Respiratory symptoms in children living near busy roads and their relationship to vehicular traffic: results of an Italian multicenter study (SIDRIA 2).

BACKGROUND: Epidemiological studies have provided evidence that exposure to vehicular traffic increases the prevalence of respiratory symptoms and may exacerbate pre-existing asthma in children. Self-reported exposure to road traffic has been questioned as a reliable measurement of exposure to air pollutants. The aim of this study was to investigate whether there were specific effects of cars and trucks traffic on current asthma symptoms (i.e. wheezing) and cough or phlegm, and to examine the validity of self-reported traffic exposure. METHODS: The survey was conducted in 2002 in 12 centers in Northern, Center and Southern Italy, different in size, climate, latitude and level of urbanization. Standardized questionnaires filled in by parents were used to collect information on health outcomes and exposure to traffic among 33,632 6-7 and 13-14 years old children and adolescents. Three questions on traffic exposure were asked: the traffic in the zone of residence, the frequency of truck and of car traffic in the street of residence. The presence of a possible response bias for the self-reported traffic was evaluated using external validation (comparison with measurements of traffic flow in the city of Turin) and internal validations (matching by census block, in the cities of Turin, Milan and Rome). RESULTS: Overall traffic density was weakly associated with asthma symptoms but there was a stronger association with cough or phlegm (high traffic density OR = 1.24; 95% CI: 1.04, 1.49). Car and truck traffic were independently associated with cough or phlegm. The results of the external validation did not support the existence of a reporting bias for the observed associations, for all the self-reported traffic indicators examined. The internal validations showed that the observed association between traffic density in the zone of residence and respiratory symptoms did not appear to be explained by an over reporting of traffic by parents of symptomatic subjects. CONCLUSION: Children living in zones with intense traffic are at higher risk for respiratory effects. Since population characteristics are specific, the results of validation of studies on self-reported traffic exposure can not be generalized.

[Asthma attacks at school in Italian adolescents]. / Attacchi di asma a scuola negli adolescenti italiani.

We evaluated the occurrence of asthma attacks at school in a sample of 13,266 adolescents (13-14 year old) from 12 centers across Italy (SIDRIA-2 study). 23.8% of asthmatic subjects reported at least one wheezing attack at school in the previous 12 months. The attacks occurred in the gymnasium (55.4%), in the classroom (42.6%), outside (28.7%), in the bathroom (4.5%) and in other school environments (4%). During the attacks, self-administration of a bronchodilator was reported by 66% of the subjects. Educational programs and specific guidelines to deal with asthmatic schoolchildren are warranted.

[Frequency of asthma and allergies in Italian children and adolescents: results from SIDRIA-2]. / La prevalenza di asma e allergie nei bambini e adolescenti italiani: i risultati del progetto SIDRIA-2.

The present study investigated the prevalences of asthma, allergic rhinitis (both to pollen and to other causes) and eczema in Italian children (6-7 yr old) and adolescents (13-14 yr old) in the second phase of SIDRIA (2002), aiming also to highlight geographical differences in the prevalence of the studied diseases. Prevalence of lifetime asthma is 9.3% in children and 10.3% in adolescents; lifetime prevalences of allergic rhinitis and eczema are 12.3% and 15.9% in children, 20.9% and 11.9% in adolescents. In both age groups, prevalence of lifetime asthma and lifetime and past 12 months wheezing was greater in central than in northern and southern areas. A similar situation was also seen for allergic rhinitis but not for eczema whose prevalence decreased between North to South of Italy. An excess in prevalence of lifetime asthma and rhinitis was found in metropolitan areas compared to other areas; prevalence of eczema did not show any difference by urbanization level. Prevalence of asthma and, only in children, prevalence of rhinitis symptoms was greater in males than in females. On the contrary, prevalence of eczema and, only in adolescents, prevalence of rhinitis symptoms was greater in females. Prevalence of childhood asthma, allergic rhinitis and eczema in Italy ranks intermediate with respect to other countries participating in ISAAC phase three.