Outdoor particulate matter and childhood asthma admissions in Athens, Greece: a time-series study

<p>Abstract</p> <p>Background</p> <p>Particulate matter with diameter less than 10 micrometers (PM₁₀) that originates from anthropogenic activities and natural sources may settle in the bronchi and cause adverse effects possibly via oxidative stress in susceptible individuals, such as asthmatic children. This study aimed to investigate the effect of outdoor PM₁₀concentrations on childhood asthma admissions (CAA) in Athens, Greece.</p> <p>Methods</p> <p>Daily counts of CAA from the three Children's Hospitals within the greater Athens' area were obtained from the hospital records during a four-year period (2001-2004, n = 3602 children). Mean daily PM₁₀concentrations recorded by the air pollution-monitoring network of the greater Athens area were also collected. The relationship between CAA and PM₁₀concentrations was investigated using the Generalized Linear Models with Poisson distribution and logistic analysis.</p> <p>Results</p> <p>There was a statistically significant (95% CL) relationship between CAA and mean daily PM₁₀concentrations on the day of exposure (+3.8% for 10 μg/m³increase in PM₁₀concentrations), while a 1-day lag (+3.4% for 10 μg/m³increase in PM₁₀concentrations) and a 4-day lag (+4.3% for 10 μg/m³increase in PM₁₀concentrations) were observed for older asthmatic children (5-14 year-old). High mean daily PM₁₀concentration (the highest 10%; >65.69 μg/m³) doubled the risk of asthma exacerbations even in younger asthmatic children (0-4 year-old).</p> <p>Conclusions</p> <p>Our results provide evidence of the adverse effect of PM₁₀on the rates of paediatric asthma exacerbations and hospital admissions. A four-day lag effect between PM₁₀peak exposure and asthma admissions was also observed in the older age group.</p

Truncated quasi-score function in the 1-dependent and stationary case

The structure of the quasi-score function is investigated when the data is a realization of a 1-dependent and stationary sequence of random variables. A truncated quasi-score function is proposed, which leads to a simplified quasi-score without loss of efficiency.Location parameter m-Dependence Quasi-likelihood Stationarity

Weekend-Weekday Effect Assessment of PM10 in Volos, Greece (2010-2014)

Several epidemiological studies have shown an association between particulate air pollution and adverse health effects. The consensus among the scientific community is that suspended particulate matter is one of the most harmful pollutants, particularly the inhalable particulate matter with aerodynamic diameters less than 10 mu m (PM10) causing respiratory health effects and heart diseases. The effects of aerosols on human health are determined by both their size and their chemical composition. Average daily concentrations exceeding the EU daily threshold concentration appear, among other cases, during Sahara dust episodes, a natural phenomenon that degrades the air quality in the urban area of Volos. The city of Volos is a coastal city of medium size in the eastern seaboard of Central Greece. The main objective of this work is the study of the temporal evolution and the assessment of weekend effect in particulate matter concentration levels in the centre of the city of Volos. PM10 data obtained by a fully automated station that was established by the Hellenic Ministry of Environment and Energy, for a 5-year period (2010-2014) are analyzed in order to study the day-of-week variations during the cold and warm period of the year. As these variations are mostly expected to be due to the human working cycle, a strong weekly cycle would be indicative of the dominance of anthropogenic particles

Estimation of Hospital Admissions Respiratory Disease Attributed to PM10 Exposure Using the AirQ Model Within the Greater Athens Area

The main objective of this work is the assessment of the annual number of hospital admissions for respiratory disease (HARD) due to the exposure to inhalable particulate matter (PM10), within the greater Athens area (GAA), Greece. Towards this aim, the time series of the particulate matter with aerodynamic diameter less than 10 mu m (PM10) recorded in six monitoring stations located in the GAA, for a 13-year period 2001-2013, is used. In this study AirQ2.2.3 software developed by the WHO, was used to evaluate adverse health effects by PM10 in the GAA during the examined period. The results show that, the mean annual HARD cases per 100,000 inhabitants ranged between 20 (suburban location) and 40 (city centre location). Approximately 70 % of the annual HARD cases are due to city centre residents. In all examined locations, a declining trend in the annual number of HARD cases is appeared. Moreover, a strong relation between the annual number of HARD cases and the annual number of days exceeding the European Union daily PM10 threshold value was found

Assessment of the Thermal Comfort Conditions in a University Campus Using a 3D Microscale Climate Model, Utilizing Mobile Measurements

The objective of the study is to assess the human thermal comfort at a University Campus in the metropolitan area of Athens. The equipment setup consists of all the necessary sensors for human thermal comfort estimation along with a high resolution GPS, mounted on a cargo bicycle. The experiment was carried out for midday and night on July 29, 2015. Besides, long term 5 min measurements from a meteorological station, established on the roof of a building within the University Campus, were also used to quantify the mean thermal environment. The densely carried out bicycle measurements every 5 s was the input data utilized by the ENVI-met model; a three-dimensional microclimate model designed to simulate the surface-plant-air interactions in urban environment. The in situ measurements along with the model&apos;s output results reveal the thermal comfort regime of the selected area and the ability of the model to estimate accurately the micrometeorological conditions

Different effects of sensitization to mites and pollens on asthma symptoms and spirometric indices in children: a population-based cohort study

Background: We have previously shown that long-term exposure of children to a highly polluted urban compared with a rural environment is associated with subclinical airway narrowing and increased prevalence of atopy. Objective: To test the hypothesis that sensitization to indoor perennial, compared with seasonal, aeroallergens has distinct effects on asthma symptoms and/or spirometric indices. Methods: We evaluated the respiratory health of 478 and 342 children aged 8 to 10 years living in an urban and a rural area, respectively, during a period of 8 years. Children were evaluated by parental questionnaire in 3 phases, 1995 to 1996 (phase 1), 1999 to 2000 (phase 2), and 2003 to 2004 (phase 3), and by spirometry and skin prick testing to 9 common local aeroallergens in phases 1 and 2. Results: Sensitization to pollens was associated with current wheezing in phase I of the study (odds ratio [OR], 3.36; 95% confidence interval [CI], 1.71 to 6.62; P &lt;.001) but not with spirometric indices. Sensitization to mites was negatively associated with forced expiratory volume in 1 second (95% CI, -7.26 to -0.90; P =.01) and forced expiratory flow at 50% of forced vital capacity (95% CI, - 10.80 to - 1.33; P =.01) in study phase 1 but not in phase 2. Conclusions: Our results indicate that sensitization to mites is associated with insidious involvement of large and small airways, whereas sensitization to pollens is associated with childhood wheezing at the age of 8 to 10 years. Subsequent loss of these associations implies that risk factors other than allergy influence airway disease at a later age

Different effects of urban and rural environments in the respiratory status of Greek schoolchildren

We hypothesized that asthma symptoms and lung function of schoolchildren living in Athens urban area are adversely affected as compared to others living in a rural environment, over a period of 8 years. We recruited 478 and 342 children aged 8-10 years living within a short radius around the urban and rural area monitoring stations, respectively. Respiratory health was assessed by a parent-completed questionnaire in three phases: 1995-1996 (phase-1), 1999-2000 (phase-2), 2003-2004 (phase-3) and by spirometry in phases-1 and 2. Reported asthma and wheeze did not differ in the two areas, whereas cough was more prevalent in the urban area in phase-1. Children from the rural environment had tower levels of percent-predicted forced vital capacity (FVC%) in phase-1 and higher of percent-predicted-forced expiratory flow at mid-FVC (FEF50%) in both phases. Independent associations were detected between FVC% as-well-as FEF50% and residential area. High FVC% was associated with outdoor systemic athletic activities; there was lower FVC% growth in the urban versus the rural area. Nitrogen dioxide and sulfur dioxide were higher in the urban area, whereas ozone concentrations differed less between the two areas. These results suggest that tong-term exposure to urban environment is associated with sub-clinical airway narrowing and slower rate of FVC growth. (c) 2006 Elsevier Ltd. All rights reserved

Association of weather conditions with childhood admissions for wheezy bronchitis or asthma in Athens

Background: The association between asthma morbidity and meteorological conditions is well documented, but it is not clear to what extent more specific meteorological variables are implicated. Objectives: This study was aiming to investigate whether there is any association between specific meteorological conditions and the seasonal variation and the rate of asthma admissions among children in Athens. Methods: Data were obtained retrospectively from hospital registries of the three main Children’s Hospitals in Athens during a 23-year period ( 1978 - 2000). The meteorological database consisted of mean monthly values of eight meteorological variables. The whole period studied was divided into three time periods: 1978 - 1987, 1988 - 1993 and 1994 - 2000. Results: A clear seasonal trend with a permanent pattern was detected. There were more monthly asthma admissions in winter-spring and autumn for younger children, as well as a lower peak in winter and autumn and a major one in May for older children, without significant differences in between the three time periods. The results of a multiple regression analysis revealed that relative humidity and atmospheric pressure were predictors of up to 56.7% ( 1988 - 1993) and 59.2% ( 1994 - 2000) monthly asthma admissions among younger children. No relation of the time trend in asthma admissions during the periods studied for any age group with any of the meteorological variables was detected. Conclusions: Our results indicate a constant seasonal variability in asthma admissions among children in Athens, whereas relative humidity and atmospheric pressure are the more implicated meteorological variables for younger asthmatic children. Copyright (C) 2006 S. Karger AG, Basel