Assessing paediatric asthma occurrence through dispensed prescription data and questionnaires.

BACKGROUND: The prevalence of asthma, a common disorder in childhood, is often estimated by cross-sectional studies based on questionnaires, with the drawback that estimates are limited to certain age groups and areas. The use of electronic health data is increasingly allowing researchers to overcome these limitations. This study is aimed at assessing asthma occurrence of a school-aged population in Northeast Italy using two different data sources. METHODS: In 2004, a population-based survey using a standardized questionnaire was conducted to estimate asthma occurrence among a resident population of children aged 6-7 years and adolescents aged 13 years. A selection of dispensed asthma medications was extracted from electronic databases for a 4-year period prior to questionnaire completion (2000-03). Asthma prevalence was estimated by commonly used questionnaire classifications and compared with use of inhaled bronchodilators (alone or in combination) in various time periods. Correlations between the two approaches were calculated. RESULTS: A total of 10 252 subjects were eligible for analysis (85% of the resident population). A total of 4747 subjects (38% of the resident population) were registered in the drug database during 2000-03. Asthma prevalence was higher in males and in children. Congruence between the two enquiry methods varied according to criteria applied and improved with the protraction of the observation period. CONCLUSION: A longer period for the capture of medication data yielded higher congruence. A degree of mismatch was observed between the two methods most likely related to factors of drug use and questionnaire reliability. Nonetheless, the benefits of using easily accessible population data prevail, and further studies are warranted.

[Air pollution and mortality in twenty-five Italian cities: results of the EpiAir2 Project]. / Inquinamento atmosferico e mortalità in venticinque città italiane: risultati del progetto EpiAir2.

OBJECTIVES: this study aims at presenting the results from the Italian EpiaAir2 Project on the short-term effects of air pollution on adult population (35+ years old) in 25 Italian cities. DESIGN: the short-term effects of air pollution on resident people died in their city were analysed adopting the time series approach. The association between increases in 10µg/m(3) in PM10, PM2.5, NO2 and O3 air concentration and natural, cardiac, cerebrovascular and respiratory mortality was studied. City-specific Poisson models were fitted to estimate the association of daily concentrations of pollutants with daily counts of deaths. The analysis took into account temporal and meteorological factors to control for potential confounding effect. Pooled estimates have been derived from random effects meta-analysis, evaluating the presence of heterogeneity in the city specific results. SETTING AND PARTICIPANTS: it was analysed 422,723 deaths in the 25 cities of the project among people aged 35 years or more, resident in each city during the period 2006-2010. MAIN OUTCOME MEASURES: daily counts of natural, cardiac, cerebrovascular, and respiratory mortality, obtained from the registries of each city. Demographic information were obtained by record linkage procedure with the civil registry of each city. RESULTS: mean number of deaths for natural causes ranged from 513 in Rovigo to 20,959 in Rome. About 25% of deaths are due to cardiac diseases, 10% to cerebrovascular diseases, and 7% to respiratory diseases. It was found an immediate effect of PM10 on natural mortality (0.51%; 95%CI 0.16-0.86; lag 0-1). More relevant and prolonged effects (lag 0-5) have been found for PM2.5 (0.78%; 95%CI 0.12-1.46) and NO2 (1.10%; 95%CI 0.63-1.58). Increases in cardiac mortality are associated with PM10 (0.93%; 95%CI 0.16-1.70) and PM2.5 (1.25%; 95%CI 0.17-2.34), while for respiratory mortality exposure to NO2 has an important role (1.67%; 95%CI 0.23-3.13; lag 2-5), as well as PM10 (1.41%; 95%CI - 0.23;+3.08). Results are strongly homogeneous among cities, except for respiratory mortality. No effect has been found for cerebrovascular mortality and weak evidence of association has been observed between ozone and mortality. CONCLUSIONS: a clear increase in mortality associated to air pollutants was observed. More important are the effects of NO2 (on natural mortality), mostly associated with traffic emissions, and of PM2.5 (on cardiac and respiratory mortality). Nitrogen dioxide shows an independent effect from the particulate matter, as observed in the bi-pollutant models.

Asthmatic symptoms and air pollution: a panel study on children living in the Italian Po Valley.

The Po Valley (Northern Italy) has elevated levels of air-pollution due to various sources of pollution and adverse weather conditions. This study evaluates the short-term effects of exposure to particulate matter with a diameter of 10 microns or less (PM10) on asthma symptoms in school-aged children. An initial cross-sectional survey was conducted in the area to estimate asthma prevalence in children. Out of a total of 250 asthmatic children identified by the study, 69 agreed to participate in a panel study. The PM10 exposure assessment was based on a combination of geographic and environmental measurements leading to a focus on three different areas, each characterised by its own daily PM10 level. Participants were monitored daily for respiratory symptoms for eight weeks (January-March 2006). We assessed the relationship between daily PM10 exposure and occurrence of asthma symptoms with a generalised linear model based on a total of 3864 person-days of observation. Exposure to PM10 per m³ was found to be particularly associated with cough (OR=1.03, CI 95% 0.99; 1.08) and phlegm (OR=1.05, CI 95% 1.00; 1.10). In the most polluted area, exposure to PM10 was also associated with wheezing (OR=1.18, CI 95% 1.02; 1.37).