A study shows no association between night-time road traffic noise and stroke risk factors

A new study published in the journal Environment International and led by ISGlobal researcher Cathryn Tonne, has not found a significant association of long-term exposure to night-time road traffic noise with two major risk factors for stroke: hypertension and carotid intima-media thickness or cIMT (a prognostic factor of atherothrombotic events).

The results do show an association between traffic noise and cIMT among patients that did not take anti-hypertensive medication, but there was no significant effect on blood pressure or hypertension. This is the first study that analyses the relationship between this environmental exposure and the cIMT marker.

The study population consisted of more than 2,500 participants from two UK cohorts living within Greater London. The average level of exposure was 52dBA, higher than the maximum level recommended by WHO (40 dB).

According to Cathryn Tonne, previous studies had already shown a direct association between traffic noise and stroke, but “this study indicates that the cIMT or hypertension pathways are not involved”.

To confirm these findings and identify other risk factors, the authors recommend further studies with large study samples and in locations with more variation in noise exposure levels.

Reference

Halonen JI, Dehbi HM, Hansell AL, Gulliver J, Fecht D, Blangiardo M, Kelly FJ, Chaturvedi N, Kivimaki M, Tonne C. Associations of night-time road traffic noise with carotid intima-media thickness and blood pressure: The Whitehall II and SABRE study cohorts. Environ Int 2016 (in press)