Figure 1. Relationship between exposure to 3‐year means of (A) PM_2.5, (B) NO₂, and (C) road traffic noise and incident heart failure in the Danish nurse cohort (N=22 189).

Associations between 3‐year exposures to (A) PM_2.5, (B) NO₂, and (C) road traffic noise and incident heart failure in the Danish nurse cohort were expressed in a solid spline line with 95% CIs (dashed spline lines). Histograms of distribution of 3‐year exposures are drawn in light gray. Models adjusting for age (underlying time), a strata term of year of cohort entry (1993/1999), and individual‐level and area‐level covariates. L _den indicates overall weighted 24‐hour noise level; and PM₂.₅, particulate matter with a diameter <2.5 μm.