, even before adenoidectomy had actually been performed. The risk of asthma was highest among children who had had adenoidectomy because of recurrent otitis media. The observed association between an adenoidectomy and asthma may be explained by an underlying factor predisposing to both recurrent otitis media and asthma.
We aimed to investigate the potential causal associations of adiposity with asthma overall, asthma by atopic status or by levels of symptom control in a large adult population and stratified by sex. We also investigated the potential for reverse causation between asthma and risk of adiposity.
We performed a bidirectional one-sample Mendelian randomisation (MR) study using the Norwegian Nord-Trøndelag Health Study population including 56 105 adults. 73 and 47 genetic variants were included as instrumental variables for body mass index (BMI) and waist-to-hip ratio (WHR), respectively. Asthma was defined as ever asthma, doctor-diagnosed asthma and doctor-diagnosed active asthma, and was further classified by atopic status or levels of symptom control. Causal OR was calculated with the Wald method.
The ORs per 1 SD (4.1 kg/m2) increase in genetically determined BMI were ranged from 1.36 to 1.49 for the three asthma definitions and similar for women and men. The corresponding ORs for non-atopic asthma (range 1.42-1.72) appeared stronger than those for the atopic asthma (range 1.18-1.26), but they were similar for controlled versus partly controlled doctor-diagnosed active asthma (1.43 vs 1.44). There was no clear association between genetically predicted WHR and asthma risk or between genetically predicted asthma and the adiposity markers.
Our MR study provided evidence of a causal association of BMI with asthma in adults, particularly with non-atopic asthma. There was no clear evidence of a causal link between WHR and asthma or of reverse causation.
The effects of pre- or postnatal passive smoking on the adult incidence of asthma have not been reported previously. Between 1985 and 1996/1997, we conducted an 11-year community cohort study on the incidence of asthma and respiratory symptoms in Western Norway. The cohort included 3,786 subjects aged 15 to 70 years, of which 2,819 were responders at both baseline and follow-up. The incidence of asthma and five respiratory symptoms by self-reported exposure to maternal smoking in utero and in childhood, as well as smoking by other household members in childhood, was examined. After adjustment for sex, age, education, hay fever, personal smoking, and occupational exposure, maternal smoking was associated with asthma, phlegm cough, chronic cough, dyspnea grade 2, attacks of dyspnea, and wheezing, with odds ratios (95% confidence intervals [CI]) of 3.0 (1.6, 5.6), 1.7 (1.1, 2.6), 1.9 (1.2, 3.0), 1.9 (1.2, 3.0), 2.0 (1.3, 3.0), and 1.4 (0.9, 2.2), respectively. The adjusted attributable fractions (95% CI) of the adult incidence of asthma were 17.3% (5.2, 27.9) caused by maternal smoking and 9.3% (95% CI, -23.2, 33.2) caused by smoking by other household members. Exposure to pre- and postnatal smoking carries a substantial risk for developing adult asthma and respiratory symptoms.
To evaluate the association between hospitalisation for respiratory syncytial virus lower respiratory tract infection (RSV LRTI) in infancy and asthma, respiratory health-related quality of life and lung function at 28-31 years of age.
In 2010, we carried out a 30-year follow-up on 43 adults admitted to Kuopio University Hospital, Finland, for RSV LRTI, 27 for bronchiolitis and 16 for pneumonia, between 1981 and 1982. Together with 86 population-based controls, they completed the Saint George's Respiratory Questionnaire and underwent prebronchodilator (pre-BD) and post-BD spirometry tests to measure percentage of predicted forced vital capacity (FVC%), percentage of predicted forced expiratory volume in 1 sec (FEV1%) and percentage of predicted FEV1/FVC (FEV1/FVC%).
Both the pre-BD and post-BD FEV1% and FEV1/FVC% were significantly lower in former RSV LRTI patients than in the controls. The bronchiolitis patients had more asthma in adulthood than the controls and pneumonia in infancy was associated with lower St George's Respiratory Questionnaire (SGRQ) scores.
Respiratory tract infection LRTI hospitalisation in infancy was associated with an increased risk of permanent obstructive lung function reduction in adulthood. The asthma risk was higher after hospitalisation for bronchiolitis, than in the controls, and respiratory health-related quality of life was lower after hospitalisation for pneumonia.
The city of Windsor is recognized to have poor air quality in comparison with other Canadian cities. However, relatively few studies have evaluated associations between day-to-day fluctuations in air pollution levels and respiratory health in Windsor. In this study, we examined associations between short-term changes in ambient air pollution and emergency department (ED) visits for asthma in Windsor.
A time-stratified case-crossover design was applied to 3,728 ED visits for asthma that occurred in Windsor area hospitals between 2002 and 2009. Daily air pollution levels for the region were estimated using Environment Canada's network of fixed-site monitors. ED visits were identified through the National Ambulatory Care Reporting System (NACRS). Odds ratios and their corresponding 95% confidence intervals were estimated using conditional logistic regression, and were adjusted for the confounding influence of daily number of influenza ED visits and weather variables using natural spline functions.
Statistically significant associations were observed between ambient air pollution levels and ED visits for asthma in Windsor. Effects were particularly pronounced among children 2 to 14 years of age between April and September. Namely, increases in the interquartile range with 1-day lagged exposure to SO2, NO2 and CO levels were associated with increased risks of an asthma visit of 19%, 25% and 36%, respectively.
Exposure in Windsor to ambient air pollution increases the risk of ED visits for asthma, particularly among children.
The article presents results of descriptive epidemiologic study of bronchial asthma among children in Moscow where the incidence is steadily growing. Since 1947 average prevalence of bronchial asthma in Moscow has increased over 7 times, being considerably uneven over the territory. The average prevalence equals 6.9/1,000, but on 56% of the territory it is double higher. Sites of the higher occurrence are localized in the living area situated near the Zoo, horse races, perfume factory and other enterprises, near major automobile roads. Statistic analysis of the prevalence if correlated with concentrations of pollutants in the air proved that nitrogen oxides induce 60% of the cases. No differences in some risk factors (heredity, living conditions, etc.) were revealed by the poll among families of the ailing children residing in the districts with variable air pollution. The results helped to restructure pediatric allergologic service in the city.
We wanted to assess relations between the daily occurrence of asthma symptoms and fluctuations of air pollution concentrations and meteorological conditions. In a panel of 31 asthmatic patients residing in the town of Piteå in northern Sweden, severe symptoms of shortness of breath, wheeze, cough and phlegm were recorded in an asthma diary together with suspected causes. Sulphur dioxide, nitrogen dioxide, black smoke, relative humidity and temperature were used to evaluate the relationship to the environment. By using multivariate analyses, we found that daily variations in the particulate pollution levels, indicated by black smoke levels below the criteria limits, had significant effects on the risk of developing severe symptoms of shortness of breath. This association was stronger among 10 subjects, who had at least five incident days with severe shortness of breath. Meteorological conditions were not significant in the multivariate models. Cough and phlegm did not show significant relationships to any environmental condition that was evaluated. Only one-third of the subjects reported, at least once during the study, symptoms believed to be related to air pollutants, although we found significant correlations between the pollution levels and the frequency of pollution-related symptoms. We conclude that an association has been established for black smoke as pollutant and shortness of breath as respiratory symptom, and that in certain asthmatics, effects were occurring at lower particulate levels than suggested previously.
There is little information of lower respiratory symptoms, bronchial hyperresponsiveness and airway inflammation in elite ice hockey players. A total of 88 highly trained ice hockey players and 47 control subjects were studied. All the subjects were subjected to skin-prick tests, resting spirometry examinations and histamine-challenge tests. Adequate induced sputum samples were obtained from 68 of the ice hockey players and from 18 symptom-free control subjects on a separate day. Bronchial hyperresponsiveness in a histamine-challenge test was found in 21 (24%) of the athletes and in five (11%) of the controls. Current asthma (current asthmatic symptoms and increased bronchial responsiveness) was observed in 13 (15%) of the athletes and in one (2%) of the control subjects. Total asthma (current asthma or previously physician-diagnosed asthma) occurred in 19 (22%) of the athletes and in two (4%) of the controls. Atopy, according to skin-prick tests, was observed in 51 (58%) of the athletes and 17 (36%) of the control subjects. The differential cell counts of eosinophils (2.6 versus 0.2%) and neutrophils (80.9 versus 29.9%) in the sputum samples of the ice hockey players were significantly higher than in those of the control subjects. Asthma is common in elite ice hockey players and they show signs of a mixed type of neutrophilic and eosinophilic airway inflammation. Inhalation of cold air associated with exposure to indoor pollutants during intensive training is a possible causative factor.