Long-term noise exposure and cause-specific mortality in chronic respiratory diseases, considering the modifying effect of air pollution

Background: Chronic respiratory diseases (CRDs) are among the top three causes of human mortality. The relationship between modifiable environmental risk factor of noise and risk of mortality in CRDs is unclear. We investigated the longitudinal association between environmental noise exposure and cause-specific mortality in individuals with CRDs, considering the modifying effect of air pollution. Methods: Residential noise exposure was modelled using Common Noise Assessment Methods in Europe. Information on death causes were acquired from death registry data. Cox proportional-hazards models were used to estimate effect sizes. Results: Among 41,222 participants selected from UK Biobank with CRDs in baseline, a total of 3618 death cases occurred during an average follow-up of 12 years with mortality density of 7.16 per 1000 person years. Exposure with highest noise level ( > percentile 90) were associated with 22 % (Hazard ratio [HR] = 1.22, 95 % confidence interval [CI]: 1.05, 1.42), 71 % (HR = 1.71, 95 % CI: 1.14, 2.56), and 84 % (HR = 1.84, 95 % CI: 1.10, 3.07) increased risks for all-cause, respiratory disease (RD)-cause, and COPD-cause mortalities, separately. Both multiplicative and additive interactions was found between air pollution and noise with the risk of RD-cause mortality. Participants with high air pollution and noise exposure were associated with a 101 % (HR = 2.01, 95 % CI: 1.10, 3.66) increased risk of RD-cause mortality. Conclusion: It is imperative to mitigate noise exposure as a preventive measure against incident mortality in individuals with CRDs.