Road traffic noise, mortality and incidence of cardio-cerebrovascular diseases in Rome

Abstract

Background/Aim: Transportation noise is among the most important environmental exposures contributing to the burden of disease in Europe. The aim of the study is to assess whether long-term exposure to road traffic noise is associated with mortality and incidence of coronary and cerebrovascular events in the Rome Longitudinal Study.Methods: All city residents at October 21 2001, aged 30 years and over, followed up until 31 December 2015. Lden (db(A)) and NO2 (µg/m3) concentrations were estimated at each residential address (Sound Plan 8.1, Lagrangian microscale model). The association between a 10 (db(A)) increase of Lden and non-accidental mortality, incidence of acute coronary events and stroke was assessed using Cox models adjusted for individual variables, including SEP, and NO2 concentrations (HR, CI95%). We also studied the effect of Lden (low ≤48.1 dB(A), medium 48.1-54.4 dB(A), high ≥54.4 db(A)) in three categories of NO2 concentrations (≤34.4 μg/m3, 34.4-39.9 μg/m3, ≥39.9 μg/m3) Results: 1,263,712 residents were enrolled (55% women, mean age (DS) 55 (15.4), 19% low SEP). The average population exposure levels [mean (SD)] were 53.8 (8.1) dB(A) for Lden, and 41.3 (10.1) µg/m3 for NO2 (ρ=0.47). For all the outcomes, after adjustment for NO2 we failed to find a clear association with traffic noise. However, at medium and high NO2 exposure levels we found an effect at all the noise levels considered: at Lden >54.4 db(A) we found an HR=1.05 (IC95% 1.03-1.07) for non-accidental mortality, HR=1.07 (IC95% 1.00-1.14) for fatal acute coronary events and HR=1.05 (IC95% 1.00-1.11) for stroke incidence. Conclusion: We found an independent effect of noise exposure especially at medium and high NO2 levels. Policies to reduce the exposure of residents and prevent harmful effects on their health are urgent.