Association between transportation noise and blood pressure in adults living in multi-storey residential buildings

Epidemiological studies have demonstrated that transportation noise is associated with blood pressure and hypertension, but little is known about its relationship in the adults living in multi-storey residential buildings, where neighbour noise is frequently heard. This study aimed to investigate the effects of transportation noise exposure on blood pressure in 400 adult residents of multi-storey residential buildings and modifying effects of indoor noise annoyance and self-rated noise sensitivity on the associations between transportation noise and blood pressure. Noise levels were measured on the top of buildings for 24 h, and levels of each house unit were then predicted for different sources and periods using noise maps. Adjusted linear regression analyses were performed to estimate the associations of noise exposure levels (L_DEN, L_Day, and L_Night) with systolic blood pressure (SBP) and diastolic blood pressure (DBP). The questionnaire also included questions related to annoyance caused by indoor noise, noise sensitivity, and sociodemographic variables. Adjusted regression models yielded significant effect estimates for a 5-dBA increase in overall transportation noise for 24 h (SBP β = 0.20; 95% confidence interval (CI): 0.25-1.81; DBP β = 0.16; 95% CI: 0.12-0.93). The overall (road traffic and railway noise) and road traffic noises showed stronger associations with the SBP than with the DBP, while the railway noise had similar associations with the SBP and the DBP. Stronger associations were estimated for the participants who reported higher indoor noise annoyance ratings. Furthermore, the regression coefficients between the noise exposure and blood pressure slightly increased (β = 0.26 and 0.22 for overall and road traffic noise, respectively for SBP) in a subgroup that excluded participants exposed to high railway noise. The results lend some support to the hypothesis that long-term exposure to transportation noise is associated with a higher blood pressure in adults living in multi-storey residential buildings.