Traffic noise and risk for incident atrial fibrillation

Introduction: Traffic noise exposure is associated with hypertension, ischemic heart disease and stroke. We aimed to investigate the novel hypothesis that traffic noise increases the risk for atrial fibrillation. Methods: In a population-based cohort of 57053 people aged 50-64 years at enrolment in 1993-1997, we identified 2692 cases of first-ever hospital admission for atrial fibrillation from enrolment to follow-up (2011). Historical residential addresses were identified for all cohort members (1988-2011). For all addresses, exposure to road traffic and railway noise was estimated using the Nordic prediction method and air pollution estimated using dispersion model. Cox proportional hazard model was used for analyses. Results: A 10 dB higher 5-years' time-weighted mean exposure to road traffic noise was associated with a 6 % higher risk for atrial fibrillation (incidence rate ratio: 1.06; 95% CI: 1.00-1.12) in models adjusted for lifestyle and socioeconomic position. The association followed a monotonic exposure-response relationship. In analyses with further adjustment for air pollution, estimates were attenuated and statistically insignificant. Exposure to railway noise was not associated with atrial fibrillation. Conclusions: Road traffic noise seemed associated with higher risk for atrial fibrillation. Adjustment for air pollution attenuated the results, and more studies including both traffic exposures are needed.