Traffic noise linked to higher stroke risk in older Danish men, study finds
Study of 26,723 men aged 65–74 over four decades found increased traffic noise — not long-term air pollution — was associated with a higher risk of stroke; researchers recommend reducing bedroom exposure to road noise.
Living on a noisy road, near a railway line or under a flight path was associated with an increased risk of stroke in a long-term study of older Danish men, researchers reported.
The analysis of 26,723 men aged 65 to 74 followed exposures around participants' homes over four decades and found that a 14.9-decibel increase in traffic noise — roughly the difference between a quiet side street and a main road — was linked to a 12.4% higher risk of stroke. The study measured both traffic noise and common air pollutants and found no significant association between long-term exposure to fine particulate matter, nitrogen dioxide or sulphur dioxide and stroke risk.
Investigators said traffic noise may increase stroke risk by raising stress levels and disrupting sleep. Lead author Dr. Stephan Mayntz of Odense University Hospital said in a statement that "traffic noise is a significant environmental risk factor for stroke, independently associated with a higher risk even at low levels of air pollution." Researchers advised practical steps such as sealing windows or moving bedrooms to the quieter side of a home to reduce night-time exposure to passing traffic.
The study assessed environmental exposures at participants' residences across decades, allowing researchers to compare long-term noise levels and pollutant concentrations with health outcomes. While the researchers observed the association between higher traffic noise and stroke incidence, they described the link with air pollutants as not statistically significant in this cohort.
Homes located close to major roads, rail lines or flight paths typically experience higher noise levels than quieter residential streets, the authors noted, and the measured noise increment in the study equated to a noticeable difference in everyday sound. The investigators framed traffic noise as an independent environmental risk factor warranting attention from public health officials, urban planners and policymakers.
Experts not involved in the study said addressing environmental noise could be an underappreciated component of stroke prevention, particularly in densely populated or transit-heavy areas. The study's authors called for consideration of noise mitigation measures and for homeowners and residents to take steps to reduce personal exposure, especially at night when sleep disruption may magnify health effects.
The research adds to a growing body of work examining nonchemical environmental determinants of cardiovascular disease. By reporting an association between traffic noise and stroke in a large, long-term population sample while finding no corresponding link with several common air pollutants, the study highlights the need for further research into mechanisms and for evaluation of noise-reduction interventions in real-world settings.
The findings were reported publicly on Sept. 1, 2025. The study's authors cautioned that observational results show association rather than direct causation and recommended that individuals and authorities consider available measures to limit exposure to traffic noise, particularly for older adults who may be at elevated baseline risk of stroke.