Long-Term Road Traffic Noise, Air Pollution, and Cardiovascular Disease: AIRCARD: A Prospective Cohort Study

Air pollution and road traffic noise are major environmental stressors associated with cardiovascular disease (CVD). Although their independent effects are well-documented, few studies have concurrently evaluated their relative contributions-particularly in low ambient air pollution settings.

The purpose of this study was to investigate the association between long-term exposure to air pollution and road traffic noise and CVD.

We conducted a prospective cohort study using data from the DANCAVAS (Danish Cardiovascular Screening Trial) (2014-2018) and VIVA (Viborg vascular) (2008-2010) screening trials, including 26,723 men aged 65 to 74 years with pollution exposure data from 1979 to 2019. Residential exposure to air pollutants (particulate matter with a diameter <2.5 μm, nitrogen dioxide, warm-season ozone, sulfur dioxide, and carbon monoxide) and road traffic noise (L_den) were estimated based on residential addresses using the Danish Eulerian Hemispheric Model/Urban Background Model/Air Geographic Information System model and Nord2000. We used Cox proportional hazards models, adjusting for baseline inclusion year, individual-level lifestyle factors, family history of CVD, and socioeconomic status. Major adverse cardiovascular events was the primary outcome.

A 14.9 decibel increase in road traffic noise (IQR increment) was associated with a 7.5% higher risk of major adverse cardiovascular events (HR: 1.075; 95% CI: 1.026-1.128) and an 8.1% increased risk of all-cause mortality (HR: 1.081; 95% CI: 1.027-1.137). No significant associations were found between air pollutants and the primary or secondary outcomes in the pooled cohort after adjustment for confounders.

Long-term exposure to road traffic noise was significantly associated with increased CVD and all-cause mortality. Our findings suggest that studies that do not consider noise exposure may overestimate the cardiovascular burden attributed to air pollution. (Impact of Lifetime Exposure to Air and Noise Pollution on Cardiovascular Disease and Mortality-the AIRCARD Study [AIRCARD]; NCT04353232).