The self-reported density of truck traffic on residential streets and the impact on asthma, hay fever and eczema in young adolescents

Background: Conflicting results have been reported, mostly in developed countries, on the relationship between exposure to traffic and allergic diseases. This study aims to examine the impact of truck traffic on asthma, rhinitis and eczema in early adolescence in Skopje, the capital of the Republic of Macedonia, as a developing country with a lower middle rate of high truck traffic exposure and low prevalence rates of allergic diseases.

Methods: Self-reported data was used, obtained through the International Study of Asthma and Allergies in Childhood Phase 3 written questionnaires, from 3026 adolescents aged 13-14 years from Skopje. Truck traffic density on the street of residence on weekdays was correlated to current and ever-diagnosed asthma, rhinitis and eczema by odds ratios (OR, 95% CI) in binary logistic regression, with and without adjustments for potential confounding factors separately and for their joint effect.

Results: A positive association of truck traffic density appeared to be limited to current dry night cough (aOR: 1.63; 1.07-2.47; aOR: 2.17; 1.40-3.35; and aOR: 2.33; 1.43-3.79 for truck traffic seldom, frequently through the day, and almost the whole day, respectively) with an exposure-response relationship and to current wheeze only for truck traffic almost the whole day (aOR: 1.87; 1.02-3.42).

Conclusion: The findings suggest an aggravating effect of truck traffic on current asthma symptoms, but not on asthma, allergic rhinitis and eczema diagnoses. It seems that it probably has an impact as a direct respiratory irritant in early adolescence.