Long-Term Exposure to Wind Turbine Noise and Risk for Myocardial Infarction and Stroke: A Nationwide Cohort Study: A Nationwide Cohort Study
Abstract
Background: Noise from wind turbines (WTs) is reported as more annoying than traffic noise at similar levels, raising concerns as to whether WT noise (WTN) increases risk for cardiovascular disease, as observed for traffic noise. Objectives: We aimed to investigate whether long-term exposure to WTN increases risk of myocardial infarction (MI) and stroke. Methods: We identified all Danish dwellings within a radius 20 times the height of the closest WT and 25% of the dwellings within 20–40 times20–40 timesthe height of the closest WT. Using data on WT type and simulated hourly wind at each WT, we estimated hourly outdoor and low frequency (LF) indoor WTN for each dwelling and derived 1-y and 5-y running nighttime averages. We used hospital and mortality registries to identify all incident cases of MI (n=19,145n=19,145) and stroke (n=18,064n=18,064) among all adults age 25–85 y (n=717,453n=717,453), who lived in one of these dwellings for ≥one year≥one year over the period 1982–2013. We used Poisson regression to estimate incidence rate ratios (IRRs) adjusted for individual- and area-level covariates. Results: IRRs for MI in association with 5-y nighttime outdoor WTN >42>42 (vs. <24<24) dB(A) and indoor LF WTN >15>15 (vs. <5<5) dB(A) were 1.21 [95% confidence interval (CI): 0.91, 1.62; 47 exposed cases] and 1.29 (95% CI: 0.73, 2.28; 12 exposed cases), respectively. IRRs for intermediate categories of outdoor WTN [24–30, 30–36, and 36–42 dB(A)36–42 dB(A) vs. <24 dB(A)<24 dB(A)] were slightly above the null and of similar size: 1.08 (95% CI: 1.04, 1.12), 1.07 (95% CI: 1.00, 1.12), and 1.06 (95% CI: 0.93, 1.22), respectively. For stroke, IRRs for the second and third outdoor exposure groups were similar to those for MI, but near or below the null for higher exposures. Conclusions: We did not find convincing evidence of associations between WTN and MI or stroke.