Living near busy roads ‘not linked to asthma and COPD in adults’
MedWire News: Living in close proximity to busy roads is not associated with an increased risk for asthma, allergies, or chronic obstructive pulmonary disease (COPD) in adults, results of a UK study suggest.
“Many epidemiological studies have examined effects of exposure to road vehicle traffic on chronic respiratory and allergic disease in children, but research of the effects in adults is limited,” explain Andrea Venn (University of Nottingham) and colleagues in the journal BMC Pulmonary Medicine.
To address this, the researchers studied data on 2644 adults, aged 18–70 years, who were recruited in 1991 as part of a study of the effect of diet on chronic lung disease. All the participants were living in the Gedling area of Nottingham, which covers the north east suburbs of Nottingham City and surrounding rural villages.
The distance between each participant’s home and the nearest main road was recorded at baseline, along with outdoor nitrogen dioxide (NO2) levels.
All the participants underwent lung function assessments (spirometry), skin prick tests, and measurements of total immunoglobulin (Ig)E levels in 1991 and again at follow-up in 2000. They also completed questionnaires on the occurrence of wheeze, asthma, eczema and hayfever at both time points.
After accounting for risk factors, the researchers found that participants living within 150 m of a major road were no more likely to have bronchial hyperresponsiveness, COPD, a positive skin test result, or high total IgE levels in 2000 than those who lived further away from busy roads.
Participants living close to busy roads were also no more likely to have asthma, eczema or hayfever in 2000 than those who lived further away.
Similarly, there was no evidence that higher levels of NO2 outside the home were associated with an increased risk for wheeze, COPD, bronchial hyper-responsiveness, skin sensitization, high IgE levels, asthma, eczema or hayfever.
Furthermore, participants living near to a busy road did not have a significantly greater decline in FEV1 over the 9-year period than those living further away.
However, for wheeze and allergen sensitization, the team found weak evidence for a positive dose-response relationship across the first 150 m from the roadside.
Venn and team conclude: “We found no evidence to suggest that home proximity to major roads is a major determinant of the risk of asthma, COPD or allergic disease, or progression of obstructive lung disease in adults.”
However, they add that “because of relatively high levels of background pollution in our study area and possible misclassification of exposure, we cannot completely rule out an adverse effect.”
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By Mark Cowen