The short-term association of road traffic noise with cardiovascular, respiratory, and diabetes-related mortality.

BACKGROUND Road traffic noise has well-documented effects on cardiovascular, respiratory, and metabolic health. Numerous studies have reported long-term associations of urban noise with some diseases and outcomes, including death. However, to date there are no studies on the short-term association between this pollutant and a set of various specific causes of death. OBJECTIVES To investigate the short-term association of road traffic noise with daily cause-specific mortality. METHODS We used a time-stratified case-crossover design with Poisson regression. Predictor variables were daytime, nighttime, and 24-h equivalent noise levels, and maximum daytime and nighttime noise levels. Outcome variables were daily death counts for various specific causes, stratifying by age. We adjusted for primary air pollutants (PM2.5 and NO2) and weather conditions (mean temperature and relative humidity). RESULTS In the ≥65 age group, increased mortality rates per 1 dBA increase in maximum nocturnal noise levels at lag 0 or 1 day were 2.9% (95% CI 1.0, 4.8%), 3.5% (95% CI 1.1, 6.1%), 2.4% (95% CI 0.1, 4.8%), 3.0% (95% CI 0.2, 5.8%), and 4.0% (95% CI 1.0, 7.0%), for ischemic heart disease, myocardial infarction, cerebrovascular disease, pneumonia, and COPD, respectively. For diabetes, 1 dBA increase in equivalent nocturnal noise levels at lag 1 was associated with an increased mortality rate of 11% (95% CI 4.0, 19%). In the <65 age group, increased mortality rates per 1 dBA increase in equivalent nocturnal noise levels at lag 0 were 11% (95% CI 4.2, 18%) and 11% (95% CI 4.2, 19%) for ischemic heart disease and myocardial infarction, respectively. CONCLUSION Road traffic noise increases the short-term risk of death from specific diseases of the cardiovascular, respiratory, and metabolic systems.